Fluidized bed reactor
AssigneeNeste Oy
InventorMatti Hamalainen
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Abstract
The present invention relates to a fluidized bed reactor in which olefins are polymerized or copolymerized in a bed formed by particles being polymerized and fluidized with the aid of a circulating gas. In the reactor, a circulating gas is fed from a gas space above the fluidized bed into the lower part of the reactor. The lower part of the reactor includes an annular space having an defined by an upwards tapering rotating conical surface and an outer wall defined by a downwards tapering rotating conical surface.
Claims20
In an olefin polymerization fluidized red reactor reactor having a cylindrical space for polymerizing olefins in a fluidized bed formed by polymerizing polymer particles and means for supplying as a circulating gas a flow of at least one of gaseous hydrocarbon diluents and monomers into said bed of polymerizing polymer particles through a flow division plate arranged in a bottom portion of said cylindrical space, the improvement comprising:
- means defining an annular space below said flow division plate and comprising an inner wall defined by an upwards tapering rotatable conical surface, an outer wall defined by a downwards tapering rotatable conical surface and a bottom surface section, said bottom surface section being arranged between said inner wall and said outer wall and having a rounded cross-section, said means for supplying the flow of gaseous hydrocarbon diluents and/or monomers being connected to said rounded bottom surface section.
An olefin polymerization fluidized bed reactor in which olefins are polymerized or copolymerized, comprising
- an olefin fluidized bed reactor having an upper part and a lower part,
- a bed in which olefins are polymerized or copolymerized to form polyolefins, said bed means being arranged in the upper part of the reactor,
- means for supplying a circulating gas into the lower part of the reactor, the circulating gas being uniformly distributed across the cross-sectional area of the lower part of the reactor, and
- a flow division plate for separating the lower part of the reactor from the upper part of the reactor, the circulating gas passing through said flow division plate and causing the olefins to become fluidized in the upper part of the reactor by the circulating gas,
- said lower part comprising means defining an annular space, said means comprising a circular bottom surface section, an inner wall defined by an upwards tapering rotatable conical surface and an outer wall defined by a downwards tapering rotatable conical surface, said bottom surface section being arranged between said inner wall and said outer wall such that an annular space is defined between said flow division plate, said inner wall, said outer wall and said bottom surface section, said bottom surface section of said lower part comprising an annular surface having a rounded cross-section,
- said means for supplying a circulating gas being connected to said rounded cross-section annular surface of said lower part.
In a method for polymerizing or copolymerizing olefins in a fluidized bed reactor, comprising providing a bed in an upper part of a reactor in which olefins are polymerized or copolymerized to form polyolefins, circulating gas flow of at least one of hydrocarbon diluents and monomers into a lower part of the reactor and passing said circulating gas from the lower part of the reactor through separating means to the upper part of the reactor to fluidize the olefins in the upper part of the reactor, the improvement comprising the steps of:
- providing an annular space in said lower part between an inner upwards tapering rotatable conical surface and an outer downwards tapering rotatable conical surface, and
- providing an annular surface having a rounded cross-section between said outer conical surface and said inner conical surface to constitute a bottom surface section of said annular space, the gas being directed into the lower part of the reactor through the annular surface.
Dependencies are inferred from the claim text.