TERRA PACIS ENVIRONMENTAL METALLOYS M14 FURNACE … · KNIGHTS ENVIRONMENTAL TERRA PACIS...

KNIGHTS ENVIRONMENTAL

TERRA PACIS ENVIRONMENTAL

METALLOYS M14 FURNACE PROJECT

TECHNICAL REVIEW

DRAFT REPORT

CLIENT: Paula Tolksdorff - Terra Pacis

Author : T J P Knights

[email protected]

REPORT NO: TP M14 1.15d/ 11 DATE : January 2011

Tim Knights 07/01/2011 07:38 Page ii of 131 m14 tech rev15d.docx

B H P BILLITON M14 FURNACE PROJECT

SAMANCOR MEYERTON

TECHNICAL REVIEW

REPORT NO. TP M14 1.15d/11

DATE: January 2011

BUSINESS: METALLOYS M14 FURNACE PROJECT

TITLE: M14 FURNACE TECHNICAL REVIEW

Draft Report

CLIENT: Paula Tolksdorff – Terra Pacis

AUTHOR: T J P KNIGHTS

DISTRIBUTION:

NAME Designation Organisation No

Tim Knights 07/01/2011 07:38 Page iii of 131 m14 tech rev15d.docx

DOCUMENT APPROVAL

Client

Name Signature Date

Author

Name Signature Date

Tim Knights

Contractor

Knights Environmental

2010-1-23

DOCUMENT INFORMATION

ELECTRONIC SOURCE DATA

EFFECTIVE DATE [Date on which this document was approved]

FILE SIZE 5.73 Mb

FILENAME M14 Tech Rev 15d.docx

APPLICATION Word 2007

CHANGE HISTORY

Date Revision Description of change

2008-06-09 0 Initial Interim report, best available info for Specialists

2008-07-05 1 AH Comments (1) and GET answers

2008-08-24 2 GET second answers, S JvR answers

2008-09-05 3 Photos, FRCSs etc, new info, Disc, Concl, Summary

2008-11-04 4 AH Comments 2, GET Comments 3, Primary and secondary Off gas plants initial information.

2008-11-06

To

2009-12-13

5 -12 Feedback from M14 project Technical review meetings.

Changes from all meetings captured and recorded in revisions 5-12.

2009-12-14 13 Cover and final proof read.

2010-12-13 14 Feedback from review workshops, matched with EIA.

2011-01-20 15 Feedback from K’enyuka meetings and AH comments

Tim Knights 07/01/2011 07:38 of 131 m14 tech rev15d.docx


SAMANCOR MEYERTON

TECHNICAL REVIEW

EXECUTIVE SUMMARY

BHP Billiton have examined the market for manganese alloys and found that there is scope to expand their Metalloys operation at Samancor Meyerton. They wish to build new furnaces and refurbish others. M14 was partially constructed several years ago and the furnace shell and the raw materials handling plant building are in place. It is proposed to be constructed largely as a replica of M12 in capacity and design improvements are being made, notably in the electrode systems and in the primary and Secondary Gas cleaning Plants.

M14 will impact on many of the operations at the Metalloys site. In many of these cases where fugitive emissions are generated they will increase proportionately by the increase in production due to M14.

Also increased will be the amount of bag house dust and sludge produced.

The bag house dust will be fed to the Pelletising Plant and recycled.

The sludge will also be fed to the Pelletising Plant but the exact mechanism for this is still being determined.

M14 will also produce FeMn slag, which will go to the Pre Metrec slag stockpile. Metalloys are advancing other options to dispose of this slag.

For the primary off gas handling, new technology is being sought although it is likely to be similar to the existing plant.

Furnace fugitive emissions of dust and fume are generated from the handling of molten alloy and solid alloy and slag.

Plant is being installed, which efficiently captures fugitive emissions from the various tapping, casting operations and materials handling. A study has been carried out to determine the fugitive gas emissions points from M12 so that proper capturing facilities will be installed on M14. Consideration will be made later for installing such equipment on M12.

The captured fugitive emissions will be fed to a bag-house to be cleaned of particulate matter before release to atmosphere. The existing M17 bag house will be upgraded to be used for this. It is an existing fan system which has a high noise level (>85dB(A) at 1m). Efforts will be made to reduce this but it may still be too high and it will be demarcated as a noise area.

Most of the rest of the West Plant Operations have acceptable normal operating noise levels. The plant does have sirens for emergencies, and for operations like crane movements. This needs to be evaluated by an independent noise specialist

There are no new substances involved in the process which Metalloys is not familiar with.


When the emission data is available for all of the fugitive gas emissions and point source emissions, it will be given to dispersion study specialists, to determine the ground level concentration of the particulate matter.

Significant steps are being taken in order to have a satisfactory HSEC Management system for the factory. This is being accomplished by the introduction of the BHP Billiton HSEC standards in the form of the Group Level Documents.


CONTENTS Page No

EXECUTIVE SUMMARY ............................................................................................................. 4

Abbreviations and Definitions ..................................................................................................... 11

1 INTRODUCTION ................................................................................................................ 13

1.1 Project Description ....................................................................................................... 13

1.1.1 Origin of the proposal .................................................................................................. 13

1.1.2 The Project Proposal .................................................................................................... 14

1.1.3 Product Application ..................................................................................................... 14

1.1.4 Major equipment to be built......................................................................................... 14

1.1.5 Other Major Aspects of the Project ............................................................................. 15

1.1.6 Other Improvements .................................................................................................... 15

1.1.7 Raw Materials, Products, Solid Wastes ....................................................................... 16

1.2 Benefits of the Project .................................................................................................. 17

1.3 The Marketing and Operational Philosophy of M12 and M14. ................................. 17

1.4 The Process .................................................................................................................. 18

1.5 Ferro Alloy Production General Description ............................................................. 18

2 OVERALL SITE OPERATION AT METALLOYS ........................................................... 21

2.1 Raw Materials .............................................................................................................. 21

2.2 Product Handling ......................................................................................................... 24

2.3 Product Handling Dust Emissions .............................................................................. 24

2.4 Slag Handling .............................................................................................................. 26

2.4.1 Slag Handling Dust Emissions .................................................................................... 26

2.5 Other Site MMD Operations........................................................................................ 26

2.5.1 Pelletising Plant ........................................................................................................... 26

2.5.2 Briquetting Plant .......................................................................................................... 26

2.5.3 Sewage Plant. ............................................................................................................... 26

2.5.4 Metal Recovery Plant.(METREC) ............................................................................... 26

2.6 Elgen Plant ................................................................................................................... 27

2.7 Transport ...................................................................................................................... 27

3 MANGANESE ALLOY FURNACE M14 – PROCESS DESCRIPTION ......................... 30

3.1 Feed System .................................................................................................................. 30

3.2 Weighing and conveying of Raw Materials ................................................................ 31

3.3 Furnace Feed and Furnace Eruptions ....................................................................... 31

3.4 The Electric Arc Furnace System ............................................................................... 31

3.5 Tapping the Furnace ................................................................................................... 35


3.6 Alloy Casting ................................................................................................................ 36

3.7 Slag Casting.................................................................................................................. 37

3.7.1 Emergency Slag Casting .............................................................................................. 38

3.8 Furnace Off Gas Treatment ........................................................................................ 39

3.8.1 Primary Off-Gas System .............................................................................................. 39

3.8.2 Sludge ........................................................................................................................... 41

3.8.3 Dual Redundancy ......................................................................................................... 41

3.8.4 Primary Off-Gas Cleaning Plants switch over ............................................................ 41

3.8.5 Availability of the Primary Off-gas Cleaning Plant ................................................... 42

3.8.6 Further Improvements in the Primary Off-Gas Plant - Sumps ................................. 43

3.9 Secondary Off Gas System M14 Furnace Fugitive Gas and Fume Extraction ........ 43

3.9.1 Smoke Hood – Carbon Monoxide ............................................................................... 47

3.9.2 The Bag House ............................................................................................................. 47

3.9.3 Fan availability ............................................................................................................ 47

3.9.4 Secondary Pollution Plant Stack. ................................................................................ 48

3.9.5 Further Improvements in the Secondary Off-Gas Plant. ........................................... 48

3.9.6 Fugitive Emissions – M14 Raw Materials Handling. ................................................ 48

3.9.7 Secondary Bag House Dust ......................................................................................... 49

3.10 The Furnace Pressure Relief ....................................................................................... 49

3.11 Cooling Water Systems ................................................................................................ 50

3.12 The Control Philosophy of the M14 Furnace. ............................................................ 50

3.12.1 Resistance Control of the Electrodes. ......................................................................... 51

3.12.2 Slipping the Electrodes. ............................................................................................... 51

3.12.3 Raw Materials .............................................................................................................. 51

3.12.4 Power factor ................................................................................................................ 51

3.13 Manpower ..................................................................................................................... 51

3.13.1 Construction ................................................................................................................. 51

3.13.2 Normal Operation ........................................................................................................ 52

3.14 Plant parameters .......................................................................................................... 52

3.15 Project Responsible Parties, Design Guidelines and Construction Codes ................ 54

4 BEST AVAILABLE TECHNOLOGY. (BAT) .................................................................... 55

4.1 BAT from the Production of Iron and Steel ............................................................... 55

4.2 BAT from The Non-Ferrous Metals Industries .......................................................... 57

4.2.1 Off Gas Collection Techniques.................................................................................... 57

4.2.2 Techniques Applied in the M14 Design ...................................................................... 57

4.2.3 Use of energy ................................................................................................................ 57

4.2.4 Other Techniques to consider ...................................................................................... 58

4.2.5 Fugitive Emissions ....................................................................................................... 58


4.2.6 Face Velocity ................................................................................................................ 59

5 SAFETY HEALTH AND ENVIRONMENTAL ISSUES .................................................. 59

5.1 Safety ............................................................................................................................ 59

5.1.1 Heat............................................................................................................................... 59

5.1.2 Chemical and Material Hazards.................................................................................. 60

5.1.3 Risk areas of Operation ............................................................................................... 61

5.2 Health ........................................................................................................................... 61

5.2.1 Silica ............................................................................................................................. 61

5.2.2 Dioxins .......................................................................................................................... 61

5.2.3 Polycyclic Aromatic Hydrocarbons. (PAHs) ............................................................... 62

5.2.4 Carbon Monoxide ........................................................................................................ 62

5.2.5 Dust ............................................................................................................................... 62

5.2.6 Noise ............................................................................................................................. 62

5.2.7 Aesthetics ...................................................................................................................... 63

5.3 Working Environment ................................................................................................. 63

5.3.1 Dust ............................................................................................................................... 63

5.3.2 Noise ............................................................................................................................. 64

5.3.3 Heat stresses ................................................................................................................. 64

5.3.4 Other Physical stresses in the working environment .................................................. 65

5.3.5 Personal Protective Equipment (PPE) ........................................................................ 65

5.3.6 Medical Facilities ......................................................................................................... 65

5.3.7 Risk assessments .......................................................................................................... 66

5.4 Environment ................................................................................................................. 66

5.4.1 Solid Wastes.................................................................................................................. 66

5.4.2 Liquid Effluents ........................................................................................................... 66

5.4.3 Gaseous emissions........................................................................................................ 68

5.4.4 M14 Emissions – Dispersion Study ............................................................................. 71

5.5 Occupational Health, Safety and Environmental Management. ............................... 73

5.5.1 Quality Control Management system: Procedure No SHEQC 015 ........................... 73

5.5.2 BHP Billiton Occupational Health Safety Environmental Management ................. 74

5.6 Emergency Facilities.................................................................................................... 76

5.7 Risk to the public .......................................................................................................... 77

6 ASSESSMENT OF ALTERNATIVES ............................................................................... 77

6.1 Alternatives to the SAF Process .................................................................................. 77

6.2 Alternative Sites............................................................................................................ 77

6.3 Other Alternatives ........................................................................................................ 77

7 DISCUSSION AND CONCLUSIONS ................................................................................ 78

7.1 Expansion ..................................................................................................................... 78


7.2 The Marketing Philosophy of M12 and M14. ............................................................. 78

7.3 Design of M14 .............................................................................................................. 79

7.4 Primary Off-Gas System .............................................................................................. 79

7.5 Fugitive emissions - Site .............................................................................................. 79

7.6 Fugitive emissions – M14 ............................................................................................ 79

7.7 Furnace Pressure Relief .............................................................................................. 79

7.8 Furnace Hood .............................................................................................................. 79

7.9 Secondary Off-Gas System .......................................................................................... 80

7.10 Furnace Cooling .......................................................................................................... 80

7.11 Power. ........................................................................................................................... 80

7.12 Best Available Technology........................................................................................... 80

7.13 HSEC Issues ................................................................................................................. 80

7.13.1 Dust ............................................................................................................................... 80

7.13.2 Manganism ................................................................................................................... 81

7.13.3 Noise ............................................................................................................................. 81

7.14 Alternatives ................................................................................................................... 81

7.15 Missing Information .................................................................................................... 81

8 RECOMMENDATIONS ..................................................................................................... 81

9 OUTSTANDING INFORMATION .................................................................................... 81

10 REFERENCES .................................................................................................................... 81

11 APPENDICES ..................................................................................................................... 83


List of Figures and Tables

Figure 1: Typical Submerged Arc Furnace Design 20 Figure 2: Materials Block Diagram – Site and M14. 23 Figure 3: Overall site flow Scheme 25 Figure 4a: Waste Block Diagram M14 Furnace Project – FeMn Operation. 28 Figure 4b: Waste Block Diagram M14 Furnace Project – SiMn Operation. 29 Figure 5: Raw materials handling plant – M12 - left; The partially constructed M14-

Right. 30 Figure 6: The partially constructed M14 Furnace Shell. 32 Figure 7: Fail Safe Slipping Device. 33 Figure 8: Typical Lower Electrode Assembly. 34 Figure 9: Alloy Tapping into a Ladle at Existing M12 at West Plant. 36 Figure 10: M12 Alloy Being Decanted Directly Into the Oxygen Blown Converter (OBC) 36 Figure 11: Casting Beds. 37 Figure 12: Slag Being Tapped Directly into a Molten Slag Carrier Ladle. 38 Figure 13: A Primary Off-Gas System proposed for M14 . 39 Figure 14: Existing M12 Primary Off-Gas System. 40 Table 1: Furnace Off-Gas Specification 40 Figure 15: Existing M12 Secondary Off-Gas Bag-houses. 44 Figure 16: M14 Smoke Hood Fume Extraction 44 Figure 17: Proposed M14Secondary Off-Gas System - Furnace Dust Extraction. 45 Table 2: Air Flows from Furnace areas of M12 and M14. 46 Figure 18: Existing M17 Bag-house for M14 use. 48 Figure 19 Plot Plan of the Furnace Area 53 Figure 20: Tap-Hole Fume Collection as Applied to a Blast Furnace. 59 Table 3: Temperatures in the Furnace Plant 60 Table 4: Noise levels for the various parts of the plant 63 Figure 21: Water Balance 67 Figure 22: Dioxin Molecular Structure 127


ABBREVIATIONS AND DEFINITIONS

Abbreviation Description ANSI American National Standards Institute CCCW Closed Circuit Cooling Water CMS Contractor Management System dB Decibels EAF Electric Arc Furnace EPCM Engineering Procurement Construction Maintenance ESP Electro static precipitator EU IPPC European Union Integrated Pollution Prevention and Control FEL Front end Loader FeMn Ferromanganese FRCS Fatal Risk Control Standards g/l Grams per litre HSEC Health, Safety, Environment and Community Metrec Metal recovery plant mg/m3 Milligrams per cubic metre MMD Materials Management Department MSDS Material Safety Data Sheet MVA Mega Volt Ampere MW Mega Watts Nm3/h Normal cubic metres per hour (ie at 25oC and 1 atmosphere) NWPSD New West Plant Slimes Dam NNPSD New North Plant Slimes Dam OEL Occupational Exposure Limit OHS Act Occupational Health and Safety Act PAH Polycyclic aromatic hydrocarbons. Also known as Coal Tar

Pitch Volatiles PPE Personal Protective Equipment ppm Parts per million RM(H) Raw Materials (Handling) PSE Point Source Emission SABS South African Bureau Of Standards SAF Submerged Arc Furnace SHE Safety Health And Environment SHEQC Safety Health Environment Quality and Community SiMn Silicomanganese t/a; t/d; t/h Tons per annum; Tons per day; Tons per hour t/month Tons per Month US EPA United States Environmental Protection Agency


Definitions:

Ferroalloy

An alloy of iron with some element other than carbon. Ferroalloy is used to physically introduce or "carry" that element into molten metal, usually during steel manufacture. In practice, the term ferroalloy is used to include any alloys that introduce reactive elements or alloy systems.

OHSAS 18001:

A guideline for the implementation of a risk based occupational health and safety management system.

Fume:

The particulate smoke like emanation from the surface of molten alloy and other materials like molten slag.

Dust:

Particulate matter, typically less than 10µ, generated by attrition or crushing of larger size material.

“Heel” of metal:

When the furnace is drained of alloy a small quantity of alloy is left below the tap-hole inside the furnace. This alloy left inside the furnace is called a “Heel” of metal



SAMANCOR MEYERTON

TECHNICAL REVIEW

1 INTRODUCTION

Samancor Manganese (Pty) Ltd trading as Metalloys, resourcefully operated by BHP Billiton at the Samancor Works at Meyerton, beneficiate manganese ores and manufacture Ferromanganese (FeMn) and Silicomanganese (SiMn) alloys. This is carried out by means of the submerged arc furnace (SAF) process. In the M12 and M14 process off-gas rich in carbon monoxide and hydrogen is generated which is cleaned using scrubbers. The clean gas together with the gas from furnaces M10 and M12 of North Plant is then fed to the electricity generation plant (Elgen).

The factory was started in 1951 producing manganese alloys from the manganese ore reserves that occur near Hotazel in the Northern Cape. These reserves are the largest in the world. The factory has grown over the last 50 years and now utilizes several electric arc furnaces, three of which are amongst the largest in the world. M14 will be as big as these furnaces. FeMn and SiMn are produced in these furnaces using the submerged arc furnace process.

BHP Billiton owns 60% of the Samancor business, with Anglo American Corporation owning the 40% balance. Samancor business includes the manganese mines at Hotazel and certain Australian assets.

FeMn is manufactured at the Metalloys North Plant (Furnaces M10 and M11) and West Plant which currently has the submerged arc furnace M12. Metalloys have determined that there is a market for more manganese alloys (Mn alloys) and, accordingly, are investigating a project to build a further furnace, M14. The proposed M14 Furnace will be an 81MVA furnace producing 146 000 tons per annum (t/a) of “Hot” Mn alloy final product. The new furnace will be modeled on the current design and operation of the M12 Furnace. The target date for the commissioning of M14 is June 2012.

FeMn alloy and SiMn alloy are used in the metallurgical industry for making special grades of alloyed steel.

1.1 Project Description

1.1.1 Origin of the proposal

With the increased general growth worldwide, the demand for steel and the corresponding demand for manganese units will increase. Accordingly Metalloys are expanding their capacity.

M14 will also provide more primary off-gas which in turn will generate more power from Elgen. Elgen has the capacity to take the gas and provide an anticipated additional 10 MW.

That will enable more power to be generated for the Metalloys site in a short to medium term. Eskom in the meantime is increasing its


capacity and the future power policy of Metalloys is being determined.

By the time Eskom has reached designed capacity Metalloys will have completed its medium term projects and be able to meet the market demand.

M14 will provide a better market stance for BHP Billiton; it is being built at the time of power shortage, but when the power returns in greater quantity in 2013, M14 and other projects will be built or have been carried out and will be able to benefit from the increased power availability.

The project will cost in the region of R700 million.

1.1.2 The Project Proposal

To build the M14 Furnace, and associated plant and equipment. M14 will be a 48MW furnace producing 146 000t/a Mn alloy at 2.45 to 2.55MWh/t. For more details see 1.1.4 below.

The M14 Furnace will be a close replica of M12. It is already partly constructed and this project will be the completion of that original project.

The furnace will be largely the same as M12; however a newer/different Electrode column may be installed and could potentially result in minor changes to the roof design.

M14 will be a continuous operation with batch tapping of the furnace; its availability will be 98%.

1.1.3 Product Application

Mn Alloys are used in the iron and steel industry mainly, they have two functions:

Manganese removes sulphur from steel and silicon removes oxygen. In this way SiMn and FeMn Alloys, which are being manufactured by Samancor, effectively clean the steel of these impurities. As an alloying agent, manganese increases the hardness of the steel.

