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VOCATIONAL TRAINING REPORT

02-05-2016 to 02-06-2016

GUIDED BY: SUBMITTED BY:

Mr. ROHAN SHOME SUDHANSHU SHEKHAR (Dy. Mgr./Mech.) KIIT UNIVERSITY,BBSR

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CONTENTS

TOPIC PAGE NO.

1 2 3 4 5 6 7 8

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10

11

12

13

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15

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ACKNOWLEDGEMENT CERTIFICATE ABSTRACT INTRODUCTION CEMENT MANUFACTURING PROCESS MANUFACTURING OF KONARK CEMENT AT OCL- A BIRD'S EYE VEIW Raw material mining/procurement

Lanjiberna Quarry

Raw material handling Crusher Wagon trippler

Stacker & Reclaimer Raw mill grinding

Vertical Roller Mill Electrostatic Precipitator(ESP) Gas Conditioning tower Raw Mill Blending Silo

Coal Grinding Coal Crusher

Coal Mill Pyro-processing / Clinkerisaton

Preheater / Pyroclone Dry Process Rotary kiln

Grate Cooler Cement Formation

Overhead Crane

Hopper Cement Ball Mill

Cement Vertical Rolling Mill (CVRM) Bag Filter

Packing & Dispatching Packing House

Roto Packer ENVIORNMENTAL PROTECTION ACTIVITES

CONCLUSION

3 4 5 6 8

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ACKNOWLEDGEMENT

I, Sudhanshu shekhar of KIIT UNIVERSITY had a great time

working under the supervision of the members of OCL. I would like

to thanks all the members who guided me throughout my training

period and share their knowledge about the production process and

instruments used in cement factory. My sincere thanks to Mr. Debi

Prassad Das of OCL India Ltd. for his encouragement and valuable

suggestion during period of my training and report preparation. I

would also like to thanks Mr. Rohan shome and Mr. P.K.Rout

(Manager, HRD) for their extreme help and guidance under which

training was completed easily.

No word would suffice to express my regard and gratitude to

all the members of line-2 department Mr. dillip panda sir, Mr. bakshi

sir, Mr. rohan sir and also the attainder of various section of line 2

department, Mr. krishna, Mr. amit kumar for their constant

encouragement and valuable timing throughout the course of our

training.

I express my gratitude to all the mentors for their valuable

suggestion and guidance, without their cooperation this report is

incomplete.

-Sudhanshu shekhar

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CERTIFICATE

This is to certify that the vocational training report on OCL

India ltd. is submitted by Sudhanshu shekhar of KIIT

UNIVERSITY, Bhubaneswar towards partial fulfillment for the

award of the degree of bachelor of technology in the branch of

Mechanical Engineering is a bona fide record of the work done in

oue supervision and guidance.

It is a faithful record of bona fide training report cared by

Sudhanshu Shekhar under our supervision & guidance. It is further

certified that no part of this report has been submitted to any other

university or institute for award of any other.

.......................... ........................

Mr. P. Murlimohan Mr. D. P. Das

(A.E.D./ Engg.) (Mgr./ Mech)

(Engg. Head)

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ABSTRACT OCL India Ltd. better known as OCL is a public limited company located

at Rajgangpur, a small village in the district of Sundargarh, Orissa in India. It was established in the year 1951, having a single wet process Kiln with a capacity of 4 Lakh tons of cement per annum. Subsequently it was converted into a five stage pre-heater with pyroclone and dry process Kiln. The present capacity is 2.9 million ton per annum. Its product KONARK brand cement enjoys over the years a premium brand name and has been the market leader in the state of Orissa.

Though initially the cement unit was established for catering cement for the construction of HIRAKUD dam but subsequently hardly there is any prestigious construction of national and or international repute in Eastern India where the KONARK cement contribution is not there.

The company produces as many as seven varieties of cement in its single unit at Rajgangpur through its state of the art technology having most modern computerized control and monitoring system right from raw mix preparation up to finished cement grinding, packing and dispatch system.

Fig - i

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INTRODUCTION OCL’s Cement plant is one of the most modern dry process cement plants in India. It was founded by Late Sri Jaidayal Dalmia. ’Konark’ brand cement manufactured by OCL is the market leader in the state of Odisha and has emerged as a brand synonym of premium quality cement.. It has got three units at Rajgangpur presently:

1. Cement Works 2. Refractory Works

CEMENT WORKS: Cement Division was established in 1949. Its initial capacity was 4 lakh tons per annum having wet process at that time. It was expanded in 1988 to 7 lakh tons per annum following dry process & computerized central control system. It was again expanded in March’1997 to 10 lakh tons per annum, employing a Vertical Roller Mill (VRM),a giant clinker grinding unit. Clinkerisation capacity 9.0 lakh ton per annum had been achieved by taking preprocess modification and installing twin low pressure pre-heater in year 2004. Installed capacity of 2 million ton of cement production had been achieved in the year 2005 after completion of installation of installation of 3rd CVRM. Annual turnover of cement unit – 400 crores (approx.). It has got ISO -9002 Product certification for oil well cement had been from API in year 2004.

