(19)
(11)EP 0 029 942 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
15.06.1988 Bulletin 1988/24

(21)Application number: 80106986.5

(22)Date of filing:  12.11.1980
(51)International Patent Classification (IPC)4A01F 25/16, B65G 65/30

(54)

Universal blending silo and method

Universal-Mischsilo und Verfahren

Procédé et silo mélangeur universel


(84)Designated Contracting States:
AT BE CH DE FR GB IT LI LU NL SE

(30)Priority: 30.11.1979 US 99038

(43)Date of publication of application:
10.06.1981 Bulletin 1981/23

(73)Proprietor: Peschl, Ivan A.S.Z.
NL-6029 RE Sterksel (NL)

(72)Inventor:
  • Peschl, Ivan A.S.Z.
    NL-6029 RE Sterksel (NL)

(74)Representative: Staeger, Sigurd et al
Patentanwälte Dipl.-Ing. S. Staeger Dipl.-Ing. Dipl.- Wirtsch.-Ing. R. Sperling Müllerstrasse 31
D-80469 München
D-80469 München (DE)


(56)References cited: : 
AT-B- 319 852
DE-C- 457 041
GB-A- 842 477
DE-B- 1 277 143
DE-U- 1 889 382
US-A- 2 805 802
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description


    [0001] Prior art blending systems and methods known to the applicant are not truly universal in that they do not readily accommodate different size particles and different composition materials in an efficient manner and, thus, require inefficient multiple recyclings of the materials being blended to achieve a proper blending mixture. This is inefficient both in terms of cost and in terms of time and, moreover, is an inefficient use of energy whose loss may be considerable depending on the size of the silo involved and the quantity of material to be mixed. As will be explained hereinafter, the universal blending silo of the present invention overcomes these disadvantages and is capable of handling a large variety of materials ranging from free flowing to very cohesive; is capable of blending layered as well as column segregated materials; does not impose any meaningful limitations on the height or diameter of the silo to be employed; enables the silo to be adjusted to meet a large range of blending requirements; enables adjustment of the vertical velocity profile over the cross-section of the silo which enhances the blending; and substantially reduces the number of recycle blending .runs which, in some instances, can be reduced to less than one.

    [0002] In the British patent specification 842 477 there is disclosed an improvement in or relating to the devices for the discharge of grain or similar small sized material. So in this reference there is disclosed a device for a silo having a vibrator-frame including a framework of horizontal base which has spaces to form discharge slots there between for the material.

    [0003] Furthermore there are dispersion shelves or flanges positioned below respective said discharge slots, said shelves being adapted to receive material from said slots and to retain the material on said shelves or flanges during non vibration but to discharge the material through said slots consequent upon vibration of the frame.

    [0004] However, this device is not able to carry out a blending procedure but only a discharging of the silo content. Furthermore, when the vibrating frame is working the discharge occurs over the whole section of the silo area, so that it is not possible to discharge one column only.

    Summary of the invention



    [0005] The present invention is an universal blending device and method for blending at least two types of material contained in a silo comprising an input area and a discharge area and a collection area, by layer blending or across vertical columns, column blending, or a combination of layer and column blending.

    [0006] The presently preferred method of the present invention employs either vertical displacement of a partial vertical column of the silo content to provide a representative mixture in every horizontal cross-section in order to reduce the number of necessary recycles to a minimum or substantially simultaneous multilevel displacement, with subsequent uniform discharge over the whole horizontal cross-section of the silo to remix material that may have been segregated during the filling or recycling. In either event, the presently preferred universal blending device includes a blending bottom whose construction gives the opportunity to make a choice of (1) discharge over only a partial area of the outlet area; (2) uniform discharge over the whole outlet area; or (3) predictable discharge velocity distribution over the outlet area.

    [0007] One aspect of the present invention relates to a blending method employing vertical displacement of one or more predetermined partial vertical columns of the silo content, consisting of a number of layers of different or slightly different material, to provide the representative mixture in every horizontal cross-section prior to uniform discharge over the whole outlet area. In this regard, the presently preferred blending method comprises lowering of a partial vertical column of the silo content of the initial upper level into the initial lower level and simultaneously replacing an equal amount of material from the lower level. Using the effect of core-flow or pipe-flow characteristics the partial column of material is lowered without substantially disturbing the adjacent material around the displaced partial column. Lowering of the partial vertical column and recycling of the material to the upper section is continued until a checkered pattern is obtained in a vertical cross-section, and the average composition of the material at each horizontal cross-section is representative of the composition of the entire silo content. Through the above mentioned effect of core-flow, the material which is moved by a recycling installation from the initial lower section will occupy the vacated space in the initial upper section directly above the vertical column.

    [0008] For a simple layer pattern the first blending step is the displacement of the partial vertical column and simultaneously recycling in the upper section. This step will continue until a checkered pattern is obtained in a vertical cross-section and the average composition of the material of each horizontal cross-section is representative of the composition of the entire silo content. However, in different places in a cross-section of the silo, as following a checkered pattern, there are materials of different qualities. A final homogenization is achieved in the collection hopper during the discharge operation where discrete quantities of the material, discharged from different radial positions of the blending bottom and having different qualities, fall over each other during the sliding of the inclined walls of the collection hopper in the direction of the hopper outlet where the material from all areas of the collection hopper will be collected. This precedure enables blending to occur with a number of recycles less than one. For two layer blending the absolute minimum of recycling of 1/4 of the silo content is sufficient to reach a blending with the method of the present invention. For more complicated multilayered silo content, a combination of the displacement of one or more vertical columns with subsequent recirculation with a predicted velocity distribution over the horizontal cross-area of the silo is recommended, in accordance with the present invention, to reach, according to a given composition of layers, an absolute minimum of necessary recycles.

