|Title of Invention||
"A WET BRUISING MILL AND METHOD FOR WET MILLING"
|Abstract||A wet bruising mill (1) with a squeezing means (3), an accommodation space (6) arranged underneath the squeezing means (3), and a conveying element (8) for bruised matter following the accommodation space (6), and with a water introduction means (14) in the accommodation space (6), wherein the accommodation space (6) comprises a collection area (12) situated in the flow direction in front of the conveying element (8) which is delimited to the top by al normal level line (11), characterized in that the water introduction means (14) comprises a distributor (16) arranged in the collection area (12) of the accommodation space (6) with a group (17a) of outlets (117) facing upwards for water under pressure.|
|Full Text||The invention relates to a wet bruising mill of the type explained in the preamble of claim 1.
Such a wet bruising mill is known from EP 1 001 015. The known wet bruising mill contains a squeezing means by which previously soaked malt is bruised, wherein the malt contents, i.e. the endosperm, is crushed and pressed out of the husks. The mill contains the common pairs of rollers which are arranged above an accommodation space for the bruised matter. Due to the gravity effect, the bruised matter falls into the accommodation space which narrows like a funnel in the lower part and leads to an outlet which is associated to a conveying means, usually a feed pump. The bruised matter collects in the lower area of the accommodation space and is removed by the conveying means. As is explained in detail in this citation, the removal of the bruised matter causes difficulties as the finely bruised dry endosperm tends to agglomeration of the bruised grain if not enough water is supplied and the matter is not thoroughly mixed, thereby reducing discharge.
Therefore, a water supply means is provided in the known wet bruising mill which introduces water into the accommodation space below the squeezers but above a normal level line monitored by level control and thus improves the pumpability of the mashed bruised matter. The water introduction means contains a nozzle arrangement extending through the wall of the accommodation space with a first and a second nozzle, the first nozzle being designed such that it forms an upper and a lower partial flow. The upper partial flow is spread apart and is directed slightly upwards towards the centre of the accommodation space. This upper partial flow then essentially uniformly falls onto the surface of the collected bruised matter. The lower partial flow is conducted along the wall of the accommodation space and in particular along the wall of its lower funnel-shaped area towards the outlet. It showed, however, that with this technique the problem of clumping and the accompanied bad flow rate can neither be optimally solved, in particular if very thick mashes are used, as they are employed, for example, for high gravity brewing (mixing ratio e.g. 250 kg of water for 100 kg of bruised malt).
It has furthermore already been tried, for example in the DE 42 13 204 or the DE 25 33 555, to introduce water into the bruised matter by distributors which project into the
accommodation space above the normal level line from the side and are directed either to the surface of the collected bruised grain or towards the crushing nip of the squeezers. Here, however, the mentioned problems are neither optimally solved.
The object underlying the invention therefore is to provide a wet bruising mill and a method for its operation which lead to bruised grains that can be pumped in an improved manner.
In a wet bruising mill, the object is achieved by the features of claim 1 and in a method by the features of claim 9.
By the embodiment according to the invention, the water is introduced directly inside the settling bruised grain and can optimally act there. In particular, according to the invention the water is brought into areas of the bruised grain which can not or only incompletely be reached with the water introduction means of the prior art, i.e. into the centre of the bruised mass near the pump. That means, it can not happen that outer layers of the collected bruised grain, for example the upper layer of the settled bruised grain or layers at the wall, macerate and form a barrier against further penetration of water inside the bruised mass.
Advantageous further developments of the invention can be taken from the subclaims.
By a distribution line horizontally projecting into the accommodation space, on the one hand an essentially uniform distribution and deflection of the bruised grain across the cross-section of the accommodation space is achieved; on the other hand, the distribution line only inessentially hinders the free fall of the bruised grain from the crushing means.
Particular attention has to be paid to the arrangement and dimensioning of the outlets of the distributor. Preferably, the distributor is provided with a group of outlets essentially facing upwards and a group of outlets essentially facing downwards, where it is not absolutely necessary for the direction of the outlets to be located on a vertical, but they preferably extend at an angle to the vertical.
Preferably, the outlets facing upwards and downwards have different outlet cross-sections, where the outlets facing upwards can have a smaller outlet cross-section to prevent the penetration of bruised grain.
The effect of an obstacle can be further reduced if the distributor comprises a deflecting cross-section at its upper side facing the squeezers.
