DK175962B1 - Agglomeration chamber for agglomerating e.g. milk-coffee medicine etc. - has flexible walls esp. in atomiser region pressurised by cyclically varying fluid sources to create waves discharging agglomerate adhesion - Google Patents

Abstract

An agglomeraged prod. is produced in a chamber with a powder inlet, a ligquid atomiser inlet and a gas inlet. It also has a gas discharge and discharge for agglomerated prod. The chamber has flexible walls, esp. in the atomiser region. In operation, the walls are deformed. The walls include an elastomeric base contacting the outer portion of the wall defining cavities connected individually or in groups with sources of fluid having a cyclically varying fluid pressure. The cycles of one source of fluid are phase shifted with respect to cycles of adjacent sources. Pref. an inwardly facing membrane of rubber or elastomer with a very smooth surface of the side faces into the chamber. The other side of the membrane is supported by a base composed of a number of juxtaposed tubes also made of rubber or elastomeric plastic. These form two groups of channels which are connected to respective sources of compressed liquid or gas, whose pressure is cyclically vaired between 0 and 7 bars absolute. This creates standing waves which deform the membrane in a moving, regular pattern preenting the adhesion of agglomerating particles.

Description

in DK 175962 B1

The invention relates to a chamber for the production of an agglomerated product, which is equipped with one or more approaches for introducing, for example, a powdered substance into the chamber; one or more fluid inlets for introducing a liquid into the chamber; an atomizer disposed therein to "in the form of fine droplets bring the liquid into the atomizer"; a gas inlet duct for supplying the chamber with a gas stream; a gas outlet duct for passing the gas out of the chamber; and a product outlet for guiding the agglomerated product out of the chamber, whereby its space, at least in a zone around the nebulizer, is bounded by a flexible wall and without means being provided to deform the wall during operation.

In products such as e.g. milk, coffee, baking powder, medicine, detergents and chemicals make up the solids content of the essential value.

The residue, which is usually mostly water, is therefore largely separated industrially by, for example, spray drying, where the dry matter is left as fine powdery particles. In this state, the product has a greatly reduced volume, which means that it can be packaged, stored and transported over even great distances in an economically advantageous way. In addition, or easily obtains perishable products such as e.g. milk a long natural shelf life.

However, the fine powder is difficult to work with because it flows poorly and is very dusty. The latter-30th property can be hazardous to health and in some cases even allergic to the persons who come in contact with the dusty product. - -

In order for the consumer to be able to use the product, it must generally be first dispersed or dissolved in a liquid, e.g. often can be water. However, this process is very difficult in DK 175962 B1 2 when the product is in powder form, since the fine particles, due to their minimal extent, are inherently liquid-prone and tend to remain on the surface of a liquid without sink into this one.

a

Therefore, in order to alleviate these disadvantages, the powder is in most cases subjected to an agglomeration process, which consists in principle of wetting the fine particles so that their surface becomes adhesive, after which they are contacted and bonded together. for larger particles or agglomerates. These agglomerates are light-flowing and dust-free and can be easily dispersed and dissolved in a liquid.

15

The agglomeration may e.g. take place directly in connection with an atomization drying in a drying chamber, the fine particles -fine- being recycled back to it; wet zone around the atomizer where the particles are wetted in 20 and agglomerated. However, separate agglomeration vessels may be used, which are pre-dried powders which are also wetted and agglomerated in the wet zone around a nebulizer in the agglomeration chamber.

As part of the agglomeration process, the surface of the particles, as mentioned, is brought into a sticky state and will therefore tend to settle as a coating on the chamber wall if they hit it. This could lead to often costly products being wasted, and the chamber frequently having to undergo troublesome and costly interior cleanups.

For these reasons, it is therefore necessary to build chambers of this kind so large that the chamber wall is kept at a proper distance from the agglomeration zone. This causes the chambers to become costly to manufacture and will take up too much space in the production plant. Furthermore, it is quite difficult to avoid that there are particles to some extent which reach the container wall and adhere to it.

5 * A solution to these problems could be that, at least around the agglomeration zone, a flexible wall is applied, which is successively deformed locally so that any coatings on the wall are loosened and dropped.

