TATA STEEL REPORT SUBMITTED.docx

8/10/2019 TATA STEEL REPORT SUBMITTED.docx

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INTRODUCTION

Tata Steel Limited (formerly Tata Iron and Steel Company Limited (TISCO)) is an

Indianmultinationalsteel-making company headquartered in Mumbai, Maharashtra, India, and a

subsidiary of theTata Group. It was the12th largest steel producing company in the world in2012, with an annualcrude steelcapacity of 23.8 million tonnes, and the second largest private-

sector steel company in India (measured by domestic production) with an annual capacity of 9.7

million tonnes afterSAIL.

Tata Steel has manufacturing operations in 26 countries, including Australia, China, India, the

Netherlands, Singapore, Thailand and the United Kingdom, and employs around 80,500 people.

Its largest plant is located inJamshedpur,Jharkhand.In 2007 Tata Steel acquired the UK-basedsteel maker Corus which was the largest international acquisition by an Indian company till that

date. It was ranked 471st in the 2013 Fortune Global 500 ranking of the world's biggest

corporations. It was the seventh most valuable Indian brand of 2013 as per Brand Finance.

On February 12, 2012 Tata Steel completed 100 years of steel making in India.

Incorporated in 2005, Hooghly Met Coke (HMC) is a joint venture involving Tata Steel and the

West Bengal Industrial Development Corporation (WBIDC). Tata Steel holds a 98-per cent stake

in the company.

HMC is setting up a greenfield project at Haldia, West Bengal (in eastern India) with a proposed

capacity of 1.6 million tonne of metallurgical coke. The project will supply metallurgical coke tothe blast furnaces of Tata Steel at Jamshedpur, and for sale in the domestic and internationalmarket. Designed to meet stringent environmental norms, the plants waste heat will be

harnessed for power generation by Tata Power Company.
http://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/Steelhttp://en.wikipedia.org/wiki/Steelhttp://en.wikipedia.org/wiki/Mumbai,_Maharashtrahttp://en.wikipedia.org/wiki/Mumbai,_Maharashtrahttp://en.wikipedia.org/wiki/Tata_Grouphttp://en.wikipedia.org/wiki/Tata_Grouphttp://en.wikipedia.org/wiki/Tata_Grouphttp://en.wikipedia.org/wiki/List_of_steel_producershttp://en.wikipedia.org/wiki/List_of_steel_producershttp://en.wikipedia.org/wiki/List_of_steel_producershttp://en.wikipedia.org/wiki/Crude_steelhttp://en.wikipedia.org/wiki/Crude_steelhttp://en.wikipedia.org/wiki/Crude_steelhttp://en.wikipedia.org/wiki/SAILhttp://en.wikipedia.org/wiki/SAILhttp://en.wikipedia.org/wiki/SAILhttp://en.wikipedia.org/wiki/Jamshedpurhttp://en.wikipedia.org/wiki/Jamshedpurhttp://en.wikipedia.org/wiki/Jamshedpurhttp://en.wikipedia.org/wiki/Jharkhandhttp://en.wikipedia.org/wiki/Jharkhandhttp://en.wikipedia.org/wiki/Jharkhandhttp://en.wikipedia.org/wiki/Fortune_Global_500http://en.wikipedia.org/wiki/Fortune_Global_500http://en.wikipedia.org/wiki/Brand_Financehttp://en.wikipedia.org/wiki/Brand_Financehttp://en.wikipedia.org/wiki/Brand_Financehttp://en.wikipedia.org/wiki/Fortune_Global_500http://en.wikipedia.org/wiki/Jharkhandhttp://en.wikipedia.org/wiki/Jamshedpurhttp://en.wikipedia.org/wiki/SAILhttp://en.wikipedia.org/wiki/Crude_steelhttp://en.wikipedia.org/wiki/List_of_steel_producershttp://en.wikipedia.org/wiki/Tata_Grouphttp://en.wikipedia.org/wiki/Mumbai,_Maharashtrahttp://en.wikipedia.org/wiki/Steelhttp://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/India


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What is Coal?

Coal is a fossil fuel formed from plants that were buried millions of years ago. The high

temperature, high pressure conditions underground transformed the plants physically and

chemically forming coal.

