PRESENTATION ON PROJECT DESIGN

1. SUDIP KUMAR DAS – 20113320022. HASAN SHAHRIAR SABIT – 20113320033. FARHANA MUKUL ARCHI – 20113320064. AFIA ANJUM MEEM – 20113320165. MONIMUN NAHAR MUNNY – 20113320186. MD. GALIBUR RAHMAN – 20113320267. SADDAM HOSSAIN – 20113320318. MD. SARWAR KAMAL – 20113320379. SHOVON MAHMUD PAYEL – 201133205110.SOURAV BARUA – 201133205511.OMIO RANI DAS - 2011332064

PRESENTED BY:

Cement Overview*Cement was first invented by the Egyptians. Later reinvented by the

Greeks and the Babylonians who made their mortar out of lime.

* In 1824, English inventor, Joseph Aspidin invented Portland Cement, which has remained the dominant cement used in concrete production.

*The first Cement manufactured in the United States was produced in 1871 by David Saylor of Coplay, Pennsylvania.

What is Cement ?

*The word cement has come from the Roman word ‘Opus Caementicium’.

*Cement is the general term given to the powdered materials which initially have plastic flow when mixed with water or other liquid.

*A Cement is binder, a substance used in construction that sets, hardens & can bind other materials together.Cement is hydraulic material which develops strength when

it reacts with water.

*What is cement?

It is inorganic material which consists of oxides of calcium,silicon,iron,aluminum.*Phases in Cement

* C3 S

* C2 S

*C3 A

* C4 AF

C - CaO , S - SiO2 , A - Al2O3 , F - Fe2O3

*Composition of Cement

Lime Calcium Oxide (CaO) = 60-65% (63%) Silica (SiO2) = 20-25% (22%) Aluminum Oxide = 4-8% (6%) Iron Oxide = 2-4 % (3%) Magnesium Oxide = 1-3 % Gypsum = 1-4%

Cementation Reaction*Cement are classified as hydraulic and nonhydraulic. *Hydraulic cement sets and harden under water. *Nonhydraulic cement cannot hard under water and require

air for hardening*When water is added to the cement, a hydration reaction

occurs, producing a solid gel that forms the aggregate particles.

How Cementation Reaction Occurs ?Portland cement when mixed with water undergoes the process of Setting & Hardening

The initial stiffening or setting of PC pastes appears to be the result of the rapid hydration taking place on the surface of the cement particles. This rapid initial setting is controlled by the presence of calcium sulfate and for this reason a small proportion of gypsum is interground with cement clinker to control the rate of initial setting. Following this the principal reaction is the formation of single calcium silicate hydrate(C-S-H) from the various anhydrous calcium silicates present in the cement particles.

* C3S + 3H --> C-S-H + 2C-H

rigid gel

* C2S + 2H --> C-S-H + C-H

rigid gel

* C3A , C4AF have less hydraulic properties but useful for liquid formation in kiln.

C - CaO , H - H2O

Cement Industries In Bangladesh*In Bangladesh there are two types of cement

companies one local companies and one is multinational companies.

Local Companies Market ShareShah Cement 14.2%Heidelberg Cement 9.3%Meghna Cement 7.4%Seven Circle BD Ltd. 6.9%Unique Cement 6.1%MI Cement (Crown) 5.9%

Local companies Market share

Premier cement 4.5%

Akij cement 4.2%

Royal cement 4.0%

Mongla cement (SKS)- elephant

3.9%

MTC cement(Tiger) 3.8%

Total 70.2

Multinational companies

Market share

Heidelberg 9.31%

Lafarge Surma 7.67%

Holcim 7.45%

*Types & ApplicationsTypes of Cement Purposes

Portland Cement Used in the production of concrete,in mortars for plasters & screeds.

Rapid Hardening Cement

Attains high strength in early days, it is used in concrete.

Quick Setting Cement Used in works is to be completed in very short period & concreting in static & running water.

Low Heat Cement Used in massive concrete construction like gravity dams.

Sulphates Resisting Cement

Used in construction exposed to severe sulphate action by water & soil in places like canals linings,culverts,retaining walls,siphons etc.

