AT521611A4 - Fluidized bed reactor with buffer stores - Google Patents

Abstract

Fluid bed system (1) and method comprising: - a fluid bed channel (5), - a first storage tank (2) for a solid bed (4), - a second storage tank (3) for solid bed (4), the second storage tank (3) is connected to the first storage tank (2) via the fluidized bed channel (5), - a fluidization device, in particular a nozzle base (6) extending from the first storage tank (2) via the fluidized bed channel (5) to the second storage tank (3), for introduction a fluidizing gas in the fluidized bed channel (5), in the first storage tank (2) and in the second storage tank (3), - a first valve (10) for setting a first pressure (p1) of the fluidizing gas in the first storage tank (2), - A second valve (11) for setting a second pressure (p2) of the fluidizing gas in the second storage container (3), so that by setting a pressure difference between de In the first pressure (p1) in the first storage container (2) and the second pressure (p2) in the second storage container (3) the solid bed (4) in the fluidized state from the first storage container (2) via the fluidized bed channel (5) to the second storage container (3) is conveyable.

Description

The invention relates to a fluidized bed system comprising:

- a fluidized bed channel,

a first storage container for a solid bed,

- A second storage container for the solid bed, the second storage container being connected to the first storage container via the fluidized bed channel.

The invention further relates to a method for conveying a solid bed from a first storage container via a fluidized bed channel to a second storage container.

In the prior art, fluidized beds have long been used for the treatment and handling of solid beds.

A bed of solid particles is referred to as a fluidized bed, which is brought into a fluidized state by an upward flow of a fluidizing gas. In the case of such fluidized bed modules, a nozzle base is provided through which the fluidizing gas is introduced into the reactor space from a wind box below, in order to generate the fluidized bed there by swirling up the solid bed (cf. AT 515 810 A1).

For example, fluidized bed heat exchangers can be realized in this way, in which heat exchanger elements are immersed in the fluidized bed, in order to heat or cool the fluidized solid by heat exchange with the working medium within the heat exchanger elements.

From AT 515 683 A1 it is also known to provide a horizontally flowing stationary fluidized bed made of bulk material, in which a cover plate which limits the rising fluidizing gas flow is provided above the fluidized bed. At least one nozzle is arranged in the cover plate, with which a backflow of the fluidizing gas stream can be generated.

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As a result, an air cushion can be formed above the fluidized bed, which shows the level of the fluidized bed in it

Depressed area. In this way, excessively large level differences can be reduced.

A disadvantage of the prior art is the conveyance of the bulk material from the storage containers into the fluidized bed channel. For this purpose, pneumatic conveyance has been provided on the one hand, which, however, disadvantageously entails very high gas speeds and thus a high auxiliary energy requirement. The transport (exhaust) air causes high thermal losses when transporting hot particles. Another disadvantage is that the required solid-gas separation, for example with the aid of a cyclone, is complex and in many cases is not completely successful. On the other hand, mechanical particle conveyors were used. On the one hand, these have high investment costs and on the other hand increase the risk of failure of the systems.

The object of the invention is to alleviate or eliminate at least individual disadvantages of the prior art. The invention therefore has the particular aim of creating a fluidized bed system and a method of the type mentioned at the outset with which the conveying of the bulk material into the fluidized bed channel is improved.

This object is achieved by a fluidized bed system with the features of claim 1 and a method with the features of claim 19. Preferred embodiments are specified in the dependent claims.

The fluidized bed system according to the invention is characterized by

a fluidization device, in particular a nozzle base extending from the first storage tank via the fluidized bed channel to the second storage tank, for introducing a fluidizing gas into the fluidized bed channel, into the first storage tank and into the second storage tank,

a first valve for setting a first pressure of the fluidizing gas in the first storage container,

- A second valve for setting a second pressure of the fluidizing gas in the second storage tank, so that by setting a pressure difference between the first pressure in the first storage tank and the second pressure in the second storage tank, the solid bed in the fluidized state from the first storage tank via the fluidized bed channel is conveyable to the second storage container.

Advantageously, therefore, a flow of the bulk material in the fluidized state, which is preferably at least in sections substantially horizontal, can be generated from the first storage container along the fluidized bed channel into the second storage container (or in the opposite direction). With the aid of the first valve, the first pressure of the fluidizing gas in the first fluidizing gas space can be set to a value different from the atmospheric pressure. Accordingly, the second pressure of the fluidizing gas in the second fluidizing gas space can be set to a value different from the atmospheric pressure with the aid of the second valve. By setting a suitable pressure gradient between the first and second fluidizing gas spaces by means of the first and second valves, the bulk material can be conveyed in the fluidized state from the first storage tank via the fluidized bed channel to the second storage tank. As the first and / or second valve, pressure control valves known per se are used in particular in the prior art. Advantageously, the particle exchange between the first storage container / 45 and the second storage container can therefore be accomplished without a separate pneumatic or mechanical particle conveyor. This enables a particularly energy-efficient fluidized bed system to be created, which is characterized by low wear and low maintenance. In a preferred application, the fluidized bed system serves as a fluidized bed heat exchanger (or fluidized bed regenerator). It is advantageous here that the capacity of the fluidized bed regenerator can be increased or its capacity and capacity can be decoupled. The performance is determined by the heat exchanger surface, while the capacity is determined by the size of the storage tank. The storage capacity or cycle duration can therefore be flexibly adapted for a given output. The embodiment according to the invention also offers significant advantages in other applications of the fluidized bed system, for example for the treatment of particulate solids. In particular, an essentially continuous process can be achieved instead of a batch or batch process.