    [0009] The aforementioned step of displacing of one or more vertical columns is used as a pre-blending with subsequent recyclings for final blending of the silo content. In accordance with the present invention, the necessary number of recycles will be a minimum if the velocity distribution over the cross-area of the silo is chosen according to the given pattern with the chosen velocity distribution being reached by adjusting different rates of discharge on different areas of the blending bottom. The third step is the discharge of the blended material. There we have two opportunities. In the case of the material segregating, an adjustment of the blending bottom for uniform velocity distribution is necessary to reach the remixing of segregated components as was previously described with respect to the discharge operation of the checkered pattern. In the case of the material not segregating, the non-uniform velocity distribution which is used for recycling can be used for this discharge operation also. Using this preferred blending procedure the number of recycles can be reduced to less than two. For extremely complicated blending prop- oerties and in extremely high silos, blending ducts with inlet ports at various heights may help maintain the introduced velocity profile by the blending bottom and accelerate the blending process by multilevel discharge of the material from the various layers.

    [0010] It should be noted that for some compositions of layers the minimum number of necessary recycles may be reached by using the optimal velocity distribution during the recycling without displacment of the partial vertical columns. It should also be noted that a blending silo can have more than one blending bottom and more than one partial vertical column can be simultaneously recycled where the blending of this partial column has already occurred. The discharge or displacement of the partial vertical column is achieved by simultaneously discharging, recycling and replacing the material into the vacated area of the vertically displaced partial column. After achieving the checkered pattern in vertical and horizontal cross-section, meaning that a representative mixture is reached within the horizontal cross-section, final homogenization of the checkered pattern of the horizontal cross-section will be achieved through uniform discharge across the whole outlet area in the collection hopper.

    Brief description of drawings



    [0011] 

    Fig. 1A is a partial schematic sectional view of the interior of a universal blending silo in accordance with the present invention;

    Fig. 1 B is a cross-sectional view taken along line B-B in Fig. 1A;

    Fig. 2A is a partial schematic sectional view similar to Fig. 1A of the interior of an alternative emodiment of the universal blending silo of Fig. 1A;

    Fig. 2B is a cross-sectional view similar to Fig. 1B taken along line B-B in Fig. 2A;

    Fig. 3 is a fragmentary enlarged schematic sectional view of a portion of the blending bottom of the silo of Figs. 1A and 2A illustrating a hinged connector;

    Fig. 4 is a diagrammatic illustration of typical examples of velocity profiles in accordance with the present invention;

    Figs. 5A and 5B are diagrammatic illustrations illustrative of the presently preferred method of the present invention illustrating the natural angle of repose in Fig. 5A at which material flow is stopped and illustrating bridging in Fig. 5B at which material flow is stopped;

    Fig. 6 is a diagrammatic illustration of the vibratory effect for discharging material in accordance with the method of the present invention;

    Fig. 7 is a partial schematic sectional view similar to Fig. 1A of another alternative embodiment of the blending bottom in accordance with the present invention;

    Fig. 8 is a partial schematic sectional view similar to Fig. 7 of still another alternative embodiment of the blending bottom portion of the present invention;

    Fig. 9 is a partial schematic sectional view similar to Fig. 7 of yet another alternative embodiment of the blending bottom portion of the universal blending silo of the present invention;

    Fig. 10 is partial schematic sectional view similar to Fig. 7 of still another alternative embodiment of the blending bottom portion of the universal blending silo of the present invention;

    Fig. 11 is a partial schematic sectional view similar to Fig. 7 of yet another alternative embodiment of the blending bottom portion of the universal blending silo of the present invention;

    Fig. 12 is a partial schematic section view similar to Fig. 7 of still another alternative emobodiment of the blending bottom portion of the universal blending silo of the present invention;

    Fig 13 is a partial schematic sectional view similar to Fig. 7 of yet another alternative embodiment of the blending bottom portion of the universal blending silo of the present invention;

    Fig. 14A and 14B are diagrammatic illustrations similar to Fig 5A illustrating the method of disturbing the natural angle of repose of the material in accordance with the method of the present invention;

    Figs. 15A-15D are diagrammatic illustrations representative of the possible directions of oscillating movement of the blending ring in accordance with the method of the present invention;

    Figs. 16A and 16B are diagrammatic illustrations of a blending procedure in accordance with the method of the present invention;

    Figs. 17A-17D are diagrammatic illustrations representative of another blending procedure in accordance with the method of the present invention;

    Figs. 18A-18D are diagrammatic illustrations of another blending procedure in accordance with the method of the present invention;

    Figs. 19A and 19B are diagrammatic illustrations of still another blending procedure in accordance with the method of the present invention; and

    Fig. 20 is a diagrammatic illustration of yet another blending procedure in accordance with the method of the present invention.


    Detailed description of preferred embodiments



    [0012] Referring now to the drawings in detail, and initially to Figs 1 and 2 thereof, the presently preferred overall design of the universal blending silo 200, 200' of the present invention is illustrated in Figs. 1A and 1B with respect to blending silo 200 and in Figs. 2A and 2B with respect to blending silo 200'. As will be described in greater detail hereinafter, universal blending silo 200' is useable in accordance with the method illustrated in Fig. 20 as well as with the method illustrated in Figs. 16-19. As shown and preferred in Figs. 1A and 2A the universal blending silo 200, 200' preferably includes the silo container itself 202, 202', respectively, blending channels with inlet ports along the silo wall, such as blending ducts 43 illustrated in Fig. 2A having inlets 42, a blending bottom 204, 204', a collection hopper 2, 2', and conventional equipment for recycling (not shown) including recycling duct 206, 206'. The blending bottom 204, 204', preferably connected at the bottom of the silo, preferably comprises a plurality of concentric rings 5, 5' of decreasing diameter that are attached to a support frame 4, 4' by means of hinged connectors 10, 10' illustrated in greater detail in Fig. 3. As shown and preferred in Fig. 3, the vertical distance between adjacent pairs of blending rings 5 can be varied by means of adjustable bolts 11'. As also shown and preferred in Fig. 3 a conventional vibrator 7, such as anelectromagnetic or unbalanced vibrator, which can be mounted outside or inside the collection hopper 2, is connected to the blending ring 5 by means of a support. The vibrator 7 preferably transmits the oscillating movement into the blending ring 5 that in turn moves the granular or powdery material above it with centrifugal forces such as diagrammatically illustrated in Fig. 6, in a radial direction towards the interior wall of the collection hopper 2 in accordance with the resultant transport velocity which is dependent on the expression mrro2, where m represents the mass of the particle, r represents the amplitude of oscillation and w represents the frequency of the vibrator 7.

