Abstract: A riser cracking-catalyst regeneration operation is described wherein a suspension discharged from a riser operation is separated by catalyst particle concentrating means which discharge a concentrated stream of catalyst separated from gasiform material into a downcomer zone and out of further contact with discharged gasiform material in the suspension. A stripping gas is used to particularly aid the separation of catalyst and hydrocarbon vapors.

Abstract: In a reactant-fluid catalyst suspension system, an arrangement of apparatus is provided contiguous with a riser discharge which centrifugally initially separates the suspension into a solids phase and a gasiform material phase prior to discharge from the riser. The catalyst may be further stripped if desired in equipment above and about the riser discharge. The arrangement contributes substantially to the efficiency and economics of the separation of catalyst from gasiform products including products of hydrocarbon conversion and combustion products of catalyst regeneration.

Abstract: In a reactant-fluid catalyst suspension system, an arrangement of apparatus is provided contiguous with a riser discharge which centrifugally initially separates the suspension into a solids phase and a gasiform material phase prior to discharge from the riser. The catalyst may be further stripped if desired in equipment above and about the riser discharge. The arrangement contributes substantially to the efficiency and economics of the separation of catalyst from gasiform products including products of hydrocarbon conversion and combustion products of catalyst regeneration.