Adoption of Heat Recovery Technology in Sintering Process to Reduce Carbon Imprint

Abstract

India is the second largest steel producer in the world after China. The 2017 National Steel Policy of India set out the ambitious plan of 250 MT steel production and per capita consumption to around 160 kg by 2030. The dominant iron-making route is blast furnace (BF), which is an energy-intensive process based on fossil fuel consumption. The steel industry contributes around 7% of all greenhouse gas (GHG) emissions. India pledged to reach net zero by 2070 at COP26 in Glasgow. In an integrated steel plant, approximately 6.0 Gcal heat energy is required for production of 1 tcs. In sintering process, an ample amount of heat energy is discharged to the atmosphere through cooler exhaust gases as well as flue gases (around 55% of total heat input). Sinter cooler exhaust gases have temperature in the range of 250–400°C. Research has been carried out to utilize sensible heat of these waste hot gases in progressive manner. Several technologies have been established for utilization of hot waste gases from sinter plant which reduces emission of harmful gases to the environment by drastically reducing the burning of coke. To utilize waste heat from sinter cooler for producing hot water, a system named, “Waste Heat Recovery System (WHRS)” was conceptualized, designed, installed and commissioned at machine#1 of SP-3, Bhilai Steel Plant (BSP). The paper illustrates the entire process of WHRS and its role in reducing overall energy consumption of sinter plant.