10 In doing so, the wall would become self-cleaning.

Such a flexible wall is known from German Patent Specification No. 21 50 708 and U.S. Patent No. 3,887,166, which, however, does not disclose agglomeration chambers, but apparatus for continuously mixing powdered solids with a liquid or granulating such substances by mixing those with a liquid. Below, a plurality of grouped rollers are displaced up and down along the back of a wall, which is successively deformed with indentations, which extend in arcuate form along the periphery, and inward-facing beads extending along generators between these indentations. Therefore, any coating which may have stuck to the flexible wall will be bent during operation by the bends and perpendicularly pressed thereon by the beads. This simultaneous effect effectively detaches the coating from the wall, thus automatically cleaning itself.

In addition to the flexible wall, the two aforementioned known mixing and granulating apparatus are provided with a rotor with blades, which in both cases alone serve to mix and granulate the powdered solids. The blades in the rotor described in the US patent are adjustable to thereby affect the properties of the resulting mixture, the size of the granules and the residence time of the substances in the apparatus.

in DK 175962 B1

Furthermore, from Danish Patent Application No. 3969/83 there is known an apparatus with a chamber which is also equipped with a flexible wall, but which in this case is intended to treat dusty gases in which a liquid is injected to cool and / or otherwise conditioning or reacting with the gases. The flexible wall is hung at the top of the chamber at a relatively small distance from the chamber wall. In operation, a pulsating gas and / or liquid stream is sent into the annular space between the chamber wall and the flexible wall, which should thereby be set in a kind of undulating motion.

Common to the three above-mentioned known constructions is that they are in no case intended for agglomeration of powdery particles and can in no case be used for this purpose. The movements performed by the respective flexible walls are of a kind which alone can cause any coatings to peel off in the form of 20 larger or smaller flakes or lumps which would fall into the agglomerates and be mixed with these, so that the resulting product would become useless or at least not meet the quality requirements that must be set for such products.

25

It is therefore an object of the invention to provide an agglomeration chamber of the type mentioned initially, the flexible wall of which is controlled in such a pattern of movement, that sticky powder particles which hit the wall are agglomerated and repelled in the form of agglomerates of the desired size and quality.

This object is achieved by the new and peculiar of the invention, wherein the means for deforming the flexible wall consists of an elastomeric support which touches the wall of the wall.

exterior and contains a number of voids which are single or J

in

J

j ______-_ in DK 175962 B1 are grouped together individually with a fluid source with a cyclically varying fluid pressure, and the cycles for at least one fluid source are phase shifted relative to the cycles of the other fluid sources. In this way, the 5 flexible wall is set in undulating motion with standing or traveling waves of predetermined height and width. Adhesive powdery particles deposited on the wall will therefore be compressed and agglomerated as the wall moves down a wave valley and the formed agglomerates 10 break apart and bump off as the wall subsequently rises in a wave peak. The chamber can be built with a very small diameter, since its wall now no longer needs to have a large radial distance from the atomization zone, but on the contrary can advantageously be placed close to it.

15

It will be possible with the invention to design the chamber with a more compact construction than hitherto known while maintaining maximum capacity.

Thus, in this context, the flexible wall not only serves to keep the inside of the chamber self-cleaning, but in it additionally forms directly as an important part of the agglomeration process itself. To promote this effect and thereby increase the chamber agglomeration capacity 25, the chamber may advantageously be provided with a rotor having a coaxial shaft with the chamber axis, on which a plurality of arms extending towards the chamber wall are arranged. The rotor puts the gas into the chamber in vigorous circulation, whereby the particles in the gas are affected by a correspondingly large centrifugal force, which safely and efficiently throws the particles onto the wall. The co-produced flows and turbulences in the gas are themselves contributing to the agglomeration. In addition, to some extent, the particles will be agglomerated when directly hit by the arms of the rotor. In this way, it becomes easier to optimally utilize the agglomeration effect on the flexible wall and thereby increase the capacity of the chamber.

The degree of agglomeration, as well as the size and quality of the agglomerates can be affected in various ways by appropriate design of the arms. These may, for example, take the form of blades forming an angle 'with the direction of rotation.

