INTRODUCTION

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INTRODUCTION

Cement industry is one of the important industries to country development in the

light of the main important basis for construction industry and also the important

indicator showing domestic economic growth. In the past, the domestic demand

of cement used to be up to 36 million tons. But, the severely negative effects

from economic crisis in 1997 have caused real estate and construction industry

subdued; the domestic demand of cement has shrunk and been in oversupply

atmosphere.

Until 2001–2003, the government has launched many economic actuating

policies. This has made real estate and construction industry recovered and the

demand of cement has been increasing gradually from 21 million tons in 2001 to

25 million tons and 26.82 million tons in 2002 and 2003 respectively; and the

price level is higher in line with increased production cost.

Cement Industry originated in India when the first plant commenced

production in 1914 at Porbandar, Gujarat. The industry has since been

growing at a steady pace, but in the initial stage, particularly during the period

before Independence, the growth had been very slow. Since indigenous

production was not sufficient to meet the entire domestic demand, the

Government had to control its price and distribution statutorily. Large quantities

of cement had to be imported for meeting the deficit. The industry was partially

decontrolled in 1982 and this gave impetus to its pace of growth. Installed

capacity increased to more than double from 27 million tones in 1980-81 to 62

million tones in 1989-90.

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The cement industry responded positively to liberalization policy and the

Government decontrolled the industry fully on 1st March 1989. From 1991

onwards cement industry got the status of a priority industry in schedule III of

the industry policy statement, which made it eligible for automatic approval for

foreign investment up to 51% and also for technical collaboration on normal

terms of payment of royalty.

After the globalization and liberalization of Indian economy, the cement

industry has been growing rapidly at an average rate of 9 per cent. The country

is now the second largest producer of cement in the world next only to China

with a total capacity of 188.97 million tones. Additionally, in the last two

decades, the industry has undergone rapid technological up gradation

and growth, and now, some of the cement plants in India are comparable

to the world’s best operating plants in all respects.

Till a few years ago India was importing cement from other countries, as the

production could not meet the demand for the whole country. Now the tables

have turned as India has started exporting large quantities of cement and clinker

to Bangladesh, Nepal, Sri Lanka, Maldives, Mauritius, Africa, Seychelles,

Burma, UAE, and Singapore etc.

India is today the second largest producer of cement in world with an

installed capacity of close to 188.97 million tones per year. 95 % is

consumed domestically and only 5% is exported. Demand is growing at

more than 10 % per annum. More than 90 % of production comes from

large cement plants. There are a total of 130 large and more than 350

small cement manufacturing units in the country. More than 80% of the

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cement-manufacturing units use modern environment friendly “dry”

process.

Today total number of cement companies in Indian market are 47,having

number of cement plants 139, the installed capacity of large plants is

188.97 million tones and cement production during 2007-2008 was

168.31 million tones

The forms of cement produced: -

Ordinary Portland Cement ( OPC )

Portland Pozzolana Cement ( PPC )

Portland Slag Cement ( PSC )

Major players in Indian cement sector:-

ACC

BCL Cement

Gujarat Ambuja Cement

Ultratech Cement

India Cements

Century Cements

Jaypee Group

Madras Cements

Birla Corporation Limited

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INTRODUCTION OF BIRLA CORPORATION LTD.

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Overview

Founded in1919 by the visionary industrialist Shri G.D. Birla, at the

outskirts of the Kolkata, Birla jute manufacturing company Ltd. Was the first

company of the Birla Industrial Conglomerate. Under the stewardship of his

nephew Shri M.P. Birla, the company diversified and expand its business

interest beyond jute, to encompass cement PVC coated fabric, PVC floor

covering and auto trims.

After the demise of Late Mr. M.P. Birla in 1990, his wife, Mrs.

Priyamvada Birla took over as chairman of Birla Corporation and continued to

lead the company till her death on 3 July 2004. She was an entrepreneur of

distinction strong business acumen and, under her leadership, the company

crossed the Rs. 1,300-plus turnover mark.

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The company, renamed Birla Corporation Limited, to reflect the wide

range of operation, is the flagship company of the M. P. Birla group. The

strategic focus of the company has been on steady growth by developing and

assimilating technologies of tomorrow to manufacturing an ever widening range

of value-added product, while striving for complete customer satisfaction in

India and abroad. Birla Corporation Limited is proud of safe work practice

followed at all its factories and godowns. As an enlightened corporate citizen,

Birla Corporation Limited is keenly aware of social responsibilities too, and

provide education and health care facilities for its employees, their families and

the community at large.

