NEW DELHI: The National Green Tribunal (NGT) has directed the Central Pollution Control Board (CPCB) to respond within a month to a report by IIT-Kharagpur which has raised grave environmental concerns over the use of coal-based rotary kiln technology in steel manufacturing.
IIT-Kharagpur submitted a report to the NGT, recommending the complete phasing out of small to medium and lower capacity coal-based sponge iron or Direct Reduced Iron (DRI) plants. These plants are primarily concentrated in Jharkhand, Odisha, West Bengal, Chhattisgarh, Andhra Pradesh, Telangana, and Tamil Nadu.
This recommendation aims to mitigate carbon emissions. The report suggests that the government should not grant any environmental clearance to such units. The DRI process is highly energy-intensive, using coal to remove impurities and produce sponge iron. It is called ‘sponge’ because the removal of oxygen creates tiny holes, giving it a spongy appearance under a microscope.
In addition, the report. titled “Decarbonizing Coal-based Rotary Kiln Steel Sector in India” advises providing support to larger plants with capacities exceeding 500 tonnes per day (tpd). These plants are more efficient and can be improved further through retrofitting with new technology.
The IIT prepared this report in response to environmental concerns raised by the NGT regarding coal-based rotary kiln technology used in steel manufacturing. Following the report, the NGT directed the CPCB to respond within one month.
Currently, smaller DRI plants lead to carbon emissions at a rate of 4.1 tonnes of CO2 per tonne of sponge iron, as compared to the global average of 1.9 tonnes of CO2 per tonne. This situation challenges India’s efforts to meet the goals set by the Paris Agreement in 2015 to curb global warming.
The report indicates that there is limited potential to enhance the capacity and efficiency of these smaller plants. “This is a critical time for India to ban granting environmental clearance to any new (greenfield) or existing (brownfield) coal-based sponge iron production through rotary kilns, as these processes are carbon-intensive, visibly polluting, and pose serious health risks to both workers and surrounding communities,” the report says.
It recommends the government establish short-term, medium-term, and long-term goals for these DRI plants to reduce CO2 emissions and enhance their sustainability. It also suggests installation of Waste Heat Recovery plants and tech interventions to curb pollution.