EP4319919A1

EP4319919A1 - Wetting machine for cereal grains

Info

Publication number: EP4319919A1
Application number: EP22720610.9A
Authority: EP
Inventors: Andreas Stöppler; Georg STÖPPLER
Original assignee: Swisca Ag
Current assignee: Swisca Ag
Priority date: 2021-04-08
Filing date: 2022-04-01
Publication date: 2024-02-14
Also published as: JP2024516509A; US20240181464A1; AU2022254185A1; CA3214030A1; WO2022214401A1

Abstract

The invention relates to a wetting device (1) for cereal grains comprising a container having a container inlet (11) and a container outlet (12), which are arranged in such a way that cereal grains flowing into the container inlet reach the container outlet due to the effect of gravity. A plurality of nozzles (36, 37) function to wet the cereal grains inside the container. The wetting device also has a flow directing device, e.g. formed by impact elements, inside the container, which shape a flow of the cereal grains flowing into the container inlet and falling downwards. The nozzles (36, 37) are arranged such that liquid or vapour exiting same sprays the cereal grains below the flow directing device, while the cereal grains are in free fall.

Description

WETTING DEVICE FOR GRAIN GRAINS

The invention relates to a device for wetting cereal grains for the purpose of subsequent further processing into a ground product.

In milling plants, grain products are sprayed (moistened/wetted) with water for subsequent processing. The wetting process is necessary so that the corn shell can be better detached from the endosperm. This makes the grinding more even and the yield higher. According to the state of the art, the best possible mixing of the cereal grains with the water is achieved after spraying by mechanical processing, generally in a screw conveyor. Corresponding wetting devices in grain mills usually have horizontal rotating shafts with a wide variety of mixing installations for this purpose. The grain kernels flow continuously into this apparatus. At the same time, a defined amount of water is metered into this device. The grain is mixed with the free water by means of the rotating shafts and their stirring and mixing elements. After wetting, the cereal grains are conveyed into a so-called settling cell, where they are left for some time, usually a few hours, before they can be processed further.

In terms of their function and structure, such wetting devices should not be confused with cleaning systems such as those used in modern industrial mills upstream process, and which aim to remove impurities from under the grain kernels, among other things by separating cleaning water with the impurities dissolved in it after the process. In practice, in addition to good wetting properties, the important process step of wetting in a grain mill also has other functions. The germ contamination of the grain by the field flora, which inevitably ends up being ground by the grain mills, is unavoidable. The interior of a wetting device offers microorganisms and germs an ideal breeding ground for their growth. Therefore, the internal cleanability of the wetting device - as well as other devices in a mill system - is an essential requirement.

Wetting devices according to the prior art have the disadvantage that a mechanism is required for the mechanical mixing of the grain kernels, but it is difficult to clean. In particular, the cleaning of the mixing elements and the mixing chamber, in which there are constantly moist grain kernels and other residues during operation and thus correspondingly adhering to them, is laborious and is therefore often disregarded.

It is therefore an object of the present invention to provide a wetting method and apparatus for grain kernels which overcomes disadvantages of the prior art. The wetting device should, in particular, be simple in construction and therefore involve as little production and maintenance effort as possible. Additionally or alternatively, it should be easy to clean. The wetting process should be such that a corresponding structure of the wetting device that is as simple as possible is possible. This object is achieved by a wetting device, a method and a mill system as defined in the patent claims.

The invention is based on the approach that a (defined) falling stream of grain kernels is generated inside a container, and that these grain kernels are mixed with a liquid and/or steam (i.e. with water or steam, with water as required with additives) as they fall enriched) are sprayed.

The temperature of the water can be set to any required value during the spraying process, i.e. between 0°C and 100°C. The temperature and pressure of the steam are also not fixed at a fixed operating point and can vary.

The fact that the cereal grains are sprayed and/or steamed 'as they fall' means that the liquid in the form of fine droplets or the steam hits the grain kernels while they are falling and not, for example, only when the grain kernels are on a substrate have encountered. This procedure, in contrast to spraying grains that lie flat or are conveyed and/or mixed by mechanical means and that form a mass of grains in contact with each other (grains in bulk), allows substantially all the grains to be treated immediately come into contact with the wetting fluid (liquid and/or vapor) during spraying and/or steaming. Therefore, a subsequent mechanical mixing of the grains is not necessary. Mechanical mixers that are difficult to maintain and clean, such as screw conveyors, can be omitted. Rather, the Wetting device should be free of actively driven parts that are in contact with the grain and move it mechanically.

The temperature of the water during the spraying process is between 0°C and 100°C. If the wetting takes place at least partially by steaming, the temperatures and pressures of the steam are not fixed at an operating point and can also vary.

