Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
  • B01J8/1809—Controlling processes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
  • B01J8/24—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique
  • B01J8/26—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique with two or more fluidised beds, e.g. reactor and regeneration installations
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
  • B01J8/24—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique
  • B01J8/36—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique with fluidised bed through which there is an essentially horizontal flow of particles
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28C—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA COME INTO DIRECT CONTACT WITHOUT CHEMICAL INTERACTION
  • F28C3/00—Other direct-contact heat-exchange apparatus
  • F28C3/10—Other direct-contact heat-exchange apparatus one heat-exchange medium at least being a fluent solid, e.g. a particulate material
  • F28C3/12—Other direct-contact heat-exchange apparatus one heat-exchange medium at least being a fluent solid, e.g. a particulate material the heat-exchange medium being a particulate material and a gas, vapour, or liquid
  • F28C3/16—Other direct-contact heat-exchange apparatus one heat-exchange medium at least being a fluent solid, e.g. a particulate material the heat-exchange medium being a particulate material and a gas, vapour, or liquid the particulate material forming a bed, e.g. fluidised, on vibratory sieves
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
  • F28D13/00—Heat-exchange apparatus using a fluidised bed
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00017—Controlling the temperature
  • B01J2208/00106—Controlling the temperature by indirect heat exchange
  • B01J2208/00168—Controlling the temperature by indirect heat exchange with heat exchange elements outside the bed of solid particles
  • B01J2208/00256—Controlling the temperature by indirect heat exchange with heat exchange elements outside the bed of solid particles in a heat exchanger for the heat exchange medium separate from the reactor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00017—Controlling the temperature
  • B01J2208/00106—Controlling the temperature by indirect heat exchange
  • B01J2208/00265—Part of all of the reactants being heated or cooled outside the reactor while recycling
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00017—Controlling the temperature
  • B01J2208/00327—Controlling the temperature by direct heat exchange
  • B01J2208/00336—Controlling the temperature by direct heat exchange adding a temperature modifying medium to the reactants
  • B01J2208/00353—Non-cryogenic fluids
  • B01J2208/00371—Non-cryogenic fluids gaseous
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
  • B01J2208/00008—Controlling the process
  • B01J2208/00548—Flow

