CN1400873A - Method for improving the filling ability of tobacco - Google Patents

Abstract

The present invention relates to a method for improving the fillability of tobacco, as cut tobacco leaves or ribs and/or plant-based tobacco additives with cellular structure, by treating the tobacco material which has 8 to 16 wt. % initial moisture with a treatment gas consisting of nitrogen and/or argon at pressures of 50 to 1,000 bar in either one autoclave or with cascade-type switching in several autoclaves, followed by thermal after-treatment of the tobacco material discharged after decompression has occurred, which is characterised in that the decompression is carried out with at least one holding stage whose pressure corresponds to 3 to 60%, preferably 3 to 30% of the original maximum pressure and that the heating of the system whilst it is under residual pressure is carried out in such a way that the tobacco discharge temperature after pressure reduction is completed lies within the range 10 to 80 DEG C. The temperature increase of the system whilst it is under residual pressure is effected by a holding time, circulation via a heat exchanger and/or by transfer of heated gas, with the reduction in pressure being carried out from the maximum pressure in each case to the pressure of the holding stage within an interval of 20 seconds to 5 minutes and the reduction of the residual pressure being carried out within an interval of 3 seconds to 3 minutes.

Description

Method for Improving Filling Capacity of Tobacco

The invention relates to a method for increasing the filling capacity of tobacco materials, such as shredded tobacco, tobacco stems or plant tobacco additives with a porous structure, the method is an autoclave at a pressure of 50-1000 bar or a plurality of In an autoclave, tobacco material having an initial moisture content of 8 to 16 wt.% is treated with a treatment gas consisting of nitrogen and/or argon, and then, after pressure relief, the discharged tobacco material is subjected to a secondary heat treatment .

The method of expanding tobacco with an inert gas at high pressure, as known by the INCOM expansion process, has many advantages over the treatment of tobacco under pressure with carbon dioxide, ammonia or volatile organic gases, as disclosed in US 4 289 148 A method of treating tobacco material with a moisture content greater than 20% by weight in an autoclave operating at a temperature between 0°C and 50°C. The depressurization is carried out within 0.5 to 10 minutes, and in the embodiment, the depressurization is carried out within 1.3 minutes, and then the discharged tobacco is subjected to a secondary heat treatment such as with saturated steam to expand it.

DE 31 19 330 A1 discloses that tobacco material with a low moisture content of 10 to 15 wt.% is operated at temperatures below 50°C in order to allow rapid cooling of the tobacco material to be expelled when the expansive force is released. The depressurization time in this case was 1.3 to 2 minutes.

DE 34 14 625 C2 discloses a tandem process according to which low impregnation temperature tobacco is obtained by cooling the process gas before feeding into the reactor, by cooling the autoclave or by using subcooled and liquefied process gas . The pressure release time is 0.5 to 10 minutes, preferably 1 to 2 minutes. The minimum temperature of the discharged tobacco should be below 0°C.

Similarly, DE 39 35 774 C2 also discloses a cascade expansion process by circulating the process gas with a condenser to obtain the required low impregnation temperatures of 25°C and 45°C.

Although good results are obtained with this known expansion method in terms of increasing tobacco filling capacity and/or expansion, due to the cooling required for an autoclave or several autoclaves and due to the additional cooling required for the process gases, So the cost is relatively expensive.

The object of the present invention is to improve the existing INCOM process and obtain equally good or better expansion without expensive cooling measures.

Therefore, the method of the present invention is the type mentioned at the beginning of the preamble of the claims of the present invention, is characterized in that: carry out depressurization treatment in at least one holding stage, the pressure that bleeds off is equivalent to the original maximum pressure 3 to 60%, preferably 3 to 30%, and it is also characterized in that: under the residual pressure, the system is heated so that after the pressure is completely released, the discharge temperature of the tobacco is in the range of 10°C to 80°C.

It has surprisingly been found that low temperature treatment and/or low temperature discharge of tobacco with a low moisture content in the range of 8 to 16 wt.% does not result in optimum expansion using existing principles. On the contrary, surprisingly good results can be obtained in terms of expansion effect and/or filling capacity under residual pressure only by heating the system, wherein, according to the method, the heat of compression is advantageously used and does not have to be induced. away, and without additional cooling of an autoclave or autoclaves.