The first storage container preferably has a first ceiling to which the first valve is connected. The second storage container preferably has a second ceiling to which the second valve is connected.

According to a preferred embodiment, the first storage container has a first funnel section, which is connected to the fluidized bed channel via a first through opening on the underside of the first funnel section, and / or the second storage container has a second funnel section, which connects via a second through opening on the underside of the second funnel section is connected to the fluidized bed channel. The first funnel section is particularly preferably arranged at a lower end of the first storage container and / or the second funnel section is arranged at a lower end of the second storage container. Advantageously, the first and / or second storage container can thereby be completely or at least largely emptied, since, owing to the funnel shape, no or only a small amount after the emptying

Amount of solid bed remains at the lower end of the first and / or second storage container.

The first and / or second passage opening on the underside advantageously results in a favorable flow of the fluidizing gas from the first storage tank via the fluidized bed channel to the second storage tank. In order to further improve the flow of the fluidizing gas, the cross section of the first and / or second passage opening is preferably circular. The first and / or the second passage opening is preferably arranged horizontally when the fluidized bed system is in use.

According to a preferred embodiment, the first storage container has a first cylinder section above the first funnel section and / or the second storage container has a second cylinder section above the second funnel section. The cross section of the first and / or the second funnel section is advantageously circular, as a result of which an upper edge of the first funnel section adjoins a lower edge of the first cylinder section and / or an upper edge of the second funnel section adjoins a lower edge of the second cylinder section. According to a particularly preferred embodiment, the central axis of the first cylinder section is congruent with the central axis of the first funnel section and the central axis of the first circular passage opening, as a result of which the first cylinder section, the first funnel section and the first passage opening are arranged axially symmetrically. The central axis of the second cylinder section can be congruent with the central axis of the second funnel section and the central axis of the second circular passage opening. This results in a / 45 rotationally symmetrical shape of the first and / or the second storage container, which is simple to manufacture and has a high ratio of volume to surface of the first and / or second

Storage tank enables.

According to a further preferred embodiment, a first compensating pipe is accommodated in the interior of the first storage container, the first compensating pipe being open at the bottom, preferably also at the top. Alternatively or additionally, a second compensation tube is accommodated in the interior of the second storage container, the second compensation tube being open at the bottom, preferably also at the top. The fluidization device, in particular in the form of the nozzle base, is advantageously designed to bring the solid bed in the first storage container in the inner region enclosed by the first compensating tube into a more fluidized state than in the outer region outside the first compensating tube. Analogously, the fluidization device, in particular in the form of the nozzle base, is preferably designed to bring the solid bed in the second storage container in the inner region enclosed by the second compensating tube into a more fluidized state than in the outer region outside the second compensating tube. As a result, the first or second storage container can be emptied efficiently and mass flow fluctuations of the fluidized bulk material can be greatly reduced.

The first and / or the second compensation tube is preferably arranged substantially vertically, the first and / or the second compensation tube preferably having a circular cross section. In particular, the central axes of the first compensating tube, the first cylinder section and the first passage opening are congruent. Accordingly, the center axes of the second compensating tube, the second cylinder section and the second passage opening can be congruent.

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In this embodiment, the bulk material is advantageously fluidized in the interior of the first or second compensating tube in a favorable manner. The first or second compensating tube preferably has a smaller diameter than the first or second cylinder section. The ratio between the inner diameters of the first or second compensating tube and the first or second cylinder section is preferably between 1: 5 and 1: 500, in particular between 1:20 and 1: 200. According to a particularly preferred embodiment, the first compensating tube extends downwards from the first cylinder section into the first funnel section and / or the second compensating pipe downwards from the second cylinder section into the second funnel section. As a result, the bulk material in the inner region of the first or second compensating tube can be fluidized with the aid of the nozzle base and transported from the first or second storage container into the fluidized-bed channel without large quantities of uncontrolled bulk material from the outer region of the first or second compensating tube in the first or second second funnel area and further into the first or second passage opening. The first or second compensation tube preferably extends over at least 25% of the height of the first or second cylinder section, preferably essentially over the entire height of the first or second cylinder section, in order to ensure controlled fluidization of the bulk material in the first or second storage container To enable bulk material in the first area of the first or second compensating tube.

According to a preferred embodiment, the first compensating tube on the jacket has at least one first compensating opening for the passage of the solid from the outer region outside the first compensating tube into the inner region within the first compensating tube. As an alternative or in addition, the second compensating tube on the jacket preferably has at least one second compensating opening for the passage of the solid from the outer region outside the second compensating tube into the inner region / 45 inside the second compensating tube. Advantageously, bulk material can slide in a controlled manner from the outer region into the inner region of the first or second compensating pipe via the first or second compensating opening in order to be fluidized and discharged from the first or second storage container. Conversely, when the first or second storage container is filled with fluidized bulk material, the bulk material can pass from the inner region of the first or second compensating pipe through the first or second compensating opening into the second region of the first or second compensating pipe.