Integrated steel manufacturing companies own iron ore bodies and manufacture iron using a blast furnace (BF) and direct reduced iron (DRI) processes and other processes in the steel works to manufacture the steel. These companies take manganese ore and manganese alloys and use them at the most appropriate stage in the manufacture of steel.

1.1.4 Major equipment to be built

a. The construction of the partially built M14 Furnace will be completed.


M14 will be an 81MVA submerged arc furnace smelter with a carbon freeze lining.

The furnace shall operate at around 43-48MW; this corresponds to approximately 60 - 65MVA, and this shall be the constant operation band with power factor correction. The furnace will be capable of operating with an electrical maximum of 81MVA.

The main process equipment is as follows:

i. Raw materials system ii. Bottom-cooled 81MVA submerged arc furnace with

carbon lining. iii. Hot-alloy handling (ladles, overhead cranes, hot alloy

scale). iv. Final-product handling (casting bays, bulk mechanical

vehicles, final product handling process).

b. Complete the building of The M14 Furnace raw materials handling plant.

c. Refurbish the old M17 bag-house and tie it in to the M14 de-dusting equipment.

d. Build a new primary off-gas cleaning plant; using a wet scrubbing system similar to the existing M12 system but with minor improvements.

1.1.5 Other Major Aspects of the Project

a. The existing M17 bag-house, currently unutilized will be used as a secondary pollution plant for capturing fugitive emissions from tapping, pouring and casting at M14.

b. Other items such as the ladle heaters and repair areas will also be relocated. This will require the further relocation of the manganese alloy storage area.

It’s to be noted that no dedicated manganese alloys store exists on the West Plant site. Hence following the approximate three days of cooling within the casting beds, the product (manganese alloy) is loaded by front end loaders onto haulers / trucks for transport to the MMD plant for crushing, screening and stock piling for distribution.

1.1.6 Other Improvements

a. Control Room and Plant Offices Location

Studies have been carried out on the location of the control room and plant offices and it has been decided to relocate offices and control room, currently in the furnace building, to a safer location.


They are to be placed in the area between the furnaces and the Raw Material Silo which will be some distance from the furnace and thereby safer. This control room will be for M14 as well. However this is a West Plant project and is not part of the M14 project.

b. Furnace Tapping

Better ergonomics will be incorporated into the design of the equipment. Latest technology guns and drills will be used for both Mn Alloy and slag tapping operations. This will improve health and safety aspects.

c. Maintenance

The plant will be designed to be largely the same as M12. There could be some changes to the maintenance procedures to improve the efficiency and operation. More space will be made available to improve ergonomics and furnace operability.

d. Fugitive Emissions

Consultants are looking at the most appropriate design to capture fugitive emissions from tapping, and casting operations.

e. Storage of Raw Materials

M14 was partially constructed and in place is the shell of M14 Furnace and shell of the raw material silos.

These raw material silos will be completed as per the original design.

There is currently a study being carried out by Materials Management Department (MMD). It is a raw material handling (RMH) feed and stockpile management study. It will involve studies of the stockpile conveyer belt reclaimers to ensure that raw materials can be supplied to the M14 Furnace in sufficient quantities.

1.1.7 Raw Materials, Products, Solid Wastes

Raw Materials

Ores

a. Manganese Ores.

b. Manganese Sinter.

c. Iron Ore.

Reductants

d. Coal.


e. Coke.

f. Anthracite.

Flux

g. Quartz (Silica).

h. Dolomite.

i. Limestone.

Products

j. Mainly 76% and 78% FeMn Alloy and 64-65% SiMn Alloy with 16-18%Si. Other ranges could be produced

Solid Wastes

k. Primary off-gas cleaning sludge.

This will be stored in the dams and later pelletised and recycled.

l. Bag-house secondary off-gas clean dust.

This will be stored next to the Post Metrec slag stockpile in bag-filter dust stockpiles 1 and 2. It is later to be pelletised and recycled.

m. Mn alloy Slag

This will be stored on the Mn alloy Pre Metrec slag stockpile.

For all Materials Specifications see Appendices 11.2 to 11.34

1.2 Benefits of the Project

Metalloys will match the market increase for the Manganese Alloys and thereby maintain and even increase its market share.

There will be a small increase in employment for M14, although much of the operator and the engineering maintenance work will be carried out by the existing team. 400 people will be employed for the project construction.

1.3 The Marketing and Operational Philosophy of M12 and M14.

The capacity of OBC currently matches the production rates of either M12 or the proposed M14.

Currently all of the High Carbon Ferromanganese (HCFeMn) produced by M12 is intended for the OBC plant, to process it into Medium Carbon Ferromanganese (MCFeMn), and that is intended to continue. The new M14 Furnace product is intended to be cast into the casting beds, crushed and sold as HCFeMn.

In practice the timing of the OBC operation will determine whether the HCFeMn Feed will come from M12 or M14; whichever is nearest to being ready to be tapped.


The balance of the alloy from either M12 or M14, which will be surplus to the OBC requirement, will be cast into the casting beds, to be sold as HCFeMn.

1.4 The Process

The process consists of the continuous feeding of ores, reductants and fluxes into the furnaces where computer controlled electric smelting produces the Mn alloy product.

The ingredients consist of:

1. Manganese ores and sintered manganese ores 2. Iron Ore 3. Quartz-silica 4. Reductants coal, anthracite and coke 5. Recycled materials

These ingredients are brought into the raw materials handling section of West Plant by means of a conveyor belt. The ingredients are weighed accurately and placed into a mixing bin before feeding to the furnace in which there are three electrodes which generate an electric arc, and the heat of the arc causes the reaction to occur.

In the reaction, the iron and manganese oxides in the ores are reduced by carbon reductants coal and coke to iron and manganese which, together, form a Mn alloy.

The molten Mn alloy finds its way to the bottom of the furnace. Floating on the surface is slag, a mixture of all the foreign material (gangue) that comes with the ore and reductants. They mix with the silica and fuse together to form slag which under these conditions is a mobile liquid. As the level of alloy grows in the bottom of the furnace, a hole is made in the side of the furnace (tapping) and the slag is released into a large ladle which is carried away by a special carrier.

From a separate hole the alloy is released into another ladle. After weighing, the alloy ladle is moved to an area of ground where it is cast and allowed to solidify. The alloy is picked up by a front-end loader and dispatched to materials handling where it is crushed and sized and packaged for dispatch and sale.

The molten Mn alloy slag is transported by means of the molten slag carrier to the Mn alloy Pre-Metrec slag stockpile. The furnace generates much fume and dust from the processes, tapping alloy and slag, running in the launder, pouring into a ladle and casting into a mould. This fume and dust is extracted and then filtered by the Secondary Off-gas plant to a low level of dust before being released to atmosphere.

1.5 Ferro Alloy Production General Description

(This is a general description extracted from US EPA AP42 Chapter 12.4)

Ferroalloy is an alloy of iron with some element other than carbon. Ferroalloy is used to physically introduce or "carry" that element into molten metal, usually during steel manufacture. In practice, the term ferroalloy is used to include any alloys that introduce reactive elements or alloy systems.


The ferroalloy industry is associated with the iron and steel industries, its largest customers. Ferroalloys impart distinctive qualities to steel and cast iron and serve important functions during iron and steel production cycles. The principal ferroalloys are those of chromium, manganese, and silicon. Chromium provides corrosion resistance to stainless steels. Manganese is essential to counteract the harmful effects of sulphur in the production of virtually all steels and cast iron. Silicon is used primarily for deoxidation in steel and as an alloying agent in cast iron.

Description of the Ferro Alloy Process

A typical ferroalloy plant is illustrated in Figure 1. A variety of furnace types, including submerged electric arc furnaces, exothermic (metallothermic) reaction furnaces, and electrolytic cells can be used to produce ferroalloys. The Submerged Electric Arc furnace (SAF) is used at Metalloys.

The Submerged Electric Arc Process

In most cases, the submerged electric arc furnace produces the desired product directly. It may produce an intermediate product that is subsequently used in additional processing methods. The submerged arc process is a reduction smelting operation. The reactants consist of metallic ores (ferrous oxides, silicon oxides, manganese oxides, etc.) and a carbon-source reducing agent, usually in the form of coke, high- and low-volatility coal. Limestone and/or dolomite and quartz may also be added as a flux material. Raw materials are crushed, sized, and, in some cases, dried, and then conveyed to a mix house for weighing and blending. Conveyors, buckets, skip hoists, or cars transport the processed material to hoppers above the furnace. The mix is then gravity-fed through a feed chute either continuously or intermittently, as needed. At high temperatures in the reaction zone, the carbon source reacts with metal oxides to form carbon monoxide and to reduce the ores to base metal. A typical reaction producing Mn alloy is shown below:

MnO2 + 2 C → Mn +2 CO

The generic reaction is below:

MxOy +YC → XM +YCO

Smelting in an electric arc furnace is accomplished by conversion of electrical energy to heat. An alternating current applied to the electrodes causes current to flow through the charge between the electrode tips. This provides a reaction zone at temperatures up to 2000°C. The tip of each electrode changes polarity continuously as the alternating current flows between the tips. To maintain a uniform electric load, electrode depth is continuously varied automatically by mechanical or hydraulic means.


Figure 1: Typical Submerged Arc Furnace Design

A typical submerged electric arc furnace design is depicted in Figure 2. The lower part of the submerged electric arc furnace is composed of a cylindrical steel shell with a flat bottom or hearth. The interior of the shell is lined with 2 or more layers of carbon blocks. The furnace shell may be water-cooled to protect it from the heat of the process. A water-cooled cover and fume collection hood are mounted over the furnace shell. Normally, 3 carbon electrodes arranged in a triangular formation extend through the cover and into the furnace shell opening. Self-baking (Soderberg) electrodes ranging from 76 to 200 cm in diameter are typically used. Raw materials are charged to the furnace through feed chutes from above the furnace. The surface of the furnace charge, which contains both molten material and unconverted charge during operation, is typically maintained near the top of the furnace shell. The lower ends of the electrodes are maintained at about 0.9 to 1.5 meters below the charge surface. Three-phase electric current arcs from electrode to electrode, passing through the charge material generating large quantities of heat. The charge material melts and reacts to form the desired product as the electric energy is converted into heat. The carbonaceous material in the furnace charge reacts with oxygen in the metal oxides of the charge and reduces them to base metals. The reactions produce large quantities of carbon monoxide (CO) that passes upward through the furnace charge. The molten alloy and slag are removed (tapped) through 1 or more tap holes extending through the furnace shell at the hearth level. Feed materials may be charged continuously or intermittently. Power is applied continuously. Tapping can be intermittent or continuous based on production rate of the furnace. Continuous tapping furnaces are rare; M14 will be an intermittent tapping type.


Submerged electric arc furnaces are of 2 basic types, open and closed. M14 will be a closed type.

In a closed furnace the off-gases are not combusted but captured and can be used for energy recovery. They are contaminated with dust and tar and have to be cleaned usually by a scrubbing process.

The molten alloy and slag that accumulate on the furnace hearth are removed at 1 to 5-hour intervals through the tap hole. Tapping typically lasts 10 to 15 minutes. Tap holes are opened by drilling, and by oxygen lancing. The molten alloy and slag flow from the tap hole into a carbon-lined trough, then into a carbon-lined runner that directs the alloy and slag into a ladle, ingot molds, or chills. (Chills are low, flat iron or steel pans that provide rapid cooling of the molten metal.) After tapping is completed, the furnace is resealed by inserting a carbon or a refractory paste plug into the tap hole.

During tapping, and/or in the ladle, slag is skimmed from the surface of the molten metal. It is disposed of on the Pre Metrec slag stockpile, or used as a raw material in a furnace or reaction ladle to produce a chemically related ferroalloy product.

After cooling and solidifying, the large ferroalloy castings may be broken up, and then crushed, screened (sized), and stored in bins until shipment.

2 OVERALL SITE OPERATION AT METALLOYS

For overall site operation see Figure 4.

2.1 Raw Materials

Raw materials for the Metalloys works arrive by either road or rail. The rail material is tippled and sprayed with dust suppressant and then conveyed to stockpiles for each of the raw materials. The dust suppressant is effective for 26 days. Within that period the material is dispatched to the various plants.

The material that is delivered by road is tipped into piles in the raw materials handling area, and because dust suppressant cannot be applied then dust is released during this operation. These piles are generally used for emergencies should the materials be in short supply. When the materials are reclaimed from these piles more dust is generated. The materials are put into hoppers from where they are conveyed to the West, North and South Plants by conveyor belt, where they are discharged into the plant silos. See plant description. When discharged into the hoppers dust suppressant is added.

The current raw material flows to the site are shown in Figure 3 plus the flows that will go to M14 to show the impact that that furnace will have on raw material flows.

An average of 150 000 tons per month of raw materials are received by the site when all furnaces are in operation. 45% arrive by road and 55% by rail.

The furnaces are supplied as follows:

North Plant – Furnaces M10 and M11


West Plant – Furnace M12 and the proposed M14

Furnaces M16 and M17 are not utilized.

South Plant – Furnaces M1 – M5.

For details of all raw materials, products and auxiliary materials, see Appendix. 11.2 to 11.34.

For a Site Materials Flow Diagram showing how M14 material flows impact on the site see Figure 3. For Metalloys Baseline Emissions Report see Ref 10.26.

M14 will increase raw material and power consumption by approximately 25%. Fugitive emissions from materials handling can be expected to increase by that proportion. This will be quantified by the dispersion study specialists.

The emissions are based on the guaranteed figure for the filter bags of 30mg/Nm3. In practice Metalloys have found this to be <5mg/Nm3 and often <1mg/Nm3.


Figure 2: Materials Block Diagram – Site and M14.

108 t/a 136 t/a 75.5 t/a 26.4 t/a 26.2 t/a 43.5 t/a 36.7 t/a 161 t/a

SiMn 131 kt/a 146 kt/a

FeMn 411 kt/a

SiMn Slag 151 kt/a 21.9 kt/a 23.3 kt/a 10.3 kt/a 120 kt/a 86 kt/a

FeMn Slag 320 kt/a

Mn Ore

Quartz

Reductants

Other Materials

Electrode Paste

Power

275

14

73

0

0.1

43 MW

M14 Furnace

M14 Off-gas scrubbing Plant Pelletising and

Dams

M14 Secondary Off-gasPlant

Existing Furnaces at Metalloys

South Plant Primary and Secondary

Off-gas Plantsand Elgen

North Plant Secondary

Off-gas Plant

Fe-Mn Product to crushing and

Dispatch

Molten Slag to dumpSlag to Dump

Products to crushing

and Dispatch

Dust to Dump.

Gas Plants

t/a x 1000

Dust to Pelletizing .

1 095

135

320

131

12

192 MW

PM

SludgeSludge to dams and Pelletizing

West PlantSecondary

Off-gas PlantFurnace Fugitives

Other Fugitives

M14 Furnace Fugitives

M14 Other Fugitives


2.2 Product Handling

Mn Alloy products are handled by MMD in two areas:

1. Advalloy (West Plant) Product Handling 2. Central Product Handling

From West Plant the High Carbon Mn alloy is cast and allowed to set and crack into pieces.

It is conveyed by front-end loader and truck to MMD Central Product Handling where the material is crushed and screened in certain size ranges for sale. The size ranges are as follows:

• 80 - 50 mm • 50 - 25 mm • 25 - 10 mm • 10 - 5 mm • 5 – 3 mm • 3 – 0 mm

After the cast material is passed to the primary crushers in both Product Handling areas. It is kept wet by water sprays to suppress dust.

The 3-5 mm size range can be blended in with the other so-called “salting”.

0 – 3 mm is sometimes sold but normally it is briquetted at the Metalloys briquetting plant.

After crushing and screening, the materials are put into fraction bins which are the storage bunkers for all grades. A front-end loader loads rail or road trucks with the specified product size range.

Some product is bagged at the Advalloy (West Plant) Product Handling and dispatched in containers.

The product vehicles then pass over a weighbridge before being dispatched to the customers.

2.3 Product Handling Dust Emissions

The crushing and screening of the Metalloys products requires several handling stages each of which results in a fugitive or area dust emission.

M14 will increase the Product Handling dust emissions proportionally by the amount of product it manufactures. This will be quantified by the dispersion study specialists.

Products: 50% are dispatched by rail and 50% by road.


Figure 3: Overall site flow Scheme

3

Water 2

Sludge

Sludge Dams

2

Gas-Plants

Venturi ScrubbersSludge

CO - gas

Furnace

3 Water

Metal

Recovery

Recovered

Clean

Sale

Sale

Slag

Raw Slag

Incoming Raw Materials

Raw Materials

Stock piles

Casting Beds

Crushing

Final ProductDispatch

Power Plant

Oxygen Blown Converter

Mn- Alloy

Submerged

Arc- Furnace

Bunkers

Electricity

Pelletising Plant

HC FeMn

MC FeMn


2.4 Slag Handling

Slag is handled by a contract service provider. It is carried in a molten slag carrier to the Pre-Metrec slag stockpile and from there to the metal recovery plant. See 2.4.4 below. The metal-free slag is then stored at the Post Metrec stockpile.

Metalloys are considering changing to a new technology which has a cheaper operation with less risk.

2.4.1 Slag Handling Dust Emissions

The casting and crushing of slag will generate dust emissions from each of the process stages.

2.5 Other Site MMD Operations

Materials Management Department is also responsible for certain processing plants: the Pelletising Plant, the Metal Recovery (Metrec) Plant and the Briquetting Plant. The Sewage Plant is managed by the Laboratory.

There is also an Electricity Generation Plant (Elgen), which will utilize the primary off-gas generated by M14 in a boiler to generate steam which in turn drives a turbine driven generator to generate power.

2.5.1 Pelletising Plant

In this process, dust from bag houses, various sludges and water are mixed together with a binding agent and are fed to the Pelletising Plant. This generates a product rich in manganese from waste material which can then be fed into the South Plant furnaces to recover the manganese.

2.5.2 Briquetting Plant

The briquetting plant takes Mn alloy fines and Admox dust which are mixed with a starch solution as a binder and compressed by a briquetting machine in to spherical briquettes. These are then fed to the appropriate furnaces.

2.5.3 Sewage Plant.

Metalloys operates a trickle filter sewage plant for processing sewage generated on the site.

The plant capacity is 100m3 per day. It has very low volumes since Polyphos shut down. (<30m3). With full contractor presence on site the plant seldom receives above 50m3 per day.

So there is plenty of capacity for M14 personnel.

2.5.4 Metal Recovery Plant.(METREC)

The Mn alloy slag is crushed to a size range of <38mm releasing some entrained metal. The metal recovery plant (Metrec) process


recovers this alloy using the jigging process. The alloy can be sold directly or go to Briquetting.

2.6 Elgen Plant

The scrubbed off-gas from the Metalloys Mn alloy Furnaces M10, M11 and M12, which are closed furnaces, is rich in carbon monoxide and hydrogen. It is used in the Elgen unit to raise steam and generate power which feeds the Metalloys electrical grid and contributes to the power requirements of the site.

2.7 Transport

All raw materials are moved into the site and all products leave the site using rail and road trucks. All main raw materials are moved to the plants using conveyor belts. Intermediate materials are to be moved within the site using FELs and dump trucks. Molten slag is normally moved using molten slag carriers.

For Transport movements on the site see Ref 10.9.

Waste Block Diagrams and Mass Balance

In the Waste Block Diagrams and Mass Balance flow diagrams below the scheme followed is to have the raw materials coming in from the left, and products leaving from the right.

Wastes are coloured red. Gaseous wastes leave from the top, and solid wastes leave from the bottom. There are no liquid wastes.

Several different ores may be used, several different reductants may be used and several different fluxes maybe used. The recipe of raw materials however is typical and will not be significantly deviated from.