The mill system can, for example, be constructed in such a way that the cereal grains, possibly after a short dwell time in the container, at least without subsequent mechanical mixing, go directly from the wetting device into a holding cell, solely due to the gravitational effect when the holding cell is below the wetting device , or merely by pneumatic means if it is above or at the same level as the wetting device.

The falling stream of grain kernels can in particular be curtain-like, locally flat, i.e. form a flat contour in a horizontal section. In this way, essentially all grain kernels can be wetted by spraying and/or steaming, for example from two sides.

In particular, the downdraft is vertical. This makes it possible for the falling stream to be controlled particularly well, both with a large grain throughput and when the grain throughput is smaller - the wetting works without the grains having to be given a horizontal impulse. The spraying and/or steaming can take place through suitably arranged nozzles. In particular, these can be arranged in such a way that essentially the entire downflow is wetted.

In particular, the downflow can form a hollow cylinder, for example essentially a hollow circular cylinder, with blade projections protruding radially outwards. Such a downflow is star-shaped in horizontal cross-section, ie a circular ring with jets projecting outwards from it, and it therefore has a particularly large surface for simultaneous spraying and/or steaming from the inside and from the outside. Quite generally, by designing the flow guide device with radially running segmenting elements, a downflow can be generated which is segmented, for example by forming radially running jets in the horizontal cross section. As a result, the surface is particularly large, and in particular nozzles acting from the outside and distributed along the circumference of the container can wet particularly efficiently, for example by being arranged between the segments in the circumferential direction (azimuthally). For this purpose there can be at least three outer nozzles distributed along the circumference, i.e. there is one outer nozzle each at at least three different azimuthal positions. In particular, there can be at least one outer nozzle for each intermediate space between outer (radial) impact elements.

Regardless of the exact shape of the tumble stream, the wetting device can have inner and outer nozzles. For example, the internal nozzles may be located approximately on the axis of the container. External nozzles may be arranged along the vessel wall, e.g. on several levels, e.g. on a feed line, forming one or more horizontal circumferential rings. Such an arrangement with inner and outer nozzles has the advantage that the structure is particularly simple and that no elements potentially impeding the downflow protrude into it - at the level of the spraying, the interior space can be reduced to the centrally arranged inner nozzles and elements Supply be completely free.

However, it is also possible to provide other arrangements of nozzles, for example on a linkage, which holds the nozzles at the desired, demand-optimized positions.

The nozzles, in particular the inner nozzles where appropriate, but possibly also the outer nozzles, can be designed as fan jet nozzles in order to enable a relatively wide spray angle.

In particular, the contoured downdraft is formed by flow directors located within the vessel, generally above the nozzles. Through an inlet--which can be closed in a conventional manner by an inlet slide or an inlet flap--the grain decomer stream entering the container is shaped by the flow control device in a desired, surface-optimized manner. The flow control device decelerates and shapes the vertical flow of grain grains in such a way that a falling flow that is as easy as possible to wet with a large surface area (mantle surface) is created. The falling stream is sprayed below the flow director, at a position where the granules are in free fall. The flow guiding device thus divides the interior of the container into a collecting area above the flow guiding device and a falling area below the flow guiding device.

In particular, the following can therefore apply:

• The grains are only sprayed while they are falling below the flow guide and not, for example, while they hit the flow guide or slide along it for a distance.

• The grains are only deflected on one level of the flow deflection device, and from there they fall through the interior of the container without being subjected to any further deflection. In contrast to arrangements with, for example, cascade-like guide surfaces, there can also be no rooms shielded from the flow guide device, which would be difficult to clean. The wetting device can in particular be designed in such a way that the grains can fall in free fall downwards directly from the flow deflection device onto a container wall delimiting the container at the bottom or, depending on the passage, onto grains already collected and heaped up there, without the need for further deflecting elements, screens or similar would be available. Below the collection area and the drop area, for example in a central part of the container, a buffer space can be formed adjoining the drop area, with the drop area being able to merge into the buffer space without a clear delimitation being defined and visible. At the bottom, the container is delimited by an outlet, which can also be closed in a manner known per se by an outlet slide or an outlet flap. Such a flow control device can initially have a central baffle element, the dimensions of which are matched to the inlet in such a way that essentially all grain grains flowing in through the inlet hit the central baffle element - or, in the case of a backwater, grain grains that have already been backed up - and are prevented from falling directly from the Inlet unchecked to fall down through the container. Sometimes the central baffle is dimensioned and arranged so that it lies in the line of fall below the inlet and covers its entire cross-sectional area (in a projection along the vertical). The impact surface pointing upwards can, in particular, be convexly curved and, for example, rotationally symmetrical about the vertical axis, in order to deflect the grain kernels uniformly in all directions.

