| 摘要 |
Purification is carried out in scrubber under pressure (pref. above critical pressure of N2), using N2 which is precooled, passed to scrubber under pressure of scrubber and removed as impure liquid at foot of scrubber and expanded. Precooling is carried out in liquid bath (pref. of N2, esp. sump liquid from scrubber) or normal or sub-atm. pressure, having vapour space connected to suction side of ejector by which scrubbing liquid under pressure is expanded through valve and discharged. Low precooling temp. is reached without additional use of vacuum pump. |
