DE20307558U1 - Fluidized bed process unit, useful the treatment of powdered or granular chemicals, pharmaceuticals or food ingredients, comprises an annular working chamber - Google Patents

Abstract

A fluidized bed unit, particularly for continuous flow processing, has a rotational-symmetric working chamber (10) with an internal, central hub (4), defining an annular working space. Preferably the hub (4) is conical or cylindrical (claimed). The working space may be divided into sequential process stages by radial partitions (15) connected by flap-closed weirs (16), so that with separate air supplies to the sieve floors, different conditions can be controlled in each stage (claimed).

Description

16352/si/sc
Utility model application

Heinen Drying Technology GmbH, Achternstraße 1- 17, 26316 Varel

Fluidized bed apparatus

The invention relates to a fluidized bed apparatus, in particular a continuously operating fluidized bed apparatus for treating powdery or granular products of the pharmaceutical, chemical and/or food industry, with a product container and with a sieve bottom provided in the product container, which is supplied with air from below.

A fluidized bed apparatus of the type mentioned above is known from DE 197 00 029 A1. This publication discloses a fluidized bed apparatus in which several areas or stages are created by using weirs one after the other, in which the speed and the amount of the fluidization medium supplied can be adjusted.

The invention is based on the object of creating a fluidized bed apparatus in which particularly favorable

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several steps can be carried out in this way and which is explosion-proof and, in particular, pressure shock-resistant.

This object is achieved with a fluidized bed apparatus having the features of claim 1. Advantageous developments of the invention are described in the subclaims.

In a fluidized bed apparatus, in particular a continuously operating fluidized bed apparatus for treating powdered or granular products of the pharmaceutical and/or food industry, with a product container and with a sieve bottom provided in the product container, which is supplied with air from below, it is essential to the invention that the product container is rotationally symmetrical, that the product container has at least one inlet and at least one outlet and that a centrally inserted body is provided which, together with the rotationally symmetrical product container, defines an annular product flow. With such a fluidized bed apparatus, pressures or pressure surges of up to 12 bar can be absorbed due to the rotationally symmetrical arrangement. Such pressures can occur due to dust or gas mixture explosions. In particular with active substances that develop a high level of effectiveness in low concentrations, such as pharmaceutical active substances, discharging the explosion into the environment is not permitted. Devices that detect an incipient explosion and

Extinguishing agents suppress the extinguishing agents, but at the same time lead to the detrimental contamination of the apparatus with extinguishing agents. The rotationally symmetrical design of the product container makes it possible to absorb pressures of up to 12 bar. In addition to the pressures that can occur due to explosions, this concept also makes it possible to run processes at higher pressures in general. This is particularly interesting for (water) steam in combination with temperatures above 100° C. The product container has an inlet and an outlet. The centrally placed body, which together with the rotationally symmetrical product container defines the product plane as a ring surface, so that a ring-shaped product flow is created, which can be circular or based on an elliptical ring, in combination with the inlet and the outlet, almost a "first in - first out" principle is provided. In this way, continuous operation can be achieved particularly well.

In a preferred development of the invention, the fluidized bed apparatus is designed to be rotationally symmetrical overall. The fluidized bed apparatus can have inlets and outlets that are not rotationally symmetrical. The design of the housing and in particular the design of the inner wall are crucial for the rotationally symmetrical design of the fluidized bed apparatus. Elliptical designs of the fluidized bed apparatus, i.e.

Slight deviations from the strictly mathematically considered rotationally symmetrical body are to be understood as rotationally symmetrical in the sense of the formation of a pressure-resistant fluidized bed apparatus described here.

The centrally placed body preferably has the shape of a cone or a cylinder, so that together with the rotationally symmetrical product container the product plane is defined as a circular path or as a ring surface. With such a design of the fluidized bed apparatus, a continuously operating process can be particularly well developed within the rotationally symmetrical apparatus. The centrally placed body is in particular rotationally symmetrical, in particular mirror-imaged to the outer wall of the container. The circumference of the centrally arranged body can be constant or can change continuously, for example it can have a conical shape.

