EP1033081B1 - Method and apparatus for puffing foodstuffs and stimulants - Google Patents

Abstract

The expansion method has the foodstuff or tobacco material fed through an expansion zone containing a Laval jet (4), using a carrier stream (13) containing between 10 and 100 % steam, with the sound velocity obtained in the narrowest cross-section of the expansion zone. The carrier stream may be preheated to a temperature of between 100 and 300 degrees C. An Independent claim for an expansion device for a foodstuff or tobacco material is also included.

Description

The invention relates to a method and a device for expansion of food or Consumable items. In particular, the inventive method and the invention Device for increasing the filling capacity of tobacco material or comminuted Smoking materials serve.

As regards the tobacco material, the term tobacco material or crushed Smoking materials entrippt tobacco leaf, tobacco rib, tobacco stem, each cut or shredded, recycled tobacco and tobacco by-products such as TV and ZHV winnowings be understood.

Freshly harvested green tobacco leaves contain relatively high levels of water, which means different Curingverfahren reduced to less than 10 mass% residual water content becomes. The water content is defined as the mass loss of the tobacco relative to the % Moisture content in% in a drying oven through a drying time of 3 Hours at 80 ° C (so-called Salvis moisture). This processed tobacco comes as a raw material, called raw tobacco, in the factories for the production of e.g. Cigarettes or others Beverages based on tobacco. The processing chain from the green leaf to the raw tobacco leads to a strong shrinkage. This reduction in volume adversely affects the so-called filling capacity.

The tobacco industry refers to filling as the property with as little mass use nevertheless produce physically stable, solid or hard end products (e.g., cigarettes) to be able to. (The filling capacity is also defined as the residual volume in relation to the weight in ml / g, which after compression with a 3kg weight in a cylindrical Setting vessel after a 30 second reaction time).

In the art, physical and chemical processing principles are known to the Undoing the shrinking process:

The physical processes (phase change to gaseous by heat) differ essentially by the impregnation / blowing medium and thus by the phase change. Examples are the impregnation with CO ₂ (phase change fixed to gaseous), the impregnation with fronen / liquefied gas (phase change liquid to gaseous) and the impregnation with highly stressed N ₂ (phase change dissolved according to gaseous)

Further worth mentioning are the proposed methods with organic solvents in liquid form and expelled as gas, with essentially all known low-boiling components have been described.

The variants of the chemical processes (generation of a gas by thermal decomposition or exothermic reaction) differ essentially by the type of gas generating reaction such as decomposition of additives by heat input in the dryer or by adding a further additive to initiate a reaction. Examples of this are the impregnation with NH ₃ / CO ₂ (thermal decomposition solid to gaseous), the impregnation with H ₂ O ₂ (thermal decomposition liquid to gaseous) and the impregnation with N ₂ H ₄ / H ₂ O ₂ (exothermic reaction liquid in gaseous form).

Only the physical processes have gained economic significance. Typical is the impregnation in the pressure range. The subsequent expulsion in the dryer takes place after the so-called fixation by depressurization / cooling to atmospheric pressure in Impregnator and thus brought about the formation of an equilibrium substance in the atmosphere becomes. The importance of these processes can be explained by the residue-free expulsion, inexpensive propellant and the volume increase in the order by a factor of 2.

A disadvantage of these methods is the introduction of additional additives and the Need for a pressurized process step in the tobacco treatment process. Of the Impregnation process is usually designed as a complex batch process.

The chemical processes are of no importance due to the residue problem obtained. In all known methods, the tobacco is either at atmospheric or overpressure impregnated with substances which in a second step, e.g. in a dryer, be transferred quickly from the solid or liquid state into a gaseous state. This Blähffekt leads to the increase in volume of tobacco structures. From DE 31 47 846 C2 a method for improving the filling known, the tobacco material of a carrier flow fed in a venturi and thereby expanded. The disadvantage here the need to optimize filling capacity increase.