The flow guide device can also have radially running segmenting elements (outer impact elements) which structure and segment the downflow in an outer area in the circumferential direction, so that the aforementioned jets are formed in the horizontal cross section. These outer impact elements can also be arranged so as to rise outwards, that is to say form a base which tapers down towards the axis and is interrupted towards the center and by intermediate spaces between the impact elements. In the event of a particularly large grain flow and a back pressure caused as a result, the radius of the jets will therefore automatically increase, which is why the flow control device acts in a self-regulating manner: with a greater grain flow, the surface area of the downflow increases, while the density of the grain kernels and the thickness of the downflow contours increase remains the same, and so the efficiency of wetting is not impaired. The outer impact elements can, in particular, have the form of wings that are curved upwards or taper upwards towards an edge, the width of which increases radially outwards and the tip of which rises radially outwards. In particular, the impact elements are arranged in the wetting device in such a way that they do not have a function that loosens the fruit peel - i.e. the wetting process is gentle, and the impact speed on the impact elements - and also on the collecting surfaces in the lower area of the wetting device, on which the grain kernels fall after the wetting fall - are shaped and arranged in such a way that the impact speeds of the grain kernels are correspondingly moderate and no mechanical processing of the grain kernels takes place.

The container can in particular be cylindrical in certain areas, for example with a circular cross-section. It can, for example, have a central cylindrical area, which also includes, among other things, the area in which the spray mist of the spraying liquid or the vapor meets the falling stream of grain kernels. A conical inlet or outlet area can be present on the top and bottom, which tapers continuously towards the inlet or outlet. The inlet and/or the outlet can be arranged centrally, i.e. their respective central axis can coincide with a (vertical) central axis of the container. The vertical central axis of the container is sometimes simply referred to as "axis" in this text.

Regardless of the cross-sectional shape of the container, the wetting device can be designed so that there are no internal surfaces for grain to lodge on. In particular, the container does not form any inner upward-pointing surfaces (shoulders or the like), and with the exception of the impact elements, which only have curved and/or inclined surfaces, there are no elements with further upward-pointing surfaces inside the container . However, it can optionally be provided that the wetting device is controlled in such a way that the wetted cereal grains are backed up in the lower part of the container for a short time (typically a few seconds, for example 8-30 s). This can - if required - have a moisture balancing effect, in addition to moisture balancing in the soaking cell located below.

The accumulation in the container base can be done with the help of an accumulation control device (an accumulation control member). A shut-off device is referred to as a "backwater control device" here, which is controllable in the sense that it can not only be switched between two states ("open" and "closed"), but also allows different flow rates to be set. Examples of such accumulation control devices are accumulation control flaps or outlet slides.

The accumulation gelling device is set up in particular to regulate the grain mass flow of the wetted grain kernels as a function of the accumulated level. In particular, a backwater control valve can be advantageous in that such, in contrast to an outlet slide, prevents the

Grain grains flow out of the container asymmetrically, so that there are regions in the accumulated product that remain in the container for a very long time and only a partial mass flow falls out of the container. In one example, a backwater control flap with two (or possibly more than two) flap wings is used, which in the closed state each covers a part of the

complete the flow cross section. The use of several flap wings ensures a particularly even outflow of the grain kernels, even if the overflow control flap is only partially opened.

For the purpose of accumulation control also at least one level sensor may be present, through which reaching a level of a Grain level can be determined above the accumulation control device. The at least one level sensor can enable the level to be measured, or it can act discretely, ie, for example, determine when a specific, predetermined level has been reached. In both cases there can also be a plurality of level sensors, with the different level sensors being fitted in the second case in such a way that they detect different level heights.

The backwater control device can be integrated together with the at least one level sensor in a control loop, which regulates the level according to specifications by setting the flow rate through the backwater control device (in the case of a backwater control flap by the position of the flap or flap wing), with the specification of parameters ( e.g. properties of the product, desired humidification, temperature etc.) and/or on settings made by the user.

A backwater control flap - or an outlet slide - can be clamped between two mounting flanges so that the flap or slide can be dismantled at any time.

The provision of an accumulation control device - in particular together with level sensors, in particular together with a control as discussed here - is an option for wetting devices in general, ie wetting devices for grain kernels with a container (with a container inlet and a container outlet), and with at least one nozzle for wetting the grain inside the container. The container can, for example, be in two parts, with a container upper part and a container lower part. The upper and lower parts of the container can be fastened to one another via a flange connection. Particularly in embodiments in which a cleaning device is present, it is generally not necessary for the upper and lower parts of the container to be separable from one another with little effort.

