GB647706A - Improvements in and relating to the manufacture of gas from coal and like carbonaceous material - Google Patents

Abstract

647,706. Gasifying solid carbonaceous materials. BAMAG, Ltd., LAIDLER, K., and WISNIEWSKI, J. June 19, 1946, No. 18419. [Class 55 (i)] ] Gases comprising mainly hydrogen and oxides of carbon are continuously produced by contacting disintegrated carbonaceous material with gases containing oxygen and steam in a reaction zone in which the gases under 5-50 atmospheres pressure move upwardly at a velocity causing the material to "float." The gases may be injected at spaced points and external heating or cooling applied through the producer walls to control localized reaction temperatures. Part of the product gases may be recycled to serve as a carrier for the material or to take the place of nitrogen when oxygen instead of air is employed in generating a nitrogen-free water gas. A mixture with a low methane content for ammonia synthesis is obtained by introducing steam and air enriched with oxygen at a pressure preferably between ten and twenty atmospheres into a chest 15 'and thence through passages 14 into a reaction shaft 1, fines of lignite, brown or bituminous coal, low temperature coke &c. being fed through a screw 4 near the base. Product gases escaping through an outlet 28 are preferably cleaned and treated to convert carbon monoxide to dioxide and remove it before reduction of pressure. Secondary air or oxygen may be introduced through pipes 25, 26. The fuel is introduced at the upper end of the shaft of a producer, Fig. 4, suitable for generating gas of high calorific value, the gas velocity at the level of the feeder screw being slightly above that of the smaller particles of material which are carried into a separating chamber 29. Fly ash descending a pipe 33 may have residual carbonaceous material burnt out by injection of oxygen through pipes 34, the ash being discharged molten and quenched as by water, steam for use in the process thereby being generated. Specification 558,879 is referred to.