The product container is preferably divided into several segments between the inlet and outlet. In this way, the ring-shaped product flow can be processed in a targeted manner in different stages. Preferably, each segment is assigned its own air supply nozzle in order to be able to control and adjust the conditions within each segment particularly well.

In a preferred further development of the invention, two or more inlet openings are provided in the product container, in particular in the product plane, i.e. in the area above the sieve bottom.

areas and two or more outlet areas are provided. In this case, one inlet area and one outlet area are preferably arranged next to one another, with the inlet areas and outlet areas arranged next to one another being assigned to the various product sections. The product section or product stream does not, however, run through the complete 360° circular path, but is instead led to the first outlet after 180°, for example. For the remaining 180°, a product is again fed in through a lock or an inlet. The number of subdivisions that make sense in terms of process technology depends on the size of the overall apparatus geometry. In this way, two or more different product sections can be formed in parallel within a suitably large fluidized bed apparatus. This is particularly advantageous for simple processes with only one or two different process steps, since it is possible to operate two or more product sections in parallel in the fluidized bed apparatus. It is also possible to discharge the product after passing through the first product section, to treat it outside the fluidized bed apparatus and then to reinsert it into the second product section of 180° or a correspondingly different division and to subject it to further treatment, for example a drying process.

Preferably, each supply air nozzle has its own control for setting the air temperature and other parameters. Each nozzle is preferably provided with its own technical

unit that generates the necessary conditions. In addition to the air temperature, the air humidity, the air volume and the air purity must be adjusted. Gases and vapors can also be processed and supplied as an option.

In another preferred development of the invention, the fluidized bed apparatus has a housing base, a sieve bottom, a product container and a filter housing as separate components, whereby these components are designed to be detachable from one another. Inflatable seals are advantageously provided for the detachable connection of the components of the fluidized bed apparatus. The connections are preferably designed as couplings which have a mechanical stop in the vertical direction. In order to fit the housing parts together, a certain gap is necessary. Inflatable seals are used to seal this gap. In another preferred embodiment, the housing parts can be sealed by applying a vertical force over the entire fluidized bed apparatus. Seals are located at the separation points, whereby the vertical force applied must be large enough to withstand the pressures occurring in the apparatus. In another embodiment of the invention, the filter housing arranged in the fluidized bed apparatus in the preferred embodiment can also be designed as a dust separator downstream of the fluidized bed apparatus.

Partition walls are preferably provided in the product level, which divide the product level into several segments. Furthermore, wall elements are preferably provided in the lower part of the housing, which divide the lower part of the housing into different segments, whereby these segments correspond to the segments in the product container. Furthermore, spray nozzles are preferably provided above the product level, with which the product level can also be supplied with liquid substances. The partition walls do not extend all the way down to the sieve bottom. In the last area above the sieve bottom, weirs are provided adjoining the partition walls, which allow the product to pass through to a certain extent and/or after a certain time and/or after certain parameters have been reached. In a preferred embodiment, the weir is arranged so that it can pivot on the partition wall, with the pivot point being positioned above the expected product layer. The weir is bent or angled in one direction in the lower end area, whereby the direction of the bend corresponds to the direction of the product flow. The pivoting movement of the weir also takes place in the direction of the product flow. In another preferred embodiment, the weir can be pivoted or rotated around a central point, whereby in this case bends are provided at both end areas. A rotational movement is thus only possible in such a way that the weir can only be pivoted in one direction in the area below the pivot point. The previously described

The pivoting weir can only be pivoted up in one direction. In a further preferred embodiment, the weir is made up of two weirs or partial weirs arranged one above the other, each of which can be rotated about its center point. These weirs correspond in their design to the previously described single pivoting weir, with bends being provided in each end area, which mean that the weir rests on the sieve bottom with the angled end, can be rotated to a horizontal position so that passage is then possible, and then pivots down again. Pivoting against the intended direction is prevented by the angled end area striking the sieve bottom and making it impossible to rotate in the direction opposite to the product flow. The pivoting movement can take place either against the direction of the product flow or, in other configurations, in the direction of the product flow. It is preferred that the partitions are designed in such a way that pivoting through is reliably prevented. Furthermore, the partitions are preferably designed in such a way that the partitions are prevented from wedging on the sieve bottom. This is preferably achieved by a bend in the lower end area. In another preferred embodiment, the weir is designed as a height-adjustable extension of the partition wall, whereby the weir in this case has a

system has an angle that is designed in the direction of the product flow.

