PROCEDURE FOR NITROGEN LICUEFACTION THROUGH COLD RECOVERY DERIVED FROM LIQUID GASIFICATION.

摘要

Process for liquefaction of a cryogenic fluid by recovering the cold derived from the gasification of liquid methane, which comprises the stages of cooling (4) with the liquid methane (1) of a first cryogenic fluid (5), preferably nitrogen, and the subsequent use of said first cryogenic fluid as a cooling fluid in a first compressor unit (22-23-24-25-26), both for intermediate refrigerators (28, 29, 30, 31) and for intake and supply refrigerators end (27, 32) of said first compressor unit, the cryogenic fluid (3) being compressed by the first compressor unit (22-23-24-25-26) and liquefied in a heat exchanger (19), characterized in that the exchanger of heat is cooled by another separate cryogenic fluid circulating in a closed circuit, said other cryogenic fluid being compressed continuously by a second compressor unit (14-15-16), expa entering through a cryogenic turbine (17) to reach a cooling temperature below the liquefaction temperature of the cryogenic fluid, and then feeding said heat exchanger (19), and because the first cryogenic fluid is also used as a fluid refrigerant in said second compressor unit (14, 15, 16), both for the second intermediate refrigerators (12, 13) and for the second final supply refrigerator (11) of said second compressor unit.