EP2273221B1 - Device for cooling bulk goods and method for treating bulk goods - Google Patents

Description

The invention relates to a device for cooling bulk material. Furthermore, the invention relates to a method for treating bulk material.

Devices of the type mentioned are known from the DE 10 2007 027 967 A1 , of the DE 10 2004 041 375 A1 , of the EP 0 444 338 B1 , of the DE 196 43 699 C1 , of the DE 36 39 046 A1 , of the DE 31 31 425 A1 , of the AT 205 008 B and the CH 296 419 A and the EP 1 975 536 A2 ,

• mit einem Schüttgut-Eintragsmodul,
• mit einem dem Schüttgut-Eintragsmodul im Förderweg des Schüttguts nachgeordneten Schüttgut-Wärmetauschermodul mit einer Mehrzahl von Wärmetauscherelementen, die in thermischem Kontakt mit einem Kühlmedium stehen,
• mit einem Schüttgut-Austragsmodul,
• wobei in das Schüttgut-Eintragsmodul eine Gas-Zuführleitung zur Einleitung eines Trocknungsgases einmündet, wobei das Schüttgut-Eintragsmodul so ausgeführt ist, dass eine Verweilzeit des Schüttguts im Schüttgut-Eintragsmodul gegeben ist,
• wobei das Schüttgut-Eintragsmodul einen Konusabschnitt aufweist, in dem das Schüttgut längs mindestens eines sich in Förderrichtung verjüngenden Trichters geführt ist, der zu einem Sammelraum des Schüttgut-Eintragsmoduls führt,
• wobei die Gas-Zuführleitung derart in den Sammelraum einmündet, dass ein unerwünschtes Anbacken des Schüttguts vermindert oder ganz vermieden ist.

EP 1 975 536 A2 discloses a device for cooling bulk material

• with a bulk material entry module,
• with a bulk material heat exchanger module arranged downstream of the bulk material feed module in the conveying path of the bulk material, with a plurality of heat exchanger elements which are in thermal contact with a cooling medium,
• with a bulk material discharge module,
• wherein a gas feed line for introducing a drying gas opens into the bulk material feed module, wherein the bulk material feed module is designed such that a residence time of the bulk material is given in the bulk material feed module,
• wherein the bulk material infeed module has a conical section in which the bulk material is guided along at least one funnel tapering in the conveying direction, which leads to a collecting space of the bulk material infeed module,
• wherein the gas supply line opens into the collecting space such that an undesired baking of the bulk material is reduced or completely avoided.

It is an object of the present invention to develop a cooling device of the type mentioned in such a way that an undesirable caking of the bulk material, in particular at the heat exchanger elements is reduced or completely avoided.