An optional but often particularly advantageous cleaning device has, for example, a plurality of cleaning spray balls and/or cleaning lances. Such cleaning spray balls or cleaning lances can be positioned in a fixed manner or, particularly in the case of cleaning lances, each have an element that can be extended into the interior of the container and carries at least one cleaning nozzle. The cleaning lances can be designed in such a way that they are automatically extended due to the water pressure as soon as the cleaning lances are supplied with cleaning water. As an alternative to automatic extension due to the water pressure, pneumatic actuation or another extension mechanism is also conceivable. It can also be retracted automatically after cleaning has taken place, for example due to spring force or pneumatically.

A cleaning device of this type can in particular optionally have at least one - generally a plurality, for example three each - cleaning lance(s) or cleaning spray balls with cleaning nozzle(s) in the (upper) collection area and at least one - also generally a plurality, for example three -

Have cleaning lance(s) with cleaning nozzle(s) in the fall area. Additional cleaning nozzles, possibly on additional cleaning lances, can be provided, for example if the area below the flow guide device has appropriate dimensions. The container and the cleaning device can be matched to one another in such a way that internal cleaning can be carried out without spray shadows. In a lower area, the container can have a container emptying connection. Such a container emptying connection can be closed in a manner known per se by an outlet ball valve or an outlet flap. The cleaning agent (typically cold or hot water) is discharged from the container via the container emptying connection. Additionally or alternatively, the container emptying connection can be integrated into the outlet flap or the outlet slide and, for example, the outlet flap or the outlet slide can have an opening for residual cleaning water, which has a perforation, for example, through which residual cleaning water can be discharged. In particular, the wetting device can have a (specially designed) outlet flap which can be switched between a closed and an open state and which, when closed, prevents cleaning liquid from flowing inside the container through the container outlet, but which has a hollow shaft and an opening , which is open towards the container interior when closed, and which is connected to the hollow shaft. When the outlet flap is closed, cleaning liquid can then be discharged from the interior of the container through the opening and the hollow shaft without it flowing through the container outlet.

The cleaning takes place in particular during breaks in operation when no grains are fed to the wetting device. This means that the wetting device is set up not to release any cleaning liquid during the wetting operation when the wetting nozzles are in operation and grains are fed in through the container inlet. Rather, the wetting device is set up to convey liquid through the cleaning nozzles in a dedicated cleaning operation. A cleaning device of the type described with nozzles arranged inside the wetting device and/or which can be extended into the interior of the wetting device for spraying the inner wall of the container and/or other elements arranged inside the container is - in particular together with an outlet flap of the type mentioned, through which cleaning liquid can be discharged - an option for wetting devices in general, ie

Wetting devices for cereal kernels with a container (with a container inlet and a container outlet), and with at least one nozzle for wetting the cereal kernels inside the container. The wetting device is operated in such a way that wetting with the desired amount of liquid is effected. This means that at no time is excess water supplied that would have to be excreted from the system. For this purpose, a controller - which belongs to the wetting device or to a higher-level unit, e.g. the entire mill system - can monitor both the grain flow rate and the amount of sprayed liquid or steam and at least meter the latter. The dosing takes place in such a way that exactly the required amount is dosed. This is generally between 0.5% and 12% of the grain quantity (in percent by mass), which is orders of magnitude smaller than, for example, in grain washers.

In order to determine the required dosage, a system having the wetting device can, in addition to the wetting device, also have a measuring device for measuring the actual grain moisture content of the respective grain grain batch. Such a system detects the moisture content of the grain grains inline before the wetting process using measuring devices (inline moisture sensors). From this, the controller calculates the necessary amount of water to be wetted. In addition to the wetting device and the method for operating a wetting device, a mill system is also part of the subject matter of the present invention. Such a device has devices of the type known per se - e.g. a roller mill and screening devices as well as a weighing and/or dosing device and a conveyor device - and additionally a wetting device of the type described here . In particular, the mill system can be designed in such a way that there is no mechanical mixing of the grain kernels between the wetting device and the fermentation cell and no mechanical conveying means with physical contact acts on the grain kernels - which does not rule out the presence of an optional pneumatic conveyance (conveyance in the gas stream).

Exemplary embodiments of the invention are described below with reference to drawings. In the drawings, the same reference numbers indicate the same or analogous elements. The drawings partially show corresponding elements in different sizes from figure to figure. Show it:

1 and 2 show a wetting device in a perspective view and in a side view, respectively;

Fig. 3 is a view of the wetting device of Figs. 1 and 2, sectioned along the plane E-E of Fig. 2;

4 shows a view of the wetting device according to FIGS. 1-3 cut along a horizontal plane lying above the impact elements; 5 shows a view of the upper part of the container of the wetting device according to FIGS. 1-4, sectioned along a vertical plane;

6 shows a perspective view of the horizontal tube, vertical tube and the central impact element of the wetting device according to FIGS. 1-5; FIG. 7 is a diagram of a wetting device with a stand-off cell; FIG.