Figure 4a: Waste Block Diagram M14 Furnace Project – FeMn Operation. Fume and dust t/h 0.0051 0.0188 Other fugitive emissions 0.0041 0.03 t/h

Emissions t/a Total 43.50 161.22 from Furnace operation Total 35.14 240 t/a

See DefinitionsAm3/h

30mg/m3

10.65 t/h91 454 t/a

32.08 t/h275 429 t/a 1.20 t/h

10 302 t/a

8.47 t/h72 713 t/a

17.05 t/h146 407 t/a

1.66 t/h14 244 t/a

0.00 t/h0 t/a

0.21 t/h 0.01 t/h1 764 t/a 86 t/a

Nil

Those RMs with zero usage can 0.00 t/h 13.98 t/h 13.98 t/hbe included in the recipe 0.00 t/a t/a 120 054 t/a

42.42 t/h TOTALS IN Availability 0.98 1.00 t/h TOTALS OUT 42.93 t/h

364 150 t/a Factor Mt/a : t/h 8 584.80 t/a 368 543 t/a

Product Raw Material

Ref Recipe 70:20:10 for 76%Mn Wastes Stock Pile

220 Batches of 4,605t per day. 2.58 MWh/t metal

Combined metal Tapping Fugitive emissions

Other fugitive emissions from Furnace Operation

626 000

Gaseous, solid & l iquid

120 054.10


Figure 4b: Waste Block Diagram M14 Furnace Project – SiMn Operation. Fume and dust t/h 0.0051 0.0188 0.0041 0.03 t/h

Emissions t/a 43.50 161.22 0.00 0.00 0.00 0.00 0.00 240 t/aSee Definitions

Am3/h30mg/m3

10.77 t/h92 458 t/a

20.53 t/h176 223 t/a 2.10 t/h

18 028 t/a

6.88 t/h59 034 t/a

11.12 t/h95 453 t/a

7.46 t/h64 073 t/a

0.01 t/h86 t/a

0.29 t/h2 470 t/a

Those RMs with zero usage can

be included in the recipe 0.01 t/h 11.12 t/h 11.13 t/h85.85 t/a t/a 95 539 t/a

35.16 t/h TOTALS IN Availability 0.98 1.00 t/h Balance TOTALS OUT 35.16 t/h

301 799 t/a Factor Mt/a : t/h 8 584.80 t/a 0.00 301 804 t/a

Product Raw Material

Ref Recipe 70:20:10 for 76%Mn Wastes Stock Pile

220 Batches of 4,605t per day. 2.58 MWh/t metal

Combined Tapping Fugitive emissions

626 000

Gaseous, solid & l iquid

95 453.19


3 MANGANESE ALLOY FURNACE M14 – PROCESS DESCRIPTION

The M14 Furnace will produce more than 400 tons/day of FeMn alloy and more than 350 tons/day of FeMn alloy slag.

The furnace produces typically 76% Mn alloy. At times the market calls for 78% Mn alloy; in this case the recipe is adjusted to increase the Mn content of the feed.

M14 is also designed to produce SiMn alloy.

3.1 Feed System

The different raw materials RM1-10 as listed below will arrive at West Plant by the existing conveyor belts from raw materials management operations of MMD.

They are conveyed to sixteen bunkers per material type.

The sixteen silos are 70m3 capacity and can hold 150 - 200 tons of RM each.

The ingredients are fed via vibrators into weigh hoppers. Exact amounts of each ingredient are weighed according to a recipe. The recipe is for a 4.6ton batch; 220 to 250 batches are fed to the furnace every day to produce 409.3 tons/day of FeMn alloy and 364 tons/day of FeMn alloy slag.

Figure 5: Raw materials handling plant – M12 - left; The partially constructed M14- Right.

The raw materials are:

Ores: o Manganese ores (local/imported); o Manganese sinter; o Other metallics; o Recycled waste material.


Flux: o Quartz; o Limestone; o Dolomite.

Reductants: o Coke; o Coal; o Anthracite.

The raw materials are conveyed to dedicated silos per material type.

From the silos the raw materials are fed into weighing hoppers where the exact amounts of each raw material are weighed according to the recipe.

3.2 Weighing and conveying of Raw Materials

After the ingredients have been weighed according to the recipe, they are conveyed to a mixing bin. It is a static bin and no physical mixing occurs; but all the ingredients are arriving continuously and an even distribution of material occurs as it is charged into the furnace. The material then passes to the 16 furnace day bins where the level is controlled. From the day bins the material passes by 16 feed chutes directly to the furnace burden. As the reaction proceeds the raw materials are consumed causing more raw materials to flow down the chutes into the furnace by gravity.

Sixteen bins and chutes are used to ensure an even distribution of the material in the burden of the furnace. Without that even distribution the furnace could go out of balance causing bridging followed by collapsing and furnace eruptions. Although the eruptions could be contained it is likely that they could result in a release of gas to the atmosphere.

3.3 Furnace Feed and Furnace Eruptions

In the furnace reaction zone deep under the furnace burden, gas is generated.

This gas has to pass through the burden in order to escape. It is important that the burden is porous to allow the passage of the gas. To ensure this porosity the raw materials are pre-screened by the supplier or on site to ensure a maximum of 10% fines (-6mm) is present. This gives a porosity of raw material in the bed which ensures good spreading of gas when released and good heat transfer.

This gas has to pass through the burden in order to escape. It is important that the burden is porous to allow the passage of the gas. There have been many reported incidents in the operation on such furnaces where this porosity has been limited. The burden has formed a crust and in order for the gas to escape pressures have built up that have caused the burden to erupt, sometimes causing considerable damage and injury to personnel.

3.4 The Electric Arc Furnace System

The electric arc furnace (EAF) consists of a refractory lined furnace vessel which is 15.5m diameter and 7.7m high. The furnace burden is typically 6 to 7m deep, and submerged under this burden are the three electrode tips.


The three electrodes, 1.9m diameter, are of a Soderberg type electrode system. In the Soderberg system electrodes are continuously made on a floor above the furnace. Each electrode weighs approximately 60 tons.

Three 1.9m diameter steel tubes descend into the furnace hearth and are continuously filled with electrode paste, which is a solid mixture of tar and carbon sources such as anthracite and coke. As the steel tubes descend into the hot furnace, the electrode paste melts and slowly bakes into a hard carbon-based electrode material. As the steel tubes submerges under the furnace hearth and approaches the electric arc, the steel casing melts away, leaving the carbon electrode.

The Soderberg type electrode system design is similar to the design of M12 furnace.

Figure 6: The partially constructed M14 Furnace Shell.

The Metix Electrode System

Fail Safe Slipping Device.

The electrodes are locked in place by sprung loaded cables. Hydraulic pressure is used to release them. If the hydraulic pressure is lost due to failure or an interlock signal, the electrodes will be locked in place.


Figure 7: Fail Safe Slipping Device.

Low Pressure Ring System and Contact Shoes.

This device is manufactured from solid forged Copper Silver alloy material which has a longer life; the water bellows system enables easier maintenance than the conventional system that is used on M12.

Water cooled Power Flexibles

These will also enable easier maintenance than is currently required for the inverted “U” flexibles that are used on M12.

Copper heat shield

This is more stable and resistant to heat stress the than the stainless steel heat shield used in M12.


Figure 8: Typical Lower Electrode Assembly.

The electrodes are capable of supplying 81 MVA in total to the furnace as energy and this is controlled by the secondary windings of the transformer. In practice it is expected that 60 – 65 MVA will be used.

The three electrodes descend beneath the burden and the arc is struck continuously between three electrodes. In the arc heat is generated and the reactions occur. The raw materials are reduced by the carbon in the furnace. The overall reaction can be described as:

• Manganese ore is reduced to manganese metal.

• Iron oxide in the iron ore is reduced to iron metal.

• Some of the silica in the quartz is reduced to silicon and becomes a component of the alloy; the rest of the quartz is a flux in the process. The molten flux mixes with the impurities in the coal and ores to form a mobile slag that can be easily removed from the furnace during the slag tapping process.

Two manganese alloys can be produced either FeMn or SiMn.


Carbon monoxide and hydrogen are produced in the reaction which passes through the burden and is drawn off to the gas plant where it is cleaned of tars and dust. The cleaned gas will be sent to Elgen for generating electricity. It will be sent to Elgen or an alternative facility. This is currently being investigated.

3.5 Tapping the Furnace

The furnace bowl is equipped with four tap holes which pass through the furnace shell and the refractory. Two are for slag, and two are for metal. The tap holes are plugged with refractory material called tapping paste while the furnace reaction is proceeding. The tap holes are opened when it is required to remove alloy and slag.

Alloy builds up in the furnace and after 1½-2 hours an approximately 75 MWh of electrical energy has been supplied, 30t of alloy will have accumulated and the furnace is tapped.

The FeMn requires 2.45 – 2.55 MWh per ton of metal, and 30t of alloy are tapped at a time.

There are two pairs of tap holes in the furnace bowl at different levels. The lower pair of tap-holes, one on each side at the front of the furnace, are both used for metal.

The upper pair of tap-holes one on each side at the back of the furnace are both used for slag.

When molten alloy has accumulated in the furnace bowl, the bowl is tapped. A tapping machine drills a hole through the refractory in the tap hole as far as the metal, and the hole is completed using a steel pipe (a lance) through which oxygen is passed. The oxygen burns the alloy and makes the hole large enough for the alloy to pour out. When the furnace is tapped a sample of alloy is taken for testing.

After the hole is made, the alloy pours out of it through a spout into a channel called a “launder” or “runner”. It passes along the runner into a ladle positioned at the end of the runner.

The alloy ladle capacity is 35t; however the operators only tap to a mass of 30t. (Empty ladle mass is approximately 12t).

The furnace is drained of sufficient alloy to just leave a small quantity of alloy below the tap-hole inside the furnace. This alloy left inside the furnace is called a “Heel” of alloy. The tap-holes are then plugged before being used the next time. The tap hole is plugged using a tapping paste from a so-called mud gun. This is the same for slag.

Fume and dust are emitted during the tapping process. The control of these emissions is detailed in Section 5.4.3.


Figure 9: Alloy Tapping into a Ladle at Existing M12 at West Plant.

3.6 Alloy Casting

When the ladles are full of molten metal, they are lifted using an overhead crane and passed to the alloy scales where the weight of the alloy is recorded.

The molten alloy is then passed to a casting bay and poured onto the surface of the previous casting and is allowed to cool and set. The ladle is emptied of the alloy and then returned to the furnace.

Figure 10: M12 Alloy Being Decanted Directly Into the Oxygen Blown Converter (OBC)

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The slag ladle capacity is 60t; however they only tap to approximately 40t. The slag is tapped directly into a large slag ladle which is a device that can be carried by a special vehicle called a molten slag carrier.

The molten slag carrier takes the ladle when full to the Pre Metrec slag stockpile.

Fume and dust are emitted during the alloy and slag casting process. This is captured by the Secondary Off-gas system. See Section 3.8.4.

Figure 12: Slag Being Tapped Directly into a Molten Slag Carrier Ladle.

3.7.1 Emergency Slag Casting

Sometimes there are problems with the molten slag carrier. Under these circumstances slag is cast into a bed in a similar manner to the metal.

Such an operation generates dust emissions:

i. Generating the mould for slag from crushed slag. ii. Casting the slag.

iii. Moving the set slag by the front end loader to the dump truck. iv. Dropping the slag into the dump truck.

It causes more work for the operators because they have to prepare a longer launder. Also it is generally a more onerous slag handling process, with more effort and expense.


Frequency of Emergency slag casting

The plants will strive to ensure that casting of slag into a molten slag carrier happens as much as possible. The availability of the molten slag carrier system is expected to be at least 98%.

In the past the availability of the molten slag carrier has been limited causing emergency slag casting. The molten slag carrier system has recently been upgraded to include new carriers and the availability is now expected to be 98 % minimum.

3.8 Furnace Off Gas Treatment

3.8.1 Primary Off-Gas System

The system for M14 will be similar to the existing M12 Primary Off-Gas System.

Figure 13: A Primary Off-Gas System proposed for M14 .

Like the M12 Primary Off-Gas System the M14 Primary Off-Gas System will be able to cater for a surge of gas as might happen from a furnace eruption. The gas plant must be able to handle such a surge.


Figure 14: Existing M12 Primary Off-Gas System.

Table 1: Furnace Off-Gas Specification The requirements for M14 Primary Off-Gas System are below:

The M14 Furnace off-gas will be rich in hydrogen and carbon monoxide and will be used as a fuel in the gas fired boiler and turbo-generator system of the Metalloys Elgen plant or an alternative electricity generation facility. The gas will however be very contaminated with dust and tar which have to be removed before it can be used.

The gas will be cleaned using water in a venturi scrubber system. This system ensures close contact is obtained between the droplets of water and the gas to scrub out the tar and particular matter (PM).

The Primary Gas Plant will use the similar technology to M12. Two venturi scrubber stages will be used which clean the gases efficiently such that the


emission from the Elgen Plant is invisible and meets the new Air Quality Act requirements.

The gas will however be very contaminated with dust and tar which have to be removed before it can be used in the Elgen boiler.

The buildup of tar and solids in the inlet ducting to the primary off-gas cleaning plant can cause a problem. The ducting will be designed in such a way to obviate the problem as far as possible and a means of easy cleaning of the ducting will be provided.

3.8.2 Sludge

The scrubber water contaminated with tar and PM is sent either to the Pelletising Plant thickener, the NNPDS or the NWPSD where the tar and PM are separated as a sludge. The sludge from both locations is sent to the Pelletising Plant Mixing Facility where it is mixed with other wastes and then converted to briquettes for recycling to the furnaces. Excess pellets can be sold to external parties, there is a market.

The water is recycled to the furnace Off-Gas Treatment Scrubbing Plant.

The pumping of sludge water from the gas plant to and from the dams and at the Pelletising Plant presents is a low risk of pollution. The pipelines will be constructed above ground and any leaks will be detected and repaired before any soil and groundwater pollution can occur.

3.8.3 Dual Redundancy

The Gas Cleaning Plant will be a dual system, one running; one standby with full dual redundancy of the following equipment:

1. Raw gas flare. 2. Inlet water seal. 3. Venturi scrubbers. 4. Cyclones. 5. Gas Plant Fans. 6. Reflux vessel.

3.8.4 Primary Off-Gas Cleaning Plants switch over

The procedure for the M12 gas-plant is as follows:

Should the online Gas Cleaning Plant trip then the furnace transformers are tapped-down to tap one. This reduces the load on the furnaces and the gas production drops correspondingly. The operators then prepare the shutdown gas plant for maintenance and then start-up the second gas plant as follows:

1. The reduced gas flow from the furnace is passed to the raw gas flare. 2. The water seal is filled to isolate the tripped Gas Cleaning Plant from the

furnace.


3. The second Gas Cleaning Plant is then checked to ensure it is ready for operation after maintenance. This takes 30min.

4. The second Gas Cleaning Plant is then purged with inert carbon dioxide gas from storage until the oxygen level in the plant is at a satisfactory level to introduce furnace gas. This typically takes 55 minutes.

5. Power is turned on to the furnace and slowly increased. The gas generated sent to the raw gas flare this would continue until the load reaches 25MW. At that point the water seal on the second gas cleaning plant is drained and the gas cleaning plant processes the gas, sending it to the Electricity Generation Plant (Elgen).

6. The total time for the switch over of the plants is 1½ hours. It work has to be carried out on the /2 the second plant the it will take correspondingly longer.

Ref Metalloys Standing Operating Procedure West Plant No 25.

The only predictable time that the gas plant would not be used is if the furnace is on low-load, generally after start up from shut downs and during shut downs.

On low-load the circulation of the gas through the plant is very high compared with the flow into the plant and there is the risk that air could be sucked in through one of the seals, and it is safer to shut it down for that short period.

The cleaned gas from the M14 Primary Off-Gas System will be pumped by means of fans to the Elgen plant. where it is combusted in a boiler to generate steam and then electrical power to feed the factory grid.

If Elgen has to shut down for any reason the clean gas will be flared to atmosphere at the Plant.

Stack Monitoring

The clean gas stacks will have instrumentation that will continuously monitor and record the concentrations of:

1. Carbon dioxide 2. Carbon Monoxide 3. Hydrogen 4. Oxygen 5. Particulate matter is being considered if technically feasible.

3.8.5 Availability of the Primary Off-gas Cleaning Plant

The vendors of the M14 Primary Off-gas Cleaning Plant state that the startup of the plant would take a maximum of two hours.

The plant will be much more flexible than the existing M12. The plant capacity will be in the order of 30 or 40 000 m3/h this has still to be finalized with Metalloys.

The plant will be capable of being turned down to 20% of full capacity.


With these improvements it is expected that the availability of the M14 Primary Off-gas Cleaning Plant will be greater than 99%.

The operation of the gas cleaning plant is difficult. An availability of 99% however should be possible provided that:

1. The plants are properly maintained and always in a state of readiness for start-up.

2. The operators are trained to carry out a the operations required for start-up of the gas plant . There should be programmes for retraining and refresher training in place.

3. There is sufficient trained manpower to carry out the startup. 4. There are proper procedures in place to carry out the startup. 5. That a productivity improvement plan (PIP) be implemented to

continually improve the operation of the gas cleaning plant.

The on-going availability of both off-gas cleaning plants will be monitored by HSEC.

3.8.6 Further Improvements in the Primary Off-Gas Plant - Sumps

The sumps will be placed above ground with the intention of identifying leaks, and avoiding pollution of soil and ground water. The sumps of the Primary Off Gas Plant will be within a plant bunded area.

3.9 Secondary Off Gas System M14 Furnace Fugitive Gas and Fume Extraction

All of the operations of tapping, conveying of molten alloy and slag to the ladle, pouring into the ladle and casting of alloy generate fugitive emissions of fume and dust. Fume extraction equipment vendors are designing a new hood system around these points of the M14 Furnace. At each of these operations there will be hoods connected to extraction ducts to remove the fume and a considerable amount of air. This will minimise fugitive emissions from tapping, and casting operations.

As with the M12 Furnace there is a smoke hood over the furnace to capture fugitive emissions from electrode holes etc.

Hoods are being placed over the nine casting Bays which serve M14.

All of these dust and fume extraction points are connected to a bag-house system which will remove 26% more air and fume and dust than the existing M12 Furnace Secondary Off-Gas System.


Figure 15: Existing M12 Secondary Off-Gas Bag-houses.

Figure 16: M14 Smoke Hood Fume Extraction

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The increased flows of air extracted from the various furnace areas are as follows:


3.9.1 Smoke Hood – Carbon Monoxide

The carbon monoxide level at the smoke hood could be in the order of 20 to 30% by volume. Significant dilution air is taken in at the hood and the additional dilution from the rest of the extraction system gives a concentration at the baghouse of 2.9%.

The lower explosive limit of the gas is 12.5%. This means that any concentration less than 12.5% will not be explosive.

Therefore in the case of M14 off gas system the calculated figure of 2.9% is well below the lower explosive limit. See Ref 10.27.

3.9.2 The Bag House

The ducting passes to the secondary pollution plant where the air is filtered with bag filters and after having been filtered by the filter bags, passes through a fan, which draws the air into the filter plant, before passing it to atmosphere. The M17 Bag-house will be used for this in which case it will be released through a stack at a height of 38.5m. The bag-house will be upgraded by the addition of two new compartments to the existing six.

3.9.3 Fan availability

Two fans will be required to generate the required flow of 626,400 Am3/h. A spare impeller/shaft assembly will be held as a replacement should it ever be required. If one fan is to be shut down for repair or maintenance, the single fan is capable of handling approximately 65% of the new total volume.

It is estimated that to replace the impeller will take a maximum of one day. See Ref 10.27

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The study was carried out by emission monitoring specialists. . See Ref 10.22.

Using this information, a system has been designed to capture these fugitive emissions.

The following is the preliminary list:

Freestanding de-dusting units at the fugitive emissions points are to be considered. A total of thirteen units will be employed, they are listed below:

a. One unit on the proportion bins rotary conveyor head chute. b. One unit on each of the 5 weigh hoppers. c. One unit on each of the 5 belt feeders. d. One unit on the WEBA transfer chute. e. One unit on the furnace feed rotary conveyor head chute.

See Appendix 11.40.

3.9.7 Secondary Bag House Dust

The bag houses of M14 will generate approximately a further 80 t/annum.

This bag filter dust is collected and despatched to the mixing plant of the Pelletising Plant where some of it is combined with sludges and other materials. It is pelletised and recycled as feedstock for South Plant Furnaces. For details of pelletising, see Pelletising Plant Section 2.4.1.

3.10 The Furnace Pressure Relief

The furnace is protected against over pressuring, by means of the following:

a. Capacity of the Primary Gas Cleaning Plant.

