Patent ID: 8418499
Filing Date: 2013-04-16
Classification: F25J

Abstract:
1. A liquefaction system for converting natural gas into liquefied natural gas by using mixed refrigerants, comprising: a compressor for providing a compressed refrigerant stream by compressing the mixed refrigerants; first and second phase separators for separating the compressed refrigerant stream transferred from the compressor into vapor phase and liquid phase refrigerant streams (i.e. vapor and liquid streams); a turbine expander for converting the vapor stream in a superheated state into an expanded-cold refrigerant stream; a plurality of heat exchangers connected by connecting lines to the first and second phase separators, the turbine expander, a natural gas source and a liquefied natural gas tank so as to cool the natural gas by indirect heat exchange with the expanded refrigerant stream provided by the first and second phase separators and the turbine expander; first and second JT valves that provide expanded refrigerant stream by expanding liquid stream from the first and second phase separators, respectively, wherein the expanded refrigerant stream converted to a low temperature by the first and second JT valves is supplied to one of the plurality of heat exchangers connected to the first and second JT valves so as to cool the natural gas by indirect heat exchange, wherein the plurality of heat exchangers includes: wherein the connecting line includes: