MAIN FACTORS INFLUENCING EFFICIENCY OF PROCESSING LARGE PARTICLE OIL-SHALE IN VERTICAL RETORTS

World-wide experience of retorting large particle oil shale demonstrat es that known types of retorts are characterized by differing degrees of process efficiency. The latter depends on several factors influenci ng the process. In this paper an attempt in made to systematize the in fluence of these factors affecting, above all, the oil yield in vertic al retorts. The present review, of course, does not pretend to be comp lete and does not consider all possible features playing a role in the process of retorting large particle shale under industrial and pilot- scale conditions. However, estimating the effect of those factors may be useful for further improvement of oil shale processing units. The c omparison of data characterizing the efficiency of thermal processing of large particle oil shale in different types of retorts usually lead s to the conclusion that the design features play a decisive role in e fficient operation of the retorts. It is not sufficient, however, to c onsider the design features only. A great deal also depends on the pro perties of feed shale and the operating conditions in the process.