CLASSIFICATION OF COAL:

COAL

Based on rank Based on physical changes

Peat Coking coal

Lignite

Sub-Bituminous Non coking coal

Bituminous

Anthracite

Petrographic constituents of coal:

The organic components of coal observed under microscope are classified as maceral. It

describes the shape and nature of the microscopically recognizable (organic) constituents of

coal. Each macerals has a distinct set of physical, chemical, and technological properties.

Macerals are divided in three groups

1) Liptinite: Relatively enriched in hydrogen in compared with the other two groups, black

in colour.

2)

Vitrinite: It has a greater carbon content, medium grey in colour.3) Inertinite:It has an intermediate chemistry in between liptinite and intertinite, white in

colour.

Groups are distinguished from each other by their reflectance and fluorescence.

Fig-1(Different components in coal)


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3.Plasticity-

It is a property of amaterial to undergo a non-reversible change of shape in response to

an applied force. On heating above around 4000C coal goes to plastic state (thermal

stress) coke making is a plastic change.

Plastic Tests:-

crusible swelling number / Free swelling index

It measures the degree of free swelling, makes a preliminary separation of

coking and non-coking coals. Test involves rapidly heating one gram coal (-60

mesh ; 0.25 mm) in a translucent silica crucible with a lid to 8200C for 1.5 in an

electric furnace minutes. The profile of the coke button obtained is compared

with a set of standard profiles numbered 1 to 9. Lower number means lower

free swelling or coking power of coal.

Lower number means lower free swelling or coking power of coal. Lower limit

for coking coal is 3.5 . CSN is not additive.

Gieseler fluidity

Coking coals on heating through successesive transient stages of softening-

swelling-semi plastic/plastic-solidifying. This behavior has been termed as fluid

behavior.during coke making coal melt and fuse into coke.This permits the

fluid constituents to combine with The non melting fraction to form a strong

coke. Fludity is measured by Gieseler parameter.

Fig-2 (Effect of

temperature on fluidity)


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4. Reactive macerals:-

Vrinite is generally the most frequent and accordingly,the most important maceral

group occurring in bituminous coals in the form of vitrin layers. For a good coking

coal precentage of vitrinites is important parameter as it is the reactive maceral

and among which V9V14 is reactive part.

5. Roga Index:-

1g coal sample(-2.0mm in size) is mixed with 5 g anthracite and heated in a crucible at

800(+-)10C for 15 mins.The coke residue is subjected to abrasion in a drum of std. size

for 5 mins at 50 rpm and % of the +1 mm fraction , is reported as a rogaindex.Prime

coking coals generally have a RI >30.

6.Mean max reflectance: -

Vitrinite reflectance is measured by using polarized but monochromatic light of knownwavelength. The amount of light reflected keeping the polarizer at 45 position by the

vitrinitemaceral is measured.the mean of 100 readings for any single seam coal and 250readings for any blend is taken as the reflectance of coal.The mean of these reflectance is

termed as mean max reflectance.

In coke oven naturally occuring coals are converted into coke which is suitable for use in

blast furnace.Coalcant be use as such in blast furnace because of

Its poor crushing strength

Poor combustibility

Presence of volatile matter

Swelling propeerty

It is therefore transforms into a hard porous mass, devoid of volatile matter

called coke by carbonization process. Depending upon its properties coke is

known as hard coke.Metallurgical coke is also known as blast furnace

coke,a macro porous carbon material of high strength , is produced by

carbonization of coal of specific rank or of coal blends. To get coke having

the above quality, the coal which is used for carbonization is called

metallurgical coal.


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Properties of Good COKING COAL:-

i) ASH% 8-10

ii) Moisture% 9 approx

iii) VM% 2123

iv) Fluidity 3001000 ddpmv) Sulfur% 50

ix) Vitrinite% >55

What is Coke?

Coke is a fuel with few impurities and a high carbon content usually made from coal. It is a solid

fuel made by heating coal in the absence of air so that the volatile components are driven off.