Types Purposes

White Cement It is more costly & is used for architectural purposes such as pre-cast curtain wall & facing panels, terrazzo surface etc.

Coloured Cement They are widely used for decorative works in floors.

Pozzolanic Cement Used in marine structure, sewage works.Air Entraining Cement

Specially suited to improve the workability with smaller water cement ratio and to improve frost resistance of concrete.

*Process Overview

Mining &Crushing

Raw MillGrinding

Raw MealHomogenization

Pyro ProcessingClinkerization

FinalGrindingPackaging

Crushed Limestone

Additives i.e.Iron ore orClay

Coal AshFrom Coal Fired

Fine Raw Meal(120)Res. < 3%

Lt. wt 1200-1350 Clinker

1) Gypsum2) Flyash 3) Pozzolona 4) Slag

1) OPC2) PPC 3) Slag Cement

Blaine 300-350 m2/kgOR(45) Res. <16% Cement

*Process Overview grindingLimestone+Clay+Sand+ Additives ------------

> Clinker heating

Clinker + Gypsum + Additives ------------> Cement

grinding

Different Type of Process

*Wet Process*Raw feed fed to kiln contains 30-40% water by

weight*Semi Wet Process / Semi Dry Process*Raw feed, prepared by either the wet or dry

methods according to the nature of the raw materials is formed into pellets or modules, which are fed into the kiln by way of a grate preheater in which the moving bed of nodulized material is dried and brought upto calcining temperature by heat from kiln.

*Dry Process*Raw Material fed to kiln contains 2-4% water by

weight

*Differences of ProcessesOn basis of raw material processing, cement maufacturing

process are two types. They are- dry process and wet process.

* Wet process is used only in chatak Cement Co.Ltd. and other industries use dry process.

*Process Description*Mining*First step in Cement Production*Drilling is used to drill deep holes in the soil*Blasting is done with the help of drilled holes & explosives*Blasted Limestone is excavated with excavator*Unearthed Limestone is transported to Crusher

Process Description*Raw Meal Preparation*Crushing Limestone from Mines*Limestone from Quarry requires coarse size reduction as

it is in the form of big boulders.*Crushers are used in two or three steps for coarse size

reduction.*Types :Jaw Crusher , Hammer Crusher , Impact crusher.

*Pre-homogenization of Limestone*Limestone ,excavated from different benches, has

different chemical composition.Hence homogenization is needed.*In this Crushed limestone is stacked onto stock pile in

such a way that inherent CaCO3 Inconsistency is evened out.

*Process Description

*Raw Meal Grinding*Pre-homogenized Raw Meal in addition with

additives ,e.g. sandstone, iron oxides, clay etc., is ground in Raw Mill.*Types : VRM , Closed Circuit Ball Mill *Hot air from Preheater is used for removing

moisture in Raw Meal.*Homogenization of powdered Raw Meal is done

in blending silo so that Chemical properties of Raw Meal gets equalized w.r.t. time.

*Process Description*Pyroprocessing*The homogenous raw meal is preheated in Preheater.*The material is then calcined upto 90% in Calciner.*The Calicined raw meal is sintered into clinker in a rotary Kiln.*Fuel (Coal , Oil) is fired into Kiln to sinter the raw meal.*Red hot Clinker is cooled in cooler.*The cooled clinker is crushed in Clinker breaker & stored in silo or Gantry for finished grinding.

*Process Description*Cooling Unit*The objectives of cooler are to recuperate as much heat as

possible from clinker to improve heat economy and to make clinker acceptable to subsequent conveying devices.

*At the end of the Kiln, the clinker possesses temperature around

12000C.

*The cooler contains eleven cooling fans which blow ambient air in both axial and radial directions to cool down the red hot clinker to about 1000C.

*

Generated hot air is re-cycled in the Kiln and Pre-heater as secondary air.

A Cooler Crusher works to crush large size clinkers. The clinker is then stored in a closed vessel called Clinker Silo.

*Process Description*Crushed Clinker is mixed with gypsum & fed into Cement Mill for fine size reduction.*Gypsum is added to control setting time of cement.*Circuit Types : Open circuit Ball Mill , Closed circuit Ball Mill , Roller Press with Ball Mill,VRM with Ball Mill

*Depending on final Cement requirements Flyash or Slag is added along with Crushed Clinker.