The Primary Gas Cleaning Cleaning Plant has more than twice the capacity required to handle the design rate of gas produced. This means that most surges of gas that could be generated can be handled by the gas plant.

b. Mushroom valves

In the event of a surge being greater than what the primary gas cleaning plant can handle then the excess gas will pass through mushroom valves.

Mushroom valves are water seals set at a level higher than the suction generated by the Primary Gas Cleaning Plant.

The hot gases from the mushroom valve will be directed to a elevated safe location outside of the plant area by means of ducting.

c. Explosion panels

In the unlikely event of an explosion of occurring inside the furnace then the shocks of the explosion will release specially designed panels to relieve the pressure and shock of the explosion.


3.11 Cooling Water Systems

Two Closed Circuit Cooling Water (CCCW) systems will be used for M14. In such systems water is circulated from a tank through pumps through a cooling tower and to the various parts of the furnace that require cooling. The hot water returns to a tank.

The CCCW system is not open to the environment. . In the CCCW system the water is in a closed system with all pipes above ground and not exposed to the environment.

Should any leaks occur they will be repaired as soon as they are identified.

Losses occur because of evaporation. The level in the tank is maintained by RWB water which is treated by a softener; salt is used to regenerate the water softener. Regeneration water and rinse water pass into the sludge water system. The process and public water circuits are kept separate so there cannot be any contamination of RWB water.

For both CCCW systems there will be appropriate dosing to minimise corrosion and fouling and will include biocides for biological risks such as Legionnaire’s Disease.

There will be two CCCW systems at M14:

i. Cooling for the furnace equipment: electrode system, electrical and other furnace equipment.

ii. Cooling for the furnace shell.

CCCW for electrical and other furnace equipment Systems

The Closed Circuit Cooling water is used for the following:

i. The furnace roof. ii. The contact shoes.

iii. The pressure rings. iv. The Doorposts.

CCCW for the furnace Shell

Water will be pumped to the top of the furnace and pass over the furnace shell and then be collected at the bottom and pumped to the cooling system. See above.

Flow rates m3/h Circuit Makeup CCCW – Furnace Equipment m3/h 614 24 CCCW – Furnace shell m3/h 220 24 See Ref 10.19.

3.12 The Control Philosophy of the M14 Furnace.

The main furnace and auxiliary equipment will be controlled by a distributed control system (DCS) and/or programmable logic controller (PLC), with monitors and controls within a central control room.

The primary control of the M14 Furnace is resistance control of the arc between the electrodes. The secondary control is current control by the transformer. The Secondary voltage is controlled by furnace transformers and electrode tip position.


3.12.1 Resistance Control of the Electrodes.

This is achieved by raising and lowering the electrodes in the furnace bed to control the resistance. The electrodes are anchored to a collar which has hydraulic lifting equipment. If the resistance becomes too high the electrodes are lowered into the furnace bed and vice versa.

Controlling the resistance this way enables a constant current and a stable furnace operation.

3.12.2 Slipping the Electrodes.

During furnace operation the Electrodes are burned away and to make up for this they are lowered. After a while they cannot be lowered any more and have to be slipped. This operation is independent of the resistance control above.

Each electrode is held by two clamps one above the other. To slip the electrode the top clamp is released and raised and reclamped. The bottom clamp then is released and the electrode is moved down through the bottom clamp.

The furnace control system measures resistance between the electrodes and a hydraulic system raises and lowers the electrodes to keep the resistance constant as per the operating set point.

At the top of the furnace, electrodes are being continuously fabricated to enable this slipping process to occur. See Soderberg electrode system. Section 3.4.

3.12.3 Raw Materials

As Mn alloy is produced, so more and more raw material is consumed. The raw materials are contained in feed bins with chutes that descend to the surface of the burden in the furnace. As the furnace consumes raw material it is automatically replenished flowing down the chutes by gravity to the surface of the burden.

3.12.4 Power factor

The furnace operates with a three phase electrical system. The circuitry and equipment has a high and variable reactance which influences the power factor. The addition of large capacitors in the circuitry can have some influence on restoring the power factor and good efficiencies can be achieved. However it is expected that the furnace will have to operate with a power factor of 0.65. This means that a supply of 61MVA will provide a load of approximately 43MW for the furnace. The balance of energy will be the losses in the furnace equipment and will appear as heat.

3.13 Manpower

3.13.1 Construction

Temporary Construction engineers, management and artisans will be employed for building the plant. The numbers employed will vary throughout the construction period peaking at 400 in total.

Most will be sourced locally.


3.13.2 Normal Operation

Once the plant has been constructed and commissioned and continues with normal operation the following people will be employed:

Supervision Share M12/OBC shift supervisor. Operations per shift

• Tappers 3 • Operators 2 • Crane Operator 1 • Runner preparer 2

Total per shift 8 Total for four shifts 32 Maintenance • Artisans No Extra • Maintenance Engineer. No Extra Current 61 Security 4

Total new employees 32

Most will be sourced locally.

No further maintenance staff will be recruited, and the extra maintenance work required for M14 will be achieved by an increase in productivity through good practice and planning.

3.14 Plant parameters

The Plant Footprint

Furnace Height: 44.4m. Length: 34m Width: 32m Area: 1080m2


Figure 19 Plot Plan of the Furnace Area

Key to Plot Plan 1. Plant Access Control to Be Relocated. 2. Carbon Store to Be Dismantled. 5. Primary Off-Gas Terrace. 6. Pump Station for Furnace Shell Cooling. 7. Equipment Cooling. 11. Cooling Water Tank. 12. Extension to Compressor House - MCC Room. 14. Secondary Off-Gas Bag-House


Associated plant and equipment

• Provision for the Primary Off-Gas plant is 48m x 18m and 25m x 18m for sludge water plant. This is based on M12, however pending technology selection this could potentially change and it may be smaller.

• Secondary off-Gas – Will require an extension of an additional 2 compartments. It will be within the existing footprint of 74m by 22m.

• Casting bays/beds fume extraction will be tied into Secondary off-gas plant. • Paste Stores for M12 and new M14. M12 is presently 30m x 15m to be

extended by 15m x 5m, totalling 35m by 15m. • Ladle heating area will be moved to be under existing roof area where the

ladle repair area is. The size is 26.6m by 13.7m. • Ladle repair area to be moved to a new extension of the building. • A new control Room (27m X 17.5m) – not part of this project will be built by

West Plant, and will be used by M14. • New Offices - 30m x 27.7m – also not part of this project, will be built by

West Plant, and will be used by M14.

3.15 Project Responsible Parties, Design Guidelines and Construction Codes

M14 will be a replica of M12. The design will have certain new developments including a new electrode system. See Section 3.4.

A project team has been set up with a Steering committee of senior Factory Management. See below and Appendix 11.37.

a. Project Management

Project Sponsor Christiaan Cornelius Jordaan General Manager

Technical Manager Ferdus le Roux Engineering Services Manager Tribe Bhengu Process Steynberg Janse van Rensburg Project Manager Grant Taylor

b. Design guidelines

Minimum standards will be those provided by SANS, the Occupational Health and Safety Act, and BHP Billiton standards; other standards will be generated as the project proceeds which will be site specific.

c. Technology Provider

The technology is based on that of the M12 Furnace and M14 will largely be a duplicate of M12 with substantial improvements.

d. Hazops and Further Studies

The M14 project has been subjected to a Hazop. Several other studies will be considered to be carried out including other Hazard studies. See Appendix 11.36.


4 BEST AVAILABLE TECHNOLOGY. (BAT)

The European Union Integrated Pollution Prevention and Control (EU IPPC) document provides details of BAT that is relevant for this industry:

a. BAT for the electric arc furnace (EAF). EU IPPC Production of Iron and Steel Chapter 9 See Ref 10.8.

b. BAT for the Non-Ferrous Metals industry Chapter 9. See Ref 10.16.

Information from BAT documents is in italics.

4.1 BAT from the Production of Iron and Steel

Techniques to consider in the design of the EAF for the determination of BAT from Ref 10.8. EU IPPC Production of Iron and Steel Chapter 9 are listed below:

Process-Integrated Measures:

PI.1 EAF Process optimization.

a. Ultra high power operation b. Water cooled side walls and roofs. c. Oxy fuels burning and oxygen lancing. d. Bottom tapping system. e. Foaming slag practice. f. Ladle or secondary Metallurgy. g. Automation.

PI.2 Scrap Pre-heating.

PI.3 Closed loop water cooling.

End of Pipe Techniques

EP.1 Advanced emission collection systems.

EP.2 Efficient Post Combustion in Combination with advanced off-gas treatment.

EP.3 Injection of lignite coke powder for off-gas treatment.

EP.4 Recycling of EAF slags.

EP.5 Use of bag filters.

Each of these will be considered in turn:

PI.1 EAF Process optimisation.

The most important techniques considered are as follows:

a. Ultra high power operation.


Applicable to a DC furnace only; not applicable to Metalloys SAFs.

b. Water cooled side walls and roofs.

Water cooled side walls and roofs will be employed. It will result in reduced refractory wear and enable the ultra high power operation above.

c. Oxy fuels burning and oxygen lancing.

Not applicable.

d. Bottom tapping system.

This system will be employed.

e. Foaming slag practice.

Not applicable.

f. Ladle or secondary Metallurgy.

Not applicable.

g. Automation.

M14 will employ Scada (PLC) central Computer controls. This will provide interlocks for safe operation, and optimize the three phase DCS control system for the single phase transformers.

PI.2 Scrap Pre-heating using EAF off-gas.

In the M14 SAF there is a deep burden of about 3m. The reaction gases escape by passing through this burden. In this way the raw materials are heated and there is some recovery of the waste heat.

PI.3 Closed System Water Cooling

The M14 Furnace will be cooled by a closed circuit water cooling system. This is in turn cooled by fin-fans.

End of Pipe Techniques

EP.1 Advanced Emission Collection System

M14 is a closed furnace, and will therefore operate effectively as a “fourth hole in the hood” direct extraction system. This is the most favoured BAT. This minimises fugitive emissions.

EP.2 Efficient Post Combustion in Combination with advanced off-gas treatment.

The M14 off-gas contains Carbon monoxide and hydrogen. This is used at the Elgen plant to generate power.

EP.3 Injection of lignite coke powder for off-gas treatment.

Not applicable.


EP.4 Recycling of EAF slags.

Metalloys are advancing other options to use the Mn alloy slag.

EP.5 Recycling of EAF dusts

The dusts from the primary and secondary dust filters will be recycled by pelletising and recycling to the South Plant.

EP.6 Use of bag filters

Bag filters are used extensively throughout the process for many of the point source emissions. Typically bag filters emit cleaned gas containing 15 - 30mg/m3 of PM.

4.2 BAT from The Non-Ferrous Metals Industries

Ref.11p EU IPPC Non-Ferrous Metals Industries Chapter 9.

4.2.1 Off Gas Collection Techniques.

The process steps involved in the production of Mn alloy involve the potential production of dust, fume and other gases from the processing. Gases and fume that escape from the processes are released into the working area and then escape into the surrounding environment. They therefore affect operator health and safety and contribute to the environmental impact of the process.

4.2.2 Techniques Applied in the M14 Design

Process gas collection techniques are used to prevent and minimise these fugitive emissions.

Dust, fume and gases are collected by using hoods which are designed to be as close as possible to the source emission while leaving room for process operations. Movable hoods are used in some applications and some processes use hoods to collect primary and secondary fume.

4.2.3 Use of energy

Gas collection requires the movement of significant volumes of air. This can consume large amounts of electrical power and modern systems focus the design on capture systems to increase the rate of capture and minimise the volume of air that is moved. The design of the collection or hood system is very important as this factor can maintain capture efficiency without excessive power consumption in the remainder of the system.

Ducts and fans are used to convey the collected gases to abatement or treatment processes. The effectiveness of collection depends on the efficiency of the hoods, the integrity of the ducts and on the use of a good pressure/flow control system.

The extraction of fume will be scheduled to correspond with tapping, and carried out to maximize the capture of fume. This approach will minimize the volume of gases moved with corresponding lower energy requirements.


4.2.4 Other Techniques to consider

An important established practice to achieve good extraction is the use of automatic controls for dampers so that it is possible to target the extraction effort to the source of fume without using too much energy. The controls should enable the extraction point to be changed automatically during different stages of the process. The extraction point should also be designed to allow good access to the furnace and give a good rate of extraction. The hooding should be constructed robustly and maintained adequately. Maintenance of the collector hood, the ducts, the filter system and the fan is vital to ensure that collection or extraction rates remain at the designed level.

4.2.5 Fugitive Emissions

Good extraction is used to prevent fugitive emissions as illustrated above but some systems cannot collect all of the process gases and they are emitted into the workspace and are then collected by the furnace hood, and passed to the secondary off gas bag-house before being passed to atmosphere.

Fugitive emissions can be highly significant, therefore if fugitive emissions cannot be prevented or minimised to an acceptable level, secondary fume collection systems can be used as follows:

• Furnaces can be equipped with secondary hoods in order to prevent fugitive emissions during charging or tapping as described above. The fan suction is provided directly at the source of fume to optimise the reduction of fugitive emissions. Alternatively, the air could be extracted at the roof ventilator, but a large volume of air would have to be handled which might not be cleaned effectively in a fabric filter. Other disadvantages are high energy consumption, high investment, more waste (used filter media).

• Secondary fume collection systems are designed for specific cases. Energy use can be minimised by automatically controlling the point of extraction using dampers and fan controls so that the systems are deployed when and where they are needed.

• The de-dusting equipment is composed of various hoods located above the tap hole of a blast furnace. This can also be applied to a SAF. The main alloy runner, and the device where the liquid alloy is poured into the ladle. The collected fume is cleaned in a separate bag filter. The hooding system (viewed from the top of the blast furnace) is shown in the following figure.

M14 will have carefully designed closely fitting hoods and damper control. Also a smoke hood above the furnace will capture fugitive emissions. Both these emissions pass to the secondary off-gas system for filtration before release to atmosphere.

The fugitive emissions will be quantified and dispersion studies will be carried out to determine the impacts on the community and the environment. See Section 5.4.3.


Figure 20: Tap-Hole Fume Collection as Applied to a Blast Furnace.

4.2.6 Face Velocity

Discussions with a gas cleaning system vendor (Ref 10.17) have indicated that the extraction system should be designed so that the gap between the hood and the emitting component eg the ladle or the runner should be as small as possible, that the extraction fan draws the air such that it generates a velocity of 2m/sec in the gap (Face velocity). This would enable capturing of the fume and virtually eliminate fugitive emissions.

The temperature of the gas must be considered and maybe monitored to ensure the gas does not damage the bag house.

5 SAFETY HEALTH AND ENVIRONMENTAL ISSUES

5.1 Safety

5.1.1 Heat

Temperatures up to 1450oC are involved in the process and accordingly heat stresses will be present at M14. Heat stress levels for various parts of the plant will be similar to M12.

The areas with a heat stress risk are around the tap-holes, launders, ladles, pots and layer casting pits and slag pit. A similar plant had a heat stress survey carried out as part of a hygiene study and should serve as guidelines till M12 provides more details. The data are below:


Table 3: Temperatures in the Furnace Plant

5.1.2 Chemical and Material Hazards.

All raw materials, products and wastes used in the process are listed in the chemical hazard pro-forma, and all hazards associated with these substances are listed.

See Appendix 11.1.

The process also uses many auxiliary chemicals. These are under the following a main headings:

a. Maintenance materials. i. Lubricants.

ii. Paints. iii. Maintenance reagents, eg Crack detection chemicals, iv. Metal materials for construction. v. Process chemicals e.g.

i. Biocides. ii. Water treatment chemicals.

iii. Fan detarring chemical. b. Fuels.

i. Gaseous. ii. Liquid.

iii. Solid. c. Raw Materials.

All the above have MSDSs which are on file for ready access.

All operators are trained in the use and hazards of the above chemicals.

There are no new substances which Metalloys is not familiar with. The main concerns with chemicals are the risk of manganism from inhaling dust of manganese containing materials and Silicosis from inhaling quartz dust.

Area

Measured natural dry-

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Measured natural wet-

bulb temperature

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WBGT index

Furnace Area 24.5 25.5 18.7 20.7

Furnace Area (While tapping) 30.4 31.6 21.1 24.5

Cooling down area 23.6 24.2 19.2 20.7

Control Room 21.1 21.9 14.0 16.4

Raw Materials 26.0 26.0 18.0 20.4


5.1.3 Risk areas of Operation

Detailed management requirements are contained in FRCS’s. See Section 5.5.2.

Furnace Operations

Hazards are caused by certain abnormal operating conditions. These can cause high costs and risk injury and fatality to personnel if proper procedures are not followed.

A Risk Assessment has been carried out and the main areas of concern are:

a. A burn through - for this the focus is efficient shell cooling. b. Water explosion - for this the focus is:

i. Water loss detection -dual water flow meters. ii. Monitoring hydrogen content of the off gas.

c. Furnace eruptions also See 2.1 on lumpy feed. d. Crane operation of lifting Ladles of Molten material.

Following the Risk assessments carried out by the Metalloys HSEC Department, Procedures have been written covering every operation, and are constantly reviewed and modified to reduce this risk to an acceptable level.

The operators are trained and provided with specific instructions for their tasks and given the correct PPE. In the case of the crane operations, special care is used in carrying out the function and the operators are trained and licensed and have the correct PPE. See Section 5.3.5.

5.2 Health

5.2.1 Silica

Silica as crystalline quartz is a raw material. It is also present in the slag in the form of a fume.

The health effect of exposure to quartz (silica dust) is silicosis and acute silicosis when exposed to silica fume.

Quartz dust generates the health hazard of silicosis.

5.2.2 Dioxins

For information on dioxins and their formation see Appendix 11.38.

Dioxins Formation in the M14 Furnace

There is little to be found in the literature about dioxin formation in the submerged arc furnace, although there is information about dioxin formation in an electric arc furnace used for processing scrap.

It seems that there is a likelihood of dioxin formation if the feed to the electric arc furnace is mixed with scrap material. The scrap contains plastic and oil, all which contribute to the formation of dioxins.


In SAF manufacture of Mn alloy where the materials are supplied directly from the mine, with no impurities of plastic or oil, then it is likely that the formation of dioxins will be limited and emissions will be below the International accepted standard.

If there is a likelihood of the synthesis of dioxins in the Mn alloy furnaces then there are various techniques that could be employed depending on the application, to be incorporated into existing processes. The most effective and economically viable technique will depend on the specific site, safety aspects and operational stability as well as economic factors taken into account. Emission levels of better than 0.5 ng/m3 TEQ can be achieved using one or more of these techniques to the clean gas side of the system. Lower values better than 0.1 ng/m3 TEQ can be achieved by one or a combination of these techniques should it be necessary.

A desk study will be carried out of the proposed M14 Furnace to determine the magnitude of D&F generation in that process. If necessary a sampling campaign will be carried to confirm the findings.

5.2.3 Polycyclic Aromatic Hydrocarbons. (PAHs)

PAHs are also known as coal tar volatiles. They are carcinogenic chemicals. Small quantities are generated from the following:

a. Electrode Paste.

As the Electrode paste bakes it generates fume which may contain PAH. This shows itself as a small plume of fume wafting from the top of Electrode mantle. This part of the Electrode will be in a well ventilated area and the fume will disperse into harmless concentrations.

It will be monitored however, to ensure that it will not generate any occupational health problems.

b. Taphole mud.

If a carbon based taphole mud is used, PAHs could be generated during tapping. It will be also be monitored, to ensure that it will not generate any occupational health problems.

5.2.4 Carbon Monoxide

There will be local CO monitors on all floors as well as restricted access to risk areas/floors, managed via the site access permit system/procedures. Here portable CO monitors are issued to staff moving into these areas. There are also rescue packs i.e. emergency respirators on each floor for potential incidents.

5.2.5 Dust

Dust will be present in almost all operations of M14. In particular raw materials handling, the SAF, molten product handling, molten slag handling, product crushing and emergency slag casting and the breaking up of solid slag and its handling.

5.2.6 Noise

The current noise levels of M12 are listed below:


Table 4: Noise levels for the various parts of the plant

Appropriated PPE will be used to protect the operators in these areas.

The main concern is the fans from the Secondary Pollution Plant. It will be upgraded to give better performance. See 3.8.6.

It will have a high noise level (>85dB(A)), and have to be demarcated as a noise area requiring ear plugs or muffs.

