EP1929888B1 - Rotary drier for the tobacco processing industry - Google Patents

Description

The invention relates to a method for drying tobacco in a substantially horizontally oriented trained as a drum dryer drying device of the tobacco industry, wherein the drum dryer is rotatably mounted and is set in rotation and wherein tobacco is conveyed via an entry in an interior of the drum dryer and the dried tobacco is conveyed away via a discharge from the interior. Moreover, the invention relates to a drying device of the tobacco-processing industry for drying tobacco, wherein the drying device is designed as a drum dryer, with an entry, is conveyed through the tobacco in an interior of the drum dryer and a discharge, via which the tobacco from the interior the drum dryer is conveyed away, wherein the drum dryer is rotatably mounted. Moreover, the invention relates to a plant of the tobacco processing industry.

In DE 26 38 446 A1 is a tobacco dryer with a tobacco in the passage-promoting drying drum described which has a tobacco feed, a tobacco discharge and heating means and a control means for the heating means. As a heating means Wandbeheizungen be used in which the heating acts as a vapor in a closed tube system in the region of the drum wall on the tobacco. The steam is supplied as a kind of fixed or variable basic heating mostly from the drum output forth.

Under designation "KLK" a drum dryer of the patent applicant is known. This tumble dryer heats wall liners and vanes inside the drum with steam. Depending on the drying process, starting temperatures of the tobacco are reached from 60 ° to 80 ° Celsius. In the drum dryers used, a constant initial moisture content of the dried tobacco is achieved in accordance with a predetermined specification.

WO 97/27766 discloses a method and apparatus for drying, cooling and rearranging strip tobacco. Here, a tobacco dryer with several heating zones is provided, in which the tobacco is exposed to high pressure air. The air is recirculated independently in the heating zones, thereby reducing the moisture content of the tobacco. To convey the tobacco through the heating zones, a vibrating conveyor is provided which conveys the tobacco horizontally through the heating zone.

Further disclosed US-A-2002/0029491 a method and apparatus for drying wet organic material, especially for drying fodder plants. In this case, the moist organic material is introduced into a rotating drum in which various drying zones are formed. For the drying process, the dryer is operated in countercurrent process. Since heating fans are provided between the individual zones in order to heat the air, a heat medium is applied to the zones arranged one behind the other in the material flow.

The object of the present invention is to make the drying of tobacco in a tumble dryer more variable, it being possible to make the start-up shot, i. to reduce the unusable amount when starting a drum dryer, the design effort for the drum dryer should be as low as possible.

The object is achieved by a method for drying tobacco in a substantially horizontally oriented designed as a drum dryer drying device of the tobacco industry, wherein the drum dryer is rotatably mounted and is rotated and wherein tobacco is promoted via an entry in an interior of the drum dryer and the dried tobacco is conveyed away via a discharge from the interior, which is further developed by the fact that in the drum dryer at least two successively arranged in the tobacco flow zones are acted upon with a heat medium independently, the zones of the drum dryer an annular heating module with plate-shaped and in the manner of Polygons arranged inner walls, wherein the inner walls are formed with a hollow chamber, and wherein the heating modules enclose the interior of the drum dryer.

Characterized in that several drying zones are provided for the cut tobacco in the interior, it is possible during the promotion of the tobacco from the entry to the discharge to heat and dry them, wherein the heating of each zone is done individually with a separately tempered heat medium. This is achieved individually to provide a certain temperature in each conveyor zone or drying zone. In this case, the transport path from the entry to the discharge is subdivided into a plurality of (conveying) segment areas or conveying areas, which are respectively heated individually with a heating medium.

Characterized in that along the conveyor areas or the tobacco flow, a predetermined temperature profile is formed from the entry to the discharge, the drying device can be used variably. Along the transport path with the conveyor regions, which are heated differently, in this case corresponding heating modules are arranged one behind the other, wherein the heating modules are annular, so that the arrangement of several heating modules surrounds or surrounds the heated interior of the drying device.

In a preferred embodiment, it is also possible that a zone or a drum segment or a corresponding (heating) module is acted upon by a cooling medium, so that a cooling process within the dryer, preferably at the output or discharge, is made possible.

In the context of the invention, a substantially horizontal orientation of the drying device is also understood to mean a slightly falling arrangement of the drying device with a slope of 1 ° to 10 °.

Furthermore, in order to heat or cool each zone separately from the adjacent zones, it is provided that the heating medium and / or the cooling medium is supplied to each zone via a respective supply line.

It is further provided that the heat medium and / or the cooling medium is discharged from each zone via a respective discharge line.

