Control of the flow of granular polysilicon granules is effected by employing an elastomeric pinch sleeve valve. The flow control by this method is especially useful for controlling the flow of silicon seed particles and granular polysilicon product in the fluidized bed method for producing polysilicon. The flow may be stopped without gas leakage, and is suitable for use over long operating campaigns.

A process for performing a heterogeneously catalysed reaction in a three-phase reactor, where there is at least one liquid phase, at least one gaseous phase and at least one solid phase in the reactor and the reactor has at least two zones, with the reaction mixture being conveyed downward in zone 1, the reaction mixture being conveyed upward in zone 2, zones 1 and 2 being separated from one another by a dividing wall, and in that the ratio between the average catalyst concentrations in zone 2 and in zone 1 is greater than 2.

The present invention provides an apparatus for the processing of a particulate material, the apparatus comprising: a processing chamber having one or more inlets for admitting particulate material to be processed and one or more outlets for processed particulate material; the processing chamber comprising an annular treatment zone and a plurality of processing fluid inlets arranged in a base of said annular treatment zone and configured so that, in use, jets of processing fluid pass into the annular treatment zone through the plurality of processing fluid inlets to establish a spiral flow of particulate material in the annular processing zone; wherein said one or more outlets for processed particulate material are located in the base of said annular treatment zone and surrounded by said plurality of processing fluid inlets so that the spiral flow of particulate material circulates around said one or more outlets; the processing chamber further comprising means for deflecting a portion of the spiral flow of particulate material in the annular processing zone radially inwards from said spiral flow so that said particulate material leaves the processing chamber through said one or more outlets for processed particulate material.

A counter-current catalyst regenerator with at least two stages of counter-current contact along with a regenerator riser is proposed. Each stage may comprise a permeable barrier that allows upward passage of oxygen-containing gas and downward passage of coked catalyst into each stage, but inhibits upward movement of catalyst to mitigate back mixing and approximate true counter-current contact and efficient combustion of coke from catalyst. The regenerator riser may provide a passage to transport the catalyst and may serve as a secondary stage for coke combustion to provide the regenerated catalyst.

In an embodiment, a method for producing a polyolefin is provided. The method includes: contacting a first composition and a second composition in a line to form a third composition, wherein: the first composition comprises a contact product of a first catalyst, a second catalyst, a support, and a diluent, wherein the mol ratio of second catalyst to first catalyst is from 60:40 to 40:60, the second composition comprises a contact product of the second catalyst and a second diluent; introducing the third composition from the line into a gas-phase fluidized bed reactor; exposing the third composition to polymerization conditions; and obtaining a polyolefin.

An enclosure for separating and stripping an effluent containing particles includes a side wall defining an internal volume having a longitudinal axis and, inside the internal volume, a separating section and a stripping section for stripping particles downstream of the separating section relative to the circulation of the particles inside the enclosure. The enclosure includes, upstream of the stripping section or a zone of the stripping section provided with stripping elements extending through the internal cross-section of the enclosure, at least one grille extending transversely to the longitudinal axis, and the projection of a single grille or all the grilles onto a transverse plane perpendicular to the longitudinal axis covers 80 to 100% of the internal cross-section of the enclosure.

Disclosed is an antistatic agent for a metallocene olefin polymerization process and a polymerization method using the same, by which discontinuity event due to sheeting or drooling occurring in the olefin polymerization process can be effectively reduced, enabling continuous operation for a long time, and the obtained final product can be applied to various applications including food contact use. The present disclosure includes an olefin polymerization method, which comprises forming a mixture in which an antistatic agent containing diglycerol oleate is mixed with a low molecular weight hydrocarbon, supplying the antistatic agent mixture and a metallocene-based catalyst composition comprising a metallocene catalyst and aluminoxane to two or more polymerization reactors, and polymerizing one or more alpha-olefins in the presence of the antistatic agent mixture and catalyst composition.

A fluid catalytic cracking (FCC) unit for the production of hydrocarbon products includes a fluid injection system coupled to a reactor by a standpipe. The fluid injection system includes a plurality of nozzles for injecting oil feedstock into the standpipe to react with a catalyst flowing therethrough.

A multi-stage product gas generation system converts a carbonaceous material, such as municipal solid waste, into a product gas which may subsequently be converted into a liquid fuel or other material. One or more reactors containing bed material may be used to conduct reactions to effect the conversions. Unreacted inert feedstock contaminants present in the carbonaceous material may be separated from bed material using a portion of the product gas. A heat transfer medium collecting heat from a reaction in one stage may be applied as a reactant input in another, earlier stage.

A method for transitioning a gas phase polymerization reactor between metallocene catalysts is provided. The method comprises first reducing the superficial gas velocity and increasing the height of the fluidized bed within the reactor prior to stopping a feed comprising a first metallocene catalyst. The method further comprises introducing a first polymerization neutralizer to the reactor, wherein the first polymerization reactor does not comprise water, and then introducing a second polymerization neutralizer to the reactor, wherein the second polymerization neutralizer is different from the first polymerization neutralizer. After this, the method comprises purging the reactor with an inert gas and then introducing a feed comprising a second metallocene catalyst to the reactor.