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

According to the invention, it has been recognized that the reason for the caking is that the bulk material with a residual moisture content above a moisture standard value in contact with the heat exchanger elements tends to agglomerate and thus caking. An absolute value for the humidity default value, below which an agglomeration tendency is sufficiently low, depends on the bulk material used, depending on the particle shape of the bulk material, depending on the particle size distribution of the bulk material as well as on the method for producing the bulk material. It is true that a large surface of the bulk particles promotes leakage of moisture from the interior of the particle. It has been found that drying in the bulk material entry module, which leads to a reduction of the moisture, for example at 150 ° C. by more than 100 ppm, already greatly reduces the unwanted caking of the bulk material at the heat exchanger elements. The moisture content of the bulk material can be reduced by more than 300 ppm, by more than 500 ppm, or by more than 1000 ppm, measured at 150 ° C during the predrying in the bulk material injection module. By using the gas supply line according to the invention for introducing a drying gas, a predrying of the bulk material in the bulk material entry module, ie in the conveying path of the bulk material in front of the bulk material heat exchanger module, can be achieved so that a residual moisture of the bulk material results below the default value, which in turn leads to this in that the bulk material does not or hardly caking on the heat exchange elements. This increases the service life of the cooling device in comparison to the prior art, in particular the cleaning intervals, after the expiration of the next cleaning of the cooling device is due. As a result of the predrying according to the invention in the bulk material injection module, moisture can be prevented from flowing out of the individual bulk material particles as long as the bulk material requires transport through the bulk material heat exchanger, in particular for gravimetric flow. As bulk material, fertilizers, salts, sugars, biomass or other bulk materials can be used. As the drying gas, air or nitrogen or other gas can be used. In particular, when not air, but another drying gas is used, the drying gas may be performed in a circulatory system of the cooling device. The drying gas can, if air is used, be sucked from the environment. The drying gas may also be provided by a gas source. The gas supply line can simultaneously a bulk material supply nozzle represent. In this case, it is possible to use a bulk material entry module without major structural changes within the cooling device according to the invention. The cooling device may have a suction device for the drying gas, which may have a downstream dedusting device. Such dedusting can be ensured by a cyclone and / or by a filter. The bulk material entry module can be used simultaneously as a classifier unit of the cooling device. In this case, the drying gas can simultaneously take over the function of a visual gas. In this way, for example, dust particles can be separated from the bulk material within the cooling device. This separation also increases the service life of the cooling device and the cleaning intervals, since the unwanted deposition or unwanted caking liable dust particles are removed from the interior of the cooling device. To even out the entry of the bulk material in the bulk material entry module may be used for deflecting the bulk material conveying a scattering device. The heat exchanger elements can be designed as heat exchanger plates or as heat exchanger tubes. The heat exchanger tubes can be arranged along the bulk material conveying direction and lead, for example, the bulk material. Alternatively, it is possible to arrange the heat exchanger elements transversely or perpendicular to the bulk material conveying direction in the heat exchanger module. In this case, the heat exchanger elements lead the cooling medium. The execution of the bulk material entry module is such that the residence time of the bulk material in the entry module is greater than 1 min. This leads to an effective drying of the bulk material. It is not necessary that the bulk material supplied to the cooling device is already pre-dried. The bulk material can be provided before drying with a residual moisture content, for example, 3%. The residual moisture is defined as the ratio of the weight weight of the moisture content to the weight of the bulk material. The drying or residence time may be greater than 2 minutes, may be greater than 3 minutes, may be greater than 5 minutes, may be greater than 10 minutes, may be greater than 20 minutes, may be 30 minutes and may be greater than 30 min. Dwell times greater than 1 min can be achieved by the targeted generation of a product jam in the bulk material entry module. The bulk material injection module is designed such that substantially a fixed-bed flow through the drying gas is achieved by the bulk material present in the entry module. The drying then takes place by a diffusion process, ie the moisture evaporates or evaporates on the surface of the bulk material particles and is taken up by the drying gas. The bulk material injection module has a cone section in which the bulk material is guided along at least one funnel or cone tapering in the conveying direction with a round or rectangular dispensing opening leading to a collecting space of the bulk material feed module, the gas feed line opening into the collecting space. Such a cone section enables a good distribution of the drying gas and the bulk material over the cross section of the bulk material entry module and, correspondingly, an efficient drying of the bulk material. The upper portion of the heat exchanger module, in such a construction, may be readily accessible for side cleaning via inspection ports at the periphery of the bulk material entry module or heat exchanger module. The funnels can be designed as round or rectangular cones with round or rectangular dispensing openings. A plurality of such cones can be arranged one inside the other, in particular concentrically one inside the other, so that there are annular circumferential discharge openings for the bulk material. In rectangular executed housing shape of the bulk material entry module and / or the heat exchanger module can also angerannete side by side Funnels with round discharge openings or even rectangular cones with round or rectangular discharge openings for the bulk material can be used. The housing of the bulk material entry module may have a round or a rectangular cross-section. The at least one funnel may have a slot-shaped dispensing opening. The at least one funnel may have an annular circumferential discharge opening, which may be round or rectangular. In this case, a center impermeable to bulk material can be provided in particular within the ring. These designs allow a distribution of the bulk material within the bulk material entry module, which can be adapted to each set requirements. As far as several funnels are present in the cone section, connecting lines for the drying gas can be present between the funnels, around which the bulk material can flow. Such a connecting line can be designed as a triangular roof. With the bulk material level sensor, which is arranged in the bulk material entry module, a uniform throughput of the heat exchanger module can be ensured with a constant residence time in the heat exchanger module. This promotes a uniform cooling effect. An undesirable overfilling or undesired emptying of the bulk material entry module can thus be prevented.

An embodiment according to claim 2, wherein the bulk material entry module is designed as a product buffer, ie as a bulk material buffer, ensures a uniform throughput of the heat exchanger module with a constant residence time in the heat exchanger module. This promotes a uniform cooling effect.

A separate embodiment according to claim 3 may be equipped with a metering device in the connecting conveyor line. At the metering device it can be a rotary valve. The metering device, as far as a bulk material level sensor is provided, are in signal communication with this. In this way, a regulated throughput of the bulk material entry module is possible. Accordingly, a metering device in the conveying direction after the heat exchanger module with the bulk material level sensor can be in signal communication, so that a controlled throughput of the entire cooling device can be realized.

A discharge section of the bulk material entry module can be designed as a simple cone, as a double cone or as a multiple cone with integrated collecting space. A discharge section of the bulk material entry module can also be designed as a cone or funnel with an annular funnel exit. In the embodiment as a double or multiple cone, a plurality of hoppers arranged one inside the other may be present, so that a plurality of nested annular, in particular annular, outlet or exit openings for the bulk material result. In the case of the design with a collecting space, a single funnel or a plurality of funnels can open into it.

An embodiment according to claim 4 allows a compact arrangement of the cooling device in a plant environment.

An embodiment according to claim 5 is particularly compact. Drying and cooling can take place in one and the same module housing. The bulk material discharge module can also be designed as a section of the common module housing of the cooling device. As a rule, the bulk material discharge module is designed as a section of the housing of the heat exchanger module.

A hopper assembly according to claim 6 allows a cone section with advantageously low height at a given distribution performance. Another gas supply line according to claim 7 allows a further drying of the bulk material when passing it through the heat exchanger module. The further gas supply line can communicate with a cooling unit for the drying gas. This increases the drying performance of the drying gas, so that it still acts drying even when the bulk material has already cooled in the heat exchanger module. In addition, the cooling unit can prevent the cooled bulk material is undesirable warmed up by the drying gas.

A common gas source according to claim 8 leads to an efficient drying gas supply.

