Improvements in or relating to methods of treating gases

摘要

In a process for converting methane by reaction with steam over a nickel catalyst into CO and H2, the temperature of the catalyst is maintained by means of one or more tubular heating elements contained in the same vessel as the catalyst (said tubular heating elements each comprising an outer, substantially cylindrical casing closed at the forward end and having a flue outlet at the rear end, a tubular portion coaxial with the casing and a burner having a combustion chamber which converges towards an exit coaxial with the cylindrical casing for the discharge of hot products into the outer end of the partition tube which extends nearly from the exit to the closed forward end of the casing but leaves a space beyond its end for the re-circulation of hot products, as claimed in claim 1 of Specification 876,161) and also by means of mixing oxygen with the reactant gases so that combustion takes place with liberation of heat in the catalyst bed. The methane may be in the form of a methane-containing gas produced according to the process of Specification 820,257. Oxygen may be supplied as air. The catalyst temperature may be maintained at 550-800 DEG C. In Fig. 1 pressure vessel 1 encloses bed 3 of reforming catalyst surrounding radiant tube 4; inner tube 6 co-axial with 4 is such as to allow passage of flue gases in annulus 7 while burner tube 8 promotes recirculation of flue gases into 6; flue gases are withdrawn at 9. Steam and methane-containing gas are introduced at 10, and preheated air at 12, the mixture passing through the catalyst and being withdrawn at 11, tube 4 being heated by the passage of combustion products of burner 8 in annulus 7.