JSW Projects Ltd., a subsidiary of JSW Steel Ltd., has installed a COREX® gas-based MIDREX® direct reduction plant at their Vijayanagar plant in Toranagallu, Karnataka, India. This facility, engineered by Primetals Technologies Ltd. in partnership with Linde AG and Midrex Technologies, Inc., has a production capacity of 1.2 million tons of direct-reduced iron (DRI) per year. Featuring a hot DRI transport system to the adjacent electric arc furnace (EAF) plant, the plant efficiently utilizes COREX® export gas to meet India's rising steel demand.
Challenge
JSW Steel aimed to sustainably increase iron production to meet India's rising demand while maintaining their leading environmental standards. Traditionally, COREX® export gas from two COREX® C-2000 modules—each with a nominal capacity of approx. 800,000 tons of hot metal per year—was utilized primarily for power generation. The goal was to repurpose this valuable gas for direct reduction to produce additional iron, which required innovative engineering solutions. The project demanded precise handling of complex processes to transform COREX® export gas as well as coke oven gas into a viable energy source, ensuring high metallization levels and operational efficiency in an isolated area with limited fuel access.
Solution
The solution entailed a comprehensive approach to utilizing COREX® export gas for direct reduction. This involved cleaning, compressing, and treating the gas in a pressure swing absorption system to remove CO2, followed by heating in two stages to achieve the desired reducing gas temperature. The heated gas was introduced into the shaft furnace's reduction zone, flowing counter-currently to the descending iron oxide material, operating at approximately 800°C. The plant achieved metallization levels of 92% or higher, aided by a hot transport system that conveyed HDRI to the adjacent EAF, improving energy efficiency and productivity. The project's scope included the supply of key equipment, electrics and automation systems, supervision of erection, commissioning, start-up, and training services, ensuring a seamless integration of new technologies and processes.
Results
The COREX® gas-based MIDREX® direct reduction plant has delivered significant operational improvements. The plant achieved a high metallization level of 92%-94%, with a nominal capacity of 147 tons per hour. The hot DRI transport system increased productivity by 15%-20% and reduced power consumption by 130-150 kWh per ton of liquid steel. Electrode savings reached 0.5-0.6 kg per ton, underscoring cost efficiency.
Benefits
Safe and clean ironmaking utilizing COREX® export gas
- Maximized COREX® export gas utilization for DRI production
- Utilization of tail gas, DR bypass-gas, and DR off-gas for heating and power generation at the downstream steel plant
- Increased productivity by 15%-20% due to the hot DRI transport system to the electric arc furnace (EAF)
- Power savings of 130-150 kWh per ton of liquid steel in the electric arc furnace (EAF)
- Electrode savings of 0.5-0.6 kg per ton of liquid steel in the electric arc furnace (EAF)
Conclusion
The MIDREX® direct reduction plant at JSW in Toranagallu, India, exemplifies cutting-edge technology in steel production, with an annual output of 1.2 million tons of DRI.
- It effectively uses COREX® export gas, advancing JSW's zero-effluent-discharge goals and enhancing sustainability.
- The hot DRI transport system boosts productivity and cuts power usage, enhancing overall efficiency.
- Electrode savings contribute to cost efficiency and resource conservation.
- The partnership between Primetals Technologies Ltd., Linde AG, and Midrex Technologies Ltd. highlights innovative advancements in sustainable steel production.