Preferably, the distributor has an essentially (right-)angled, in particular square cross-section which is arranged so as to stand on the tip, so that the upper side facing upwards like a roof acts as deflector.
If a plurality of conveying means arranged one next to the other is associated to the accommodation space, the distributor should be preferably arranged symmetrically to the conveying means, as in this manner, only one distributor is necessary which serves both conveying means.
The introduction of water diagonally to the vertical line, i.e. diagonally to the flow direction of the bruised grain in the collecting area, causes an even better distribution of the water in the collected bruised matter.
In the following, one embodiment of the invention is illustrated more in detail with reference to the drawings. In the drawings:
Fig. 1 shows a highly schematized representation of the wet bruising mill according to the invention in a side view,
Fig. 2 shows a highly schematized representation of the wet bruising mill according to the invention in a front view, and
Fig. 3 shows a highly schematized perspective partial representation of the distributor according to the invention.
Fig. 1 shows a highly schematized sectioned partial representation of a wet bruising mill 1, which can be a wet bruising mill of any conventional design, except for the details according to the invention described below. The wet bruising mill 1 contains a housing frame 2 in which a squeezing works 3 is arranged. The squeezing works 3 can be of any conventional design, in the represented embodiment, two squeezers 3a and 3b being provided which are located
horizontally opposite one another thus forming a crushing nip 4 and which are driven in opposite directions about essentially horizontal axles.
A feeder means 5 which can also be of a conventional type is located above the crushing nip 4. If the wet bruising mill according to the invention is used for example for bruising previously soaked malt for beer production, the feeder means 5 can be the outlet of a feed roller of a malt hopper which distributes presoaked malt (or other matter to be bruised) uniformly in the longitudinal direction across the crushing nip 4.
Below the squeezing works 3, the wet bruising mill 1 contains an accommodation space 6 for the bruised matter falling out of the squeezing works 3. The accommodation space 6 is mainly formed by a hopper 6a which can be followed by vertical walls 6b in the direction of the squeezing works 3. The vertical walls 6b and the upper edge of the hopper 6a include a horizontal cross-sectional area extending at least over the dimensions of the crushing nip 4 of the squeezing works 3. In the represented embodiment, this cross-sectional area reaches across the complete extension of the squeezers 3 a, 3b, so that even bruised matter can be collected which first adheres to the squeezers 3a, 3b and only later falls downwards. Possibly, a (non-depicted) stripper can be provided for the squeezers.
The hopper 6a tapers as its distance from the squeezing works 3 increases and ends in at least one outlet 7 at its deepest point. In the embodiment shown in Fig. 2, two outlets 7a and 7b are provided which are situated at a distance one next to the other along the extension of the crushing nip 4 in the same horizontal plane. The hopper 6a can have any desired shape, in the shown embodiment the hopper 6a has a long-stretched out oval to rectangular cross-sectional shape and side walls with different tilts.
A conveying element 8 is associated to each outlet 7, in case of two outlets 7a, 7b, two conveying elements 8a, 8b being provided which preferably have an identical design.
As a conveying element 8, any suited known conveying means can be used, and in particular the pumps usually used for this purpose are employed. In the represented embodiment, a centrifugal pump with a channel impeller or an open impeller is used which pumps into a pump-offline 9 and 9a, 9b, respectively. Above the conveying element 8, in the hopper 6a, an inducer (not shown) can be provided which facilitates and improves the introduction of the
bruised matter into the outlet 7 and the conveying means 8.
The wet bruising mill 1 according to the invention is designed such that the bruised grain exiting from the squeezing works 3 falls into and through the accommodation space 6 under the influence of gravity and collects and accumulates above the outlet from where it can be removed by the conveying element 8 if required. The filling level of the bruised grain in the accommodation space 6 is determined and monitored by a level regulation 10 (Fig. 2). The level regulation 10 contains an apparatus 1 Oa with which a normal level 11 is defined in the accommodation space 6. The means lOa preferably contains a pressure cell with which the normal filling of the accommodation space is determined and monitored. The level regulation 10 can furthermore contain a means lOb which ensures that the filling level in the accommodation space 6 does not exceed a certain level, so that the squeezing works 3 can still work correctly (full message).
