BE1022047B1 - TREATMENT DEVICE AND TREATMENT PLANT FOR SCHÜTTGUT - Google Patents

Abstract

A treatment device for bulk material has a container (12) for the bulk material with a container interior which has a supply opening and a discharge opening. A weighing device is used to weigh the bulk material present in the container (12). Mixed gas can be introduced into the interior of the container via at least one gas supply nozzle (17). The result is a compact treatment system with such a treatment device.

Description

Treatment device and treatment plant for bulk material

The content of German Patent Application DE 10 2012 208 717.6 is incorporated herein by reference.

The invention relates to a treatment device for bulk material. Furthermore, the invention relates to a treatment plant for bulk material with at least one such treatment device.

For the production of bulk mixtures, weighing and / or mixing devices are known from the prior art. Examples of this and examples of further prior art in connection with bulk goods containers are given in DE 24 22 963 B1, US Pat. Nos. 3,385,724, DE-PS 1,172,934, WO 99/64767 A1, DE 1 432 030 A, US Pat DE-PS 2 121 636, DE 25 22 088 C2, DE 100 07 718 CI, DE 102 36 520 A1, DE 0 088 638 B1, EP 1 125 628 B1, EP 1 512 643 B1, the GB 2 348 636 B, US Pat. No. 4,012,348, WO 91/15347 A1, EP 0 099 419 A1, EP 41 19 033 C2 and DE 1 757 028 A. From DE 40 29 902 C2, there is a suction conveying fan realized suction promotion known.

A treatment device for bulk material is typically part of a treatment plant whose components are arranged on several levels one above the other, between which usually takes place a gravimetric bulk material and / or additive promotion.

It is an object of the present invention to develop a treatment device of the type mentioned in the beginning such that a more compact treatment plant results.

This object is achieved by a treatment device having the features specified in claim 1.

According to the invention, it has been recognized that both weighing and mixing of the bulk material can take place in the treatment apparatus. This saves the use of such a treatment device in a treatment plant, a component level, since typically in the known treatment plants in a first, upper level, first weighing takes place and in a second, underlying level, a mixing of the weighed bulk solids. By combining the functions "weighing" and "mixing" in one and the same treatment device, one of these two levels can now be saved. In addition, the integration of the functions "weighing" and "mixing" in one and the same treatment device results in an overall compact weighing / mixing device. This results in a more compact in terms of height treatment plant. With the help of the at least one gas supply nozzle mixing of granules and / or mixing of powder components is possible. The treatment device is particularly suitable for the treatment of plastic bulk materials, which may be starting materials, for example, for compound production. In addition, a visual effect can be brought about via the introduction of mixed gas, in which undesirable small bulk material fractions can be separated. The mixed gas can be introduced in the form of mixed gas pulses. The treatment device may be part of a treatment plant whose components are arranged on several levels one above the other, but can also be used independently for weighing and mixing of bulk material.

A suction conveyor according to claim 2 has been found in practice to be particularly suitable. Alternatively, a pneumatic pressure transfer for conveying the bulk material and in particular various bulk material components in the container is possible.

A plurality of gas supply nozzles according to claim 3 has been found to be particularly suitable for efficient mixing of the bulk material. The gas supply nozzles can be aligned with the container so that, for example, a twist angle of a mixed gas supply can be predetermined, so that the mixed gas is introduced into the container interior, for example with a tangential pulse component. It is therefore possible to specify an initial impulse direction of a gas inlet for optimizing a mixing result. The number of gas supply nozzles may be in the range between two and twenty. In particular, four, six, eight, ten, twelve or fifteen gas supply nozzles may be used.

An annular nozzle arrangement according to claim 4 has been found to be particularly suitable for achieving an efficient mixing result.

An arrangement of the nozzle according to claim 5 avoids dead volumes in which no or a little effective mixing takes place.

A clamping unit according to claim 6 enables automated emptying of a weighed and mixed bulk container contents.

A closing unit with a closing cone according to claim 7 is safe and robust. A closing cone also favors a geometry of the container interior without disturbing dead volumes.

Guide plates according to claim 8 have been found to be particularly suitable for optimizing a mixing result. The baffles can, if a closing cone is used, be attached to an outer wall of the closing cone. The baffles can be made exchangeable and / or relocatable. About the baffles a swirling motion of the mixed gas and / or the bulk material to be mixed can be achieved.