Its export in 2004-05 stood at Rs. 85.28crores. Over the year, BCL’s business

has grown from strength to strength.

1.1 Overview : Cement Industry

The cement division of Birla Corporation Limited has seven plants, two

each at Satna (M.P.) – Satna Cement Works & Birla Vikas Cement, Chanderia

(Rajasthan) – Birla Cement Works & Chanderia Cement Works, and Durgapur

(W.B.) – Durgapur Cement Works & Durga Works & Durga Hitech Cement and

one at Raebareli (U.P.) the total capacity of these plants is 57.80 lakh tones. This

plant manufacture varieties of Cement like Ordinary Portland Cement (OPC),43

& 53 grade, Portland Pozolanna Cement (PPC), Fly Ash based PPC, Low Alkali

Portland Cement, Portland Slag Cement, Low Heat Cement and Sulphate

resisting Portland cement.

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The cement is marked under the brand name of Birla Cement

KHAJURAHO, Birla cement CHETAK, Birla cement and Birla premium

cement, bringing the product under a common brand of Birla cement while

retaining the niche identity of Khajuraho (for the OPC product of Satna), Chetak

(for OPC product of Chanderia) and Samrat of blended cement, i.e. PPC & PSC,

for all the units.

The division export large quantity of cement to Nepal and Bangladesh,

under the brand name of Khajuraho, Samrat, Camel, Royal tiger.

The special variety of SAMRAT cement, begun produced by the company is

ideal for mass concrete. RCC / pre-stressed – pre-cast structure (for reduced

thermal crack), increased water tightness of concrete, increase resistance to

Sulphate soils and aggressive water and increased resistance to alkali aggregate

reaction beside corrosion resistance properties.

SCW, BVC and DVC have received the ISO 9001-2000 quality system

certification, covering the entire range of production and marketing. SCW &

BVC have received the IS / ISO 14001 certificate, an international recognition

for “Implementation of Environmental Management System” BVC have got the

“Best productivity of Performance” award from NPC during 1986-88, NCCBM

recognized it for “best in energy performance” during 1986-87. It received

“National Safety Award” for outstanding performance in achieving the longest

accident free-period during 1994. In 1996, it received the runner cup under

scheme –1 of National Safety Award, for the lowest average frequency rate

accident. BVC has also received “Fuller Energy Conservation Award” as first

for “Lowest Thermal Energy Consumption” (for group B’ category plants) for

three consecutive years i.e. 1997-98, 1998-99, 1999-2000. SCW has been

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adjudged by NCCBM the “Best In Energy Performance” during 1993-94, 1994-

95, 1995-96, 1997-98. It was the second best for “Improvement in Energy

Performance” during 1996-97. SCW has also got “Fuller Energy Conservation

Award” as first prize for “Lowest Thermal Energy Consumption” (for group A

category plants) for three consecutive years i.e. 1997-98, 1998-99, & 1999-2000.

BCW & SCW have received the ISO 9001-2000 certification for Quality

Management system, covering the entire range of production and marketing and

also have received the IS / ISO: 14001 certification for BCW & CCW have

bagged various awards from NCCBM. CCW have received the “Best

Productivity” award during 1989-90 & 1993-94. NCCBM recognized it for

“Best Improvement in Thermal Energy Performance” during 1993-94. It has

won “Lal Bahadur Shastri Memorial National award for “Excellent Pollution

Control Implementation” for 2001-02 by International Greenland Society. BCW

was awarded “Best Improvement in Energy Performance” and “Best

Improvement in Thermal Energy Performance” during 1992-93.

The Rajasthan Government gave “Bhama Shah Samman” it during 1996.

VEC-IIT Madras chose Chanderia unit for excellence in “Improving Machinery

Health Condition” during 1997. VEC, Chennai chose Chanderia unit for

sustained implementation of condition monitoring and continued Machine

Health Improvement Award during 2001-02. The Central Board awarded the

“Worker Education Trophy” for worker education, Udaipur Ministry of Labor,

Government of India for excellent contribution and Implementation of workers’

training during 1998-99 and again in 2001-02. BCW has received excellence

award in Cement Sector from the Rajasthan State Council, Jaipur, during 2002-

03.