Different types of coke based on size:-

Coke Size USE

i) Metallurgical/ BF coke +30 to -100 mm In Blast furnace

ii) NUT Coke +10 to -30 mm COREX plant/Fondry shop/BF

separately

iii) COKE BREEZE


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Coke Oven:

A coke oven is a device used to produce coke, a product that is derived from coal. The

mixing and heating of bituminous coal at temperatures ranging from around 1000 c to

2000

c within the airless oven yields the coke byproduct. This device is a crucial part of

the coke making process.

There are mainly two methods of coke production;

Recovery type

Heat-Recovery type

By- product Recovery coke ovens:

In this process selected coals are blended and crushed for proper bulk density control,

blended coal is charged into a no of slot ovens shares a common heating flue withadjacent oven. Coal is carbonized in a reducing atmosphere and the off gas is collected

and sent to the by-product plant to recover various by-product. Hence this process is also

known as by-product coke making. Here combustible gases are available for downstream

processes as fuel.

Coking phenomenon in recovery ovens:

In recovery type ovens the charge of coking coal is heated in the oven, the coal particles

surface of the chamber wall become plastic starting at about 360-4750C . In the

temperature range of 475-6000

C , there is a marked evolution of tar, and aromatichydrocarbon compounds, followed by re-solidification of the plastic mass into semi coke.

As the heat front advances to the next layer, the layer closest to the hot surface

solidifies. The sequence continues, layer by layer, and the plastic layers from the both sides

of the wall forming an envelope, advance and meet at the centre of the charges as layers

near the hot surface get transformed from semi-coke to coke. In the temperature range 600-

10000C ,the coke stabilization phase begins. This is characterized by contraction of coke

mass, structural development of coke and final hydrogen evolution. Gases and vapor from

the inner layers escape, through fissures developed due to shrinkage in the layers of semi

coke and coke.

Heat-Recovery coke ovens:

In heat recovery ovens also known as beehive ovens, coal is carbonizedin large oven chambers

under negative pressure. The carbonization process takes place from the top by radiant heat

transfer and from bottom by conduction of heat through the sole flue.Since the by-products are


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not recovered, the process is called non recovery coke making. In some cases, the waste gas exit

into a waste heat recovery boiler which converts the excess heat into steam for power generation,

hence the process is called heat recovery coke making.

Coking phenomenon in Heat-Recovery ovens:

In the heat recovery beehive ovens, the coking proceeds downwards from the top & upward from

bottom, during which the coal at increasing depths, passes through a plastic state as the

temperature rises, leading to vertical shrinkage. This results in expansion and contraction of the

charge. The coke is criss-crossed by large numbers of irregular vertical fissures, which imparts

long volumetric structure . The structure provides an indication by which non recovery oven coke

can be distinguished from by product oven coke.

Attractive features of heat-recovery coke oven:

Operation of carbonization chambers under negative pressures.

Less pollution, environment friendly,

No carbonization wall pressure

Ability to work on single coal, wide range of blend tank, allows higher amount of

low rank, non coking coals.

As majority of is direct radient heating from coal VM combusting above charge,

hence higher temperature, Coaking time adjustable without affecting productivity,

Lower installation cost and simple operatation system compared to recovery tipe

coke ovens

Flat bed carbonization

Supply of air in both carbonization chamber as well as in sole flue.

Fig -3(Heat Recovery Process flow diagram)


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Coke Oven in TATA STEEL Plant : -


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Material Balance for Heat recovery type coke ovens:

Energy balance for heat recovery coke ovens:

In this plant heat rocvery type coke oven is used.

HEAT-RECOVERY

OVENS

FLUE GAS: 3.25TONSWET COAL- 1 TON

(0.92 TONS,DRY)

WET COKE

DRY 0.66

AIR: 4.91 TONS

Combustion heatliberated 2.525 M

Kcal,100 %

Heat

loss(convection+radi

ation)0.533 M

Kcal,21.1%

FLUE GAS: Co2,So2,H2O,N2,O2

Sensible heat: 1433 Mk(57 %)

Latent heat: o.27 MK(10.7 %)

SENSIBLE HEAT:

0.284MKCAL(11.2 %)WET COAL (1 TON)

C,H,NO,H2O,S,ASH

0.533 KCAL(21.1 %)

AIR,O2,

N2,H2OCOKE 0.66 T


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Carbonization process:-

Fig-4( Carbonisation in HR oven)

It occurs in 3 stages.

