810a. ELLIOTT, M. A., PERRY, H., JOHAKIN, J., COREY, R. C., AND KHULLAR, M. L. Gasification of Pulverized Coal With Oxygen and Steam in a Vortex Reactor. Ind. Eng. Chem., vol. 44, 1952, pp. 1,074-1,082. An experimental study has been made of the gasification of pulverized bituminous C coal with O2 and steam in a vortex-type reactor at atmospheric pressure. The potentialities of this type of reactor for producing synthesis gas were investigated. The unit was operated downflow with continuous removal of slag. Most of the data was obtained in coal throughputs of 100 lb. per hr., steam : coal ratio of about 0.5 lb. per lb. of coal. The O2 and steam feed streams could be preheated to 1,300° F. All tests were made at a constant reactor diameter of 2 ft. with a 4-in. diameter outlet, but with reactor depths of 8, 24 and 36 in. In most of the tests, all of the O2 entered the reactor through tangential slots at the periphery. In some tests, part of the O2 entered the vortex just beneath the coal stream. The coal was always fed to the reactor from a rotating, H2O-cooled plate at the top. The effect of ratio of O2 : coal and depth of reactor on C conversion, production of CO+H2 per lb. of coal and per ft.3 of O2, are shown and discussed in detail. The best gasification results were obtained when part of the O2 was admitted with the coal. For example, in the 36-in. vortex the C conversion ranged 78-94% for the range of O2 : coal ratio of 8-11 ft.3 O2 per lb of coal. At 8 ft.3 of O2 per lb. of coal, approximately 41 lb. of coal and 329 ft.3 of O2 were required for the production of 1,000 ft.3 of CO+H2, even with the heat losses from the shell of about 1,000 B.t.u. per lb. of coal. This heat loss is thermodynamically equivalent to an O2 consumption of about 80 ft.3 per 1,000 ft.3 of CO+H2. The critical factors to be considered in interpreting experimental results on the suspension gasification of coal with O2 and steam are discussed. |