As for the expansion of other expandable foods (e.g., cereals and legumes; "Puffing"), so in the prior art, several, mostly discontinuous Methods and devices described. To name here are the following fonts:

DE 195 21 243 describes a method and a device wherein in batch mode a closed container is pressurized and the material therein is heated. Of the Upper good-free area is briefly put under increased pressure. By sudden opening of the container, the material is ejected into an expansion chamber at atmospheric pressure. The increased pressure acts as a propellant. The water in the estate evaporates and the estate is expanding.

DE 195 21168 describes apparatus and method analogous to DE 195 21 243, however the inner container has no holes in the upper good-free area.

DE 195 21167 describes a device analogous to DE 195 21243 and DE 195 21 168 wherein the expansion chamber is rotatable and the expanded material by rotation of the drum is discharged in the longitudinal direction.

DE 198 06 951 describes an apparatus and a method for puffing granular Good, especially a preheating chamber for the good to be expanded. The used Heating device comprises a fluidized bed chamber in which the material is heated batchwise becomes. With the help of a branch circuit, the material is transferred to the puffing reactor.

In DE 198 06 950 an expansion chamber is described which is designed in two parts is. The first part starts directly at the outlet of the expansion chamber and has a long, slender and conical shape. He is calculated to have a laminar flow formed. It ends in the second part, in which no later than normal pressure is reached. There the flow becomes turbulent.

Even after this state of the art can not be optimally expanded, and in the Batch operation discontinuous systems are complex and not very effective.

From DE 33 15 274 A1 discloses a method and apparatus for increasing the volume known by tobacco. Here, a pipe section is used, which is called "Laval nozzle" is referred to, but only has a comically narrowing tube. At a Such flow guidance can be an optimal expansion due to the occurring Pressure ratios can not be achieved.

This invention has set itself the task of the above-mentioned disadvantages of the prior art overcome the technique. In particular, optimal expansion should be effectively possible and with regard to the tobacco material, the mentioned reduction in filling capacity / shrinkage as far as possible undone.

This object is achieved by the subject matters of the independent claims solved. The subclaims describe preferred embodiments of the invention.

The invention allows in the tobacco area advantageously not reached Füllfähigkeitssteigerungen with filling capabilities after expansion, which can be up to about ten percent above the values for usual, so far generally regarded as optimized expansion methods lie. The positive effects on the efficiency of smoking article production are enormous in the quantities of tobacco used in industry. In the field of others expandable food and beverages are corresponding benefits.

In the method according to the invention, the material continuously passes through an area higher Pressure, subsequently an area of reduced pressure and finally an area atmospheric pressure.

The core principle of the process utilizes the property of gases and vapors of pressure energy to convert completely into kinetic energy by means of a nozzle (extreme case: Pressure reduction up to 0 bar). This extreme pressure reduction succeeds only if at the narrowest point the nozzle reaches the speed of sound or, equivalently, the critical pressure ratio becomes. Under these conditions, a further pressure reduction and thus speed increase in the extended section of the nozzle.

The classically operated nozzle results in the extended part under the same conditions Pressure increase and thus speed reduction. These relationships are in the enclosed Fig. 4, which in the upper illustration a principal nozzle structure and below which shows the speed and pressure curves in different operating modes. The course denoted by a circled 1 applies here to a nozzle in the subcritical Operation, while the courses, which are marked with the circled 2, for a Laval nozzle in critical operation apply (at supersonic speed), as in the present Invention is used.

If you load now a carrier flow (example saturated steam) before nozzle inlet, for. with tobacco material, so the particles are depending on the input conditions on the temperature and the Pressure of the vapor equilibrated (example 4 bar, 143 ° C). After the entry of the two-phase mixture The wet particle gets into the negative pressure part of the Laval nozzle (example 0.2 bar) at high temperature to imbalance (boiling point of water at 0.2 bar: 60 ° C) and to Cooling is vaporized tobacco moisture. This forced evaporation will be out of the inner Energy of the particle fed. Heat transfer from the environment is due to the temperature conditions (Steam colder than particles) in the vacuum area not possible. Heat transport processes take place by heat conduction from inside to outside in the particle. in principle is this type of dehumidification / drying different from the so-called convection airflow dryers, in which the energy needed to evaporate from the gas to the particle is transmitted.

