| 摘要 |
<p>A raw material for use in the production of cement is produced by treating oil shale in grannular or size reduced form in a fluidised bed, at e.g. 400-650 DEG C., operated with a deficiency of O2 relative to the total combustible organic matter to effect combustion of only the more volatile constituents of the oil shale and the liberated heat is used to raise steam. The oil shale may be milled up to 5 mm. grain size. The residence time of the shale in the fluidised bed may be from a few seconds to a few minutes using a gas containing less O2 than air or a deficiency of air whereby 2/3 rds of the organic matter is burnt yielding a combustion gas containing not more than 0- 1/2 %O2. Steam may be raised by cooling tubes in the bed and radiation chamber above the fluidised bed. The solid C left on the shale may be used to provide at least part of the heat required for sintering, e.g. on a sinter board.</p> |