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The DWC plant has received IS / ISO 9001-2000 license for Quality

Management system certification (accredited by road voor accredited

Netherlands). The capacity of the 6,00,000 tons plant increased by another

10,00,000 tons, making it the largest plant in West Bengal. The new grinding

unit, Durga Hitech Cement, has one ball mill of 165 TPH capacities. This

environment-friendly project, commissioned in 2005-06, utilized thermal power

station fly ash to produce PPC. DCW recorded 114% capacity utilization in

2004-05, emerging as the highest growing cement unit in the eastern region.

Cement plant were set up in MP and Rajasthan and Grinding units in West

Bengal and UP.

Satna Cement Works - 1959

Birla Cement Works - 1967

Durgapur Cement Works - 1974

Birla Cement Works - 1982

Chittor Cement Works - 1986

SCW-Conversion Plant - 1989

Raebareli Unit - 1998

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Late Shri M.P.Birla Late Smt. Priyamvada Birla

Mr. P.S. Marwah

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President of Satna Cement And Birla Vikash Cement Plant satna (m.p.)

Birla Corporation Limited is a multi- product conglomerate.

It plays significant roles in the Cement, Jute, PVC floor Covering,

Auto Trim and Steel casting industries.

The concentric around the triangle represents this very multi-

dimensional nature.

The apex of the triangle is a visual representation of the force that

drives the entire corporation – the unifying force in search of

excellence.

The circle represents the inspiration to explore new frontiers of

growth.

MANAGEMENT

The day- to- day management of the company is being looked after by the Chief Executive Officer, Shri B.R.Nahar who is assisted by a team of highly qualified professional persons.

Chairman

Late Shri R.S. Lodha

ED & CEO

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Shri B.R.Nahar

Board of Directors

Shri N.K. Kejriwal Smt Nandini Nopany

Shri Harsh V. Lodha

Shri Pracheta Majumdar

Shri Vikram Swarup

Shri Anand Bordia

Shri B.B. Tandon

Shri D.N.Ghosh

CHIEF FINANCIAL OFFICER

Shri P.K. Chand

ACTING COMPANY SECRETARY

Shri Girish sharma

AUDITORS

H.P. Khandelwal & company charted Accountants

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Achievements

1. SCW, BVC & DCW have got ISO 9002 quality certification, covering the entire

range of production & marketing.

2. Best Energy performance award in 1995-96 & 1994-95.

3. Second best improvement in energy performance award in 1995-96.

4. Top export award in 1994-95.

5. First prize in productivity to CCW in 1993-94.

6. Special Export award in 1993-94.

7. Best Energy performance award to SCW in 1993-94.

8. Special export in 1992-93.

9. Top export award for 1990-91 & 1991-92.

10. Second Best Performance in 1991-92.

11. Best Performance award in 1989-90.

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AWARD EARNED BY SCW AND BVC

S. NO. AWARDS AWARDED BY YEAR UNIT

1. Best Energy Performance

Award

NCB, New Delhi and

Ministry of Power

Govt. of India

1986-87

1993-94

1994-95

1995-96

1996-97

1997-98

BVC

SCW

SCW

SCW

SCW

SCW

2. Fuller Energy Conservation

Award

M.P. Chamber of

Cement Manufactures

Association.

1997-98

1998-99

1999-00

2001-02

1997-98

1998-99

SCW

SCW

SCW

SCW

BVC

BVC

3. Best Productivity Award National Productivity

Council, New Delhi

1987-88 BVC

4. Export Award CAPEXIL, Kolkata 1990-91

1991-92

1993-94

1994-95

1996-97

1997-98

2001-02

BVC

BVC

SCW & BVC

BVC

BVC

BVC

BVC

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5. National Safety Award Ministry Of Labour,

Govt of India

1994 BVC

6. ISO-9001 for quality

Management

RWTUV, Germany Since July

1994 Renewed

every year

SCW & BVC

7. IS / ISO-14001 for

Environment Management

BIS, New Delhi Since Sept.