Types of Cement Manufactured at Orissa Cement OCL is presently manufacturing the following under the brand name of KONARK CEMENT. Ordinary Portland Cement (OPC)-33 Grade, 43 Grade,53

Grade[Gypsum-4% & rest Clinker with Fineness (Blains) 325 m2/Kg] Portland Slag Cement (PSC)[Gypsum-4%,Slag-30 to 40% & rest is Clinker

with fineness(Blains) 325 m2/Kg] Special Cement (IRST-40) [Gypsum-4%, Clinker-96% with Fineness

(Blains)-370 m2/kg Sulphate Resisting Portland Cement (SRPC) [same as PSC except that

variation in some chemical composition] Portland Pozzolona Cement (PPC) [Gypsum-4%,Fly ash - 25% & rest is

Clinker with Fineness(Blains) 325 m2/Kg] Oil well cement -Class -G-HSR

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Fig - ii

Masonary Cement

(IS-3466-1988)

53-S Grade OPC

(IS: 12269-1987)

Portland Pozzolana Cement

(IS: 1489 Part-1 – 1991)

Portland Slag Cement

(IS-455:1989)

Sulphate Resisting Portland

cement (IS-12330:1988)

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CEMENT MANUFCTURING PROCESS CEMENT:

Cement is a substances applied to the surface of solid body to make them where firmly or more specifically a powdered substances which made plastic with water in used in a soft and pasty state (which hardens on drying) to bind together bricks, stone etc. in binding Portland cement is a calcined material composing lime and silicate which mixed with sand & stone and upon hydration form a plastic material which sets & hardens to a rock like material called CONCRETE. For cement, clinker is the main product of the rotary kiln (furnace) & is hard, light black in color. After grinding clinker (95%) with gypsum (5%), we get ORDINARY PORTLAND CEMENT (OPC).

a) 45% slag + 5% gypsum + 50% clinker = PSC Cement(PORTLAND SLAG CEMENT)

b) 25% fly ash + 5% gypsum +70% clinker = PPC Cement(PORTLAND POZZOLANA CEMENT)

Slag is the waste product of steel plant i.e. from blast furnace and fly ash is the waste product of thermal power plant. These two slags & fly ash are materials which are not they cementation but are latently hydraulic content same CaO. The central govt. has given order to all the cement plant to use the waste like slag & fly ash in cement industry compulsorily. Therefore, they are saving clinker & producing more cement to the market. Now from cement concrete roads are manufactured instead of pitch road which are environment friendly and gives long life with good quality finishing. The most expensive component when producing cement is fuel (Coal) & power (Electricity). So, most of the plant are taking foreign plants are using latest technology with good quality latest foreign equipments for producing cement. Indian coal is relatively of poor quality with higher ash content i.e. low calorific value but easily available in large quantity.

Because of the high temp. Existing a kiln (950oC to 1450oC) and pre

heater tower (340oC to 900oC) and cooler (1250oC to 200oC) during clinker

manufacturing system to protect the steel shell of the kiln, preheater & cooler

with refractory bricks & castable inside the system with good quality. OCL is

using their OCL refractory bricks & castable to protect the steel shell. Most of

the cement plants are also taking OCL refractory bricks & castable.

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For manufacturing cement the main raw material is LIMESTONE (95%).

The clay is suitable for low silica & alumina. In raw mix cinder used for

alternative to clay, which is burnt coal (80%).

By grinding limestone with additive like clay cinder, morrum in a vertical

roller mill to convert in dry powder form is called raw mill or raw mix for

rotary kiln. It always keeps in Big Silos or Tank. In OCL line-2, one raw mix

keeping silo are present and its capacity is 5000 tons having 45mts height. In

every hour the main raw mix grinding material from vertical roller mill

collected for laboratory testing in XRF for better result to maintain quality raw

mix. The capacity of the vertical roller mill of limestone grinding of line-2 is

450 tones per hour.

The limestone comes from Lanjiberna mines after blasting the

limestone during night duty & it converts into 75mm to 100mm size crushing

it into the limestone crusher. Then it is carried to OCL by conveyor belt.

The limestone comes to OCL inside and makes a big stock pile for

grinding in vertical roller mill. The capacity of one stock pile is 15000 tones.

We have two stock piles for keeping lime stone. Then, after reclaiming the

limestone through reclaimer it goes to limestone hopper through belt

conveyor.

In VRM section of limestone grinding, we have four hoppers: a) One for keeping limestone b) Second one for keeping Clay or Cinder c) Third one for keeping Morrum (Fe2O3) d) Fourth one for keeping Sweetener which is nothing but high grade

limestone only high CaO content

Coal is the prime input for firing or burning the raw mix inside the kiln and pre heater for making clinker. Coal fishes into a kiln and pyroclone as dry powder only having good fineness. In OCL line-2 there is only one vertical roller mill for grinding coal. Inside the mill there are three hydraulic rollers for grinding. The capacity of the coal vertical roller mill is to produce 30 tons per hour of fine coal. The coal generally comes from Gopalpur, Korba,Meghalaya, and South Africa etc. as raw coal. Coal is composed of carbon, hydrogen, oxygen, nitrogen, and sulphur with very small amount of also other elements. The composition is 80%-90% Carbon, 4%-5% hydrogen, 5%-10% oxygen, 1.5%-2% nitrogen and 1% of organic Sulphur. The calorific value of the coal is the most important and it

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depends on the content of volatiles, ash and the moisture. The good quality coal having high calorific value and low ash content. From our raw mix or raw mill silo the dusty material gone to the preheating tower (nearly about 135mt height) through bucket elevator at the top floor. The pre heater tower consists of cyclones having five stages hollow inside to give the raw mix and hot gas in cyclonic motion for proper calcinations. The material (raw mix) reaches within 30sec from pre heater top to the kiln furnace inside (inlet area) During that 30sec period, near about 90-95% calcinations should be done at pre heater which is called flameless firing and 60% coal used(fine coal) at the pre heater, rest 10% calcinations and burning of the raw mix done inside the rotary kiln(furnace) have firing from kiln inside from the kiln outlet platform area with fine coal 40%.

