Abstract:

To improve the energy integration and equipment sharing level of LNG, a conceptual design of natural gas liquefaction system based on large-scale AP-X^TM liquefaction process and integrated gas subcooling technology (GSP) integrated natural gas condensate (NGL) recovery process was proposed. The performance of the multi-stream heat exchanger, the unit power consumption and the recovery rate of ethane were considered as the three of basic characteristics to evaluate process performance. The simulation and analysis results show that the unit power consumption of proposed process is reduced to 0.45 kW·h·(kg LNG)^-1 which is reduced by 6% compared with conventional independent process. Furthermore, recovery rate of ethane is 93% which prove that NGL s efficient separation is achieved. The thermodynamic analysis, exergy analysis and economic analysis prove that the proposed configuration has high thermodynamics performance and economic value. This study can provide guidance for natural gas engineering research and retrofitted design of natural gas liquefaction technology.

Key words: liquefaction, refrigeration cycle, alkane, optimal design, simulation

摘要：

为提高液化天然气能量集成与设备共用水平,提出了一种基于大型AP-X^TM液化流程，综合气体过冷技术（GSP）的集成NGL（天然气凝液）回收工艺的天然气液化系统的概念设计。基于化工流程模拟软件Aspen HYSYS进行模拟和分析，将集成工艺多流股换热器性能、全流程的单位功耗和乙烷回收率作为衡量系统性能的三项指标。模拟和分析的结果表明，集成NGL回收的AP-X^TM液化工艺单位功耗降低至0.45 kW·h·(kg LNG)^-1，较单产系统能耗降低了6%，同时乙烷回收率达到93%，实现了NGL的高效分离。通过热力学分析、?分析和经济性分析得出本设计流程具有较高的性能和经济价值，可为天然气液化工艺的集成设计和技术改造提供指导借鉴。

关键词: 液化, 制冷循环, 烷烃, 优化设计, 模拟