According to a preferred embodiment, the first compensation opening of the first compensation tube in the first storage container and the second compensation opening of the second compensation tube in the second storage container face each other.

According to a particularly preferred embodiment, a slot, preferably a vertical slot, is provided as the first and / or second compensation opening.

According to a particularly preferred embodiment, the first compensation opening extends over more than half the length, preferably over substantially the entire length, of the first compensation tube. Alternatively or additionally, the second compensation opening extends over more than half the length, preferably over substantially the entire length, of the second compensation tube.

According to an alternative embodiment, a plurality of first compensation openings spaced apart in the vertical direction, preferably slots, in particular horizontal slots, and / or a plurality of second compensation openings spaced apart in the vertical direction, preferably slots, in particular horizontal slots, are provided. One or more horizontal slots preferably extend only over a part of the circumference, preferably over essentially a third of the circumference.

It is expedient if the cross-sectional area of the first passage opening is substantially the same size as the cross-sectional area of the first compensation tube and / or if the cross-sectional area of the second passage opening of the second storage container is substantially the same size as the cross-sectional area of the second compensation tube, for the fluidization in the interior to optimize the first or second compensating tube.

To form a preferably substantially horizontal flow of the solid bed in the fluidized state from the first storage tank via the fluidized bed channel to the second storage tank (or vice versa), it is advantageous if at least one third valve is provided for setting a third pressure in the fluidized bed channel. In the operating state, a third fluidizing gas space is formed in the fluidized bed channel above the solid bed in the fluidized state. With the aid of the third valve, the third pressure of the fluidizing gas in the third fluidizing gas space can be set to a value different from the atmospheric pressure.

As a result, a pressure gradient along the route from the first storage container via the fluidized bed channel to the second storage container can be formed particularly precisely. Of course, a plurality of valves can be provided for setting a plurality of gradually increasing or decreasing pressures along the fluidized bed.

The fluidized bed channel preferably has a third ceiling to which the third valve is connected.

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The flow of the solid bed between the first storage container and the second storage container can be adjusted even more precisely if the fluidized bed channel has at least a first longitudinal section and a second longitudinal section separated by an underflow weir, a fourth valve being provided for setting a fourth pressure in the fluidized bed channel , wherein the first longitudinal section is assigned the third valve and the second longitudinal section the fourth valve. The underflow weir is flowed through by the solid bed in the fluidized state. A resistance plate, in particular a resistance plate, can be provided as an underflow weir. In this embodiment variant, differences in level of the solid bed during transport through the fluidized bed channel can be reduced.

According to a preferred embodiment, a first receiving volume of the first storage container and / or a second receiving volume of the second storage container is a multiple, in particular a multiple, larger than a third receiving volume of the fluidized bed channel, which, viewed in the direction of flow, is located between the first storage container and the second storage container located. Advantageously, the bulk material can therefore be conveyed in the fluidized state from the comparatively large-volume first storage container into the fluidized bed channel and from there to the second storage container.

According to a particularly preferred embodiment, a further fluidized bed channel is connected separately from the fluidized bed channel on one side to the first storage container and on the other side to the second storage container. In this embodiment, the first and the second storage container are connected to one another via two fluidized bed channels, which are preferably completely separated from one another. This embodiment is advantageous, for example, when the fluidized bed channel and the further fluidized bed channel are to be designed for different applications in which the same first and second storage containers are to be used in each case.

In a preferred application of the fluidized bed system, a heat exchanger projecting into the fluidized bed channel and / or a heating element, in particular a heating electrode, is provided. The arrangement of the heat exchanger means that the fluidized bed system described above can be used as a fluidized bed heat exchanger. Furthermore, the heating element can be provided for heating the solid bed, in particular to enable temporary storage of electrical energy. In a further preferred embodiment, the heat exchanger is connected to a Stirling engine, so that the solid bed can be used as a heat source for the Stirling engine.

A Stirling engine has a structure which is well known in the prior art, in which a working medium runs through a closed cycle. In the Stirling engine, the hermetically sealed working medium (usually a gas such as helium) is heated by energy supplied from outside in a closed room (first cylinder) and cooled in another closed room (second cylinder). The energy heat supply for the conversion of internal or thermal energy into mechanical energy (i.e. wave work) works indirectly via a hot gas heat exchanger, which is immersed in the fluidized bed channel in this embodiment variant. In contrast to this, for example in the case of a gasoline or diesel engine, the fuel is introduced directly into the displacement together with the oxygen carrier, the fuel is oxidized and the exhaust gas is removed again. Unlike the internal combustion engines mentioned, the Stirling engine is a heat engine. The indirect heat exchange has the advantage that the heat transfer medium or the heat source does not come into direct contact with mechanically sensitive (movable) components, which greatly reduces the risk of corrosion.

In this embodiment, heat energy stored in the solid bed can be converted via the heat exchanger into mechanical energy of the Stirling engine, which can be connected to a generator. This version is particularly suitable for a “power to heat to power concept, in which heat is first generated using electricity and the stored heat is converted into electricity if required. This creates an advantageous possibility of storing electricity from renewable energies in times of surplus in the bulk solids and feeding it into the power grid if necessary.

In a preferred embodiment, a heating element, in particular a heating electrode, is provided in the fluidized bed channel, with which the solid bed can be heated when it is transported through the fluidized bed channel.