    [0013] As is further shown and preferred in Fig. 3 as well as in Figs. 1A and 2A, a slot or opening is provided between a pair of adjacent rings 5 with the discharge rate which is controlled being, in effect, the discharge rate through the slot between the rings 5. As shown and preferred in Figs. 5A and 5B and further shown in Figs. 14A and 14B, the flow of material is stopped either by the natural angle of repose of the material for large particles or by bridging (Fig 5B) of the material for finer particles, with this bridging or natural angle of repose of the material being disturbed by vibration due to the vibrator which leads to a predictable rate of flow of material such as illustrated in Fig. 14B by adjustment of the amplitude or frequency of the vibrator.

    [0014] Thus, the discharge rate through the slot between adjacent rings 5 is controlled on one hand by adjusting the distance between the rings 5 and on the other hand by the amplitude and frequency of the vibrator 7 as well as also being controlled by utilizing the property of the natural angle of repose of the material being disturbed during vibration, such as illustrated in Fig. 14B. Preferably, the spacing of distance between adjacent rings 5 is such that at their steady state condition which is during shutdown of the vibrators 7, no discharge occurs due to the slot being blocked by the natural angle of repose 17 (Figs. 5A, 14A) of the material or bridging 18 (Fig. 5B) of the material between two adjacent blending rings 5. Thus, by using various combinations of vibrator 7 connections and ring 5 design the discharged rate profile can be varied and selected by the user for optimal blending. In this regard, it should be noted that, preferably, the blending rings 5 may be driven individually by separate vibrators 7, 7' such as illustrated in Figs. 1A and 2A, respectively, or as a rigid assembly of a plurality of blending rings 5 driven by a single common vibrator 7" such as illustrated in Figs. 8-12.

    [0015] Referring now to Figs. 15A-150 as well as Figs. 1A and 2A, the blending bottom 204, 204' preferably comprises the vibrator 7, 7' and blending rings 5, 5' with the vibrator 7, 7' being attached to the blending rings 5, 5' in such a manner so as to move the associated rings 5, 5' in a specified direction. In this regard, the direction of the movement of the blending rings 5, 5' can preferably be controlled by the positioning of the vibrator 7, 7' with respect to the corresponding blending rings 5, 5'. By accomplishing such positioning, various directions of oscillating movement can be achieved such as a translational oscillating movement within the plane of the blending ring 5; a translational oscillating movement perpendicular to the plane of the blending ring 5 such as illustrated in Fig. 15D; a rotational oscillating movement within the plane of the blending ring 5; a rotation oscillating movement perpendicular to the plane of the blending ring 5 such as illustrated in Fig. 15A; or a combination of the aforementioned directions of movement such as illustrated in Figs. 15B and 15C, respectively. It should be noted that the axis of rotational movement or the direction of translational and rotational movement does not necessarily coincide with an axis of symmetry of the blending ring 5.

    [0016] Referring again to Figs. 2A and 2B,these figures illustrate a square universal blending silo configuration as opposed to the cylindrical blending silo configuration illustrated in Figs. 1A and 1 B. As was previously mentioned, in the arrangement shown in Figs. 2A and 2B, blending is carried out by means of a plurality of blending ducts 43 that are preferably mounted along the outside wall of the silo 202', preferably at the corners of polygonal silos such as the square silo 202' of Figs. 2A and 2B. Preferably, the blending ducts 43 have a plurality of inlets 42 located at various heights along the silo wall which permit material to enter into the blending ducts 43 with this material thereafter falling through the blending ducts 43 into the collection hopper 2' thereby bypassing a plurality of layers of different composition and properties. As shown and preferred in Fig. 2A, the entry of material into the blending ducts 43 is controlled by inlet shutters 38 that can preferably be adjusted individually or per channel by means of guide 40 and lever 41. In this manner the number of required recyclings for an acceptable quality of blending can be reduced, as will be explained in greater detail hereinafter with reference to Fig. 20. This, the shutters 38 are preferably opened and closed by means of the central guide 40 with the free space of each inlet 42 preferably being adjusted for each shutter 38 individually by means of adjustment nuts 11, such as illustrated in Fig. 2A. If extreme variations of material properties and composition occur, an acceptable quality of blending may not be achieved in a single run, in which instance the silo content must be recycled. This may be accomplished by means of conventional recycling equipment such as a conventional pheumatic or mechanical conveyor (not shown) which moves the material from the collection hopper 2' through recycling duct 206' and back into the interior of the silo for recycling. Such recycling is preferably accomplished in the same manner in the embodiment of Fig. 1A. The recycling procedure is then preferably repeated' until material achieves an acceptable quality of blending.

    [0017] Before describing the preferred blending procedure or method of the present invention, brief reference shall be made to Figs. 7-13 which illustrate alternative arrangements for the blending bottom 204, 204' portion of the universal blending silo 200, 200' of the present invention. Thus, Fig. 7 illustrates an arrangement characterized by a smaller number of blending rings 5 than in the embodiment of Figs. 1A or 2A with a frustum of a cone 102 preferably being attached between adjacent rings 5 to the conical supporting frame 4 in order to reduce the size of the slot in between the adjacent rings 5. In addition, as will be noted with reference to Fig. 7, the vibrators 7 are preferably positioned beneath the blending rings 5 as opposed to or adjacent to the blending rings as illustrated in Figs. 1A and 2A.

    [0018] Fig. 8 illustrates an alternative embodiment in which the blending rings 5 are all fixedly connected to the conical supporting frame 4" with the supporting frame 4" being hingedly connected to the side walls of the silo by hinge connectors 10". The supporting frame 4" is driven by a common vibrator 7" as opposed to the arrangement illustrated in Figs. 1A and 2A in which the vibrator 7, 7' drives the rings 5, 5' individually.

    [0019] In Fig. 9 an arrangement is illustrated in which a common vibrator 7" drives the collection hopper 2'" with the blending bottom being rigidly connected to the silo via hinge connectors 10'" and with the rings 5 being fixed to the support frame which is in turn fixed to the collection hopper 2"'.

