集成超临界二氧化碳储能循环燃煤发电系统热力学分析

Thermodynamic analysis of coal-fired power generation system integrating supercritical carbon dioxide energy storage cycle

为提升燃煤机组运行灵活性,提出了燃煤发电集成超临界二氧化碳(S-CO_(2))储能循环的热力系统,并基于热力学[火用]分析方法,研究了运行参数对系统不可逆损失的影响。研究结果表明:该系统储能效率可达56.14%,S-CO_(2)流量及S-CO_(2)压缩机/透平压比对系统[火用]效率影响较大;当S-CO_(2)流量在50 kg/s至70 kg/s间增大,系统[火用]效率从44.0%增大至61.0%;当压缩机/透平压比在3.0至6.0间增大,系统?效率从27.5%增大至52.5%。本文提出的方法为提升燃煤机组运行灵活性提供了理论参考,并为可再生能源大规模并网提供了思路。

In order to improve the operation flexibility of coal-fired power units,a thermal system of coal-fired power system coupled with supercritical carbon dioxide(S-CO_(2))energy storage cycle is proposed,and the effect of operation parameters on the system irreversible loss is investigated by thermodynamic exergy analysis.The results show that,the energy storage efficiency of the system can reach 56.14%,and the S-CO_(2) flow rate and the S-CO_(2)compressor/turbine pressure ratio have a greater influence on the system exergy efficiency.With the increase of S-CO_(2) flow rate from 50 kg/s to 70 kg/s,the exergy efficiency of the system increases from 44.0% to 61.0%.With the increase of compressor/turbine pressure ratio from 3.0 to 6.0,the exergy efficiency of the system increases from 27.5% to 52.5%.The method proposed provides a theoretical reference for improving the coal-fired power unit operation flexibility,and provides ideas for large-scale grid connection of renewable energy.