The pressure relief from the respective maximum pressure drop to the holding stage pressure is preferably carried out within a time interval of 20 seconds to 5 minutes, and the pressure relief of the residual pressure is carried out within a time interval of 3 seconds to 3 minutes.

In addition, in order to reach the tobacco discharge temperature according to the invention, it is suitable to increase the temperature by holding time, by circulating the gas under residual pressure by means of a heat exchanger and/or by sending heated gas from other autoclaves.

In other preferred variants of the method, the same tobacco material is autoclaved several times or successively autoclaved and heat treated.

Particularly good results are obtained if the tobacco material has an initial moisture content in the range of 10 to 14 wt. % and if the tobacco material is further subjected to a secondary heat treatment with saturated steam.

This method of the present invention is explained below with reference to examples.

Example 1

In order to carry out the method of the present invention, but also in order to carry out comparative tests, in a laboratory autoclave with a volume of 2 liters, a process gas consisting of nitrogen is used to carry out high-pressure treatment, wherein, in order to adjust to the required operating temperature, use jacket to circulate the liquid medium. Pressure supply/gas supply is performed on the lower side of the autoclave, and pressure release/gas discharge is performed on the upper side of the autoclave. To adjust the final pressure, a compressor is used, while the temperature of the tobacco is measured in the upper and upper half of the tobacco filler with a thermocouple element.

The test rig for secondary heat treatment of tobacco consisted of a permeable conveyor belt/wire mesh operating at a speed of approximately 5 cm/s. The tobacco nets (Tabakvlies) between the guide plates are subjected to secondary treatment under about 10 kg/h of saturated steam, about 8 mm long and narrow outlets, and about 160 mm wide steam nozzles. The extraction device for steam is located under the conveyor belt opposite to the steam nozzle.

Tobacco samples treated in this way were spread on flat plates and the temperature and relative humidity were adjusted to 21°C and 60%, respectively.

The filling capacity is determined with a Borgwaldt density measuring instrument and the specific volume is converted into ml/g at a standard humidity (Sollfeuchte) of 12% by weight and a standard temperature (Solltemperatur) of 22°C. From the data from the untreated control and swelled samples, the following relative increase in fill capacity and/or swell was calculated:

Δ%=(F _E -F _B )*100%/F _B

(F _B is the untreated filling capacity, F _E is the expanded filling capacity)

Tobacco was extracted with a PVC pipe with a perforated bottom inserted into the autoclave. During pressurization, gas was supplied to achieve a final pressure of 700 bar. As tobacco, 300 g of flue-cured tobacco (Virginia-Blend) with a moisture content of 12% was used. The test results are shown in the table below, where T _A represents the exit temperature of the autoclaved tobacco. During the depressurization of test 1, two holding phases were maintained at 400 bar and 100 bar for 2 minutes, and in tests 2 and 3, only one holding phase was maintained at 50 bar for 2 min/4 min . In comparative test 4, the pressure release is performed directly, if the pressure release time is less than 1 minute, there is no holding stage.

Table 1: Test results Operating temperature °C 60 80 serial number Pressure relief operation T _A ℃ Δ% T _A ℃ Δ% 1 2 minutes for each holding phase at pressures of 400 bar and 100 bar 16 83 - - 2 Hold phase at 50 bar for 2 minutes 15 93 20 90 3 Hold phase at 50 bar for 4 minutes 33 93 41 90 4 no (comparison) -25 80 -3 81

The above-mentioned tests No. 1 to No. 3 were carried out at different pressures and different times and at the operating temperature of two autoclaves during the holding stage. Compared with the test 4 of direct pressure relief, the above-mentioned tests showed that: in the predetermined holding stage ( The holding time in the pressure) makes the discharge temperature significantly increase from -25°C or -3°C to +33°C or +41°C, and contrary to the existing process principle, the present invention still improves the filling capacity despite the high discharge temperature.