At least one throttle unit according to claim 9 allows a guided gas quantity specification in the at least one gas supply line. In the case of a plurality of gas supply lines, it is also possible with the aid of the at least one throttle unit or with the aid of a plurality of throttling units to predefine a distribution of the drying gas to the various gas supply lines.

The object mentioned above is also achieved by a method according to claim 10.

The advantages of this method correspond to those already explained above with reference to the cooling device according to the invention were. It can be provided before drying dry bulk with a residual moisture content of not more than 3%. The residual moisture of the bulk material before drying can amount to a maximum of 1% or even a maximum of 0.5%. A drying time or a residence time of the bulk material in a drying module may be greater than 2 minutes, may be greater than 3 minutes, may be greater than 5 minutes, may be greater than 10 minutes, may be greater than 20 minutes, may be 30 minutes and may be greater than 30 minutes. The drying time is that time in which the drying gas acts on the bulk material, that is, the bulk material is subjected to the drying gas. The method can be used using the cooling device according to the invention. In this case, the bulk material entry module of the cooling device according to the invention is the drying module. The residence time may be such that the moisture content of the bulk material during drying is reduced by more than 300 ppm, by more than 500 ppm or by more than 1,000 ppm. The bulk material may be tempered during drying. The drying temperature may be in the range between 50 ° C and 180 ° C, may be in the range between 80 ° C and 160 ° C and may in particular be in the range between 80 ° C and 130 ° C, z. B. at 100 ° C, are. Drying can take place by a diffusion process in which the bulk material is dried in the area of the particle surfaces. By additionally passing drying gas through the bulk material during cooling, the drying performance can be further increased. Preferably, cooled drying gas is used during cooling.

A Gegenstromfiihrung according to claim 11 leads to a particularly efficient drying of the bulk material.

A view of the bulk material according to claim 12 leads to a treated bulk material as a result of the process with a predetermined particle size distribution without fraction with undesirably small bulk material or dust particles. In addition, bulk material views can prolong the service life lead, as already explained above in connection with the device.

Figur 1

schematisch in einer Übersicht eine Vorrichtung zum Kühlen von Schüttgut, wobei ein Schüttgut-Eintragsmodul und ein Schüttgut-Wärmetauschermodul als separate Einrichtungen ausgeführt sind, die über eine Förderleitung miteinander ver- bunden sind;

Figur 1a

einen Austragsabschnitt des Eintragsmoduls, der alternativ zu einem in der Figur 1 dargestellten Austragsabschnitt zum Einsatz kommen kann;

Figur 1b

einen Austragsabschnitt des Eintragsmoduls, der alternativ zu dem in der Figur 1 dargestellten Austragsabschnitt zum Ein- satz kommen kann;

Figur 2

eine weitere Ausführung einer Vorrichtung zum Kühlen von Schüttgut, wobei ein Schüttgut-Eintragsmodul und ein Schüttgut-Wärmetauschermodul als Abschnitte eines gemein- samen Modulgehäuses der Kühlvorrichtung ausgeführt sind, wobei das Schüttgut-Eintragsmodul, das Schüttgut- Wärmetauschermodul sowie ein Schüttgut-Austragsmodul schematisch in einem Längsschnitt dargestellt sind;

Figur 3

eine weitere Ausführung eines Schüttgut-Eintragsmoduls für die Ausgestaltung nach Figur 2;

Fig. 3a

eine Aufsicht auf einen Konusabschnitt des Schüttgut- Eintragsmoduls nach Fig. 3;

Figur 4

schematisch einen Längsschnitt durch einen Konusabschnitt eines Schüttgut-Eintragsmoduls nach Art desjenigen der Fi- gur 2;

Figur 5

eine Aufsicht auf den Konusabschnitt gemäß Blickrichtung 1 in Figur 4; und

Figur 6

in einer zu Figur 5 ähnlichen Darstellung eine Aufsicht auf eine weitere Ausführung eines Konusabschnittes für eine wei- tere Variante eines Schüttgut-Eintragsmoduls.

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

FIG. 1

schematically an overview of a device for cooling bulk material, wherein a bulk material entry module and a bulk material heat exchanger module are designed as separate devices that are connected to one another via a delivery line;

FIG. 1a

a discharge section of the entry module that is alternative to one in the FIG. 1 shown discharge section can be used;

FIG. 1b

a discharge section of the entry module, which is alternative to that in the FIG. 1 shown discharge section can be used;

FIG. 2

a further embodiment of a device for cooling bulk material, wherein a bulk material entry module and a bulk material heat exchanger module are designed as sections of a common module housing of the cooling device, wherein the bulk material entry module, the bulk material heat exchanger module and a bulk material discharge module schematically in a Longitudinal section are shown;

FIG. 3

a further embodiment of a bulk material entry module for the embodiment according to FIG. 2 ;

Fig. 3a

a plan view of a cone section of the bulk material entry module Fig. 3 ;

FIG. 4

3 shows a schematic longitudinal section through a cone section of a bulk material entry module in the manner of that of FIG. 2;

FIG. 5

a view of the cone section according to viewing direction 1 in FIG. 4 ; and

FIG. 6

in one too FIG. 5 a similar view of a further embodiment of a cone section for a further variant of a bulk material entry module.