A diameter ratio between the diameter of the discharge opening on the one hand and the diameter of the at least one gas supply nozzle on the other hand according to claim 9 results in particular, when the at least one gas supply nozzle is arranged in the region of the discharge opening, a particularly efficient mixing result. The ratio between the diameter of the discharge opening on the one hand and the diameter of the at least one gas supply nozzle on the other hand may be in the range between eleven and forty and may be in the range between fifteen and thirty.

A self-closing nozzle according to claim 10 avoids undesirable backflow of the bulk material into a nozzle channel of the at least one gas supply nozzle. An interior of the treatment device can then be designed to be wet-cleanable without undesirably penetrating cleaning fluid into the nozzle channels. The treatment device with the at least one self-closing gas supply nozzle can be used for food or for sensitive specialty products.

An embodiment of the at least one gas supply nozzle for sifting the bulk material according to claim 11 can be used in the case of granules to be treated. About the mixed gas, which is introduced via the at least one gas supply nozzle into the container interior, the bulk material is thereby whirled so that solve small bulk material and in particular dust from the granules. A gas exit velocity of the mixed gas from the at least one gas supply nozzle may be in the range between 20 m / s and 300 m / s at the nozzle exit. An amount of air, which is introduced into the container interior for mixing and sifting, in particular via the at least one gas supply nozzle, can be chosen so large that the small bulk material components separated during the sifting remain in motion and via a discharge pipe , which discharges from the container in the classifier variant, are led to a separate filter. In an alternative embodiment of an arrangement of such a filter, this can be constructed directly on the container and can be designed so that the filter cleans into the container interior. This avoids that bulk material is lost during the visual process.

The advantages of a treatment plant according to claims 12 and 13 correspond to those which have already been explained above with reference to the treatment device.

A Ausfühmngsbei game of the invention will be explained in more detail with reference to the drawing. In this show:

1 shows very schematically a system diagram of a plant for the treatment of bulk material with a weighing / mixing treatment device;

2 shows an axial longitudinal section through a bottom-side mixing section of the treatment device, wherein a closing unit of a mixing / mixing container of the treatment device is shown in a closed position; and

Fig. 3 in a similar to Fig. 2 representation of the treatment device with the closing unit in the open position.

An apparatus 1 for the treatment of bulk material is used for mixing dosed portions of various polymers and also for precise metering of several additives in the prepared polymer mixture and for the subsequent extrusion of the resulting polymer / additive blend. Appendix 1 is described using the example of mixing three polymers and adding three additives. It is understood that other numbers of polymers can be mixed and other numbers of additives added. With the Appendix 1 and other recipe ingredients can be processed, eg. B. rubber in granular form.

The plant 1 is arranged in three vertically stacked plant levels 2, 3 and 4.

In the lowest level 2 storage containers 5, 6 and 7 are arranged for the polymers to be processed, which are kept as plastic granules. Via conveying lines 8, 9 and 10, the polymers from the three storage containers 5 to 7 are conveyed into a bulk material handling device 11, which is arranged in the uppermost level 4 of the system 1. The delivery lines 8 to 10 open via a feed opening in the cradle / mixing container 12. The treatment device 11 serves on the one hand for weighing the three polymer components, the treatment of the

Device 11 are supplied, and on the other hand for mixing these polymer components.

The polymers are conveyed from the storage containers 5 to 7 into a weighing / mixing container 12 of the treatment apparatus 11 by means of a pneumatic suction conveyor. The weighing / mixing container 12 is for this purpose in fluid communication with a vacuum source 13, which provides for a negative pressure in the cradle / mixing container 12, through which the bulk material is sucked from the storage containers 5 to 7. The vacuum source 13 is part of a suction conveyor of the treatment device 11.

The weighing / mixing container 12 has a volume that is less than 10m3. The volume of the weighing / mixing container 12 may be less than 5m3 and may be in the range of 2m3.

Part of the treatment device 11 is a weighing device 14 with a plurality of load cells 15, on which the weighing / mixing container 12 stores.

A bottom-side and downwardly conically tapered mixing container section 16 communicates with a plurality of gas supply nozzles 17, of which only one is shown schematically in FIG. 1, in fluid communication. The mixing container section 16 represents a discharge section of the weighing / mixing container 12. Via the gas supply nozzles 17, mixed gas can be introduced for mixing the bulk material into the interior of the mixing container section 16, ie into the interior of the weighing / mixing container 12. The mixed gas can be introduced in pulses and at high speed. It may be sufficient, only a few mixed gas pulses, z. B. two or three mixed gas pulses to initiate. The duration of a mixed gas pulse may be less than 30 seconds.

The bulk material may be in the form of at least one granulate component and / or at least one powder component.