    [0020] In the arrangement illustrated in Fig. 10, the blending rings 5"' are mounted in a common plane with the rings 5"' being mounted on a single frame 4"' which is driven by a common vibrator 7". A circular slot opening is provided between a pair of adjacent rings 5"'.

    [0021] Referring now to Fig. 11, and arrangement is illustrated in which the rings 5 have the form of a frustum of a cone and are mounted on a single frame driven by a common vibrator 7" hingedly connected via connectors 10'" to the silo.

    [0022] Fig. 12 illustrates an arrangement in which the blending bottom is comprised of two levels of rings 5 with the rings in the lower level being positioned under the circular slots between the rings 5 in the upper level and with the frame being driven by a common vibrator 7" and being hingedly connected via hinge connectors 10'" to the silo. The distance between the rings 5 in the upper and lower levels can preferably be adjusted by an adjusting device, such as adjusting nuts 11. Referring now to Fig. 13, the arrangement illustrated therein shows a blending bottom having a conical support frame 400 having its top or apex pointed upwards in the direction against the normal flow of material from the silo. The blending rings 5 are hingedly connected to the conical support frame 400 by means of hinge connectors 10 with the blending rings 5 being individually driven by vibrators 7. In addition, preferably the uppermost blending rings 5 have smaller diameter than the lower blendings rings 5. Thus, in the arrangement illustrated in Fig. 13, discharge of the material takes place due to the fact that the natural angle of repose of the material is disturbed or decreased during vibrations, such as illustrated in Figs. 14A and 14B.

    [0023] Now describing the preferred blending method or procedure of the present invention. It should be noted that the choice of blending silo configuration depends upon the distribution of material properties within the silo. Thus, if material is fed into the silo in discrete batches then layering may occur. In such an instance, each layer may have a different composition or different properties that should be leveled by blending in a procedure which is called layer blending. Alternatively, the particle size distribution of the granular material may be such that segregation occurs during filling or recycling with the coarser components of the material moving toward the silo walls. In such an instance, cylindrical segments of different composition and properties develop and are eventually leveled by blending in a procedure termed segment blending. In addition, combinations of layer and segment blending may be desired such as illustrated in Figs. 18A-18D. Thus, segregation and layering and the number of different components are determining factors in selection of the desired blending procedure to be employed in accordance with the method of the present invention.

    [0024] Referring initially to Figs. 16A and 16B, segment blending of a multi-component system is illustrated with A and B representing materials of different characteristics such as composition and/ or properties. In such an instance, adequate blending may be achieved by only using the blending bottom configuration of the present invention and adjusting it in such a manner that a uniform vertical velocity is reached over the entire cross-section of the silo as diagrammatically illustrated in Fig. 16B.

    [0025] Referring now to Figs. 17A-17D, layer blending of a two layer system comprising layers A, B with each layer having a different composition and/or different properties is shown. In accordance with the method of the present invention, by activating a.plurality of centrally located blending rings 5 a partial vertical column of material above the activated part of the blending bottom whose cross-sectional area is less than the interior cross-sectional area of the silo is lowered or displaced over a vertical distance of the thickness of one layer as illustrated in Figs. 17B and 17C. In order to obtain the checkered blending pattern illustrated in Fig. 17D, a quantity of material must be initially moved from the lower section, layer A in the example of Figs. 17A-17D, into the upper section, layer B in the example of Figs. 17A-17D. This is accomplished in accordance with the method of the present invention by dischaging the partial vertical column of material of the lower section as illustraed in Fig. 17B without substantially disturbing a vertically adjacent partial vertical column of material, and, thereafter, recycling the discharged portion of the partial vertical column of material back into the empty space that has developed in the upper section as a result of this area being vacated by the vertically displaced partial vertical column upper section as illustrated in Figs. 17B and 17C. Thus, the initial lower section of this partial vertical column is discharged into the collection hopper and recycled to occupy the space vacated by the vertically displaced initial upper section. The batch is then alternated across the diameter of the silo and represents in each cross-section of the silo the required ratio of blending with a representative mixture thus being provided in every cross-section. This representative mixture is illustrated by Fig. 17C. This representative mixture is then uniformly discharged across the entire cross-sectional area of the silo as illustrated in Fig. 17D in the same manner as illustrated in Fig. 16B.

    [0026] Referring now to Figs. 18A-18D, the blending system of the present invention can also be used for a combination of layer and segment blending in accordance with the method of the present invention. Thus, as previously mentioned, A and B represent layers of different composition. However, in the example of Figs. 18A-18D, each layer preferably consists of segregated zones of different particle sizes which have been marked by the representative numerals 1 and 2 after the corresponding layer designation A or B to indicate a differentiation in particle size. The aforementioned checkered blending pattern which was achieved in the example of Figs. 17A-17D is again obtained in the example of Figs 18A-18D, however, it is obtained through two recycling steps as opposed to the one recycling step illustrated in the example of Figs. 17A-17D. In the first step illustrated in Figs. 18A and 18B, the central column which is represented in Fig. 18A by layers A2 and B2, is recycled in a manner previously described with reference to Figs. 17A-17D that is a partial vertical column having an initial lower section and an initial upper section is discharged with the lower section being discharged into the collection hopper and recycled to occupy the space vacated by the vertically displaced upper section. The results of this first recycling are diagrammatically illustrated in Fig. 18B. The second recycling step is illustrated in Fig. 18C and preferably occurs solely with respect to the outer vertical column adjacently flanking the central column and is represented by layers A1 and B1. Thus, as was previously described with respect to Figs. 18B and 17A-17C, a partial vertical column in each of the outer columns, having a cross-sectional area less than the interior cross-sectional area of the silo is discharged with the lower section being discharged into the collection hopper and recycled to occupy the space vacated by the vertically displaced upper section in each of the outer columns, such as diagrammatically illustrated in Fig. 18C. Again, a representative mixture in every cross-section is provided and this representative mixture is preferably uniformly discharged over the entire interior cross-sectional area of the silo as illustrated in Fig. 18D.

