DE2645616A1 - DEVICE AND METHOD FOR MIXING PARTICULAR SUBSTANCES - Google Patents

Description

PATENT LAWYERS

DR.-ING. H. FINCKE DIPL.-ING. H. BOHR DIPL.-ING. S. STAEGER DR. Rer. nat. R. KNEISSL

8 MONKS 5, 8. Mullerslrasse 31 Telephone: (089) '24 6Ό60 Telegrams: Claims Munich Telex: 523903 claim d

Folder 2k 128

Case P 28 254/28 585

IMPERIAL CHEMICAL INDUSTRIES LIMITED

Imperial Chemical House, Millbank,

London, S ^- WIP 3JF, UK

Mixing device and method of particulate matter

The invention relates to apparatus and methods for mixing particulate matter, in particular to an apparatus and method for mixing utilizing a gravity flow of particles.

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When manufacturing a substance, for example a chemical compound, the manufacturing process generally carried out in batches. So a certain amount of a reactant can match a suitable one Be subjected to temperature cycling for a suitable time to establish a connection. at The connection established ends the time cycle removed from the reaction vessel and started making a second batch, etc. With a view to possible slight fluctuations in the quality of the starting material, the time cycle, the temperature and the like two batches are not identical to each other. Depending on the use to which the product is to be put, becomes an acceptable "margin of tolerance for the value of a given Parameters. Batches for which the value for the particular parameter is outside the acceptable range Tolerance range can be made by mixing with one or more batches that are sufficiently within the Tolerance limits are to be part of a mixture at which the value for the particular parameter is within is within the acceptable tolerance range. So far it has been a mixing process in which a series of individual Batches of a particulate material one at a time Container fed and the container subsequently emptied, the aim of the particulate matter as far as possible from all parts of the container at the same time remove.

The device according to the invention for mixing (snow-making dung) particulate matter comprises a number of containers, each of which has an inlet and, lying substantially perpendicularly below the inlet, with an outlet with a device

is provided to control the outgoing quantity, further means for distributing batches of the particulate matter to the containers, and a collecting container for receiving the particulate matter coming from the outlets, the one with an inlet and one with an outlet means for controlling the amount exiting therefrom is provided, the outlet being substantially vertical sits below the inlet.

The invention also provides a method of mixing a batch or a plurality of batches of a particulate Substance in which the batch or batches are divided between a number of containers, each of which has an inlet and, lying substantially perpendicularly below the inlet, with an outlet is provided with a device for controlling the outgoing flow therefrom, further gradually the particle-shaped Substance from each of the containers is transferred into a collecting container, the collecting container with a Inlet and an outlet lying substantially perpendicularly below the inlet with a control device the amount outgoing therefrom is provided, and in which subsequently the particulate matter exits through the outlet is discharged from the collecting container.

The degree of effectiveness of the mixing improves as the number of containers increases. It has been shown that 8 containers are very effective.

The degree of effectiveness of the mixture is also improved if the individual containers are constructed so that the particulate matter emptied from them by nuclear flow, so that as far as possible the river at all times and across the

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whole container proportions of as large a number as possible contains of layers. Core flow describes the state in which only part of the material is in one Vessel moves, in contrast to the ideal flow or the mass flow, in which during emptying the entire contents of the container moves. A core is one Column, which is usually perpendicular to the emptying point, which is either in the body of the container or can sit on the side or in a corner. Core flow is facilitated by the fact that the container and at the collecting container the outlet is perpendicularly below the inlet, so that the particles fall out in free fall come to the inlet and form a sloping layer, the highest point of which is perpendicularly below the inlet. The inlet is thus in a position from which the particulate material falls freely.

The containers may be in the form of many separate units, depending on the convenience of manufacture and / or operation or be set up as a single unit. For example, a cylindrical vessel with a conical base or a polygonal vessel with an inverted pyramid as a base through radial partitions in a number be subdivided by containers, in which case a single conduit will serve as an inlet for all containers or the inlets of each container may feed, and the outlet of all of the containers may be near the apex of the cone or the pyramid that form the bottom of the vessel, so that the flow of particulate matter from the individual containers is absorbed by a common service. Another option is distribution of the particulate material on the individual containers by a movable distributor, for example a loading

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weglich.es tube with a device for moving the free end such that the particle flow successively is directed into the various containers, can be facilitated. In the event of improvement of the Homogeneity of a quantity of particulate matter The filling of the container should preferably involve several revolutions of the filling device, or one good distribution between the tanks by a different distribution method.