In a further preferred embodiment, a supply device for supplying hot gas into the fluidized bed channel above the nozzle base is provided. The particles of the solid bed can be heated by supplying the hot gas. In this embodiment, the hot gas is designed as a heat source for the heat exchanger of the Stirling engine, the fluidized bed in the fluidized bed channel enabling the heat transfer from the hot gas to the working medium of the heat exchanger. The fluidized bed of solids acts as a dynamic fin to optimize the heat exchange. By supplying the hot gas above the nozzle base, the nozzle base can be spared. In this embodiment, only the clean, possibly preheated fluidizing gas is introduced via the nozzle base in order to bring the solid bed into the fluidized state. In contrast, the hot gas is direct, i.e. bypassing the bottom of the nozzle into the solid bed so that the hot gas may be (slightly) corrosive or

/ 45 (slightly) contaminated.

In order to protect the heat exchanger for the Stirling engine from harmful influences of the hot gas, in a preferred embodiment the heat exchanger is arranged in a first area and the supply device for the hot gas in a second area of the fluidized bed channel, a plate-shaped guide element in particular covering the first area of delimits the second area. It can advantageously be achieved so reliably that the hot gas does not hit the sensitive heat exchanger for the Stirling engine, or only in small proportions. The plate-shaped guide element is arranged in the fluidized bed channel in such a way that a passage opening between the first area with the heat exchanger and the second area with the feed device is opened. By introducing the hot gas, a higher degree of fluidization is provided in the second area than in the first area. As a result, a circulation flow is formed between the second region and the first region. An effective heat transfer from the hot gas via the particles of the fluidized bed to the heat exchanger for the Stirling engine can thus be achieved.

In order to achieve the desired protective effect for the heat exchanger, the guide element is preferably arranged essentially perpendicular to the bottom of the nozzle.

The passage opening between the second area with the supply device for the hot gas and the first area with the heat exchanger for the Stirling engine is preferably formed between a lower edge of the guide element and the nozzle bottom and / or above an upper edge of the guide element.

According to a preferred embodiment, the solid bed consists of microencapsulated latent storage particles.

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In the method according to the invention for conveying a solid bed from a first storage container via a fluidized bed channel to a second storage container, at least the following steps are carried out:

Arranging the solid bed in the first storage container, in the fluidized bed channel and in the second storage container,

Fluidizing the solid bed in the fluidized bed channel,

Fluidizing at least part of the solid bed of the first storage container,

Fluidizing at least part of the solid bed of the second storage container,

- Forming a pressure difference between the first storage container and the second storage container, so that the solid bed in the fluidized state is conveyed from the first storage container via the fluidized bed channel to the second storage container.

For the fluidization of the solid bed, a nozzle base is preferably provided, which extends over at least part of the horizontal extent of the first storage tank, the fluidized bed channel and the second storage tank.

For the purposes of this disclosure, the location and direction information, such as "above," below, "vertical," horizontal etc., refer to the operating state of the fluidized bed system.

The invention is explained in more detail below on the basis of preferred exemplary embodiments, to which, however, it should not be restricted. In detail shows:

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Figure 1 is a schematic view of a fluidized bed system according to the invention with a first and a second storage tank for a solid bed and a fluid bed channel arranged between them, the solid bed being conveyed in the fluidized state from the first storage tank via the fluidized bed channel to the second storage tank;

FIG. 2 shows the fluidized bed system according to FIG. 1 in plan view;

3 shows a further fluidized bed installation according to the invention in plan view;

4 shows a variant of the first storage container with a first compensating tube which has a plurality of transverse slots;

5 shows a further embodiment variant of the first storage container, in which the first compensating tube has a longitudinal slot which extends essentially over the entire length;

6a to 6d schematically a time course of a bulk material distribution in the fluidized bed system according to FIG. 1;

7 shows a further embodiment of the fluidized bed system;

FIG. 8 the fluidized bed system according to FIG. 7 in a top view;

9 shows the fluidized bed system according to FIGS. 7 and 8 in cross section;

10 shows a further embodiment of the fluidized bed system; and

11 shows a further embodiment of the fluidized bed system.

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1 shows a fluidized bed system 1 with a first storage container 2 and a second storage container 3, in each of which particulate solids of a solid bed 4 are accommodated. Sand particles, for example, can be provided as solids. The second storage container 3 is connected to the first storage container 2 via a fluidized bed channel 5. Solids of the solid bed 4 are likewise arranged in the fluidized bed channel 5. The fluidized bed system 1 has on the underside a fluidization device with a nozzle base 6 for introducing a fluidization gas. The nozzle base 6 extends in a horizontal direction from below the first storage tank 2 over the length of the fluidized bed channel 5 to the second storage tank 3.

The nozzle base 6 can be designed in a conventional manner. Accordingly, as described in AT 515 810 A1, the nozzle base can have a wind box and a double-bottomed nozzle base arranged above it, which comprises a base plate provided with a plurality of nozzles and an overlying distributor plate which define a gas space therebetween. The double-bottomed nozzle plate can be a continuous nozzle plate with a porous or perforated distributor plate. The gas space of the nozzle base can be divided into a plurality of compartments by means of a plurality of walls between the base plate and the distributor plate.

