VORRICHTUNG UND VERFAHREN ZUM VERFLÜSSIGEN VON ERDGAS ODER BIOGAS

摘要

The invention relates to a method (300) for liquefying a natural gas or a biogas, said method comprising: a first step (305) of compressing a vaporised refrigerant mixture; a first heat exchange step (310) for cooling the compressed refrigerant mixture; a step (315) of expanding the cooled refrigerant mixture; a second step (320) of compressing vaporised carbon dioxide; a second heat exchange step (325) for cooling the compressed carbon dioxide; a first step (330) of heat exchange between: the gas and the expanded refrigerant mixture (330a) in order to cool the gas, the vaporised refrigerant mixture being supplied in the first compression step, the expanded refrigerant mixture and the cooled carbon dioxide (330b) in order to cool the carbon dioxide, the cooled carbon dioxide being supplied in a step of expansion of the carbon dioxide, and the gas and the expanded carbon dioxide (330c) in order to cool the gas, the vaporised carbon dioxide being supplied in the second compression step; and the step (335) of expansion of the carbon dioxide cooled in the first heat exchange step, the expanded carbon dioxide being supplied in the first heat exchange step.