The invention is explained in more detail below with reference to a preferred embodiment shown in the drawing. The schematic representations show

Fig. 1: a schematic overall view of an inventive
fluidized bed apparatus;

Fig. 2: a sectional view of the fluidized bed apparatus along the line II-II according to Fig. 1;

Fig. 3: a sectional view of the fluidized bed apparatus along line III-III according to Fig. 1;

Fig. 4: another schematic external view of a
fluidized bed apparatus;

Fig. 5: a sectional view along the line
VV according to Fig. 4;

Fig. 6: a sectional view of the fluidized bed apparatus along line VI-VI according to Fig. 4;

Fig. 7: another sectional view of the fluidized bed apparatus
along line VII-VII according to
Fig.4;

Fig. 8: a first alternative embodiment to Fig. 5
of the fluidized bed apparatus in
a sectional view along line VV in
Fig.4;

Fig. 9: a second alternative embodiment to Fig. 5
of the fluidized bed apparatus in
a sectional view along line VV in
Fig. 4 and

Fig. 10: a third alternative embodiment to Fig. 5
of the fluidized bed apparatus in
a sectional view along line VV in
Fig.4.

Fig. 1 shows a schematic view of the rotationally symmetrical fluidized bed apparatus according to the invention.

The fluidized bed apparatus has a housing base 1, a product container 10 and a filter housing 20. A series of air inlet nozzles 2, 3 are provided in the housing base 1, of which the two air inlet nozzles 2, 3 are shown or can be seen here. Furthermore, a molded part 4 is provided up to the lower area of the housing base 1, which is conical and in this way defines a ring shape in the product area. The molded part 4 is a centrally arranged body. The product container 10 is provided above the housing base 1, which has a sieve bottom 11 at its lower end, i.e. in the transition area to the housing base 1. The product level 12 is provided on the sieve bottom 11. The molded part 4, which extends into the product container 10, forms the sieve bottom 11.

ring-shaped. The space formed in the product container 10 is also referred to as the vortex space 17. In the upper area of this vortex space 17, spray nozzles 13 are provided in the vortex space 17. Above the product container 10, the filter housing 20 is provided, in which filters 21 are provided, through which air supplied via the supply air nozzles 2 is extracted and led out via the exhaust air nozzles 24. Above the filters 21, a container cover 22 is provided and above this a head cover 23, in which the exhaust air is led in pipes to the exhaust air nozzles 24.

Fig. 2 shows a section along the line II-II in Fig. 1. A total of six individual filters 21 are provided within the rotationally symmetrical, cylindrical filter housing 20. The filters 21 are each surrounded by a filter wall 25. The filters 21 extend over almost a quarter of the total height of the fluidized bed apparatus, so that the exhaust air is cleaned of the product swirling around in the swirling chamber 17. The filters 21 are arranged centrally above the sieve bottom 11. The sieve bottom 11 is delimited by the molded part 4 on the inside and the product container 10 on the outside, with the cylindrical product container 10 widening outwards like a funnel and continuing upwards as the filter housing 20.

