The present invention relates to a process for polymerizing at least one olefin in gas phase in a fluidized bed in a polymerization reactor having a top zone of a generally conical shape as such that the equivalent cross-sectional diameter is monotonically decreasing with respect to the flow direction of the fluidization gas, a middle zone in direct contact with and below said top zone of a generally cylindrical shape and a bottom zone in direct contact and below said middle zone and of a generally conical shape as such that the equivalent cross-sectional diameter is monotonically increasing with respect to the flow direction of the fluidization gas, comprising the steps of: a) introducing a first stream of fluidization gas into the bottom zone; b) polymerizing at least one olefin in the presence of a polymerization catalyst in the fluidized bed formed by particles of a polymer of the at least one olefin suspended in an upwards flowing stream of the fluidization gas in the middle zone; c) withdrawing a second stream comprising the fluidization gas and optionally particles of a polymer of the at least one olefin from the top zone; characterized in that the temperature of the particles of the polymer of the at least one olefin in the fluidized bed (T.sub.PP) does not exceed 120% of the operating temperature set point (T.sub.S) of the polymerization reactor, wherein T.sub.PP and T.sub.S are both given in ? C., and the use of said process for polymerizing an olefin homo- or copolymer having a narrow particle size distribution.

Systems and methods for producing light olefins wherein a feed stream comprising naphtha is flowed into a reaction unit comprising a fast fluidized bed reactor coupled to and in fluid communication with a riser reactor. The fast fluidized bed reactor comprises baffles therein to minimize backmixing therein to maximize the production of light olefins. The effluent from the fast fluidized bed reactor is further flowed to the riser reactor. The lift gas, which can comprise nitrogen, methane, flue gas, or combinations thereof, is injected in the reaction united via a sparger. Effluent of the riser reactor is separated in a product separation unit to produce a product stream comprising light olefins and spent catalyst. Spent catalyst is further stripped by a stripping gas comprising methane, nitrogen, flue gas, or combinations thereof. Stripped spent catalyst is regenerated to produce regenerated catalyst, which is subsequently flowed to the fast fluidized bed reactor.

A heat removal tube set, and application of the same for controlling the temperature of a fluidized bed reactor and for producing an unsaturated nitrile are provided. The heat removal tube set has at least one first heat removal tube and at least one second heat removal tube, wherein the ratio of the total circumference Lb of the outer contours of all of the straight pipes b of the second heat removal tube on the cross section to the total circumference La of the outer contours of all of the straight pipes a of the first heat removal tube on the cross section is greater than 1 and less than 1.25. When the first heat removal tube and the second heat removal tube are switched coordinatively in a paired manner, the reaction temperature can be maintained substantially constant.

A heat removal tube set, a method for controlling reaction temperature using the heat removal tube set, and a method for producing an unsaturated nitrile are provided. The heat removal tube set has at least one first heat removal tube and at least one second heat removal tube. The number of all straight pipes a of the first heat removal tube is the same as that of all straight pipes b of the second heat removal tube. The ratio of the total circumference Lb of the outer contours of all of the straight pipes b of the second heat removal tube on the cross section to the total circumference La of the outer contours of all of the straight pipes a of the first heat removal tube on the cross section is 1.25-2. When the first heat removal tube and the second heat removal tube are switched coordinatively in a paired manner, a fine adjustment of the reaction temperature can be realized.

The invention relates to a fluidized bed installation (1), comprising at least two chambers (2, 3, 4), wherein each chamber (2, 3, 4) has a main body (5) and a gas inlet (6) and a gas outlet (7), wherein each main body (5) has an inlet (8) and an outlet (9) for a solid (19), wherein the inlet (8) of a first chamber (2) is connected to a feed (10) of the fluidized bed installation (1), the outlet (9) of the first chamber (2) is connected to the inlet (8) of a second chamber (4), and the outlet (9) of the second chamber (4) is connected to a discharge (11) of the fluidized bed installation (1), and wherein a valve (12) is arranged between two connected chambers (2, 3, 4) and/or at the feed (10) and/or at the discharge (11) such that either continuous operation or semi-continuous operation of the fluidized bed installation (1) is enabled.

An apparatus used in a fluidized reaction process comprising a vessel; a riser housed within the vessel; and a plurality of angled guide supports, wherein each guide support comprises an tubular section having a first end and a second end; a first hinge wherein a first end of the first hinge is connected to the first end of the tubular section, a second hinge wherein a first end of the second hinge is connected to the second end of the tubular section, wherein a second end of the first hinge is connected to an inside surface of the vessel and a second end of the second hinge is connected to the riser guide is provided.

A bio-reforming reactor receives biomass to generate chemical grade syngas for a coupled downstream train of any of 1) a methanol-synthesis-reactor train, 2) a methanol-to-gasoline reactor train, and 3) a high-temperature Fischer-Tropsch reactor train, that use this syngas derived from the biomass in the bio-reforming reactor. A renewable carbon content of the produced gasoline, jet fuel, and/or diesel derived from the coupled downstream trains of any of 1) the methanol-synthesis-reactor train, 2) the methanol-to-gasoline reactor train, or 3) the high-temperature Fischer-Tropsch reactor train are optimized for recovery of renewable carbon content to produce fuel products with 100% biogenic carbon content and/or fuel products with 50-100% biogenic carbon content. A carbon-dioxide gas feedback loop cooperates with a CO2 separation unit to supply a fraction of the CO2 gas that is removed from the chemical grade syngas produced from the reactor output of the BRR to supply extracted CO2 gas to the biomass feed system.

One or more embodiments relate to a contactor/separator vessel for reacting with fine particles. The contractor/separator vessel includes a spouted bed containing fine Geldart class C particles; and an additional spoutable media to facilitate spouting of the fine Geldart class C particles in order to improve mixing, gas-solid contact/separation.

A fluidized bed reactor includes a gas distributor, a tapered section above the gas distributor, and an expanded head above the tapered section. The gas distributor defines a plurality of inlets surrounding a product withdrawal tube, which extends away from the fluidized bed reactor. The fluidized bed reactor is useful in a process for fluidizing relatively large particles, such as Geldart Group B particles and/or Geldart Group D particles, where said particles are in a bubbling fluidized bed residing, in whole or in part, in the tapered section. The fluidized bed reactor and process may be used for manufacturing polycrystalline silicon.

Disclosed is a method for starting up fluidized reaction apparatus that is used for producing lower olefins from methanol or/and dimethyl ether. Said method includes after heating the catalyst bed of circulating fluidized catalytic reaction apparatus to above 200 C. or 300 C. by using a starting-up auxiliary heat source, feeding methanol or dimethyl ether raw materials to a reactor, whereby heat released by the reaction makes the temperature of the reaction system apparatus increase quickly to a designed temperature, consequently making the system reach normal operation state rapidly. Said method is suitable for starting up an exothermic fluidized catalytic reaction apparatus and can simplify the apparatus and operation, accordingly lowering the cost.