Pre- plastic stage:

Low temperature volatilization occurs, moisture & evolution of CO2 occurs at a

temperature less than 1200C . Temperature in between 120-375

0C initially

methane,CO, nitrogen evolution started.

Plastic stages:

At a Temperature range between 375-4750C coal becomes plastic encompassing

extensive molecular disruption and expulsion of volatiles. Volumetric changes starting

with initial contraction followed by expansion and a 2nd

contraction occure with

rise in temperature.

Post- plastic stage:

At a temp. range 475-6000C re-solidification of plastic mass into semi coke and

evolution of tar and aromatic hydrocarbon occure. Temperature rangr in between

600-10000C contraction, structural development of coke and finally hydrogen

evolutions occurs.


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Fig -5(Physically changes during carbonization of coal)

Design Parameters Of The Plant:

1) Dry gross coke production at 95% oven utilization- 1.6 MTPA

2) Type- Heat recovery typew adopting stamp charge technique

3) Coal blend-a) prime coking coal- 45-55% & b) semi soft coking coal- 45-55%

4) Proximate analysis of coal blend: moisture- 9% , ash- 8-10% , volatile matter- 22-

24%, sulpher- 0.6%

5) Coking properties of coal blend: a) CSN- 5-6 & b) Mean reflectance of vitrinite-1

6) Coal bluk density: 1.05- 1.1 ton/m

7) Coal size: a) fraction below 0.5 mm- 35% & b) fraction below 3.0 mm- 90%

8)

Coke quality requirement: a) moisture-4% b) ash-11% c) volatile matter- 1% d)sulpher- 0.6% e) M40- 80 f) M10- 7 g) CSR- 68 h) CRI- 18-23

9) Gross carbonization time- 64-66 hrs

10)No of oven pushing per day- 132

11) Gross coke yield over dry coal- 75% with 24% VM coal

12)Waste gas generation- a) flow- 10,08,000 Ncum/hr b) Temparature- 1000c

COAL SOFTEN MELT

FUSE

SWELLRESOLIDIFIEDCOKE

PRE-PLASTIC STAGE

PLASTIC

STAGE

POST-PLASTIC STAGE


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Calculations for coke :-

Yield = 100coal VM + coke VM3% burning loss

Coke = yield * dry coke

Yeild = 100 -23 +.63

=74.6

Coke = 74.6 * 50*(8%)

= 34 tonns

If 50tonns of coal is charged, 34 tonns of coke can be got.

Total coke manufactured yearly = 1.6 million tons.

Per shift charging = 34/3 = 11 or 12

Overall Process Flow Diagram Of the plant:


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Coal& Coke SampleTesting:

A Q.C. Laboratory is present in the plant where coal & coke sample is tested to calibrate the

property and the composition of the sample with respect to other one. For testing coal sample,

here proximate and analysis have been done. Also HGI & plasticity test is done for testing the

coal samle. The equipment used for this purpose is Hot air oven, LTGK Furnace, Muffle furnace.

In case of coke sample testing, the experiment done in the laboratory is CSR, CRI Test , ARS

test. The equipment used here is eye drum, pulverizer, vibrator sieve, roller crusher, jaw crusher,

micum drum.

Raw material(Coal) handling section:

Wagon Tippler & side arm charger

1) Coal stacker cum reclaimer

2) Blending bunker

3) Moisture addition

4) Crusher house

5) Coal conveyor

6) Belt scale

7) Cross belt magnetic separator

8) Hanging magnet

9) Metal detector


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Fig-6(Layout of HMC Coal circuit)

Coal blend used:-

Fivetypes of coal are used for economical optimization;-

1. Bhelatend (25%)

2. West bokaro (20%)

3.

Saraji (30%)4.

CSS(10%)

5.

Kestral (15%)

From these, Blelatend& west Bokaro from own coliary&Saraji, CSS, Kestral

are imported.

Basic description:a) The coal is unloaded in underground hopper of wagon tippler of adequate capacity, from

rail wagon by wagon tippler. One tippler complete with the side arm charger is installed

for this purpose.