Fig. 3 shows a view along section III-III in Fig. 1. In the cylindrical product container 10, the molded part, which tapers further upwards in a conical manner, is

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4. The molded part 4 is initially cylindrical and tapers to a conical point from the level of the sieve bottom 11. The molded part 4 is inclined inwards at the same angle as the outer wall of the housing is inclined outwards from the level of the sieve bottom, so that the ring-shaped sieve bottom 11 is surrounded by side walls tapering like a funnel, which ensure that the product in the vortex chamber 17 is guided back down to the sieve bottom 11. In the product area

12, an inlet 13 and an outlet 14 are provided, with the product flow taking place along the direction of arrow 18. The inlet

13 has a lock system, which is designed, for example, as a double flap, conveyor screw or rotary valve. After flowing through the circular path, the product flow falls into a discharge shaft 19 and is led out through a lock area through the outlet 14. The lock systems must be designed in such a way that they can withstand the pressures that may arise in the fluidized bed apparatus, including explosion pressures.

Fig. 4 shows a further view of the fluidized bed apparatus according to the invention, with the left side of the fluidized bed apparatus shown open, so that a partition wall 15 arranged therein with the weir 16 adjoining it in the lower part can be seen. Otherwise, the same parts are marked with the same reference numbers. The partition wall 15 extends from the container ceiling 22 in the direction of the

Sieve bottom 11, whereby the last area above the sieve bottom 11 is designed as a weir 16. In this area, the partition wall 15 is permeable to a certain extent, so that the product flow can pass through the weir 16 into the next segment after a controllable residence time in this segment. The weir is rectangular and its width is adjusted to the width of the sieve bottom.

Fig. 5 shows a section along the line V-V. In the lower part of the housing 1, the air inlet nozzle 2 leading in on the opposite side is shown in dashed lines and the air introduced through the sieve bottom 11 is shown with the arrows 6. The partition wall 15 ends above the sieve bottom.

11, on which the product layer 12 is arranged. More precisely, the partition wall 15 also ends above the product layer

12. At this end point of the partition wall 15, the weir 16 is arranged in an articulated manner. The weir is rounded or bent at its lower end, with which it comes to rest on the sieve bottom 11, whereby the bend is formed in the direction of the product flow (in Fig. 5 this corresponds to the direction from left to right) in the direction of the arrow 18 and the weir 16 can also be swiveled up in the direction of the product flow, as shown in dashed lines 16a or 16b. The bend that strikes the sieve bottom prevents swiveling in the opposite direction.

Fig. 6 shows a section along the line VI-VI in Fig. 4. It can be seen that a total of three partition walls 15, 15a and 15b are provided here, which divide the product container 10 into three equal segments. A partition wall 15b is arranged between the inlet 13 and the outlet 14, so that these are arranged in different segments. Inlet 13 and outlet 14 are, however, arranged immediately adjacent to the wall 15b separating the two areas, so that the product flow can take place along the arrow 18 over the entire ring surface.

Fig. 7 shows a section along the line VII-VII in Fig. 4, from which it is clear that below the partition walls 15, 15a and 15b in the lower housing part 1, wall elements 5, 5a and 5b are provided, which divide the lower housing part into different segments, whereby these segments correspond to the segments in the product plane, i.e. that the wall element 5 is arranged exactly below the partition wall 15, the wall element 5a exactly below the partition wall 15a and the wall element 5b exactly below the partition wall 15b. In each of these segments, supply air is introduced through an air supply nozzle 2, 3 and 3a, whereby each air supply nozzle has the corresponding independent technical equipment to generate the necessary air conditions.

In Fig. 8, in a first alternative embodiment to the representation according to Fig. 5, a weir 16" is described, which is arranged below the partition wall 15 and whose pivoting

element, not as in Fig. 5 above the product layer, but in the area of the product layer 12 and wherein the weir 16 * is rotatable about the pivot point arranged centrally in the weir 16 ^�Lgr;.

