GB947164A - Improvements in or relating to the production of combustible gas - Google Patents

Abstract

<PICT:0947164/C3/1> A cyclic process for producing combustible gas from fluid hydrocarbons by a catalytic process includes in each cycle a plant-heating period which comprises passing through the plant and catalyst bed 41 a hot mixture of inert gases, e.g. nitrogen or carbon dioxide or products of combustion, with or without air, see Fig. 1 (not shown), the mixture having a temperature in the range 900 DEG to 1200 DEG C. and a free oxygen content of between 3% and 8% of the total gases, including water vapour. The plant may be of the uniflow, non-regenerative type, Fig. 1, or of the regenerative type shown in Fig. 2. During a gas-making period, steam is introduced at 55 and, after passing over pre-heated chequer bricks 43, is mixed with oil to be reformed which is sprayed at 56 into a chamber 42. The mixture passes over the catalyst 41 and chequer bricks 47 in an air pre-heater 46 to an outlet 49. During a plant-heating period, air is delivered by conduits 58 . . . 60 to the pre-heater 46 and fuel (oil) and air entering respectively at 61, 62 are burnt in a chamber 45, the products of combustion passing over catalyst 41 and bricks 43 to an outlet 54. Some of these products are recycled via conduits 63, 65, 60 and additional air and fuel may be burnt at 68 in the chamber 42. Control of the various proportions of fuel, air and products of combustion employed during the plant-heating period enable the temperature and oxygen content of the gas mixture passing over the catalyst 41 to be controlled.