余热动力利用中多点排放余热源换热网络的优化

OPTIMIZATION OF WASTE-HEAT SOURCE HEAT EXCHANGER NETWORK

根据所设计的余热源换热器网络的物理模型,以(火用)损失最小为目标函数,导出了换热网络的优化数学模型。采用序贯无约束极小化(SUMT)方法,获得了优化数值解和工程解。实例表明,与未优化的实际方案相比,优化换热网络的热效率、(火用)效率分别提高33.3%和21.7%。当采用双级热水扩容法回收动力时,优化换热网络的动力回收系统的(火用)效率提高10.9%。

According to the designed physical model of waste-heat source heat exchanger network, and taking the minimum loss of exergy as the objective function, the optimized mathematic model of the heat ex- changer network is derived. Using sequential unconstrained minimization technique (SUMT), the op- timal numerical soution and optimal engineering solution are obtained. The calculation for a real in- stallation shows that as compared with non-optimized solution, the thermal efficiency and exergy effi- ciency of the optimized network increase 33. 3% and 21. 7% respectively. When using two-stage vol- ume expansion method to recover power, the exergy efficiency of the optimized network power recov- ery system increases 10. 9%.