Dual mixed refrigerant cycle for gas liquefaction

摘要

Process and system for liquefying a pressurized gas, especially natural gas. The process is carried out in two heat exchangers, and cooling for each heat exchanger is provided by a mixed refrigerant which is vaporized at a single essentially constant pressure. Feed precooling, low level refrigerant precooling, and high level liquid refrigerant subcooling are effected in one of the heat exchanger against low level refrigerant vaporizing at a single essentially constant pressure. The process and system of the invention are especially well-suited for installation on ships, barges, and offshore platforms.