Superatmospheric pressure shale retorting process

Claim 1

In a shale retorting process wherein crushed oil shale is gravitated downwardly through a feed conduit into a feeder cylinder which alternately receives a charge of shale and then discharges the same upwardly by means of a reciprocating piston into the bottom of a communicating retort, and wherein the upflowing shale in said retort contacts hot, non-oxidative, downflowing education gases to educe product oil and gas from said upflowing oil shale, said oil and gas being discharged from the bottom portion of said retort into an isobaric product collection vessel in which a first liquid level of oil is maintained, and wherein hot, retorted shale overflowing the top of said retort is transferred through a gas-tight transfer conduit to a water quenching zone, the improvements which comprise: 1. maintaining substantially continuous hydraulic communication between the product oil in said collection vessel and the bottom of said feed conduit, whereby a second liquid oil level is maintained in said feed conduit; 2. maintaining a first liquid water level in said quenching zone, substantially below the top of the retorted shale bed maintained therein, whereby a quench gas mixture comprising superheated steam and combustable water gas is generated in said quenching zone; 3. removing shale from the bottom of said quenching zone through an upwardly extending outlet conduit communicating therewith below said first liquid water level, whereby a second liquid water level is maintained in said outlet conduit, the rate of removal of said retorted shale being controlled so as to maintain the top of said retorted shale bed substantially above said first liquid water level; and 4. maintaining superatmospheric pressures throughout said retort while preventing the discharge of retort gases through said feed conduit and said outlet conduit solely by means of the hydrostatic seals established by the oil in said feed conduit and by the water in said outlet conduit.