液-液二氧化碳储能系统的性能分析

Performance Analysis of Liquid-liquid Carbon Dioxide Energy Storage System

随着间歇性可再生能源的普及,储能系统在电网中发挥着关键作用。与空气储能系统相比,二氧化碳储能具有储能密度高、易液化、环境友好等优势。首先建立了一种液-液二氧化碳储能系统,然后利用Aspen Plus仿真软件对其储能过程进行建模分析,揭示了储能压力、释能压力、压缩机进口压力、节流阀压降、压缩机效率及膨胀机效率等参数变化对系统性能的影响。最后,对这种液-液二氧化碳储能系统进行了参数分析,得到系统最优工艺参数。同时对系统进行[火用]分析,得到[火用]损分布,分析讨论了系统产生[火用]损的内部原因。

With the popularization of intermittent renewable energy,energy storage system plays a key role in the power grid.Compared with the air energy storage system,the carbon dioxide one has advantages of higher energy storage density,easy liquefaction,and environmental friendliness.In this paper,a liquid-liquid carbon dioxide energy storage system was established and Aspen Plus simulation software was used to model and analyze energy storage process.The influences from energy-storing pressure,energy-releasing pressure,compressor inlet pressure,throttle valve pressure drop,compressor efficiency,expander efficiency and other parameters on system performance were revealed.Finally,the parameters of this carbon dioxide energy storage system were analyzed to obtain optimal process parameters of the system.In addition,the system was analyzed to obtain Exergy loss distribution and causes thereof.