SINGLE MIXED REFRIGERANT GAS LIQUEFACTION PROCESS

摘要

A method of gas liquefaction wherein the refrigeration to cool and liquefy an essentially water-free feed gas is provided by a single recirculating mixed refrigerant cycle in which refrigeration is provided by the vaporization of two mixed refrigerant streams of different compositions at a lower and higher pressure levels respectively. A lower pressure level vaporizing refrigerant cools the feed gas stream in a first cooling zone and a higher pressure level vaporizing refrigerant further cools and condenses the cooled gas in a second cooling zone to provide the final liquid product. The lower pressure level vaporizing refrigerant is provided by one or more liquids obtained by ambient cooling of compressed mixed refrigerant vapor. The vaporized lower pressure level refrigerant can be returned to the refrigerant compressor at a temperature below ambient, without further warming, and this cool refrigerant is compressed an d combined with the vaporized higher pressure level refrigerant, which is returned at about ambient temperature.