8 and 9 a further wetting device in a perspective view and in a sectional illustration; and

- Figures 10-12 details of the wetting device according to Figures 8 and 9.

An example of a wetting device 1 is shown in FIG. 1 in a perspective view and in FIG. 2 in a side view. The wetting device has a container which is formed by a container upper part 2 and a container lower part 3, which are connected to one another by a flange connection. The flange connection is formed by an upper flange ring 4 and a lower flange ring 5, which are screwed together when ready for operation. As will be explained below, the flange connection does not have to be loosened to clean the wetting device.

The upper container part 2 forms an inlet 11 and the lower container part 3 forms an outlet 12, which are, for example, aligned with one another and are arranged straight one below the other in the line of fall. Inlet and outlet are each arranged centrally in the illustrated embodiment, ie their vertical axis coincides with the axis of the container together. They are generally designed in such a way that they can be easily coupled to upstream or downstream elements of a mill system, e.g. containers, dosing systems, pipelines, etc. For this purpose, an inlet or Outlet coupling structure (e.g. a corresponding nozzle) must be available. In addition, there is a closing inlet flap or outlet flap or a corresponding slide or another shut-off device at the inlet and at the outlet, for example. In the illustrated embodiment, the inlet flap 13 and outlet flap 14 can each be operated manually, with a corresponding operating lever 15 or 16. The container has a container wall formed by the container upper part 2 and the container lower part 3, which essentially forms a body of revolution with a vertical axis 20 . In a central area, the container wall is cylindrical, conical towards the inlet 11 and towards the outlet 12 .

As can be seen in FIG. 3, for example, a central impact element 21 is arranged below the inlet 11. This forms an upwardly directed, convexly curved impact surface 22. Radially outside of the central impact surface are also shown in Figures 4 and 5 outer impact elements 23 are present, which are each formed by a pair of roof-like ramps and form a radially extending, radially outward slightly rising crest, from which to both sides depending on the descending ramp. As can be seen particularly well in the plan view according to FIG. 4, the width of the impact elements increases radially outwards, so that the gaps 24 between them form radially extending gaps, the width of which increases only slightly radially outwards and remains almost constant .

The wetting device also has a plurality of nozzles through which the liquid is sprayed onto the falling grain kernels. A first set of nozzles is formed by the inner nozzles 36 through which the liquid is sprayed radially-outwardly from an approximately axial position. The inner nozzles 36 can be seen not only in FIG. 3 but also in FIG. The vertical tube also carries the central baffle element 21, which is therefore attached to the container bottom part 3 in the embodiment described here, in contrast to the outer baffle elements that are present on the container top part. The horizontal tube 31 runs transversely through the container and carries the vertical tube 32. The horizontal tube is supplied with the liquid from one side via a container puncture. At the point where the vertical tube 32 is fastened, there is also a branch 35, for example. Some of the liquid is then transported from there through the horizontal tube and on the side opposite the container puncture through another container puncture into a bracket-shaped transition pipe 33 (Fig. 2). and from there to the nozzle ring of the outer nozzles 37. Other ways of guiding the liquid to the nozzles are also possible, e.g. without branching, in which case the liquid then passes e.g. through the vertical tube up to the inner nozzles and from there down again inside the vertical tube, or with a transition between inner and outer nozzles inside the container instead of the transition tube 33, with liquid supply via the outer nozzles to the inner nozzles instead of vice versa, with separate liquid supplies for the inner and outer nozzles, etc. Many other ways of supplying liquid to the nozzles are conceivable.

The inner nozzles 36 are designed as fan jet nozzles which spray the liquid at a wide angle such that the inner nozzles together substantially completely spray an annular area (ring diameter: slightly larger than the diameter of the central baffle) around them. The outer nozzles 37 are arranged in a ring and spray from the outside inwards. The outer nozzles can also be fan jet nozzles, with the spray angle being, for example, less large than in the case of the inner nozzles. The azimuthal position of the individual outer nozzles can be matched to the corresponding position of the outer baffle elements, in that each outer nozzle sprays a space which lies below the space between each two adjacent outer baffle elements and through which the grain grains falling downwards flow.

Like the inner nozzles 36, the outer nozzles 37 are arranged approximately at the level of the flange connection between the upper part 2 and the lower part 3 of the container.

