C3/MRC液化流程中原料气成分及制冷剂组分匹配  

Analysis for interrelations between mixed refrigerant composition and raw natural gas in C3/MRC liquefaction cycle

作　　者：赵敏[1] 厉彦忠[1] 

机构地区：[1]西安交通大学能源与动力工程学院,陕西西安710049

出　　处：《化工学报》2009年第S1期50-57,共8页CIESC Journal

基　　金：国家自然科学基金项目(50676074)~~

摘　　要：针对两种代表性原料天然气No.1和No.2,利用AspenHYSYS流程模拟软件对C3/MRC天然气液化流程进行了动态模拟,考虑了混合制冷剂高低压变化、混合制冷剂组分改变,通过模拟研究获得了混合制冷剂各个组分N2、CH4、C2H6及C3H8在制冷系统中的不同作用,同时获得了制冷剂组分与混合制冷剂高低压以及原料天然气cp-T之间的依赖关系,全面动态地展示了制冷剂各组分在C3/MRC流程中的影响和作用。在此基础上,又对比了原料天然气No.1和No.2在不同混合制冷剂高低压下C3/MRC流程的能耗指标。研究结果表明:原料天然气的cp-T关系是决定整个C3/MRC流程能耗高低的关键因素,而混合制冷剂的组分或高低压的选择则对系统能耗影响较弱。混合制冷剂的组成及其高低压力的选择应根据原料天然气的cp-T关系进行合理选取,以确保流程设计更为合理。The propane mixed refrigerant cycle(C3/MRC)is the most cost-effective and reliable base-load LNG process.In this paper,two kinds of representative raw natural gases No.1 and No.2 are chosen to study this cycle by using Aspen HYSYS process simulation software,taking into account changes in the cyclic pressures and compositions of mixed refrigerant.Through the research,the functions of mixed refrigerant component N2,CH4,C2H6,and C3H8 in the refrigeration for C3/MRC cycle,are obtained.More importantly,the interrelations between mixed refrigerant composition and raw natural gas's specific heat vs temperature(cp-T)property,as well as the mixed refrigerant cyclic pressures,are also obtained,thus fully demonstrating the refrigeration functions of mixed refrigerant components in the cycle.On the above basis,the energy consumptions of C3/MRC cycle are compared between the natural gases No.1 and No.2 under different cyclic pressures of mixed refrigerant condition.The results show that the cp-T property of raw natural gas is the dominant factor to determine the level of the whole cycle's energy consumption,while the mixed refrigerant composition and cyclic pressures are secondary factors relatively,which should be selected appropriately in terms of the cp-T of raw natural gas to make the cycle design more reasonable.

关 键 词：C3/MRC天然气液化流程 原料天然气 混合制冷剂组分 

分 类 号：TE646[石油与天然气工程—油气加工工程]