This angle may be adjustable during operation, but may also be predetermined when the blades are fixedly mounted on the rotor shaft.

Chambers of this kind are usually terminated at the bottom of a tapered funnel with such a small top angle that the products can slide unobstructed along the inside of the funnel to an outlet or fluid bed located at the bottom of the funnel.

TEN. This pointed funnel occupies a significant portion of the chamber's overall building height, and in many cases more than 50%. By placing the flexible wall tightly around the atomization zone, the chamber can be designed with a very small diameter. By replacing the pointed taper funnel with a flat or slightly sloping bottom, the overall height of the chamber can be reduced to the height of the cylindrical portion of the chamber in which the actual process takes place. In this case, the flexible wall can be extended to also cover the bottom, which can withstand being hit by sticky particles which are agglomerated and repelled in the same way as in the cylindrical part of the flexible wall. Therefore, the bottom can also be placed close to the agglomeration zone, so that the cylindrical part of the chamber need only have as great a vertical extension as is necessary to carry out the process. The presence of the flexible wall along both the vertical interior side of the chamber as well as its bottom causes such that the chamber can be designed with an extremely compact construction.

35! In this way, when the chamber is terminated below by a planar or slightly sloping bottom which is covered with the flexible wall, the outlet opening of the gas and the product may advantageously be arranged in the side wall in connection to the flexible wall of the floor. and the waves in this are migratory waves running toward the exit aperture. The flexible wall of the bottom will thereby act as a conveyor that carries the agglomerates out of the chamber.

In an advantageous embodiment, the voids in the base of the flexible wall may be in unstressed form as generally rectangular channels which are arranged transversely in at least one row along the flexible wall, and the channels in the row may be divided into groups which are for -15 are each connected to a fluid source, whereby the channels in one group are separated by one channel from each of the other groups, and the channels in the series alternate and the cycles of the fluid sources are phase-shifted in the same group order. This construction means that the wave pattern on the flexible wall 20 can be controlled exactly as desired, and that the wall can therefore produce agglomerates having the required size and quality.

As needed, the ducts may proceed in different ways in the substrate of the flexible wall. Thus, the channels can extend along helical lines, making the channels' connection to the fluid sources particularly simple. In other cases, the channels may advantageously run along a vertical line or with a slope relative to such a vertical line.

30

In a particularly advantageous embodiment, the ducts may be formed of elastomeric tubes which, in the unstressed state, have a generally rectangular cross-section and are arranged side by side. For example, these hoses may be wound up along helical lines and supported by a fixed outer wall of the chamber. Optionally, the hoses may be further adhered to this outer wall. In addition, between the hoses and the flexible wall there may be a negative pressure to keep the flexible wall securely in contact with the hoses.

5

The flexible wall may consist of an elastomeric membrane which has a smooth inner surface with a small coefficient of friction which effectively ensures that the formed agglomerates can escape the wall.

10

It is further to be noted that according to the invention, the channels in the chamber in the unloaded state can have a height of between 10 and 200 mm, preferably between 10 and 50 ram, and a width of between 0 and 50.

15

Furthermore, the flexible wall may have a smooth interior with low coefficient of friction. The flexible wall may also have a thickness of between 0.1 and 10 mm, preferably between 0.5 and 1 mm. In the flexible wall and the substrate, there may be negative pressure. It should also be mentioned that the fluid may be a liquid, e.g. water. The fluid may further be a gas, e.g. air.

Furthermore, according to the invention, the fluid pressure can vary between a pressure of between 0 and 7 bar absolute, preferably between 0 and 2 bar absolute. Besides, the bikes can have one. length between 0 and 5 minutes, preferably between 1 and 2 minutes.

The chamber may be provided with a rotor having a coaxial shaft with the camshaft, on which are arranged a plurality of arms extending towards the wall of the camshaft. In addition, the outer ends of the arm may have a distance from the wall of the chamber between 0.1 and 20 mm, preferably between 0.3 and 10 mm, and the arms may be arranged in sets spaced apart along the shaft.

DK 175962 B1 9

Each arm may, in cross-section, be symmetrical about a tangential plane to the rotational surface described by the arms during rotation. Further, each arm may be configured as a blade which forms a positive angle with the direction of rotation.