Cereal grains fed into the wetting device from the inlet 11 fall onto the central impact element 21 and are deflected from there radially outwards. The grain flow is then segmented in an outer area by the outer impact elements 23 . The grain flow is thus shaped by the space between the impact elements 21, 23. In horizontal cross-section it has the shape of a ring with rays projecting radially outwards, as can be seen particularly well in FIG. 4; overall there is a mass flow with a star-shaped cross-section. Both the ring and the jets are relatively thin, so that grain kernels can never be shielded from the nozzles by other grain kernels to any appreciable extent.

The slight rise outwards of the crests of the outer impact elements ensures a controlled distribution in the radial direction, even with different flow rates and different speeds of the incoming grain grains hitting the central impact element. With a larger mass flow rate a certain backwater can also form. This is automatically controlled by the fact that when the collection area above the impact elements is filled to a greater extent, the cross-section of the mass flow below the impact elements increases if more grain grains are accumulated. This happens automatically in that the areas through which the flow passes extend further radially outwards when more grain kernels are accumulated by the impact elements and the area above the impact elements 21, 23, which tapers slightly towards the center, begins to fill up. This ensures that, even with a high mass throughput, the grains are always distributed in such a way that they only form thin curtains of grain flow. Irrespective of the mass throughput, the spraying with the liquid will therefore always reach substantially all grain kernels. As a result, no mechanical mixing is necessary after spraying, even with a large mass throughput.

Accordingly, the mill system can be designed in such a way that the wetting device 1 is followed directly by a standing cell 101, which is shown schematically in FIG. The standing cell 101 can be arranged directly below the wetting device 1, or alternatively, pneumatics (with at least one blower/compressor etc.) acting directly on the grain kernels can promote the flow of grain kernels from the outlet of the wetting device to the inlet of the standing cell. In any case, there is generally no screw conveyor or the like between the wetting device and the standing cell, which would be expensive to maintain and clean.

When the mill system is in use, the cereal grains pass from a store through the wetting device into the standing cell and from there - after a standing time of a few hours, e.g. 8-16, chosen according to need hours - into the other elements of the mill, in particular the roller mill, screening devices, etc.

An—optional—special feature of embodiments of the wetting device according to the invention is the presence of an integrated cleaning device. This has a plurality of cleaning lances 41, 42, namely a plurality of upper cleaning lances 41 for the space above the impact elements 21, 23 and a plurality of lower cleaning lances 42 for the space below the impact elements 21, 23. The cleaning lances each have an ins Container interior extendable nozzle element, each with at least one cleaning nozzle. The extendable nozzle elements can optionally be designed in such a way that they automatically extend inwards, for example against a spring force, as a result of the effect of the water pressure as soon as water is fed into the cleaning lances. They are arranged in such a way that when the nozzle elements are fully extended, essentially the entire interior of the container is sprayed if the cleaning water is fed in with sufficient pressure.

For the purpose of cleaning, at least the outlet flap is closed, for example, and water is fed under pressure into the cleaning lances 41, 42, whereupon the nozzle elements extend and the cleaning nozzles spray cleaning water at the inner end of the nozzle elements, whereby the entire interior of the container including the surfaces of the Impact elements is sprayed. The cleaning water with the washed-off cereal grain residues is discharged via a—closable—container emptying connection 51 (outlet nozzle).

Even if the container emptying connection 51 is arranged directly above the outlet flap 14, a small amount of residual water remains on the outlet flap 14 even after emptying. Provided these Amount of water is relevant for the user, the wetting device can be set up to discharge this residual amount of water. For this purpose, for example, a shaft that supports the outlet flap or a wing of the outlet flap can be a hollow shaft with a perforation at the top. The remaining water can then be discharged through the hollow shaft.

A further embodiment of a wetting device is shown in FIGS. The mode of operation of the flow control device with central impact element 21 and outer impact elements 23 and the spraying is analogous to the embodiment of FIGS. 1-6. The wetting device 1 of FIGS. 8 and 9 is provided with a mechanism which enables a controlled accumulation of the wetted grain kernels in the lower part of the container, as a result of which a moisture balance between the grain kernels can be effected if necessary. For this purpose, a backwater control flap 72 is present in the illustrated embodiment. Regulation via an outlet slide would also be possible.

FIG. 11 shows a section through the backflow control flap 72 . This figure shows the control damper in the closed position. The accumulation control flap 72 has essentially identical, symmetrically arranged flap wings 73 (flap halves), which evenly regulate the entire grain mass flow. The flap wings 73 are adapted to the contour and their position is adjusted by means of a servo motor (servo actuator 71). When opening, the flap wings (73) rotate in opposite directions about their flap axes, represented by concentric circles in the sectional view according to FIG. Due to the symmetrical position of the flap halves, zone formation or an irregular grain mass flow to the outlet center is avoided.