In the case of mixing a number of batches of particulate matter, add to each of the containers a portion of each batch addressed, and filling a container necessarily involves more than two successive straightening of the particle flow to each container, but in the case mentioned it is even more preferable to interpose each batch to distribute the containers well by many cycles of the filling device or by another distribution method.

The mixing process according to the invention can at least to some extent recirculating the particulate matter into the mixing device, either within each level or in total.

Furthermore, the opening and closing parts can expediently len the flow from the sump with respect to the slope of the beginning and the end of the flow, for comparison to contain high proportions of comparatively fewer layers, for example the soil layer, special Attention should be paid. This includes the return

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lead a suitable initial and / or final part of the sump contents to the container, each portion serving as a batch of the particulate matter and is distributed to all containers. The initial and / or final portion can be distributed to the Be container to be segregated in a separate vessel.

Advantageously, each container should be completely in emptying the collecting container before starting to empty a second container.

Preferably the most distant part of the walls of the container should be from the inlet and outlet connecting vertical line must not be further than half the length of the vertical distance between inlet and outlet. Preferably, the walls of the container should be at least 1/6 of the vertical line vertical distance between inlet and outlet. It is even more preferred that the walls stand out from the vertical line at a distance of at least one third of the vertical distance between inlet and outlet.

Preferably the base of the container should be inclined upward away from the outlet. Preferably should the inclination is more than 30 in relation to the vertical, however, ensure that it is completely emptied.

Preferably the inflow of the particulate Substance into a container closely follow the vertical line between inlet and outlet.

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Preferably, a container should have such a sufficient cross-sectional area in proportion to the degree of heterogeneity of the particulate matter that layers of particulate Substances of essentially the same composition or properties are comparatively thin. So should Mixing a number of batches, each of which is homogeneous, built from one batch in a container Layer be comparatively thin, and the thinner the smaller the cross-sectional area of the container. Xin the cases where the cross-sectional area of a horizontal cut decreases as the outlet approaches and where therefore when in use of containers of the same size, the layer belonging to a container is thicker towards the bottom of the collecting container it may be advantageous to arrange it so that the volume of some of the vessels is smaller than that of the other containers, and that the collecting container holds the contents of the smaller containers in front of the The contents of the larger container and that the collecting container receives part of the contents of the smaller container according to the contents of the larger container.

In the context of the requirements mentioned, the containers have a variety of shapes. For example, the horizontal cross-section of each container can be cylindrical, be square, rectangular, or triangular. Another possibility, as already mentioned, is that the total number of containers is derived from a single vessel, which is inserted through partitions into the required Number of containers is divided. A particularly advantageous arrangement is with a vessel octagonal cross-section and a base in the form of an inverted octahedral pyramid, wherein

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the outlet is at the top of the pyramid and an inlet is provided perpendicularly above the outlet. That Vessel is through vertically arranged partitions, which are in the vertical line between outlet and inlet cut, divided.

The collecting container should advantageously be shaped in such a way that that the most distant part of the edge from the vertical line connecting the inlet and outlet is no more than half the distance between the inlet and outlet. Preferably the walls should of the collecting container from the vertical line at least 1/6 of the vertical distance between inlet and outlet be distant. It is even more preferred that the walls extend from the vertical line in at least 1/3 of the vertical Extend distance between inlet and outlet.

Preferably, the base of the collecting container should be inclined upwards, away from the outlet. Preferably the inclination to the vertical should be more than 30

ensure.

30, but a complete emptying is possible.

The degree of effectiveness of the mixing is also improved, if the sump is constructed so that the particulate is emptied by core flow and the flow as far as possible at all times from a representative fraction of at least one, and preferably several, the composite layers is formed from the individual containers.