It should also be mentioned that the arms may be shaped as blades, some of which form a positive angle and others a negative angle of rotation.

Furthermore, the arms may be formed as blades which alternately form a positive and negative angle with the direction of rotation.

In the case of the rotor being provided with several sets of arms of the form of blades, the blades in at least one of the upper sets can form a positive angle of rotation, and the blades can in at least one of the lower sets of 20 form a negative angle with the direction of rotation.

If the arms of the rotor are shaped like blades, the angular position of the blades may be adjustable during operation.

The agglomeration process itself can be promoted by using a fluid of such a low temperature that the temperature of the inside of the flexible wall comes below the dew point of the chamber. This causes liquid to condense on the flexible wall, which thereby becomes damp. This moisture contributes to making the surface of the powdery particles sticky so that they are more easily bonded to agglomerates. If a quick drying of the agglomerates is desired on the flexible wall, a fluid of such a high temperature can instead be used to keep the inside of the wall suitably warm. The two methods can conveniently be combined, using a cold fluid for the cylindrical part of the wall and a hot fluid for the part covering the bottom. In this way, the agglomeration on the cylindrical part of the wall is promoted, while the resulting agglomerates undergo an appropriate post-drying on the bottom while the "flexible wall" on it transports the agglomerates out of the chamber.

in

The chamber can only serve to agglomerate powder particles which are separately introduced into the chamber and wetted therein by a liquid which is supplied to the nebulizer without any independent dry matter content. However, the solids may also be wholly or partially supplied together with the liquid, as is the case with actual atomization drying chambers. In many cases, the two methods can advantageously be combined.

The invention is explained in more detail below, describing only exemplary embodiments and further advantageous properties and effects with reference to the accompanying drawings, in which: 1 is a schematic sectional side view of a first embodiment of an agglomeration chamber according to the invention having a flexible wall and a pointed conical bottom; FIG. 2 is a schematic sectional side view of another embodiment of an agglomeration chamber according to the invention having a flexible wall and a flat bottom; FIG. 3 is a schematic sectional side view of a third embodiment of an agglomeration chamber according to the invention with a flexible wall, a flat bottom and a rotor; 4 is a sectional view of the embodiment of FIG. 3 on a larger scale, FIG. 5a-d show a larger-scale section through a first embodiment of a flexible chamber wall according to the invention with fluid chambers in four different situations; 6 are curves depicting the flow of pressure in those of FIG. 5a-d channels, FIG. Figs. 7a-d show a larger-scale section through another embodiment of a flexible wall in the chamber of the invention with fluid chambers in four different situations; 8 curves depicting the flow of pressure in those of the one shown in FIG. 7a-d associated channels, FIG. 9 is an enlarged fragmentary sectional view of the lower left corner of FIG. 2 with an agglomerating flexible wall; FIG. 10 is a fragmentary perspective view of a first embodiment of a flexible wall supporting substrate in the form of elastomeric tubes wound up along helical lines; and FIG. 11 is a fragmentary perspective view of another embodiment of a flexible wall supporting substrate in the form of elastomeric tubes vertically disposed side by side. 1 When the chamber below is described and shown in the drawing in a vertical position, i. with a vertical axis, this should only be understood as being, for example. In many cases it will be convenient to place the chamber in this way, but in other cases it will fit better into the production and the associated production plant whose comb.

35 is arranged with a horizontal or inclined axis. · DK 175962 B1 12 In fig. 1 shows a first embodiment of an agglomeration chamber according to the invention. The chamber, which is indicated in its entirety by reference numeral 1, comprises an upper cylindrical portion 2, which enters a lower tapered portion 3; 5 Under this tapered part 3, a lock 4 to j outlet of the finished product is arranged. Dry matter in the form of powdery particles (not shown) is stored in a storage container 5 and supplied to the chamber via a second sluice 6 and a dry solids access 7. In order for the powdery particles to bond together to larger particles in the agglomeration chamber, the chamber must also a liquid is added, e.g. water to moisten the particles and bring their surface into an adhesive state. This liquid is supplied via a fluid inlet 8 to a centrifugal atomizer 9, which is caused to rotate at very high speed by means of a motor 10, so that the liquid is atomized into very fine droplets thrown outwards against the wall of the chamber which is lined with a flexible wall 11, the details of which will be described and described later.

