含空气净化过程的液态空气储能热力学研究

Thermodynamic study of liquid air energy storage with air purification unit

针对现今液态空气储能(LAES)研究中普遍存在忽略空气净化过程能耗而使LAES系统能效被高估的问题,提出了一种含空气净化过程的LAES系统。该系统包含空气液化过程、液态空气释能过程和TSA纯化过程,通过全流程的仿真模拟验证系统可行性,并对其进行热力学分析。结果显示:提高液态空气释能压力、空气透平进口温度和储热油使用比例,可以有效提升系统的热力学性能;储存的压缩热仍有约36%未被完全使用,若将其全部回收利用,全系统效率可达0.623;该含空气纯化过程的LAES系统储电效率为0.471,比基线LAES系统低6.8%。

In the current research on liquid air energy storage(LAES),it is found that the performance of LAES system is generally overestimated without considering the power consumption of air purification.This paper therefore proposes a complete LAES system with air purification unit.The LAES system consists of three parts:charging cycle,discharging cycle and TSA process.The whole system is verified to be feasible by the simulation in the Aspen Plus? version 8.4,and the thermodynamic analysis of this system is carried out.The results show that the thermodynamic performance of the system can be effectively improved by increasing the discharging pressure,the air turbine inlet temperature and the proportion of the thermal oil used in the discharging cycle.About 36%of the stored heat of compression is not fully used,if it is totally recycled,the exergy efficiency of the whole system can reach 0.623.The electricity storage efficiency of the LAES system with air purification unit is 0.471,which is 6.8%lower than that of the baseline LAES system.