ENHANCEMENT OF IRON ORE SINTERING THROUGH COAL GAS INJECTIONDhanraj Patil1
1JSW Steel Pvt. Ltd., Toranagallu, IndiaPAPER: 76/Iron/Regular (Oral) OS
SCHEDULED: 15:05/Wed. 19 Nov. 2025/Lotus
ABSTRACT:The present study introduces an industrial-scale innovation for intensifying the iron ore sintering process through coal gas injection via a waste gas recirculation system. Coal gas, a byproduct generated during the coking process in coke ovens, is rich in combustible components such as hydrogen, methane, and carbon monoxide. Coal gas, injected into the upper layer of the sinter bed through a specially designed pipeline and nozzle arrangement within the recirculation hood, promotes a more uniform combustion front, enhances high-temperature retention, and improves heat transfer across the sintering bed.
The process has been successfully implemented at the plant level and has shown clear operational benefits. Key improvements include a 5–10% increase in the yield of coarse sinter (+10 mm), a 1–2% reduction in fine particles (−5 mm), and a 1–2% gain in sinter mechanical strength. The mean sinter particle size also increased by several millimeters, contributing to better handling and blast furnace performance. Furthermore, solid fuel (coke) consumption was reduced by 3–5% per ton of sinter produced, demonstrating significant potential for energy savings.
By partially substituting coke with cleaner-burning coal gas, the process also contributes to lower carbon emissions and reduced environmental impact. These improvements underscore the dual benefits of this technique: enhancing product quality and operational efficiency while supporting sustainability goals. Overall, coal gas injection through the waste gas recirculation system offers a robust, scalable, and cost-effective upgrade for integrated steel plant sintering operations.
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