32 results about "Annular fluidized bed" patented technology

A method is provided for treating black liquor particularly derived from non-wood pulp, by heating with an alkaline earth metal oxide in a toroidal fluidised bed reactor at a temperature of above 650° C. The method may be used alone or as part of a method of converting graminaceous raw material to pulp for paper or board, said method comprising (a) digesting said raw material with a white liquor based on sodium hydroxide and further comprising calcium hydroxide in an amount effective to substantially convert silica of said raw material to calcium silicate; (b) recovering pulp and black liquor substantially free of uncombined silica; (c) heating the black liquor in a fluidized bed reactor containing calcium oxide for catalysing conversion of organic content of said black liquor to gas and for providing recovered solids including sodium values of said white liquor and calcium oxide; and regenerating said white liquor using said recovered solids. The use of the above mentioned white liquor permits treatment of wheat straw, rice straw and other high-silica materials without resulting in a black liquor that is difficult to treat.

The present invention relates to a method and a plant for producing low 15 temperature coke, in which granular coal and possibly further solids are heated to a temperature of 700 to 1050° C. in a fluidized-bed reactor (2) by means of an oxygen-containing gas. To improve the utilization of energy it is proposed to introduce a first gas or gas mixture from below through at least one gas supply tube (3) into a mixing chamber region (8) of the reactor (2), the gas supply tube (3) being at least partly surrounded by a stationary annular fluidized bed (6) which is fluidized by supplying fluidizing gas. The gas velocities of the first gas or gas mixture and of the fluidizing gas for the annular fluidized bed (6) are adjusted such that the Particle-Froude-Numbers in the gas supply tube (3) are between 1 and 100, in the annular fluidized bed (6) between 0.02 and 2 and in the 25 mixing chamber (8) between 0.3 and 30.

The invention discloses an external catalytic cracking heater with pre-distributed particles and is suitable for a catalytic cracking device in an oil refinery. The external catalytic cracking heater is characterized in that a plurality of unit type heat exchange tubes (6) with independent water inlets and water outlets are arranged inside an external heater (4); the heat exchange tubes (6) extend from the top to the bottom of the external heater (4), and the bottom of the external heater is provided with a guide bracket (2) which limits transverse swing of the heat exchange tubes (6); the lower parts of the heat exchange tubes (6) are immersed in a dense-phase fluidized bed (11) at the bottom of the external heater (4); hot catalyst particles entering from a catalyst inlet (10) in the middle of the external heater (4) enter an annular fluidized bed (17), and the hot particles uniformly flow into the dense-phase fluidized bed (11) from the upper edge of a side wall (15) on the inner side of the annular fluidized bed (17) or an overflow notch (19) formed in the side wall (15) on the inner side by utilizing the particle pre-distribution function of the annular fluidized bed (17); the hot particles are contacted and cooled with the side wall of the heat exchange tubes (6) and flow out of a catalyst outlet (1) at the bottom of the external heater (4) in the dense-phase fluidized bed (11); and fluidized gas in the dense-phase fluidized bed (11) is introduced from a bottom gas distributor (2), and the fluidized gas which passes through the dense-phase fluidized bed (11) and the fluidized gas in the annular fluidized bed (17) are mixed to enter a dilute phase space of a catalytic cracking device regenerator through a gas outlet (7) formed on the top of the external heater (4).

The invention relates to an annular fluidized bed separator of a particle mixture. The upper end of a center lifting pipe extends into an annular fluidized bed by a certain height, so that the annular fluidized bed is divided into an annular area at the lower part and a cylindrical area at the upper part; an air inlet and a wind distribution plate are respectively arranged at the bottoms of the center lifting pipe and the annular fluidized bed; a feed port is formed in the bottom of the center lifting pipe; a heavy particle outlet is formed in the bottom of an annular area of the annular fluidized bed, and is connected with a heavy particle collecting tank; and an airflow outlet at the top of the annular fluidized bed is connected to a light particle collecting tank by a cyclone separator. The particle mixture is quickly fluidized in the center lifting pipe for primary dispersion, and is ascended along with air currents to enter the annular fluidized bed for secondary dispersion. The annular fluidized bed separator can continuously and quickly perform high-efficiency separation for light and heavy particle mixtures under the condition of normal temperature or high temperature. The annular fluidized bed separator can be coupled with a circulating fluidized bed reactor system, and can continuously and stably operate.

