COREX CGD预还原竖炉内煤气停留时间分布的数值模拟

Numerical simulation of the residence time distribution of COREX shaft furnace with CGD

文章利用数值模拟方法研究了COREX预还原竖炉内煤气停留时间分布(RTD)特性,分析了CGD (central gas distribution)装置对炉内煤气RTD分布特性的影响,并对不同熔炼率下炉内煤气RTD规律进行了研究。模拟结果表明,安装CGD后,增加了竖炉底部中心供气,提高了煤气平均停留时间。此外,CGD的安装降低了炉内平均停留时间的无量纲方差,且有效减少了炉内死区体积分数,有利于炉内气固相间的还原反应及传质、传热。随着熔炼率增加,炉内煤气平均停留时间缩短,死区体积分数减小。

The numerical simulation method was used to investigate the residence time distribution(RTD)of reducing gas in COREX shaft furnace with central gas distribution device(CGD),including the effect of CGD and hot metal productivity on the RTD distribution characteristics.The results reveal that the CGD installment improves the central gas distribution at the bottom of the furnace and increases the residence time of reducing gas.In addition,the CGD installment decreases the dimensionless variance and reduces the dead volume fraction in the furnace,which was beneficial for the chemical reactions and transfers of heat and mass between the gas and solid phases.With the hot metal productivity increasing,the residence time was reduced and the dead volume fraction was decreased.