Research on Technical Pathways and Applications for Efficient Utilization of LNG Cold Energy

Abstract

China’s annual LNG imports exceed 100 billion cubic meters, yet the substantial amount of high-grade cold energy released during its regasification remains largely unrecovered at scale, resulting in significant energy waste. The latent heat of LNG vaporization ranges from 820 to 890 kJ/kg, with each ton of cold energy theoretically convertible to approximately 240 kW·h of electricity, indicating considerable recovery potential. To achieve efficient conversion of this low-temperature cold exergy, this study systematically evaluates the technical benefits across seven typical application scenarios—air separation, CO₂ capture, power generation, cold chain logistics, seawater desalination, and cryogenic grinding—based on the principles of temperature matching, cascade utilization, and cold storage for peak shaving. An integrated modular cold energy recovery system combining refrigeration and power generation has been developed for small-scale LNG stations with daily supply capacities below 10 × 10⁴ m 3 /d. Practical results confirm that this system effectively enhances comprehensive energy utilization efficiency, providing technical support for improving energy system performance, reducing carbon emissions across the industrial chain, and advancing the development of zero-carbon ports and green manufacturing systems.