| 摘要 |
PCT No. PCT/FR84/00303 Sec. 371 Date Aug. 14, 1985 Sec. 102(e) Date Aug. 14, 1985 PCT Filed Dec. 26, 1984 PCT Pub. No. WO85/03072 PCT Pub. Date Jul. 18, 1985.The gas to be treated is cooled and partly condensed in two steps (3-4, 5-6), and the condensed fractions are distilled in a column (9). A part of the condensed liquid at the top of the column is subcooled in the second exchanger 5, expanded, and vaporized in counter-current to the gas to be treated. This permits the obtainment of cooling temperatures on the order of -80 DEG C. by means of a refrigerating unit (13, 20) operating at a temperature on the order of -30 DEG to -40 DEG C. Application to the recovery of a mixture of propane, butane and pentane from a petroleum refinery residual gas. |