Definitions

• the present invention relates to a heat exchanger between two gases, which in particular makes it possible to limit a mixture of the gases to be treated.
• Fluidized beds behaving like liquids, it is known that they can overflow from one container to the other and put several beds in series and possibly connect the last to the first by making a circulating system.
• the motor is the difference in ventilation (and therefore density) of the successive beds.
• Patent 4,257,478 (Stendahl) describes this idea. It suffers from the complete coupling between the gas flow and the solid flows circulating between the corr.parti.uents, which greatly limits the flexibility of the system. In addition, the gas is very poorly distributed through the fluidized layer leading to stagnant areas. Patent GE- ⁇ -2,074,302 (Exxon) also takes up this idea. The configuration is characterized by a complicated design of the gas distributor and a rough control of the material flow between the compartments. Aims of the present invention An object of the present invention aims to provide a gas-gas type heat exchanger which can find many applications in the heat exchange between two gases, at least one of which can be corrosive.
• Another object of the present invention is to provide a gas-gas type heat exchanger which limits the mixing of the two gases which are subjected to heat exchange.
• Another object of the present invention is to provide an easily adjustable heat exchanger with regard to operating temperatures and flow rates, under optimal conditions.
• Another object of the present invention is to provide a heat exchanger of the aforementioned type of very simple and robust construction.
• An additional aim of the present invention is to provide a heat exchanger which takes advantage of the principle of communicating fluidized beds.
• Another object of the present invention consists in carrying out in a single simple and therefore economically attractive device, the coupled operations' heat exchange and pollution control of at least one az. Description of the characteristic elements of the invention
• the gas-gas type heat exchanger using the principle of interconnected fluidized beds is characterized in that it consists of a vertical cylindrical or polygonal tubular container divided vertically and radially with at least four adjacent compartments communicating with each other,
• each compartment contains a fluidized bed which comprises a solid material suspended by one of the hot or cold gases in ⁇ tervenant in the heat exchange; in that, in the direction of circulation of the fluidized solids, a fluidized bed at high speed is followed by a fluidized bed at low speed and this is followed by a fluidized bed at high speed, a fluidized bed at high speed being able to overflow from above into the next low speed fluidized bed and a low speed fluidized bed communicating from below with the next high speed fluidized bed; and in that it comprises at least one bypass circuit with adjustable flow rate which makes it possible to recycle the gas leaving in the fluidization of one of the fluidized beds towards at least one of the fluidized beds.
• the compartments all have an identical section. Alternatively, a smaller section can be provided for the low-speed fluidized bed compartments.
• the device of the invention comprises two bypass circuits, a first of which recycles part of the hot gases leaving the bottom of the hot compartment at high speed fluidized bed or in the hot compartment with a low-speed fluidized bed and the second recycles part of the cold gases leaving the bottom of the cold compartment with a high-speed fluidized bed or in the cold compartment with a low-speed fluidized bed.
• the exchanger according to the present invention has a particularly compact construction and simple installation. It suffices to provide corrosion-resistant materials for the constituent elements such as the external wall of the reactor and the partition walls. These elements are very simple in construction and therefore inexpensive.
• the compact arrangement of the exchanger according to the present invention also promotes good thermal exchange between the hot gas and the cold gas, the exchange being able to be carried out, on the one hand, through partition walls of the hot part and the cold part and, on the other hand, using the solid matter kept in suspension by the gases, which circulate from one part to the other, passing from a so-called hot part to a so-called cold part.
• the gases are separated since the hot part is separated from the cold part by partitions which have only one opening at their lower part for the circulation of solid materials.
• the injection of the fluidization gases can be arranged beyond said openings.
• submerged more sophisticated communication orifices in which the flow of solid is regulated by a low flow of make-up gas (constituted by one of the two main gases or a third gas as the case may be). In this way, the decoupling between solid flow and main gas flows is improved; if the make-up gas is a third gas, the two main gas flows are completely avoided.
• This configuration can be very advantageous if one of the gases is toxic or
• the particular configuration is chosen so as to be able to gradually regulate the flow rate of transferred solid.
• Such a bypass circuit makes it possible in particular, by adjusting the flow rate passing through it, to adjust the temperature level prevailing in the corresponding fluidized beds. According to a variant of the present invention, the
• D solids suspended in the flui ⁇ disation gases may at least partially consist of materials which can interact chemically or physically with the gases which hold them in suspension, with a view to cleaning them up, for example. solid materials
• 3 ° may consist of chemical reagents, active catalytic substances supported on suitable conventional support materials or chemical or physical absorbents, in particular pulverulent masses making it possible to fix these aerosols, droplets and
• FIG. 1 is a schematic vertical section of the exchanger according to the invention
