| 摘要 |
1380276 Gas manufacture TEXACO DEVELOPMENT CORP 7 Dec 1971 [28 Dec 1970 (2)] 56673/71 Heading C5E A mixture of gases comprises hydrogen, carbon monoxide and methane is produced by (1) introducing into the reaction zone of a non- catalytic, free-flow synthesis-gas generator and mixing together therein a hydrocarbonaceous fuel, an oxygen-rich gas, and H 2 O; (2) reacting the materials together in the reaction zone at an autogenous temperature of 1200‹ to 3000‹ F. and at a pressure of 1 to 250 atmospheres and, discharging an effluent gas mixture from the reaction zone comprising methane, hydrogen, carbon monoxide, carbon dioxide and water vapour; (3) mixing supplemental steam with the effluent gas mixture and reacting together H 2 O and CO in the mixture in a separate freeflow, non-catalytic water-gas shift conversion zone at a temperature of 2800‹ to 1500‹ F. thereby increasing the mole ratio H 2 /CO in the process gas stream; (4) cooling the process gas stream from (3) and separating therefrom any gaseous or other impurities thereby producing a process gas stream comprising methane, H 2 and CO; (5) reacting together the H 2 and CO in the process gas stream from (4) while in contact with a methanation catalyst to produce a methane-rich gas stream. Gaseous impurities may be removed from the methane-rich gas stream of step (5) to produce substantially pure methane. In step (5), the temperature may be 390‹ to 1000‹F. and the pressure 1 to 250 atmospheres; the process gas stream is free from H 2 O and CO 2 and has a H 2 /CO ratio of 2À5 to 3À5 : 1; and may be effected by passing the process gas through tubing coated with methanation catalyst, e.g. NiO-Al 2 O 3 or NiO-MgO precipitated on kaolin and reduced with hydrogen, 33 to 78% by wt. nickel oxide and 12 to 25% by wt. aluminium oxide, or 100 parts by wt. nickel, 6 parts ThO 2 , 12 parts MgO and 400 parts kieselguhr. In step (1), the ratio of H 2 O to fuel in parts by weight may be 0À1 to 6 : 1; and the atomic ratio of free oxygen to carbon (O/C ratio) from 0À60 to 1À2 : 1. In step (2) the autogenous temperature may be 1200‹ to 2200‹ F. and the pressure from 15 to 250 atmospheres. The pressure throughout the system may be substantially the same as the pressure in the reaction zone of the free-flow synthesis-gas generator, less ordinary line drop. The hydrocarbonaceous fuel is a liquid hydrocarbon fuel or a pumpable slurry of a solid hydrocarbonaceous fuel in water or in a liquid hydrocarbon fuel. Specification 1,380,277 is referred to. |