Fig. 9 shows a second alternative to the illustration in Fig. 5, in which the weir is designed in the form of two smaller weir elements 16 ^λλ arranged vertically one above the other. The individual weir elements 16 λλ can be pivoted about a pivot point 16 ^λλ arranged centrally in the weir, comparable to the weir 16 ^λ according to Fig. 8. The individual weir elements 16 ^λλ can also be addressed individually. In a fluidized bed, which has similar properties to a fluid, particles of larger mass sink to the bottom. For example, in fluidized bed spray granulation processes ^, these particles should no longer take part in this process step, but should be fed to a downstream drying or cooling process. By opening only the lower weir, they can be preferentially discharged. In other processes, a granulation process begins with an initial template in a zone. After a certain time, during which the particle size distribution in particular has changed, constant conditions occur. At this point, the upper weir is opened and the product enters this next zone or segment. The lower weir remains closed, creating an overflow effect that ensures constant

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The number and height of the partial weirs used depends on the process requirements.

Fig. 10 shows a third alternative embodiment to the embodiment according to Fig. 5, in which the weir 16 ^λλλ is designed to be displaceable upwards and in this way the lower region no longer rests on the sieve bottom 11.

Claims (17)

1. Fluidized bed apparatus, in particular a continuously operating fluidized bed apparatus for treating powdered or granular products of the pharmaceutical, chemical and/or food industry, with a product container ( 10 ) and with a sieve bottom ( 11 ) provided in the product container, which is supplied with air from below, characterized in that
that the product container ( 10 ) is rotationally symmetrical,
that the product container ( 10 ) has at least one inlet ( 13 ) and at least one outlet ( 14 ) and
that a centrally arranged body ( 4 ) is provided which, together with the rotationally symmetrical product container ( 10 ), defines an annular product flow. 2. Fluidized bed apparatus according to claim 1, characterized in that the fluidized bed apparatus is rotationally symmetrical. 3. Fluidized bed apparatus according to one of the preceding claims, characterized in that the centrally arranged body ( 4 ) has the shape of a cone. 4. Fluidized bed apparatus according to one of the preceding claims, characterized in that the product container ( 10 ) is divided into several segments between the inlet ( 13 ) and the outlet ( 14 ), each segment being assigned an air supply nozzle ( 2 , 3 ). 5. Fluidized bed apparatus according to one of the preceding claims, characterized in that the centrally arranged body has the shape of a cylinder. 6. Fluidized bed apparatus according to one of the preceding claims, characterized in that two or more inlet regions and two or more outlet regions are provided in the product container ( 10 ). 7. Fluidized bed apparatus according to one of the preceding claims, characterized in that each air supply nozzle ( 2 , 3 ) has its own control for adjusting air temperature and other parameters. 8. Fluidized bed apparatus according to one of the preceding claims, characterized in that the fluidized bed apparatus has a housing lower part ( 1 ), a sieve bottom ( 11 ), a product container ( 10 ) and a filter housing ( 10 ) and that these components are designed to be detachable from one another. 9. Fluidized bed apparatus according to claim 8, characterized in that inflatable seals are provided for the detachable connection of the components of the container. 10. Fluidized bed apparatus according to one of the preceding claims, characterized in that dividing walls ( 15 ) are provided in the product plane, which divide the product plane into several segments. 11. Fluidized bed apparatus according to one of the preceding claims, characterized in that a weir ( 16 ) is provided below the partition wall ( 15 ), in the area adjacent to the sieve bottom. 12. Fluidized bed apparatus according to claim 11, characterized in that the weir ( 16 ) is designed to be pivotable to one side at its upper end region. 13. Fluidized bed apparatus according to claim 11, characterized in that the weir ( 16 ') is designed to be rotatable about a central point. 14. Fluidized bed apparatus according to claim 11, characterized in that the weir is formed from two individual weirs ( 16 ") each rotatable about a central point. 15. Fluidized bed apparatus according to claim 11, characterized in that the weir is designed as a height-adjustable weir ( 16 '''). 16. Fluidized bed apparatus according to one of the preceding claims, characterized in that wall elements ( 5 , 5a , 5b ) are provided in the housing lower part ( 1 ), which divide the housing lower part ( 1 ) into different segments, these segments corresponding to the segments in the product container ( 10 ). 17. Fluidized bed apparatus according to one of the preceding claims, characterized in that spray nozzles ( 13 ) are provided above the product level.