The first storage container 2 has a horizontal, circular first passage opening 43. Correspondingly, the second storage container 3 has a horizontal, circular second passage opening 44. The first storage container 2 has a first funnel section 45, which is arranged at a lower end of the first storage container 2 above the first passage opening 43. The second storage container 3 has a second funnel section 46 which is arranged at a lower end of the second storage container 3 above the second passage opening 44. Above the first 45 or second 46 funnel section, the first 2 or second 3 storage containers have a first 47 or second 48 cylinder section, the first 45 or second 46 funnel section adjoining a lower edge of the first 47 or second 48 cylinder section. A first compensating tube 41 is received in the interior of the first storage container 2, the first compensating tube 41 being open at the bottom and at the top. In addition, a second compensating tube 49 is accommodated in the interior of the second storage container 3, the second compensating tube 49 being open at the bottom and at the top. The first compensation tube 41 has at least one compensation opening 42 on the jacket. In the embodiment variant according to FIG. 1, a plurality of first compensating openings 42 spaced apart in the vertical direction are provided, which are formed as horizontal slots in the embodiment according to FIG. 1. Analogously, the second compensating tube 49 on the jacket has a plurality of second compensating openings 50 which are spaced apart in the vertical direction and which, in the embodiment according to FIG. 1, are designed as horizontal slots which extend over substantially one third of the circumference of the second compensating tube 49. The ratio between the diameters of the first 41 or second 49 compensating tube and the first 47 or second 48 cylinder section is essentially 1: 5 in the embodiment shown. The first 41 or second 49 compensating tube extends downward from the first 47 or second 48 cylinder section into the first 45 or second 46 funnel section and over the entire height of the first 47 or second 48 cylinder section in order to accommodate large bulk material heights in the first second or second 3 storage containers to enable controlled fluidization of the bulk material in the interior of the first 41 or second 49 compensating tube. The central axes of the first cylinder section 47, the first funnel section 45, the first compensating tube 41 and the central axis of the first circular passage opening 43 are congruent, as a result of which the first cylinder section 47, the first funnel section 45, / 45 the first compensating pipe 41 and the first passage opening 43 are axially symmetrical are arranged. Analogously, the central axes of the second cylinder section 48, the second funnel section 46, the second compensating tube 49 and the central axis of the second circular passage opening 44 are congruent.

The first storage container 2 has a first cover 7, the second storage container 3 has a second cover 8 and the fluidized bed channel 5 has a third cover 9. A first valve 10 for setting a first gas pressure p1 in a first fluidizing gas space 2a in the first storage container 2 is provided on the first ceiling 7 of the first storage container 2. A second valve 11 for setting a second gas pressure p2 in a second fluidizing gas space 3a in the second storage container 3 is provided on the second ceiling 8 of the second storage container 3. In the embodiment shown, the fluidized bed channel 5 has a first longitudinal section 12 and a second longitudinal section 13, which are separated from one another by an underflow weir 14. On the third ceiling 9 there is a third valve 15 for setting a third gas pressure p3 in a third fluidizing gas space 12a in the first longitudinal section 12 of the fluidized bed channel 5 and a fourth valve 16 for setting a fourth gas pressure p4 in a fourth fluidizing gas space 13a in the second longitudinal section 13 of the fluidized bed channel 5 is provided. The first valve 10, the second valve 11, the third valve 15 and the fourth valve 16 can be designed as conventional pressure control valves. The nozzle base 6 is connected to a fluidizing gas supply 17, which is shown only symbolically in FIG. 1. The fluidizing gas is introduced by means of the fluidizing gas supply 17 via the nozzle base 6 into the first storage tank 2, into the fluidized bed channel 5 and into the second storage tank 3 and leaves the first storage tank 2 via the first valve 10, the second storage tank 3 via the second valve 11, the first longitudinal section 12 of the fluidized bed channel 5 via the third valve 15/45 and the second longitudinal section 13 of the fluidized bed channel 5 via the fourth valve 16. In FIG. 1, a derivation is shown schematically, via which the fluidizing gas is discharged.

By setting a pressure gradient between the first storage container 2 and the second storage container 3, the solid bed 4 is conveyed in the fluidized state from the first storage container 2 along the fluidized-bed channel 5 in a horizontal direction (see arrow 19) to the second storage container 3. The first pressure p1 in the first storage container 2 is higher than the third pressure p3 in the first longitudinal section 12 of the fluidized bed channel 5, which is higher than the fourth pressure p4 in the second longitudinal section 12 of the fluidized bed channel 5, which in turn is higher than the second pressure p2 is in the second storage container 3. Of course, such a pressure gradient can also be built up in the opposite direction (i.e. with p1 <p3 <p4 <p2) in order to reverse the transport direction.

