Patent ID: 6085546
Filing Date: 2000-07-11
Classification: F25J

Abstract:
A method for converting a fraction of natural gas from a source to liquid natural gas comprising the steps of providing a source of cool, pressurized, clean natural gas, heat exchange equipment, a restrictor, a liquid natural gas collector, an expander, a compressor and a low pressure receiver, splitting said purified natural gas from said source into first and second flow portions, causing said first flow portion to be cooled by said heat exchange equipment, causing said first flow portion to pass through said restrictor into said liquid natural gas collector wherein at least a part of said first flow portion flashes to liquid natural gas, conveying said second flow portion to said expander, expanding said second flow portion to lower the pressure thereof below said pressure of said receiver with resultant lowering of the temperature of said second portion, conveying said cooled second flow portion to said heat exchange equipment as a cooling medium therefor, directing said second flow portion from said heat exchange equipment to said compressor, running said compressor by expander work, raising the pressure of said second flow portion above the pressure of said receiver conducting said second flow portion from said compressor to said receiver.