1999 Renewed

every 3 year

SCW & BVC

8. Sagmania Mines Safety

Award

DGMS 1997-98

9. Mines Environment & Mineral

conservation Overall

Performance

ISM, Dhanbad 1997-98

2002-03

10. Best Energy Conservation

Implementation Gold Award

Rajiv Gandhi

Memorial National

Award

Oct 2004 SCW

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Product Profile

At Satna Cement Works & Birla Vikas Cement the dry process of Cement

production followed which is termed as a modern technology. The Entire

Manufacturing process is controlled through a microprocessor based

programmable logic control system to maintain a constantly uniform quality of

Cement & high rate of production. The entire operation of plant is controlled in

a single control room. SCW plant, which was initially, a plant using a wet

technology for cement production was changed an to a dry one in the year 1989.

These modern plant have also taken adequate core to prevent the environment

policy & dust nuisance to its surrounding areas. These cement mills have

electrostatic precipitator (ESP) installed to check dust emission & to ensure

health hazard free atmosphere.

Both the plant uses the global technology for the production of goods &

consistent quality cement. The Stacker Reclaimer Technology & the alkali by

pass system along with other sound technology make the manufacturing process

of Birla Cement Khajuraho a highly competitive & unique one.

The various varieties of cement produced at these plants are:

1) Ordinary Portland Cement (33, 43, 53 grade)

2) Portland Pozzolana Cement (PPC)

3) Low alkali Cement.

4) Sulphate resistant Cement.

5) Special Cement for Indian Railway Sleeper (IRS-T-40)

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The benefits of using high quality cement manufactured by the company are :

1) Ideal for mass concrete structure.

2) Reduce thermal cracks.

3) Increased water tightness of concrete.

4) Higher fineness, ideal for plastering.

5) Increased resistance for sulphate attack & aggressive water.

6) Increased resistance to alkali aggregate reaction.

7) Improved durability.

General Review

The year 2005-06 was the most successful year of the company since its

inception in terms of financial performance. The company, maintaining stable

growth, posted 7% increased in turnover to Rs. 1433.44 crores as compared to

Rs. 1342.64 crores in the pervious year. The interest cost further reduced during

the year Rs. 13.62 crores as compared to Rs. 21.69 crores in the previous year.

Profit before tax recorded at 54% jump when up to Rs. 144.09 crores from Rs.

93.70 crores in the previous year. The company recorded the highest ever

turnover, cash profit, profit before tax and profit after tax during the year. The

management continued its effort to control and reduce cost across all the

division at all levels. Profitability of the company improved due to increase in

volumes, sales price realization and better operating efficiencies.

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Corporate Matters

Thermal power plant of 27 MW each for captive use at the company’s

units at Chanderia and Satna were installed and put to use during the year. These

power plant are expected to reduce the power cost significantly and increase the

operational efficiencies.

The company’s new unit: Durga Hitech Cement, adjacent to the existing

plant at Durgapur, West Bengal was also commissioned for commercial

production on 24 December 2005.

The company has taken up steps to enhance the capacity of clinker

production at its plant in phases. The project once executed, will result in saving

in fixed running cost and existing infrastructure like railway siding and power

plant will also be used optionally.

Effort to shift Soorah Jute Mill’s to Birlapur from heart of Kolkata city for

economic viability, operational efficiencies and environmental issues are

continuing.

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Cement Manufacturing process1-Mining: The cement manufacturing process starts from the mining of lime stone , which is the main raw material for making cement. Limestone is excavated from open cast mines after drilling and blasting and loaded on to the dumpers which transport the material and unloaded into the hoppers of limestone crusher.

2-Crushing Stacking & Reclaiming of Limestone: The l/s crusher crush the Limestone to minus 80mm size and discharge the material onto a belt conveyer which take it to the stacker via the bulk material analyser. The material is stacked in longitudinal stock piles . Limestone is extract transversely from the stockpiles by the re-claimers and conveyed to the Raw Mill hoppers for grinding of raw meal.