* Figure: Cement mill section

* REACTION ZONES

Evaporation zone: 70 to 110 °C - Free water is evaporated.Calcining zone: 400 to 600 °C - clay-like minerals are decomposed into their constituent oxides 650 to 900 °C - calcium carbonate reacts with SiO2 to form belite(Ca2SiO4)

* REACTION ZONES

Intermediate compound formation zone: 900 to 1050 °C - the remaining calcium carbonate decomposes to calcium oxide and CO2 and forms intermediate compounds Clinker formation zone: 1300 to 1450 °C - partial (20–30%) melting takes place and clinker formation completes

Kiln Reactions

1. At 9000C and above, the evolution of CO2 from the decomposition of limestone occurs. The reaction is endothermic.

CaCO3 CaO + CO2

2. Main reaction between lime and clay takes place between 9000C-12000C and 2CaO.SiO2 is formed. The reaction is exothermic.

2CaO + SiO2 2CaO.SiO2

3. Formation of 3CaO.Al2O3 occurs at 1200-13000C. The reaction is exothermic.

3CaO + Al2O3 3CaO.Al2O3

4. The charge starts melting at 12600c. The reaction is endothermic.

5. Clinker formation between 1260-15000c with lime.

* Figure: Rotary kiln

*Material & Energy Balance

*Basis:1. Clinker production rate 3600 TPD (TPD = ton per day)2. Raw meal factor = 1.543. Clinker factor = 0.754. Air moisture = 1%5. Raw material factor = 1.52 kg/kg clinker6. Kiln feed = 1.66 kg/kg clinker7. Heat consumption = 786 kcal/kg clinker8. Calorific value of natural gas = 9600 kcal/ Nm3

*NATURAL GAS CONSUMPTION

REACTION* CH4 + 2O2 CO2 + 2H2O*C2H6 + 3.5 O2 2CO2 + 3H2O*C3H8 + 5O2 3CO2 + 4H2O*C4H10 + 6.5 O2 4CO2 + 5H2O*C5H12 + 8O2 5CO2 + 6H2O

*MATERIAL & ENERGY BALANCE

*Natural gas consumption is 0.082 Nm3 per kg clinker*2.0325 Nm3 O2 required to burn 1 Nm3 of

Natural gas*9.77 Nm3 Air required to burn 1 Nm3 of Natural

gas*1.045 Nm3 CO2 produced from 1 Nm3 of Natural

gas*2.005 Nm3 H2O produced from 1 Nm3 of Natural

gas *N2 found 7.75 Nm3 from 1 Nm3 of Natural gas

when burn.

CO2 produced from 0.0792 Nm3 of Natural gas = 0.08569 Nm3 CO2/ kg clinker

CO2 produced from feed= 0.275 Nm3 CO2/ kg clinker

Total CO2 produced = (0.08569+0.275) =0.36069 Nm3 CO2/kg clinker

H2O produced = 0.16441 Nm3 H2O/kg clinker

Total N2 produced = 6.102 Nm3 N2/kg clinker

Total produced gas = (0.3601+6.102+ 0.16441) = 6.6262 Nm3 gas / kg clinker

Composition of gases in the preheater outlet ( dry basis): CO2 = 5.57% N2 = 94.43%*Flue gas composition in kiln department (dry basis):

Name of the components

Composition (%)

CO2 5.57%N2 94.43%O2 0.0 %

*INDIVIDUAL EQUIPMENT DESIGN

*Basis:*Clinker production rate = 3600 TPD*Cement production rate = 105 ton/hour*VRM grinding rate: 81% limestone, 16%

clay, 2.5% sand, 0.5% iron ore*Clinker/ Cement factor =0.8* Raw meal factor =1.52 kg/ kg clinker , 5%

moistureComponent % quantity

Clinker 72%

Limestone 24.5%

Gypsum 3.5%

*INDIVIDUAL EQUIPMENT DESIGN

Cement silo design:*Production rate =105 ton/hour*For 5 days storage,*Live capacity = (105*24*5) =12600 ton 13000 ton Clinker silo design:*To produce 105 ton/hour cement clinker needs =75.6

ton/hour*So clinker needs per day = (75.6*24) =1814.4 ton 1850 ton*But clinker produce =3600 ton per day.*Per day clinker stores = (3600-1850) ton= 1750 ton*For 1 month storage, Live capacity = (1750*30) =52500 ton

