The 5800-cubic-meter blast furnace #4 of Jiangsu Shagang Group, at Zhangjiagang plant, in the Lo Jiangsu province, is back in operation after a modernization project executed by Danieli Corus. The project consisted of the conversion of the bosh, belly and lower stack zones to the Danieli Corus high-conductivity lining design, based on a dense pattern of copper plate coolers and graphite refractory. The target of the project was to enable longer furnace campaigns than with the existing lining design, based on stave cooling. A level 2 heat-loss monitoring system was installed to prevent heat losses across eight sections and at three levels to allow for improved process control. The modernized blast furnace –the largest in China– was restarted just over four months after the blow–down, which is an excellent achievement given the scope of the modernization. In line with the project objectives, average shell temperatures have remained below a safe 60 °C. The cooling system has demonstrated its capability to cope with high heat loads, liberating the operator from concerns about furnace integrity under such conditions. Within a few months after commissioning, a coke rate of 326 kg/tHM was achieved, which is a significant 6% lower than before.
