| 摘要 |
A method and device is disclosed for removing residual oil and other contaminants from the refrigerant stream flowing to low-temperature stages of a cryogenic refrigerator. A stream of vapor and liquid refrigerant coming from an air-cooled condenser is injected into a cyclone chamber [32] through the inlet tube [34]. While the liquid drains down a conical section [36] and out through a liquid line [38], the vapor phase moves up into a packing of metal platelets [42] which is cooled by a returning stream of cold vapor passing through a tube [48] wrapped around the column. A portion of the vapor condenses on the platelets and is maintained in equilibrium with the vapor. Since high-molecular-weight contaminants are more soluble in the liquid phase, they are carried down the column with the drops of condensate and are swept out with the liquid fraction through the liquid line [38]. Consequently, the vapor sent out vapor line [46] and into the low-temperature stages of the refrigeration system is cleansed of all oil residues and contaminants. A low-temperature refrigeration system with such a device can be operated continuously for many weeks with no signs of clogging. Moreover, the fractionating column is inexpensive, contains no moving parts, and does not add significant volume to the system. |