Moreover, it is advantageous if a predetermined zone temperature is set in each zone on the inner walls and / or the blading. The fact that the walls and the blading are modular or segmented formed in each conveyor zone, the tobacco masses, such as leaf cut, rib section and pipe tobaccos and Burley strips are dried accordingly gently, with a uniform final moisture content is achieved.

The individual, targeted heating of the zones, it is possible that the desired final moisture is achieved, the fluctuation ranges or standard deviation of the moisture is less than with the conventional drying process in a drum dryer. The incidence of leaf incision is typically between 21% to 22% and in the case of rib section 34% to 38%, which, with a corresponding retention time of 3 to 4 minutes (for rib section) or 7 minutes (leaf section) to a starting moisture content of 12 to 15%. is dried.

For heating the inner walls or the blading steam is used in each case, so that the blades are heated, for example, up to a temperature of about 180 ° C. in this connection is further provided that corresponding control devices or control devices are provided so that a desired or predetermined temperature is set in a zone or a conveyor segment in the drum dryer.

In the context of the invention it is possible to heat the zones individually as well.

Characterized in that independently of each other different heat zones Z1, Z2, Z3 are provided in the interior of the drying device or the drum dryer through which the tobacco is conveyed from the entry to the discharge, it is possible to dry even smaller amounts of tobacco to a desired final moisture.

Further, when starting the drying device of the starting shot is significantly reduced by setting a certain temperature profile of the heat zones Z1, Z2, Z3 or cooling zones along the conveyor line from the entry to the discharge, since it is possible, the heat zones Z1, Z2, Z3, for example to set a time circuit to a desired temperature profile. The tobacco of the drum dryer is dried accordingly during its promotion.

The object is further achieved by a drying device of the tobacco-processing industry, which is oriented or arranged substantially horizontally for drying tobacco, wherein the drying device is designed as a drum dryer, with an entry, is conveyed on the tobacco in an interior of the drum dryer and with a discharge over the the dried tobacco material is conveyed out of the interior of the drum dryer, wherein the drum dryer is rotatably mounted, which is characterized in that the drum dryer in the interior at least two in the tobacco flow arranged in succession zones, which are each acted upon by a heat medium independently or are, wherein the zones of the drum dryer having an annular heating module with plate-shaped inner walls, wherein the inner walls are arranged in the manner of a polygon, wherein the inner walls are formed with a hollow chamber, and wherein the heating modules enclose the interior of the drum dryer.

Along the conveyor line thus at least two zones can be acted upon with a heat medium, whereby the heat zones are heated differently with a certain temperature or can be heated. Steam or electrical energy can be used as the corresponding heat medium.

In the context of the invention, a corresponding cooling medium is understood as the heat medium, so that a cooling zone, preferably following drying zones, is formed in the drying apparatus. This makes it possible that the cooling process of tobacco material with a desired final moisture after the drying process is already cooled in the drum dryer. In this case, the cooling process is carried out in particular in the last transport zone or conveying zone of the drying device, wherein, for example, water is used as the (cooling) medium for this purpose.

In order to form differently heated zones in the drying device, it is further provided that the (heat) zones be formed by individually heated and controllable or controllable heating modules. Characterized in that heating modules or cooling modules along the conveyor line (from the entry to the discharge) are arranged one behind the other like a module, a simple construction of the drum is made possible because the heating modules of the construction correspond to each other, so that the walls or blading along the drying section are segmented or are segmented.

According to a preferred embodiment, it is further provided that a supply line for a heat medium and / or a drain line for a heat medium are provided for each zone. In this way, for example, steam can be specifically conveyed to an interior segment or a heating module, so that the inner walls and blading of the annular heating module are heated to a predetermined temperature. About the drain lines, the corresponding condensate of the supplied heat medium is derived from the heating module.

For this purpose, it is provided that in each zone, the inner walls and / or blading are heated by means of the heat medium or can be heated.

According to the invention, the drying device is designed as a drum dryer. Advantageously, in this case the supply line and / or the discharge line are arranged substantially longitudinally parallel to the axis of rotation of the drum dryer.

In order to achieve a good and effective drying of the tobacco in the interior, it is further provided that the supply line and / or the drain line are arranged outside the interior. Here, advantageously, the supply line and / or the drain line are arranged in the intermediate space between the walls and the outer wall of the drum.

Preferably, the wall and / or the blading are further connected by means of supply lines to the supply line and / or the drain line, wherein in a preferred embodiment, the supply lines are arranged in the circumferential direction of the drum.

