Study on a novel liquid air energy storage system integrated with two-column air separation unit

The liquid air energy storage (LAES) system offers advantages such as high energy density and strong flexibility and is often coupled with external energy sources or processes to enhance its applicability. This paper proposes a novel LAES system integrating with a two-column cryogenic air separation unit (ASU). During the charging phase, the gaseous products from the separation tank of LAES are used to supply the ASU with feedstock, while the stored liquid air provides cooling to the ASU. Additionally, external air is supplied to compensate for the shortage of oxygen in the feedstock. During the discharging phase, the ASU operates solely through the supplementary air supply, reducing the system's power consumption. This study analyzes the operational characteristics of the coupled LAES-ASU system and discusses the effect of liquid air supply of LAES to the ASU on the system performance.