The vehicle transport will also generate noise and dust and is the subject of a separate study.

5.2.7 Aesthetics

Only the primary off Gas plant will be visible outside the West plant building, and it will be lower than the current buildings.

Some light will be emitted from this but it is not expected that this will cause any visual intrusion.

The design of the new buildings will be such that they will merge in with the existing structures.

Considerable amount of effort has been put into planting grass in the area; this has the bonus of capturing fugitive dust and stopping it being blown away again.

5.3 Working Environment

5.3.1 Dust

Dust concerns come from the three following areas:

a. Process dust. b. Tapping of the furnaces. c. Fugitive dust from material movements and truck movements.

Dust monitoring is carried out in a similar manner to the noise monitoring. Selected operators based on hygiene programme carry static dust monitors and the amount of


dust that they are exposed to is monitored, this information is used as general input for identifying dust zones and modifying the plant to reduce the dust.

Raw Materials Handling and SAF and Product Handling

Dust is a major problem from raw materials handling, SAF operation and product handling. The plant will be equipped with extensive dust extraction units to limit the dust concentration in the working environment. However it is expected that dust masks (BHP Billiton Standard PPE) will still have to be worn in the furnace area.

5.3.2 Noise

All operators including the M14 operators are exposed to certain levels of noise. See 5.2.5 above. Hearing protection will be required in the furnace area.

Noise surveys are carried out on the plant to identify noise areas; and some monitoring is carried out continuously. Trials are carried out where operators carry noise monitors, which measure the levels of noise they are subjected to in the different areas of the plant. Main areas of concern will the secondary pollution plant, because it may have noisy fans. The dampening of these fans to reduce the noise emitted is being investigated.

The personal monitors are carried for organised periods by, e.g. the crane drivers, tappers, operators, etc, who are exposed to noise.).

Noise areas are demarcated and marked with statutory signage.

5.3.3 Heat stresses

There are areas of the M14 which will be very hot operations. These are tapping, the runners and ladles, and casting. These will be inaccessible for operation without appropriate PPE. An area will be demarcated as hazardous zones and training will ensure these are enforced and that appropriate PPE is worn. See OHS Management below.

Most operations however will be carried out remotely using hydraulic systems. When operators have to work close to high temperatures, then the proper PPE will be used.

A hazard with an SAF is the tap holes. Here an operator has to open the tap hole using a tapping machine, and burn the solid alloy in the tap hole with an oxygen lance, and he has to do this just a few metres away posing a risk of injury. Experience and training and operating procedures and the correct PPE have reduced this risk to acceptable levels.

Heat Stress Monitoring - Occupational Hygiene Programme

The programmes in place with regards to the management of heat stress work.

a. Heat Stress monitoring:

The levels and control measures have been highlighted and the plant has implemented them.

b. Medical Surveillance Programme:


This is an additional control measure, and uses a specific protocol that is called Thermal Stress Protocol.

The Thermal Stress Protocol is used in the selection of employees who will be working in heat stress areas as well employees who are already working in those areas. The protocol comprises of a physical examination as well as a questionnaire that looks at the person’s medical history.

Plans for the future:

a. Ergonomic assessments in all the plant areas – including West Plant and the issue of heat stress management has been carried out. . Implementation is currently in progress.

a. Providing training in relation to heat stress management.

For details of the measurements see Ref 10.23.

5.3.4 Other Physical stresses in the working environment

a. Lighting surveys are carried out 2 yearly and modifications are made. b. Ionising radiation: there is no ionising radiation equipment at West Plant. c. Ergonomic, these studies are in the process of being done.

5.3.5 Personal Protective Equipment (PPE)

The following PPE will be required:

Everybody:

i. Hardhat. ii. Safety glasses.

iii. Denim overalls. iv. Safety boots with steel tips. v. Earplugs or earmuffs.

Areas with heat stresses:

vi. Leather gloves. vii. Leather spats.

viii. Leather apron. ix. Heat-resistant visor for work in the casting bay. x. Safety boots with steel tips and heat-resistant soles.

xi. Long woollen coat.

Also see Section 5.5 Occupational Health, Safety and Environmental Management.

5.3.6 Medical Facilities

a. There are trained first-aiders on every shift. b. There is an occupational health medical centre and clinic, which is outsourced.

It has four nurses and a doctor visiting and on standby. c. There is a Dedicated Medical Emergency Response Supplier based in the

hospital at Vereeniging.


5.3.7 Risk assessments

A considerable amount of work is being carried out with risk assessments for the site generally regarding exposure of employees to the various aspects of the working environment. See Ref 10.10.

5.4 Environment

5.4.1 Solid Wastes

a. Mn alloy Slag.

b. M14 will generate 120 000t/a of Mn alloy slag which will be dumped at the Pre Metrec slag stockpile.

c. Furnace dust.

It is intended that the furnace dust from all the furnace bag-filters will be pelletised and recycled to the South Plant furnaces or sold.

There will be intermittent furnace rebuild and maintenance wastes. This will be carbon steel, alloy steels and refractory.

Leachate

All of the SiMn slag heaps and the FeMn slag heaps and the bag-house dust, stockpiles and raw material stockpiles generate a leachate. This has been quantified to some extent. See Ref 10.24. However impact on ground water will only be established when the numerical model has been computed during the internal Waste Water Management Plan (IWWMP) Phase 2 Project.

5.4.2 Liquid Effluents

Although cooling water is used, it is in two CCCW systems one for the furnace shell and the other for electrical and special furnace equipment.

Heat is removed from the system by means of fin-fan coolers. There is no blow-down and normally no liquid effluents. There maybe infrequent dumping of the water for maintenance reasons. This water will go to the gas sumps to the NWPSD

Water Balance

Water consumed in the process:

Rand Water

Potable Water m3/h m3/a

a. M14 CCCW system – electrical 24 203 933 b. M14 CCCW system – Furnace shell 24 203 933 c. Offices, Ablutions, Change rooms 1 8 497


Figure 21: Water Balance

7 279 0.44 t/h3 711 t/a

m3/h

0.44 t/h3 739 t/a

24.00 t/h24.00 t/h 203 933 t/a

203 933 t/a 588 t/h

24.00 t/h 306 t/h 24.00 t/h203 933 t/a 203 933 t/a

0.00 t/h0 t/a 0.00 t/h

0 t/a

1.00 t/h8 497 t/a 1.00 t/h

8 497 t/a

49.44 t/h

49.44 t/h TOTALS IN Balance TOTALS OUT 49.44 t/h

420 126 t/a 0.00 420 074 t/a

Availability 0.97 1.00 t/hFactor M t/a : t/h 8 497.20 t/a

420 073.87


Closed Circuit Cooling Water (CCCW) Treatment.

The CCCW is topped up with Rand water and treated with the following dosing chemicals:

BUSPERSE® 2060 Dimethylamides in solvent. BULAB® 9334 Zinc compounds. BULAB® 9157 Nitrites. BULAB® 7086 Acrylates. BULAB® 6038 Bromine compounds. BULAB® 6026A Ketones and derivatives. BULAB® 6019 carbamodithioic acid, dimethyl-, sodium salt.

MSDS documents for all the above chemicals are available in the plant information system.

Should it be necessary to dump the CCCW for say maintenance purposes, then it will be pumped into the sludge water system.

Primary Off-gas Scrubbers.

The off-gases are cleaned by scrubbing them with water in two venturi scrubbers.

The clean gas leaves the plant and passes to the Elgen plant. It is saturated with water at approximately 50°C.

The water in the scrubbing system is made up by water from the Amcor dam and controlled by North plant. They monitor North and West Dam levels and keep them topped up.

21 000m3/a of water is currently sent to Elgen plant from M12 as water vapour in the gas; this is made up by water from Amcor dam along with natural evaporation.

An equivalent amount will come from M14 and west dam will have to be topped up from Amcor dam.

The M14 off-gas fan seals are carbon and require no water as a seal liquid.

Storm-Water

M14 will be built in the existing West Plant. It will not result in any further significant contamination of storm water.

The clean storm-water will be routed to storm-water drain where it will find its way to the Amcor dam. None will flow into the Fourie Spruit or the Klip Rivier.

5.4.3 Gaseous emissions

See Waste Block Diagram Fig 5.


The main point source gaseous emissions will be from the secondary pollution plant, and the clean gas stack, if the clean gas is not being sent to Elgen, and the raw gas stack if the gas plant is shut down.

Fugitive emissions are generated by furnace operations and furnace raw materials handling and product handling. Associated fugitive emissions are generated by raw materials, product, and waste handling outside the furnace area.

WG3 – Secondary Pollution Plant.

The secondary pollution plant captures fume and dust that is generated from emissions from the furnace area. These emissions are generated mainly from the handling of molten alloy and slag.

Furnace Fugitive Emissions

Fugitive emissions arise as a result of furnace activities See Section3 and Fig 5:

WG7 Tapping the furnace to release the molten metal; the running of the molten alloy in the launder into the ladle.

WG2 Tapping the furnace to release the molten slag, the running of the molten slag in the launder into the ladle, and pouring the slag into the molten slag carrier.

WG8 The casting of the molten alloy into the slag casting bed, its collection by slag collection contractor when solid, and the preparation of a new casting bed.

WG5 The emergency casting of the molten slag into the casting bay. WG9 The pouring of the molten alloy into OBC.

Hoods will be positioned over these activities, which are connected to ducting, which eventually passes to the secondary pollution plant. Suction from the secondary pollution plant draws fume and dust from the emissions. The critical consideration in this operation is the efficiency of the hoods and ducting to draw away the fume and dust. Some of the fume and dust will escape the hoods, form a fugitive emission, and pass into the working environment and eventually pass out of the building and into the atmosphere surrounding the site.

The hoods and ducting will be designed to ensure that the maximum practicable extraction will be achieved. See Section 3.9 and Section 5.4.4. The efficiency of the hoods of the dust and fume extraction equipment will be studied. How much of the dust and fume is collected, and how much is released to the building forming a fugitive emission to atmosphere will determined. The study cannot be completed until the detailed design of the furnace is carried out.

However the vendors of the equipment have given an indication of the efficiencies that can be expected. See Section 5.4.4.


The fugitive emissions are quantified using both emission factors and dust removal efficiencies. The emission factors are from US EPA See Ref 10.11 and Ref 10.12.

The impacts of these fugitive emissions on the environment and the community at large are being quantified by the dispersion study specialists and toxicologists.

Associated Fugitive Emissions

Raw material handling

The raw material handling plant will be equipped with stand alone de-dusting units positioned in strategic places to capture the dust emissions from raw material movements.

M14 will consume the following raw materials:

RM1 Manganese ore - Nchwaneng (Assmang) High Grade Ore (NHO).

RM2 Manganese ore Mamatwan Lumpy Ore (MMT) (M1L). RM3 Manganese ore Mamatwan High Grade Sinter (MHS). MHS

may not be available when M14 is commissioned. RM4 Manganese ore Mamatwan Medium Grade Sinter (MMS). RM5 Iron Ore. RM6 Manganese ore – GEMCO. RM7 Quartz. RM8 Chinese Coke. RM9 Mn alloy briquettes. RM10 Coal. RM11 Anthracite.

Fugitive emissions are generated with the handling of each of these RMs by MMD from the raw material yard to the furnaces on the site. M14 will proportionally increase these fugitive emissions.

Fugitive Emissions from Product Handling.

WG10 Mn alloy alloy product (P1) collecting, crushing, screening and dispatch.

Other Fugitive Emissions

WG6 The casting and quenching of slag at the stockpile by molten slag collecting contractor, and the crushing and handling of the solid slag.

WG4 The handling of bag house dust and its dumping.

These fugitive emissions will increase proportionally with the increase production of M14.


All of these emissions WG1 to 10; RM1-9 and P1-P6 are dimensioned in the Appendices 10.2 to 10.34.

Dust from Road Transport

Fugitive dust will be emitted from materials handling by road transport. The dust content of all materials and PSD must be determined and the dust content on the roads and dampening procedures obtained.

M14 will increase the Raw Materials Handling from transport dust emissions proportionally by the amount of Raw Materials it consumes. This is being quantified by the dispersion study specialists.

Public Risk

Main concern for the public is emissions of particulate matter impacting upon them.

5.4.4 M14 Emissions – Dispersion Study

Full details of the Primary and Secondary Off-gas Cleaning Equipment see Section 3.8 and 3.9.

Consider grouping of the emissions from the M14 Furnace into three sections:

1. Primary Emissions.

These emissions are from the Primary Off-Gas Cleaning Plant.

2. Secondary Emissions.

These emissions consist of the following:

a. The fugitive emissions from furnace operation. Most of the emissions are collected by fume hoods and cleaned by the Secondary Off Gas Cleaning Plant.

b. The Secondary Off-gas Cleaning Plant. This gives the main point source emission from the stack of extracted fume cleaned by the bag house.

3. Tertiary emissions

These emissions are generated throughout the factory as a result of the M14 operation. They include:

a. Slag processing at the stockpile. b. Transport of raw materials and products on the factory roads. c. Raw material movements to the M14 Furnace organized by MMD. d. Product movements from the M14 Furnace organized by MMD.

1. Primary emissions - Primary Off-Gas Cleaning Plant

The flows of gas through the Primary Off-Gas Cleaning Plant will be very similar to M12. However it is expected in that the new gas plant


will have a greater availability. The current availability of M12 gas plant is less than 97%; the M14 gas plant will be greater than 99%.

Pressure relief

A multi-stage pressure relief system will be employed which will provide greater safety and more stable Primary Off-gas Cleaning Plant operation. See Section 3.10.

The pressure relief system is not expected to release a fugitive emission in during normal operation.

2. Secondary emissions

a. Fugitive fume emissions.

Fugitive fume emissions from the tapping, running, pouring and casting of molten alloy.

The fume collection system consists of several aspects which have undergone improvement from the M12 design to capture these fugitive fume emissions:

i. Fume extraction hoods

These are more efficient resulting in the greater capture of fume from the tapping operation.

It is expected that the fume capture efficiency of the tapping operation will be greater than 95%. This will be confirmed after the detail design stage.

ii. Smoke-Hood.

Fume captured by the smoke-hood is now conveyed to the Secondary Gas Cleaning Plant bag-house.

It is expected that the fume capture efficiency of the smoke-hood will be 90-95%. This will be confirmed after the detail design stage.

iii. Casting Bay Hoods.

These will be new in West Plant. The fume from the alloy casting will be captured and conveyed to the Secondary Gas Cleaning Plant bag-house.

Note that for it to work effectively, fume capture from the tapping hoods will have to be shut off. This is satisfactory as tapping and casting will not occur at the same time.

It is expected that the fume capture efficiency of the Casting Bay Hoods will be greater than 60-90%.


The vendor cannot be more precise than this because they have to take into account local wind conditions, access of the molten alloy ladle and access of the vehicles to remove the alloy once it has solidified.

The fume capture efficiency will be confirmed after the detail design stage when all of these factors will have been determined.

iv. Air extraction.

Approximately 26% more air will be drawn through the Secondary Gas Cleaning Plant resulting in more efficient fume extraction.

b. Secondary Off-gas Cleaning Plant Baghouse.

The emission from this bag house is guaranteed to be <30 mg/Nm3 and is expected to be significantly less than that.

For detailed specification of this emission see Appendix 24.

3. Tertiary Emissions

a. M14 results in more materials movements:

i. Proportionally (approximately) more raw materials and products are transported around the site roads.

ii. Proportionally (approximately) more raw materials and products are moved by MMD on conveyer belts.

b. Slag

M14 slag will be processed in the same manner as M12 slag.

5.5 Occupational Health, Safety and Environmental Management.

5.5.1 Quality Control Management system: Procedure No SHEQC 015

Metalloys have a procedural document for OHSAS 18001 at Metalloys.

OHSAS 18001 is essentially a guideline for the implementation of a risk based occupational health and safety management system. The development of this strategy is based on the principles of OHSAS 18001 and will be driven by line management during the normal operations and projects at Metalloys. The experience and achievements of Metalloys supports this intervention and is in line with the BHP Billiton policy for the management of occupational health, safety and the environment.

Wherever on-site labour is involved, critical task analysis and risk analysis must precede the work. Contractors will be monitored for the integrity of their health and safety planning at the pre-award process, at mobilisation and kick-off and continually through their construction activities. To support this and in recognising the opportunity for increased HSE


awareness of supervision in the construction industry, supervisory training in basic man-management and risk management principles will be given compulsorily to all contractor supervision entering the site.

The role of the contractor’s management will be defined and their progress will be measured using a systems approach. The risk based management system will be further enhanced through the participation of workers via contractors’ communications and EPCM supported initiatives including general induction, industrial theatre, safety awards and consultative forums.

Objective of SHEQC 015

To achieve excellence in the performance of health and safety during the normal operation and projects on the Metalloys site. The Target Group is all Metalloys employees and contractors.

The document SHEQC015 sets out the processes and methods that must be complied with to ensure pro-active management of Metalloys employees and contractor’s occupational health and safety during normal operation and projects at Metalloys.

All on-site contractors and service providers are required to comply with the requirements set out in this document.

Of note in the procedures are the Entry and exit medicals with a manganism test. This is compulsory for all persons who will be on site for more than 3 days.

5.5.2 BHP Billiton Occupational Health Safety Environmental Management

This is covered generally by the following regulations:

BHP Billiton 13 Management Standards. See Ref 10.21.

BHP Billiton Fatal Risk Control Standards. (BHPB FRCSs). See Ref 10.20.

Safety, Health, Environment and Quality Control Management system: Procedure No SHEQC 015. See Ref 10.3.

Metalloys Standard Operating Procedures (SOPs).

The HSEC Management Standards.

There are 13 HSEC Management Standards. The scope of these Standards covers all operational aspects and activities that have the potential to affect Health, Safety, Environment and Community’ (HSEC) either positively or negatively. They focus four areas of concern:

a. Health – promoting and improving the health of the Company’s workforce and host communities.


b. Safety – ensuring safety values are not compromised, and providing a workplace where people are able to work without being injured.

c. Environment – promoting the efficient use of resources, reducing and preventing pollution and enhancing biodiversity protection.

d. Community.

• Workforce. • External community. • Human rights.

The HSEC Management Standards cover the following:

1 Leadership and accountability. 2 Legal and other requirements. 3 HSEC hazards and risk. 4 Planning, goals and targets. 5 Awareness, competence and behaviour. 6 Communication and consultation. 7 Design, construction and commissioning. 8 Operations and maintenance. 9 Documents and records. 10 Suppliers, contractors and partners. 11 Incidents and emergencies. 12 Management of change. 13 Monitoring, audit and review.

BHP Billiton Fatal Risk Controls (FRC)

BHP Billiton have identified a series of key fatal risks to their employees – risks that require the development of sound practices to eliminate fatalities and incidents that could, in slightly different circumstances, cause fatalities. These Fatal Risk Controls(FRC), developed through workgroups made up of individuals from across BHP Billiton with extensive experience in operations, establish minimum performance expectations for managing these risk areas at leading practice levels.

These FRCs have been developed in conjunction with the BHP Billiton Charter, HSEC Policy and HSEC Management Standards and Standard Operating Procedures. See below.

These FRCs apply at all BHP Billiton controlled sites and controlled activities, and to all BHP Billiton employees, contractors and visitors when involved in controlled activities. They cover:

Fatal Risk Controls (FRC) 19th Oct 2010

1. Vehicles and mobile equipment.


2. Explosives and blasting. 3. Ground control. 4. Hazardous materials. 6. Work at height. 7. Lifting operations.

Standard Operating Procedures.

Standard operating procedures cover all the operations carried out on the sinter plant. The following are examples of some of the procedures that are for safety and health and environmental operations.

For a complete list see Ref 10.5

• Waste management. • Employee appointments. • Assembly points. • FRCSs detailed procedures. • Entry/lockout. • Induction training. • Personal protective equipment (PPE). • Register and checklist for maintenance activities. • Risk assessment. • Safety training-toolbox talks. • Site safety planning.

BHP Billiton Fatal Risk Controls (FRC) at M14.

See Ref 10.20 BHP Billiton Fatal Risk Controls.

The M14 project is conforming closely to BHP Billiton FRCsThere are some problems because the project is making the copy of a thirty year old furnace. Maintenance and ergonomics are associated with that design, and although some improvements are being made, there will still be activities associated with the original maintenance and ergonomics; they may not comply with the FRCs. It’s likely that Molten Alloy Management does comply with the FRCs.

