Steel Making Refractory
Ms Sanghamitra, R&D Refractory Department from TATA STEEL, Jamshedpur, gave a talk on “STEEL MAKING REFRACTORY”, on 12th September 2012 at 11:00 AM at Ceramic Engineering department.
Process chart of TSL, INDIA was first addressed. So, it all starts with iron ores and fluxes (limestone) to be mixed and then pelletized in a sinter plant. At the same time, raw coal is processed to form coke in a coke plant and then sintered pellets along with coke are fed to a blast furnace. Hot metal is obtained at the bottom of the blast furnace above which slag floats, both of them are tapped out. Hot Iron metal is processed in LD1, LD2 and LD3 (Ladles) to lower down the carbon content to form steel, this constitutes the steel making step and the technique is “BASIC OXYGEN STEEL MAKING”. Further, rolling is performed in Merchant mill, New Bar mill, Wire mill, hot strip mill and Cold rolling mill to produce various products- long product and flat product.
There are three major steps/processes involved in steel making: - 1) Primary steelmaking which involves desulphurization, decarburization and de-phosphorization 2) Secondary Steelmaking involving on-line purging of oxygen and processing in Ladle furnace and 3) Continuous casting. All these processes demand specific refractory properties of the containers where various refractories are used. Area of the refractory application is in transfer ladle, basic oxygen furnace/ ladle, steel ladle and tundish.
Transfer ladle is required when hot metal is moved from bottom of blast furnace to other processing units like converter. Refractories essential for transfer ladle are used in four areas- backup lining, barrel, intermediate and bottom. Backup lining needs to be highly insulating so a porous alumina (70% alumina) LCC is employed. Lining which is going to face the hot metal should be acidic to avoid any reaction/corrosion, so Al2O3-SiC-C bricks are used. Intermediate lining is made up of 80% alumina split brick with moderate
Process chart of TSL, INDIA was first addressed. So, it all starts with iron ores and fluxes (limestone) to be mixed and then pelletized in a sinter plant. At the same time, raw coal is processed to form coke in a coke plant and then sintered pellets along with coke are fed to a blast furnace. Hot metal is obtained at the bottom of the blast furnace above which slag floats, both of them are tapped out. Hot Iron metal is processed in LD1, LD2 and LD3 (Ladles) to lower down the carbon content to form steel, this constitutes the steel making step and the technique is “BASIC OXYGEN STEEL MAKING”. Further, rolling is performed in Merchant mill, New Bar mill, Wire mill, hot strip mill and Cold rolling mill to produce various products- long product and flat product.
There are three major steps/processes involved in steel making: - 1) Primary steelmaking which involves desulphurization, decarburization and de-phosphorization 2) Secondary Steelmaking involving on-line purging of oxygen and processing in Ladle furnace and 3) Continuous casting. All these processes demand specific refractory properties of the containers where various refractories are used. Area of the refractory application is in transfer ladle, basic oxygen furnace/ ladle, steel ladle and tundish.
Transfer ladle is required when hot metal is moved from bottom of blast furnace to other processing units like converter. Refractories essential for transfer ladle are used in four areas- backup lining, barrel, intermediate and bottom. Backup lining needs to be highly insulating so a porous alumina (70% alumina) LCC is employed. Lining which is going to face the hot metal should be acidic to avoid any reaction/corrosion, so Al2O3-SiC-C bricks are used. Intermediate lining is made up of 80% alumina split brick with moderate