Inside the first compensating pipe 41 there is an inner region 51 in which bulk material is fluidized with the aid of a first 6a nozzle bottom section of the nozzle bottom 6. The bulk material, which is located outside the first compensation tube 41 in an outer region 52, is less fluidized due to the delimitation with the aid of the first compensation tube 41. If fluidized bulk material is transported away from the inner region 51, bulk material migrates from the outer region 52 via the first equalization openings 42 into the inner region 51 of the first equalization tube 41 in order to be more fluidized there and to be transported away from the first storage container 2. Inside the second compensating tube 49 there is an inner region 53 in which bulk material is fluidized with the aid of a third 6c nozzle base section of the nozzle base 6. The bulk material, which is located outside of the second compensation tube 49 in an outer area 54/45, is less fluidized due to the delimitation with the aid of the second compensation tube 49. If fluidized bulk material is transported away from the inner region 53, bulk material migrates from the outer region 54 via the first equalization openings 50 into the inner region 53 of the second equalization tube 49 in order to be more fluidized there and transported away from the second storage container 3. Conversely, when the first storage container 2 is filled with bulk material, the bulk material is transported via the first passage opening 43 into the inner region 51 of the first compensating pipe 41 in the fluidized state and passes through the first compensating openings 42 into the outer region 52 of the first compensating pipe 41 second storage container 3, the bulk material is transported via the second passage opening 44 into the inner region 53 of the second compensating tube 49 in the fluidized state and passes through the second compensating openings 50 into the outer region 54 of the second compensating tube 49.

No mechanical or pneumatic particle conveyors are provided between the first storage tank 2 and the fluidized bed channel 5 or between the fluidized bed channel 5 and the second storage tank 3. In the arrangement shown, air injections 6g, 6h are also provided adjacent to the first 43 or second 44 passage opening to improve the flow behavior in the first storage container 2 or in the second storage container 3. The fluidized bed channel 5 is delimited on one side by a first partition wall 26, the solid material being able to flow into the fluidized bed channel below the first partition wall 26. On the other hand, the fluidized bed channel is delimited by a second partition wall 28, the solid material being able to flow into the fluidized bed channel below the second partition wall 28.

As can be seen from FIGS. 1, 2, a first receiving volume of the first storage container 2 and a second receiving volume of the second storage container 3 are each a multiple, in particular a multiple, larger than a third receiving volume of the fluidized bed channel 5 between the first storage container 2 and the second storage container 3. In the embodiment shown, the interior of the fluidized bed channel 5 has both a smaller height (cf. FIG. 1) and a smaller width (cf. FIG. 2) than the first storage container 2 and as the second storage container 3 on. The first storage container 2 and the second storage container 3 are preferably of identical design.

The fluidized bed system 1 has a (schematically illustrated) heat exchanger 32 which is immersed in the solid bed 4 in the fluidized bed channel 5.

In the embodiment of FIG. 3, a further fluidized bed channel 31 is provided between the first storage container 2 and the second storage container 3. In the embodiment shown, the fluidized bed channel 5 and the further fluidized bed channel 31 are separated from one another in the region between the first storage container 2 and the second storage container 3.

FIG. 4 shows the first storage container 2 of the fluidized bed system 1 in the embodiment according to FIG. 1, in which the first compensating tube 41 is arranged axially symmetrically with respect to the first passage opening 43. The first compensating pipe 41 is open at the bottom and at the top and has five first compensating openings 42 at a distance from one another in the vertical direction, which are formed as horizontal slots in the embodiment according to FIG. 4. The horizontal slots extend less than a quarter of the circumference of the first compensating tube 41. The second storage container 3 can be designed accordingly.

5 shows the first storage container 2 in a further embodiment. In this particularly preferred embodiment, the compensating tube 41 has a single first / 45 on the jacket

Compensation opening 42, which is designed as a vertical slot, which extends essentially over the entire height of the compensation tube 41.

6a to 6d show a time profile of a bulk material distribution in the fluidized bed system 1 according to FIG. 1. As the storage status of the bulk material shown in FIG. 6a in the first 2 and in the second 3 storage container shows, the first storage container 2 is almost entirely with bulk material the solid bed 4 filled, whereas the second storage container 3 is largely empty. If the bulk material is fluidized in the fluidized bed channel 5 and in parts of the first 2 and the second 3 bulk goods container and a higher pressure is generated in the first storage tank 2 than in the fluidized bed channel 5 and in the second storage tank 3, fluidized bulk material is predominantly through the inner region 51 of the first compensating tube 41 transported away from the first storage container 2 and initially reaches the inner region 53 of the second compensating tube 49 of the second storage container 3 via the fluidized-bed channel 5. As shown in FIG. 6b, bulk material begins in the outer region 52 outside the first compensating tube 41 in the region of the first compensating openings 42 ( cf. FIG. 1) to slide into the inner region 51 in order to be more fluidized and to be discharged from the first storage container 2. In the second storage container 3, fluidized bulk material reaches in the area of the second equalization openings 50 (cf. FIG. 1) from the inner area 53 in the interior of the second equalization tube 49 to the outer area 54 outside the second equalization tube 49. As shown in FIG. 6c, it migrates due to an increasing Height difference of the bulk material between the inner region 51 and the outer region 52 inside and outside the first compensating tube 41 bulk material from the outer region 52 into the inner region 51, in which the bulk material is fluidized and discharged from the first storage container 2. Conversely, the higher level of bulk material in the inner region 53 in the interior of the second compensating tube 49 compared to the outer 23/45 region 54 outside the second compensating tube 49 leads to the bulk material migrating from the inner region 53 into the outer region 54 of the second compensating tube 49. As a result, as shown in Fig.

6d, the first storage container 2 is emptied and the second storage container 3 is filled with bulk material.