The invention relates to a tubular bilateral fluidized bed rapid pyrolysis device, and belongs to the technical field of utilization of renewable energy sources. The rapid pyrolysis device comprises an inner pipe, an outer pipe, a supporting sleeve, an annular air distribution plate, a round air distribution plate, a buffer sleeve, a carrier gas uniform distributor and a spiral plate heat exchanger which are coaxially arranged from top to bottom. According to the rapid pyrolysis device disclosed by the invention, the characteristic of high heat transfer efficiency of the fluidized bed and the wall surface of a container is utilized, the fluidized bed in the inner pipe is used as a reaction zone, an annular fluidized bed is additionally at the periphery as a heating zone, and high-temperature flue gas after combustion is used as fluidized carrier gas, so that the comprehensive heat transfer of a reactor is increased, heat absorbed by biomass pyrolysis can be supplemented, and the whole structure is more compact; meanwhile, the counter-flow type spiral plate heat exchanger is added, so that combustion flue gas waste heat can be fully utilized. By changing the flow of two branches in the rapid pyrolysis device, temperature regulation can be realized on the premise that the unchanged fluidizing gas speed of the reaction zone is ensured, and biomass pyrolysis reactions under different technological conditions can be adapted.

The invention provides a ring-shaped fluidized bed reactor, belonging to the technical field of fluidized bed reactors. The ring-shaped fluidized bed reactor comprises a top cover, a reactor outer shell, a bottom shell, a support, a combustion chamber, an air distributing plate and an air distributing cabin partition and also comprises circulatory speed increasing pipes and an air distributing cabin, wherein peripheral equipment comprises a cyclone separator and a fan; the lower end of the reactor outer shell is provided with the air distributing plate and then is fixedly connected with the bottom shell; the combustion chamber is sheathed in the reactor outer shell; the axis of the reactor outer shell and the axis of the combustion chamber are consistent, and a ring-shaped reaction area is formed between the reactor outer shell and the combustion chamber; the circulatory speed increasing pipes are uniformly distributed in the combustion chamber, the upper ends of the circulatory speed increasing pipes are communicated with the ring-shaped reaction area, and the lower ends of the circulatory speed increasing pipes penetrate through the air distributing plate; the bottom shell is internally provided with the air distributing cabin partition which is internally provided with the air distributing cabin; and bending pipes on the circumferential surface of the air distributing cabin are communicated with the lower ends of the circulatory speed increasing pipes. The ring-shaped fluidized bed reactor provided by the invention has the advantages that the combustion chamber is arranged in the reactor outer shell and is internally provided with the circulatory speed increasing pipes, so that the space can be saved, the heat loss can be reduced, meanwhile the internal circulation of fluid is enhanced, and the heat transferring efficiency and the reaction conversion rate of the reactor are increased.

The invention relates to a process for the production of metal oxides from metal compounds, in particular metal hydroxides or metal carbonates, in which the metal compounds are fed into a reactor (25) with a fluidized bed, where they are combusted by fuel It is heated to a temperature of 650-1150° C. to generate metal oxides, and the invention also relates to a corresponding device. In order to improve energy utilization, it is proposed to introduce the first gas or gas mixture from below into the mixing chamber (20) of the reactor (25) through the gas supply pipe (26), which is at least partially fixed by supplying fluidized gas The annular fluidized bed (27) is surrounded by adjusting the gas velocity of the first gas or gas mixture and the fluidizing gas for the annular fluidized bed (27), so that the particle Froude number in the gas supply pipe (26) is 1- 100, the Froude number of particles in the annular fluidized bed (27) is 0.02-2, and the Froude number of particles in the mixing chamber (20) is 0.3-30.