20

The chamber is additionally provided with a gas inlet 12 for passing a gas via a gas distributor 13, e.g. hot air into the chamber to dry the agglomerated product. The gas and the liquid which it has absorbed during the process are again led out of the chamber via a gas outlet 14.

FIG. 2 shows another embodiment of an agglomeration chamber according to the invention. This chamber, which is indicated in its entirety by the reference numeral 15, corresponds, in the main case, to that of FIG. 1, and like parts are therefore indicated by the same reference numerals. The chamber 1 shown in FIG. 1, however, has a bottom in the form of the lower conical part 3, which must necessarily be very pointed to allow the finished agglomerates to slide smoothly off the sides of the cone under the influence of gravity. The small top angle of the cone is offset by a correspondingly large building height, and the one shown in FIG. 1 therefore has a much higher building height than that of FIG. 2, which is provided with a flat bottom 16. The flexible wall 11 is in this case also pulled over the bottom 16. In the cylindrical part 2 of the chamber, a combined gas wall is arranged in connection with the flexible wall 11 of the bottom 16. and product departure 17.

FIG. 3 finally shows a third embodiment of an agio glomeration chamber according to the invention. This chamber, which in its entirety is indicated by the reference numeral 18, corresponds substantially to that of FIG. 1 and 2, the same reference numerals for similar parts are used in this case as well. The chamber 18 is in principle identical to that of FIG. 2, but is now further provided with a rotor 19, which consists of a rotor shaft 20 with a plurality of outwardly extending blades 21 and is rotated up to 3000 rpm by means of a motor 22. Also the detailed arrangement of this rotor function will be explained later.

As shown in FIG. 1, 2 and 3 and described above, the above-mentioned three embodiments of agglomeration chambers are equipped with centrifugal atomizers for atomizing the liquid.

However, within the scope of the invention, this atomization may equally well be effected by other methods such as e.g. two-substance nozzles, pressure nozzles or ultrasound.

In FIG. 5a-d is a first embodiment of the flexible wall depicted in various situations. At the bottom, the wall consists of a membrane 23 which may consist of rubber or an elastomeric plastic and may have a thickness of, for example, between 0.1 and 10 mm. On the side facing the chamber space, this elastomeric membrane 23 preferably has a very smooth surface. Diaphragm '23 is supported on the outside of a substrate, which in its entirety is indicated by reference numeral 14 24. This substrate is made up of a series of tubes which lie side by side and may have a height of no height. of, for example, between 10 and 200 mm and a width of, for example, between 0 and 50 mm. Also, these hoses are made of rubber or an elastomeric plastic. These tubes define two groups of channels 25a, 25b, which are connected to each source of pressure fluid (not shown). The pressure of the pressure fluid sources varies cyclically in the manner illustrated by the curves of FIG. 6, where the pressure in the channels 10 25a is shown in full line and the pressure in the channels 25b in dotted line. For example, the pressure in the ducts can vary between 0 and 7 bar absolute. The cyclically varying pressure in the ducts 25a, 25b causes them to alternately be pumped up and sucked into a very specific pattern which, as shown in FIG. 5a-d are of standing waves, which go through a full cycle of, for example, between 0 and 5 minutes, preferably between 1 and 2 minutes. In order to prevent the diaphragm 23 during this wave movement from contacting the substrate 24, there may advantageously be a negative pressure between these two parts 20. However, the membrane may also be glued to the hoses of the substrate 24, which may also be bonded together.

FIG. 7a-d show another embodiment of a flexible wall in the chamber according to the invention. In this case, the membrane 23 is supported by a support 26 which, like the one shown in FIG. 5a-d are constructed of elastomeric tubes, but in this case with an anterior and posterior series of channels 27a, 27b, respectively; 28a, 28b, 30 are connected in groups to each source of pressure fluid (not shown). This pressure varies cyclically in the same way as in the one shown in FIG. 5a-d · for example between 0 and 7 bar. The variations are illustrated by those in FIG. 8, the upper curves showing the variations in the front channels 27a, 27b, and the lower ones in the rear channels 28a, 28b, and the curves shown in full line in DK 175962 B1 15 indicate the pressure in the the channels 27a, 28a and the dashed dashed curves in the channels 27b, 28b, respectively. The combined effect of these pressure variations causes the diaphragm 23 to be set in a regular undulating motion, but now with migratory waves.

