Steel is an alloy of iron and carbon along with other alloying elements like manganese and chromium. The production of steel involves processing raw materials, coke oven operations, sintering, blast furnace production of pig iron, and conversion of pig iron to steel through basic oxygen furnace or electric arc furnace. The molten steel is then continuously cast into final shapes. Integrated steel plants carry out the entire process while mini mills use electric arc furnaces and scrap steel. Issues facing the steel industry include outdated technology, low productivity, pollution, and shortage of quality raw materials.

2. Steel is an alloy of Iron and Carbon(0.02% - 2.14%) and
alloying materials like Mn,Cr,Ni,W.
Properties of steel like ductility ,tensile strength,
hardness depends on the composition of C and other
alloy elements.
Density varies from 7750 to 8050kg/m3 .
Classification of Steel :
1. Carbon steel
2. Tool steel
3. Alloy steel
4. Stainless steel

3. Process involved in steel manufacturing :
• Raw material processing.
• Coke Oven operations.
• Preparing Sinter mix.
• Blast Furnace.
• Pig Iron to Steel.
• Continuous Casting Plant.

4. RAW MATERIAL PROCESSING:
COAL
IRON ORE LIMESTONE
DOLOMITEMANGANESE ORE QUARTZITE

5. Main functions of the Raw Material Handling
Department :
•Unloading and stacking of raw materials by wagon
triplers.
•Crushing the materials to the required size.
•Maintaining buffer stock.
•Dispatch of processed inputs.

6. COKE OVEN OPERATIONS:
•Coal is heated in the absence of air to form Coke and
the process is known as Carbonization.
•The process takes place in tall, narrow, roofed chambers
called Ovens.
•Specific no of ovens constitute a battery.
•Volatile gases are removed are removed from the coal.
•By products of carbonization are tar , benjol ,
ammonium sulphate and coke oven gas is used as fuel.
•Cooling of the coke is done either by Wet quenching or
Dry quenching.

7. Advantages of using coke over coal :
Coke has higher calorific value than coal.
Coke does not produce smoke on burning. Thus less
pollution.

8. SINTERING PROCESS
Sinter plant mix iron ore fines with other raw
materials(fine powder form ) at high temperature.
It is cut to the required size before charging it to the
furnace.
B.O.F slag is also used in the sinter mix.
Advantages:
Better use of huge quantity of iron ore fines.
Utilizes the solid waste of steel industry.
Improved quality of hot metal.

9. BLAST FURNACE

10. Solid raw materials(coke + sinter mix +iron ore +limestone+
quartzite) are charged from the top and hot air along with coal dust
and fuel is sent through the buttom.
A counter current heat and mass exchange takes place.
Iron is reduced by C and CO at different temperature.
Blast furnace gas is taken out through the top and can be used as a
fuel after cleaning.
Pig Iron with carbon (4-6%) is drained out through the button the
furnace and is carried by a Laddle.
Slag lighter than molten iron is tapped and is used in cement
factory.

11. Reactions inside blast furnace :
O2 (via hot blast air) + 2C => 2CO
CaCO3(Limestone) => CO2 + CaO
Fe2O3(iron ore) + CO => 2FeO + CO2
CO2 + C (from coke) => 2CO
2FeO + CO => CO2 + Fe (to be tapped as hot metal)
CaO + SiO => CaSiO3(Slag)

12. PIG IRON TO STEEL
Pig iron with carbon content (4-6%) is reduced to less
than 2.14% to form Steel.
It has two methods:
1. Basic Oxygen Furnace
2. Electric Arc Furnace

13. ELECTRIC ARC FURNACE
Scrap steel is fed into the
furnace.
The electrodes produce a
arc to melt the steel.
It requires large amount of
electric power.
BASIC OXYGEN FURNACE
Hot molten iron from the
blast furnace is fed along
with scrap steel and
limestone.
Pure oxygen is given by
water cooled lance pipe to
reduce the carbon content.

14. CONTINUOUS CASTING

15. The molten steel from furnace is taken in the laddle
and is poured in the mould which is surrounded by
cooling water jets.
Support rolls are provided to give the alloy a shape.
Blooms and Billets are produced by continuous
casting.
Advantages :
It can be used to produce bloom or billets 24*7.
Less manpower required.

16. INTEGRATED STEEL PLANT VS MINI STEEL
PLANT
Integrated steel
plant starts from
processing raw
materials and ends
in producing
finished products.
Mini steel plants uses
scrap steel and sponge
iron.
Uses electric arc furnace
to produce bloom and
billets.
May also buy semi
finished steel to produce
finished products.

17. Problems in Steel Industry:
1. Lack of modern technology due to low margin of profit.
2. Low productivity because of inefficient working force.
3. Poor labour relations, inefficient management leads to strikes and
heavy losses.
4. Shortage of good quality raw material.
5. Pollution issues.

18. CONCLUSION
Steel industry is going through a period of loss or a very low
margin of profit because of various resons. Some steps can
be taken to overcome this-
Proper training of labour workforce.
Use of modern technologies in production.
Use of cleaner fuels to reduce pollution.
R & D projects must be carried on to develop new ways of
producing steel.

19. REFERENCE :
•General Plant Operations Engineering (STEEL
AUTHORITY OF INDIA LIMITED)
•WIKIPEDIA
•Material science and Engineering,Smith

20. THANK YOU