Pre heater cyclones are dust separation units, which are separated the

heated raw mix from the hot gases in the gas duct. Heat transfer takes place

in the pre heater cyclones between the gases and the raw mix at user duct

point. The gases leave the cyclones through the top and material spiral down

to the kiln. One big pre heater fan runs for doing this calcinations job well. At

the top the gas temps. Remain 320oC to 380oC and at bottom of preheater

means entering to the kiln remain 900oC to 990oC. The raw mix color changes

from ash color to milky tea color that enters to the kiln.

The chemical reaction of the raw mix starts at 500oC from preheater to

1450oC inside the kiln. From kiln end point the raw mix enters into the rotary

kiln (furnace) at 990oC and goes on rotating to come faster. Evolution of CO2

from Calcium Carbonate started from 815oC. Then from inside the kiln the

temp. Gradually increases in each step by producing C2S, C3S, C3A, C4AFetc. At

near about 1250oC the hot raw mix powder slowly melts to liquid state. Then

the liquid raw mix temp. Fall from 1400oC to 1200oC by converting it to solid

red hot clinker balls. So, max. temp. of the kiln is on the 1/3rd of the total kiln

length. The total kiln length of line-1 is 56mt and diameter is 3.8mt.

The red hot clinker granules fall on the cooler having perforated plates.

The max. Air given by a no. of fans (nine fans) from the bottom of the plate to

cool down the clinker from 1250oC to 150oC only. The steel plate’s move like

shaking conveyors very slowly and it take 25-30 min inside the cooler for

proper cooling. Then the cooled clinker became light black in color and pass

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through the clinker crusher to become small size for storing in clinker silo. But

in kiln clinker produced within 20 – 25minutes only.

Every hour the cool small clinker collects for x-ray laboratory testing to

get the C3S strength and all other detail result for taking further action. This is

a continuous process for 24hrs. In line-2 of OCL (new plant) the clinker

production capacity is 4000 tons per day in 24hrs.

Both line-1 and line-2 plant have been designed by KHD Germany and

its technology is the best in world. limestone grinding VRM are from Germany.

For storing the final product cement there are 17 silos (Big Tank) and

two other silos also having total capacity of 36000 tons cement.

The cement packing done through rotor packer. Automatically in each

bag having 50 kg capacities. The transporting of cement bags done through

the trucks and railway wagons to outside.

The Central Control Room (CCR) is the heart of the cement plant and

from CCR all the units are operating by the expert operators regularly.

Through the computerizing modern technology system, through monitors all

the dates are coming continuously. The start, stop, increases, decreases etc

i.e. everything’s controls only from that control room through the keyboards.

In OCL Cement Plant, there are a few bag filters, ESP (Electro Static

Precipitators) for controlling the dust emission for keeping the environment

good and greenery. Since, the 60 years OCL has been producing cement in

India at Rajgangpur which is marketing at the name of “KONARK BRAND

CEMENT”

Use and purpose of cement:

1. The first and foremost use of cement is to act as main ingredient in

concrete. it is used for walls, roofs, bridges, concrete roads, flooring,

etc.

2. Used for railway sleepers.

3. Used in foundations

4. Used for pillars, piers and columns.

5. Oil well cement is used for oil well dugs, water tank .

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MANUFACTURING OF KONARK CEMENT AT OCL

A BIRD’S EYE VIEW

Fig – iii

The manufacturing process consists of the following stages: -

1) Raw material mining /procurement. 2) Raw material handling/proportioning. 3) Raw material grinding. 4) Coal grinding. 5) Pyro processing/Clinkerisation. 6) Cement formation. 7) Packing and dispatch

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Raw materials mining / procurement Main constituent Lime stone is produced form its captive mines at Lanjiberna Quarry, which is 10 Km from the cement works. Other raw materials i.e. Clay, Laterite, Hard Morrum are procured from outside sources. Blast furnace Slag is procured from Steel Plants at Rourkela, Vizag, Bhilai, etc. Fly ash is procured from the power plants at Rourkela Steel Plant, INDAL Sambalpur and other nearby thermal power plants.

Raw material mixtures for cement manufacturing should have following constituents by percentage:

CONTENTS RANGE IN %BY WEIGHT AVERAGE IN % BY WEIGHT

CaO 60-69 65

SiO2 18-24 21

Al2O3 4-8 6

Fe2O3 1-8 3

MgO Less than 5 2

K2O Less than 2 1

Na2O Less than 2 1

SO3 Less than 3 1 TABLE - i

LANJIBERNA QUARRY

This is the captive mines of OCL .It is about 10 Km from the works. It is an open cast mines. After quarrying operation, the limestone boulders are crushed to a nominal size of 75 mm by an impact type crusher. Thereafter, the crushed limestone are transported up to JAMPALI exchange yard in 10 ton box type wagon pulled by a diesel locomotive from where electric locomotive carry them to RAJGANGPUR cement works.