In the embodiment of FIGS. 7 to 9, the heat exchanger 32 is connected to a Stirling engine 33 (shown schematically). In the embodiment shown, two heat exchangers 32 are provided, each of which is connected to a Stirling engine 33. In addition, a supply device 34 for supplying hot gas into the fluidized bed channel 5 is provided above the nozzle base 6. The heat exchangers 32 are arranged in two first regions of the fluidized bed channel 5, which, viewed in the direction of flow 19, each extend laterally to a second region of the fluidized bed channel 5, in which the feed device 34 for the hot gas is arranged. The first regions 35 are each delimited from the second region 36 by a plate-shaped guide element 37. In the embodiment shown, the guide elements 37 are arranged essentially perpendicular to the nozzle base 6 (or to the flow direction 19). Due to the introduction of the hot gas via the feed device 34, the particles are more fluidized in the second region 36, so that a circulation flow (see arrows 38) forms on the top and bottom sides around the plate-shaped guide elements 37. As a result, the particles pass from the second region 36 into the first regions 35 in order to give off heat to the heat exchangers 32 for the Stirling engines 33 there. By means of heating elements 39, which are preferably designed as heating electrodes, the particle flow directed according to arrow 40 from container 3 into container 2 can be heated and thus the heat accumulator can be charged.

The embodiment of FIG. 10 corresponds essentially to that of FIG. 1, but the first 2 and the second 3 storage containers / 45 are essentially rectangular in longitudinal section. The fluidized bed channel 5 merges directly into the first storage container 2 on one side and directly into the second storage container 3 on the other side. In the embodiment shown in FIG. 10, the nozzle base 6 extends over the entire length of the first storage container 2, the fluidized bed channel 5 and the second storage container 3. In a first operating state, the nozzle base 6 is designed to accommodate the solid bed 4 in the first storage container 2 to be brought into the fluidized state in a first region 20 facing the fluidized bed channel 5, but to be kept in the non-fluidized state in a second region 21 facing away from the fluidized bed channel 5. Accordingly, the solid bed 4 in the second storage container 3 is brought into the fluidized state in a first region 22 facing the fluidized bed channel 5, but is kept in the non-fluidized state in a second region 23 facing away from the fluidized bed channel 5. In contrast, the nozzle base 6 can be controlled in a second operating state such that essentially the entire solid bed 4 in the first storage container 2 (or correspondingly in the second storage container 3) is brought into the fluidized state (not shown).

In order to enable switching between the first and the second operating mode, the nozzle base 6 in the embodiment shown in FIG. 10 has the first nozzle base section 6a below the first area 20 of the first storage container 2 and the second nozzle floor section 6b below the second area 21 of the first Storage container 2 on. The fluidizing gas supply 17 has a controllable shut-off valve 24 for switching the second nozzle base section 6b on or off. In addition, the nozzle base 6 has the third nozzle base section 6c below the first region 22 of the second storage container 3/4 and the fourth nozzle base section 6d below the second region 23 of the second storage container 3. In order to be able to supply the fourth nozzle base section 6d with fluidizing air as required, the fluidizing gas supply 17 has a further controllable shut-off valve 25 for switching the fourth nozzle base section 6d on or off. Finally, the nozzle floor 6 has a fifth nozzle floor section 6e below the first longitudinal section 12 of the fluidized bed channel 5 and a sixth nozzle floor section 6f below the second longitudinal section 13 of the fluidized bed channel 5.

The embodiment of FIG. 11 essentially corresponds to that of FIG. 10, but the nozzle base 6 does not have the nozzle base sections 6b, 6d below the second regions 21, 23. Accordingly, in this embodiment, only the first regions 20, 22 of the first 2 or second 3 storage container can be fluidized. In this embodiment, the second regions 21, 23 of the first 2 and second 3 storage containers drop from the outside to the fluidized bed channel 5, the first regions 20, 22 of the first 2 and second 3 storage containers falling down relative to the second regions 21, 23 protrude.

The following method for conveying a solid bed 4 from a first storage tank 2 via a fluidized bed channel 5 to a second storage tank 3 can be carried out with the fluidized bed system 1:

Arranging the solid bed 4 in the first storage container 2, in the fluidized bed channel 5 and in the second storage container 3,

Fluidizing the solid bed 4 in the fluidized bed channel 5,

Fluidizing at least part of the solid bed 4/45 of the first storage container 2,

Fluidizing at least part of the solid bed 4 of the second storage container 3,

- Forming a pressure difference between the first storage container 2 and the second storage container 3, so that the solid bed 4 is conveyed in the fluidized state from the first storage container 2 via the fluidized bed channel 5 to the second storage container 3.

Claims (19)

