基于循环拆分法的S-CO_(2)燃煤发电优化研究

Optimization Study of S-CO_(2) Coal-fired Power Generation Based on Cycle Splitting Method

对于S-CO_(2)燃煤发电系统,系统复杂难以横向比较,拆分法通过对循环流量分配,能够梳理循环回热过程并进行循环间的比较,应用循环拆分法有助于对复杂燃煤发电系统的性能进行分析。本文以再压缩循环(RC)为例,构建了集成冷却器热量回收(CHR)和烟气冷却器法(FGC)的S-CO_(2)燃煤发电系统(RC+LFGC+CHR),论证了拆分法在分析燃煤发电系统中的优势。当主气参数为620℃/28 MPa时,应用拆分法分析,RC+FGC+CHR可等效为在热效率49.21%的RC基础上,叠加热效率为57.49%的子循环(SSC+LFGC+CHR),故RC+FGC+CHR效率(49.80%)高于RC(49.21%)。

For the S-CO_(2) coal-fired power generation system,the system is complex and difficult to compare horizontally.The cycle splitting method is able to sort out the cycle heat recovery process and compare between cycles by distributing the cycle flow rate,and the application of the cycle splitting method helps to analyze the performance of the complex coal-fired power generation system.In this paper,the S-CO_(2) coal-fired power generation system(RC+LFGC+CHR)with integrated cooler heat recovery(CHR)and flue gas cooler method(FGC)is constructed with recompression cycle(RC)as an example,and the advantages of the cycle splitting method in analyzing coal-fired power generation systems are demonstrated.When the main gas parameter is 620℃/28 MPa,applying the splitting method to analyze,RC+FGC+CHR can be equated to a subcycle(SSC+LFGC+CHR)with a thermal efficiency of 57.49%overlapped on top of the RC with a thermal efficiency of 49.21%,so the efficiency of RC+FGC+CHR(49.80%)is higher than that of RC(49.21%).