The invention therefore also provides a method for mixing one batch or a plurality of batches of one

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particulate matter in which the batch or the Batches are distributed to a number of first piles with a given horizontal cross-section, with the supply for each first heap falls into an area with a smaller area than the cross-sectional area of each first heap, in which the first heaps are successively entirely in one place within and at the bottom of each first pile, the is smaller in its horizontal extent than that of the first cluster and is within the vertical projection the area of delivery of the particulate matter to the first pile sits or contains this, to a second pile with a predetermined horizontal cross-sectional area removed, the feed to the second pile in an area smaller than the cross-sectional area of the second Heap falls, and at which afterwards the second heap of a point which lies within and at the bottom of the second heap and is smaller in the horizontal extent than that is the second pile and lies within the projection of the area of the supply of the particulate matter or these contains is removed.

The particle feed should preferably be to a collecting container closely follow the vertical line between the inlet and the outlet.

The collecting container should preferably have such a sufficient cross-section in relation to the container volume, that the particle layer originating from the contents of a container in the collecting container is comparatively thin, and the thinner the smaller the cross-sectional area of the Collection container is. The latter should preferably be at least equal to the sum of the cross-sectional areas of the

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be holder.

Taking into account the requirements mentioned, the collecting container have a variety of shapes. For example, it can be cylindrical or polygonal in cross-section, for example square, rectangular or triangular or octagonal.

While this is not critical, the containers can be positioned above the collection container so that the flow from them to the collecting tank takes place under the influence of gravity. Otherwise, precautions are necessary a transfer from the outlet of the container to the inlet of the collecting container, for example by entrainment in an air stream.

The following is a preferred embodiment of the Invention described in connection with the accompanying drawing. On this shows

1 shows an octagonal vessel with eight containers in plan,

FIG. 2 shows a side view of the vessel from FIG. 1,

3 shows the shape of a partition wall of the vessel from FIG. 1,

K shows a collecting container with an octagonal cross-section in plan,

Fig. 5 is a side view of the collecting container from Fig. H _f

6 shows the arrangement of the vessel from FIG. 1 above the collecting container,

Fig; 7 shows a vertical section along line A-B through a the container of the vessel from Fig. 1 and

Figure 8 shows the profile of the particulate material during Emptying process.

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In FIGS. 1, 2 and 3 is a vessel with 8 partitions ABCD shown with each other along line AD, with a rectangular plate 2 along line BC and with a triangular plate 3 are connected along line CD, so that eight containers 4 result. The length AB was 365.76 cm (12 feet), the length BC 640.08 cm (21 feet), the length AD 975.36 cm (32 feet) and the angle ABC 47 ° 16 ·. The slope of the bottom of each container was 45 against the vertical.

A drain with closures which can be operated separately for the containers is near the lowest point of the container arranged :. A roof covering the top of all containers is in the middle of the container group with one for a sufficiently wide opening to fill all containers at the same time.

The FIGS. 4 and 5 show a collecting container made of rectangular plates 5 with a length of 640.08 cm (21 feet) and a width of 280.41 cm (9.2 feet) and triangular plates 6 with a side length of 280.41 cm (9.2 feet) for one side and with one side length of 457> 20 cm (15 feet) for the remaining two Pages is formed.

At the lowest point of the collecting container is a circular one provided with a closure for emptying it Orifice with a diameter of 15> 24 cm (6 inch) intended.

In operation, the particulate matter is in a stream of air through a pipe 7 (Fig. 6) in all containers 4 of the

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Vessel 8 taken into it, being close to the Center axis of the vessel 8 enters the individual container. Each batch of particulate forms a substantially uniformly thick layer sloping towards the outside of the vessel 8. The outlet opening one of the containers is then opened and gradually delivers its contents under the action of gravity a funnel 9 and from here in the upper part of its central axis to a collecting container 10. The flow of the particulate Substance from the container 4 takes place so that a sliding of the substance over the layers of each Batches to form a profile as shown in Fig. 8 is carried out. Therefore a noteworthy one ensues Mixing adjacent batches during the emptying of the container 4, after emptying the first Container 4 becomes the outlet opening of a second container 4 opened, whereby its contents can be dispensed in the collecting container 10, etc. for all containers 4. The contents of each container 4 forms a conical heap in the collecting container 10, with each container filling forms a sheet of particulate matter of substantially uniform thickness. With the Opening the outlet opening of the collecting container 10 flows the central core of the particulate matter first. The contents of the collecting container are emptied through this core from a conical shaft on the surface, which cuts through several adjacent container layers. As a result of this final mixing the outgoing flow from the sump contains a portion over the greater part of this flow of each original batch of the particulate matter, whereby a satisfactory blending or blending

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of the total particulate matter is achieved.