1. Fluidized bed system (1) comprising: - a fluidized bed channel (5), - a first storage container (2) for a solid bed (4), - A second storage container (3) for the solid bed (4), the second storage container (3) being connected to the first storage container (2) via the fluidized bed channel (5), characterized by - A fluidizing device, in particular a nozzle bottom (6) extending from the first storage tank (2) via the fluidized bed channel (5) to the second storage tank (3), for introducing a fluidizing gas into the fluidized bed channel (5), into the first storage tank (2) and in the second storage container (3), - a first valve (10) for setting a first pressure (p1) of the fluidizing gas in the first storage container (2), - a second valve (11) for setting a second pressure (p2) of the fluidizing gas in the second storage container (3), so that by setting a pressure difference between the first pressure (p1) in the first storage container (2) and the second pressure ( p2) in the second storage container (3) the solid bed (4) can be conveyed in the fluidized state from the first storage container (2) via the fluidized bed channel (5) to the second storage container (3). 28/45 2. Fluidized bed system (1) according to claim 1, characterized in that the first storage container (2) has a first funnel section (45) which has a first passage opening (43) on the underside of the first funnel section (45) with the fluidized bed channel (5 ) and / or that the second storage container (3) has a second funnel section (46) which is connected to the fluidized bed channel (5) via a second passage opening (44) on the underside of the second funnel section (46). 3. Fluidized bed system (1) according to claim 1 or 2, characterized in that a first compensating tube (41) is accommodated in the interior of the first storage container (2), the first compensating tube (41) being open at the bottom, preferably also at the top and / or that a second compensation tube (49) is accommodated in the interior of the second storage container (3), the second compensation tube (49) being open at the bottom, preferably also at the top. 4. Fluidized bed system (1) according to claim 3, characterized in that the first compensation tube (41) on the jacket at least a first compensation opening (42) for the passage of the solid from an outer region (52) outside the first compensating tube (41) into an inner region ( 51) inside the first compensating pipe (41) and / or that the second compensating pipe (49) on the jacket has at least one second compensating opening (50) for the passage of the solid matter from an outer region (54) outside the second compensating pipe (49) into an inner region (53 ) within the second compensating tube (49). 5. Fluid bed system (1) according to claim 4, characterized in that a slot, preferably a vertical slot, is provided as the first (42) and / or second (50) compensating opening. 29/45 6. Fluidized bed system (1) according to claim 4 or 5, characterized in that the first compensation opening (42) over more than half the length, preferably over substantially the entire length, of the first compensation tube (41) and / or that second compensation opening (50) extends over more than half the length, preferably over substantially the entire length, of the second compensation tube (49). 7. Fluidized bed system (1) according to claim 4 or 5, characterized in that a plurality of first equalization openings spaced apart in the vertical direction, preferably slots, in particular horizontal slots, are provided and / or that a plurality of second equalization openings spaced apart in the vertical direction are preferably provided Slots, especially horizontal slots, are provided. 8. fluidized bed system (1) according to one of claims 3 to 7 with claim 2, characterized in that the cross-sectional area of the first passage opening (43) of the first storage container (2) is substantially the same size as the cross-sectional area of the first compensating tube (41) and / or that the cross-sectional area of the second passage opening (44) of the second storage container (3) is essentially the same size as the cross-sectional area of the second compensating tube (49). 9. Fluidized bed system (1) according to one of claims 1 to 8, characterized by a third valve (15) for setting a third pressure (p3) of the fluidizing gas in the fluidized bed channel (5). 10. Fluidized bed system (1) according to claim 9, characterized in that the fluidized bed channel (5) has at least a first longitudinal section (12) and a second longitudinal section (13) separated therefrom by an underflow weir (14), a fourth valve (16) for setting a fourth pressure (p4) in the 30/45 Fluidized bed channel (5) is provided, the third valve (15) being assigned to the first longitudinal section (12) and the fourth valve (16) being assigned to the second longitudinal section (13). 11. Fluidized bed system (1) according to one of claims 1 to 10, characterized in that a first receiving volume of the first storage container (2) and / or a second receiving volume of the second storage container (3) is a multiple, in particular a multiple, greater than is a third receiving volume of the fluidized bed channel (5). 12. Fluidized bed system (1) according to one of claims 1 to 11, characterized by a further fluidized bed channel (31) which is separate from the fluidized bed channel (5) on one side with the first storage container (2) and on the other side with the second Storage container (3) is connected. 13. Fluidized bed system (1) according to one of claims 1 to 12, characterized by a in the fluidized bed channel (5) projecting heat exchanger (32) and / or a heating element (39), in particular a heating electrode. 14. Fluidized bed system (1) according to claim 13, characterized in that the heat exchanger (32) is connected to a Stirling engine (33). 15. Fluidized bed system (1) according to one of claims 1 to 14, characterized in that a supply device (34) for supplying hot gas into the fluidized bed channel (5) is provided above the nozzle base (6). 16. Fluidized bed system (1) according to claim 14 or 15, characterized in that the heat exchanger (32) in a first area (35) and the feed device (34) for the hot gas in a second area (36) of the fluidized bed channel (5) 31/45, a plate-shaped guide element (37) delimiting the first region (35) from the second region (36). 17. Fluidized bed system (1) according to claim 16, characterized in that the guide element (37) is arranged substantially perpendicular to the nozzle base (6). 18. Fluidized bed system (1) according to one of claims 1 to 17, characterized in that the solid bed (4) consists of microencapsulated latent storage particles. 19. A method for conveying a solid bed (4) from a first storage container (2) via a fluidized bed channel (5) to a second storage container (3), comprising the steps: Arranging the solid bed (4) in the first storage container (2), in the fluidized bed channel (5) and in the second storage container (3), - Fluidizing the solid bed (4) in the fluidized bed channel (5), - Fluidizing at least part of the solid bed (4) of the first storage container (2), - fluidizing at least part of the solid bed (4) of the second storage container (3), - Forming a pressure difference between the first storage container (2) and the second storage container (3), so that the solid bed (4) in the fluidized state is conveyed from the first storage container (2) via the fluidized bed channel (5) to the second storage container (3) becomes.