| abstract |
A system and method for liquefying a natural gas stream, the method including the steps of providing a dehydrated natural gas stream for liquefaction (100), pre-cooling the dehydrated natural gas stream in a pre-cooling apparatus (101), where the pre-cooling is performed by using a pre-coolant (162) that consists essentially of a hydrofluorocarbon (HFC) refrigerant, and further cooling the pre-cooled dehydrated natural gas stream (114) in a main heat exchanger (115) through indirect heat exchange against a vaporized hydrocarbon mixed refrigerant coolant (130) to produce a liquefied natural gas product stream (116), where the mixed refrigerant coolant comprises ethane, methane, nitrogen, and, preferably, less than or equal to 3 mol % of propane. |