| 摘要 |
1,120,834. Cold separation of gas mixtures. AIR PRODUCTS Ltd. 27 July, 1965 [29 July, 1964], No. 30127/64. Heading F4P. A reflux condenser 29 at the head of a gas mixture separating column 12 and a reboiler 26 at the base thereof are cooled and warmed respectively by a refrigerant, e.g., nitrogen, in a closed cycle, wherein the nitrogen having been compressed to about 3000 p.s.i. at 19 is expanded to an intermediate pressure of 140 p.s.i. at a valve 22 into a first separator 23 from which vapour is withdrawn, condensed in the reboiler 26 and expanded to a low pressure of 60 p.s.i. at a valve 30 into a second separator 16 into which is also expanded at a valve 28 liquid withdrawn from the first separator 23, and liquid withdrawn from the second separator 16 is passed through the condenser 29. Low pressure nitrogen gas from separator 16 is returned to the compressor inlet through a heat exchanger 27 traversed by liquid nitrogen withdrawn from separator 23, and heat exchangers 11, 15 in parallel traversed by feed gas mixture and high pressure nitrogen respectively. Intermediate pressure nitrogen gas withdrawn from separator 23 together with part of the high pressure nitrogen after cooling at 24 and expansion at a turbine 25 is returned to an intermediate stage of the compressor 19 through heat exchanger 15. Feed gas may be oxygen-containing nitrogen and liquid nitrogen product is withdrawn through a line 13 whilst oxygen-enriched liquid nitrogen is withdrawn through a line 14 and is passed through heat exchanger 15. |
