METHOD AND DEVICE FOR LOW-TEMPERATURE COOLING/LIQUEFACTION

摘要

The invention relates to a method for low-temperature cooling/liquefaction of a working fluid, in particular a working fluid including helium or consisting of pure helium by means of a refrigerator/liquefier that includes a working circuit provided with a compressor station (2) and a cold box (3). The refrigerator/liquefier subjects the working gas within the working circuit to a cycle that includes, in series: compressing the working fluid within the compressor station (2), cooling and decompressing the working fluid in the cold box (3), and heating the working fluid with a view to the return thereof to the compressor station (2). The compressor station (2) includes one or more compression levels, each one using one or more compressors (12) mounted on landings (5). The method is characterized in that the refrigerator includes a device (4) for injecting a seal gas that is separate from the working fluid on at least one landing (5) of the compressor(s) so as to form a gas seal that guides the working fluid leaks, coming from the working circuit, to an area (13) for recirculating and returning (13, 21) the fluid into the working circuit.