PROCESSO PARA A OBTENCAO DE GASES RICOS EM NITROGENIO A PARTIR DE GASES CONTENDO-ALEM DE N2-PELO MENOS O2,COMO POR EXEMPLO,AR

1480866 Nitrogen rich gas BERGWERKSVERBAND GmbH 29 Aug 1975 [29 Aug 1974] 35833/75 Heading B1L A process for obtaining nitrogen-rich product gas from a feed gas containing O 2 and N 2 , comprises rejected cycles in each of which carbon-containing molecular sieve coke is desorbed by evacuation and then charged with feed gas which is caused to flow through the coke until the O 2 content of the emergent gas reaches a preselected limiting value, the gas which has passed through up to this point being collected as product gas. The desorption is preferably carried out below 100 mm Hg, and the feed gas is charged at 2-5 bars at 0.01-0.04 N m3/m3 of molecular sieve coke per second for approximately 40-80 seconds and may be air or gas already passed through the coke. The direction of gas flow during desorption may be opposite to that during charging. The sieve coke may be prepared as described in Specifications 1424501 and 1364674.