The invention provides a circulating accelerating pipe used in an annular fluidized bed reactor, which comprises a 90-degree elbow pipe, a riser pipe, a reducing joint, a three-way pipe, a straight-through pipe joint, a connecting pipe, a first nut, a conical pipe, an O-shaped ring, a gasket and a second nut. The upper end of a main pipe of the three-way pipe is vertically successively connected with the reducing joint, the riser pipe and the 90-degree elbow pipe, the lower end of the main pipe of the three-way pipe is vertically successively connected with the straight-through pipe joint and the connecting pipe, the straight-through pipe joint is fixedly connected with the connecting pipe via the first nut, the conical pipe is mounted in the straight-through pipe joint, the lower end of the conical pipe is clamped in a sunken table at the lower end of a center through hole of the straight-through pipe joint, the top end of the conical pipe is higher than the axis of a side branch pipe of the three-way pipe, the O-shaped ring is disposed between the lower end surface of the conical pipe and the upper end surface of the connecting pipe, the lower end of the connecting pipe is a spraying nozzle, and the side branch pipe of the three-way pipe is an air inlet of the circulating accelerating pipe. The conical pipe is added in the circulating accelerating pipe, so that fluid circulation can be accelerated, and the conversion rate of objective products is improved.

The invention relates to an indirectly heated fluidized bed dryer (1) for drying wet, fine-grained bulk materials. The fluidized bed dryer (1) comprises a housing (2) having a gassing floor (6) having heat exchanger fixtures extending above the gassing floor (6) and at least one discharge device below the gassing floor (6) for the dried bulk material. The fluidized bed dryer (1) according to the invention is characterized in that the usable flow cross section of the housing (2) in the area of the heat exchanger fixtures decreases over the height of the heat exchanger fixtures in the flow direction of the fluidizing material, as the cross-sectional area of the housing remains the same. In this manner, an unallowable expansion of the stationary fluidized bed is reliably prevented.

A device with an annular spouted fluidized bed and an operating method therefor are claimed. The device according to the invention can be used for carrying out the majority of technical processes carried out in fluidized bed devices, inter alia for purifying gas mixtures, drying materials, pyrolysis, gasification, and combusting solid fuels such as industrial waste, agricultural waste, MSW, coal,sewage sludge, and aerobic and anaerobic digestion reactor waste, and also for carrying out other chemical reactions carried out in a fluidized bed. A reaction chamber of the present device with a rotating annular spouted fluidized bed has, throughout at least a part of its height, a downwardly tapering funnel shape with a stepped interior surface. The shape of the reaction chamber, together withthe tangential admission thereto of fluidized and other gases, makes it possible to create, in the reaction chamber, an adjustable toroidal fluidized bed, in which the rate of rotation of the particles of the material undergoing treatment can be adjusted in both the horizontal and vertical planes, and also makes it possible to control the dwell time of particles of different sizes in the reactionzone, the intensity with which materials are treated, and other process parameters.

A plant for the heat treatment of solids containing iron oxide. The plant includes a reactor including a fluidized bed reactor. The reactor includes a gas supply system disposed in the reactor, a stationary annular fluidized bed which at least partly surrounds the gas supply system, and a mixing chamber. The gas supply system is configured so that gas flowing through the gas supply system entrains solids from the stationary annular fluidized bed into the mixing chamber.

The invention relates to a device for removing moisture from granular solid food, comprising: a casing (9); an orifice (2) separating the casing (1) into two cavities (3, 4); (2) Gas inlets (5,6) below; outlets (8) on the orifice plate (2) with removable plugs (9); heaters (15,18) for heating the gases. The invention also relates to a method for removing moisture from small solid particles by heat treating the particles in an annular fluidized bed for a specified period of time.