For a different heating of the heating modules or the conveyor zones, a heating or cooling circuit is further provided according to each zone of the drying device. In addition, a control device for controlling the temperature of the zone or a control device for controlling the temperature of the zone is advantageously provided for at least one zone.

In addition, a heat supply device or unit is provided for at least one zone or drying zone of the drying device, so that the zones can be heated individually.

Furthermore, the object is achieved by a plant of the tobacco-processing industry, which is formed with a corresponding drying device or a drum dryer. To avoid repetition, reference is expressly made to the preceding comments on the drying device.

Fig. 1

eine perspektivische Ansicht eines Trommeltrockners der Tabak verarbeitenden Industrie;

Fig. 2

eine perspektivische Ansicht der Heizmodule des Trommeltrockners ohne Außenwandung des Trommeltrockners und

Fig. 3

ein Heizmodul eines Trommeltrockners in einer perspektivischen Ansicht.

The invention will now be described by way of example without limitation of the general inventive concept using an exemplary embodiment with reference to the accompanying schematic drawings, which are expressly referred to in the rest with respect to the disclosure of all unspecified in the text details of the invention. Show it:

Fig. 1

a perspective view of a drum dryer of the tobacco processing industry;

Fig. 2

a perspective view of the heating modules of the drum dryer without outer wall of the drum dryer and

Fig. 3

a heating module of a drum dryer in a perspective view.

In the following figures, the same or similar elements or corresponding parts are designated by the same reference numerals, so that a corresponding renewed idea is disregarded.

Fig. 1 shows a drum dryer 10 in a perspective view. The drum dryer 10 is surrounded by a casing and has an entry (not shown here) and a discharge (not shown here). The drum dryer 10 is rotatably mounted on rollers 11 which are arranged on a frame 12 at the two ends of the drum dryer 10.

Characterized in that the rollers 11 are rotated by a motor in rotation, and the drum dryer 10 is set during the drying process in rotation. At the same time, via the entry at one end of the tumble dryer 10, tobacco material, for example leaf cut or rib cut, is introduced into the interior 14 of the tumble dryer 10 and conveyed under continuous rotation of the tumble dryer 10 for discharge. Typically, the tumble dryer 10 has a length of about 12 meters and is rotated at 8 to 20 revolutions per minute.

Fig. 2 shows the interior of the drum dryer 10 (without representation of the outer jacket) formed heating modules 20.1 to 20.6, which are arranged one behind the other in the conveying direction or along the axis of rotation of the tumble dryer 10. The ring-shaped heating modules 20.1 to 20.6 are designed in the manner of a drum or cable drum and enclose the interior 14, through which the tobacco is promoted.

The heating modules 20.1 to 20.6 each have conduits 21 which are arranged evenly along the axis of rotation parallel to the axis of rotation of the drum dryer 10 between two side walls over the circumference of the respective heating segment 20.1 to 20.6.

Via the conduits 21 of the heating modules 20.1 to 20.6, a heat medium is conveyed to a respective heating module 20.1 to 20.6 by the combination with the pipes of other heating modules and a corresponding connection or disconnection. About another conduit in combination with other pipes of other adjacent heating modules, a discharge line is formed.

Thus, each heating module 20.1 to 20.6 individually a heat medium at a predetermined temperature supplied independently of the other heating modules, so that the walls and the blading of a heating module in the interior 14 are heated to a predetermined temperature.

When assembling the drum dryer 10, the heating modules 20.1 to 20.6 are connected to each other, wherein the conduits 21 of the heating modules 20.1 to 20.6 and are connected to each other by a corresponding circuit of the pipes 21.

For example, steam is introduced via an input E1 to the heating module 20.1, so that the heating module 20.1 and the heating module 20.2 are heated simultaneously and thus a first heat zone Z1 is formed. Via an output A1, the heat medium condensed in the heating modules 20.1 and 20.2, which has been supplied to the heating module 20.1 and 20.2, is correspondingly discharged again. The pipes 21 of the adjacent heating module 20.3, the are co-linear with the conduits 21 of the outer heating modules 20.1 and 20.2 are arranged, via which the heat medium supplied (input E1) and is discharged (output A1) are switched off accordingly.

About the input at the E2 supplied heat medium (eg steam) is passed through the corresponding pipes 21 of the heating modules 20.1 and 20.2 to the heating modules 20.3 and 20.4, so that the heat medium walls and blading of the heating modules 20.3 and 20.4 to a different temperature than the walls and Blades of the heating modules 20.1 and 20.2 heated. As a result, a second heat zone Z2 is formed. Via the output A2, the vapor condensed in the heating modules 20.3 and 20.4 is led away from the drum 10.