3-Raw Meal Drying/Grinding & Homogen-ization: Reclaimed l/s along with some lat-rite stored in their respective hoppers is fed to the raw mill for fine grinding. The hot gasses coming from the clinkerisations section are used in raw mill for drying and transport of the ground raw meal to the electrostatic precipitator /Bag house, where it is collected and then stored and homogenized in the concrete silo. Raw meal extracted from the silo(ne called kiln feed ) is feed to the top of the pre-heater for pyro-processing.4- cooling: Hot clinker discharged from the kiln drops on the cooler and gets cooled.5-Clinkerisation: Cement clinker is made by pyro processing of kiln feed in the pre-heater and the rotary kiln. Fine coal is fires as fuel to provided the necessary heat in the kiln and the pre-calciner located at the bottom of the 5/6 stage pre-heater. Hot clinker discharged from the kiln drops on the gate cooler and gets cooled. The cooler discharged the clinker onto the pan / bucket conveyer and it is transported to the

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Conveyer Belt

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MiningThe major raw material for cement manufacturing is limestone. Limestone is excavated from open cast mines after drilling and blasting and loaded onto the dumper which is transported the material and unloaded into hopper of the limestone crusher.

Equipment Used in mining:1. Compressor drilling machine.

2. Shovels/Excavators-for lifting material onto dampers.

3. Dumper- for carrying material.

4. Built-dozers.

5. Pay-loaders.

Explosive:1. Ammonium nitrate(Fuel oil)

2. Nitroglycerine.

3. Ammonium nitrate and slurry explosive.

Steps of Mining:1. The first step of mining l/s the l/s has been located.

2. Limestone mining is to remove the mines.

3. The third step is to be taken as drilling.

4. After drilling blasting is done.

Drilling and Blasting:1. The large hole blasting method is not pre-dominated in quarrying

in open pit.

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2. The depth of the wholes are more then 12m and 100-150mm dia.

Lime Stone CrusherLime stone crusher is the lead role playing equipment in this section. The raw lime stone is carried out from the mines is introduced to the lime stone hopper through whole pack dumper of capacity 32 tons. The feed inside the impact crusher first enters to the crushing chamber with help of apron feed encounters. The impact bars mounted over the rotor &revolving with the circum-frencial velocity of 30-40 m/sec. Material are blown bars and stick on a impact arm. Here materials are initially install to hold these grinding bars. The squire impact arm is install just behind the impact path and having 12 liners. When the material get crushed enough for transportation towards stacker. A bag house is also installed to control the dust loss and pollution control.

Equipment Used in Crushing:1. Crusher.

2. Apron conveyer – for feeding l/s to crusher.

3. Bag filter – for collecting dust.

4. Belt conveyer- for transporting crushed material.

This section is worked with following equipment:1. Impact crusher.

2. Magnetic separator

3. Limestone stacker& re claimer

4. Bag filter

5. Apron feeder

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6. Limestone hopper & late rite hopper

The important mode of transportation in this section is belt conveyer.Main component of impact crusher:

Housing: housing of impact crusher is of studly steel fabricated and consists of three parts.

Rotor: The rotor in the impact crusher is of s-type construction secured to the shaft by locking assembly. The blow bar placed in to the rotor from the side and are secured against lateral moment by a suitable locking device at the extreme end. The rotor is dynamically arranged to avoid any undesirable stress on the bearing.

Blow bar: Blow bar is made from high quality alloys steel. After the certain period in operation the blow bar can be taken out from the rotor and turned to other side or exchange.

Wear plates: housing is fitted with the resistance wear plates which are secured in position by special fastners which can be changed as and required.

Impact Arm: The impact crusher is fitted with the impact arm. The impact arms are each suspended in the housing parts by means of knock out spindle and can be adjusted the desire gap setting from out side.

Hydraulic system: Impactors are depends on their size normally supplied with a hydraulic arrangement for setting of gap for grinding path lifting of the rear top housing.

Magnetic Separator: A magnetic separator is installed just above belt conveyer between crusher and stacker. When the magnetic material are comes along with lime stone .they get se-prated by

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magnetic separator. In the magnetic separator a permanent magnet and a continually moving belt being fin use. Magnetic materials are attached by magnet due to cont. rotating of belt , material get se-prated on removal of magnetic field.

Gamma Matrices: A gamma matrices analyzer being used for analyze the chemical composition of lime stone. It is also known as cross belt analyzer. In gamma metric analyzer we are using specially gamma rays, the gamma rays are fall on material and return back, according to absorption rays in to material we can determine the chemical composition of lime stone .