In the following special embodiments of the invention Method of performing mixing described. Eight containers are referred to for simplicity of description, but the method is in principle not limited to this number.

1, remixing process

After roaring the eight containers so that each one Contains proportion of all batches to be mixed with one another, a container is emptied into the collecting container, and thus causing a misuse. This amount of particulate matter is then placed in the empty container returned. This container is denoted by 1, the remaining containers may be numbered from 2 to 8 be. The same thing happens to the eighth container as to the first. The eight containers now become one one after the other in the order 1 to 8 emptied into the collecting container. This ensures that the The bottom and top of the contents of the collecting container are well mixed before the final Mixing is effected by the process of emptying the collecting container.

2. Split tank method

Here reference is made to containers on the assumption that the device used is constructed as shown in FIG. 6 and that a container makes up 1/8 of the volume of the upper vessel. In principle, this method can also be used with a different number of containers, which are not necessarily in the form of a common vessel with separation

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walls must be available. That is, each container can be a separate vessel.

Bai numbering of the containers with 1 to 8, is the first divided into two containers 1A and 1B by a partition. After distributing the batches to mix such that each container, including containers, 1A and 1B, has a portion of each batch of particulate matter, the nine containers are arranged one after the other in the following Sequence emptied into the collecting container: 1B, 2, 3, 4, 5> 6, 7 »8, 1A. Another improvement on the Mixing can be achieved by first emptying 1B into the collecting container and following IB is returned, and by first emptying 1A into the collecting container and returning to 1A before continuing with emptying the container in the manner described.

3 « Use of an auxiliary holding vessel

In addition to the vessel comprising eight vessels and the collecting vessel, an auxiliary vessel is provided. This can, for example, have a capacity which corresponds to the volume of the tapering base part particulate matter contained in a container is equivalent to. After distributing the batches so that each container contains a portion of each batch, the Particulate matter contained in the tapered base of the first container for an auxiliary vessel branched off. The remaining contents of the first container are drained into the collecting container, and during this time the contents of the auxiliary vessel so emptied into the collecting container that it is

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in the bulk of the particulate matter des evenly distributed in the first container. Then the contents of the containers 2 to 8 are in the collecting container emptied. The collecting container is then emptied and the mixing is completed in this way. Preferred If the auxiliary vessel is used in conjunction with the under 1, remixing process described is used.

k. "Continuous" operation

After filling the eight containers in such a way that each one Contains portion of each of the batches to be mixed, and after successive emptying each of the eight containers the portion of emptied particulate matter which is less well mixed is in the collecting container is, that is approximately the first 15 percent in the case of the sump shown in Fig. 4, from the sump drained and evenly distributed among the eight containers. The next about 75 percent the contents of the sump are then drained for use as a mixture. In the meantime a equal amount of fresh, unmixed batches evenly distributed over the eight containers. The last about 10 percent of the contents of the collecting container, which are also less well mixed, are then removed from the Drain the collecting container and distribute it approximately evenly over the eight containers. After that the whole Mixing process repeated. Percentages greater than 25 percent may enter the circulation if necessary to be led back.

5. Double shuffling

The containers are numbered from 1 to 8. Every

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of the batches to be blended is distributed among the containers so that each contains a portion of each of the batches to be mixed. The containers are drained into the collecting container one after the other in the order 1, 2, 3, 4, 5, 6, 7, 8. The collecting container is emptied and the contents are returned directly to the eight containers, this time being filled one after the other in the order 1, 2, 3> 4, 5 »6, 7> 8. The filling is arranged so that approximately equal amounts are supplied to all containers. The containers are then emptied into the collecting container one after the other in the following order: 5, 6, 7, 8, 1, 2, 3, K. The collecting container is then emptied while mixing is complete.

