基于不同液化方式的液态二氧化碳储能系统研究进展

Research Progress of Liquid Carbon Dioxide Energy Storage System Based on Different Liquefaction Methods

[目的]随着新能源的大规模应用,新能源发电并网面临的挑战不断突显,储能系统的重要性日益上升。二氧化碳储能(Carbon Dioxide Energy Storage,CES)技术是近年来兴起的一种压缩气体储能技术,具有储能密度大、寿命长、系统设计灵活等优势。其中液态二氧化碳储能(Liquid Carbon Dioxide Energy Storage,LCES)技术在系统高压侧和低压侧均采用液相存储二氧化碳,储能密度高、运行稳定性强。[方法]文章首先介绍了LCES系统的运行原理和关键技术指标,指出二氧化碳液化的重要性和常见工艺。然后介绍了针对LCES系统低压侧CO_(2)液化的研究现状,包括采用混合储能工质、自冷凝、利用LNG冷能、采用蓄冷器,详细分析了各种方式的特点。[结果]研究表明,采用蓄冷器是最具优势的方式。进一步分析蓄冷液化面临的技术挑战及发展前景具有必要性。[结论]研究为LCES系统CO_(2)液化技术的进一步发展提供了指导。

[Introduction]With the large-scale application of new energy,the challenges faced by the grid connection of new energy power generation are growing,and the importance of energy storage system is increasing.carbon dioxide energy storage(CES)technology is a kind of compressed gas energy storage technology emerging in recent years,with the advantages of high energy storage density, long service life and high design flexibility. For liquid carbon dioxide energy storage (LCES) technology, CO2 is stored as liquid phase in both HP and LP sides of the system, which has high energy storage density and strong operation stability. [Method] Firstly, the operation principle and key technical indicators of the LCES system was introduced and the importance of carbon dioxide liquefaction and common liquefaction processes were clarified. Then, the research status of CO2 liquefaction on the LP side of the LCES system was introduced, including the use of mixed energy storage working medium, self-condensation, the LNG cold energy, and the regenerator. The characteristics of each method were analyzed in detail. [Result] The research indicates that the application of regenerator is the most effective method. It is necessary to further analyze the challenges faced by current cold storage liquefaction technology and its development direction. [Conclusion] The research could provide guidance for the further development of CO2 liquefaction technology for the LCES system.