In FIG. 9 is an enlarged cross-sectional view of a detail of the lower left corner of FIG. 2 shows another embodiment of an agglomeration chamber according to the invention. Externally, the chamber is made up of a cylindrical wall 29 and a flat bottom wall 30. In the corner between these walls! in

a rib 31 extends walls 29, 30 and rib 31 I

in, for example, may be made of stainless steel. Internally, the chamber is lined with a flexible wall, which in this case is of the type shown in FIG. 7a-d, with two rows of groups divided into groups 27a, 27b, respectively; 28a, 28b.

20 When the agglomeration chamber is in operation, the powdery particles which are supplied from the storage container 5 are fed to the chamber via the lock 6 and the dry matter inlet 7 of the finely atomized liquid droplets which the nebulizer 9 sends into the chamber towards the flexible wall. Thereby, the surface of the powdery particles becomes sticky, and when the particles hit the flexible wall they will therefore settle thereon as a coating which is indicated in its entirety by reference numeral 32. As can be seen immediately, the coating 32 will be compressed when the membrane 23 30 runs into a wave valley. This causes the particles in the coating to bond together to agglomerates. As the membrane 23 subsequently rises in wave peaks 34, the coating is stretched and the resulting agglomerates are broken apart and detached from the smooth surface of the membrane 23 below.

DK 175962 B1 16

Thus, the flexible wall is not only self-cleaning, calm directly able to independently form agglomerates on its undulating surface. The agglomerates formed on the vertical part of the flexible wall fall onto the 5 part of the flexible wall lining the bottom of the chamber. Since this part of the flexible wall is also agglomerating, the bottom of the chamber can be placed at a relatively small distance from the nebulizer. Thereby, the bottom is also exposed to being hit by powdery particles which, as shown in FIG. 9, 10 are agglomerated in the wave valleys and loosened on the wave peaks. Thus, the bottom surface contributes positively to increasing the chamber's agglomeration capacity. ! i i

The substrate of the one shown in FIG. 9 is of the 15 kind provided with two rows of channels which in operation form migratory waves in the membrane 23. These migratory waves run in the embodiment of FIG. 2 and 9 in the direction of the arrow towards the combined gas and product outlet 17, and therefore acts as a conveyor leading the finished 20 agglomerates out of the chamber via the outlet 17, the waves successively pushing the agglomerates in front of this outlet. The design of also pulling the flexible wall across the bottom of the chamber and making this plan, choosing a flexible wall with waves traveling 25 and transporting the agglomerates to the gas and product outlet, not only causes the chamber's agglomeration capacity to increase, but also that the building height of the chamber can be significantly reduced compared to that of FIG. 1, which is provided with a long pointed conical funnel for guiding the agglomerates out of the chamber.

The capacity of the chamber can be further increased by the means shown in FIG. 3 of rotor 19 during operation, this rotor puts the gas into the chamber in vigorous circulation, whereby they! in powdered particles in the gas is thrown out onto the wall of the centrifugal force and agglomerated. In addition, secondary agglomeration will occur in the turbulent flows in which the rotor enters the gas. In addition, particles directly affected by the rotor blades 21 will be agglomerated.