To make it easier to empty the containers in the correct order and to correct the proportions Program-controlled valves can be used to advantage.

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Claims (16)

Patent claims 1. A device for mixing particulate materials, characterized by a plurality of containers, each of which is provided with an inlet and lying substantially vertically below the inlet, with an outlet with a device for controlling the emptying of this _s by means for distributing batches of particulate matter to the containers, and through a collecting container for receiving the particulate matter coming from the outlets, the collecting container having an inlet and an outlet located substantially perpendicularly below the collecting container inlet with means for controlling the Emptying from this is provided. 2. Device according to claim 1, characterized in that that the number of containers is eight. 3. Apparatus according to claim 1 or 2, characterized in that all containers and the collecting container so are constructed that the emptying of the particulate Matter from them by core flow is going on. 4. Device according to one of claims 1 to 31 characterized in that the containers are arranged in a single unit. 5. Apparatus according to claim 4, characterized in that that the containers together form a cylindrical vessel with a conical base or a polygonal shape 709316/0651 can measure an inverted pyramid as a base form in which a single conduit is arranged to act as an inlet for all of the containers serves or feeds the inlets to the individual containers, and in which a single line the Receives flow from all reservoirs. 6, device according to one of claims 1 to 5> characterized in that the outlets of the containers are at a higher level than the inlet of the collecting container, so that gravity flow is possible from the individual containers to the collecting container. 7 »Device according to one of claims 1 to 6, characterized in that with all containers and with the Collection container the furthest part of the wall from the vertical line connecting between the inlet and outlet are less than half the vertical distance between inlet and outlet is. 8, device according to one of claims 1 to 7 »thereby characterized in that the walls of all containers and of the collecting container are separated from those connecting the inlet and the outlet vertical line are at least 1/6 of the vertical distance between inlet and outlet. 9. Device according to one of claims 1 to 7 »thereby characterized in that the walls of all containers and des Collecting container from the vertical line connecting the inlet and outlet at least 1/3 of the vertical Distance between inlet and outlet are removed. 709816/0861 10. Device according to one of claims 1 to 9 »characterized in that the bases of all Container and the collecting container is inclined upwards away from the outlet. 11. The device according to claim 10, characterized in that that the slope is more than 30 against the vertical, but the one complete emptying nor permitting inclination does not exceed. 12. Device according to one of claims 1 to 11, characterized in that for all containers and for the inlet is constructed in such a way that the flow of the particulate matter is narrow vertical line between inlet and outlet follows. 13. Method of mixing one or more batches Batches of particulate substances, thereby identified . draws that the batch or batches on a number of first piles with certain horizontal Cross-sectional area are distributed, with the feed to all first clusters in an area of smaller cross-sectional area than that of each first heap, that successively every first heap at a place within and at the bottom of it, which is smaller in its horizontal extent than that of the first pile and within the vertical projection of the area of the supply of particulate matter to the first heap, or this contains, removed and a second heap formed with a certain horizontal cross-sectional area the feed to the second heap in an area with a smaller cross-sectional area than that 709818/0851 of the second pile falls, and that after that, the second Pile at one point inside and at the bottom of the same, which is smaller in its horizontal extent than that of the second heap and is within the vertical projection of the area of feed of particulate matter lies in the first pile or this contains is removed. 14. Method of mixing one or more batches Batches of particulate matter, characterized in that that the batch or batches are divided into a number of containers, each of which with an inlet and, lying essentially vertically below the inlet, with an outlet with a Means' for controlling the outgoing flow is provided that the particulate material after and thereafter transferring from each of the containers to a collection container, the collection container having an inlet and, lying substantially perpendicularly below the inlet, with an outlet with means for controlling of the outgoing flow is provided, and that thereafter the particulate matter through the outlet from the Collection container is emptied. 15 «Method according to claim I3 or 14, characterized in that that at least a portion of the particulate matter, either in each stage or in total, in the Mixing device is returned. 16. The method according to claim 15 »characterized in that the returned portion is that which the initial or final batch of the collection container or both. 709816/0851 17. The method according to claim 16, characterized in that that the initial share is 15 percent and the final share 10 percent. 7Q981S / 0351