Process of cooling hot granular solids

Claim 1

A process of cooling hot granular solids which have been made available by the dry distillation of oil sand, oil shale, oil chalk, diatomaceous earth or native asphalt as fresh material, said distillation comprising mixing said fresh material with devolatilized reheated residual solids of a temperature in the range of 500° to 900° C. from a collecting zone, devolatilizing said fresh material and creating a mixture of residual solids, a first partial stream of said mixture of residual solids being fed to the lower end of a vertical pneumatic conveyor line together with preheated combustion air, by combustion gases reheating said residual solids in the conveyor line and conveying them upwardly into said collecting zone, granular solids selected from the group composed of a second partial stream of said mixture of granular solids or a partial steam or reheated solids from the collecting zone or a mixture of both streams, these granular solids having a carbon content of 1 to 15 percent by weight, being fed into a combustion zone, said carbon content being at least partly burned therein by a supply of combustion air and said granular solids in said combustion zone are heated to a temperature in the range of about 600° to 1300° C., feeding said granular solids heated in said combustion zone to a cooling zone, in said cooling zone, maintaining said granular solids in an agitated or trickling state and causing air to rise through said cooling zone in direct contact with the granular solids, utilizing at least part of the sensible heat of the granular solids dissipated in the combustion zone or cooling zone for preheating the combustion air fed into the pneumatic conveyor line, the cooling zone being constituted by a multi-chambered fluidized bed zone or a trickling zone.