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Raw material handling / proportioning CRUSHER

INTRODUCTION

Previously, there were two secondary Crusher units (Hammer Mill) which have been already taken out. Now, function of the section is to unload

limestone procured onto hoppers and transport up to stacker/reclaimer unit.

MAIN EQUIPMENT: 1. WINCHES

Unidirectional type - 2 No’s

Reversible type - 2 No’s FUNCTION:-For shunting loaded wagons up to tipplers

2. WAGON TIPPLERS -2 No’s • Tippler No.1 —90 tph • Tippler No.2 —180 tph FUNCTION: To unload Limestone from wagon onto existing hoppers by tilting.

Fig - v

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WAGON TIPPLER

A wagon tippler is a compact machine and discharges limestone from open top rail wagon by inverting the wagons over a track side hopper. It is driven through two numbers of Pinions connected to the gear by pinion shaft

and jack shaft, maximum angle of rotation is 155 degree.

In line-1 it has two wagon tipplers supplied with winches which shunt the wagons to the tipplers. The wagons are unloaded to the limestone hopper. Then the lime stones are carried by laminated conveyer belt which at last is

connected to stacker belt.

STACKER & RECLAIMER INTRODUCTION:

The intermediate storage of raw materials between Quarry & Raw Mill is required to form the stock pile from where a steady supply of materials for processing in the cement works is maintained. In addition, it has, in recent years, become increasingly important for the purpose of pre-blending or pre-homogenizing of the crushed limestone for process. By stacker limestone procured in different trips having varying constituent is stacked longitudinally layer by layer spread over the entire width .At the time of reclaiming transversely, all the layers from a particular section goes together thereby ensuring blending.

TECHNICAL SPECIFICATIONS: Type of stock pile :Chevron type

Type of stacker unit :Boom type Type of reclaimer unit : Scrapper type with Harrow attachment

Stacker feed rate :600 tph

Reclaimer capacity :500 tph

Storage capacity :15,000 MT x2 No’s

Blending efficiency :1:10 Size of Stock pile :98m (L) x 25m (W) x 9.8m (H).

Raw material grinding Reducing the raw meal to a fine powder form conventionally called raw meal is necessary in order to produce a homogenous mixture which will be quickly converted in the kiln into a homogenous clinker containing no free lime.

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MAIN EQUIPMENT:

Vertical Roller Mill (VRM)

Electrostatic Precipitator (ESP)

Gas Conditioning Tower

Raw Meal Blending Silo

VERTICAL ROLLER MILL (V.R.M)

GENERAL INTRODUCTION:

The LOESCHE mill belongs to the species of roller mills. The mill is designed with three rollers. Each roller together with the rocker arm, in which it is rigidly clamped, the pedestal in which the rocker arm is mounted and the hydro pneumatic spring system, represents a power unit. This power unit is a building block or module which can be arranged two fold, threefold or four fold around the grinding table.

VRM:LM 46.4.2 LM– LOESCHE MILL, 46– TABLE DIA (46 DECIMETER) 4– NO. OF ROLLERS 2– ROLLER DIA (1 METER)

METHOD OF OPERATION:

The rotation of the grinding table distributes the grinding stock uniformly over the horizontally arranged grinding plate. The tapered grinding rollers draw the grinding stock in and crush it. When the grinding rollers come in contact with the grinding stock, the piston of the hydraulic cylinder is lifted during crushing process via rocker arm and the connecting rods and the fluid of the upper chamber of the cylinder is displaced into gas filled hydraulic accumulator. This compresses the gas which functions as a spring. Centrifugal forces throw the crushed material from the grinding table into the upper portion of the Louvre ring which surrounds the grinding table. The stream of the hot gases being sucked from the grinding mill blower moves the crush material upwards to the classifier through the mill body. The intimate contact of the grit with the hot gas evaporates the moisture in the grinding stock spontaneously. The residual moisture content will be approximately 1%.

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Material which has not been crushed to the specified size is rejected by the classifier. The rejected material falls in the internal grit return for recycling.

Fig - vii

SPECIFICATION:

1. MILL TYPE :LOESCHE Mill LM 46.4.2 2. MILL OUTPUT : 450 TPH 3. FEED SIZE : (0-75) mm. 4. RAW MILL FINENESS : 20% residue on DIN 0.09 5. RAW MILL MOISTURE : Max 2% H2O. 6. MILL GEAR BOX : It consists of special design as bevel

Helical gear with horizontal input shaft and vertical output flange.