LIME STONE STACKER:-A limestone stockpile (closed stock pile) has been proposed at the plant site with stacker re-claimer. The re-claimer will help in feeding a homogenized limestone by mixing rich quality LS with low grade mineral. By installing a re-claimer in the plant, the plant can achieve not only quality raw material input but also the conservation of natural resources by utilizing low-grade raw material.

There are two main methods being used for stacking of lime stone in cement industry. They are……..

1. Chevron Method2. Windrow Method

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Pulverizer :-

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LIME STONE RECLAIMERRe-claimer which is used in our industry is bridge type scrapping re-claimer. The bridge on which the racking down device is mounted accommodates a scraper chain conveyer whose blades shift the dislodged material along to collecting belt conveyer that extent along one edge of stack pile. Re-claimer having harrow assembly. Re-claimer moves on a track for fast travel a.c. Motor being used and for slow traveling d.c. motor being used. Harrow is moves to and fro motion on rack car which is driven by a motor. A limit sensor is installed for reverse and forward motion of harrow assembly. According to pile we can adjust the inclination of harrows. When harrows are moves they are scrap the material of each layer of stockpiles and material slides down due to gravity. A scraper chain take out the material and fed to belt conveyor material now get transported forwards limestone hoppers.

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Raw mill:

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Blending Of Raw Meal:The meal from the mill need storage and blending become different chemical composition of lime stone in different lot. They may vary the quality of lime stone.

Silo: Silos are huge construction of concrete and iron with aeration units to stone and blend the fine material such as raw material.

.Continuous Fluidize Silo: The raw meal is completely fluidized by admission of compressed air through the suitable inlets at the bottom of the silo. The air penetrates the mass of raw meal into the silo and reduces the inter particle friction forces. A circulatory motion is formed and thus homogenization is take place.

Operation of Raw Mill: When the Limestone feed is started with la-trite rollers get down & the grinding start.The grinded material is sucked up through the

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classifier by the help of hot gases .The reject material from the classifier is sent back to the grinding table by the help of reject group. The remaining fine material is sent to ESP & ESP reject material to silos. So total three types of material is falling on grinding table during running:-1)-Mill feed2)-Classifier reject 3)-Mill reject

SILOIt is the large storage of Raw mill which comes from the Raw Mill. It is made of concrete & can store Raw mill for long time.

Purpose:- It’s main purpose is to homogenize the raw mill. One of it’s main purpose is to also store raw mill for long time.

Construction:-

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It mainly a large structure made of concrete. It contains following devices:-1)-Air Compressor2)-Large Air Ducts3)-Pneumatic Valves4)-Exhaust Fans on the top

Preheater Purpose:- To increase the temperature of rawmill material through the incoming hot air from kiln & transfer air duct.

Working Principle Of Preheater As the name explains “Pre-heater Tower” is place to use for preheating the raw material. The material which comes from c.f. silo in other words pre-heater is a device in which heat transfer takes place from hot gases which comes from kiln due to counter current flow of material and hot gases. The raw mill is heated about 850oc before it enter it the kiln pre-heater with calcined system is most economical and hence the length of kiln is reduce pre-heater in Unit-1 and five stage in unit-2 with separator line calciner. These suspension pre-heaters are work in kiln string & pyro string with pre-calciner string successfully.

Main part of suspension Pre-heater:1. Cyclone: The cyclone is use for separation of raw meal from

gas flow. For improving the separating efficiency of cyclones of top most pre-heater stage. We have designed as double separator.

2. Gas Duct: The gas ducts is to join the individual cyclone stages to each other. The raw meal coming from next higher

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stage and in the gas duct underneath. The raw meal particles are entering by the upward flowing gas stream and taken to the next cyclone. The heal exchange is achieved by con-current flow. The gas ducts b/w stage 1 and 2 consist of the cylindrical suction.

3. The Double Flow Box: These are used for raw meal pipes in pre-heater system the flaps are consists in such a manner that a minimum flow of raw mill is always maintained. The full material causes a upward and downward moment of the pendulum flaps and thus and upward and downward rocking motion of the lever arm with counter weight penetrating the single flaps. The upward and downward forces of flaps is remains constant.

4. Raw Material distributor: It is integral part of raw meal ducts and spits a downward flowing stream of raw meal in to raw

meal duct. Basically the distributor has a two fold function.