FIG. 1 shows an embodiment of a device 1 for cooling bulk material. The cooling device 1 has a bulk material entry module 2, which is designed as a product buffer container. The entry module 2 represents a predrying container. A discharge section 3 of the bulk material entry module 2 tapers conically. In the discharge section 3, a bulk material distribution cone 4 is arranged centrally and fixed in a manner not shown on a container wall of the bulk material insert module. The bulk material distribution cone 4 runs upwards, ie counter to a bulk material conveying direction 5, pointed. In other words, the bulk material distribution cone 4 expands in the conveying direction 5. In the conveying direction 5 directly below the bulk material distribution cone 4 ends a vertically extending feed section 6 of an otherwise horizontally extending gas supply line 7 for the introduction of a drying gas for the conveyed into the bulk material entry module bulk material. In the gas supply line 7, a fan 8 is arranged, which is driven by a motor 9. Instead of the blower 8 and a compressed air generator can be used. A sucked from the fan 8 from the environment amount of the drying gas can be set variably via an adjustable throttle (not shown) or via a speed control of the blower 8. The throttle is arranged in the gas supply line 7 in the flow path to the blower 8. At a suction end of the gas supply line 7, a filter 10 for the input cleaning of the supplied via the gas supply line 7 in the bulk material entry module 2 drying gas is arranged.

The latter connects the bulk material infeed module 2 with a bulk material heat exchanger module 12 of the cooling device 1. In the bulk material conveying line 11 is a rotary valve 13 as a bulk material metering device and for pressure sealing arranged. A cellular wheel 14 of the rotary valve 13 is driven by a motor 15.

The structure of the bulk material heat exchanger module is known in principle from the DE 10 2004 041 375 A1 and the DE 10 2007 027 967 A1 , Through this leads a plurality of heat exchanger tubes 17 for conveying the bulk material to be cooled in the heat exchanger module 12 through the heat exchanger section 16. In the illustrated embodiment, this Durchförderung done by gravimetric flow of the bulk material through the heat exchanger section 16. Miteinander in connection standing spaces 18 between the heat exchanger tubes 17 are available with a schematically illustrated inlet port 19 for introducing a cooling medium and with an outlet nozzle 20 also shown schematically for discharging the cooling medium from the intermediate spaces 18 in fluid communication. The heat exchanger tubes 17 thus represent heat exchanger elements which are in thermal contact with the cooling medium via the intermediate spaces 18. The cooling medium is passed through the heat exchanger section 16 in countercurrent to the bulk material conveying direction 5.

In the conveying direction 5 in front of the heat exchanger section 16, the heat exchanger module 12 has its own bulk material buffer section 21. In these, the conveying line 11 opens. Downstream of the heat exchanger section 16 in the conveying direction 5 is a discharge module of the cooling device 1 in the form of a discharge section 22 of the heat exchanger module 12, which tapers conically in the conveying direction 5, comparable to the discharge section 3 of the entry module 2. The buffer section 21, the heat exchanger section 16 and the discharge section 22 are sections of a common module housing 23 of the heat exchanger module 12.

In the discharge section 22 opens another gas supply line 24 for introducing bulk material drying gas in countercurrent to the conveying direction 5 through the heat exchanger module 12. In the further gas supply line 24 is another blower 25 for Trocknungsgasförderung, which is driven by a motor 26 , Upstream of the blower 25, a condensate separator 27 is arranged in the further gas supply line 24. Once again upstream of the condensate separator 27, a suction cooler 28 designed as a heat exchanger is arranged in the further gas feed line 24. Upstream of the suction cooler 28 is at a suction end of the further gas supply line 24, in turn, a filter 29 for input cleaning of the other gas supply line 24 arranged the heat exchanger module 12 amount of drying gas. Also in the gas supply line 24 may be arranged an adjustable throttle, with which the sucked from the fan 25 from the environment amount of the drying gas can be variably specified.

The discharge section 22 opens into a bulk material discharge line 30. In this, a further rotary feeder 31 is arranged as a discharge metering device, the cell wheel 32 is driven by a further motor 33.

Instead of the rotary valves 13, 31, slides or screw conveyors can in principle also be used as metering devices.

The motors 9, 15, 26, 33 and the suction cooler 28 and a conveyor not shown for the guided through the heat exchanger section 16 cooling medium are controlled by a central control device, not shown. The throttles, not shown in the gas supply lines 7, 24 may alternatively also be designed as motor-adjustable valves or flaps, in particular as control valves or control valves, and may then also be controlled by the central control device.

A treatment method for bulk material runs in the cooling device 1 as follows: First, the bulk material is filled into the entry module 2 or accumulated by slowing down the feeder speed at the rotary valve 31. By means of the passage of the drying gas, the bulk material is dried in countercurrent to the conveying direction 5 by the entry module 2. The drying gas coming from the feed section 6, is initially deflected radially outwards by the bulk material distribution cone 4 (cf., directional arrow 34), so that the bulk material flowing past the distribution cone 4 in the discharge section 3 of the entry module 2 is uniformly and completely charged with the drying gas. After drying in the passage through the entry module 2, the bulk material is conveyed by means of the rotary valve 13 toward the heat exchanger module 12. There, the bulk material is cooled in the heat exchanger section 16. The cooling takes place mainly by contact of the bulk material with the tube walls of the heat exchanger tubes 17, which in turn are cooled by the cooling medium. At the same time, the bulk material is further dried in the heat exchanger module 12 with the aid of the cooled drying gas, which is supplied via the further gas feed line 24, in countercurrent to the conveying direction 5.

