3523.     UNITED STATES BUREAU OF MINES.  Production of Synthesis Gas From Wyoming Subbituminous Coal.  General Investigation of Methods and Flowsheet for Plant to Process 8,000,000 Cubic Feet per Day.  Special Report, November 1946, 23 pp.

        To obtain general information on the advantages and disadvantages of various methods of producing synthesis gas from a coal like the Wyoming coal, 4 methods are considered suitable for treating this coal, and calculations are made of the investment and production costs for a plant with a capacity of 100,000 N m.³ per hr. of synthesis gas.  the high content of H₂ of Wyoming coal promises very high tar content and consequently, very favorable conditions for utilizing it for the production of motor fuels by combining carbonization and byproduct gasification with the synthesis of hydrocarbons and hydrogenation of tar.  The 4 methods investigated are:  Lurgi pressure gasification; combined carbonization-gasification with O₂ and with burning of coke and cracking of carbonization gas; the same with use of air in the 1^st step and O₂ in the 2d with burning of the carbonization gas and gasification of the coke; and the Koppers complete gasification of powdered coal.  Cost of equipment is taken from figures available from German sources.  Corresponding figures for the United States are calculated with the ratio of 1 RM:$0.50 for the investment cost and 1 RM:$1.00 for the cost of labor, with a rough adjustment for special work.

        Further calculations on 3 so-called pioneer plants A, B, and C:  Carbonization-gas producer plant; Koppers pulverized-coal gasification; and Lurgi pressure gasification give production costs per 1,000 N m.³ on the basis of capacities of 8,000,000 cu. ft. of ideal gas per day and 320 operating days, respectively, of $9.30, $11.80, and $11.50.  Here again the combined carbonization-gasification method is found to be the most favorable one.  It is proposed to erect 2 units of the carbonization-gasification type with the necessary equipment for operating each of the units for the production of gas as well as for the carbonization of coal and the production of coke, as this seems the safest, cheapest, and most-flexible method with respect to the requirements of a pilot-experimental plant, which should be able to handle various types of coal from such standpoints as tar recovery and alteration of the CO:H₂ ratio.  It might also prove an economical method for the treatment of oil shales with more than 10% of oil.

Investment costs and production figures for 100,000 N m.³ per hour of synthesis gas