The leaves are, as shown in FIG. 3 and 4, spaced apart, spaced along the shaft 20 and a distance to the flexible wall of, for example, between 0, 1 and 10 mm. The 10 angle ψ formed by the blades with a plane perpendicular to the shaft 20 is of great importance to the agglomeration process. When the blades, as shown in FIG. 3 and 4 all form a positive angle with the direction of rotation, the rotor acts as an axial fan, which sends a strong central gas flow down through the chamber. This may be advantageous in some cases, while in other cases a less powerful downward central gas flow is desired and in turn a stronger turbulence with high turbulence to promote agglomeration. Such a flow condition can be achieved by, for example, allowing some of the blades to form a positive angle and others a negative angle of rotation, or allowing the blades in the upper set to form a positive angle with the direction of rotation and the blades of the lower set a negative angle. 25 with the direction of rotation. In this way, opposite directed gas flows will occur which, when they meet, form a very severe turbulence and are turned outwards in the direction towards the chamber wall. A similar effect is obtained when the blades alternately form a positive and negative angle of rotation. By forming the blades with a cross-section symmetrical about a tangential plane to the rotating surface described by the blades during rotation, the action of the rotor as an axial fan will be completely eliminated and the rotor alone will put the gas in a swirling and turbulent flow. DK 175962 B1 18

The flow rate in the chamber exerts a significant influence on the agglomeration process and the quality of the resulting agglomerates. This flow course can be carefully controlled when the rotor is arranged so that its blades 5 can be continuously adjusted during operation.

FIG. 10 shows a fragmentary perspective view of a first embodiment of a flexible wall substrate in the chamber according to the invention. The substrate, which is indicated in its entirety by reference numeral 35, is made up of elastomeric tubes 36a, 36b; 37a, 37b, which have a rectangular cross section in the unloaded state. The hoses are arranged side by side in two rows, the hoses in one row being vertically displaced half the height of a hose in relation to the hoses in the other row. The configuration and the grouping of the channels correspond to the one in Fig.

7a-d, and the substrate 35 will accordingly generate migratory waves during operation. Each hose is wound up along a helical line running from the bottom of the substrate 20 to the upper edge of the substrate. This construction means that the number of channels in the substrate is reduced to a few very long channels or tubes which simplify and reduce the number of fluid source connections to the substrate. The structure is particularly suitable for the cylindrical portion of the chamber.

FIG. 11 shows a fragmentary view in perspective of another embodiment of a support for a flexible wall in the chamber according to the invention. Also in this case, the base layer is made up of elastomeric tubes 39a, 39b; 40a, 40b, which have a rectangular cross section in the unloaded state. The hoses are arranged side by side in two rows in the same manner as in the one shown in FIG. 10, but extend vertically between the top and bottom edges of the substrate. Also, this substrate will generate migratory waves in the elastomeric membrane upon which the agglomerates are formed, but waves will occur. preferably now extend longitudinally along the membrane's generators. This may be advantageous when the substrate is used in an oblique agglomeration chamber, as this construction allows the resulting agglomerates to be prevented by transverse waves sliding down the inclined interior of the membrane.

In the unfolded state, the one shown in FIG. 11, the other embodiment shown is suitable for laying on top of the planar bottom 10 in the embodiment shown in FIG. 2 and 3 show agglomeration chambers. The hoses must then be placed longitudinally across the gas and product outlet 17, and the waves move towards it. In addition to participating in the agglomeration process, an elastomeric membrane with a substrate of the one shown in FIG. 11 we-15th species 38 will therefore simultaneously act as a conveyor that safely and efficiently carries the finished agglomerates out of the chamber.

The cavities, ducts or tubes may be grouped together into the respective fluid sources via separate manifolds (not shown). The fluid, which may, for example, be air or water, can only serve as a medium for deforming the flexible wall. In this case, the connections may advantageously take place at one end of, for example, every 25 hoses. The fluid will then, essentially during operation, only pulsate back and forth in the hose and soon enter the same temperature as the flexible wall. The fluid used will then have no effect on the temperature course of the flexible wall. This temperature course is determined solely by the production parameters inside the chamber, including in particular the temperatures of the gas, liquid and powder particles. · -

Otherwise, the temperature of the fluid, as previously mentioned, is supposed to help control the agglomeration process on the flexible wall. In this case, one end of, for example, a hose may be connected to an overpressure source and the other to an underpressure source, whereby overpressure and underpressure must be understood in relation to a mean pressure. Thereby, the fluid contained in the tubing will be successively replaced by new fresh fluid which in this way can sustainably maintain the wall at the desired temperature by either absorbing or delivering heat to the wall.

