Influence of heavy hydrocarbons in mixed refrigerant on natural gas liquefaction processes

doi:10.11949/j.issn.0438-1157.20151087

Abstract

Abstract:

Mixed refrigerant(MR)component is one of the most important factors that influence the performance of natural gas liquefaction process.In certain kinds of liquefied natural gas(LNG)plants,heavy hydrocarbons in MR,such as butane and pentane,are not welcome.In this paper,four kinds of MR components have been used in the single mixed refrigerant(SMR)process:MR with both i-butane(C₄)and i-pentane(C₅); MR without C₄; MR without C₅; MR without C₄ and C₅.The specific power consumption has been compared.The results show that compared with i-butane,i-pentane has greater contribution to the decline of power consumption and that the power required in condition 1 is 18% less than that in condition 4.Furthermore,the SMR liquefaction processes with different pre-cooling refrigerants have been proposed.Compared with condition 4,there is a 12% decline in power consumption for the process with propane pre-cooling.

Key words: natural gas, hydrocarbons, simulation, mixed refrigerant, power consumption, liquefaction process

摘要：

混合制冷剂(MR)组分是影响天然气液化流程性能的最重要因素之一。在某些特定的液化天然气(LNG)装置中,丁烷和戊烷等重组分不受欢迎。研究了以下4种混合制冷剂组分用于单混合制冷剂(SMR)流程的效果:含有异丁烷(C₄)和异戊烷(C₅)的MR;不含C₄的MR;不含C₅的MR;不含C₄和C₅的MR。对各流程的比功耗进行了对比。结果表明,相比于异丁烷,异戊烷对降低能耗的贡献更大;另外,工况1的能耗比工况4低18%。更进一步地,提出了采用不同制冷剂进行预冷的SMR流程。对于工况4,采用丙烷预冷的流程能耗可降低12%。

关键词: 天然气, 碳氢化合物, 模拟, 混合制冷剂, 能耗, 液化流程

CLC Number:

TQ026.1

JIA Rong, LIN Wensheng. Influence of heavy hydrocarbons in mixed refrigerant on natural gas liquefaction processes[J]. CIESC Journal, 2015, 66(S2): 379-386.

贾荣, 林文胜. 混合制冷剂中重烃对天然气液化流程的影响[J]. 化工学报, 2015, 66(S2): 379-386.

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