A detailed assessment has been completed and M14 will largely comply with FRCS’s but areas requiring action have been identified and the specifics as to non-compliance areas will be identified and then designed out or mitigation measures implemented.

General ergonomics of electrode maintenance shall be improved, as well as tap-hole management due to increase floor space which will add to compliance to FRCs.

5.6 Emergency Facilities

The emergency facilities included in the furnace area:


• Fire extinguishers – for process and electrical. • Fire hoses. • Transformer fire protection. • Bunding for transformer oil. • First aid equipment including burn shields at Control room.

5.7 Risk to the public

M14 will present no further risk to “A reasonable man”, as defined by the OHS Act MHI, regulations “standing at the factory fence” of the Metalloys works.

6 ASSESSMENT OF ALTERNATIVES

6.1 Alternatives to the SAF Process

The SAF is the proven process for the reduction of manganese ores to metal.

The project is an expansion of an existing process and it is to copy the existing M12 Furnace that gives little scope for the alternatives.

Manufacture of Manganese Alloys by the Blast Furnace Process

High carbon FeMn can be produced by the carbo-thermic reduction of lumpy or sintered manganese ore in a blast furnace similar to that used for the production of pig iron in the iron and steel industry.

Disadvantages of the Blast Furnace Process for Mn alloy production:

1. High consumption of coke. 2. High manganese losses in the slag compared to SAF. 3. Lower CapEx for SAF. 4. SAF has higher yield. 5. SAF is more and flexible, when it comes to change of product; FeMn to

SiMn and vice versa.

This process has been used in the past by Amcor at the factory they once owned in Newcastle KwaZulu Natal.

6.2 Alternative Sites

West plant is the only site with sufficient space for the expansion of a furnace of the nature and size of M14. Partial infrastructure is available since the late 1970’s i.e. Foundation, Shell and surrounding building and floor outer structure, as well as decommissioned secondary off-gas plant and potential water treatment/coolers. It is a natural choice to capitalize on existing infrastructure, and to tie into the existing off-gas line to the site based Elgen plant.

6.3 Other Alternatives

Alternatives to the unit operations are feasible, and they have been considered in Best Available Technology (BAT). See Section 4.


Unit operations

The primary Gas treatment system, a scrubbing plant, will be evaluated and new technology implemented where appropriate. The intention is to improve the efficiency of the primary Gas treatment system.

Do Nothing Alternative

The Do Nothing alternative would mean that Metalloys will lose market share for manganese alloy product; it will not be able to maintain the other furnaces because of lack of capacity; and, it will not be able to meet its contractual obligations.

7 DISCUSSION AND CONCLUSIONS

The main areas of concern are fugitive emissions from tapping, running, pouring and casting, of slag and metal. Efforts will be made to reduce emissions from these operations to an acceptable level. This will be achieved by careful design of the extraction hoods to ensure optimum extraction efficiency. See Section 5.4.3 emissions. However as evident from Section 3.7.1, volume comparisons of the proposed extraction systems volumes are increased from M12 and should equate to better efficiencies and hence less emissions.

7.1 Expansion

Metalloys beneficiate manganese ores and manufacture FeMn and SiMn alloys. This is carried out by means of the submerged arc furnace (SAF) process.

Metalloys have examined the market for manganese alloys and found that there is scope to expand their operation at Meyerton. They wish to add another furnace (M14), to manufacture Mn alloys at West Plant.

Metalloys started the construction of M12 and M14 several years ago, to manufacture Mn alloys. M12 was completed and commissioned and then operated, manufacturing FeMn alloy until the present. M14 was only partially completed. This project is to complete the construction of M14, and to commission it.

7.2 The Marketing Philosophy of M12 and M14.

A portion of the HCFeMn produced by M12 and M14 is intended for the OBC Plant, to convert it into MCFeMn. The balance of the HCFeMn Product will be cast into the casting beds, crushed and sold. In practice the timing of the OBC operation will determine whether the HCFeMn feed will come from either M12 or M14, and then the balance of the alloy surplus to the OBC requirement will be cast into the casting beds.

M14 will provide a better market stance for BHP Billiton, it is being built at the time of an Eskom power shortage but when the power returns in greater quantity in 2013, M14 and other projects will be built or have been carried out and will be able to benefit from the increased power availability. Part of M14 is already built, the raw materials handling plant is largely complete, and just requires conveyer belts and other equipment for conveying raw materials to the plant. The M14 Furnace shell has been constructed but will require all of the ancillary equipment.


7.3 Design of M14

The M14 will largely be a copy of M12; but where there are known problems, notably in the areas of primary off gas handling, secondary off gas handling, new technology is being sought.

Also increased will be the amount of bag house dust and sludge produced. The bag house dust will be fed to the Pelletising Plant and recycled.

The sludge will also be fed to the Pelletising Plant but the exact mechanism for this is still being determined. M14 will also produce FeMn slag, which is intended to go to the Pre-Metrec slag stockpile.

7.4 Primary Off-Gas System

The primary off gas system will be able to handle an increased amount of gas.

Other improvements to the gas plants will be sought such as ensuring sumps are above ground level to pick up any leaks and avoid pollution of soil and ground water.

7.5 Fugitive emissions - Site

M14 will increase the impacts of the operations at the Metalloys site. In many of these cases where fugitive emissions are generated they will be increased proportionately by the increase in production due to M14.

This is most notable in the increase in the consumption of raw materials at the Metalloys site by approximately 25%. This will result in an increase in fugitive emissions of raw materials handling by a corresponding amount.

7.6 Fugitive emissions – M14

Designs are being sought which efficiently capture fugitive emissions from the various tapping, casting operations and materials handling. A study is being carried out to determine the high fugitive gas emissions points from M12 so that proper capturing facilities will be installed on M14. Consideration will be made later for installing such equipment on M12.

7.7 Furnace Pressure Relief

Pressure relief will be provided in several stages; firstly there is a higher capacity primary off gas cleaning plant, mushroom pressure relief valves, and explosion panels. These will provide greater safety and easier operation.

7.8 Furnace Hood

The fugitive emissions from the furnace shell of M12 are presently captured by the furnace hood and vented to atmosphere.

On M14 the gas will be collected from the furnace hood and routed to the secondary pollution plant thus capturing those releases.


7.9 Secondary Off-Gas System

The captured fugitive emissions will be fed to a bag-house to be cleaned of particulate matter before release to atmosphere. The existing M17 bag house will be used as a new secondary off gas system. When the emission data is available for all of the fugitive gas emissions and point source emissions, it will be given to dispersion study specialists, to determine the ground level concentration of the particulate matter.

7.10 Furnace Cooling

Closed circuit cooling water systems will be used for both shell cooling and equipment cooling with fin fan coolers thereby producing water economy.

7.11 Power.

M14 will also increase the power usage at the Metalloys site by approximately 25%.

7.12 Best Available Technology

In general best available technology has been sought and incorporated into the design of M14. In particular the Best Available Technology available from the Integrated Pollution Prevention and Control (IPPC) is being evaluated and incorporated where appropriate.

7.13 HSEC Issues

The M14 Furnace operation has hazards of heat, noise and dust. However it is an operation which Metalloys is familiar with and has standard operating procedures for ensuring the protection of all personnel. This includes appropriate personnel protective equipment (PPE) and instructions and management of their use.

There are no new substances involved in the process which Metalloys is not familiar with.

With the take-over by BHP Billiton the high standards of that company are being introduced. Of note are the HSEC Management Standards, and the 7 Fatal Risk Controls (FRC) these in combination with Metalloys Standard Operating Procedures are producing a high quality safety, health and environmental management system.

7.13.1 Dust

Baseline dust sampling was conducted to measure fugitives at West Plant:

• The highest dust concentration of 58mg/m3 occurred at Raw materials vibrator feeder between 12:50pm and 9:01pm on 14 January 2009.

• In general, based on 8 hour averages, the concentration of dust at all the sites were below 1mg/m3 except at Raw Material Belt Feeder on 19 January and Fourth Floor, each recording 1mg/m3 and 3mg/m3 respectively.

See Ref 10.25. Fugitive measurements at West Plant Report No AS0488 02 March 2009 ECOSERV (Pty) Ltd.


7.13.2 Manganism

Manganism is a serious disease caused by inhaling dust-containing manganese. Fugitive emissions from all of these stages outlined above can give rise to manganism if inhaled. Dust masks are required in the furnace area, but a much better principle is to engineer out these emissions as outlined above so they do not occur.

7.13.3 Noise

Most of the West Plant Operations have acceptable noise levels. The possible exceptions are the fans on the M17 bag-house which is planned to be used as a secondary pollution plant. These fans have a noise level which require it to be demarcated as a noise area requiring ear plugs or ear muffs. It is not an area of high work intensity.

7.14 Alternatives

The submerged arc furnace is well established for the manufacture of Manganese Alloys. It is possible to use the blast furnace technology but it is not economic, it is very inflexible and cannot manufacture SiMn. Any operation that would require change in through put, or change in grade would be slow and difficult with the blast furnace.

The M14 Furnace is ideally situated in West Plant mainly because it is partly constructed at West Plant, and all of the required furnace infrastructure is established there.

7.15 Missing Information

This study still requires more information, which will be sought for the report to be complete. The missing information in the form of questions is in the context where it is applicable inside this report. It is summarized in Section 9.

8 RECOMMENDATIONS

The report has highlighted all SHE issues associated with the M14 project and the mitigations for them.

The project should proceed with the EIA.

9 OUTSTANDING INFORMATION

There is no outstanding information required for the completion of this report.

10 REFERENCES

1. Contractor Management – Complete Version SHEQC 015. July 2001. 2. FRCS 5 – Hazardous Materials Management. Metalloys SHEQC 017 SP 15 Nov

2005 3. SHEQC – Risk Management. Metalloys SHEQC 001 SP 4 Jan 2006. 4. Waste Management. SHEQC 016 SP. 20 May 2005 5. CD ROM: Metalloys Contractor Management System (CMS). March 2005.


6. Occupational Hygiene Risk Assessment. Samancor Meyerton Silicon Manganese Furnace & Molten Slag Furnace Revision. Ref: Sma/Pp/05/00-05. December 2005. (M16/M17)

7. Air Quality Impact Assessment for the Metal Recovery and Slag Processing Plant at the Samancor Meyerton Works. Report No.: App/06/Alp-01 Rev 0 August 2006: Y Scorgie, G Kornelius, N Krause.

8. Best Available Techniques Reference Document on the Production of Iron and Steel. European Commission: Integrated Pollution Prevention and Control. Dec 2001.

9. Transport activities at Samancor. 10. Samancor Metalloys Risk Matrix R & S Cronje 12 July 2000 11. US EPA AP42 Section 12.5. 12. US EPA Report EPA -450/4-84-007h. 13. Air Quality Impact Assessment for the Proposed Metal Recovery and Slag

Processing Plant at the Samancor Meyerton Works. Report No.: App/07/Alp-01 Rev 0 2007.

14. Air Quality Impact Assessment and Development of an Air Quality Management Plan for the Metalloys Plant Meyerton. Report No MTX/02/MET-01b.

15. Waste stream planning 2006 ex PvSch.xls. 16. Best Available Techniques Reference Document on Non-Ferrous Metals Industries.

European Commission: Integrated Pollution Prevention and Control. 17. MikroPul (Pty) Ltd. Evapark Block B, Cresta Johannesburg South Africa

www.mikropul.com . 18. A Review of Dioxin emissions and Cement Kilns. Gossman Consulting Inc Sept

1994. 19. K’enyuka Process Design Basis and Mass Balance for M14 Furnace.April 2008 20. BHP Billiton Fatal Risk Controls. 21. BHP Billiton Health, Safety, Environment and Community (HSEC) Management

Standards Issue No. 3 (STA009) 20th Aug 2008. 22. M14 Furnace Project: Dust Extraction Points for M12 and M14. Ecoserv AS0488 7

Aug 2008. 23. M12 Heat stress levels: Occupational hygiene monitoring and Medical Surveillance

Programmes. Pumeza Kalipa, Occupational Hygiene & Health Co-ordinator, Metalloys, BHP Billiton.

24. Classification and evaluation of disposal and utilization options for silicon-manganese slag and ferro-manganese slag and DMS bag-filter dust - Oct 2001 Dave Baldwin ECC.

25. Fugitive measurements at West Plant Report No AS0488 02 March 2009 ECOSERV (Pty) Ltd.

26. Baseline Air Quality Impact Assessment for the Samancor Manganese Metalloys Plant in Meyerton as Part of an Emission Reduction Strategy. Report No.: APP/08/CYM - 02 Rev 0. August 2008. N Krause; G Kornelius. Airshed Planning Professionals (Pty) Ltd.

27. M14 Furnace Execution. Response to Metalloys Queries Secondary Off Gas Cleaning Plant. 05410003 – 04 - REP - 0001


11 APPENDICES

1. Hazard Study 1 - Chemical Hazards Proforma 84 RAW MATERIAL SPECIFICATION SHEETS 86 2. RM1 Mn Ore NHO 86 3. RM2 Mn Ore MMT (M1L) 88 4. RM3 Mn Sintered Ore Mamatwan High Grade Sinter (MHS) 89 5. RM4 Mn Sintered Ore - Mamatwan Standard (Middle) Grade Sinter (MMS) 90 6. RM5 Iron Ore 91 7. RM6 Mn Ore GEMCO 92 8. RM7 Quartz (Silica) 93 9. RM8 Chinese Coke. 94 10. RM9 FeMn Briquettes . 95 11. RM10 Forzando Coal 96 12. RM10a Sprague Coal 97 13. RM11 Electrode Paste 98 14. RM13 Power 99 PRODUCT SPECIFICATION SHEETS 100 15. P1 High Carbon Ferro- Manganese (HCFeMn) Product for Sales 100 16. P2 High Carbon Ferro- Manganese (HCFeMn) to OBC 103 17. P3 Bag Filter Dust to Pelletising Plant 104 18. P4: Furnace Clean Off-gas to Elgen Plant 106 19. P5 Scrubber Water Sludge Separated at Pelletising Plant 107 20. P6 FeMn alloy Slag 109 GASEOUS WASTE SPECIFICATION SHEETS 110 21. Summary of findings from APPA Study for M12 110 22. WG1 M14 Raw Materials Handling Emission 111 23. WG2, WG8 and WG9 :M14 Molten Alloy Emissions including WG1 112 24. PSE3 M14 Secondary Pollution Plant Baghouse Point SourceEmission 113 25. WG4 M14 Bag-Filter Dust at Stockpile - Fugitive Emissions 114 26. WG5 M14 Molten Slag Emergency Casting Emissions 115 27. WG6 M14 Molten FeMn Slag casting at Stockpile - Emissions 116 28. WG7 M14 Molten Slag Pouring into Slag Carrier Ladle Fugitive Emissions 117 29. WS3 Bag Filter Dust to Stockpile 118 30. WS4 Slag to Stockpile 119 31. WL1 Cooling Water losses and Sewerage 120 STOCKPILE SPECIFICATION SHEETS 121 32. SP1 Cast Ferro-Manganese 121 33. SP3 Cast Slag at Stockpile 122 34. SP4 Bag House Dust at Stockpile 123 OTHER ITEMS 124 35. Emergency response procedure. 124 36. Further Studies That are being Considered by the M14 Project 125 37. M14 Project Organogram 126 38. Dioxins and Furans 127 39. Stack Height Relative to Any Nearby Building 130 40. M14 Raw Materials Handling – Dust removal points 131


1. Hazard Study 1 - Chemical Hazards Proforma

PROJECT : M14 Furnace PLANT : West Plant Metalloys

HAZARD 'Blank' INSIGNIFICANT HAZARD

POTENTIAL 'K' HAZARDS KNOWN AND UNDERSTOOD

KEY 'Sequential Number' SEE NUMBERED NOTES

CHEMICAL (or group of chemicals)

PHYSICAL STATE

QUANTITY EXPLOSION AND FLAMMABILITY

REACTIVE STABLITY HAZARDS

IMMEDIATE HEALTH

HAZARDS

CHRONICHEALTH HAZARDS

OTHER HEALTH

HAZARDS

ENVIRONMENTAL HAZARDS

HAZARD-BREAK-DOWN

PROBLEMS IN

(inventory / throughput)

MSDS? Y/N

Fire DeflagrateDetonate

Electrical Static

Inhala-tion

Corro-sive

Sens-itizer

Other Odour Radia-tion

Water Air Ground PROD-UCTS

HANDLING

PRODUCTS

SiMn alloy alloy S t/d -- Y K1 - - - K K5 - K K- - - - K2 - -

SiMn Slag # S t/d -- Y - - - - - - - - - - - - - -

FeMn Alloy Alloy S t/d -- Y K1 K K5 K K K2

Furnace dust # S t/d -- Y - - - - - - - - - - - - - - -

FeMn Slag # S t/d -- Y K5 K K2

RAW MATERIALS

W1L S t/d -- Y K1 - - K K K5 - - K - - - K2 - -

MMT S t/d -- Y K1 - - K K K5 - - K - - - K2 - -

quartz S t/d -- Y - - - - K - - - K - - - K2 - -

Forzando Coal # S t/d -- Y - - - - - - - - - - - - - - -

Chinese Coke # t/d -- Y - - - - - - - - - - - - - - -

SiMn Slag See Slag above - - - - - - - - - - - - - -

SiMn Briquettes See SiMn above - - - - - - - - - - - - - -

SKROT See Slag above - - - - - - - - - - - - - -

Pellets See furnace dust above - - - - - - - - - - - - - -

MMS S t/d -- Y K1 - - K K K - K K - - - K2 - -

Sprague Coal S t/d -- Y K K


PROJECT : M14 Furnace PLANT : West Plant Metalloys

HAZARD 'Blank' INSIGNIFICANT HAZARD

POTENTIAL 'K' HAZARDS KNOWN AND UNDERSTOOD

KEY 'Sequential Number' SEE NUMBERED NOTES

CHEMICAL (or group of chemicals)

PHYSICAL STATE

QUANTITY EXPLOSION AND FLAMMABILITY

REACTIVE STABLITY HAZARDS

IMMEDIATE HEALTH

HAZARDS

CHRONICHEALTH HAZARDS

OTHER HEALTH

HAZARDS

ENVIRONMENTAL HAZARDS

HAZARD-BREAK-DOWN

PROBLEMS IN

(inventory / throughput)

MSDS? Y/N

Fire DeflagrateDetonate

Electrical Static

Inhala-tion

Corro-sive

Sens-itizer

Other Odour Radia-tion

Water Air Ground PROD-UCTS

HANDLING

- - - - - - - - - - - - - - -

S t/d -- Y K K

BHP Coke S t/d -- Y K K

Coke and fines S t/d -- Y K K

AUXILIARY CHEMICALS

Electrode Paste S t/d -- Y K8 - - - K8 - - - K8 - - - - - -

Carbon Dioxide G t/d -- Y - - - - K - - - - - - - K - -

Cornwall Coal S t/d -- Y K K- - - K9 - - - - - - - K - -

Oxygen G t/d -- Y K10 K10 - - - - - - - - - - - -

Refractory cast S/L t/d -- Y - - - - K - - - - - - - - - -

Refractory Gun S/L t/d -- Y - - - - K - - - - - - - - - -

Taphole clay S/L t/d -- Y - - - - K - - - - - - - - - -

Vermiculite S t/d -- Y - - - - K - - - - - - - - - -

RM Dust suppressant #1

L t/d -- Y - - - - - K - - - - - - - - -

RM Dust suppressant #2

t/d -- Y - - - - - K - - - - - - - - -

- - - - - - - - - - - - - - -

PROFORMA HS1A AECI ENGINEERING

# Require MSDS for this material

Notes : .

K1. Can form of hydrogen gas in contact with water. K2. Dust a generated by material handling, crushing etc. K5. Dust is an irritant

K8. Paste vapour emitted when heated, which is toxic, carcinogenic, and flammable K9. Toxic gas K10 Oxygen supports combustion and explosion. .