Example 2

Similar to Example 1, 150 g of tobacco was autoclaved at the operating temperature of the autoclave at 40°C. During the depressurization of test 5, the holding phase was maintained at a pressure of 50 bar for 2 minutes, and during the holding time the gas was circulated by means of a circulation pump through a heat exchanger at a temperature of 80°C. This time, the gas supply during the depressurization and circulation process is performed from the upper side of the autoclave, and the discharge and depressurization of the holding stage gas are performed from the lower side of the autoclave. A sealing ring between the upper end of the tobacco insertion container and the autoclave lid ensures direct gas access into the tobacco insertion container.

Table 2: Test results Operating temperature 40°C serial number Operation during depressurization T _A ℃ Δ% 5 Hold phase at 50 bar for 2 minutes, cycle through heat exchanger (80°C) 10 79 6 no (comparison) -105 69

Example 3

The following procedure is similar to that of Example 2, wherein, during the depressurization, the pressure of the holding phase is kept constant at 50 bar for 1 minute, and the pressure from the second autoclave (referred to as "Donator") is Heated gas is introduced into the processing vessel. Before this transfer, the pressure of the donor was 100 bar, the operating temperature was 80° C., and the volume was 4 L. During depressurization and transfer, the gas supply is carried out from the bottom of the autoclave, and the gas outlet for the holding stage and depressurization is above the autoclave.

Table 3: Test results Operating temperature 40°C serial number Operation during depressurization T _A ℃ Δ% 7 The hold phase is maintained for 1 min at a pressure of 50 bar, delivering gas from a supply at a pressure of 100 bar and an operating temperature of 60 °C 16 89

In Example 1, heating during a holding time with a predetermined holding stage/predetermined pressure necessitates an increase in the operating temperature. In contrast to Example 1, the above-mentioned Examples 2 and 3 show that: when the process vessel containing the gas (referred to as "Acceptor (Akzeptor)") at an operating temperature of 40°C, both the gas circulation through the heat exchanger of Example 2 and the transfer of gas from the donor in Example 3 are in a constant holding phase/constant Under pressure also increases the operating temperature. The variant method of delivering gas from the supply container of Example 3, in particular, results in a significantly higher filling capacity than Control 6 of Example 2.

To account for these unexpected results, it may be hypothesized that heat treatment of autoclaved tobacco at residual pressure results in a pre-expansion of the tobacco in the autoclave, yielding an additional improvement in filling capacity not obtainable by known methods. To confirm this hypothesis in Example 4 below, tobacco was pressure-treated without secondary heat treatment with saturated steam, and the treated samples were directly conditioned for a possible effect of pre-expansion. It has been confirmed that the improvement of the filling ability without the secondary heat treatment is small, but in Example 4 below, during the heating with the residual pressure, an additional effect occurs.

Example 4

150 g of tobacco was autoclaved at the operating temperature of the autoclave at 60° C., and after the pressure was completely released, the tobacco was not subjected to secondary heat treatment. During the depressurization, the holding phase was maintained for 1 minute at a pressure of 50 bar, similarly to Example 3, by transferring heated gas from the second autoclave, before transferring the gas, the pressure of the supply body was 200 bar, and the operating temperature was 80 ℃. In Control Test 9, there was no holding phase, and the depressurization was performed directly.

Table 4: Test Results Operating temperature 60°C serial number Operation during depressurization T _A ℃ Δ% 8 Hold phase at 50 bar for 1 min, delivering gas from a supply at 200 bar and operating at 80 °C 19 twenty one 9 no (comparison) -69 8

The above results confirm the hypothesis that under the pressure of the tobacco residue there is a slight pre-expansion during the heating of the autoclaved tobacco prior to the secondary heat treatment with saturated steam.

Examples 5 and 6 below illustrate another embodiment of the method of the present invention in which multiple autoclave/autoclave and secondary heat treatments are performed on the same tobacco material.

Example 5

In the first stage, 150 g of tobacco were autoclaved at an operating temperature of the autoclave at 60°C. Similar to Example 3, the heated process gas is delivered from the supply so that the holding stage has a constant pressure. The pressure of the supply was 300 bar, the operating temperature was 80° C., and the holding phase was regulated for 1 minute at a pressure of 200 bar before delivery of the gas.

