PATENT

3539. ----- [STANDARD OIL CO.]  Production of Water Gas From Solid Carbonaceous Materials.  British Patent 626,743, July 20, 1949; appl. filed Feb. 14, 1947.  fuel Abs. 1949, abs. 4812.  British Abs., I, B, 1950, p. 260; chem.. Abs., vol. 44, 1950, p. 8093.

Gas mixtures containing CO and H₂ are produced from solid carbonaceous materials and steam by passing the latter into a gasification zone containing a mass of finely divided solid carbonaceous material having an oxidation reactivity of T₁₃=200°-250° and T₇₅=250°-300° under such conditions as to form a dense fluidized mass of finely divided solid.  The residual solid is removed from the gasification zone, subjected to treatment in the form of a fluidized ebullient mass with an oxidizing gas mixture to burn off the residual carbonaceous material and thereby heat the residual solid to a high temperature and the heated solid recycled to the gasification zone to use the sensible heat of the heated solid to supply at least part of the heat required in the gasification zone.  T₁₅ and T₇₅ are the temperatures at which the rate of heat release by oxidation of a sized sample becomes great enough to raise its temperature at rates of 15° per min. and 75° per min., respectively.  The preferred high reactive carbonaceous starting material is low-temperatures, preferably 316°-510°, to an oxidation reactivity of T₁₅=200-10°, and T₇₅=250-60°.  When low-temperature may be lowered as much as 90°-180° beneath the level required for conventional charging materials, such as coal or high-temperature coke, with out affecting steam conversion under other wise equal conditions.  Steam conversions of 98-99% may be achieved at temperatures of about 1,038, whereas at 927° the steam conversion still amounts to about 80%.  Oother suitable carbonaceous materials include certain bituminous or subbituminous coal, lignites, and brown coals uncoked, or coked at temperatures preferably 316°-538°.