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Calciner:The main purpose of the pre-calciner is to let the calcinations process take place out side the rotary kiln. It causes in sufficient reduction of thermal load of the kiln burning as approximately 60% of total fuel is burn in to calciner. This has made possible to increase the production in the given size to about double compared to a conventional dry process kiln with suspension pre-heater.The calciner consists of a vessel lined with heat resistance bricks. Calciner has three inputs and one output.

Input- 1. Fuel as Pulverized coal.2. Preheated material to approx 800oc

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3. Hot gases from kiln/coolers at 800oc

Output- Hot gases including combustion products and co2 from the calcinations process and material in form of dust carried with the hot gases.

Lime Stone Tablet Maker :-

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Rotary kiln:Purpose:-

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Kiln is cylindrical rotary equipment rotating on supporting rollers at about 3.5 RPM. Discharge in its completing calcinations reaction. Firing is done from kiln outlet with the help of burner pipe.

Construction: Kiln can be divided into :-

a. Kiln inlet (consist seal, grease pump, lines, cylinders etc)

b. Girth gear(Gear, pinion, spray system)

c. Thrust roller(Hydraulic cylinder, oil line)

d. Supporting roller& tyre (Consist of bearing, chair plate, bolts etc)

e. Kiln outlet seal(S.S shims, crown shell, seal)

f. Burner pipe(consist of air pipe, coal pipe, diesel pipe etc)

Kiln inlet: Kiln inlet is seated by sealing arrangement. Greasing is done by pneumatic pump seal. It consist of 10-14 segment so it can be mounted and disassembled from kiln inside. A conical section forms an extension of the inlet ring. A brick retaining ring has been mounted at the end of conical section.

Girth Gear: Kiln is rotating by Gear – pinion arrangement. Girth gear is mounted on kiln with the help of spring plates.

Thrust Roller: The function of thrust roller is to control axial moment of kiln in both upward & downward.

Supporting Roller & Tyre: Supporting roller are for support of kiln. They are in contact with tyre which are fitted in kiln shell.

Kiln Outlet: There is a sealing arrangement in kiln outlet.

Burner Pipe: It is for firing of fine coal into the kiln. Air is controlled by damper and fine coal by solid flow meter.

Kiln cooler:Clinker cooler has two main function to perform. They are:-

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1. To cool the hot clinker quickly.2. To provide necessary air for burning of coal in pre-calciner and

kiln.

After introducing of red hot clinker into the cooler, mechanically driven gates moves it to the rear end of cooler. Three pair of gates are installed inside the cooler. A single pair consist of fixed gate and movable gate. Too and fro moment of movable gate pressurized which cools it quickly. Clinker cools down gradually as it moves, due to the air blow by the fans which is taken from the atmosphere. Air falling over clinker is highly pressurized which cools it quickly. Clinker escaping out of the cooler is fed to a hammer crusher, since lumpy material requires crushing. Crushed material is transported to clinker silo through deep bucket conveyor. Temperature of clinker escaping out of cooler is about 208oc.

Grate Cooler operation:

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The grate cooler operates with a cross current principle in which the clinker is moved across the grate while cooling air blow in from below through the grate and clinker layer. The hot clinker falls from kiln and forms clinker bed on he grate and transported through the cooler over alternatively fixed and reciprocating grates. At the inlet of first great clinker is quenched and spread evently across the cooler width by the increased cooling air. The grate is fabricated to be as possible to obtained a thick clinker layer and a uniform distribution of air through the clinker bed in the interest of heat recovery. During the clinker transport from the cooler a part of dust and small size clinker is falls from the grates and collected into hoppers under the grates. The drag chain and rotary air lock system fed these clinker and dust in clinker transport system. A dust collection ESP is also installed beside the cooler known as cooler ESP. Exhaust gases from collection is fed to the ESP for dust collection.

Grate cooler consist of:- Cooling grate Plates Standard Plates Cooling housing Drive unit Grate aeration system Clinker crusher Conveying unit(DBC) Cooling fan

Model of Lime Stone Crusher :-

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Coal Mill:

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The coal mill works for producing the pulverized coal for burning to increase the temperature of kiln, pre-heater, raw mill .It works as same as raw mill for lime-stone & latrite mixture {Raw mill} grinding, & the coal mill grind & transfer the coal to the furnace for burning. The raw mill is grounded dried swept away by fan through the separator to bag filter or ESP. finally it is stored in to the fine coal bin hot air for coal mill is supplied by cooler exhaust hot gases or pre-heater outlet gases before GTC circulation. The function of coal mill is to ground suitable grate coal and for feeding the same in to the kiln and calciner in fluidized form. Coal from stock yard is fed for stacking and reclaiming in to the stacker and re-claimer. Pre-homogenized raw coal is feed in to the coal mill hopper with the help of belt conveyer. The raw is then fed to the coal mill VRM via weigh feeder, drag chain and screw conveyer.