    [0027] Referring now to Figs. 19A and 19B, layer blending of a multi-component system in accordance with a preferred method of the present invention is illustrated. It should be noted that layer blending of multi-component systems in the prior art normally requires a large number of recycling steps. However, by forcing the sinking velocity of the discharge material in the silo into an appropriate velocity profile in accordance with the present invention, such as by adjustment of the discharge rate of the blending rings 5, the relative position of the layers will shift causing an initial blending. Such a typical velocity profile is illustrated in Fig. 19B by way of example, illustrating examples of possible velocity distribution for recycling. If desired, prior to accomplishing this step the blending procedure previously described with reference to Figs. 17A-17D can be accomplished to accelerate the blending process by initially providing a representative mixture in every cross-section.

    [0028] Referring now to Fig. 20, as well as to Figs. 2A and 2B, layer blending of a multi-component system in accordance with a method of the present invention is illustrated. Thus, in order to reduce the number of recyclings required to accomplish the requisite layer blending, preferably the various layers A-D in the example of Fig. 20, are substantially simultaneously independently discharged into the collection hopper 2' by discharge of these various layers through the blending ducts 43 with the inlets 42 to the blending ducts 43 being disposed at appropriate vertical locations therein adjacent to the respective layers A-D as diagrammatically illustrated in Fig. 20. In addition, the layered material is also preferably simultaneously collectively discharged into the collection hopper 2' through the blending bottom 204' via blending rings 5' and vibrators 7'. The discharged material coming from the blending ducts 43 and from the blending bottom 204' is prefereably collected in the collection hopper 2' and is recycled via recycling duct 206'. Subsequent discharge and recycling is preferably continued until an adequate blending has been obtained. This procedure is preferably useful for tall blending silos, that is silos which are relatively high in comparison to the diameter of the silo.

    [0029] It should be noted that in place of the arrangement illustrated in Fig. 7 in which the frustum of a cone 102 is attached between adjacent rings 5 to the conical supporting frame 4, conical portion 102 could be attached directly to the ring 5, with this arrangement being hingedly connected to the supporting frame 4 in order to reduce the size of the slot in between the adjacent rings 5.

    [0030] It should also be noted that in the instance of free flowing materials, vertically spaced rings 5 should preferably overlap in the direction of material flow between adjacent pairs of rings 5, such as illustrated in Figs. 5A and 5B and Figs. 14A and 14B. However, if cohesive materials are being blended, then the vertically spaced adjacent rings 5 do not need to be overlapped.

    [0031] Thus, by utilizing the preferred method and system of the present invention, universal blending in a common silo may be efficiently obtained wherein a common blending silo may handle blending for all size particles from fine to coarse with a minimal amount of recycling.

    [0032] As used throughout the specification and claims, the term "discharging of the partial vertical column" is meant to refer to its displacement.


    Claims

    1. Universal method for blending at least two types of material contained in a silo to a desired material composition, said silo having one chamber comprising an input area and a dischage area and a collection area, characterized in that the at least two different types of material to be blended are arranged in distninctive columns, such that the pattern of material in a cross-section all over these columns represents a predetermined blending mixture, which cross-section extends substantially perpendicularly to the direction of movement during discharge, and that the pattern of material is discharged all over said cross-section with a predetemined velocity profile to achieve the desired material composition.
     
    2. A method according to claim 1, characterized in that the arranging of the at least two types of material to said distinctive columns comprises the following steps:
     
    selectively and partially discharging the lower section of one or more of the distinctive vertical columns with a predetermined velocity profile into said collection area, simultaneously recycling the discharged material to the top of the silo contents to the place of said discharged columns, respectively,
     
    whereby a desired pattern of the material in the silo is provided by the sinking down of the layer parts in each of said columns.
     
    3. A method according to claim 1 or 2, characterized in the step of providing two or more layers of different composition material as said initial material contents by discharging a desired intermediate pattern and recycling said discharged material.
     
    4. A method according to claim 1, wherein the different types of material are initially contained in the silo in the form of a layer arrangement and the discharging procedure is proceded by a recycling procedure, whereby partial vertical columns over said entire cross-sectional area are simultaneously discharged with a predetermined velocity profile and simultaneously recycled to the top of the silo content as a layer, whereby a desired pattern of material in the silo is provided.
     
    5. A method in accordance with claim 2,3, or 4, further comprising the step that the discharge of said desired pattern of material into said collection area is carried out simultaneously.
     
    6. A method in accordance with claim 1 or 4, further comprising the step that the discharge of said desired pattern of material into said collection area is arranged uniformly over substantially said entire cross-sectional area.
     
    7. A method according to at least one of the claims 1 to 6, characterized in that the method steps according to the aforegoing claims are repeated until a desired blending quality of the mixture is achieved.
     
    8. A universal blending device for blending different material contents of a silo (200, 200') said silo having interior side walls and a blending bottom (204, 204') being operable by means of vibrator means (7, 7') and being connected to a support frame (4, 4', 4") being fixed and connected to said silo side walls, said blending bottom being placed above a collection hopper (2, 2') characterized in that said blending bottom (204, 204') comprises a plurality of spaced apart blending rings (5, 5') hingedly connected to said frame and being positioned adjacent each other in an array above said collection hopper (2) and a circular slot being formed between adjacent pair of rings in the array for enabling controllable flow of material between the adjacent rings into the collection hopper, said blending rings being vib- ratable at a predetermined amplitude and frequency for disturbing the steady state condition of the material between an adjacent pair of rings for providing the controllable flow, and that the vibratory movement of each of the rings has an oscillating-rotating component around the symmetric axis of the rings.
     
    9. A blending device according to claim 8, characterized in that the blending rings (5, 5', 5"') are arranged concentrically.
     
    10. A blending device according to claim 8 or 9, characterized in that the rings of an adjacent pair of rings (5, 5') are positioned above each other in said arrangement.
     
    11. A blending device in accordance with one of the claims 8-10, characterized in that the ring diameter of the upper ring of an adjacent pair of rings is larger than the diameter of the lower ring diameter.
     
    12. A blending device in accordance with one of the claims 8-10 characterized in that the diameter of the lower ring of an adjacent pair of rings is larger than the diameter of the upper ring.
     
    13. A blending device in accordance with one of the claims 8-12, characterized in that said rings (5, 5') are circular.
     
    14. A blending device in accordance with one of the claims 8-12, characterized in that said rings (5, 5') are rectangular.
     