• FIG. 2 represents a schematic section of the device according to FIG. 1, at level A-A, and
• FIG. 3 is a diagram of the exchanges of materials and of gas flows
• compartment 1 If the fluidization speed of compartment 1 is higher than that applied to compartment 2, the equilibrium level of the bed will be higher than that of compartment 2. If the partition 4 is lowered separating the two compartments so to allow an overflow, the two levels are balanced and cause a circulation of the solid according to the arrows.
• FIG. 1 and 2 A particularly preferred embodiment of the invention is shown in Figures 1 and 2.
• the exchanger com ⁇ carries four compartments 1, 2, 3, 4, two of which (1, 2) form the cold part and the other two (3 , 4) the hot part.
• the compartments are brought to different fluidization speeds which cause the following circulation: the solid particles pass from compartment 1 to compartment 2 by overflow because the fluidization speed of 1 is greater than that of 2; the solid particles pass from compartment 2 to 3 through the bottom 5, from 3 to 4 by overflow since the fluidization speed of 3 is greater than that of 4 and from 4 to 1 through the bottom 6.
• the hot gas supplied at 10 to suspend the solid matter passes through the compartments 3 and 4 by yielding part of its heat energy to the cold gas and leaves 1 "exchanger at 8.
• a bypass circuit 15 adjustable by means of a valve 17 makes it possible to recycle part of the hot gases at the bottom of one of the hot compartments 3 or 4, preferably compartment 3 carrying the fluidized bed at high speed This arrangement makes it possible to easily adjust the temperature level of the system. Circulation is ensured by a circulation fan 13.
• the cold gas is evacuated through line 7 and the hot fluidizing gas through line 8 which allows them to be separated.
• the device of the invention advantageously comprises a supply 13 of solid materials in the hot or cold part p r a hopper and a worm. It is understood that the supply can be done by any means known per se, for example by a butterfly valve or an annex fluidized bed.
• Cn can also provide for a withdrawal of solid matter, possibly after chemical reaction, by the bottom (not shown). These can be sieved and re-injected into the hot part or the cold part to play the role of thermal flywheel.
• the device of the present invention may also include a cyclone system (not shown in the figures) or any other system for filtering gases at high temperature to purify the gas and recycle the fine dust carried away.
• a cyclone system not shown in the figures
• any other system for filtering gases at high temperature to purify the gas and recycle the fine dust carried away.
• Gas distributors are those commonly used in simple fluidized beds, such as, for example, perforated plates, bell plates, perforated tubes, etc. This type of configuration is well known and gives all the guarantees of reliability. Its construction is very easy, which constitutes an important advantage.
• the regulation can be carried out in a practical manner as indicated in FIG. 2 while ensuring a large and regular circulation of the flow of solid materials.
• the regulating device includes the measurement of differential pressure drops to control a motorized valve that can be mounted on the conduit 11 and / or the conduit 12 (only the embodiment of a motorized valve on the circuit 12 is shown in the figure 2).
• FIG. 2 it is possible to regulate the flow of solids circulating between the hot part and the cold part by mounting a localized differential pressure sensor (20 and 2 Q ′) in at least one submerged orifice (5) in order to control by a motorized valve (24), the flows supplying at least one high-speed compartment (3).
• the gas flows are shown diagrammatically by continuous lines and by broken lines, the exchanges of material between a cold part 31 and a hot part 32.
• the main direction of circulation of the gases is marked by a simple arrow and the possible gas bypass circuits are indicated by a double arrow.
• the various control valves 24 that can be mounted in the bypass circuit are also shown.
• FIGS. 4A to 4E various configurations of the submerged orifices 5 ′ for communication are shown, which in particular in the case of FIGS. 4B, 4C, 4D and 4 ⁇ are configurations in J, L, U and in V allows ⁇ attempt to regulate the flow of solid transferred using a
• the device of the invention has greater compactness and better
• Heat transfer takes place through the circulation of solid particles and through the partition wall between the hot and cold parts.
• An application of the exchanger according to the invention is in the field of recovery of the heat energy contained in the waste gases from glass furnaces. Such a gas leaves the oven at 1400 ° C, passes through a
• the gas leaving the oven at 1400 ° C is brought to 535 ° C in the conventional regenerator and 302 ° C in the exchanger according to the invention before being evacuated in a chimney.
• Ambient air at 20 ° C is heated to 251 ° C in the exchanger according to the invention and brought to 1161 ° C in the classic regenerator. This results in a significant improvement in the energy balance of the installation.
• the bed plays the role of mass making it possible to fix or capture the aerosols, the droplets and the very fine particles present in the gas.
• .o gas distributor is a distributor quite classi ⁇ that, as used for fluidized beds and that the section of the device remains constant with height, above said distributor.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)

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ID=19730663

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• 1986
  • 1986-03-12 LU LU86352A patent/LU86352A1/fr unknown
• 1987
  • 1987-03-11 EP EP19870902037 patent/EP0298980A1/de not_active Withdrawn
  • 1987-03-11 WO PCT/BE1987/000004 patent/WO1987005687A1/fr not_active Application Discontinuation
  • 1987-03-11 JP JP50183787A patent/JPH01501767A/ja active Pending

Non-Patent Citations (1)

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