Live Case Study
According to the 2017 World Steel Association(WSA) report, the steel industry generates between 7 and 9% of direct emissions from the use of fossil fuel. Of all the contents of direct emission, CO2, being the greenhouse gas, is most relevant. Lowering CO2 emission through reduction in coke consumption in blast furnace process is therefore of huge importance for steel plants.
Tata Steel produces steel using the Blast Furnace-LD [BF-LD] route. In blast furnaces, the solid raw material is converted into liquid hot metal using coal and coke as fuel. Coke is prepared from bituminous coals by pyrolysis and produced in-house through carbonization process which cost ~40% of the steelmaking process. It has been found that a 1% reduction in moisture content in coke reduces its consumption in blast furnaces by 3 kg per ton of hot metal. At coke plants, it was a challenge to reduce the coke moisture to ~4%. This project is focused on the reduction of the coke moisture from 4.63% to 4.16% (10% improvement) through the optimization of quenching and other parameters. It resulted in the reduction of CO2 emission by 0.6%, reduction in water consumption by 3.38 MGD, reduction of moisture from 4.63 to 3.78% (18.4% improvement) and a saving of ~$2 million/year.