    . 15. A blending device in accordance with one of the claims 8-12, characterized in that said rings (5, 5') are polygonal.
     
    16. A blending device in accordance with one of the claims 8-12, characterized in that the form of said rings (5, 5') is elliptic.
     
    17. A blending device in accordance with one of the claims 8-12, characterized in that the form of said rings (5, 5') is convoluted in the cross-section.
     
    18. A blending device in accordance with at least one of the claims 8-17, characterized in that between said rings (5, 5') is attached a frustrum of a cone (102) for reducing said slot (Fig. 7).
     
    19. A blending device in accordance with at least one of the claims 8-18, characterized in that the inner part of each of said rings overlaps the outer part of the adjacent one, respectively.
     
    20. A blending device in accordance with at least one of the claims 8-19, characterized in that there are provided means (11) for controllable adjusting said spacing between said pair of adjacent rings (5, 5').
     
    21. A blending device in accordance with at least one of the claims 8-20, characterized in that the rings (5, 5') being hingely arranged are connected to a vibrator means (7), respectively.
     
    22. A blending device in accordance with at least one of the claims 8-22, characterized in that said rings are mounted on more than one support frame.
     
    23. A blending device in accordance with at least one of the claims 8-22, characterized in that each of the rings is individually mounted on a support frame.
     
    24. A blending device in accordance with at least one of the claims 8-20, 22 and 23 characterized in that at least one of the support frames (4, 4"') is actuated by a vibrator means (7, 7", 7' ' ').
     
    25. A blending device in accordance with at least one of the claims 8, 9, 13-18, 20-24, wherein said rings (5) are mounted in one plane on a support frame (4) with a slot opening being formed between an adjacent pair of said rings.
     
    26. A blending device in accordance with at least one of the claims 8-24, wherein each of said rings (5) has the form of a frustrum of a cone. (Fig. 11)
     
    27. A blending device in accordance with at least one of the claims 8-26, wherein said silo (200, 200') comprises a plurality of said blending bottoms (204, 204').
     


    Ansprüche

    1. Universalverfahren zum Mischen von mindestens zwei in einem Silo enthaltenen Materialarten zu einer gewünschten Materialkomposition, wobei der Silo eine Kammer mit einem Eingangsbereich, einem Ausgangsbereich und einem Sammelbereich aufweist, dadurch gekennzeichnet, daß die zumindest zwei unterschiedliche miteinander zu vermischende Materialtypen in einzelne Säulen angeordnet werden, so daß das Materialmuster in einem Querschnitt über diese Säulen eine vorbestimmte Mischung darstellt, wobei der Querschnitt spch im wesentlichen senkrecht zur Bewegungsrichtung während der Ausgabe erstreckt, und daß das Materialmuster über den gesamten Querschnitt mit einem vorbestimmten Geschwindigkeitsprofil ausgegeben wird, um die gewünschte Materialkomposition zu erhalten.
     
    2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß das Anordnen der zumindest zwei Materialtypen zu den einzelnen Säulen folgende Schritte umfaßt

    -wahlweises und teilweises Ausgeben des unteren Abschnitts einer oder mehrerer einzelner senkrechter Säulen mpt einem vorbestimmten Geschwindigkeitsprofil in den Sammelbereich,

    -gleichzeitiges Rezirkulieren des ausgegenbenen Materials nach oben zur Spitze des Siloinhalts jeweils zur Stelle der ausgegebenen Säulen,

    -wobei ein gewünschtes Materialmuster im silo durch das Herabsinken der Lagenabschnitte in jeder der Säulen bewirkt wird.


     
    3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß zwei oder mehrere Lagen unterschiedlichen Kompositionsmaterials als Ursprungsmaterialinhalt durch Ausgeben eines gewünschten Zwischenmusters und Rezirkulieren des ausgebenen Materials vorgesehen werden.
     
    4. Verfahren nach Anspruch 1, wobei die unterschiedlichen Materialarten ursprünglich in dem Silo in Form einer Lagenanordnung enthalten sind und die Ausgabeprozedur von einer Rezirkulierungsprozedur gefolgt wird, wobei vertikale Teilsäulen über den gesamten Querschnittsbereich gleichzeitig mit einem vorbestimmten Geschwindigkeitsprofil ausgegeben und gleichzeitig nach oben zur Spitze des Siloinhalts als Lage gefördert werden, wobei ein gewünschtes Materialmuster in dem Silo bereitgestellt wird.
     
    5. Verfahren nach Anspruch 2, 3 oder 4, wobei weiter der Schritt enthalten ist, daß die Ausgabe des gewünschten Materialmusters in den Sammelbereich gleichzeitig durchgeführt wird.
     
    6. Verfahren nach Anspruch 1 oder 4, mit dem weiteren Schritt, daß die Ausgabe des gewünschten Materialmusters in den Sammelbereich gleichförmig über im wesentlichen die gesamte Querschnittsfläche durchgeführt wird.
     
    7. Verfahren nach mindestens einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß die Verfahrensschritte der vorangegangenen Ansprüche wiederholt werden, bid eine gewünschte Mischungsqualität der Mischung erreicht wird.
     
    8. Universal-Mischvorrichtung zum Mischen unterschiedlicher Materialinhalte eines Silos (200, 200'), wobei der Silo innere Seitenwände und einen Mischboden (204, 204'), der mit einem mit den Siloseitenwänden befestigtem Trägerrahmen (4, 4', 4") verbunden und mittels Vibratormitteln (7, 7') betätigbar ist, wobei er über einem Sammeltrichter (2, 2') angeordnet ist, dadurch gekennzeichent, daß der Mischboden (204, 204') eine Vielzahl von einander beabstandeten Mischringen (5, 5') aufweist, die angehängt mit dem Rahmen verbunden und einander benachbart in einer Zusammendordnung oberhalb des Sammeltrichters (2) angeordnet sind, wobei ein kreisförmiger Schlitz zwischen einem Paar benachbarter Ringe in der Anordnung ausgebildet ist, um einen gesteuerten Materialfluß zwischen den benachbarten Ringen in der Sammeltrichter zu ermöglichen, und wobei die Mischringe mit einer vorbestimmten Amplitude und Frequenz zum Stören der Zustandbedingung des Materials zwischen einem benachbarten Paar von Ringen vibreirbar sind, um einen gesteuerten Fluß herbeizuführen, und daß die Vibrationsbewegung jedes Rings eine oszilierende-rotierende Komponente um die Symmetrieachse der Ringe aufweist.
     
