1. About Bokaro Steel Plant
Bokaro Steel Plant – the fourth integrated steel plant in the Public Sector-
started taking shape in 1965 in collaboration with Soviet Union. It was originally
incorporated as a limited company on 29th January 1964, and was later merged
with SAIL , first as a subsidiary and then as a unit, through the Public Sector Iron
& Steel Companies (Restructuring & Miscellaneous Provisions) Act 1978. The
construction work started on 6th April 1968.
The plant is held as the country’s first swadeshi steel plant, built with maximum
indigenous contents in terms of equipment, material and know-how. Its first
blast furnace started on 2nd October 1972 and the first phase of 1.7 MT ingot
steel was completed on 26th February 1978 with commissioning of the third
blast furnace. All units of 4MT stage have been already been commissioned and
the modernisation has further upgraded this to 4.5MT of liquid steel.
Bokaro Steel Plant is designed to produce flat products like HOT ROLLED COILS,
HOT ROLLED SHEETS, COLD ROLLED COILS, COLD RLLED SHEETS,TIN MILL
BLACK PLATE(TMBP) and GALVANISED PLAIN and CORRUGATED (GP/GC)
SHEETS. Bokaro Steel Plant has provided a strong raw material base for a variety
of modern engineering industries including automobiles, pipe and tube, LPG cyl-
inder, barrel and drum producing industries.
Bokaro Steel is working towards becoming a one-stop- shop for world-class flat
steel in India. The modernisation plans are aimed at increasing the liquid steel
production capacity, coupled with fresh rolling and coating facilities. The new
facilities will be capable of producing the most premium grades required by the
most discerning customer segments.

2. List of Plants Visited
1. RAW MATERIALS HANDLING
PLANT [ RMHP]
2. SINTER PLANT
3. COKE OVEN & BY-PRODUCT
PLANT [ CO &BPP]
4. BLAST FURNACE
5. STEEL MAKING SHOP &
CONTINUOUS CASTING SHOP
[ SMS & CCS]
6. RESEARCH AND CONRTOL
LABORATORY [ RCL ]

3. Raw Material Handling Plant [RMHP]
This plant receives, blends and stores different raw materials including iron
ores fines, iron ore lumps , dolomite, limestone, and coke etc. And vends
these raw materials to the Blast Furnace, Sinter Plant and Refractory mate-
rials plant as per their requirements. It also maintains a buffer stock to take
care of any supply interruptions.
This plant consists of various machinery and are list as follows:
 Rail
 Car Pushers
 Wagon Tipplers (4 in number)
 Stackers (7 in number)
 Re-claimers (6 in number)
The raw materials arriving from various mine being carried on rails
are unloaded at Tipplers. In this section the wagon carrying the raw materi-
als is rotated at angle of 170 degrees to unload the raw materials.
Subsequently, these raw materials are carried through conveyers and stored in
the form of heap, separate for each raw material. Now, Re-claimers blend and
mix the different quality of raw materials for e.g., Iron ore fines from different
mines and hence a homogenous composition is made and distributed to its
customers mainly Blast Furnace and Sinter Plant.
Some 9MT of different raw materials viz.
iron ore fines & lumps, Limestone (BF &SMS
grade), Dolomite lumps and chips, hard coal
and manganese are handled over a year.
Fig. Wagon Tippler Machine

4. Fig. Raw material Stacker
DIFFERENT TYPES OF RAW MATERIALS AND THEIR SOURCES
RAW MATERIAL TYPE SOURCES
IRON ORE FINES & LUMPS KIRIBURU,MEGHATA-
BURU,GUA,BOLANI -
MANOHARPUR,KATLA
HIGH SILICA/SP GRADE LIMESTONE BHABANTHPUR, KHANBHANJARI
HIGH SILICA/SP GRADE DOLOMITE BHABANTHPUR,BIRMITRAPUR
LOW SILICA/SMS GRADE LIMESTONE JAISALMER,DUBAI,OMAN
LOW SILICA/SMS GRADE DOLOMITE BHUTAN,BELHA
EXTERNAL AND INTERNAL HARD COKE IISCO,DPL,NINL,MBEB,VISA
EXTERNAL AND INTERNAL SINTER IISCO,NINL,RSP

5. CUSTOMERS OF RMHP
 BLAST FURNACE- Lump iron ore, external and internal sinter, hard coke,
quartzite
 SINTER PLANT- Iron ore fines and flux
 RMP- Low silica limestone and dolomite.
FIG. IRON ORE FINES