(A) TYPE : STK-170H (B)MAKE :RENK

7. CLASSIFIER :FLENDER GERMANY (A) POWER :170KW (B) RPM : 120

8. WATER INJECTION UNIT :Capacity 8 m3/hr at a pressure of16 bar 9. FAN DETAIL :Capacity-383000 m3/hr

(A) TEMPERATURE :100 degree centigrade (B) SPEED :980 rpm (C) POWER :1900kw

10.MAIN MOTOR

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(A) POWER :1120 KW

(B) RPM :750

(C) FR. No. : IRS 7567-8P 11.CLASSIFIER : LSKS-52

(A) POWER : 75 KW (B) RPM :94

12. CLASSIFIER MOTOR:

(A) POWER :170 KW

(B) RPM :450 to 1000

(C) TORQUE :600 N.M 13. MILL FAN MOTOR

(A) POWER :1900KW (B) RPM :600 to 980 (C) FREQUENCY :50Hz

14.TABLE (A) DIAMETER : 4.6m (B) RPM : 40

15.DAMRING HEIGHT : 80mm 16.ROLLER DIAMETER :2m 17.GRINDING PRESSURE:(70-90) Bar

LUBRICATION USED IN V.R.M

1. MAIN GEAR BOX DRIVE : SMSP-320 2. HYDRAULIC PANNEL : S.S-68 3. ROLLER PANNEL : SMSP-460 4. CLASSIFIER GEAR BOX : MOBILE XMP-320 5. TRIPPLE FEED GATE

HYDRAULIC OIL : 361 LP1 6. GREASE USED IN

CLASSIFIER BRG : 361 GP1 7. GREASE USED IN

TRIPPLE FEED GATE BRG : SERVO JEM EP-2 8. GREASE USED IN

ROCKER ARM BRG : SERVO JEM EP-2

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Electrostatic Precipitator

The Electrostatic Precipitator applies the effects of gas ionization in a strong electric field. The plates on which the dust is collected are grounded and high voltage wires are hung between the plates. The wires, connected to a high voltage power supply, create an electrostatic field between the plates. The gases passing through are ionized and impart a negative charge to the dust particles. The negatively charged dust particles are attracted to the positively charged plate on which they are precipitated and lose their charge. The plates are rapped and the particles fall into collection hoppers for removal. Some of the dust particles become positively charged and are attracted to the discharge wires which, therefore must also be rapped.

TABLE–ii

Fig - viii

ESP(Location) TYPE FAN DRIVE(kW FAN RPM NO’S.

Raw Meal VRM Horizontal 2100 0 – 1000 1

Pre-Coal ESP Horizontal 75 975 1

Coal ESP Vertical 240 735 1

Mill House ESP Horizontal

200(I & II) 0-1000 1 315 (III & IV) 0-1000 1

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Gas Conditioning Tower (GCT)

In order to dry up moisture present in the raw meal VRM,some exhaust gas from Preheater is directed to it(VRM).But this gas sucked from Preheater by preheater fan has got temperature of about 300-3500C whereas VRM inlet temperature should be 150-200o C.So, in order to maintain this temperature, a Gas Conditioning Tower is arranged in between. The function of the GCT is to reduce the high temperature of hot gas to required temperature i.e. 150-2000 C by spraying water whereby water is evaporated with the heat of gas and the gas temperature is reduced while the dew point temperature is increased. Inlet Temp -3800 C & Outlet Temp.-120±100 C.

Fig - ix

Raw Meal Blending Silo

It is the intermediate storage device which can store powdered raw meal from VRM (Raw) which is fed to the kiln later on. Raw meal VRM output is 150 to 160 TPH, whereas preheater intake is 120 TPH. So, if raw meal from VRM will be continuously fed to preheater directly, then it will arise a problem of overloading due to the difference in output of VRM and input of preheater. Properly blending and necessary quality correction in raw meal is also done in these silos. There are one raw meal blending silo in line 1 plant.

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SPECIFICATION: Capacity of silos : 15000 Ton Height of silo : 75 m Equivalent height : 45 m Dia. of Silo : 20.8 m

Coal grinding Pulverized coal is used as the fuel for firing in kiln as well as preheater, which is finally converted into ash and absorbed in the clinker processed. At OCL, graded coal is procured from outside sources like MCL and stored in a coal pit at works. A legged crane feeds this coal to a hammer crusher, which crushes these lumps to a definite size i.e. less than 25mm. This crushed coal is carried to the grinding unit, a vertical roller mill which grinds it to pulverized form of fineness 90 micron & 212 micron. Then ground coal is stored in four storage bin & transported to kiln by pneumatically conveying system for firing purpose.

MAIN EQUIPMENT:

Coal crusher

Coal mill

COAL CRUSHER

This is nothing but a single rotor hammer mill, which is used for crushing coal from 200 mm to less than 25 mm size. Main feature of the crusher is the rotor which carries a series of pivoted hammers. When the rotor is running ,the centrifugal forces cause the hammers to point radically

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outwards in the upper crushing chamber, the feed material is subjected to a combination of impact and percussive action by the hammers and by repeated collision with the breaker plate, together with " autogenously" action by coal lamps colliding with one another. Output product size is controlled by adjusting the gap between the hammers & breaker plate.

TECHNICAL DATA Type : Hammer Mill Input Size : Less than 200 mm Product Size : Less than 25 mm Capacity : 75 TPH Raw Coal Hopper Capacity : 70 TPH each

COAL MILL This is nothing but a vertical rolling mill. It comprises of three roller on a circular bed like raw mill roller. crushed coal came from line-1 via conveyor belt. That crushed coal feed into coal mill via control gate. There is a magnetic detector placed in the transportation way, if some magnetic material sensed by that detector automatically gate closed and material exhaust via another gate.