In the various bulk material buffer sections internals can be provided, which bring about a relative movement of the bulk material particles with each other. Such internals may be, for example, perforated plates, gratings or other designs designed to effect such rearrangement by relative movement of the bulk material particles with each other.

As bulk material, fertilizers, salts, biomass or sugar can be used.

• ASS-Ammonium-Sulphat-Salpeter
• Harnstoff (UREA) und harnstoffbasierte Düngemittel
• Düngemittel, die auf Ammonium-Salzen beruhen, insbesondere AN (Ammonium-Nitrat)-Dünger und AS (Ammoniumsulfat)-Dünger
• NPK (Stickstoff Phosphor Kalium)-Dünger oder NP (Stickstoff Phosphor)-Dünger
• CAN-Dünger (Calzium-Ammonium-Nitrat)
• Dünger auf Phosphatbasis
• SSP (Single Super Phosphat)
• MAP (Monoammonium Phosphat)
• DAP (Diammonium Phosphat)
• TSP (Triple Super Phosphat)
• Pottasche und Gemische derselben
• Gemische aus den oben genannten Düngemitteln
• organischer Dünger

As fertilizer can be used in particular:

• ASS ammonium sulphate saltpeter
• Urea (UREA) and urea-based fertilizers
• Fertilizers based on ammonium salts, in particular AN (ammonium nitrate) fertilizer and AS (ammonium sulfate) fertilizer
• NPK (Nitrogen Phosphorus Potassium) fertilizer or NP (Nitrogen Phosphorus) fertilizer
• CAN fertilizer (calcium ammonium nitrate)
• Phosphate-based fertilizer
• SSP (Single Super Phosphate)
• MAP (monoammonium phosphate)
• DAP (Diammonium phosphate)
• TSP (Triple Super Phosphate)
• Potash and mixtures thereof
• Mixtures of the aforesaid fertilizers
• organic fertilizer

These fertilizers may also be coated or it may be added to these fertilizers, a flow aid.

The bulk material may be in the form of crystals, pellets or prills.

The bulk material is fed to the entry module 2 with a residual moisture content of not more than 3%. The residual moisture of the bulk material provided may alternatively not be greater than 1% or not greater than 0.5%. A drying residence time of the bulk material in the infeed module 2 is greater than one minute and may be greater than two minutes, may be greater than three minutes, may be greater than five minutes, may be greater than ten minutes, may be greater than twenty minutes, can be 30 minutes and can be greater than 30 minutes.

The drying of the bulk material in the entry module 2 before the heat exchange in the heat exchanger module 12 prevents caking of bulk material in the heat exchanger module 12. As a drying gas, air or nitrogen can be used.

As an alternative to the heat exchanger tubes 17, heat exchanger plates may also be arranged in the heat exchanger section 16, as in the example of FIG FIG. 2 of the EP 0 444 338 B1 shown. As heat exchanger elements can also be used horizontally and / or transversely to the conveying direction 5 through the heat exchanger section 16 extending and traversed by the cooling medium pipes. These tubes may have different cross-sectional shapes and, for example, have an oval or quadrangular cross-section.

FIGS. 1a and 1b show two alternatives of discharge sections 35, 36, which can be used instead of the discharge section 3 in the bulk material entry module 2. Components which correspond to those described above with reference to FIG. 1 have already been explained, bear the same reference numbers and will not be explained again in detail.

The discharge section 35 after FIG. 1a has a buffer portion 37 of the entry module 2 directly following a first cone portion 38. This has a ring-shaped circumferential cone or funnel 39, which tapers in the conveying direction 5 funnel-shaped towards a circular funnel exit 41 for the bulk material. Connected to the cone section 38 in the bulk material conveying direction 5 is a collecting space section 42, which is likewise conical in shape. In the plenum section 42 opens from the side, the gas supply line. 7 one. The conically tapered collecting chamber section 42 opens into the bulk material conveying line 11.

When using the discharge section 35 to FIG. 1a The drying gas from the gas supply line 7 first flows into an outer annular space 40 in the interior of the collecting space subsection 42 and from there in countercurrent to the bulk material conveying direction 5 through the annular funnel exit 41 in the FIG. 1a upward, ie by annular cone and the other cone portion 38 and subsequently by the buffer portion 37 of the entry module. 2

The discharge section 36 after FIG. 1b is designed as a double cone with two successive cone sections 43, 44. The first cone section 43 in the conveying direction 5 tapers towards a funnel outlet 45. The latter lies within the downstream second cone section 44, which constitutes a collecting space. The second cone section 44 tapers conically towards the bulk material delivery line 11.

