| 摘要 |
<p>781,370. Gas manufacture. COMPAGNIE GENERALE DE CONSTRUCTION DE FOURS. Feb. 7, 1956 [Feb. 7, 1955; May 3, 1955], No. 3807/56. Class 55 (2). Gaseous hydrocarbon is converted into a combustible gas of lower calorific value by controlled oxidation of the hydrocarbon over a catalyst in the presence of water vapour, a mixture of oxygen-containing gas and water vapour being supplied to a reaction chamber through a duct having a constriction adjacent to the reaction chamber, the gaseous hydrocarbon being admitted into said duct at or upstream of said constriction. As shown, air and water vapour are passed downwardly through a duct 4 into a catalyst bed 3, the duct having a venturi constriction 5 into which projects the hydrocarbon gas feed-pipe 8. This pipe is closed at the top, the gas issuing through holes 9 into the air-water vapour stream and being dispersed by elements 6 into the catalyst bed. The duct 4 is protected in the bed by a refractory sleeve 7. The catalyst is preliminarily heated by a burner in the passage 12, the fumes from which escape at 15. The passages 12, 15 are then closed and the air, water-vapour, and gas are admitted. The hot product gas passes up the tube 10 and heats the air and water vapour, the heat-exchange being enhanced by radial vanes on the duct 4 projecting into the tube 10, and by a spiral baffle in the duct 4 which increases the turbulence therein. In a modification, the preheating of the air-water vapour mixture is dispensed with, the duct 4 passing upwardly into the bottom of the catalyst bed and the fuel feed tube delivering into the venturi at the top of the duct 4.</p> |
