高炉渣固定床显热回收过程火用分析及系统优化设计

为使高炉渣显热得到高效高品质的回收,对固定床渣热回收过程进行火用分析,分析该过程主要不可逆因素(温差、流动阻力)产生的火用损;揭示颗粒直径、空隙率、床层高度、表观气速和空气初始温度等因素对总火用损率的影响规律。研究表明,随颗粒直径和床层高度的增大,总火用损存在一个最小值,对应存在颗粒直径和床层高度最优值;表观气速越大,总火用损越大;空隙率越大,总火用损越小;空气入口温度存在最佳值,并非越低越好。

Exergy analysis and system optimization design for sensible heat recovery of blast furnace slag in fixed-bed

A thermodynamic analysis through energy and exergy is employed to investigate exergy losses of the irreversibility caused by heat transfer and air flow in the process of sensible heat recovery of blast furnace slag(BFS) in fixed-bed((FB).And a comprehensive numerrical study is performed to reveal the influence of particle diameter,bed voidage,bed height,superficial air velocity and air inlet temperature to total exergy losses.The results show that total exergy loss increased at the beginning and decreased at last with particle diameter and bed height,while decreased with bed voidage and increased with superficial air velocity.In tradition view,air inlet temperature is the lower the better,but the results demonstrate that there is a optimal value of air inlet temperature.