A method for the improvement of the temperature in a warmth by means of support between the high-pressure nitrogen and hydrogen - nitrogen - mixture in the production of ammonia synthesis gas

摘要

1294928 Hydrogen purification process MESSER GRIESHEIM GmbH 22 Dec 1970 [9 Jan 1970] 60847/70 Heading F4P Liquidation of a compressed nitrogen stream 15 to provide wash liquid for a hydrogen purification column 3 is effected by cooling in an indirect heat exchanger 11 traversed by reverse flowing portion of top gas 10 from column 3, withdrawing at 16 a portion of feed nitrogen, work expanding at 17, liquefying in an exchanger 18 in heat exchange with impurity-laden bottom liquid from column 3 and forcing by a pump 20 into the wash line 4, throttle-expanding at 23 a portion 22 of the feed nitrogen leaving the cold end of exchanger 11 and adding it to line 4 and either throttle expanding at 21 a portion 13 of the feed nitrogen leaving the cold end of exchanger 11 and adding it to the top gas in line 10 prior to its entry into exchanger 11 or withdrawing a portion 12 of the liquid nitrogen discharged by pump 20 and adding it to said line 10; the temperature of said nitrogen portions 12, 13 being below the critical temperature of nitrogen. The mixture of top gas portion and nitrogen leaving the warm end of exchanger 11 is added at 14 to the remainder of the top gas after the latter has served to cool the crude feed hydrogen in an exchanger 2. Compressed nitrogen in a line 8 is also added at 14. Exchanger 11 is also cooled by a reverse flow at 24 of part of the work expanded nitrogen.