The filling level of the bottom part of the container is regulated by means of level sensors 75, which detect the product that has already been wetted and accumulated. For this purpose, the controller (not shown in the figures) of the wetting device or the higher-level unit has, for example, a control loop which regulates the level according to specifications by the position of the backwater control flap 72 .

In the example shown, the accumulation control flap 72 is clamped between two fastening flanges 74 so that the flap can be dismantled at any time—but this is not essential for the function of the accumulation control flap 72 .

During cleaning, the accumulation control flap 72 is, for example, fully opened.

Another special feature of the embodiment of Figs. 8 and 9, which is independent of the accumulation control flap, is the specially developed outlet flap 14, which is designed specifically for wetting devices with a cleaning device and can generally be used in such (i.e. also in embodiments of the devices shown in Fig. 1-6 illustrated species). A section through the outlet flap 14 is shown in FIG. In the case of the outlet flap 14, opposite the drive side, the bearing shaft of the outlet flap 14 is a hollow shaft 53 and is integrated directly on the flap, with an opening 52 at the top. When the outlet flap 14 is closed, the cleaning water and any residual water can then be discharged through the hollow shaft, which merges into a container emptying connection 51 . During normal operation of the wetting device, the outlet flap 14 is always open; the outlet flap is only closed for the purpose of cleaning. When the outlet flap 14 is open, the entrance of the hollow shaft is protected by a small overhang of the tube, so that no wet grain kernels can get in from the downflow.

In addition to the accumulation control and the design of the outlet flap, the embodiment of Figures 8 and 9 has the following differences/special features compared to the embodiment of Figures 1-6, which are independent of one another and independently of the accumulation control and the design of the outlet flap, i.e. each individually or can be realized in combination or in sub-combinations:

• The container upper part 2 is in two parts and is composed in the example shown of a first part 111 tapering upwards and a second part 112 designed as a cylindrical intermediate piece.

• There are internal threads in the lower flange ring 5, which is why there are further nozzle rings 114 between the upper flange ring 4 and the lower flange ring 5

- In the example shown there are two nozzle rings 114 - can be clamped. The lower flange ring 5 is firmly connected to the lower part 3 of the container.

• Instead of the manual operating lever, the inlet flap 13 and the outlet flap 14 each have a pneumatic drive 115 and 116, respectively. That too

Provision of a pneumatic drive only for the inlet flap or only for the outlet flap or the provision of an electromechanical drive for the inlet flap and/or outlet flap would be an option; the inlet flap in particular can also be set up to control a flow rate (this option also exists for the outlet flap in particular if there is no separate backwater control flap, ie the outlet flap can then be a regulating flap for regulating an optional accumulation function).

• The central baffle 21 is supported by three horizontal support struts 131 fixed to the container base 3 and a vertical support 132 supported. One of the horizontal support struts 131 is as

Tube formed through which the liquid reaches the inner nozzles 36. The inner impact element 21 with its holder is also shown in FIG.

• The inner nozzles 36 and the outer nozzles 37 in the first outer nozzle ring (in the lower flange ring 5) are always simultaneously supplied with liquid for the wetting application through a flexible or rigid connection. The liquid can, for example, pass through the first outer nozzle ring directly into the horizontal support strut designed as a tube. · The vertical position of the inner nozzles 36 is just below the

(lowermost) outer nozzles 37 approximately at the level of the transition between the lower flange ring 5 and the rest of the container base 3.

• Instead of the upper cleaning lances 41 there are permanently installed cleaning spray balls 141 which protrude slightly above the outer impact elements 23 into the interior of the container. The functioning of the lower cleaning lances 42, however, corresponds to that of the embodiment of Figures 1-6, ie during cleaning water is introduced under pressure into the cleaning spray balls 141 and the cleaning lances 42, whereupon the nozzles of the cleaning spray balls 141 remain in a fixed position and the nozzle elements of the cleaning lances extend . The following applies to all embodiments: In the wetting device, the inner nozzles 36 and/or the outer nozzles 37 can be adapted to the product in terms of jet type and water throughput. In the simplest case, all the outer nozzles are identical. The range of application of the nozzles is optimized for a specific pressure range, eg 3 bar - 10 bar. The water throughput is precisely specified in this pressure range. If more water throughput is required for the wetting process than via the permanently installed nozzles (in the examples shown, the inner nozzles 36 and the outer nozzles 37 in the lower part of the container 3), the area for the water throughput can be equipped with one or more additional nozzle rings 114 as shown in figures 8 and 9 can be enlarged. The maximum number of additional nozzle rings is not limited. The additional nozzle rings 114 can be separately supplied with liquid externally. In the figures 8 and 9, the structure of the additional nozzle rings is shown identically.