To the heating modules 20.1. to provide 20.6 with a heat medium, a distributor unit or supply device V is provided on the front side of the drum 10, are connected to the corresponding heat sources. In addition, the condensates or the cooled heat medium are derived from the heating modules 20.1 to 20.6 at the distribution unit V.

The tubes 21 connected to the inputs E1, E2, E3 and to the outputs A1, A2, A3 rotate with the drum dryer 10 during operation. Just as the Heizmodulpaare 20.1, 20.2 and 20.3 and 20.4, the other heating modules 20.5 and 20.6 are also heated in a corresponding manner, so that it according to the in FIG. 2 shown heating modules 20.1 to 20.6 is possible to form three different heat zones Z1, Z2, Z3 within the drum dryer 10, since a heat zone is formed by two heating modules.

Accordingly, via a further input E3 (see. Fig. 3 ) the heating modules 20.5 and 20.6 supplied through the corresponding pipes 21 of the heating modules 20.1 to 20.4 heat the module 20.3. Via the exit A3 (cf. Fig. 3 ), the heat medium from the modules 20.5 and 20.6 is derived again.

At the in FIG. 2 illustrated heating modules, it is also possible that the heating modules 20.4 to 20.6 are acted upon from the other side of the drum dryer 10 with a heat medium. In the context of the invention, it is also possible that, instead of a heated medium, for example steam, water for cooling the walls and the blading via the conduit 21 of the heating modules is supplied. For example, water at a temperature of 20 ° C to 50 ° C supplied to a heating module, wherein after receiving energy, the discharged water at the outlet has a temperature of 30 ° C to 60 ° C.

In addition, it is possible by the series connection of the heating modules 20.1 to 20.6, the shutdown of the processing plant, that is, after switching off the drying process, the heating modules 20.1 to 20.6 cool accordingly fast by supplying water. The modular juxtaposition of the heating modules 20.1 to 20.6 and the delay of the walls and the blading is reduced in comparison to the conventional drum dryers, so that can be brought into a waiting state faster by the targeted supply of cold water of the drum dryer.

Fig. 3 shows an example of the heating module 20.1 the structure of the heating modules. The heating module 20.1 has a honeycomb-shaped structure inside, which delimit the interior space 14 by the wall parts 24. The wall parts 24 are pillow-like and flat or flat formed so that the heat medium can be passed through the wall parts 24.

In addition, between each wall part 24, a blade part 25 is arranged, which point with a radial component to the interior 14. The blade parts 24 are also pillow-like and planar, so that heat medium can be passed through them. The wall parts 24 and / or the blade parts 25 may also be perforated in a further embodiment for the introduction of tempered process gas.

In order to heat the inner wall 24 and the blading 25 of the heating module 20.1, a supply line 26 is circular encircling formed on a conduit 21 so that the walls 24 and the blades 25 are subjected to a heat medium via corresponding connections 28 to the supply line 26. In this case, for example, the introduced steam is supplied via connecting pieces 28 to an inner wall 24 and to a blading 25, respectively.

The inner walls 24 and the blade parts 25 are formed with a hollow chamber, so that the heat medium is passed through them. The walls 24 and the blade parts 25 are plate-shaped, wherein the walls 24 are arranged in the manner of a polygon. Characterized in that the walls 24 and the blading 25 are flat, results in a simplified, segmented structure of the drum dryer 10th

Steam is supplied to the supply pipe 21 via the inlet E1, the supply pipe 26 circulating in the circumferential direction being supplied with the heat medium from the pipe 21. From the supply line 26, the wall parts 24 and the blade parts 25 are supplied via corresponding connections with the heat medium. Via a second circulating line 27, the condensed heat medium (steam) is also derived from the wall parts 24 and the blade parts 25 via connecting pieces and the conduit 21 to the outlet A1.

Characterized in that the inner wall and the blades of a drum dryer into several wall segments (reference numeral 24) and a plurality of blade segments (reference numeral 25) are divided, it is possible to arrange corresponding heating modules along the conveying path of the tobacco from the entry to the discharge, so that the heating modules individually be provided with a predetermined temperature. For this purpose, further appropriate control devices or control devices are provided. For example, it is thereby possible that when heating the drum dryer, the heating modules are switched in time so that a corresponding temperature profile is formed along the conveying path of the tobacco, whereby a lesser approach shot is achieved.

