两种撬装型天然气液化流程的参数比较

设计了两套典型的撬装型天然气液化流程,对流程进行了模拟计算,比较了两者的关键参数,并分析了各换热器中管路换热负荷-温度的分布情况.结果表明:在没有丙烷预冷的前提下,采用N2-CH4膨胀机液化流程优于混合制冷剂液化流程;较大的温差和换热负荷是造成换热器(火用)损失的主要原因;压缩机功耗对比功耗影响很大,应采用多级压缩、级间冷却方式.

Parameter comparison of two small-scale natural gas liquefaction flows in skid-mounted package

Two typical types of small-scale natural gas liquefaction flows in skid-mounted package were designed and calculated simulatively. The key parameters of two flows were compared, and the heat exchange load-temperature distribution rule of the pipelines in heat exchangers were also analysed. The results show that the N2-CH4 expander cycle has advantage over the mixed-refrlgerant eyele on the premise of no propane pre-cooling. More differences in temperature and heat exchange loads are the primary reasons of exergy loss in heat exchangers. The power consumption of compressors is more influential to specific power/ LNG mol,so the mode of multilevel compression and level gap cooling should be adopted.