The gas supply nozzle 17 is connected via a gas line 18 with a pressure accumulator 19 in fluid communication. The gas supply nozzles 17 are designed to be self-closing.

A bottom-side outlet of the mixing container section 16, which is formed in the form of an annular gap or an annular channel, which will be explained in more detail below, is in fluid communication via an outlet line 20 with a gravimetric dosing unit 21, via which a dosing quantity of the polymer mixture is exactly predetermined for further processing can be. The promotion in the output line 20 is carried out gravimetrically. A delivery of the polymer mixture from the cradle mixing container 12 can also be done in a pure receiving container with subsequent conveyor.

The polymer dosing unit 21 is arranged in the second, middle level 3 of the system 1. Via a polymer dosing line 22, the polymer dosing unit 21 is gravimetrically in fluid communication with an inlet funnel 23 of an extruder 24. The extruder 24 is arranged in the lowest level 2.

In the uppermost level 4, in addition to the treatment device 11, there are also supply containers 25, 26 and 27 for the three additives, which are metered into the polymer mixture. The additive reservoirs 25 to 27 are each in fluid communication via an outlet line 28, 29 and 30 with their own gravimetric additive metering devices 31, 32 and 33. The additive delivery in the output lines 28 to 30 is carried out gravimetrically. The additive metering devices 31 to 33 are arranged in the second level 3 next to the polymer metering device 21. Via additive metering lines 34, 35 and 36, the additive metering devices 31 to 33 are in fluid communication with the inlet funnel 23. The additive delivery through the additive metering 34 to 36 also takes place gravimetrically.

2 shows details of the mixing container section 16 of the bulk material treatment apparatus 11. A bottom-side discharge opening 37 of the weighing / mixing container 12 is closed by a closing unit in the form of a stroke-displaceable closing cone 38. The discharge opening 37 is in fluid communication with the outlet line 20.

A diameter ratio between a diameter of the discharge opening 37 on the one hand and the nozzle diameter of the gas supply nozzles 17 on the other hand in the embodiment of FIG. 2 is about twenty-five. Other diameter ratios in the range between four and sixty are possible.

The closing cone 38 is shown in Fig. 2 in a closed position. In this an outer cone wall of the closing cone 38 is on all sides via a seal at a boundary of the discharge opening 37, so that the discharge opening 37 and thus the cradle / mixing container 12 is closed fluid-tight and in particular gas-tight. Via a reciprocating piston unit 39 with one or more reciprocating pistons, which can be pneumatically controlled for stroke displacement, the closing cone 38 can be displaced between the closed position of FIG. 2 into an open position, which is shown in FIG. In this, the closing cone 38 releases an annular space or annular gap 40 for discharging the bulk material through the discharge opening 37 to the output line 20.

Near the discharge opening 37, the gas supply nozzles 17 open into the mixing container section 16 on the bottom side. The gas supply nozzles 17 are thus arranged in the region of a discharge section of the weighing / mixing container 12. A total of eight such gas supply nozzles 17 are provided, which are arranged distributed in the circumferential direction around the mixing vessel portion 16 around. Also, a different number of gas supply nozzles 17 is possible. Mixed gas can be introduced via nozzle openings 41 in the container interior of the cradle / mixing container 12. The nozzle openings 41 can be closed by a respective plunger 42 housed inside a housing of the gas supply nozzle 17, which can be displaced pneumatically via a control line between a closed position and an open position. Nozzle heads 43 of the gas supply nozzles 17 are fitted in complementary thereto receiving openings in the mixing container section 16 so that the nozzle heads 43 terminate flush with the inner container wall and an edge-free transition between the inner container wall of the cradle / mixing container 12 and the nozzle heads 43 is ensured ,

For controlling the reciprocating piston unit 39 and the pneumatic displacement of the plunger 42, these components are in a manner not shown with a central control device 44 of the system 1 in signal communication. In particular, an addition of mixed gas pulses into the container interior of the weighing / mixing container 12 can take place via activation of the tappets 42. The introduction may be in the form of a mixed gas pulse train with, for example, two or three mixed gas pulses. Each mixed gas pulse may have a duration less than 30 seconds.

The outer conical wall of the closing cone 38 carries baffles 45 for guiding on the one hand the mixed gas leaving the nozzles 17 and on the other hand the bulk material entrained in the mixing process. The baffles 45 spirally wound around the outer wall of the closing cone 38. The baffles 45 may be fixed to the locking cone 38 and permanently attached thereto, for example, be integrally connected thereto. Alternatively, the baffles 45 may also be detachably, in particular interchangeable and / or displaceable mounted on the closing cone 38. In this way, a guiding behavior of the guide plates 45 can be adapted to the bulk material to be mixed and to feed conditions of the mixed gas via the nozzles 17.

