摘要:
The present invention provides a system and method for preparing high-purity vanadium pentoxide powder. Industrial grade vanadium pentoxide is converted to vanadium oxytrichloride by low temperature fluidizing chlorination, wherein chlorinating gas is preheated via heat exchange between fluidizing gas and chlorination flue gas, and an appropriate amount of air is added to enable a part of carbon powder to combust so as to achieve a balanced heat supply during the chlorination, thereby increasing the efficiency of chlorination and ensuring good selectivity in low temperature chlorination. The vanadium oxytrichloride is subjected to purification by rectification, ammonium salt precipitation and fluidized calcination, thereby obtaining high-purity vanadium pentoxide, wherein the ammonia gas produced during calcination is condensed and then recycled for ammonium salt precipitation. The system and method have advantages of favorable adaptability to a raw material, less pollution, low energy consumption in production and low operation cost, stable product quality and so on, and are suitable for large-scale production of high-purity vanadium pentoxide powder with a purity of above 4N.
摘要:
This present invention relates to a reaction device for preparing light olefins from methanol and/or dimethyl ether, and more specifically relates to a reaction device for preparing light olefins from methanol and/or dimethyl ether, which mainly comprises a dense phase fluidized bed reactor (2), a cyclone separator (3), a stripper (5), a lift pipe (7), a dense phase fluidized bed regenerator (10), a cyclone separator (11), a stripper (13), and a lift pipe (15), wherein the dense phase fluidized bed reactor (2) is separated into n (n‰¥2) secondary reaction zones by a material flow controller (17), and the dense phase fluidized bed regenerator (10) is separated into m (m‰¥2) secondary regeneration zones by the material flow controller (17). The use of the reaction device of this present invention solves the problems in the prior art that the distribution of carbon deposition on a catalyst is non-uniform and the selectivity for the light olefins is relatively low.
摘要:
Provided in the present invention are an olefin polymerization apparatus and an olefin polymerization process. The following operations and effects can be realized by the apparatus or method provided in the present invention: the gas material discharged from the polymerization reactor is condensed, after the gas-liquid separation, the resulting gas portion is recycled to the reactor to form a circulation loop; the condensate can be selectively introduced to the polymerization reactor, in order to achieve the free switch between the homopolymerization reaction and the copolymerization reaction or between different copolymerization reactions, and at the same time the condensate can absorb the heat generated by the reaction. By using the apparatus and method provided in the present invention, polyolefin products having excellent mechanical properties and processability can be prepared as needed.
摘要:
A device for injecting fluids into the free area of a rotating fluidised bed in a fixed cyclone chamber and methods using this device comprising a device for the tangential injection of secondary fluids making it possible to form rotating rings of fluids in said free area along the sidewalls of said cyclone chamber, in order to move away from said sidewalls and accelerate the speed of rotation of the fluid streams exiting along said sidewalls and thus improve the discharge of the solid particles entrained by said exiting fluid streams.
摘要:
The present invention relates to a process for the continuous preparation of a polyolefin in a reactor from one or more α-olefin monomers of which at least one is ethylene or propylene, wherein the reactor comprises a fluidized bed, an expanded section located at or near the top of the reactor, a distribution plate located at the lower part of the reactor and an inlet for a recycle stream located under the distribution plate wherein the process comprises—feeding a polymerization catalyst to the fluidized bed in the area above the distribution plate—feeding the one or more α-olefin monomers to the reactor—withdrawing the polyolefin from the reactor—circulating fluids from the top of the reactor to the bottom of the reactor, wherein the circulating fluids are compressed using a compressor and subsequently cooled using a heat exchanger to form a cooled recycle stream comprising liquid, and wherein the cooled recycle stream is introduced into the reactor using the inlet for the recycle stream wherein a part of the cooled recycle stream is drawn to form a liquid comprising stream, wherein the liquid comprising stream is introduced into the expanded section during at least part of the polymerization process, and wherein the liquid comprising stream is brought into contact with at least part of the interior surface of the expanded section.
摘要:
The invention relates to a fluidized bed reactor for producing polycrystalline silicon granulate, comprising a reactor container (1), a reactor pipe (2), and a reactor base (15) within the reactor container (1). The reactor pipe (2) consists of a main part and a surface coating, and an intermediate casing (3) is located between the outer wall of the reactor pipe (2) and the inner wall of the reactor container (1). The fluidized bed reactor further comprises a heating device (5), at least one base gas nozzle (9) for supplying fluidizing gas, at least one secondary gas nozzle (10) for supplying reaction gas, a supply device (11) for supplying silicon seed particles, a removal line (14) for polycrystalline silicon granulate, and a device for discharging reactor exhaust gas (16). The invention is characterized in that the main part of the reactor pipe consists of a base material with an ash content of
摘要:
A fluid catalytic cracking apparatus and process is disclosed, providing for efficient conversion of heavy hydrocarbon feeds to light olefins, aromatics, and gasoline. A countercurrent flow reactor operating in bubbling or turbulent fluidization regimes is integrated with a fluid catalytic cracking riser reactor. A heavy hydrocarbon feed is catalytically cracked to naphtha and light olefins in the riser reactor, a co-current flow reactor. To enhance the yields and selectivity to light olefins, cracked hydrocarbon products from the riser reactor, such as C4 and naphtha range hydrocarbons, may be recycled and processed in the countercurrent flow reactor. The integration of the countercurrent flow reactor with a conventional FCC riser reactor and catalyst regeneration system may overcome heat balance issues commonly associated with two-stage cracking processes, may substantially increase the overall conversion and light olefins yield, and/or may increases the capability to process heavier feedstocks.