    9. Mischvorrichtung nach Anspruch 8, dadurch gekennzeichnet, daß die Mischringe (5, 5', 5"), konzentrisch angeordnet sind.
     
    10. Mischvorrichtung nach Anspruch 8 oder 9, dadurch gekennzeichnet, daß die Ringe eines benachbarten Ringpaares (5, 5') in der Anordnung übereinander positioniert sind.
     
    11. Mischvorrichtung nach mindestens einen der Ansprüche 8-10, dadurch gekennzeichnet, daß der Ringdurchmesser des oberen Rings eines benachbarten Ringpaars größer ist als der Durchmesser des unteren Rings.
     
    12. Mischvorrichtung nach mindestens einem der Ansprüche 8-10, dadurch gekenneichnet, daß der Durchmesser des unteren Rings eines benachbarten Ringpaares größer ist als der Durchmesser des oberen Rings.
     
    13. Mischvorrichtung nach mindestens einem der Ansprüche 8-12, dadurch gekennzeichnet, daß die Ringe (5, 5') kreisförmig sind.
     
    14. Mischvorrichtung nach mindestens einem der Ansprüche 8-12, dadurch gekennzeichnet, daß die Ringe (5, 5') rechtwinkling sind.
     
    15. Mischvorrichtung nach mindestens einem der Ansprüche 8-12, dadurch gekennzeichnet, daß die Ringe (5, 5') polygonal sind.
     
    16. Mischvorrichtung nach mindestens einem der Ansprüche 1-12, dadurch gekennzeichnet, daß die Form der Ringe (5, 5') elliptisch ist.
     
    17. Mischvorrichtung nach mindestens einem der Ansprüche 1-12, dadurch gekennzeichnet, daß die Form der Ringe (5, 5') im Querschnitt gewellt ist.
     
    18. Mischvorrichtung nach mindestens einem der Ansprüche 8-17, dadurch gekennzeichnet, daß zwischen den Ringen (5, 5') ein Kegelstumpf (102) zur Reduzierung des Schlitzes befestigt ist (Fig. 7).
     
    19. Mischvorrichtung nach mindestens einem der Ansprüche 8-18, dadurch gekennzeichent, daß der innere Teil eines jeden der Ringe jeweils den äußeren Teil des benachbarten überlappt.
     
    20. Mischvorrichtung nach mindestens einem der Ansprüche 1-19, dadurch gekennzeichnet, daß Mittel (11) zum gesteuerten Einstellen des Abstands zwischen dem Paar benachbarter Ringe (5, 5') vorgesehen sind.
     
    21. Mischvorrichtung nach mindestens einem der Ansprüche 8-20, dadurch gekennzeichnet, daß die Ringe (5, 5') hängend angeordnet und jeweils mit Vibratormitteln (7) verbunden sind.
     
    22. Mischvorrichtung nach mindestens einem der Ansprüche 8-21, dadurch gekennzeichnet, daß die Ringe an mehr als einem Trägerrahmen befestigt sind.
     
    23. Mischvorrichtung nach mindestens einem der Ansprüche 8-22, dadurch gekennzeichnet, daß jeder Ring individuell an einem Trägerrahmen befestigt ist.
     
    24. Mischvorrichtung nach mindestens einem der Ansprüche 8-20, 22 und 23, dadurch gekennzeichnet, daß zumindest einer der Trägerrahmen (4, 4"') von einem Vibratormittel (7, 7", 7"') aktiviert wird.
     
    25. Mischvorrichtung nach mindestens einem der Ansprüche 8, 9, 13-18, 20-24, wobei die Ringe (5) in einer Ebene auf einem Trägerrahmen (5) einer Schlitzöffnung zwischen einem benachbarten Ringpaar angeordnet sind.
     
    26. Mischvorrichtung nach mindestens einem der Ansprüche 8-24, wobei jeder der Ringe (5) die Form eines Kegelstumpfs (Fig. 11) aufweist.
     
    27. Mischvorrichtung nach zumindest einem der Ansprüche 8-26, wobei der Silo (200, 200') eine Vielzahl von Mischblöden (204, 204') aufweist.
     


    Revendications

    1. Procédé universel de mélange dosé d'au moins deux sortes de matière contenues dans un silo pour l'obtention d'une composition de matière souhaitée, ledit silo présentant une chambre comportant une zone d'entrée et une zone de déchargement et une zone de collecte, caractérisé en ce que les deux ou plusieurs sortes de matière à mélanger sont disposées en colonnes distinctives, de façon que le motif de matière existant dans une section droite passant par la totalité de ces colonnes représente un mélange dosé déterminé, laquelle section droite s'étend quasi perpendiculairement à la direction de mouvement pendant déchargement, et que le motif de matière est déchargé sur toute ladite section droite avec un profil de vitesse déterminé pour l'obtention de la composition de matière souhaitée.
     
    2. Procédé selon la revendication 1, caractérisé en ce que la disposition des deux ou plusieurs sortes de matière en lesdites colonnes distinctives comprend les opérations suivantes: -déchargement sélectif et partiel de la section inférieure d'une ou plusieurs des colonnes verticales distinctives avec un profil de vitesse déterminé jusqu'au sein de ladite zone de collecte, recyclage simultané de la matière déchargée vers le sommet du contenu du silo en remplacement desdites colonnes déchargées, respectivement, -de sorte qu'un motif souhaité de la matière présente dans le silo est établi par la descente des parties de couche de chacune desdites colonnes.
     
    3. Procédé selon la revendication 1 ou 2, charac- térisé par l'opération consistant à prévoir deux ou plusieurs couches .de matière de compositions différentes en tant que sus dits contenus en matière intiaux en déchargeant un motif intermédiaire souhaité et en recyclant ladite matière déchargée.
     
