Other

Stone & Webster Engineering Corp.

Robert W Pfeiffer

Robert R Dean

Jean-Louis Mauleon

Lisbeth T Pfeiffer

Apparatus and processes are disclosed for carrying out chemical reactions of the type in which a fluidized particulate solid is contacted with reactants in a reaction vessel or conduit and then separated from the reactant products and regenerated in a regeneration process, such as combusting the carbonaceous deposit which accretes on fluid catalytic cracking catalyst particles. The regeneration reaction may change the temperature of the regenerated catalyst particles and in such case it is often required to subject the particles to heat exchange to provide them at a temperature suitable for recirculation to the reaction zone. The processes and apparatus of the invention essentially provide for dividing the fluidized solids regeneration bed into an uppermost bed zone and at least one lower bed zone by a horizontal occlusion zone disposed at a vertically intermediate portion of the bed. The regeneration is fully or partially carried out in the uppermost bed zone, and further regeneration of and/or heat exchange with the regenerated particles is carried out in the occlusion zone and/or the lower bed zone. The intermediate occlusion zone inhibits backmixing of the fluidized particles, thereby permitting suitable temperature differences to be maintained between the fluidized beds.

Processes using fluidized solids and apparatus for carrying out such

A control valve well-suited for controlling the flow of particulate solids comprises a valve body having a flow passageway comprising inlet and outlet passages extending transversely to a slide chamber. A plug member having a flow orifice is mounted for movement within the slide chamber to seal the flow passageway when the flow orifice is out of register therewith and to connect the inlet and outlet passages in flow communication when registered therewith. One of the inlet passage and the flow orifice has a cross section including a tapered slot portion which terminates in an apex defining an angle of from about 45 to 90 degrees and an associated polygonal base portion or circular arc base portion subtending from 225 to about 270 degrees of arc. The other has a peripheral shape which includes a leading edge disposed substantially perpendicular to the direction of travel of the plug member. This arrangement provides valves of enhanced rangeability with a unique logarithmic flow characteristic which, for most flow rates, is intermediate to linear and equal percentage flow characteristics.

Valve with truncated aperture providing enhanced rangeability and

A control valve well-suited for controlling the flow of particulate solids comprises a valve body having a flow passageway comprising inlet and outlet passages extending transversely to a slide chamber. A plug member having a flow orifice is mounted for movement, within the slide chamber to seal the flow passageway when the flow orifice is out of registration therewith and to connect the inlet and outlet passages in flow communication when registered therewith. The flow orifice has a cross section including a tapered slot portion which terminates in an apex defining an angle of from about 45 to 90 degrees and a rectangular base portion or a circular arc base portion subtending from 225 to about 270 degrees of arc. This shape provides valves of enhanced rangeability with a unique logarithmic flow characteristic which, for most flow rates, is intermediate to linear and equal percentage flow characteristics.

Valve with enhanced rangeability and logarithmic flow characteristic

A gas-solids separator to remove particulate solids from a mixed phase stream of solids and gas which has a frusto-conical chamber having substantially conical walls tapering downwardly and outwardly and means defining at least one opening in said conical walls for conveying through the conical walls substantially solids free gas separated from the mixed stream of solids and gas.

Rough cut solids separator

An improved valve well-suited for controlling the flow of particulate solids comprises a valve body having a flow passageway comprising inlet and outlet passages extending transversely to a slide chamber. A plug member having a flow orifice, which is preferably of extended length extending transversely through it is mounted for sliding movement within the slide chamber to seal the flow passageway when the flow orifice is out of register therewith and to connect the inlet and outlet passages in flow communication when registered therewith. The flow orifice is preferably of ovoid cross-section and provides, at all operating positions of the valve, a cross-sectional flow area from the flow orifice to the outlet passage which is at least as great as the smallest cross-sectional flow area of the flow orifice. The flow orifice in its wide open position does not restrict the cross-sectional area available for flow between the inlet and outlet passages of the valve body.

Valve especially for controlling particulate solids flow

A side by side hydrocarbon conversion-two staged stacked catalyst regeneration arrangement is provided wherein the first stage of catalyst regeneration is temperature restricted to achieve incomplete removal of carbon deposits and a second higher temperature regeneration is accomplished in an upflowing catalyst contact system under conditions to accomplish removal of residual carbon on the catalyst and produce a CO.sub.2 -rich flue gas. A special external cyclone separator arrangement may be attached to either of the second stage regeneration operation or the riser hydrocarbon conversion operation to effect separation of catalyst particles from gasiform material.

Method and apparatus for cracking residual oils

A hydrocarbon conversion-catalyst regeneration process and apparatus is described for converting residual oils and regeneration of catalyst in two separate low and higher temperature regeneration stages stacked one above the other on the same or different vertical axis to provide catalyst at a temperature above the residual feed psuedo-critical temperature. A CO rich flue gas is recovered from the low temperature regeneration stage and a CO.sub.2 rich flue gas is recovered from the higher temperature regeneration stage. The temperature of the catalyst mixed with the residual oil feed is sufficient to obtain substantially complete vaporization of the residual oil charge. A special arrangement of apparatus is provided in the lower portion of a riser conversion zone to obtain the intimate vaporization contact between residual oil feed and the high temperature catalyst charged to the riser.

A hydrocarbon conversion-catalyst regeneration process and apparatus is described for converting residual oils and regeneration of catalyst in two separate low and higher temperature regeneration stages stacked one above the other on the same or different vertical axis to provide catalyst at a temperature above the residual feed pseudo-critical temperature. A CO rich flue gas is recovered from the low temperature regeneration stage and a CO.sub.2 rich flue gas is recovered from the higher temperature regeneration stage. The temperature of the catalyst mixed with the residual oil feed is sufficient to obtain substantially complete vaporization of the residual oil charge. A special arrangement of apparatus is provided in the lower portion of a riser conversion zone to obtain the intimate vaporization contact between residual oil feed and the high temperature catalyst charged to the riser.

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Bronxville, NY, United States of America

Robert W Pfeiffer