The normal level line 11 limits a collection area 12 inside the accommodation space 6 upwards, i.e. in the direction to the squeezing works 3. In the represented embodiment, the normal level line 11 is in the area of the hopper 6a. Preferably, the normal level line 11 is slightly underneath the largest cross-section of the hopper 6a, at the transition to the vertical limits 6b, in particular approximately in the upper third to the upper fourth of the hopper 6a. The level line limiting the collection space 12 should furthermore have a distance to the squeezing works 3 leading to a sufficiently spacious head room 13 in which the bruised grain can unhinderedly fall down from the squeezing works 3 by gravity, so that it does not accumulate in the squeezing works 3.
The wet bruising mill 1 furthermore contains a water introduction means 14 for introducing water under pressure. The water introduction means contains a supply line 15 and a distributor 16 with at least one outlet 17.
The distributor 16 is arranged in the collection space 12, i.e. in the center of the bruised matter accumulating therein. The distributor 16 is situated in the hopper 6a of the accommodation space. The distributor 16 is situated in the proximity of the outlet(s) 7 and in case of several outlets 7a, 7b, symmetrically to them. The distributor 16 is in any case situated at a point where in normal operation (i.e. except during starting and completely emptying of the wet bruising mill 1) it is covered by bruised grain at least in the area of its outlet.
The distributor 16 contains at least one long-stretched out distributor line 16.1, 16.2, 16.3 which essentially horizontally extends from one wall of the hopper 6a towards the opposite wall and which is supplied with water by the water line 15 from one of its front sides 16a, while the opposite front side 16b is closed or else provided with one or several outlets, and ends at or shortly before the wall of the hopper 6a opposite the line opening of the water line 15. In the represented embodiment, three distributor lines 16.1, 16.2, 16.3 are provided which are distributed uniformly in the collection area 12. The central distributor line 16.2 is preferably situated in the center above the two outlets, while the two other ones are situated each laterally and next to the central line of the outlets 7a, 7b.
The distributor line 16.1, 16.2, 16.3 has a (right-)angled or box-shaped cross-section, preferably a square cross-section, but it can also have other cross-sectional shapes and be e.g. rhomboidal, triangular, rounded, circular, oval or drop-shaped. The distributor line 16.1, 16.2, 16.3 is arranged such that it extends diagonally to the crushing nip 4. The distributor line 16.1, 16.2, 16.3 is preferably situated in the collection space 12, such that an edge of the cross-section or another elevation, in the represented embodiment the edge 16c, faces towards the squeezing works 3 and forms the upper side of the distributor line 16.1, 16.2, 16.3. The side faces 16d and 16e following the edge 16c thus form, together with the edge 16c, a deflector 18 which takes care that no bruised grain remains lying on the distributor line 16.1, 16.2, 16.3. In case of a square cross-section, one of the diagonals preferably lies essentially in a horizontal plane and the other diagonal essentially in a vertical plane.
The distributor 16 is provided with a plurality of outlets 17. The outlets 17 face upwards and/or downwards, wherein at least the outlets 17 facing upwards preferably face into one direction including an angle differing by 90° to the vertical. In the represented embodiment, the outlets 17 are distributed across all side walls of the distributor line 16.1, 16.2, 16.3, i.e. across the side walls 16d and 16e facing upwards, i.e. towards the squeezing works 3, as well as the side walls 16f and 16g facing downwards, i.e. towards the conveying element 8. The outlets 17 are preferably arranged in one or several rows on the side walls 16d to 16g, however, they can also be distributed irregularly or in other patterns.
In the represented embodiment, the distributor 16 contains two groups of outlets 17. The first group 17a of the outlets 17 faces upwards and is accordingly provided on the side walls 16d
and 16e facing upwards. The outlets 17 of this group 17a are designed as simple holes with an outlet cross-section which is tuned to the available water pressure (for example the pressure of the common brewing water network), such that a clogging of the outlets of the group 17a by bruised grain or a penetration of the bruised grain into the distributor 16 is prevented. The outlets 17 of the second group 17b face downwards, they are accordingly provided at the side faces 16f, 16g facing downwards. These are designed as nozzles preferably at projections, so that they are able to generate directed water jets. The water jets generated by the group 17b are directed towards the outlet(s) 7, so that even smaller agglomerations can be thereby dissolved. The outflow cross-section of the outlets of group 17b is larger than the outflow cross-section of the outlets of group 17a.