M14 PROJECT

RAW MATERIAL SPECIFICATION SHEETS

2. RM1 Mn Ore NHO

PLANT/SYSTEM NAME: Page

STREAM NAME: Reference RM 1

ANNUAL RATE - Case; Product: HCFeMn 17.05t/h Date 31 May 2008

CONDITIONS DEFINED AT Site, ambient Revision 0

REFERENCE SOURCE: Metalloys Mass Balance 20 April 2009

AVAILABILITY 98% AMOUNT STORED 150t

UNIT DESIGN MAXIMUM MINIMUM

FLOWRATE kg/h 6420

FLOWRATE inc Availability t/a 55 086

PRESSURE kPa(g) Amb

TEMPERATURE oC Amb

COMPOSITION - % w/w IMPURITIES: ppm

CaO 6.2 For Heavy metals and Trace Elements

MgO 0.6 See next page

BaO 0.1

Al2O3 0.1

SiO2 4.7 Mn/Fe – 5.2

Mn 48.9 Mn + Fe – 58.3

Fe 9.4

Screen size

Particle Size Distribution including Dust <200Mesh (75µm)

Bulk Density - 2.23t/m3

INTENDED MEANS OF HANDLING:

Material arrives on site by rail or road truck and stored in a bulk storage bunker at the Metalloys MMD. It is sprayed with a dust suppressant chemical. A conveyor belt takes it to the West Plant where it is stored in a storage bunker. The dust suppressant chemical is effective until the material reaches the day bin prior to charging the furnace.

POTENTIAL EFFECTS:

Dust emissions into the atmosphere impacting the site and local area, employees and local community.

Notes: The figures may differ from the heavy metals and trace elements analysis overleaf; it is the normal spread found in routine sampling


Complete analysis of Manganese ores. Ref Metalloys labs

ELEMENT Unit M1L/MMT NHO MHS MSS Mn %w/w 38.5 45.7 49.0 54.4

Fe %w/w 4.4 11.0 4.92 5.80

SiO2 %w/w 4.4 3.83 6.08 6.70

CaO %w/w 14.3 8.1 14.4 16.0

Al2O3 %w/w 0.25 0.29 0.57 0.63

MgO %w/w 3.11 1.11 3.60 3.90

AgO ppm w/w <5 <5 <5 <5

As2O3 ppm w/w 31 20 <10 19

B2O3 ppm w/w 1588 1497 2591 2405

BaO ppm w/w 351 2018 518 560

BeO2 ppm w/w <5 4 <5 <5

Bi2O3 ppm w/w <5 <5 <5 <5

CdO ppm w/w <1 <5 <5 <5

Co3O4 ppm w/w 70 115 85 69

Cr2O3 (Crvi) ppm w/w 41 40 56 34

CuO ppm w/w 35 128 16 22

Ga2O3 ppm w/w <10 46 29 30

I2 ppm w/w 49 61 86 53

K2O ppm w/w 274 170 273 733

MoO3 ppm w/w <5 <5 <5 <5

N2 ppm w/w 437 197 151 99

Na2O ppm w/w 670 371 626 1354

NiO ppm w/w 38 41 21 27

P2O5 ppm w/w 630 1271 1338 1397

PbO ppm w/w 28 102 71 7

SO3 ppm w/w 2475 3530 500 1009

Sb2O3 ppm w/w <5 <5 <1 <5

Sc2O3 ppm w/w <5 <5 <5 <5

SeO2 ppm w/w <5 <5 <5 <5

SnO2 ppm w/w <5 <5 <10 <5

SrO ppm w/w 193 <5 178 232

Ta2O% ppm w/w 129 158 165 144

TeO2 ppm w/w <5 <5 <5 <5

TiO2 ppm w/w 57 197 318 347

Tl2O3 ppm w/w <5 <5 <5 <5

V2O5 ppm w/w <10 <5 <5 <5

ZnO ppm w/w 70 186 92 78

ZrO2 ppm w/w <5 16 16

C ppm w/w 4.53 1.13 0.14 0.15


M14 PROJECT

RAW MATERIAL SPECIFICATION SHEET

3. RM2 Mn Ore MMT (M1L)

PLANT NAME: Raw Materials Handling Page

STREAM NAME: Manganese Ore W1 Reference RM 2


CONDITIONS DEFINED AT: Site, Ambient Revision 0




FLOWRATE t/h 3.21


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb

COMPOSITION % w/w IMPURITIES: ppm

Mn 37 min See previous page

Fe 4 - 5

CaO 14 - 17

SiO2 4 – 4.5

MgO 4.0 max

Mn/Fe 7.4min

Particle Size Distribution including Dust 20mm x 75mm

Dust To be provided by the Metalloys APPA Study.

<200Mesh (75µm) To be provided by the Metalloys APPA Study.




POTENTIAL EFFECTS:


Notes:


M14 PROJECT


4. RM3 Mn Sintered Ore Mamatwan High Grade Sinter (MHS)


STREAM NAME: Manganese Ore MHS Reference RM 3






FLOWRATE t/h 0

FLOWRATE inc Availability t/a 0

PRESSURE kPa(g) Amb

TEMPERATURE oC Amb


Mn 48.5 See previous page

Fe 5

CaO 14 - 17

SiO2 6.5

MgO 4.0 max

BaO 0.1 Mn/Fe – 9.7min

Al2O3 0.1 Mn + Fe – 53.5






POTENTIAL EFFECTS:


Notes:


M14 PROJECT


5. RM4 Mn Sintered Ore - Mamatwan Standard (Middle) Grade Sinter (MMS)


STREAM NAME: Manganese Ore MMS Reference RM 4






FLOWRATE t/h 22.46


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb


Mn 45.9 min See previous page

Fe 5.2

CaO 14 - 17

SiO2 6.2

MgO 4.0 max

BaO 0.1 Mn/Fe – 8.8

Al2O3 0.1 Mn + Fe – 51.1







POTENTIAL EFFECTS:


Notes:


M14 PROJECT


6. RM5 Iron Ore


STREAM NAME: Iron Ore Reference RM 5






FLOWRATE t/h 0


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb


MnO2 0.3

Fe2O3 85.7

CaO

SiO2 2.4

MgO

BaO

Al2O3 11.6


PM To be provided if necessary




POTENTIAL EFFECTS:


Notes:


M14 PROJECT


7. RM6 Mn Ore GEMCO


STREAM NAME: Manganese Ore GEMCO Reference RM 6






FLOWRATE t/h 0


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb


Mn 44.8 Will be obtained if required.

Fe 3.1

CaO 0.1

SiO2 15.9

MgO 0.1

Mn/Fe 14.5 Mn+Fe 47.9

Al2O3 5.2







POTENTIAL EFFECTS:


Notes:


M14 PROJECT


8. RM7 Quartz (Silica)


STREAM NAME: Quartz (Silica) Reference RM 7

ANNUAL RATE - Case; Product: HCFeMn 17.05 t/h Date 31 May 2008





FLOWRATE t/a 1.66


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb


SiO2 98 To be obtained if required

Fe2O3 0.5

Al2O3 0.5

Mn 0.2

P 0.001


<200Mesh (75µm)




POTENTIAL EFFECTS:

Dust emissions into the atmosphere impacting the site and local area, employees and local community. Could cause silicosis.

Notes:


M14 PROJECT


9. RM8 Chinese Coke.


STREAM NAME: Chinese Coke Reference RM 8

ANNUAL RATE: Case; Product: HCFeMn 17.05t/h Date 31 May 2008





FLOWRATE t/h 2.86


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb


Fixed Carbon 85 This is a typical coke of many kinds used. If necessary obtain the spec of the actual coke used.

Volatiles 1

Ash 13

Moisture 5

P 0.04


To be provided by the Metalloys APPA Study.





POTENTIAL EFFECTS:


Notes:


M14 PROJECT


10. RM9 FeMn Briquettes .


STREAM NAME: FeMn Briquettes Reference RM 9



REFERENCE SOURCE: Metalloys Mass Balance 20 April 2009, FeMn product Analysis



FLOWRATE t/h 0


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb


Mn 78 As per FeMn alloy P1

Fe 12

Si 0.5

C 7.5

P 0.05

S 0.01 Mn/Fe – 6.5

Al 0.01 Mn + Fe - 90

Particle Size Distribution including Dust

To be provided by the Metalloys APPA Study.




Undersized Mn alloy product that is unsuitable for sale is briquetted and conveyed by road truck and stored in a bulk storage bunker at the Metalloys MMD. A conveyor belt takes it to the West Plant where it is stored in a bunker.

POTENTIAL EFFECTS:


Notes:


M14 PROJECT


11. RM10 Forzando Coal


STREAM NAME: Forzando Coal Reference RM 10



REFERENCE SOURCE: Metalloys Mass Balance 20 April 2009; MMD Spec sheet



FLOWRATE t/h 5.61


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb

CAPACITY t


Fixed Carbon 54 This is a typical coal of many kinds used. If necessary obtain the spec of the actual coal used.

Volatiles 30

Ash 15

Moisture 5

P 0.04





POTENTIAL EFFECTS:


Notes:


M14 PROJECT


12. RM10a Sprague Coal


STREAM NAME: Sprague Coal Reference RM 10a

ANNUAL RATE: Case; Product: HCFeMn 17.05t/h Date 6 Nov 2008


REFERENCE SOURCESprague Coal MSDS



FLOWRATE t/h 0


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb

CAPACITY t


Fixed Carbon 50 - 72 This is a typical coal of many kinds used. If necessary obtain the spec of the actual coal used.

Volatiles 17 - 37

Ash 4 - 20

Moisture 1 - 10

P 0.04





POTENTIAL EFFECTS:


Notes:


M14 PROJECT


13. RM11 Electrode Paste


STREAM NAME: Electrode Paste Reference RM 11



REFERENCE SOURCE:; Summary consumptions for April, 2007 MMD01:cd:Rev02



FLOWRATE t/h 0.21


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb

CAPACITY t


Calcined Anthracite 75 To be obtained if necessary

Coal tar pitch 25


Electrode paste is manufactured by vendor and imported by road truck to West Plant where it is stored. It is fed to the Soderburg Electrode system to manufacture the electrode in situ.

POTENTIAL EFFECTS:

Fume from the Electrode mantle. Likely to contain coal-tar volatiles, PAHs. A hazard to operators.

Notes:


M14 PROJECT


14. RM13 Power


STREAM NAME: Power Reference RM 13

ANNUAL RATE: 90 140 MWh/a Date 1 June 2008

CONDITIONS DEFINED AT Revision 0

REFERENCE SOURCE:; Summary consumptions for April, 2007 MMD01:cd:Rev02

LINE NUMBER


Furnace Rating MVA 81

PRESSURE kPa(g) N/A

TEMPERATURE oC N/A

CAPACITY MWh/t 2.555 – per t of hot metal

Power MVA 81 81 61 - 65

Power MW 48 481 44 - 48

PROPERTIES COMMENTS

V 11kV & 33kV

Transformed to 120kA and 109 V

Power factor 75% Primary Control is resistance by adjustment to the electrodes. Secondary control is of the Current by changing the transformer tap settings.

Furnace rating 48MW

Electrode voltage 109v

Energy Consumption per t of hot metal.

2.555 MWh/t

Other Propertes


POTENTIAL EFFECTS:

Notes:


M14 PROJECT

PRODUCT SPECIFICATION SHEETS

15. P1 High Carbon Ferro- Manganese (HCFeMn) Product for Sales

PLANT NAME: M14 Furnace Page

STREAM NAME: Ferro-Manganese Product (HCFeMn) Reference P1

ANNUAL RATE: Case; Product: HCFeMn 17.05t/h Date 1 June 2008



AVAILABILITY 98% AMOUNT STORED See Stock-Pile Sheet SP1


FLOWRATE t/h 17.05


PRESSURE kPa(g) Amb

TEMPERATURE oC Amb

CAPACITY t

COMPOSITION % w/w IMPURITIES: %w/w

Mn 78 Si 0.5

Fe 15.5 P 0.01

C 7.5 C 7.5

S 0.03

Al 0.05

See next Page


To be provided by the Metalloys APPA Study

<200Mesh (75µm ) To be provided by the Metalloys APPA Study


Mn alloy is tapped from the furnace into a ladle from its own tap-hole. After weighing it is cast into an open area and allowed to solidify. It naturally cracks as it cools. 13 – 15 castings are made each day and after 2 – 3 days several layers have been cast. At that point a front-end-loader breaks up the layers and loads them on to a truck. The truck conveys the product to Materials Management Department for crushing and screening into the various product size ranges.

POTENTIAL EFFECTS:

Dust and fume from the tapping operation, running off the molten alloy in the launder, pouring into the ladle , casting from the ladle into the Casting bed. These dust and fume emissions into the atmosphere impact upon the site and local area, employees and local community.

Notes:


FeMn Product – Analysis of Minor and Trace elements (Ref Samancor Lab Report TS 436 CD Rev 0

Metalloys

(A Division of Samancor Ltd)

Registration No:1926/008883/06

PRODUCT:- FeMn Alloy (TYPICAL Jan-Dec2007) Specification- Metalloys Product Register

Code %Mn %Fe %Si %Al %S %P %C FeMn 10x50mm min max max max max max max

78.0 15.5 0.50 0.05 0.03 0.10 7.5 Indicative Chemical Properties Minor & Trace Elements

Major Elements Elements in ppm Mean

Element Mean

Range As 12 B 242

% Mn 78.5 78.0 78.8 Bi 36 % Fe 14.1 13.8 14.8 Ba 25 % Si 0.03 0.02 0.40 Be <5% Al 0.007 0.006 0.010 Co 124 % P 0.066 0.050 0.080 Cr 427 % S 0.010 0.013 0.025 Cu 92

% Mg 0.007 0.005 0.040 Cd 15 % Ca 0.041 0.025 0.080 K 82 % C 7.00 6.85 7.50 Mo 95

N2 219 Na 949

Screen Ni 91 - Fraction + Fraction Pb 160 Sb <5 Se <5 Sn 159 Te <5 Ti 65

TS 436 CD Rev 0: 10/2005 V 97

Zn 27


SiMn Product – Analysis of Minor and Trace elements (Ref Samancor Lab Report TS 436 CD Rev 0

Metalloys(A Division of Samancor Ltd)Registration No:1926/008883/06Address:P.O.Box 66Meyerton, 1960South Africa Tel: (016) 360 2111Fax: (016) 360 2506

Our Ref:Your Ref

PRODUCT:- SiMn Alloy (TYPICAL Jan-Dec 2006)Specification- Metalloys Product Register

Code %Mn %Fe %Si %Al %S %P %C FeMn 10x50mm min max min max max max max

65.0 15.0 16.0 0.05 0.03 0.10 1.80

Indicative Chemical PropertiesMinor & Trace Elements

Major Elements Elements in ppm MeanElement Mean Range As 50

% Mn 66.5 66.0 66.8 B 227% Fe 14.0 13.9 14.4 Bi 86% Si 16.8 16.6 17.5 Ba <10% Al 0.010 0.008 0.02 Be <5% P 0.052 0.040 0.060 Co 164% S 0.015 0.014 0.018 Cd 25

% Mg 0.008 0.006 0.020 Cr 231% Ca 0.077 0.038 0.082 Cu 115% C 1.75 1.70 1.79 K 111

Mo 116N2 303Na 87

Screen Ni 247 - Fraction + Fraction Pb 150

Sb <5Se <5Sn 149Sr <10Ta 144Te <5Ti 823V 115

Zn 75

TS 436 CD Rev 0: 10/2005


M14 PROJECT

SPECIFICATION SHEET

16. P2 High Carbon Ferro- Manganese (HCFeMn) to OBC


STREAM NAME: Ferro-Manganese Product (HCFeMn) Reference P2




AVAILABILITY 90% AMOUNT STORED


FLOWRATE t/h Nil

FLOWRATE inc Availability t/a Nil

PRESSURE kPa(g) Amb

TEMPERATURE oC Amb

CAPACITY t


See P1



<200Mesh (75µm ) To be provided by the Metalloys APPA Study


Mn alloy is tapped from the furnace into a ladle from its own tap-hole. After weighing it is taken by the crane to the oxygen blown converter (OBC). The Mn alloy alloy is decanted into the OBC vessel. This is not the normal operation. In theory the OBC will normally be supplied by M12. In practice the OBC will be supplied by either M12 or M14 depending upon which is ready. See Section 3.6.

POTENTIAL EFFECTS:

Dust and fume from the tapping operation, running off the molten alloy in the launder, pouring into the ladle and pouring from the ladle into OBC.

Notes:


M14 PROJECT

PRODUCT SPECIFICATION SHEET

17. P3 Bag Filter Dust to Pelletising Plant


STREAM NAME: Bag Filter Dust to Pelletising Plant. Reference P3


CONDITIONS DEFINED AT: Site, ambient Revision

REFERENCE SOURCE: : Metalloys Mass Balance 20 April 2009

AVAILABILITY 90% AMOUNT STORED a few tons in the bag filter.


FLOWRATE t/h 0.01


PRESSURE Amb

TEMPERATURE oC Warm

COMPOSITION: % w/w IMPURITIES %w/w

See next page

Particle Size Distribution: PM10 To be provided by the Metalloys APPA Study. INTENDED MEANS OF DISPOSAL:

Dust will be stock piled and later pelletized.

POTENTIAL EFFECTS:

Dust emission when the dust is stockpiled on the stockpile SP4. This dust emission into the atmosphere impact upon the site and local area, employees and local community. .

Notes:


Manganese Oxide Fume

TYPICAL ELEMENT MICRONS %

Al203 0.029

C 0.16

CaO 0.59

FeO 3.13

LOI 0.17

MgO 0.55

Mn 67.4

MnO 3.3

MnO2

Mn304 95.8

Moisture 0.34

Na2O 1.37

Particle Size 6.74

S 0.0093

SiO2 0.19

ELEMENT PPB PPM

As 7.1

BaO 26

Cr2O3 79

CuO 86

Hg <10

K2O 440

NiO 80

Pb 104

SnO2 211

SrO <10

TiO2 <10

V2O5 125

ZnO 132

Bulk Density: 1.07 t/m

Typical Moisture content + - 0.35% this can vary with the conditions of the upstream process ,

it can reach + - 0.8 % but this is only with adverse conditions but it does happen from time to time ,


M14 PROJECT

GASEOUS PRODUCT SPECIFICATION SHEET

18. P4: Furnace Clean Off-gas to Elgen Plant

PLANT NAME: M14 Gas Cleaning Plant Page

STREAM NAME: Furnace Clean Off-gas to Elgen Plant. Reference P4




AVAILABILITY 90%

UNIT ACTUAL MAXIMUM MINIMUM

FLOWRATE Nm3/h 14 000

FLOWRATE t/h 10.65


PRESSURE Ambient

TEMPERATURE oC ~50

COMPOSITION: % v/v IMPURITIES: RANGE ppm UNIT

Hydrogen 14.1

Carbon monoxide 50.8

Oxygen 0.4

Carbon Dioxide 16.4

Nitrogen Nil

Water vapour Dry Basis. See water balance 14.5

INTENDED MEANS OF DISPOSAL:

Combusted in Elgen boiler generating steam and then 10MW of power.

POTENTIAL EFFECTS:

From M12 Tanabe document, confidential to BHP Billiton

Notes:


M14 PROJECT


19. P5 Scrubber Water Sludge Separated at Pelletising Plant

PLANT NAME: Pelletising Plant Page

STREAM NAME: Scrubber Water Sludge Reference P5


CONDITIONS DEFINED AT: Site, ambient Revision 0



FLOWRATE 1.2


PRESSURE Amb

TEMPERATURE oC Warm

COMPOSITION: % w/w IMPURITIES %w/w

MnO 47.9 BaO 0.082 Fe 1.19 Cr2O3 0.08 SiO2 8.06 CuO 0.001 MgO 2.9 K2O 1.18 CaO 7.3 NiO 0.001 ZnO 0.77 PbO 0.15 NaO2 3.86 SnO2 0.002 Al2O3 2.27 SrO 0.079 Tar Not Determined TiO2 0.031 V2O5 0.026

Low mobility sludge INTENDED MEANS OF DISPOSAL:

Sludge will be stock piled and later pelletized.

POTENTIAL EFFECTS:

Soil and groundwater pollution if the sludge is dumped on unsealed ground.

Notes:Information awaited for the pelletizing plant.


