| 摘要 |
<p>1436542 Separating gases AIR PRODUCTS & CHEMICALS Inc 10 May 1973 [10 May 1972] 21984/72 Heading F4P A method of obtaining carbon monoxide (CO) from a pressurized feed stream containing hydrogen, CO, not more than 1 mole per cent of CO 2 and not more than 1 mole per cent of water vapour and possibly some nitrogen and methane comprises freezing out the CO 2 and water vapour in a heat exchanger E101 having two sets of passages 60, 61, the feed stream in one passage being cooled by a hydrogen rich stream at a lower pressure than the feed stream, in the other passage, the exchanger being derimed by reversing the connections to the exchanger periodically. The cold feed stream is led via line 16 to a methane wash column 17, from the top of which issues the hydrogen-rich stream which is work-expanded at 58 before effecting the cooling in exchanger E101. The liquid bottoms from column 17 are reduced in pressure in two stages into separators 20, 21, from which gaseous hydrogen is removed and fed through line 36 to exchanger E101. The liquid from separator 21 is partially vaporized in exchanger E104 and fed to a distillation column 26 to separate CO from methane. The CO which forms a heat-pump circuit is fed via line 37 to exchanger 102, some being branched through exchanger E101, the recombined streams at ambient temperature being compressed and removed as product, or further compressed, cooled in exchanger E102 and liquefied in reboiler E103, some of this liquid being refluxed to column 26, the remainder being expanded at valve 52, warmed in exchanger E104 and, partially vaporized, enters separator 54, the liquid from these cooling the column 17, the gas being recycled to the heat-pump circuit. The liquid methane from column 26 is compressed at 29 cooled in separators 21, 20 and exchanger E104 and fed to the wash column 17.</p> |
