| 摘要 |
The air flow passes through the following stages: (a) compression to a pressure greater than 1 bar; (b) cooling the air to a cryogenic temperature less than -120 deg. C; (c) cryogenic distillation of the air. The process includes at least one stage of eliminating at least part of the aerosols in the air flow. Installation for carrying out the process The aerosols are hydrocarbons, oils or oxidizable components and their size is of the order of 0.1 micro m to 0.2 micro m. At least one stage of eliminating the aerosols is carried out before stage (b) and/or at least part of the aerosols are eliminated by filtering the air flow by passing it through a cooling loop and across a granular bed by centrifuging the air or passing it through a cyclone. At least one stage of eliminating the aerosols is carried out after stage (b), inside the distillation column by filtering and/or purging a cryogenic liquid obtained from air. The filtration is carried out on a cryogenic liquid contained in the vaporizer/condenser bath in a medium pressure column. Preferably, the cryogenic liquid is a mixture of nitrogen and oxygen. In stage (a), the compression is to a pressure greater than 2 bar, preferably between 3 and 40 bar. The air is filtered prior to the compression stage. Nitrogen, oxygen or argon are recovered from the process.
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