Abstract: An apparatus for a process for solar retorting of oil shale which comprises pyrolyzing fluidized ground oil shale particles by solar radiation in a retort, wherein said ground oil shale particles are provided in a state of continuous fluidization entrained in a gas and exposed to solar radiation focused through a transparent window, and retorted shale oil fines, gases, and shale oil are removed from the retort to separation and recovery.

Abstract: A process for replacing a solution obtained for instance by exposing oil shale particles to the action of a solvent under supercritical conditions, by a solvent is provided for. The solid/solution mixture is extracted in a multitude of cross flow extractions such as to gradually replace the solution e.g. a bitumen solution, by the solvent, e.g. toluene. An apparatus for carrying out this process is also disclosed.

Abstract: In accordance with the present invention, mineral values are recovered from subsurface earth formations containing the same as well as calcium-containing materials by injecting into at least one injection well an aqueous sulfuric acid leach solution adapted to extract such mineral values from the subsurface formation and containing a solubility increasing agent, such as sodium chloride, adapted to significantly increase the solubility of calcium sulfates in water, in an amount sufficient to thus increase the solubility of calcium sulfates in water, contacting the subsurface earth formation with the leach solution for a time sufficient to extract significant amounts of mineral values from the formation and produce a pregnant leach solution containing the thus extracted mineral values and to thus solubilized significant amounts of calcium sulfates and withdrawing the pregnant leach solution from at least one producing well.

Abstract: Finely divided particulate solids are discharged from a high pressure zone to a low pressure zone, e.g. to atmospheric pressure, by passing a dense bed of this particulate material through a long discharge channel and past a throttle element. The pressure drop across the throttle element is significantly reduced due to the fact that the moving dense bed in the discharge channel dissipates the pressure drop along this channel leaving only a small pressure drop to be achieved across the throttle element.

Abstract: A process for replacing a solution obtained for instance by exposing oil shale particles to the action of a solvent under supercritical conditions, by a solvent is provided for. The solid/solution mixture is extracted in a multitude of cross flow extractions such as to gradually replace the solution e.g. a bitumen solution, by the solvent, e.g. toluene. An apparatus for carrying out this process is also disclosed.