6. SINTER PLANT
Sintering is a process of agglomeration of fine mineral particles into a po-
rous and lumpy mass by incipient fusion caused by heat produced by
combustion of solid fuel within the mass itself.
RAW MATERIALS USED FOR SINTERING
 Iron ore fines
 Flux (lime stone & dolomite)
 Coke breeze
 Waste Materials:
 Flue dust (From Blast Furnace but added in RMHP)
 Mill scale (From Slabbing Mill, H.S.M.&CCS)
 L.D. Slag (From S.M.S.)
 Lime dust (From R.M.P.)
 Sinter return (Own generation)
DIFFERENT EQUIPMENTS OF SINTERING PLANT
 RAW MATERIAL BINS AND WEIGH FEEDERS
 MIXING AND NODULIZING DRUM WITH WATER INJECTION SYSTEM
 SURGE BIN-SECTOR GATES WITH SERVO DRIVES AND FEED DRUM
 IGNITION HOOD FURNACE WITH BURNERS
 SINTER MACHINE-PALLETS with GRATE BARS
 WINDBOXES WITH WASTE GAS MAIN
 SPIKE CRUSHER-WITH CRASH DECK
 DOUBLE ROLL CRUSHER
 VIBRATORY COLD SCREEN FOR HEARTH LAYER
 VIBRATORY SCREEN FOR RETURN FINES
 CONVEYORS, RECEIVING CHUTES AND TRANSFER CHUTES FOR RAW
MATERIAL AND SINTER
 WASTE GAS FAN WITH LCI DRIVE

7.  DEDUSTING FAN FOR PLANT DEDUSTING
 ESPs
 LT and HT DRIVES
 PNUEMATIC ACTUATORS & VALVES
THE NEED OF SINTER:
• To utilize the fines generated during the mining operation.
• To utilize different additives like mill scale, flue dust, hearth slag etc. in
an integrated steel plant.
• The need for charging prepared burden in Blast Furnaces to increase
productivity and lower fuel rate.

8. SINTER MACHINE PARAMETER:
1.Hearth temperature- 1050-1150∘C
2.Machine speed- 1.7-2.0 m/minute
3.Moisture- 8.0±1%
4.Gas pressure- 200mmWc-350mmWc
5.BTP- >180∘C.
COKE OVEN & BY-PRODUCT PLANT[CO &BPP]
In this plant, coal coming from various RMHP is converted into coke by the
process of carbonisation. The coal coming from mines is brittle and generally
has low combustion rate. In the carburization, the coal is heated in coke oven
furnace and the product which we get is called coke or BF coke
The BF coke is harder and has a high combustion rate and is suitable for fur-
ther blast furnace operation.
THERE ARE FOUR SECTIONS IN COKE OVEN PLANT:
1. COAL HANDLING PLANT
2. BATTERY
3. COKE SORTING PLANT
4. BY-PRODUCT PLANT
Coals are of two types-
1. Imported coal
2. Indian coal
Indian coal has low calorific content. So we blend the Indian coal with imported
coal in the ratio of 60:40 percent. Generally, coal of better quality is imported
from Australia, New Zealand.

9. There are 81 silos in which different qualities from different countries coal is
stored. Each silo has capacity of 2500 Tons. After that coal is sent to coal tower
of capacity 3200 Tons.
Now coal is charged into coke oven batteries. There are total 8 batteries and 69
ovens in each. The length and height of the coke oven batteries are 15m and 5m
respectively. The capacity of one battery is 22 Tons. The coal is heated in battery
at 1200-1300∘C for 18-20 hours.
FIG. COKE OVEN BATTERIES AT BSL, BOKARO
FIG. SILOS (These are used to store coal and act as buffer stock in sine die situations)

10. THE FOLLOWING BY-PRODUCTS ARE PRODUCED DURING CARBURISA-
TION:
1. TAR
2. NEPTHALENE
3. AMMONIUM SULPHATE
4. BENZOL
FIG. BY-PRODUCT PLANT

11. BLAST FURNACE
A blast furnace is a type of metallurgical furnace used for smelting to produce
industrial metals, generally iron, but also others such as lead or copper.
In a blast furnace, fuel, ores, and flux (limestone) are continuously supplied
through the top of the furnace, while a hot blast of air (sometimes with oxygen
enrichment) is blown into the lower section of the furnace through a series of
pipes called tuyeres, so that the chemical reactions take place throughout the
furnace as the material moves downward. The end products are usually molten
metal and slag phases tapped from the bottom, and flue gases exiting from the
top of the furnace. The downward flow of the ore and flux in contact with an up
flow of hot, carbon monoxide-rich combustion gases is a counter-current
exchange process.
In contrast, air furnaces (such as Reverberatory furnaces) are naturally aspi-
rated, usually by the convection of hot gases in a chimney flue. According to this
broad definition, bloomeries for iron, blowing houses for tin, and smelt mills for
lead would be classified as blast furnaces. However, the term has usually been
limited to those used for smelting iron ore to produce pig iron, an intermediate
material used in the production of commercial iron and steel, and the shaft fur-
naces used in combination with sinter plants in base metals smelting.
The tuyeres are used to implement a hot blast, which is used to increase the ef-
ficiency of the blast furnace. The hot blast is directed into the furnace through
water-cooled copper nozzles called tuyeres near the base. The hot blast temper-
ature can be from 900 °C to 1300 °C (1600 °F to 2300 °F) depending on the stove
design and condition. The temperatures they deal with may be 2000 °C to 2300
°C (3600 °F to 4200 °F). Oil, tar, natural gas, powdered coal and oxygen can also
be injected into the furnace at tuyere level to combine with the coke to release
additional energy and increase the percentage of reducing gases present which
is necessary to increase productivity.