Important Parameters Of Coal:

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Residue on 90 micron=18-20% Residue on 212micron=0.4-1% Moisture =1.5% Volatile Matter =20-30% Ash content =28-32%

Coal Mill:- Coal Mill is an important integral part of cement plant. Here large size of approx size 600mm, is ground fine to the size of 90 micron. Coal from coal mill is used to feed kiln and calciner. Outlet tem of coal from coal mill is different in different seasons. It is 70-750c in dry season and 80-840c in rainy season. Coal from mines is initially crushed at crusher site. Coal is then sent to stacking making mixture homogenized. Reclaimer picks up the coal and coal is fed to the coal mill hopper through belt conveyer. Coal taken out from hopper is feed inside VRM with the help of a screw conveyer which is mounted just below the hopper. Coal inside VRM is grounded between roller and table. Hot air from cooler ESP fan is taken inside VRM and is used for drying of coal. Fine coal from VRM moves to the cyclone, where most of the coal is separated from air and the coal which does not get collected due to ultra fine size is separated with the help of ESP. LV separator is for separating coarse and fine particles.Now, coal is fed to screw conveyer through rotary lock, which transport it to the FK pumps. Two FK pump delivers material to the storage bins.

There are two Storage bins, They are:-1. Kiln Bin2. Pre-calciner Bin

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Fine Coal is then transported to the kiln and pre-calciner by kiln firing FK pump and pre-calciner FK pump respectively.

Classifier: A classifier is the top most rotary part of the vertical roller Mill . Here classification of materials occurs .Fine particles pass through classifier and course particles are rejecter and recycled for regrinding. According to the fineness required speed of the classifier rotor can be adjusted.

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Lime Stone Regrinder:-

QUALITY CONTROL IN CEMENT PRODUCTION

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Quality Control

Efficiency quality control is error prevention rather than error

detection. Online reaction to special cause of variation will lead

to progressive improvement in the process, performance and

cost. Fundamental improvement in quality results from testing

rational prediction about special process using statistical

method. The effective pursuit of quality permanent commitment

through out an organization.

Pitfall of quality control

Pitfall of the successful implantation of the permanent quality

improvement culture are:-

1. Lack of top management support.2. Lack of middle management support.3. Commitment to only department.4. Haphazard approach a little of this and that with no

meaning change in the system.5. Measurement of success and guidance program on the

basis of short-term profile.

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Cement :-

Cement is a word given to a powder material which initially has

plastic flow when mixed with water but has the property of

setting hard solid structure in the several hours with varying

degree of strength and bonding properties.

Natural is a mixture of burnt silicate and lime. It was discovered

by Joseph Aspdin an English brick layer in 1924. This Cement is

called Portland Cement and now a day prepared artificially.

Properties of Cement

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It gives strength to the masonry.

It is an excellent binding material.

It is easily workable.

It harden early.

Types of Cement

A. Ordinary Portland Cement (OPC)

It is of 3 types

1. 33G

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2. 43G

3. 53G

B. Pozzolana Portland Cement (PPC)

Uses of Cement

At present the cement is widely used in the construction of various engineering structure. It has proved to be one of the leading engineering materials of modern time and has no rival in production and application. Following are possible uses of cement:-

1. Cement mortal for masonry work, plaster etc.2. Concrete for layering floor, roof, construction

lanters, beams weather shed stairs pillars.3. Construction of important engineering structure

such as bridges, culverts, dams, tunnels, storage reservoir, light houses, dock etc.

4. Construction of water tanks, well, tennis court, septic tank, lamp post, roads, telephone cabins etc .

5. Making joints for drain and pipes.6. Manufacturing of present pipes, piles, garden seats,

artistically design urns, flower pots, dustbin fencing post etc.

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7. Preparation of foundation, watertight floor, footpaths etc.

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