TECHNICAL DATA

Type :Vertical rolling mill No. of roller : 3 Power required : 460 kW Capacity : 50 TPH Diameter of roller : 1.8 m diameter of bed : 2.8 m Coal Bin Capacity : 180 ton

Pyro-processing/Clinkerisation

Introduction:

Being extracted from blending silos by bucket elevator/air lift, the homogenous portion of raw meal is fed to the preheater. The preheater is two stream, 5-stage cyclones with ILC (In line Calciner). The kiln feed is feed to the preheater by the bucket elevator. A diverting gate separates the feed to the kiln string & Pyro string. In the preheater tower it gets heated up & by

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the time it comes out of preheater,it is about 90 % calcined. Temperature varies from stage to stage, however it is 8500 C at 5th or final stage. From the cooler outlet hot waste gas supplied through Tertiary Air Duct (TAD) up to preheater cyclone for utilization purpose. About 60 % of total fuel is also fired at Pyroclone of preheater. Then partly calcined raw meal from preheater goes into the dry process rotary kiln. Inside rotary kiln, about 40 % of coal is fired. This causes burning zone temperature about 14000 C .Raw meal which enters into the inlet of kiln is burnt and changed into grayish clinker, which subsequently gets discharged onto clinker cooler. After necessary cooling inside cooler the clinker is carried by Deep Drawn Pan Conveyor into clinker storage hall.

Main Equipment: Preheater

Kiln

Grate Cooler

Clinker crusher

The different equipment fulfill various functions as listed below:

Drying and heating up of the kiln feed takes place in the preheater.

De-carbonation (up to 90%) of the kiln feed takes place in the PYROCLON calciner.

The fuel is ignited and burned out in the combustion zone. The sintering process and the formation of clinker occur inside the

rotary kiln.

The hot clinker is cooled in the clinker cooler. The main process going here is the conversion of calcium carbonate to

calcium oxide.

CaCO3 CaO + CO2

Clinkerisation occurs at temperature between 13500C to 14000C. The time required for the material to pass the rotary kiln is about 20 minutes. The major reactions taking place in the kiln are as follows:

C 3 + A C3A A=AI 2O3

C4A + F C4AF C = CaO & F = Fe2O3

C2 + S C2S S = SiO2

C2S + C C3S

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Fig - xii

PREHEATER / PYROCLONE

With pre calcining almost the entire decarbonation in process is effected in the Calcined, one result of which is that thermal conditions to which the refractory lining in the kiln is exposed become much less severe. This, in turn means that for equal clinker output, the diameter and length of the kiln can be correspondingly reduced. The significant feature is that the calcined is separate from the kiln and that part of the thermal energy required for the clinker manufacturing process is utilized in the calcined and not in the kiln. Unless, otherwise, the length & diameter of the kiln for the purpose would have been unexpectedly large. Besides, the heat contained in the exhaust air from the clinker cooler is also utilized.

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Technical Data: Manufacturer : CROMTON GREAVES Type : 3-Ф AC SCR INDUCTION MOTOR Preheater Fan

Capacity : 6600 m3/min

Drive (kW) : 2200 kW First stage temperature : 3500 C Final Stage temperature : 8500 C RPM : 992

DRY PROCESS ROTARY KILN

The raw meal decarbonated/ calcined in the 5 stage cyclone preheater enters into the SHORT ROTARY KILN at a temperature about 8500 C. The kiln is driven by electric drive (DC shunt motor) & shell is supported by rollers. Also thrust rollers arrangement is provided to compensate the floating of rotary kiln during rotation. 40 % of pulverized coal is fired in the kiln which raises burning zone temperature up to 15000 C, whereby calcined raw meal burns down to grayish granules of clinker and discharged to the grate cooler at outlet. It takes 30 minutes for passing raw meal from inlet up to outlet of kiln for processing.

Technical Data

Type : Short Rotary Kiln Capacity : 4000 TPD Dimension : 4.2 m Dia. x 65 m Length Inclination : 3.5% of kiln length Revolution : 5.2 RPM (Max.) & 0.54 RPM (Min) Temperature of Burning Zone : 14500 C (Approx.) Weight : 400 Ton Power required : 220 kW Power installed : 220 kW Motor types : DC Shunt motor

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Fig - xiii

GRATE COOLER

Clinker manufactured in the rotary kiln is cooled in the Humboldt Grate Cooler to temperature level required for further processing. The Humboldt Wedag Grate Cooler is a reciprocating grate cooler with a continuous grate having inclination of 5%. It basically consists of the housing bottom section with supports & drive for the grate system, the plate covering & the brick lined housing top section. The fire cooling air fans and the clinker crusher for commuting the outsize are connected to the grate cooler. The cooling air is heated up while flowing through the clinker (Cross current flow). A portion of the heated cooling air is routed to the kiln system for reducing the rotary kiln air requirement. Depending on the kiln system and its specific air requirement from the grate cooler air temperature of approximately 7500 C may be reached. A portion of the cooling air is withdrawn from the cooler outlet after passage of the clinker deducted and released into the atmosphere via a stack or recycled to the process. Technical Data

Manufacturer : KHD/ Cimmco Type : Grate Cooler Dimension : 3.5 m (width) x 20.7 m (Length) Power required : 0.85 kWh/ Ton of clinker Power installed : 40 kW/1500 rpm Revolution of Cooler outlet Shaft : 300 RPM Capacity : 3000 TPD with cooling air 3.7 m3/Kg of Clinker Temperature of Clinker at Inlet : 14500 C At Outlet : 650 C

