Conversion of Coal-Mine Drainage to Potable Water by Ion Exchange

processes is still unresolved problem of economical sludge disposal. Pennsylvania, in one of its steps in seeking to find solutions to the minedrainage problem, has tackled the combined problem of mine-drainage abatement and water supply. Several projects supported by the state have been aimed at the regeneration of mine drainage for reuse. The various techniques that may be applied to mine-drainage demineralization include: evaporative processes, distillation processes, and membrane and ion-exchange processes. Flash distillation. On Feb. 1, 1965, the Coal Research Board, using coal-industry funds exclusively, issued a grant to the Westinghouse Electric Corp. to perform a feasibility study on the use of flash distillation for the processing of mine drainage. The results of this study indicate that there is every reason to believe that mine drainage can successfully be processed in a flash distillation unit. A second project was undertaken by the same corporation for the Coal Research Board. Under the terms of this grant, a pilot plant was constructed at Lester, Pa. At first, synthetic mine drainage was run through this plant; later, natural drainage was run. The plant processed up to 10,000 gal with a high degree of success. Concurrently with the study by Westinghouse of the engineering principles in designing a mobile stage flash-distillation unit, corrosion studies were conducted* These material studies indicated that titanium would hold up satisfactorily in the tube walls. The pilot-plant tubes therefore were constructed of this ma