Due to the very low pressure at the nozzle outlet of the Laval nozzle can so advantageously the high Füllfähigkeitssteigerungen be achieved. Furthermore, the invention allows a continuous process, integrable in e.g. a tobacco preparation process without special steps (In particular, integration without previous tobacco discharge is in one Air flow dryer possible). This results in only a small additional expenditure on equipment and additional tobacco preparation process steps such as casing / flavoring are without further integrable.

The carrier flow may have a steam content of 10 to 100% saturated steam and in particular have superheated steam.

In one embodiment of the invention, the pressure of the carrier flow is in front of the Laval nozzle in one area to 10 bar, and the temperature of the carrier flow in front of the Laval nozzle is in a range of 50 ° C to 450 ° C, preferably in a range of 100 ° C to 300 ° C.

The pressure at the outlet of the Laval nozzle can at 0 bar to 2 bar, preferably at 0.2 bar to 1 lie bar.

In particular, embodiments for the expansion of tobacco material will be described below described. However, these embodiments are basically based on the expansion of others Food or beverage applicable. This includes the processing of solid, fibrous, grain-shaped or leaf-shaped food, e.g. Grain and legumes, cereals, barley, maize, beans, wheat, rice or peas. Device components, such as separators are then the respective processed Material adapted.

Preferably, the carrier flow is overheated prior to introduction of the material / tobacco material.

In a preferred embodiment of the method according to the invention passes through the Trägerströmung an inlet section, a nozzle pre-chamber, the Laval nozzle, an inlet diffuser and an outlet diffuser.

The tobacco material can be the carrier flow on the one hand in the inlet section before the Laval nozzle, preferably via a rotary valve with an attaching to the inlet line Headpiece to be supplied.

As regards the further processing of the tobacco material, it is possible according to the invention Tobacco material after passing through the outlet diffuser a tobacco separator, in particular to supply a centrifugal separator, the negative pressure preferably by means of a vacuum compressor is maintained. The tobacco material can also after the passage through the outlet diffuser first an air dryer and then a tobacco separator, in particular a centrifugal separator are supplied.

In an advantageous embodiment of the method according to the invention, the gas flow, which passes the adjoining the outlet diffuser components by means of a Recirculation system collected, compressed and used again as a carrier flow component.

The device according to the invention is preferably characterized in that it comprises a device in particular, has a heat exchanger, which the carrier flow before introduction of the tobacco material overheats.

The flow guidance devices comprise in one embodiment of the device Inlet section, a nozzle pre-chamber, the Laval nozzle, an inlet diffuser and an outlet diffuser.

A rotary valve with a head attached to the inlet section can be provided be, by means of the tobacco material of the carrier flow in the inlet section in front of the Laval nozzle is supplied.

The device preferably has a tobacco separator, in particular a centrifugal separator, on which the tobacco material is supplied after passing through the outlet diffuser is, and its negative pressure is preferably maintained by means of a vacuum compressor becomes.

In another embodiment, the device has an air flow dryer and to these then a tobacco separator, in particular a centrifugal separator, on which the Tobacco material is supplied after passage through the outlet diffuser.

It is of particular advantage to provide a recirculation system by means of which the gas flow, which passes the components adjoining the outlet diffuser, collected, compressed and again the carrier flow is supplied.

Fig. 1

eine Schemadarstellung einer Expansionsvorrichtung für Tabakmaterial mit einem anschließenden Zyklonabscheider gemäß einer ersten Ausführungsform der Erfindung;

Fig. 2

eine Schemadarstellung einer Expansionsvorrichtung für Tabakmaterial mit einem anschließenden Trockenturm gemäß einer zweiten Ausführungsform der Erfindung;

Fig. 3

ein Balkendiagramm, das die Füllfähigkeitssteigerung bei erfindungsgemäßen Verfahren und bei Vergleichsverfahren nach dem Stand der Technik gegenüberstellt; und

Fig. 4

eine schematische Darstellung eines Düsenquerschnittes mit Druck- und Geschwindigkeitsverläufen für den kritischen und nicht kritischen Betrieb.

