Abstract In apparatus for retorting oil shale, oil sands and similar materials wherein finely divided solids residue is used as a heat carrier and is heated in a vertical pneumatic conveyor-burner, mixed with fresh finely divided solid feed, product distillation vapors are removed from the mixture, and the solid distillation residue is returned to the conveyor-burner, the improvement whereby the propellant gas is introduced axially to the bottom of the conveyor-burner and the cool heat carrier is introduced thereinto from a concentric annular chamber thereabout through slits or openings in the propellant gas conduit by means of a flow of a control gas. Other specific improvements of portions of the retorting apparatus and solids circulating system are examplified and claimed, especially a screw conveyor-mixer retorting chamber.
The apparatus of claim 1 wherein said first separator has a cross-sectional area in the range of 5 to 20 times the average cross-section of said vertical pneumatic conveyor and the distance from the discharge end of said conveyor to the top of said first separator in the range of 3 to 10 m.
Claim 2
Dependent Claim
22 words
The apparatus of claim 1 wherein at least two of said conveyors operate in parallel and commonly discharge into said first separator.
Claim 3
Dependent Claim
44 words
The apparatus of claim 1 including valve means in said solids discharge conduit from said first separator and in said conduit between said intermediate hopper and said annular chamber, said valve means permitting the build-up of solids in the conduits and said intermediate hopper.
Claim 4
Dependent Claim
30 words
The apparatus of claim 1 wherein said product recovery and cooling system comprises three scrubbers adapted to progressively cool said distillation vapors by contact in each with cooled liquid condensate.
Claim 5
Dependent Claim
31 words
The apparatus of claim 1, wherein said mixing device for water quenching the discharged solids is connected to said product recovery and cooling system so as to receive condensed water therefrom.
Claim 6
Dependent Claim
40 words
The apparatus of claim 1, including a dust gas separator connected to said distillation chamber and to the intermediate hopper so as to receive distillation vapors from said distillation chamber and to discharge dust recovered therefrom to the intermediate hopper.