Alternative pre-cooling arrangement

摘要

A natural gas liquefaction system, the system comprising a first precooling refrigeration system (106) that accepts at least a natural gas feed stream (102), a second precooling refrigeration system (108) that accepts at least a first refrigerant stream (104); and a cryogenic heat exchanger (146) fluidly connected to the first precooling refrigeration system and the second precooling refrigeration system that accepts the natural gas feed stream (150) from the first precooling refrigeration system and the first refrigerant stream (138) from the second precooling refrigeration system to liquefy the natural gas feed stream (166), where the second precooling refrigeration system accepts only stream(s) having a composition different from the stream(s) accepted by the first precooling refrigeration system.