The invention will be explained in more detail below with reference to the accompanying drawings by means of the description of exemplary embodiments. Show it:

Fig. 1

a schematic representation of a tobacco material expansion device with a subsequent cyclone separator according to a first embodiment of the invention;

Fig. 2

a schematic representation of a tobacco material expansion device with a subsequent drying tower according to a second embodiment of the invention;

Fig. 3

a bar graph comparing the Füllfähigkeitssteigerung the inventive method and prior art comparison methods; and

Fig. 4

a schematic representation of a nozzle cross-section with pressure and speed curves for critical and non-critical operation.

In FIGS. 1 and 2, the reference numerals 1 designate an inlet section, 2 a rotary valve, 3 a nozzle prechamber, 4 a Laval nozzle (also referred to as a propulsion nozzle), 5 Head on the Laval nozzle, 6 an inlet diffuser, 7 an outlet diffuser, 8 a discharge lock, 9 a cyclone separator, 10 a compressor, 11 a recirculation system, 12 a Exhaust air system, 13 a carrier flow, 14 a tobacco discharge from the cyclone separator, 15 a drying tower, 16 an optional casing / flavor feed, 17 a carrying air feed to the drying tower and 18 the discharge from the drying tower. T indicates tobacco material. Like reference numerals indicate like components.

Figures 1 and 2 show those embodiments of the invention in which the tobacco material in the inlet section, ie on the pressure side of the Laval nozzle in the carrier flow 13 is fed.

FIG. 1 illustrates an embodiment with a direct separation in the tobacco separator 9 after the nozzle 4. The tobacco is through a lock, preferably through a Rotary valve 2, which is suitable for larger differential and absolute pressures, into the inlet section 1 promoted. There, the tobacco is mixed with the carrier flow 13, preheated and moistened when using steam. The mass flow ratio of carrier flow Tobacco material can be easily selected by choosing the narrowest cross section in the Laval nozzle 4 (motive nozzle) can be set at a given mass flow of the tobacco material. For example, at 2 bar saturated steam inlet pressure (about 120 ° C), a maximum mass flow of 400 kg / h with nozzle diameter 21.8 mm; however, at 15.4 mm nozzle diameter a maximum throughput of 200 kg / h achieved. The useful ratio is in the range 0.1-10 kg carrier flow per kg of tobacco material. After passing the Nozzle prechamber 3 and nozzle 4 adjusts depending on the adiabatic expansion Type of carrier flow, after construction of the apparatus and after the procedure low pressure and thus a corresponding low temperature of the carrier flow one. The tobacco material tries the temperature imbalance by evaporation and Removal of internal energy, by charging in the entrance area the tobacco material was imposed to counteract. Preferably, at the outlet of the Laval nozzle 4th Pressures of less than 1 bar. Depending on the desired process pressure in the tobacco separator 9, the steam must be compressed using the inlet / outlet diffuser 6/7 become.

This process variant according to FIG. 1 is preferably at those subsequent to the expansion Tabaktrocknungsverfahren displayed which the carrier flow 13 not as drying or transport medium. These are z. B. the drum, vibro / fluidized bed or Belt drying. These drying methods require the prior separation of tobacco material and carrier flow by means of a tobacco separator, preferably a Centrifugal separator 9, such. B. cyclone or Tangentialseparator occurs. Should the benefits used the vacuum expansion without subsequent compression to atmospheric pressure must, in the sense of drum or Vibro- / fluidized bed or belt drying the tobacco material are also separated from the carrier flow, the tobacco discharge 14 from the vacuum to the atmospheric pressure area. The negative pressure in the tobacco separator 9 can be maintained, for example, by a vacuum pump, not shown become.