*INDIVIDUAL EQUIPMENT

DESIGN Raw meal silo design:*Designed to store raw mix of 24 hours in case of emergency*Raw meal factor = 1.52 kg/ kg clinker *To produce clinker 150 ton/ hour, raw meal needs=

= 228 ton raw meal/hour*For 24 hours, Capacity = (24*228)=5472 ton per day 5500 TPD

*INDIVIDUAL EQUIPMENT

DESIGNVertical roller mill design:*As 5% moisture present,*Raw material needs = * =5225 ton per day*VRM running time 20 hours/day*Raw material grinding capacity = =261.25 ton/ hours

*INDIVIDUAL EQUIPMENT

DESIGN Limestone storage design:*In clinker, limestone present at 81%. So limestone needs =

211.6125 ton/hour*To store limestone for 10 days limestone required=

(211.6125*24*10) ton =50787 ton 51000 ton Clay storage design:*In clinker, clay present at 16%, so clay needs =41.8

ton/hour*To store clay for 10 days clay required= (41.8*24*10) ton

=10032 ton10500 ton

*INDIVIDUAL EQUIPMENT

DESIGN Sand storage design:*In clinker, sand present at 2.5%, so sand needs

=6.53125ton/hour*To store sand for 10 days sand required= (6.53125*24*10)

ton =1567.5 ton 1600 tonIron ore storage design:*In clinker, iron present at 0.5%, so iron needs

=1.30625ton/hour*To store iron for 10 days iron required= (1.30625*24*10)

ton= 313.5 ton 320 ton

*RECLAIMING AND HOPPER CAPACITY

Limestone reclaiming capacity for VRM:*The cycle time is 20 hours. We want 16 hours as working

hour.*So the reclaiming capacity = = 264.52 ton 265 ton*So the hopper capacity= (265*16 -211.6125*16) =854.2

ton 855 ton Clay reclaiming and hopper capacity for VRM:*For 10 working hours,*Reclaiming capacity = (41.8*20)/10= 83.6 ton 84 ton*Hopper capacity =(84*10 – 41.8*10) = 422 ton 425 ton

*RECLAIMING AND HOPPER CAPACITY

Sand reclaiming and hopper capacity for VRM:*For 10 working hours,*Reclaiming capacity= (6.53125*20)/10 =13.0625 ton 14

ton*Hopper capacity =(14*10 – 6.53125*10) = 74.69 ton 75 ton Iron ore reclaiming and hopper capacity for VRM:*For 10 working hour,*Reclaiming capacity = (1.30625*20)/10 =2.6125 tons 3

tons*Hopper capacity = (3*10 – 1.30625 *10) =16.94 tons 17

tons

*RECLAIMING AND HOPPER CAPACITY

For Cement millReclaiming and hopper capacity for Clinker :*For 10 working hours,*Reclaiming capacity =(75.6*24)/10 =182 tons/ hour*Hopper capacity = (182 *10 – 75.6*10) =1064 tonsReclaiming and hopper capacity for Gypsum *For 10 working hours,*Reclaiming capacity =(3.5*24)/10 =8.4 tons/ hour 9 tons/hour*Hopper capacity = (9*10 – 3.5*10) =55 tonsReclaiming and hopper capacity for Limestone:*Reclaiming capacity = (24.5*24)/10 = 58.8 tons 60 tons*Hopper capacity = (60*10 – 24.5*10) = 355 tons

CEMENT PLANT LAYOUT

00. Limestone Quarry and Crushing plant

01. Limestone Stockpile

02. Additives Hopper

03. Additives Storage

04. Raw Mill Building

05. Blending and Storage Silo

06. Preheater

07. Gas Conditioning Tower and ESP

08. Kiln

CEMENT PLANT LAYOUT