Effects of low temperature preheating on the pyrolysis products from blocks of oil shale

Oil shale is a sedimentary rock composed of inorganic and organic fractions. The inorganic minerals contained in oil shale include: dolomite, calcite, quartz, i1 lite, albite, microline, pyrite and anal-cite (Smith, 1969). The organic material, first labeled kerogen by the Scotsman Oum Brown (McKee et at., 1925), yields liquid and gaseous hydrocarbon products when heated. A carbonaceous residue remains on the retorted shale. The Green River Formation of Colorado, Utah and Wyoming contains a vast resource of oil shale estimated to embody over two trillion barrels of oil (Dinneen and Cook, 1974). The estimated yield drops to about six hundred billion barrels if only the deposits at least ten feet thick that average a minimum of twenty-five gallons Per ton are considered. Recovery of the petroleum-like products from oil shale has proceeded by above ground retorting (Schora et al.t 1977a), and underground mi situ methods (Schora et at. 9 1977b). A recent economic study by Dickenson (1977)