基于(火用)效率目标的环冷机余热回收系统操作参数优化

摘要：针对烧结环冷机余热回收利用率不高的难题，采用分析法建立了评价某钢铁厂烧结环冷机余热回收系统运行效率的效率模型。基于多孔介质模型、局部非热平衡方程、真实气体SRK方程建立环冷机内气固两相换热模型。通过CFD仿真模拟，探究料层高度、循环风机输入烟气温度、烧结矿底部入口风速三项可控环冷机运行工艺参数对系统效率的影响规律。结果表明，料层厚度在1～1.5 m区间每增加0.1 m，效率增加0.8%～1.1%；循环风温在100～140℃之间每增加10℃，效率增加1.4%～1.5%；烧结矿底部入口风速在0.9～1.9 m/s之间每增加0.1 m/s，效率降低0.18%～0.24%。在此基础上，基于工业运行数据建立效率正交试验优化模型，提高了该余热回收系统3.42%的效率。

Research on operation parameters optimization of sinter cooler waste heat recovery system based on exergy efficiency optimization

Aiming at problem of low recovery rate of residual heat of sintering ring cooler, the exergy analysis method was used to establish the exergy efficiency model for evaluating the operating efficiency of the waste heat recovery system of a sintered ring cooler in a steel plant. Based on porous medium model, local non thermal equilibrium equation and real gas SRK equation, the gas solid two phase heat transfer model in the ring cooler was established. Through the CFD simulation, the influence law of the operating parameters of the three controllable ring coolers on the exergy efficiency of the layer height, cooling gas temperature and inlet gas speed were investigated, the results show that the exergy efficiency increases by 0.8%-1.1% for each 0.1m increase in layer height from 1 m to 1.5 m, efficiency increases by 1.4%-1.5% for every 10℃ increase in gas temperature between 100℃ and 140℃ and increases by 0.18%-0.24% for every 0.1m/s increase in gas speed between 0.9m/s and 1.9m/s. On this basis, bases on the industrial operation data, the orthogonal experiment optimization model of enthalpy efficiency is established, which improves the exergy efficiency of the residual heat recovery system by 3.42%.