During drying of the bulk material, the drying gas flows from the gas supply line 7 first into the second cone section 44, that is, into the collecting space of the embodiment FIG. 1b , Subsequently, the drying gas flows in countercurrent to the bulk material conveying direction 5 through the funnel exit 45 into the cone section 43 and from there into the buffer section 37 of the entry module 2 FIG. 1b ,

The buffer section 37 can also be a bulk goods storage container, for example a storage silo, which is arranged upstream of the discharge section 3. FIG. 2 shows a further embodiment of a cooling device 46. Components which correspond to those which have already been explained above with reference to the figures bear the same reference numerals and will not be discussed again in detail.

In the cooling device 46, a bulk material entry module 47 and the heat exchanger module 12 are sections of a common module housing 48.

Bulk 49 passes from a screening machine 50 via a downcomer 52 and a bulk material entry port 51 in the bulk material entry module 47th

The structure of the bulk material entry module 47 corresponds to that of the buffer section 37 with a downstream cone section 38 of the embodiment FIG. 1a , The circular ring-shaped funnel exit 41 of the annular cone or funnel 39 of the cone section 38 of the bulk material introduction module 47 opens directly into the bulk material buffer section 21 of the bulk material heat exchanger module 12. In this bulk material buffer section 21 of the heat exchanger module 12 opens laterally a gas feed port 55, which in turn communicates with a gas supply line 56 for introducing the drying gas. The gas supply line 56 of the embodiment according to FIG. 2 corresponds to the gas supply line 7 of the embodiment according to FIG. 1 , In the gas supply line 56, a manually operable manual flap 57 is provided as a throttle unit for setting a quantity of gas in the gas supply line 56. Upstream of the hand flap 57, an adjustable aperture 58 is arranged for additional specification of the amount of drying gas. The aperture 58 may also be used as an alternative to the manual flap 57 for setting the amount of drying gas.

The buffer portion 21 has at least one height such that an outer region of the heat exchanger module 12 is just filled with bulk material automatically on the angle of repose. In order to ensure this filling of the outer region of the heat exchanger module 12, the overall height of the buffer section 21 is selected 200 mm to 500 mm larger than this minimum height. The buffer section 21 is constructed so that the heat exchanger module 12 is accessible from above via the lateral inspection openings (not shown) for cleaning and inspection via the buffer section 21.

In addition to the bulk material inlet nozzle 51, a gas suction nozzle 59 is arranged with downstream suction line 60. In the suction line 60, a suction fan 61 is arranged. Before the suction fan 61, a filter may be arranged in the suction line 60 in order to prevent contamination of the suction fan 61.

In the discharge section 22 of the heat exchanger module 12, a roof-shaped bulk material distribution cone 62 is arranged. Directly below the distributor cone 62 opens into the discharge section 22 laterally another gas supply port 63, which communicates with a further gas supply line 64, the function of the further gas supply line 24 in the embodiment according to FIG. 1 equivalent. In the further gas supply line 64, in turn, a manually operable hand flap 65 is arranged. Upstream, on the one hand, the orifice 58 and on the other hand, the hand flap 65, the two supply lines 56 and 64 unite at a distribution point 66. Upstream of the distribution point 66, a main gas supply line 67 is arranged. The two gas supply lines 56, 64 are thus fed by a common gas source. In the main gas supply line 67, a fan 68 is disposed upstream of the distribution point 66, the is driven by a motor 69. Upstream of the blower 68, a condensate separator 70 is disposed in the main gas supply line 67. Upstream of this, a suction cooler 71 is disposed in the main gas supply pipe 67. Again upstream of this, a filter 72 for cleaning the sucked drying gas is arranged in the region of a suction end of the main gas supply line 67.

In the buffer section 37 of the bulk material entry module 47, a measuring lance 73 of a filling level transmitter 74 is arranged. These two components constitute a bulk material level sensor for the buffer section 37. The motor 33 of the rotary valve 31 in the bulk material discharge line 30 on the one hand and the fill level transmitter 74 on the other hand are connected to one another via a control loop 75.

A treatment of the bulk material 49 is carried out with the cooling device 46 as follows: The bulk material 49 passes through the screening machine 50 and the bulk material entry port 51 in the bulk material-entry module 47. The bulk material 49 then flows through the buffer section 37 and the cone section 38 and through the annular Funnel exit 41 into the bulk material buffer section 21 of the heat exchanger module 12. During the path between the entry port 51 and the buffer section 21, the bulk material is dried by means of the passage of the drying gas through the gas supply line 56. The drying gas enters the bulk material buffer section 21 (see directional arrow 76) of the heat exchanger module 12 via the gas feed port 55, which simultaneously constitutes a collecting space for the drying gas. From there, the drying gas (see directional arrow 77) flows through the funnel exit 41 of the circular, circulating cone 39 of the cone section 38 and further over the buffer section 37. The drying gas is conveyed via the gas suction connection 59 and sucked the suction line 60 (see arrows). Like in the FIG. 2 indicated by dashed lines at 87, the drying gas can be recycled. The suction line 60 is then in fluid communication with the main gas supply line 67. A separator cyclone and / or a dust filter for separating dust particles and corresponding cleaning of the drying gas can then be arranged between the gas extraction nozzle 59 and the suction blower 61.