Claims

PATENT CLAIMS

1. Wetting device (1) for cereal grains, having a container with a container inlet (11) and a container outlet (12), which are arranged in such a way that grain grains flowing into the container inlet reach the container outlet due to the effect of gravity, the wetting device having a plurality of nozzles (36, 37) in order to wet the grain kernels inside the container, characterized by a flow directing device inside the container, by which a flow of the grain kernels flowing into the container inlet and falling downwards is formed, the nozzles (36 , 37) are arranged such that liquid and/or vapor escaping through them impinges on the kernels below the flow deflector while the kernels are in free fall.

2. Wetting device according to claim 1, wherein the flow deflection device has a central impact element (21) which is hit by grain grains flowing in through the container inlet (11) and which deflects these grain grains outwards.

3. Wetting device according to claim 1 or 2, wherein the flow guide device has a plurality of outer impact elements (23) by which the flow of grain kernels falling downwards from the flow guide device is segmented at least in regions.

4. Wetting device according to claim 3, wherein the outer impact elements (23) are arranged rising towards the outside.

5. Wetting apparatus according to any one of the preceding claims, wherein the flow directing means defines a flow area having a central annulus and jets extending radially outwardly therefrom.

6. Wetting device according to one of the preceding claims, wherein the nozzles include inner nozzles (36) with a spray direction from the inside to the outside and outer nozzles (37) with a spray direction from the outside to the inside.

7. Wetting device according to claim 6, wherein the inner nozzles (36) on a holder of a central impact element (21) and / or the outer

Nozzles (37) are arranged along the circumference of a partially circular-cylindrical container wall of the container.

8 Wetting device according to one of the preceding claims, wherein at least some of the nozzles (36, 37) are designed as fan jet nozzles.

9. Wetting device according to any one of the preceding claims, in which the container is free of internal horizontal surfaces below the container inlet (11) on which grain kernels could rest.

10. A wetting device as claimed in any one of the preceding claims which is free of elements which move during normal use.

11. Wetting device according to one of the preceding claims, comprising a plurality of cleaning nozzles through which a cleaning liquid can be introduced into the container in order to rinse off surfaces of the container wall and of the flow guide device.

12. Wetting device according to claim 11, comprising a plurality of

Cleaning spray balls (141) and/or a plurality of cleaning lances (41, 42) with a nozzle element that can be extended into the interior of the container, each with at least one of the cleaning nozzles.

The wetting apparatus of claim 11 or 12, wherein the cleaning nozzles include upper cleaning nozzles located above the flow director and lower cleaning nozzles located below the flow director.

14. Wetting device according to one of the preceding claims, comprising an arranged below the flow directing device Aufstau control device, through which a flow of

Grain can be regulated through the container outlet (12).

15. Wetting device according to claim 14, having at least one level sensor (75), by means of which the reaching of a level of grain grain level above the accumulation control device can be determined, for regulating a flow rate through the accumulation control device.

16. Wetting device according to claim 14 or 15, wherein the accumulation control device is an accumulation control flap (72) with at least two flap wings (73).

17. Wetting device according to one of the preceding claims, characterized by an outlet flap (14) with a hollow shaft (53) which is connected to at least one opening (52) which is open towards the interior of the container when the outlet flap (14) is in a closed state When the outlet flap (14) is closed, cleaning liquid can be discharged from the interior of the container through the opening (52) and the hollow shaft (53) without it flowing through the container outlet (12).

18. Mill system, having a wetting device (1) according to any one of the preceding claims and a stalling cell (101), wherein the stalling cell (101) is arranged such that the cereal grains from the outlet (12) of the wetting device (1) directly into the stalling cell ( 101) without intervening mechanical processing means.

19. Mill installation according to claim 18, further comprising a grinding unit arranged downstream of the standing cell, in particular with a roller mill and screening devices.

20. Wetting device according to one of Claims 1-17 or mill installation according to one of Claims 18-19, comprising a controller for dosing the liquid as a function of a measured moisture content of the grain kernels.

21. Method for operating a wetting device for grain kernels, in particular according to one of the preceding claims, wherein the wetting device has a container, and the grain kernels that flow in via a container inlet (11) reach the container outlet due to the effect of gravity, characterized in that the Grains are sprayed with a liquid and/or with steam while falling.

22. The method according to claim 21, wherein a contoured falling stream of grain kernels is created in the container and the grain kernels fall down in this contoured falling stream while being sprayed with the liquid or the vapor.

23. The method according to claim 21 or 22, wherein an amount of the liquid or the vapor is regulated so that the mass represents between 0.5% and 12% of a mass of the sprayed grain kernels.