The nozzles 17 can open vertically into the conical container wall of the mixing container section 16, so that mixed gas from the mixing nozzles flows in with a main impulse component which runs perpendicular to the container wall of the mixing container section 16. Alternatively or additionally, it is possible to arrange the nozzles 17 inclined to the container wall of the mixing container 12, so that a tangential and / or axial initial flow of the mixed gas is achieved when flowing into the mixing container section 16.

The closing cone 38 is supported by a support flange 46, which is bolted to a mounting flange 47 on the cradle / mixing container 12.

During operation of the system 1, first the three polymer components are conveyed via the lines 8 to 10 into the cradle / mixing container 12. This can be done sequentially, so that the respective weight of the individual polymer fraction can be accurately determined via the weighing device 14. The closing cone 38 is here in the closed position. After the exact metering in of the three polymer components, mixed gas is introduced via the gas supply nozzles 17 into the mixing container section 16, the closing cone 38 remaining in the closed position. The polymer components are thereby mixed in the cradle / mixing container 12 under the action of the mixed gas, wherein at the same time a visual effect may occur, so that undesirably small particle sizes of the polymer components can be derived from the cradle / mixing container 12 via a separation line, not shown. In the Abscheideleitung, which is designed as opening out of the container 12 pipe, a filter is arranged, to which the undesirably small bulk material shares are discharged. An amount of air that is introduced via the nozzles 17 into the interior of the cradle / mixing container 12, is so large that the undesirable small bulk solids do not settle on the way to this filter. A gas velocity at which the mixed gas exits the gas supply nozzles 17 during mixing and / or sifting is in the range between 20 m / s and 300 m / s at the nozzle outlet.

In an alternative variant of the system 1, a separation filter for the deposited in sifting unwanted small bulk material shares directly on the cradle / mixing tank 12 is built on. The separating filter arranged in this way can be cleaned directly into the cradle / mixing container so that no bulk material is lost.

After mixing, the mixed gas supply via the nozzles 17 is stopped and the closing cone 38 is moved to the open position. Subsequently, over the

Polymer metering device 21 and the three additive metering devices 31 to 33 gravimetrically a predetermined ratio of the polymer mixture and the three additives fed to the inlet hopper 23. The polymer mixture together with the additives can then be further processed in the extruder 24.

As far as the above visual effect of the mixed gas is utilized, the method steps "sifting" and "weighing" can also interchange their order.

Claims (13)

claims A bulk material handling apparatus (11) comprising a bulk container (12) having a container interior having a feed opening and a discharge opening (37) with weighing means (14) for weighing in the container (12) Bulk solids, with at least one gas supply nozzle (17), can be introduced via the mixed gas for mixing the bulk material in the container interior. 2. Treatment device according to claim 1, characterized by a suction conveyor for feeding the bulk material in the container (12). 3. Treatment device according to claim 1 or 2, characterized by a plurality of gas supply nozzles (17). 4. Treatment device according to claim 3, characterized in that the gas supply nozzles (17) are arranged annularly around the container (12) around. 5. Treatment device according to claim 3 or 4, characterized in that the nozzles in the region of a discharge section (16) of the container (12) are arranged. 6. Treatment device according to one of claims 1 to 5, characterized by a closing unit (38) for controllably closing the discharge opening (34). 7. A treatment device according to claim 6, characterized in that the closing unit (38) has a hubverlagerbaren cone which rests in a closed position on all sides at a boundary of the discharge opening (37) and in an open position an annular gap (40) for discharging bulk material through the Discharge opening (37) releases. 8. Treatment device according to one of claims 1 to 7, characterized by baffles for mixed gas flow and / or bulk material management. 9. Treatment device according to one of claims 1 to 8, characterized by a diameter ratio of a diameter of the discharge opening (37) on the one hand and a diameter of the at least one gas supply nozzle (17) on the other hand in the range between four and sixty. 10. Treatment device according to one of claims 1 to 9, characterized in that the at least one gas supply nozzle (17) is self-closing. 11. Treatment device according to one of claims 1 to 10, characterized in that the at least one gas supply nozzle (17) is designed such that via a mixing gas introduction of the at least one gas supply nozzle (17) is brought about a visual effect, in which unwanted small bulk solids are deposited. 12. bulk material treatment plant with at least one treatment device according to one of claims 1 to 11. 13. Plant according to claim 12 with at least one additive metering device (31 to 33) for the metered addition of an additive to the weighed and mixed bulk material.