What are the different manufacturing processes in the production of steel?

Steel has played a vital role in the development of modern human civilization. Steel plays a significant role especially in the development of developing economy. Per capita consumption of steel is used as an indicator of socio economic development of the country as well as an indicator of standard of living of its people. Economic growth of India depends upon the growth of the Indian steel industry. Steel continues to be used in traditional sectors such as construction, housing and ground transportation, special steels has been increasingly used in engineering industries such as power generation, petrochemicals and fertilizers (Planning Commission, 2009). Currently, India is the 4th largest producer of crude steel in the world and is expected to become the 2nd largest producer of crude steel soon. The steel sector of India employs over six lakh of people & contributes nearly 2%in the country’s GDP. The different manufacturing process in the production of steel are as follows:

1. Blast furnace/basic oxygen furnace (BF/BOF) :Iron ore is converted into liquid form of Iron by BF but Iron produced by BF has high carbon content and other impurities, this iron is called pig iron. Because of its high carbon content, Pig iron has limited end user applications. To make steel products out of pig iron The Basic oxygen furnace is used for producing steel from the refined iron and the carbon contents and other impurities are removed through slag separation. At present around 67% of the world steel is produced through BF/BOF route. This route is very good for volume production.Iron ore and coal/coke are used in BF as main inputs. It is also called oxygen furnace because oxygen is the only fuel used in the process. But the process requires high capital cost and substantial investments on infrastructure. Producers that use blast furnace technology are SAIL, RINL, TSL and JSWL.

2. Electric Arc Furnace: Steel scrap orPig iron or Sponge iron is used as the raw material in this process.Basic purpose of the EAF is re-melting sponge iron, steel scrap, and pig iron. At present around 31% of world steel is produced by this process. It uses electricity as much as 400-500 kWh/ton. EAF is an environment friendly process and has flexibility to produce variety of value added grades of steel. ISPAT, ESSAR, and the Jindal group are examples of producers, who use this technology.

3. COREX or Cipcor Process COREX is an advance process of producing steel. The process is used by a few only. Non-coking coal can directly be used in smelting work and lumpore and pellets are used as inputs in this process. With These two advantages steel producers can eliminated coking plants and sinter plants. Coking plant converts non-coking coal into more efficient fuel and sinter plant purify lump ore or pellets for further processing. Basic inputs to COREX are iron-ore and coal. COREX technology is used by Jindal Iron & Steel Company to produce finished steel.

4. Induction Arc Furnace (IAF) IAF isone of the most advance processes of steel making. IAF use selectricity as its main fuel. IAF is the most environment friendly steel making process and one of the most efficient ways of producing steel designing course in kochi. But IAF requires clean products as its inputs as it lacks refining capacity. A lot small steel companies use IAF technology.The weight of the product significantly pushes up transport and movement costs. Therefore large steel plants are the norm for cost efficient production and for specialized steel and alloys efficient production by smaller plants is possible.