LIST OF REFERENCE NUMBERS

10

drum dryer

11

role

12

frame

14

inner space

20.1, ..., 20.6

heating module

21

Pipeline

24

wall parts

25

blade part

26

supply line

27

management

28

joint

A1, A2, A3

output

E1, E2, E3

entrance

V

distribution unit

Z1, Z2, Z3

heat zone

Claims (16)

1. Method of drying tobacco material in an essentially horizontally oriented drying device (10) provided in the form of a drum dryer (10) for the tobacco processing industry, the drum dryer (10) being mounted in a rotating arrangement and displaced in rotation, and tobacco material is conveyed via an intake into an interior (14) of the drum dryer (10) and the dried tobacco material is conveyed out of the interior (14) via an outlet, characterised in that at least two zones (Z1, Z2, Z3) disposed one after the other in the tobacco flow are heated independently of one another by a heating medium, and the zones (Z1, Z2, Z3) of the drum dryer (10) have an annular heating module (20.1 to 20.6) with plate-shaped internal walls (24) disposed in the manner of a polygon, and the internal walls (24) are provided with a cavity and the heating modules (20.1 to 20.6) surround the interior (14) of the drum dryer (10).
2. Method as claimed in claim 1, characterised in that one zone (Z1, Z2, Z3) is cooled by a cooling medium.
3. Method as claimed in claim 1 or 2, characterised in that the heating medium and/or cooling medium is delivered to each zone (Z1, Z2, Z3) respectively via an intake line.
4. Method as claimed in one of claims 1 to 3, characterised in that the heating medium and/or cooling medium is fed away from each zone (Z1, Z2, Z3) respectively via a discharge line.
5. Method as claimed in one of claims 1 to 4, characterised in that a predefined zone temperature is set in each zone (Z1, Z2, Z3) at the internal walls (24) and/or the blades (25).
6. Drying device (10) for the tobacco processing industry for drying tobacco material, the drying device (10) being provided in the form of a drum dryer (10) with an intake through which tobacco material is conveyed into an interior (14) of the drum dryer (10) and with a discharge through which the dried tobacco material is conveyed out of the interior (14) of the drum dryer (10), and the drum dryer (10) is mounted in a rotating arrangement, characterised in that the drum dryer (10) has at last two zones (Z1, Z2, Z3) in the interior (14) disposed one after the other in the tobacco flow, which are or can be respectively heated independently of one another by means of a heating medium, and the zones (Z1, Z2, Z3) of the drum dryer (10) have an annular heating module (20.1 to 20.6) with plate-shaped internal walls (24), and the internal walls (24) are disposed in the manner of a polygon, and the internal walls (24) are provided with a cavity and the heating modules (20.1 to 20.6) surround the interior (14) of the drum dryer (10).
7. Drying device (10) as claimed in claim 6, characterised in that an intake line (21) for a heating medium and/or a discharge line (21) for a heating medium are provided for each zone (Z1, Z2, Z3).
8. Drying device (10) as claimed in claim 6 or 7, characterised in that the internal walls (24) and/or the blades (25) in each zone (Z1, Z2, Z3) are or can be heated by means of a heating medium.
9. Drying device (10) as claimed in one of claims 6 to 8, characterised in that the intake line (21) and/or the discharge line (21) are disposed essentially lengthways axially parallel with the axis of rotation of the drum dryer (10).
10. Drying device (10) as claimed in one of claims 6 to 9, characterised in that the intake line (21) and/or the discharge line (21) are disposed outside of the interior (14).
11. Drying device (10) as claimed in one of claims 6 to 10, characterised in that the walls (24) and/or the blades (25) are connected via supply lines (26, 27) to the intake line (21) and/or the discharge line (21).
12. Drying device (10) as claimed in claim 11, characterised in that the supply lines (26, 27) are disposed in the circumferential direction of the drum (10).
13. Drying device (10) as claimed in one of claims 6 to 12, characterised in that a heating circuit or cooling circuit is provided for each zone (Z1, Z2, Z3) of the drying device (10).
14. Drying device (10) as claimed in one of claims 6 to 13, characterised in that a control device is provided for at least one zone (Z1, Z2, Z3) for controlling the temperature of the zone (Z1, Z2, Z3) or a regulating device is provided for regulating the temperature of the zone (Z1, Z2, Z3).
15. Drying device (10) as claimed in one of claims 6 to 13, characterised in that a heat supply device (V) is provided respectively for at least one zone (Z1, Z2, Z3) of the drying device (10).
16. Plant in the tobacco processing industry with a drying device (10) as claimed in one of claims 6 to 15.

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