    4. Procédé selon la revendication 1, dans lequel les différentes sortes de matière sont initialement contenues dans le silo sous forme de disposition en couches et le processus de déchargement est poursuivi par un processus de recyclage, de sorte que des colonnes verticales partielles couvrant toute ladite section sont déchargées simultanément avec un profil de vitesse déterminé et simultanément recyclées vers le sommet du contenu du silo sous forme de couche, de sorte qu'un motif souhaité de matière présente dans le silo se trouve établi.
     
    5. Procédé selon la revendication 2, 3 ou 4, comprenant encore l'opération que le déchargement dudit motif souhaité de matière au sein de ladite zone de collecte est opéré simultanément.
     
    6. Procédé selon la revendication 1 ou 4, comprenant encore l'opération que le déchargement dudit motif souhaité de matière au sein de ladite zone de collecte est réparti uniformément sur la quasi-totalité de ladite aire de section.
     
    7. Procédé selon l'une au moins des revendications 1 à 6, caractérisé en ce qu' on répète les opérations de procédé selon les revendications précédentes jusqu'à obtenir une qualité de dosage souhaitée du mélange.
     
    8. Dispositif mélangeur-doseur universel pour le mélange de différents contenus de matière d'un silo (200, 200') ledit silo comportant des parois latérales intérieures et une base de dosage (204, 204') étant manoeuvrable par un moyen vibrateur (7, 7') et étant reliée à un bâti de support (4, 4', 4") fixé et relié aux dites parois latérales de silo, ladite base de dosage étant placée au-dessus d'une trémie de collecte (2, 2') caractérisé en ce que ladite base de dosage (204, 204') comprend une série d'anneaux de dosage espacés les uns des autres (5, 5') articulés sur ledit bâti et placés près les uns des autres en ensemble régulier au-dessus de ladite trémie de collecté (2) et une fente circulaire étant ménagée entre deux anneaux voisins de l'ensemble pour permettre à la matière de s'écouler de manière réglable entre les anneaux voisins jusqu'à l'intérieur de la trémie de collecte, lesdits anneaux de dosage pouvant être mis en vibration à une amplitude et à une fréquence déterminées pour perturber l'état de régime permanent de la matière entre deux anneaux voisions pour établir l'écoulement réglable, et que le mouvement vibratoire de chacun des anneaux présente une composante d'oscillation-rotation autour de l'axe de symétrie des anneaux.
     
    9. Dispositif mélangeur-doseur selon la revendication 8, caractérisé en ce que les anneaux de dosage (5, 5', 5"') sont disposés concentriquement.
     
    10. Dispositif mélangeur-doseur selon la revendication 8 ou 9, caractérisé en ce que les anneaux d'une paire d'anneaux voisins (5, 5') sont placés l'un au-dessus de l'autre dans ladite disposition.
     
    11. Dispositif mélangeur-doseur selon l'une des revendications 8 à 10, caractérisé en ce que le diamètre d'anneau de l'anneau supérieur d'une paire d'anneaux voisins est plus grand que le diamètre de l'anneau inférieur.
     
    12. Dispositif mélangeur-doseur selon l'une quelconque des revendiations 8 à 10, caractérisé en ce que le diamètre de l'anneau inférieur d'une paire d'anneaux voisins est plus grand que le diamètre de l'anneau supérieur.
     
    13. Dispositif mélangeur-doseur selon l'une des revendications 8 à 12, caractérisé en ce que lesdits anneaux (5, 5') sont circulaires.
     
    14. Dispositif mélangeur-doseur selon l'une des revendications 8 à 12, caractérisé en ce que lesdits anneaux (5, 5') sont rectangulaires.
     
    15. Dispositif mélangeur-doseur selon l'une des revendications 8 à 12, caractérisé en ce que lesdits anneaux (5, 5') sont polygonaux.
     
    16. Dispositif mélangeur-doseur selon l'une des revendications 8 à 12, caractérisé en ce que la forme des dits anneaux (5, 5') est elliptique.
     
    17. Dispositif mélangeur-doseur selon l'une quelconque des revendications 8 à 12, caractérisé en ce que la forme desdits anneaux (5, 5') est convolutée en coupe droite.
     
    18. Dispositif mélangeur-doseur selon l'une au moins des revendications 8 à 17, caractérisé en ce qu'entre lesdits anneaux (5, 5') est fixé un tronc de cône (102) de réduction de ladite fente (figure 7).
     
    19. Dispositif mélangeur-doseur selon l'une au moins des revendications 8 à 18, caractérisé en ce que la partie intérieure de chacun desdits anneaux chevauche la partie extérieure de l'anneau respectivement voisin.
     
    20. Dispositif mélangeur-doseur suivant l'une au moins des revendications 8 à 19, caractérisé en ce qu'il est prévu des moyens (11) d'ajustement réglable dudit espacement entre deux anneaux voisins (5, 5').
     
    21. Dispositif mélangeur-doseur selon l'une au moins des revendications 8 à 20, caractérisé en ce que les anneaux (5, 5') articulés sont respectivement reliés à un moyen vibrateur (7).
     
    22. Dispositif mélangeur-doseur selon l'une au moins des revendications 8 à 21, caractérisé en ce que lesdits anneaux sont montés sur plus d'un bâti de support.
     
    23. Dispositif melangeur-doseur selong l'une au moins des revendications 8 à 22, caractérisé en ce que chacun des anneaux est individuellement monté sur un bâti de support.
     
    24. Dispositif mélangeure-doseur selon l'une au moins des revendications 8 à 20, 22 et 23, caractérisé en ce qu'au moins un des bâtis de support (4, 4"') est manoeuvré par un moyen vibrateur (7, 7", 7"').
     
    25. Dispositif mélangeur-doseur selon l'une au moins des revendications 8, 9, 13-18, 20-24, dans lequel lesdits anneaux (5) sont montés dans un plan sur un bâti de support (4), une ouverture en fente étant ménagée entre deux anneaux voisins.
     
    26. Dispositif mélangeur-doseur selon l'une au moins des revendications 8 à 24, dans lequel chacun desdits anneaux (5) a la forme d'un tronc de cône (figure 11).
     
    27. Dispositif mélangeur-doseur selon l'une au moins des revendications 8 à 26, dans lequel ledit silo (200, 200') comprend une série desdites bases de dosage (204, 204').
     




    Drawing