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Fig 7(Wagon Trippler) Fig 8(Side Arm Charger)

b) The above stream designed for continuous duty of 24 hrs. per day for any of following

flow routes.i) the tippler complex to coal stock yard. ii) tippler complex to blending

bunkers iii) from coal stock yard to blending bunkers iv) from blending bunker to coal

tower.

Fig 9(Coal Stacker cum Reclaimer)

c) Conveyor CL-1 conveys coal to conveyor CL-2 at junction house(JH-1).

d) Conveyor CL-2 conveys coal to conveyor CL-2A at junction house(JH-2) via pent

house(PH).

e) CL-2A shall feed coal to CL-3(ground conveyor ) at JH-2A.

f) CL-3 conveys coal to CL-4, JH-3.

g) Conveyor coal from CL-4 discharge to CL-5 at JH-4.

h) CL-4 discharge coal at blending bunker building.

i)

Coal from blending bunker is discharged to CL-6 through 8 nos.j)

One no of moisture measurement transmitter MG-1 is provided on CL-6 for continuous

moisture measurement of coal before entry of crusher house.

k) CL-6 feed coal to crusher house. MD-1 is provided on CL-6 to detect magnetic material.


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Fig 10(Parts of Conveyor)

l) Coal from CL-6 at crusher house passes through 3 sets of rodgates.

m)Crusher coal from crusher of sizes (-) 3mm is discharged to CL-7 at crusher house.

n) CL-7 drops coal on to CL-8 at JH-5. MD-2 is provided for this purpose.

o) CL-8 discharge crushed coal to one no of RCL-1 at JH-6.

p) CL-9 & CL-11 discharge to either coal tower 1 or CL-10 & coal tower 3 or CL-12

through RCL-2 & RCL-6 respectively.q) CL-10 and CL-12 feed crushed coal to coal tower -2 & 3 respectively through RCL-4& 7

respectively. Two belt scale BSCL-5 & 7 are provided on conveyor CL-10 & CL-12

respectively.

Coke Oven Section:

Battery Construction:

The coal coke is firstly heated by the heat accumulated in the fire tunnels of main

walls and oven bottom and fleu gas then separated, which is burnt incompletely by

adjusting the primary air door on the oven top. Due to inadequate air introduction

retaining atmosphere from with in the chamber top constitutes a protective layer for

coal cake. The remaining flue gas goes down through the descending fire tunnels to

four linked arch tunnels. There are four secondary air tunnel, by adjusting the


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secondary air door fresh air is introduced into the sole to burn the flue to produce

heat. The temperature of oven bottom is controlled by means of thermocouple so as to

control the quality of introduced air and secure a uniform temp rise of carbonization

chamber. The temp of the chamber is 1050-1300c.

Fig11(Cross Section of HR oven)

Fig 12(Longitudinal cross section of oven)


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Oven top is of barch structure in order to avoid burning- out of coke the primary air

doors are installed on the oven top so as to form a protective layer between coal

burning zone.

Oven Door:

Oven door is divided into two parts. The upper door is fixed and lower door is flexible. Such

design can reduce dust emission and operating weight of oven doors.


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Path of Fluegas:

Fig-13(Top View of Combustion Chamber)

Oven top Oven sole Uptake Bridge pipe Bridge pipe

damper

Branch HeaderB.H.Dam

erCommon

header

Outer

Header

Boiler Inlet

Dam er

Boiler

ID Fan

BoilerOutlet

DamperChimney

Bypass

Damper


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Coke oven Machines:-

a) Coal tower

b) Stamping station

c)

Coal charging cum coke pusher car

d) Coke receiving cum quenching car

Fig-14(Stamping Station) Fig 15(Coal Charging Cum Coke pushing car)

Coke Quenching System:

Function of quenching station is to quench the hot coke coming from oven carried out by hot

coke quenching car. Coke quenching system is consists of a coke quenching tower with

dedusting equipment and overhead water tank, two sets coke quenching pump, one set of slurry

pump, fresh water tank, coke breeze deposit device, coke breeze dehydrating platform and

electrically opetaredtelpher grab bucket with single grider EOT crane.


