新型小型天然气液化流程

A novel process for small scale liquefaction of natural gas

针对目前零散天然气源回收难、调压站压力能浪费的现状,以及传统天然气液化流程存在系统复杂、混合制冷剂配比困难、能耗大等缺点,基于超声速旋流分离器良好制冷效果这一特点,开展Laval喷管(超声速旋流分离器核心部件)制冷特性和液化分析,提出了一种利用超声速旋流分离器作为核心制冷设备的新型小型天然气液化流程。研究结果表明,Laval喷管具有较节流阀、膨胀机等更好的膨胀制冷效果,且结构简单;天然气在Laval喷管中的液化率整体高于节流阀中。当入口压力为5MPa、温度为300K,利用所提出的液化流程回收压力能时其天然气液化率可达到0.1321。

In view of the current difficulties in recovering scattered natural gas sources and the waste of pressure energy in pressure regulating stations,as well as the shortcomings of traditional natural gas liquefaction processes,such as complex system,difficult mixing of refrigerants and high energy consumption,based on the good refrigeration effect of the supersonic cyclone separator,an analysis on the refrigeration characteristics and liquefaction behavior of the Laval nozzle(a core component of supersonic cyclone separator)are carried out,and a novel small-scale natural gas liquefaction process using supersonic cyclone separator as core refrigeration equipment is proposed.The research results show that Laval nozzle has better expansion and refrigeration effects than throttle valve and expander,and its structure is simple.The liquefaction rate of natural gas in Laval nozzle is generally higher than that in throttle valve.Under the inlet pressure of 5MPa and the temperature of 300K,the liquefaction rate of natural gas can reach 0.1321 when using the proposed liquefaction process to recover the pressure energy.