Research Progress and Prospects for LNG Cold-Energy Cascade Utilization

Under the backdrop of the "dual carbon" strategy， the efficient cascade utilization of liquefied natural gas （LNG） cold energy plays a critical role in facilitating the low-carbon transition of the energy structure and promoting resource recycling. This study systematically reviews the technological progress， application scenarios， and future challenges. Based on a technology maturity assessment framework， comprehensive cold-energy utilization schemes used in different scenarios are proposed. Current research indicates that the cold energy released during LNG regasification can be efficiently recovered through cascade utilization across three temperature ranges， i.e.， deep cryogenic （-162 ℃ to -100 ℃）， mid-cryogenic （-100 ℃ to -50 ℃）， and low cryogenic （-50 ℃ to 0 ℃）. Current mainstream technologies include cold-energy power generation， air separation， freezing/cold storage， and CO2 capture. Among these， air separation has the highest maturity （TRL9）， with large-scale applications achieved in multiple domestic receiving terminals. Cold-energy power generation （TRL8） has significantly improved the efficiency through combined cycle optimization； however， the challenges remain in terms of the system complexity and stability. It is found that the LNG cold-energy utilization rate in China is generally low and is primarily constrained by significant volatility， an uneven spatiotemporal distribution， weak process coupling， and insufficient industrial chain coordination. Future efforts should be focused on three key directions： optimizing the construction layout by establishing the industrial parks for onsite cold-energy consumption， constructing a comprehensive evaluation system to promote the efficient cascade utilization of cold energy with multimode collaboration， and enhancing the flexibility and stability of cold-energy utilization by developing energy-storage systems. This study provides recommendations and guidances for the technological optimization and industrial development of LNG cold-energy cascade utilization.