The thus dried or predried bulk material is then cooled in the heat exchanger module 12 while flowing through the heat exchange tubes 17 of the heat exchanger section 16. During the flow of the bulk material through the heat exchanger section 16 on the one hand and by the subsequent discharge section 22 on the other hand, the bulk material is further dried over the further drying gas, which is supplied via the further gas supply line 64. This further drying gas flows into the interior of the discharge section 22 via the gas feed port 63. The distributor cone 62 ensures that the bulk material, which is conveyed through the discharge section 22, is evened out and is subjected as homogeneously as possible to the further drying gas (compare directional arrow 78).

In front of the annular funnel 39, a static sieve may be arranged as an agglomerate catcher in the entry module buffer section 37. Such an agglomerate catcher can also be arranged in the buffer section 21.

Via the fill level transmitter 74, the control loop 75 and the motor 33 for the rotary valve 31, it is ensured that the fill level in the entry module buffer section 37 is in the range of a predetermined fill level bandwidth remains. In order to detect and avoid overfilling or unintentional emptying of the buffer section 37, a maximum permissible fill level and a minimum permissible fill level can also be interrogated via the fill level transmitter 74. This monitoring of a maximum allowable level and a minimum allowable level can alternatively be done by two separate level indicator instead of Füllstandsstransmitters 74.

FIG. 3 shows a further variant of a bulk material entry module 79, which instead of the bulk material entry module 47 after FIG. 2 can be used. Components which correspond to those already explained above with reference to the figures bear the same reference numerals and will not be discussed again in detail.

Subsequent to the bulk material inlet nozzle in the bulk material conveying direction 5, a spreading plate 80 is present at the bulk material injection module 79. This has a diameter which is slightly larger than that of the inlet nozzle 51. The spreading plate 80 has an impact wall 81 which extends from a center of the spreading plate 80, starting conically sloping outwards. The scattering plate 80 is held in a manner not shown relative to the entry port 51 in position. The scattering plate 80 may stand in the operation of the cooling device with the entry module 79 or, as in the FIG. 3 indicated by a directional arrow 82 to one in the FIG. 3 Rotate vertical axis 83 driven by a motor, not shown, which extends through the center of the spreading plate 80.

Downstream of the buffer section 37 of the entry module 79 is a cone section 83 with a total of two cones or funnels 84, 85 arranged concentrically in one another in the form of a circle. The funnels 84, 85 taper in the conveying direction 5 towards concentric nested, annular circumferential funnel exit 41, 86 (see Fig. 3a ) and terminate in the bulk material buffer section 21 of the heat exchanger module 12. Laterally offset to the central bulk material entry port 51 is in a top wall 88 of the module housing 48 of the execution to FIG. 3 a drying gas outlet 89 arranged. This communicates with a suction line 90, whose function of that of the suction line 60 in the execution after FIG. 2 equivalent. In the suction line 90, the suction fan 61 is arranged.

That in the execution after FIG. 3 Bulk material 49 supplied via the inlet connection 51 is distributed via the spreading plate 80 over the entire cross section of the buffer section 37 of the bulk material introduction module 79. Subsequently, the bulk material 49 flows through the two cones or funnels 84, 85 and after passing through their funnel exits 41, 86 in the bulk material buffer section 21 of the heat exchanger module 12. During this conveying path, the bulk material 49 by means of the passage of the gas via the supply line 56 dried drying gas dried. The drying gas flowing into the interior of the bulk material buffer section 21 via the gas supply connection 55 flows through the funnel exits 41, 86 into the funnels 84, 85 and from there into the entry module buffer section 37. Here, too, the bulk material buffer section 21 of the heat exchanger module has 12 thus the function of a collecting space for the drying gas. The drying gas leaves the entry module buffer section 37 via the drying gas outlet port 89 and the suction line 90. In the case of a circulatory system, the suction line 90 in turn with the gas supply line 56 or with a main gas supply line in the manner of the main gas Feed line 67 after FIG. 2 in fluid communication.

The inner annular cone or funnel 86 can be connected to the gas supply port 55 via its own, in the Fig. 3 Be connected supply line not shown. This ensures that the drying gas also flows through the inner annular cone 86.

Based on FIGS. 4 to 6 further embodiments of cone sections are explained, which can be used instead of the cone sections 38 and 83. Components which correspond to those already explained above with reference to the figures bear the same reference numerals and will not be discussed again in detail.

A cone section 91 after the FIGS. 4 and 5 has at least two slot funnels 92, 93 with slot-shaped or longitudinal outlet openings 94, which in the FIG. 5 are shown in a plan. These outlet openings 94 serve on the one hand for the passage of the bulk material in the conveying direction 5 and on the other hand for the passage of the drying gas in the opposite direction.

The function of the cone section 91 otherwise corresponds to the function of the cone section 38 FIG. 2 ,

A cone section 95 after FIG. 6 has an outer, circular peripheral cone ring 96, which in the conveying direction 5, in the FIG. 6 extends vertically from above through the plane of the drawing, inwardly towards a rectangular circumferential outlet opening 97 drops. The exit opening 97 bounded inwardly a central, pyramid-shaped counter-cone 98, which is in the opposite direction to the conveying direction 5 to the center tapered towards whose guide walls 99 so also fall to the exit opening 97 out.