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Cooler Exhaust Fan: Drive Power(kW) :315kW Deducting system : Multi clone Clinker conveyor : Drag chain conveyor & Deep Drawn Pan Conveyer (DDPC) Clinker crusher:

Type - Hammer Mill

Drive : 90 kW

Product size : 0-30 mm

Fig - xiv

CEMENT FORMATION After Clinkerisation seasoned clinker from storage halls fed to the

existing cement mills(4 ball mills) along with Gypsum & other materials like slag etc. by means of overhead crane depending upon type of cement to be manufactured. The plant has got the world’s first vertical roller mill LM 46.2+2 C/S for clinker and slag grinding. The reason for this option is because it is more energy efficient and gives higher output. Three vertical roller mill are installed for grinding cement to which clinker is fed directly from cooler discharge by DDPC (Deep Drawn Pan Conveyor), also having provision for feed

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by crane from storage hall. In Ball mill gypsum, clinker (& slag) are ground together to obtain cement of desired quality. In CVRM, slag and Clinker & Gypsum are ground separately and stored in separate compartments of buffer silo from where OPC or PSC (by inter mixing by means of a paddle mixer) is obtained.

A new generation classifier has been introduced with advanced design at the mill internals for high grinding efficiency.

According to the type of cement required, ingredients are taken and it is done:

1) by mixing all the ingredients together and then grinding, 2) By grinding ingredients individually and then mixing them. Then the finished cement is stored at the silo for despatch.

Recent addition to the capacity addition OCL has commissioned world’s largest vertical roller mill for grinding clinker and slag from LOESCHE, Germany. (LM56.3+3 C/S).

Main Equipment

Over Head Crane

Hopper

Cement Ball Mills(4 No’s)

Cement Vertical Roller Mills (CVRM) Bag Filter

Over Head Gantry Grab Crane

There are two overhead gantry type grab cranes in our clinker storage hall for handling clinker as well as raw materials (morrum, clay, laterite, sweetener etc.) to the respective hoppers, which are subsequently conveyed to respective mills for grinding purpose. In the Over Head Crane, the longitudinal bridge drive is effected by a motor through reduction gear box installed at one side of bridge and transmitting motion or the drive to the other side wheels through a long shaft. The traversing of trolley is attained by another individual motor. Similarly, hoisting of the grab along with material opening as well as closing of the grab are effected by two individual motors respectively.

Technical specification

Span of the crane : 98' Width of bridge : 8' Distance between wheel centre : 20'

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Capacity : 7.5 Tons (Grab wt.: 2 Tons & weight of material lifted: 5.5 Tons)

HOPPER

The hopper capacity of the various hoppers in CVRM are: Gypsum Clinker Slag Wet-Flyash Additive CVRM 1&2 170T 420T 327T 100T 85T CVRM 3 153T 791T 540T 135T 99T

Cement Ball Mills

Cement mills are nothing but horizontal ball mills made of M.S. mill shell inside which Mn. Steel liners are provided to prevent wear & tear caused due to impact & attritional force between material & grinding media during operation. It is driven by a motor through reduction gear box. The ball mill shell has got two chambers. There is an intermediate screen called diaphragm between primary & secondary chambers. Material i.e. Clinker + Gypsum or Clinker + Gypsum + Slag after being ground in first chamber goes to the second chamber through this screen. Then in this chamber, it is ground to the fine powdered form and subsequently goes to the outlet through outer-gate screen, then to the inlet of elevator. For proper control of fineness, mill has been provided with O-separator which controls fineness. Fine material, due to centrifugal action inside separator and suction of ESP Fan goes to ESP and comparatively courser particles come back to cement mills for further grinding. Thereafter, process is cycled.

Technical Data:

Items

MILL NO. 1 2 3 4 Make FLS FLS FLS FLS Type of Drive Central Central Central Central Size [m] 2.6x12 2.9x10.4 2.6x13 2.9x10.4 (Dia x Length) Capacity in TPH

(i) OPC 24 26 24 25 (ii) PSC 22 23 22 23

Mill Speed (RPM) 18.80 18.00 18.80 17.9

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DRIVE

Motor Make Crompton FLS Crompton FLS Parkinson Parkinson KW/HP 900/1300 1040/1400 900/1300 925/1250 RPM 750 750 750 750

Gear Box Make FLS(Symetro) FLS(Symetro) FLS(Symetro) FLS(Symetro) Ratio 40:1 42:1 40:1 42:1

Fig - xv

Cement Vertical Roller Mill (CVRM)

Vertical Roller Mill technology for grinding cement raw materials developed recently is being accepted all over the world because of advantages over the centrifugal ball mill technology. The main reasons for such a wide acceptance of this technology are higher throughputs, savings in specific power consumption, there capability to handle both dry as well as raw materials up to the moisture level of 15-18 % and better dependability and availability.

In constructional feature, Our Cement VRM is the same as raw mill VRM except that Raw VRM has got 3 hydraulic pressed rollers whereas CVRM has

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got 4 such rollers, out of which 2 are slave rollers (non-hydraulic) for leveling the bed of material & 2 master rollers (hydraulic) for grinding purpose.

