天然气液化技术研究现状及进展

Natural gas liquefaction technology research status and progress

系统的阐述了国内外关于天然气液化流程的研究成果,着重介绍了一种新型天然气液化技术。目前国外较大型LNG工程主要采用级联式液化流程及混合制冷剂液化流程,且已开展小型天然气液化装置的研究,并已开发了几种小型的天然气液化装置,但其液化流程主要是由大型装置演化而来,并未出现本质变化;国内LNG液化工艺流程研究起步较晚,且由于天然气气源和LNG目标市场的限制,目前投产及在建装置均属于小型天然气液化装置,国内所利用小型天然气液化流程主要为膨胀制冷循环及混合制冷剂循环。超声速旋流分离器被提出应用于天然气液化过程,目前研究表明,其能成功将天然气液化,但关于超声速旋流分离器内部天然气流动过程、液滴凝结及生长热力学过程、液化效率等还需开展进一步的研究工作。

Natural gas liquefaction processes at home and abroad were elaborated systematically, and a new natural gas liquefaction technology was introduced emphatically. At present, cascade liquefaction process and mixed refrigerant liquefaction process were mainly used in foreign larger LNG liquefaction projects. Some research about small-scale liquefaction device had been carried out, and several devices had been developed, but the liquefaction processes of small-scale devices were mainly evolved from large-scale devices. Domestic LNG liquefaction process research started late, and the production and under construction devices were all small-scale devices due to the restriction of natural gas source and LNG market. The process mainly used in domestic small-scale devices was expansion refrigeration cycle and mixed refrigerant cycle. Supersonic swirling separator used in natural gas liquefaction process had been proposed, and the present study showed that the natural gas could be liquefied successfully by this technology. But more research was needed on the gas flow, droplet condensation and growth thermodynamic process in the separator as well as its liquefaction efficiency.