The configuration of the cone section 95 according to FIG. 6 favors a well-distributed transfer of the bulk material from the cone section 95 in the downstream buffer section 21 and thus leads to a good drying performance by the in the opposite direction to the conveying direction 5 through the outlet opening 97 flowing drying gas.

Instead of the rectangular exit opening 97, a circular exit opening may also be present. In this case, the cone ring 96 and the counter cone 98 can also be designed as rotationally symmetrical cones.

The amounts of gas in the various supply lines can also be specified by means of a control circuit, not shown, depending on the drying capacity to be achieved. This can be done, for example, depending on the degree of moisture of the supplied bulk material and / or depending on the supplied bulk flow, the bulk material temperature, the type of bulk material or other parameters.

Instead of an entry in the discharge section 3, in the discharge section 22, in the discharge sections 35, 36 and in the buffer section 21 via a single gas supply line, entry via a plurality of such gas supply lines is also possible. These can lead into the discharge section or into the corresponding collection space at different heights.

About extraction with the help of the gas extraction nozzle 59 in execution after FIG. 2 or with the aid of the gas outlet stub 89 FIG. 3 can be a view of the bulk material during drying accomplish. In the FIG. 3 are separated from the other bulk material 49 to be separated during the viewing dust particles with 100. These dust particles are removed via the suction line 90 and can later be separated from the drying gas via a separator cyclone and / or a filter.

For drying the drying gas prior to its introduction into the entry module and / or the heat exchanger module, an absorption dryer can be used.

Claims (12)

1. Device (1; 46) for cooling bulk material (49) comprising

   - a bulk material entry module (2; 47; 79),

   - a bulk material heat exchanger module (12) arranged downstream of the bulk material entry module (2) in the conveying path of the bulk material with a plurality of heat exchanger elements (17) which are in thermal contact with a cooling medium,

   - a bulk material discharge module (22),

   - wherein a gas supply line (7; 56) for introducing a drying gas opens into the bulk material entry module (2; 47; 79), wherein the bulk material entry module (2; 47; 79) is configured such that the dwelling time of the bulk material (49) in the bulk material entry module (2; 47; 79) is greater than 1 min,

   - wherein the bulk material entry module (2; 47; 79) has a conical section (38; 43, 44; 83; 91; 95) in which the bulk material (49) is guided along at least one funnel tapering in conveying direction and/or an angular cone (39; 43; 84, 85; 92, 93; 96, 98) with a round and/or rectangular outlet opening which leads to a collecting chamber (42; 44; 21) of the bulk material entry module (2; 47; 79),

   - wherein the gas supply line (7; 56) opens from the outside directly into the collecting chamber (42; 44; 21) and prevents or completely avoids any unwanted caking of the bulk material particularly on the heat exchanger elements,

   - wherein in the bulk material entry module (47) a bulk material filling level sensor (73, 74) is arranged.
2. Device according to claim 1, characterised in that the bulk material entry module (2; 47; 79) is configured as a product buffer.
3. Device according to one of claims 1 to 2, characterised in that the bulk material entry module (2) and the heat exchanger module (12) are configured as separate devices which are connected together via a conveying line (11).
4. Device according to claim 3, characterised in that the bulk material entry module (2) is formed in the outlet section (3) of an upstream bulk material storage container.
5. Device according to one of claims 1 to 2, characterised in that the bulk material entry module (47; 79) and the bulk material heat exchanger module (12) are configured as sections of a common module housing (23; 48) of the cooling device (46).
6. Device according to claim 5, characterised in that in the conical section (38; 83; 91) a plurality of adjacent and/or concentrically arranged funnels (39; 84, 85; 92, 93) are provided.
7. Device according to one of claims 1 to 6, characterised in that a further gas supply line (24; 64) for introducing drying gas opens into the bulk material discharge module (22).
8. Device according to claim 7, characterised in that the two gas supply lines (56, 64) are supplied by a common gas source.
9. Device according to one of claims 1 to 8, characterised by at least one constriction unit (57, 58, 65) for specifying a gas amount in the at least one gas supply line (7, 24; 56, 64).
10. Method for processing bulk material comprising the following steps:

    - drying the bulk material (49) by passing a drying gas through the bulk material (49) in the conveying path of the bulk material upstream of a bulk material heat exchanger module (12) with a drying time of the bulk material of more than 1 min.,

    - cooling the bulk material (49) after drying by contacting the bulk material (49) with heat exchanger elements (17) of the bulk material heat exchanger module (12),

    - wherein the gas for drying the bulk material (49) is introduced via a gas supply line (7; 56) from the outside directly into a bulk material entry module (2; 47; 79),

    - wherein the filling level of the bulk material in the bulk material entry module (47) is measured using a bulk material filling level sensor,

    - wherein the drying gas is introduced into the bulk material entry module so that any undesirable caking of bulk material particularly onto the heat exchanger elements is reduced or avoided altogether,

    - wherein gas for passing drying gas through the bulk material (49) is introduced during cooling via a further gas supply line (24; 64) which opens into the bulk material discharge module (22).
11. Method according to claim 10, characterised in that drying gas is guided in counterflow against a conveying direction (5) of the bulk material (49) during drying.
12. Method according to one of claims 10 to 11, characterised by sifting the bulk material (49) during the drying.

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