Fig - xvi

Technical Data

CVRM (1 & 2) MAKE : Loesche, Germany TYPE : LM 46.2+2 C/S SIZE : Dia of table : 4.6m or 4600 mm

(i) No of Master Rollers : 2 (ii) No. of Slave Rollers : 2 (iii) table speed : 25.53 RPM

Buster Fan (i) Drive : 400 kW

(ii) Speed : 1000rpm (Max.)[Variable speed Motor]

CVRM-3 TYPE : LM 56.3+3 Size : Dia of table : 5.6m or 5600mm

No. Of master roller : 3

No. Of slave roller : 3

Drive Data MOTOR

(i) Make : BHEL (ii) Power required : 3100 kW (iii) Power installed : 3150 kW

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(iv) Input speed (motor) : 990 RPM

GEAR BOX (i) Make : Flender (ii) Type : Bevel helical gearing(3 stages) (iii) Ratio : 38.775:1

Raw material & performance Data

CLINKER GRINDING i) Feed Size

Clinker: 80 % 80 mm & 20 % 150 mm (i) Gypsum : 0-40 mm (ii) Specific Surface : 3400 (Blaine) cm2/gm (iii) Product rate : 117 TPH (OPC)

SLAG GRINDING Feed material : Granulated blast furnace slag

Feed size : 90 % 25 mm & 10 % 150 mm Specific surface : 3400 (Blaine) cm2/gm Product rate : 92 TPH

STORAGE SILO(CVRM) Capacity : 10,000 Tons No. of compartment : 4No’s. Size :Dia-18 m & Height - 52 m

Bag Filter Bag filter is a deducting unit which is used to arrest the dust (cement

particles) from the dusty air and releases only clean air to the atmosphere thereby preventing air pollution.

Working Principle

Dust filter comprises of chamber inside which a number of filter bags are hung row- wise from the top. The dusty air sucked by a centrifugal (vent) fan when passes inside this chamber, dust particles are deposited on these bags and only clean air is released to the atmosphere through stack. Then purging is done row-wise by compressed air operated by solenoid valves set

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timingly. Then dust drops down to the hoppers and conveyed through rotary airlock.

Technical Data

Drive (kW) : 2100 kW Mill Fan speed : 1000 RPM

Fig - xvii

Packing & Dispatch The cement is dispatched by rail and road using wagon loaders and

truck loaders respectively. The entire product is packed by high capacity electronically automatically controlled16 nozzle ENEXCO rotopackers.

Packing House

It is the final or terminal unit of our cement factory where finished product i.e. cements is packed in bags, subsequently dispatched by wagons or trucks. For temporary storage of various quality prior to being packed by packing M/C, there are 17 No’s. of cement silos in which cement is stored and thereafter it is conveyed to the packing machine hoppers through air slide and

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elevators via vibrating screen for packing purpose. There are 5No’s. of Rotopacker M/C in our packing house and each has 16 spout for feeding and packing empty bag. Naked cement from hopper is fed to packing M/C at controlled rate and packed in bags containing 50 Kg .Then packed bags are conveyed to the points of loading by means of belt conveyor arranged in respective routes from where they are loaded to the wagons or trucks by wagon loaders or truck loaders respectively.

Main Equipment:-

Roto Packer : 5 No’s Wagon loader :8 No’s Truck loader : 8 No’s Compressor : 4 No’s Vinnar Conveyor : 12No’s Cement Silo : 17 No’s

Roto Packer

This is a 16 spout packing M/C .This machine rotates by a variable speed belt drive arrangement at a speed of 2.5 rpm. Naked cement after being extracted from storage silo is filled into the packing M/C hoppers via vibrating screen. Two persons are standing and feeding the valve bags onto the filling nozzles. The bags are caught by pneumatically catching system and the bulk material (cement) from hoppers is passed through filling impellers (driven by individual motors) into valve bags with course and fine flow control .

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Environment Protection Activities The company has adopted Zero discharge concept.

LIST OFENVIRONMENTAL SAFEGUARD ACTIVITIES TAKEN IN AND AROUND THE SURROUNDING Control of Stack emission Control Fugitive dust emission Control of SO2 and NOx gas emission

Management of solid & Hazardous waste

INITIATIVE TO CONSERVE NATURAL RESOURCES Utilization of minimum quantity of clinker in PSC by maximizing slag

consumption. Use of flyash from Sponge Iron plant as raw material.

Reduction in power consumption through various techniques. Installation of rain water harvesting systems in the plant & colony.

Recycling of ETP treated water in water treatment plant for machinery cooling and dust suppression.

Fig - xix

NEW INITIATIVES TOWARDS ENVIRONMENT Installation of Clinker silo for clinker storage. Covered shed for raw materials with Stacker & Reclaimer working inside.

Covered conveyor belts for raw materials transportation.

Deployment of Vacuum Suction Road Sweeping Machine to control fugitive dust on the roads of plants and Colony.

Installations of Bag house in Kiln & VRM

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CONCLUSION It was a great experience working under the supervision of

such great dignitaries who gave me ample time and made me understand every bit of the process and clarified all my doubts. It was great experience to be under the guidance of the members of the KHD dept.

OCL, believes and aim at total quality in their products and services to satisfy their Customers. They are committed to continuously improve performance of the Environment and Occupational Health and Safety Management System For

sustainable development. OCL India believes sustained growth of business lies on triple bottom line that is growth of people around there operation, protection of environment where they operate and profit from their business. They understand wellbeing of the community around there business which helps in growth of business and hence they value people around their operational locations and promote inclusive growth. The knowledge gained during the training would help me in future and cherish my life.