M14 PROJECT


20. P6 FeMn alloy Slag


STREAM NAME: FeMn Slag to Further Processing Reference P6




AVAILABILITY 90% Amount taken in Slag Ladle - 40t Normally


FLOWRATE t/d nil

FLOWRATE inc Availability t/a nil

PRESSURE kPa(g) Amb

TEMPERATURE oC 1450

CAPACITY: Slag carrier t 40t 60t 0


MnO 25% TiO2 0.15

Fe0 0.2% P2O5 <0.01

SiO2 (A) 32% Total S 0.86

CaO (B) 31% Cr2O3 0.01

MgO (C) 7% V2O5 <0.01

Al2O3 (D) 8% BaO 0.20%

Basisity (B+C)/(A+D) 0.95 K2O 0.14

Na2O 0.24

To Particle Size Distribution including Dust 20mm x 40mm

PM10 and PM2.5 To be provided by the Metalloys APPA Study

<200Mesh (75µm) To be provided by the Metalloys APPA Study


FeMn slag is tapped by its own tap-hole from the furnace into a ladle. It is then poured into a mobile slag ladle and carrier. Metalloys is looking for an alternative use for this slag other than dumping it.

POTENTIAL EFFECTS:

Fume, dust impact on the working environment, and community Notes:


M14 PROJECT

GASEOUS WASTE SPECIFICATION SHEETS

21. Summary of findings from APPA Study for M12

Source name Height of Release Above

Ground (m)

Actual Gas

Volumetric Flow (m³/h)

Concentration (mg/Nm³)

Emission of PM g/s

Emission of PM t/a

Comments

M12 clean gas stack 55 402 80 0.01 0.25 Intermittent

M12 raw gas stack A and B 52 94.8 406 0.33 Intermittent

M12 raw material stacks

x4 50 Intermittent

Secondary pollution stack 30 90 693 15 Intermittent


M14 PROJECT

GASEOUS WASTE SPECIFICATION SHEET

22. WG1 M14 Raw Materials Handling Emission

PLANT NAME: M14 RMH Emission Page

STREAM NAME: Raw Materials Handling Emission Reference WG8


CONDITIONS DEFINED Site, ambient Revision 0


AVAILABILITY 90% AMOUNT STORED 21t – ½ h buffer capacity

UNIT ACTUAL MAXIMUM MINIMUM

FLOWRATE t/h Included in

FLOWRATE inc Availability t/a Other alloy fugitive emissions from Furnace operation

PRESSURE Ambient

TEMPERATURE oC Ambient

COMPOSITION: % v/v IMPURITIES: RANGE ppm UNIT

Air Dust mg/Nm3

Raw material dust Treated with dust suppressant

Dust Burden mg/sec

Dust Composition %w/w



Discharged to atmosphere

POTENTIAL EFFECTS:

Ground level concentrations of dust in the local community.

Notes:


M14 PROJECT


23. WG2, WG8 and WG9 :M14 Molten Alloy Emissions including WG1

PLANT NAME: M14 Furnace Area Page

STREAM NAME: Molten Alloy Emissions: Tapping, casting, and supplying OBC.

Reference WG8




Height Ground level

AVAILABILITY 90% Proportion of Alloy going to OBC %:

FUME AND DUST UNIT DESIGN To Casting Beds

To OBC Normally

FLOWRATE t/h 0.0051 0.0051 Nil

FLOWRATE inc Availability t/a 43.50 43.50 Nil

PRESSURE Ambient Ambient

TEMPERATURE oC 1350 1350

Activity Emission Factor

kg/t Efficiency of Collection

% Fugitive Emission

kg/a

Tapping (Taphole, runner, & into ladle.)

# # #

Casting into bed # # #

Pouring into OBC (Normally nil)

# # #

#To be provided by the Airshed study

For heavy metal and trace element analysis. See baghouse dust P3.


Portion of emission collected by secondary pollution hoods

Balance forms a fugitive emission which is discharged to atmosphere

POTENTIAL EFFECTS:


Notes:


M14 PROJECT


24. PSE3 M14 Secondary Pollution Plant Baghouse Point SourceEmission

PLANT NAME: M14 Secondary Pollution Plant Baghouse Page 1

STREAM NAME: Emission Reference PSE3

ANNUAL RATE: Case; Product: HCFeMn 17.05t/h Date 28.12.2010


REFERENCE SOURCE: :M12 DCS,BATEMAN SPEC SHEETS,FLOW,PRESSURE,VOLUME, VELOCITY READINGS OVER THE DAMPERS.

Stack Height 38.5 m Stack Diameter: 3.3m


FLOWRATE Am3/h 634,000 176,000 85,000

FLOWRATE Nm3/h 545,000 151,000 73,000

PRESSURE Ambient Ambient Ambient

TEMPERATURE oC 38°C 70°C Ambient in winter months

COMPOSITION: IMPURITIES: RANGE ppm w/w UNIT

Air % v/v +- 99% Dust Composition:... AS PER P3

Dust mg/Nm3 TO ATMOS LESS THAN 30mg/Nm³

Dust Burden kg/h

t/a

Other

INTENDED MEANS OF DISPOSAL: Holding Silo- bagged- pelletized

Discharged to atmosphere. Less than 50mg/m³

POTENTIAL EFFECTS: Non , when within stipulated environmental specifications

Ground level concentrations of dust in the local community. Zero

Notes:


M14 PROJECT


25. WG4 M14 Bag-Filter Dust at Stockpile - Fugitive Emissions


STREAM NAME: M14 Bag-Filter Dust at Stockpile - Fugitive Emissions

Reference WG4




AVAILABILITY 100%


FLOWRATE Dust t/h 0


PRESSURE Amb

TEMPERATURE oC Amb


kg/t

Wind whipping of dust


Full heavy metal and trace element analysis required. See baghouse dust P3


Dust emission when the dust is stockpiled on the stockpile SP4. This dust forms a fugitive emission into the atmosphere which impacts upon the site and local area, employees and local community.

POTENTIAL EFFECTS:


Notes:


M14 PROJECT


26. WG5 M14 Molten Slag Emergency Casting Emissions


STREAM NAME: Molten Slag Emergency casting Emissions Reference WG5



REFERENCE SOURCE: : K’enyuka Mass Balance 6 June 2008

Height: Ground level

AVAILABILITY of Slag carrier: 98% AMOUNT STORED In the slag casting Bed 100t


FLOWRATE SLAG t/h Included in

FLOWRATE inc Availability t/a Other fugitive emissions from Furnace operation

Very low

% of year emergency casting % 2

PRESSURE Ambient

TEMPERATURE oC 1450



% Fugitive Emission

kg/a

Casting into bay # # #

To be provided by the Airshed Study

#Heavy metal and trace element analysis required. See baghouse dust P3


Balance forms a fugitive emission which is discharged to atmosphere

POTENTIAL EFFECTS:


Notes:


M14 PROJECT


27. WG6 M14 Molten FeMn Slag casting at Stockpile - Emissions

PLANT NAME: FeMn Slag Stockpile Page

STREAM NAME: Molten Slag casting at stockpile Emissions Reference WG6




HEIGHT Ground level

AVAILABILITY 98% AMOUNT STORED IN Slag CARRIER 40t


FLOWRATE of Slag t/h 13.98


% of year casting % 100

PRESSURE

TEMPERATURE oC 1450


kg/t

Casting into dump #

To be provided by the Airshed Study Heavy metal and trace element analysis required. See baghouse dust P3


Slag cast in area about 10mx15m and quenched with water.

Fugitive emission which is discharged to atmosphere.

POTENTIAL EFFECTS:


Notes:


M14 PROJECT


28. WG7 M14 Molten Slag Pouring into Slag Carrier Ladle Fugitive Emissions


STREAM NAME: Molten Slag into Slag Carrier Ladle Emissions Reference WG7




Height Ground level

AVAILABILITY 98% AMOUNT STORED IN SLAG CARRIER 40t


FLOWRATE of slag t/h 13.98


% of year casting % 98

PRESSURE Ambient

TEMPERATURE oC 1450



% Fugitive Emission

Estimate

Casting into Slag Carrier

# # # - 0.0041t/h 35.14t/a

#To be provided by the Airshed Study To be provided by the M14 Project.

Full heavy metal and trace element analysis required. See baghouse dust P3


There is a fugitive emission as the slag is cast from the furnace into the Slag carrier ladle. A portion of emission is collected by secondary pollution hoods

Balance forms a fugitive emission which is discharged to atmosphere.

POTENTIAL EFFECTS:


Notes:


M14 PROJECT

SOLID WASTE SPECIFICATION SHEET

29. WS3 Bag Filter Dust to Stockpile


STREAM NAME: Bag Filter Dust to Stockpile Reference WS3




AVAILABILITY 98% Proportion of dust dumped: nil%


FLOWRATE t/h 0


PRESSURE Amb

TEMPERATURE oC Amb

COMPOSITION: % w/w IMPURITIES %w/w Mn (MnO 43%) Fe SiO2 MgO CaO ZnO

Particle Size Distribution: PM10 To be provided by the Metalloys APPA Study. INTENDED MEANS OF DISPOSAL:

Pelletizing plant will be functional. None will be stock-piled.

POTENTIAL EFFECTS:

Wind whipped dust emission and pollution.

Dust emission when the dust is dumped on the stockpile SP3. This dust emission into the atmosphere impact upon the site and local area, employees and local community.

Notes:


M14 PROJECT

SOLID WASTE SPECIFICATION SHEET

30. WS4 Slag to Stockpile


STREAM NAME: Slag to Stockpile Reference WS4

ANNUAL RATE: Product: HCFeMn 17.05t/h Date 31 May 2008



AVAILABILITY 90%


FLOWRATE t/h 13.98


PRESSURE

TEMPERATURE oC


MnO 25% TiO2 0.15

Fe0 0.2% P2O5 <0.01

SiO2 (A) 32% Total S 0.86

CaO (B) 31% Cr2O3 0.01

MgO (C) 7% V2O5 <0.01

Al2O3 (D) 8% BaO 0.20%

Basisity (B+C)/(A+D) 0.95 K2O 0.14

Na2O 0.24

To Particle Size Distribution including Dust

20mm x 40mm

PM10 and PM2.5 To be provided by the Metalloys APPA Study

<200Mesh (75µm) To be provided by the Metalloys APPA Study


Slag is discharged at the Pre-Metrec slag stockpile where it is quenched with water. It is crushed and screened, this generates a fugitive emission.

POTENTIAL EFFECTS:


Notes:


M14 PROJECT

LIQUID WASTE SPECIFICATION SHEET

31. WL1 Cooling Water losses and Sewerage


STREAM NAME: Cooling Water Reference WL1

ANNUAL RATE: 407 866t/a Water consumption Date 2007-06-21

CONDITIONS DEFINED AT Revision 0

REFERENCE SOURCE:

LINE NUMBER


FLOWRATE m3/h 49

PRESSURE

TEMPERATURE oC In/out 13/18

COMPOSITION : % UNIT IMPURITIES :ppm UNIT

Dissolved solids

Suspended solids

pH

Conductivity

Sewerage 1m3/h to sewage treatment plant


CCCW occasionally overflows and sometimes is dumped for maintenance purposes. It is dumped into the sludge water system.

POTENTIAL EFFECTS:

Notes:


M14 PROJECT

STOCKPILE SPECIFICATION SHEETS

32. SP1 Cast Ferro-Manganese


STREAM NAME: Cast Ferro-Manganese Reference SP1

ANNUAL RATE: Case; Product: HCFeMn 17.05t/h Date 2007-06-20


REFERENCE SOURCE : Metalloys Mass Balance 20 April 2009

AVAILABILITY 98% AMOUNT STORED 300t in casting beds


FLOWRATE t/h 18


PRESSURE Amb

TEMPERATURE oC Amb - 1350

CAPACITY t 500

Dimensions 17m long 6.2m wide Bulk Density 4.25t/m3

COMPOSITION % w/w IMPURITIES %w/w

See Product Spec sheet P1



% Fugitive emission

kg/a

Casting into Slag Carrier # # #

#To be provided by the Airshed Study


FeMn is tapped from the furnace into a ladle. After weighing it is cast into an open area and allowed to solidify. It naturally cracks as it cools. 13 – 15 castings are made each day and after 2 – 3 days several layers have been cast. At that point a front-end-loader breaks up the layers and loads them on to a truck. The truck conveys the product to the two handling department for crushing and screening into the various product size ranges.

POTENTIAL EFFECTS:

Dust and fume from breaking the Casting bed. These dust and fume emissions into the atmosphere impact upon the site and local area, employees and local community.

Notes:


M14 PROJECT

STOCKPILE SPECIFICATION SHEET

33. SP3 Cast Slag at Stockpile

PLANT NAME: Stockpile Page

STREAM NAME: Cast FeMn Slag Reference SP3




AVAILABILITY 98% Proportion going to dump 100%:


FLOWRATE t/h 13.98

FLOWRATE inc Availability

t/a 120 054

PRESSURE Amb

TEMPERATURE oC Amb

Dimensions ~15m wide ~30m long


See spec sheet P6


FeMn is tapped from the furnace into a series of ladles and the slag is separated. After the alloy is weighed the slag is poured into a mobile ladle and carrier. From there the slag is taken Metrec for alloy recovery (and recycle), and dumping of the slag. This causes a fume emission, and forms the slag stock-pile.

EMISSION FACTOR To be provided by the Metalloys APPA Study

POTENTIAL EFFECTS: Dust is generated by wind whipping of the slag stockpile. This dust emission into the atmosphere impact upon the site and local area, employees and local community.

Dust. Notes:


M14 PROJECT

STOCKPILE SPECIFICATION SHEET

34. SP4 Bag House Dust at Stockpile

PLANT NAME: Stockpile Page

STREAM NAME: Bag House Dust Reference SP4


CONDITIONS DEFINED AT: Site, ambient Revision


AVAILABILITY 98% AMOUNT STORED Nil


FLOWRATE kg/h nil

FLOWRATE inc Availability t/a Nil

PRESSURE

TEMPERATURE oC Ambient

CAPACITY t

Dimensions m Dia mHt


See bag-house dust WS3

PROPORTION OF DUST GOING TO STOCKPILE %: NIL



The Baghouse dust from the furnaces is collected in a sealed truck is and transported and dumped in a dedicated area.

EMISSION FACTOR Ref:

POTENTIAL EFFECTS: Dust emission when the dust is dumped on the stockpile SP3. This dust emission into the atmosphere impact upon the site and local area, employees and local community. .

Notes:


OTHER ITEMS

35. Emergency response procedure.

Procedures exist as follows:

EMERGENCY PROCEDURES See Ref 10.5

1. FIRE

2. GAS

3. EXPLOSIONS

4. RADIATION

5. BOMB SCARE

6. SPILLS

Procedures include what to do and muster points.


36. Further Studies That are being Considered by the M14 Project

No STUDY Code No. Yes/No

1. Hazard Study 2 x

2. Hazard Study 3 √

3. Study of Computer Systems √

4. Fire Reviews. √

5. Relief and Blow-down Studies.

6. Area Classification Reviews. √

7. Hazard Study of non-process hazards. √

8. Control and Operability Reviews. √

9. Pipe-work Registration Reviews.

10. Critical Machines Review. √

11.. Study of construction activities. √

12.. Plant trips and alarms. √

13. Major Lifting Equipment √

14. Reliability Studies. x

15. Mond Index x




19. Hazards in Construction PMS:068:01 √

20. Paving and Drainage PMS:068:02 √

21. Cable Routing Philosophy PMS:068:04 √

22. Relief Systems 1 & 2 ADG :053 x

23. Flaring Systems Process Safety x

24. Flowsheet PMS:068:05 √

25. Value Analysis ADG:041 x

26. Electrical Power Distribution Philosophy PMS:068:06 √

27. Control Philosophy PMS:068:07 √

28. Data Sheets for Key Systems and Equipment PMS:068:08 √

29. Room Data Sheets PMS:068:09 x

30. Engineering Line Diagram PMS:068:10 √

31. Noise PMS:068:11 √ complete

32. Trip and Alarm Philosophy PMS:068:12 √

33. Energy Efficiency Study √

Tim Knight

37.

s 07/01/2011 07:38

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age 126 of 131 m14 tech rev15d.docx

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of 32

.24/01/2011 M14 Tech Rev15d.docx

material to minimise the amount of precursors or organic matter is therefore a very important measure to prevent the formation of dioxins.

When such mixtures are cooled between the temperatures of 400o and 250oC for a time period of a few seconds; some references say a minimum of 2 seconds D&F may be formed. This envelope of temperature and time is required for dioxins formation, and if this envelope is avoided then D&F cannot be formed. Quenching gases through this temperature range in less than 2 seconds eliminates D&F formation.

The concentration of carbon compounds, chlorine and fluorine compounds will influence the quantity and particular species of dioxins but even very low concentrations are all that are required to produce infinitesimal but dangerous concentrations of dioxins. The toxicity of dioxins is so great that infinitesimal quantities still provide a hazard.

Off-gas from many processes may provide the necessary components for dioxins to be produced. This may include SAF for SiMn processes. The likelihood of dioxins formation in the SiMn process, is however, more dependent on the temperature time envelope.

The Significance of the Hazard

Since the alarm that was spread by Agent Orange and the Seveso incident questions have been raised as to the level of this hazard. The toxicity is not in doubt, but the likelihood of producing a toxic hazard is. There have been very few reports of dioxin toxicity incidents as a result of emissions from industrial activity. See Ref 10.18.

Dioxins Formation in the M14 Furnace

There is little to be found in the literature about dioxin formation in the submerged arc furnace, although there is information about dioxin formation in an electric arc furnace used for processing scrap.

It seems that there is a likelihood of dioxin formation if the feed to the electric arc furnace is mixed with scrap material. The scrap contains plastic and oil, all which contribute to the formation of dioxins.

In SAF manufacture of Mn alloy where the materials are supplied directly from the mine, with no impurities of plastic or oil, then it is likely that the formation of dioxins will be limited and emissions will be below the International accepted standard.

Dioxins are however relevant to the production of Mn alloy. Dioxins or their precursors may be present in some raw materials and there is a possibility of de-novo synthesis in furnaces or abatement systems. Dioxins are easily adsorbed onto solid matter and may be collected by all the environmental media such as dust, scrubber solids and filter dust.

However there is little in the literature to indicate that the formation and toxins is a serious consideration in Mn alloy production.

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Although dioxins are destroyed at high temperature (above 850 °C) in the presence of oxygen, the process of de-novo synthesis is still possible as the gases are cooled through the “reformation window”. This window can be present in abatement systems and in cooler parts of the furnace e.g. the feed area. Care taken in the design of cooling systems to minimise the residence time in the window is practised to prevent de-novo synthesis. Sufficient oxygen needs to be present in the hot gases and in the Mn alloy process oxygen is excluded from the off gases and they are quenched in the venturi scrubbers limiting and probably eliminating the formation of D&F. After that the gases are passed to the Elgen boiler which ensures complete combustion and further elimination of D&F.

If there is a likelihood of the synthesis of dioxins in the Mn alloy furnaces then there are various techniques that could be employed depending on the application, to be incorporated into existing processes. The most effective and economically viable technique will depend on the specific site, safety aspects and operational stability as well as economic factors are taken into account. Emission levels of better than 0.5 ng/m3 TEQ can be achieved using one or more of these techniques to the clean gas side of the system. Lower values better than 0.1 ng/m3 TEQ can be achieved by one or a combination of these techniques should it be necessary.


39. Stack Height Relative to Any Nearby Building

It is generally accepted that if a stack complies with the criteria in Good Engineering Practice (i.e. 2.5 times higher than ANY nearby building) then building downwash is unlikely to occur (US EPA, 1985). This guideline will result in a stack height of 100 – 115 m. Building downwash will likely result in high on-site concentrations that is unlikely to affect surrounding communities. Occupational (on-site) guidelines/limits are generally much higher than ambient guidelines and high on-site concentration (due to building downwash) might still fall within the occupational guideline value even though it might exceed ambient guidelines/limits. In determining minimum stack height it might be prudent to use ambient guidelines /limits as a conservative measure and to only consider the pollutant emitted from the stack with the strictest guideline/limit value.

In calculating a minimum stack height, various criteria need to be considered i.e. what pollutant, exposure periods and type of exposure (occupational or environmental) etc. To determine this we might have to do small scale dispersion modelling or screening.

Reference: United States Environmental Protection Agency (US EPA), 1985, Good Engineering Practice Stack Height. EPA 401 KAR 50:042. URL: http://www.epa.gov/scram001/guidance/guide/gep.pdf.


40. M14 Raw Materials Handling – Dust removal points

TERRA PACIS ENVIRONMENTAL METALLOYS M14 FURNACE … · KNIGHTS ENVIRONMENTAL TERRA PACIS...

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