In the embodiment shown in Fig. 2, the tobacco material deposition takes place after a passage of a Luftstromtrockners, here a drying tower 15th

The tobacco is directly without separation of the carrier flow 13 after passage of the diffuser 6/7 passed into the drying tower 15 and after moistening on the tobacco separator 9, preferably a centrifugal separator, such as. B. cyclone or tangential separator, by means a discharge lock 8 discharged (arrow 14). For this it is necessary, the carrier flow 13 with respect to speeds and pressure to adapt to the conditions in the drying tower 15. In this case, an operation of the expansion is preferred in which in the outlet diffuser 7 pressures are present, which are between 0.9-1.1 bar.

The two variants according to FIGS. 1 and 2 together have the option of circulating air / partial recirculation mode of operation by means of recirculation system 11 for reuse of the carrier flow 13, preferably in air as a carrier flow 13, the consideration of the economy as particularly cost-effective solution can be used.

Furthermore, both variants optionally allow the introduction of liquid / solid additives (casing, Flavor) in the head region 5 at the Laval nozzle 4, as in Fig.2 with the reference numeral 16 is indicated.

FIG. 3 shows a bar chart showing the increase in filling capacity in accordance with the invention Compared to the prior art method and comparison method. The Experimental parameters are shown below:

Experiment 1 (Laval nozzle):

Tobacco Material:

Standard ribs mixture

System design:

see Fig. 1 (without compressor 10, without circulating air, without optional casing, flavor)
Nozzle diameter: 15 mm

Carrier flow:

saturated steam

Parameter:

2.2 bar pre-pressure (Pos. 3), pressure in nozzle 0.6 bar (Pos. 6), steam temperature approx. 123 ° C in pos. 3, steam temperature in cyclone (Pos. 9) approx. 100 ° C,
Steam pressure in cyclone (item 9) approx. 1 bar
Carrier mass flow / tobacco mass flow ratio 0.67,
Tobacco moisture in front of expansion device (in front of lock pos. 2) approx. 40% (wet basis),
Tobacco moisture after expansion device (after cyclone pos. 9) approx. 43.5% (wet basis)

Experiment 2 (Laval nozzle):

Tobacco Material:

Standard ribs mixture

System design:

see Fig. 1 (without compressor 10, without circulating air, without optional casing, flavor)
Nozzle diameter: 15 mm

Carrier flow:

saturated steam

Parameter:

2.2 bar pre-pressure (pos. 3), pressure in nozzle 0.65 bar (pos. 6), vapor temperature approx. 123 ° C in pos. 3, vapor temperature in cyclone (pos. 9) approx. 100 ° C, vapor pressure in cyclone (item 9) approx. 1 bar
Carrier flow mass flow / tobacco mass flow ratio 0.43, tobacco moisture before expansion device (in front of lock pos. 2) approx. 40% (wet basis),
Tobacco moisture after expansion device (after cyclone pos. 9) approx. 43% (wet basis)

Trial 3 (STS nozzle):

Tobacco Material:

Standard ribs mixture

System design:

Commercially available STS device

Carrier flow:

saturated steam

Parameter:

Carrier mass flow / tobacco mass flow ratio 0.67, Tobacco moisture before expansion device approx. 40% (wet basis), Tobacco moisture after expansion device approx. 44% (wet basis)

Trial 4 (STS nozzle):

Tobacco Material:

Standard ribs mixture

System design:

Commercially available STS device

Carrier flow:

saturated steam

Parameter:

Carrier mass flow / tobacco mass flow ratio 0.47, Tobacco moisture before expansion device approx. 40.7% (wet basis), Tobacco moisture after expansion device approx. 44.3% (wet basis)

Trial 5 (Laval nozzle):

Tobacco Material:

Standard ribs mixture

System design:

see Fig. 1 (without compressor 10, without circulating air, with casing in suction nozzle (Pos. 5), Nozzle diameter: 15 mm

Carrier flow:

saturated steam

Parameter:

2.2 bar pre-pressure (Pos. 3), pressure in nozzle 0.6 bar (Pos. 6), steam temperature approx. 123 ° C in pos. 3, steam temperature in cyclone (Pos. 9) approx. 100 ° C, vapor pressure in cyclone (item 9) approx. 1 bar
Carrier flow mass flow / tobacco mass flow ratio 0.67, tobacco moisture before expansion device (in front of lock pos. 2) approx. 40% (wet basis),
Tobacco moisture after expansion device (after cyclone pos. 9) approx. 46% (wet basis)

It can easily be seen that the increase in filling capacity and the achieved absolute values in experiments 1, 2 and 5, which used a method according to the invention, are significantly larger than in the previously regarded as optimized STS process whose Results by the bar for experiments 3 and 4 are shown. It is according to the invention about 10% higher filling capabilities. The positive effects on the Efficiency of smoking article manufacture are among those used in the industry Tobacco material amounts enormously.

In the table which is still exhaustive, suitable and preferred parameter values for carrying out the process according to the invention are summarized again. parameter total area Preferred area Carrier flow pressure in front of nozzle 1-30 bar 1-10 bar Carrier flow temperature before nozzle 50-450 ° C 100-250 ° C Carrier flow pressure in nozzle > 0-2 bar 0.2-1.0 bar Carrier flow pressure in outlet diffuser (item 7) > 0-2 bar 0.2-1.1 bar Tobacco moisture in front of the inlet rotary valve 10-60% (wet basis) 17-45% (wet basis) Tabaktemperatur before inlet rotary valve 10-100 ° C 20-95 ° C Ratio of carrier mass flow / tobacco mass flow 0.1-10 (kg / h) / (kg / h) 0.2-1 (kg / h) / (kg / h) Vapor content carrier flow 10-100% (mass percent wet basis) 50-100% (mass percent wet basis)

All pressure data used are absolute values.

There have also been attempts to expand other food and beverages and with good expansion results. In particular, barley and corn were suitable for the inventive expansion to produce puffed shapes. The experimental setup in this case basically corresponded to that after the experiment 1 described above, which Plant construction and carrier flow concerns.

Claims (22)