FIG. 5a-d and fig. 7a-d show two preferred embodiments of a base wall for a flexible wall in the chamber of the invention. The FIG. The -5a-d substrate shown is distinguished by its simple and inexpensive construction. The generated waves are standing and this causes the membrane 23 to not completely deform across the waves. Thus, the membrane deforms most in the mid region of the waves and to a lesser extent in the transition area between the waves. Thereby, agglomerates are formed which are quite dissimilar in size, and this can be advantageous in some cases, since the 20 finished agglomerates can thereby be packed closer together.

The FIG. 7a-d, with two rows of tubes 26, on the other hand, the membrane 23 deforms completely uniformly with traveling waves. Thereby, a product with more uniform size agglomerates is obtained.

25

However, the invention is not limited to the two of FIG.

5a-d and fig. 7a-d show one and two rows of ducts or hoses respectively. Thus, depending on the wave formation desired on the membrane 23, there may be both three and more rows of channels or tubes, and the channels in each row may be divided into more than two groups. In order to achieve a regular wave motion, it is important that the channels in one group are separated by one channel from each of the other groups and that the channels in the series 35 alternate and the cycles of the fluid sources are phase-shifted in the same group order. In all the embodiments of the flexible wall substrate described above and shown in the drawing, the cavities or channels in this have the same cross-section. However, embodiments within the scope of the invention can be conceived conceivably, where the voids or channels in each row and / or row by row have at least partially different cross sections in order to thereby generate precisely the wave pattern desired on the flexible wall. .

Claims (9)

A chamber (1, 15, 18) for producing an agglomerated product and equipped with one or more approaches (7) for introducing, for example, a powdered substance into the chamber (1, 15); one or more fluid inlets (8) for introducing a liquid into the chamber; a nebulizer (9) disposed therein in the form of fine droplets to bring the liquid 10 in a nebulized state; a gas inlet duct (12) for supplying the chamber with a gas stream; a gas outlet duct (14) for passing the gas out of the chamber; and a product outlet (4, 17) to guide the agglomerated product out of the chamber, whereby its space is at least in a zone around the nebulizer bounded by a flexible wall (11), and means for which it is arranged below operation to deform the wall, characterized in that the deforming means consist of an elastomeric support (24, 26) which touches the outside of the wall and contains a number of cavities (25a, 25b; 27a, 27b; 28a, 28b) which are single or grouped connected to each fluid source with a cyclically varying fluid pressure, and the cycles for at least one fluid source are phase shifted relative to the cycles of the other fluid sources. A chamber (15, 18) according to claim 1, characterized in that the chamber (15) has a flat, horizontal or relatively slightly sloping bottom and an outlet opening (17) located in the wall of the chamber (15, 18). ) to the agglomerated product and the gas; this bottom is covered by the flexible wall (11); and that the deforming means are arranged to at least set this part of the wall in undulating motion with traveling waves running towards the outlet opening (17). DK 175962 B1 23 Chamber (1, 15, 18) according to claim 1 or 2, characterized in that the flexible wall consists of an elastomeric membrane (24, 26). Chamber (1, 15, 18) according to one or more of claims 1 to 3, characterized in that the voids in the unstressed state are in the form of generally rectangular ducts arranged transversely in at least one row along the flexible wall. 10 Chamber according to one or more of claims 1-4, characterized in that the channels in the series are divided into groups which are connected to each fluid source and that the channels in one group are separated by a channel from each of the other groups. , whereby the channels in the row alternate and the cycles of the fluid sources are phase-shifted in the same group order. Chamber according to one or more of claims 1 to 5, characterized in that the channels in each row are divided into two groups. Chamber according to one or more of claims 1-6, wherein there are at least two rows of channels of equal cross-section, characterized in that the center of the cross sections in one row lies midway between the cross sections in the adjacent row. Chamber according to one or more of claims 1-7, 30, characterized in that there are two channel rows, each divided into two groups and that the cycles of each series of fluid sources are phase-shifted at equidistant time intervals relative to the cycles of the closest group in the 35 neighboring row. DK 175962 B1 2 4 Chamber according to one or more of claims 1-8, characterized in that the channels each extend along a helix with an increase corresponding to the distance between the center of two adjacent channels in the series multiplied by the number of groups therein.