利用燃气轮机烟气余热的复合有机朗肯循环系统优化分析

Optimization and Analyses of an Organic Rankine Cycle Combined System Utilizing the Waste Heat of Gas Turbine Exhaust

本文针对燃气轮机烟气余热设计了一种复合有机朗肯循环系统,对其进行了详细的热力学分析,以某燃驱压气站烟气条件(400℃,26 kg/s)为例,以系统净输出功为目标,利用Matlab和Refprop 9. 0选择了13种工质,并确定了系统最优工况。结果表明,甲苯、R141b、丙酮分别作为3个子系统的工质时,系统可实现最大净输出功为1 587 k W,热效率和火用效率分别可达20. 26%和42. 68%,比单级循环可实现的最大净输出功高23. 33%。对系统各部件进行[火用]损失分析,发现蒸发器[火用]损失最大,并提出了改进方案。

In this study a combined organic Rankine cycle system is proposed to utilize the waste heat of gas turbine exhaust.The thermodynamic properties of the system are analyzed in detail.Taking an engine-driven gas compressor station as an example,13 working fluids were compared and the parameters were determined to maximize the net output work using MATLAB and REFPROP 9.0.The results show that when toluene,R141b,and acetone are selected as the working fluids of the three subsystems,the system can achieve a maximum net output power of 1587 kW,thermal efficiency of 20.26%,and exergy efficiency of 42.68%.The maximum net output work is 23.33%higher than that of a single-stage cycle.The exergy loss of components is analyzed and it is concentrated in the evaporator,based on which an improvement scheme is proposed.