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Coke handling section:

Fig-16(Diagram of Coke Circuit)

Brief description:

a) From four rows four no of wharf conveyor WCK-1,2 & 5,6 feed coke to two common

wharf conveyor WCK 3&7 at JH-A&C respectively .

b) At JH-B&D coke is discharged to RCK-1&3 respectively which feed coke either to

WCK-4&8 or to CK-1 respectively.

c) Ck-1 discharge coke to RCK-2 at screen house.

d) RCK-2 feed coke either to VS-1&2 or to CK-3.

e)

The screened coke of size 10mm is discharged from screen to Ck-2.

f) Screened hard coke of size 10mm is by RCK to yard conveyor CK-3.

g) At JH-8 one surge hopper having 100 cum is provided. One vibrating feeder is provided

to withdraw the material from surge hopper. From the vibrating feeder material is feed to

wagon loading conveyor CK-5 at JH-8.


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Refractories:

Why Refractories are used?

To resist material loss and mechanical failure during the interaction between deferent state of

material at elevated temperature in oven/ kiln/furnace so that we can get desired product

Material loss process

Process of material loss due to interaction between

different states of material and atmosphere:

Erosion:A process of material loss while a solid interacting with fluid (Liquid/Gas).

Abrasion:A process of wear and tear resulting from the interaction between two solids.

Corrosion:A process of decay of solid because of chemical reaction

Definition

Thus suggested definition of refractory:

An inorganic material which can offer resistance towards corrosion, erosion and abrasion

process without mechanical failure even at elevated temperature.

Thus, Refractories should be thermally, mechanically and chemically stable when it get

operated.

Some metals are also showing high refractoriness like

Refractories Selection parameters

General Refractory Selection Parameters:

1. Interacting atmosphere of Furnace/Kiln

2. Degree of interaction and criticality of Zone

3. Operating Temperature & Pressure


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4. Size of Furnace/Kiln

5. Economic consideration etc.

Refractories Properties & Tests

1.

Chemical Analysis

2. Apparent Porosity (AP)

3. Cold Crushing Strength (CCS)

4. Refractoriness Under Load (RUL)

5. Pyrometric Cone Equivalent (PCE)

6. Abrasion Test

7. Permanent Linear Change (PLC)

8. Thermal Conductivity Etc.

Refractory classification

There are two ways of classifications of Refractories:

Physical Classification:

Chemical Classification:

i)

Shaped Refractory

Unshaped/Monolithic

Refractory

Example: Bricks,PCPF,Ceramic

Board etc.

Example:

Motor,Castable,PlasticMass,Guintin

g Refractory tap hole clay etc.


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ii)

iii)

Refractor ies used HMC coke oven: -

SL

No

Type of Refractor ies Area of Appli cation

1 Silica Bricks Interior lining of oven except mouth portio

refractory

2 High Alumina Brick Oven mouth wall

3 Fire Clay Bricks Battery areas directly exposed to air

4 Insulation Bricks Flue gas carrying pipes

5 Refractories Mortar Act as an adhesive between two Bricks joi

6

Ceramic Board Oven door and flue gas pipe back up lining

7 Acid resistance Bricks Wharf & other High Abrasive area


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8 PCPF Refractories Dampers

9 Castable (LC-45) Oven Door Lining

Why silica refractory?

Silica is an Acidic Refractories

Very Low thermal expansion coefficient(0.33X10-6

/Deg C)

Volume stability in certain range of temperature (after 600

oC)

Very Good thermal conductivity.

Excellent spalling resistance at high temperature

High Abrasion Resistance

High Creep Resistance & RUL

Prolong life

Thermal conductivity comparison

Below graph represent a comparative thermal conductivity figures:

Fig-17


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General Specification of Silica Bricks:-

General Properties

Some facts about silica refractory

Raw materials: Quartz, Quartzite, Ganister, Sand Stone

In spite of low Raw material cost it is costlier due to lower yield i.e high rejection.

Heating and cooling should be super controlled and very slow to avoid rejection.

Prolong inhalation of silica dust may cause of chronic disease like silicosis. Effect

respiratory system

Generally use at Oven like Hot Stove, Coke oven, Regenerator of coke oven, Glass

melting furnace crown etc.

