GB638769A - Improvements in or relating to the process for production of carbon monoxide - Google Patents

Abstract

Carbon monoxide is made by reducing a metal oxide, e.g. iron oxide, by a gas-containing carbon monoxide and/or hydrogen to a lower stage of oxidation or to the metal, re-oxidising the thus reduced metal oxide with carbon dioxide to yield a mixture of carbon monoxide and carbon dioxide, and removing the latter therefrom. In a preferred embodiment, a reducing gas, which may be preheated at 21, <PICT:0638769/III/1> is passed through pipe 8, and a heated oxide bed 6 and burned in air and/or oxygen admitted through pipe 10, the resulting gases heat up a superheater 7 and exit through pipe 12, a waste heat boiler 20, which may be byepassed, and the preheater 21 to the atmosphere with or without prior removal of carbon dioxide. The apparatus is then purged by passing carbon dioxide from pipe 18 downwardly through 7 and 6 and out through pipe 14, after which valve 15 is closed and the gases, viz. a mixture of carbon monoxide and carbon dioxide, leave through pipe 16 for subsequent cooling and removal of carbon dioxide. In modifications, the carbon dioxide may be dried before use, preheated or passed in the same direction as the reducing gas, which may be water gas, producer gas, blast furnace gas, distillation gas (coke-oven gas &c.) or industrial hydrogen. The steam from the waste heat boilers may be used for purging the apparatus or for the carbon dioxide recovery process. The carbon dioxide recovered from the spent gases and the carbon monoxide-dioxide mixture may be reused in the process, and the gas, mainly nitrogen, remaining after carbon-dioxide removal from the spent gases may be used as an inert gas or as raw nitrogen. The superheater 7 may be separated from the vessel containing the oxide bed 6 or it may be integral with it, e.g. as an annular space around the bed or the bed may be in an annular space round the superheater.