12. Fig. TUYERES OF BLAST
FURNACE
THERE ARE FIVE BLAST FURNACES IN BOKARO STEEL PLANT OF 2000 CUBIC
METERS FOR PRODUCING HOT METAL .
Bell-less Top charging, modernised double Cast houses, Coal Dust Injection and
cast house slag granulation technologies have been deployed in the furnaces.
The process of iron making is automated, using PLC Charging System and Com-
puter controlled Supervision System. The waste products like blast furnace slag
and gas are either used directly within plant or processed for recycling or re-use.
Design and Features of All Furnaces
Particulars BF1 BF2 BF3 BF4 BF5
USEFUL VOLUME (IN CUBIC METER) 2000 25000 2000 2000 2000
WORKING VOLUME(IN CUBIC METER) 1758 2250 1758 1758 1758
HEARTH DIAMETER(in meter) 9.5 10.2 9.5 9.5 9.5
NO. OF TUYERES 20 28 20 20 20
HOT BLAST TEMP. (⁰C) 1000 1150 1000 1000 1000

13. Top Pressure(kg/cm.sq.) 1.5 2.5 1.5 1.5 1.5
RATED CAPACITY (tonne/day) 2640 4500 2640 2640 2640
FIG. FURNACE CONTROL ROOM OF BLAST FURNACE 2, BSL, SAIL, BOKARO
(OVERVIEW OF BF2)
STEEL MAKING SHOP
After production of hot metal in blast furnace, it is sent to steel making shop for
production of steel.
Ladle of pig iron is sent to mixer. Ladles are brought to SMS from BF through lo-
comotive engine. The capacity of each ladle is 100 tonnes.
There are two mixers in SMS each having capacity of 2500 tonnes.
The functions of mixers are as follows:

14. 1. To maintain temperature
2. To homogenize the composition
3. To storage
Then it is sent to LD Converter. There are two LD Converters each of capacity 300
tonnes.
Pig iron is charged into converter and then through lance pipe the melt is oxi-
dized. Thus oxidizing all the impurities in melt and forming lighter oxides which is
separated out due to lesser specific gravity.
The oxygen supply by the lance is 99.9% pure. The blowing time is about 15-18
minutes. There is exothermic reaction takes place. The temperature range is
1700-1800∘C.Now it is sent to secondary refining unit (SRU). In SRU we use Ar
gas.
The main functions of SRU are:
1. Homogenization
2. De oxidation
3. Temperature & composition adjustment
4. Desulphurization
5. Dispatching to casting
Bokaro has two Steel Melting Shops - SMS-I and SMS-I I. SMS-I has 5 LD convert-
ers of 130T capacity each. It is capable of producing rimming - steel through the
ingot route. SMS-II has 2 LD converters, each of 300 T capacity, with suppressed
combustion system and Continuous Casting facility. It produces various Killed
and Semi -Killed steel.

15. FIG. LD CONVERTER
After completion of steel making, it is sent to Continuous Casting Shop (CCS).
This technique entails cooling of steel continuously as it descends down through
the cooling line.
The ladle of steel is poured into Tundish with capacity 25-50 tons and is heated
with propane torched to be fluid. It is then send in mould further encountering
liquid pool and spray cooler.
As it descends down we finally get a slab around a period of 80-90 minutes.
Then solidify at 600∘C.Finally with the help of a torch cutting machine (TCM), re-
quired length of slab is cut. There is another shop where ingot casting is done.

16. RESEARCH AND CONTROL LAB
In this laboratory they check the composition of steel and other materials like
refractories. Also check the steel and pig iron lollypop samples to add or control
the composition of that product. They also test the materials mechanical prop-
erties like tensile strength, compressive strength, fracture defects, toughness,
etc. They have a chart of steels that are used in different area. On basis of these
compositions chart they prepare the required steel for different –different areas
or organization.