Tobacco material from the first stage, expanded and conditioned according to Test 10, was used as primer for an additional treatment cycle consisting of autoclaving and secondary heat treatment. 100 g of tobacco were autoclaved at an operating temperature of the autoclave of 60°C. And during the depressurization, the holding phase is maintained at a pressure of 100 bar for 1 minute. The pressure of the donor vessel was 200 bar and the operating temperature was 80° C. before delivery of gas. Table 5 shows the results of this test and test 10.

Table 5: Test Results Operating temperature 60°C serial number Operation during depressurization T _A ℃ Δ% 10 Hold phase at 200 bar for 1 min, delivering gas from a supply at 300 bar and operating at 80 °C 26 86 11 Hold phase at 100 bar for 1 min, delivering gas from a supply at 200 bar and operating at 80 °C twenty four 116 (expanded tobacco treatment to test 10)

Example 6

The following steps are similar to those of Example 5, except that in this example, two identical pressure treatment cycles were performed one after the other, followed by secondary heat treatment. The result is as follows: Operating temperature 60°C serial number Operation during depressurization T _A ℃ Δ% 12 The hold phase is maintained for 1 min at a pressure of 100 bar, delivering gas from a supply at a pressure of 200 bar and an operating temperature of 80 °C 30 103 (after two pressure treatments followed by a second heat treatment)

Whereas the expanded tobacco material from Stage 1 of Example 5 was reprocessed in Stage 2, in this Example 6 two cycles of pressure treatment were performed consecutively followed by a second cycle of pressure treated tobacco material. heat treatment. These two methods are based on the principle of multiple expansion, that is: repeated continuous high pressure treatment and secondary heat treatment or repeated one high pressure treatment followed by secondary heat treatment.

Example 5 shows that the effect of the first expansion stage can be further enhanced by retreatment of stage 2 and results in a tobacco material with very high filling capacity. Example 6 is simpler due to the elimination of the secondary processing stage, but it does not reach the maximum value of Example 5.

Claims (9)

1. improve the method for tobacco-containing material filling capacity; as improve pipe tobacco; offal or have the method for the plant tobacco additive filling capacity of cellular structure; this method is under the pressure of 50-1000 crust; in an autoclave or a plurality of autoclaves of being connected in series; using the processing gas be made up of nitrogen and/or argon gas is that 8 to 16wt% tobacco-containing material is handled to original water content; subsequently; after pressure release; the tobacco-containing material that is discharged from is carried out post bake to be handled; it is characterized in that: carry out pressure release at least one maintenance stage and handle; the pressure that releases is equivalent to 3 to 60% of former maximum pressure; be preferably 3 to 30%, its feature also is: under the pressure of remnants, and heating system; make that the discharge temperature of tobacco is in 10 ℃ to 80 ℃ scope after the complete pressure release.

2. the method for claim 1, it is characterized in that: the original water content of tobacco-containing material is in 10 to 14wt% scope.

3. as the described method of claim 1 to 2, it is characterized in that: under residual pressure, improve system temperature by the retention time.

4. as the described method of claim 1 to 3, it is characterized in that: under residual pressure,, improve the temperature of system with the mode of heat exchanger recyclegas.

5. as the described method of claim 1 to 4, it is characterized in that: under residual pressure,, improve the temperature of system with the mode that transmits heated air.

6. as the described method of claim 1 to 5, it is characterized in that: the pressure release that drops to maintenance stage pressure from the maximum pressure of every kind of situation was carried out in 20 seconds to 5 minutes the time interval.

7. as the described method of claim 1 to 6, it is characterized in that: the pressure release of residual pressure was carried out in 3 seconds to 3 minutes the time interval.

8. as the described method of claim 1 to 7, it is characterized in that: repeatedly same tobacco-containing material is carried out HIGH PRESSURE TREATMENT or HIGH PRESSURE TREATMENT and post bake processing continuously.

9. as the described method of claim 1 to 8, it is characterized in that: with saturated vapor tobacco-containing material is carried out post bake and handle.