1. A method for expanding expandable foodstuffs and/or luxury foodstuffs, wherein the foodstuffs and/or luxury foodstuffs in a carrier flow (13) containing steam pass through an expansion zone comprising a Laval nozzle (4), characterised in that the foodstuffs and/or luxury foodstuffs are introduced into a nozzle antechamber (3) in which an absolute pressure of more than 1 to 30 bars prevails, and in that the speed of sound is reached in the narrowest cross-section of the Laval nozzle (4).
2. The method as set forth in claim 1, characterised in that tobacco material, in particular moist tobacco material (T), is expanded.
3. The method as set forth in claim 1, characterised in that solid, fibrous, grainy, bean or leafy foodstuffs and/or luxury foodstuffs are expanded.
4. The method as set forth in claim 3, characterised in that one or more of the following foodstuffs and/or luxury foodstuffs are expanded: grains and legumes, cereals, barley, maize, beans, wheat, rice, peas.
5. The method as set forth in any one of claims 1 to 4, characterised in that the carrier flow (13) comprises a steam content of 10 to 100% and/or the tobacco input moisture content is 10 to 60 % (moisture basis), preferably 17 to 45 % (moisture basis).
6. The method as set forth in any one of claims 1 to 5, characterised in that the carrier flow (13) comprises saturated steam.
7. The method as set forth in any one of claims 1 to 6, characterised in that the carrier flow (13) comprises superheated steam.
8. The method as set forth in any one of claims 1 to 7, characterised in that the pressure of the carrier flow (13) upstream of the Laval nozzle is in a range of up to 10 bars, and in that the temperature of the carrier flow (13) upstream of the Laval nozzle (4) is in a range of 50°C to 450°C, preferably in a range of 100° to 300°C.
9. The method as set forth in any one of claims 1 to 8, characterised in that the pressure at the output of the Laval nozzle (4) is 0 to 2 bars, preferably 0.2 to 1 bar.
10. The method as set forth in any one of claims 1 to 9, characterised in that the carrier flow (13) is superheated prior to introducing the foodstuffs and/or luxury foodstuffs, in particular the tobacco material.
11. The method as set forth in any one of claims 1 to 10, characterised in that the carrier flow passes through an infeed zone (1), a nozzle antechamber (3), the Laval nozzle (4), an infeed diffusor (6) and an outfeed diffusor (7).
12. The method as set forth in claim 11, characterised in that the foodstuffs and/or luxury foodstuffs, in particular the tobacco material, are supplied to the carrier flow (13) in the infeed zone (1) upstream of the Laval nozzle (4), preferably via a cellular wheel sluice (2) comprising a header (5) placed onto the infeed zone (1).
13. The method as set forth in any one of claims 11 or 12, characterised in that the foodstuffs and/or luxury foodstuffs, in particular the tobacco material, once they have passed through the outfeed diffusor (7), are supplied to a separator, in particular a tobacco separator (9), specifically a centrifugal separator, in which a vacuum is preferably maintained by means of a vacuum pump.
14. The method as set forth in any one of claims 11 or 12, characterised in that the foodstuffs and/or luxury foodstuffs, in particular the tobacco material, once it has passed through the outfeed diffusor (7), is supplied first to an air-flow dryer (15) and then to a separator, in particular a tobacco separator (9), specifically a centrifugal separator.
15. The method as set forth in any one of claims 13 or 14, characterised in that the gas flow passing the components adjoining the outfeed diffusor (7) is collected, compressed and recycled as part of the carrier flow by means of an air recycling system (11).
16. An apparatus for expanding foodstuffs and/or luxury foodstuffs, in particular moist tobacco material (T), comprising flow guidance means (1, 3, 4, 6, 7) in which the foodstuffs and/or luxury foodstuffs, in particular the tobacco material (T), in a carrier flow (13) containing steam pass through an expansion zone, wherein the flow guidance means comprise a Laval nozzle (4), characterised in that the Laval nozzle (4) is operated such that the speed of sound is reached in its narrowest cross-section and in that a nozzle antechamber (3) is provided, into which the foodstuffs and/or luxury foodstuffs are introduced and in which an absolute pressure of more than 1 to 30 bars prevails.
17. The apparatus as set forth in claim 16, characterised in that it comprises a means, in particular a heat exchanger, which superheats the carrier flow (13) prior to introducing the tobacco material.
18. The apparatus as set forth in claim 16 or 17, characterised in that the flow guidance means comprise an infeed zone (1), a nozzle antechamber (3), the Laval nozzle (4), an infeed diffusor (6) and an outfeed diffusor (7).
19. The apparatus as set forth in claim 18, characterised in that it comprises a cellular wheel sluice (2) comprising a header (5) placed onto the infeed zone (1), by means of which the foodstuffs and/or luxury foodstuffs, in particular the tobacco material, are supplied to the carrier flow (13) in the infeed zone (1) upstream of the Laval nozzle (4).
20. The apparatus as set forth in any one of claims 18 or 19, characterised in that it comprises a separator, in particular a tobacco separator (9), specifically a centrifugal separator, to which the foodstuffs and/or luxury foodstuffs, in particular the tobacco material, are supplied once they have passed through the outfeed diffusor (7), and in which a vacuum is preferably maintained by means of a vacuum pump.
21. The apparatus as set forth in any one of claims 18 or 19, characterised in that it comprises an air-flow dryer (15) and a separator adjoining it, in particular a tobacco separator (9), specifically a centrifugal separator, to which the foodstuffs and/or luxury foodstuffs, in particular the tobacco material, are supplied once they have passed through the outfeed diffusor (7).
22. The apparatus as set forth in any one of claims 20 or 21, characterised in that it comprises an air recycling system (11), by means of which the gas flow passing the components adjoining the outfeed diffusor (7) is collected, compressed and re-supplied to the carrier flow.

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