PHASE TRANSFORM

Silica Polymorphs: Quartz, Trydimite, Crystobalite

There are two ways Silica changes its phase:

1. Reconstructive: Caused by breaking of bond in lattice. Example Quartz, Tridymite,

Cristobalite

2. Displacive: Caused by shifting of atom/bond from their lattice : - Quartz, -Quartz, -

Tridymite, -Tridymite, - Cristobalite, - Cristobaliteetc


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(a)

(b) (c)

Fig-18

As long as temperature variation is very slow the above conversion is fully reversible

Increase in temperature resulted in more vibration of atoms in the crystal which require

more space hence it starts expending during temperature increase.

Trydimitephase is most desirable phase in coke oven silica refractory.

Best operating temperature range of Silica Bricks is 8700C to 1470

0C i.e in trydimite

phase, However in worst condition it should not be lowered than 5730C 600

0C.

The above constraint compel to carry out refractory repairing job at high temperature.

Hence, we should maintain the permissible temperature range by optimizing time of oven

door changing, opening, closing & other activity caused temperature drop.


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Safety Management in this plant:

Conveyor Safety:

Conveyor are efficient method of transportation. However, they can also be one of the

most dangerous elements of plant in a workplace if safe operating and maintenance

practice are not maintained.

Twelve Fundamental Conveyor Safety Rules:

a) Dont perform service on conveyor until motor disconnect or is locked out.

b) Service conveyor with only authorized maintenance personnel.

c) Keep clothing, fingers, hair, and other parts of the body away from conveyor. Loose

garment shall be avoided.d) Dont climb , step, sit or ride on conveyor at any time.

e) Dont load conveyor more than the design limits.

f) Dont remove or alter conveyor guards or safety devices.

g) Know location and function of all stop/start controls.

h) Keep all stopping/starting control devices free from obstructions.

i) All personnel must be clear of conveyor before starting.

j) Operate conveyor with trained personnel only.

k) Keep area around conveyors free from obstructions.

l) Report all unsafe condition & practices to your supervisor.

Unsafe conditions & environmental causes &prevention:

a) Moving conveyor in a open gallery are a crucial safety breach that can be minimized

with good training and employee awareness.we are equipped with adequate conveyor

guarding in every situation.

b) Defective conveyor equipment is unprotective and dangerous. When conveyor are not

running at correct speeds, belt tensions or in other ways accident can result. People

shall be trained to avoid these situations.

c) Conveyor that are arranged hazardously can be a source of accidents. The conveyor

layout is made so that it allows foot traffic safely with moving conveyor training canhelp them avoid injuries.

d) Another possibility is that overhead or elevated conveyors may result in conveyed

items that fall possibly causing injuries. To avoid this, conveyors shall be guarded

either with railings, safety netting or other fall protection metods.


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e) At times people will deactivate safety devices to expedite work or to quicken the

pace. We should understand what devices are installed on a conveyor to make it safer

and be sure those are always operational and in place.

Use of personal protective equipments:

Helmet with chin strip tightly fitted.

Safety Goggles.

Safety Shoes.

Hand Gloves.

Mask for protection from dust.

High visibility vest

IMS

1. Health and safty policy

ISO 18001:2007

2. Environmental policy

ISO 14001: 2004

3. Quality policy

ISO 9001 : 2008


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CONCLUSION:

The visit to the plant was highly interesting and it was a wonderful learning process.Raw material unloading to coke loading through carbonization process everything

done here is in very well defined way. Safety level in this plant is very high. Regular

monitoring & maintenance of coke oven system gives an idea of health carbonization

process, formation of coke. Lastly the most important feature of the plant is that the

process of the plant is eco-friendly. The emitted flue gas from the chimney do not

pollute the environment.


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REFERENCES:

1. Hooghly Met Coke training manual

2.

Internet

3. "History of Tata Iron & Steel Co. Ltd.". FundingUniverse.com. Retrieved 31

August 2013.

4. "History of Tata Steel".steelonthenet.com. Retrieved 31 Aug 2013.

5. Tata steel-wikipedia,the free encyclopedia.
http://www.fundinguniverse.com/company-histories/tata-iron-steel-co-ltd-history/http://www.steelonthenet.com/kb/history-tata.htmlhttp://www.steelonthenet.com/kb/history-tata.htmlhttp://www.fundinguniverse.com/company-histories/tata-iron-steel-co-ltd-history/

Documents

TATA STEEL REPORT SUBMITTED.docx