P ment in oxygen and superheated steam are being developed in small and large pilot plants a t the Morgantown, W. Va., Station of the Bureau of Mines, U. S. Department of the Interior, under a cooperative agreement with West Virginia University.The initial work of development and operating results obtained as progressive improvements advanced the project toward the solution of many hitherto unknown problems have been d e scribed from time to time in the literature (1,3,(8)(9)(10)(11).From the start it was realized that, since there are enormous differences in chemical and petrographic composition as well as chemical and physical properties of the many varieties, ranks, and grades of coals in the United States, there would be strong necessity for a practical laboratory scale method to test various fuels for their utility in synthesis-gas production. Accordingly, a laboratory scale method was developed for the continuous production of synthesis-gas (essentially CO + Hz) by entrainment of powdered coals in oxygen and superheated steam. The laboratory scale pilot plant, which gasifies various types of fuels a t rates up to 55 pounds per hour, has been in operation for about 4 years (IO) and has furnished design data for building considerably larger pilot plants. Principally, however, the information obtained in testing various types and grades of coals served as a guide to operating conditions for other, larger scale gasifiers at the Morgantown Station. The suitability of the coal for synthesisgas production on commercial basis was thus determined.It soon became evident that all coals do not gasify alike in a generator of given design but differ vastly in their behavior, and coals that appear to give the worst results are frequently available in given localities at the lowest price. It was desirable, therefore, that an investigation of the effects of process variables should determine under what conditions a given coal can be gasified with maximum efficiency, lowest oxygen and steam requirement, and, hence, lowest cost. In the work described, an attempt was made to approach this objective by analyzing the independent and dependent process variables and to determine the effects of the former on the latter. The respective significance of each is discussed.EQUIPMENT AND PROCEDURE Figure 1 shows that the apparatus consists of ( a ) pneumatic feeding system, ( b ) gasifier, ( c ) residual dust-removal system, and ( d ) auxiliaries (condensers, exhauster meter, storage tank, vent pipe, and instrument-control system). Pictures of the labore tory scale pilot plant are shown in Figures 2 and 3, representing the upper and lower floors, with the gasifier, next to the control board on the upper floor, extending to the floor below. Details ~ of construction of various parts of the unit, including the gasifier, have been given in two Bureau of Mines' reports, one of which has already been ublished (IO).Pulverized coa]Pis fed continuously, at rates up to 55 pounds per hour, int.0 the top of the gasifier from the continuous feeder c...