In operation, the matter to be bruised, for example presoaked malt in beer production, is introduced into the squeezing works 3 via the inlet means 5, preferably under the influence of gravity. In the squeezing works 3, the matter is bruised and reaches the accommodation space 6 through the crushing nip 4. There, it falls down again under the influence of gravity and collects in the collection space 12 for being subsequently drawn off by the conveying element or elements 8 until the normal level line 11 is reached. At this point at the latest, but preferably already during the collection, water is introduced via the water introduction line 14. By the arrangement of the distributor 16 inside the collected bruised matter, the same is moistened from the inside, whereby with respect to the prior art essentially more intense moistening of the bruised matter becomes possible, so that conveying problems during the conveyance via the conveying elements, in particular when pumps are used, are no longer to be feared.
One can see from the above explanations that the geometry of the distributor and in particular its cross-section(s) should be adapted to the special construction and geometry of the wet bruising mill. Thus, the outlets 17 of the distributor facing downwards should be preferably directed towards the outlets 7 of the accommodation space 12, which in case of only one single outlet 7 in the accommodation space means that either the nozzle-like projections of the group 17b are diagonally arranged at the side face of the rectangular distributor 16 according to Fig. 3, or that the distributor 3 for example comprises a triangular cross-section with an essentially horizontal lower side face from which the nozzle-like outlets of the second group project. Furthermore, the normal level line can be provided at any arbitrary point in the accommodation space, wherein, however, the distributor 16 is always arranged underneath the
normal level line. It is furthermore practical to arrange the distributor relatively near the outlet or outlets 7 of the accommodation space as this is the point where the risk of agglomerations or bridge formations is highest if the bruised grain is not sufficiently moistened. The water introduction means 14 can furthermore contain additional known water distributors, for example in the form of simple water pockets which let water flow from above the filling level along the hopper walls.
The wet bruising mill according to the invention is especially designed for bruising malt for beer production, however, it can also be used for other bruising tasks. As deflectors, separate components can be employed. Instead of distributor lines, the distributor can for example contain point-like arranged distributor heads or the like.
1. A wet bruising mill (1) with a squeezing means (3), an accommodation space (6)
arranged underneath the squeezing means (3), and a conveying element (8) for
bruised matter following the accommodation space (6), and with a water introduction
means (14) in the accommodation space (6), wherein the accommodation space (6)
comprises a collection area (12) situated in the flow direction in front of the
conveying element (8) which is delimited to the top by al normal level line (11),
characterized in that the water introduction means (14) comprises a distributor (16)
arranged in the collection area (12) of the accommodation space (6) with a group (17a)
of outlets (117) facing upwards for water under pressure.
2. The wet bruising mill as claimed in Claim 1, wherein the distributor (16) comprises at
least one distributor line (16.1, 16.2,16.3) extending substantially horizontally into the
accommodation space (6).
3. The wet bruising mill as claimed in Claim I or 2, wherein the accommodation space
(6) comprises a hopper (6a), in which the distributor (16) is arranged.
4. The wet bruising mill as claimed in one of Claims I to 3, wherein the distributor (16)
is provided with a group (17b) of outlets (17) facing downwards.
5. The wet bruising mill as claimed in Claim 4, wherein the outlets (17a) facing upwards have a smaller outlet cross section than the outlets (17b) facing upwards.
6. The wet bruising mill as claimed in one of Claims 1 to 5, wherein the distributor (16) comprises a deflector (18) on its upper side facing the squeezing means (3).
7. The wet bruising mill as claimed in one of Claims 1 to 6, wherein the distributor (16) comprises a cross section which in which one edge (16c) projects upward and which is preferably substantially square.
8. The wet bruising mill as claimed in one of Claims I to 7, wherein a plurality of
conveying elements (8) arranged one next to one another is associated to the
accommodation space (6), and that the distributor (16) is arranged symmetrically to
the conveying elements, (8)
9. Method for wet milling, wherein matter to be crushed is fed to a squeezing means (3),
and the bruist grain is mixed with water, settles in a collecting area (12) and is
removed by a conveying element (8), wherein the is injected into the inside of the
bruist mass settled in the collection area (12).
10. Method as claimed in Claim 9, wherein the water is injected into the bruist grain at an angle to the vertical.
|Indian Patent Application Number||1427/DEL/2007|
|PG Journal Number||06/2014|
|Date of Filing||05-Jul-2007|
|Name of Patentee||KRONES AG|
|Applicant Address||BOHMERWALDSTRASSE 5 93073 NEUTRAUBLING GERMANY.|
|PCT International Classification Number||B02C|
|PCT International Application Number||N/A|
|PCT International Filing date|