Abstract: In order to increase the utilization rate of cold energy in LNG terminal and maximize economic, social and environmental benefits in engineering, it is necessary to analyze the process efficiency of different cold energy utilization schemes and propose feasible process schemes. Based on the actual project of a large domestic LNG terminal, C₂H₆, C₂H₂F₂, CClF₃, CHF₃, C₂F₆, CF₄ and CH₄ are selected for comparison calculation, and C₂F₆ is selected as the circulating working fluid of the cold energy utilization power generation system of the LNG terminal, calcium chloride solution is selected as the secondary refrigerant. Using organic Rankine cycle low-temperature power generation technology and 30% (mass concentration) CaCl₂ solution external cold transfer method, the full power generation process scheme and partial power generation process scheme are compared. The net power generation and cooling capacity of full power generation process scheme are greater than that of partial power generation process scheme, which can generate greater economic benefits.

Key words: LNG terminal, combined cooling and power generation process, organic Rankine cycle, secondary refrigerant, organic working fluid

摘要： 为提高液化天然气(LNG)接收站冷能利用率,实现经济效益、社会效益和环境效益最大化,对不同冷能利用方案的工艺效率进行分析并提出可行的工艺方案。结合国内某大型LNG接收站的工程实际,选取C₂H₆,C₂H₂F₂,CClF₃,CHF₃,C₂F₆,CF₄和CH₄作为工质进行模拟计算,最终选用C₂F₆作为循环工质,并选择氯化钙溶液作为载冷剂。采用有机朗肯循环低温发电技术和30%(质量分数)氯化钙溶液外输冷量相结合的方式,对满发电和部分发电工艺方案进行对比研究,发现采用满发电工艺方案的净发电量和制冷量大于部分发电工艺方案,能够产生更大的经济效益。

关键词: LNG接收站, 冷电联产工艺, 有机朗肯循环, 载冷剂, 有机工质