JPH06209751A - Method of adjusting moisture content of organic material - Google Patents

Abstract

PURPOSE: To provide a recontrol method for tobacco without intensively reducing the CV of tobacco in balanced state or without intensively degrading tobacco, and a drying method for tobacco while preventing the CV of tobacco from being intensively changed in balanced state or preventing tobacco from being intensively degraded. CONSTITUTION: The tobacco to be recontrolled is brought into contact with an air current having a relative humidity closer to the balanced state of tobacco. With the increase of OV content in tobacco, the relative humidity of air current in contact with tobacco is increased so as to be operated upon the recontrol of tobacco. The tobacco to be dried is let be in contact with an air current having relative humidity closer to or lower than the balanced state of tobacco. With the decrease of OV content in tobacco, the relative humidity of air current in contact with tobacco is decreased so as to be operated upon the dry of tobacco. The tobacco can be successfully recontrolled or dried in continuous manner while using an independent piled-up helical conveyer.

Description

Detailed Description of the Invention

The present invention relates to a method of reordering tobacco or other hygroscopic substances such as pharmaceuticals and agricultural products including, but not limited to fruits, vegetables, grains, coffee, and tea. It relates to a method of increasing its water content and then drying. More particularly, the invention relates to a method of moistening or drying these materials with air having a controlled humidity.

It has long been recognized in the art that it is desirable to control the water content of various organic materials, including tobacco. For example, the moisture content of tobacco processed into useful products has been changed many times. As a processing step, for example, removal of the stem,
Cutting, blending ingredients, adding fragrance, developing (expa
nsion) and shaping into cigarettes, but each processing step requires a certain optimum moisture content level, which must be carefully controlled to ensure the highest quality for tobacco and other hygroscopic organic materials. I won't. Moreover, the modalities of changing the moisture content of tobacco can have a lasting effect on the physical, chemical and subjective characteristics of the final product. Therefore, the method used to change the water content of organic materials such as tobacco is important.

Reconditioning of deployed tobacco is a particularly demanding process. Generally, tobacco obtained from the expansion process has a water content of 6
% And often less than 3%. With such a low water content, tobacco is very fragile. Moreover, the deployed structure of the tobacco is susceptible to destruction when reconditioning, ie returning the tobacco in whole or in part to its undeployed state. This disruption results in a loss of fill force, thus reducing the benefits provided by the deployment process.

Various means have been used to recondition spread tobacco. The most common method is generally to give the tobacco a spray of water while tumbling the tobacco in a rotating cylinder. Another method is to use saturated steam as the reconditioning medium. Yet another method is to blow high humidity air through a moving bed of tobacco on a conveyor, as disclosed in U.S. Pat. No. 4,178,946.

It has been found that none of the above methods are completely satisfactory for use on an expanded tobacco. Tumbling tobacco in the spray cylinder leads to breakage of brittle, expanded tobacco. Direct contact with liquid water tends to destroy the structure of the expanded tobacco. Reconditioning with steam also results in destruction of the structure of the deployed tobacco. This is partly due to the high temperatures in the vapor environment, but exposing tobacco deployed in a gas environment that causes condensation of water, such as a water vapor or humid air environment, destroys the structure. It

One method that has been used to avoid these difficulties is to place the dried and spread tobacco in a chamber containing air at the desired humidity level,
It is a method of equilibrating tobacco in a chamber for 24-48 hours. The velocity of the air passing through the chamber is kept very low, typically about 25 feet per
Up to the minute. With this method, little or no destruction of the structure of the deployed tobacco occurs. However, since it requires a long period of 24 to 48 hours, its use has been limited to test rooms.

Attempts have been made to reduce the residence time required for such equilibration methods by increasing the velocity of air. These methods have been unsuccessful because of the following: That is, the inability to replicate the retention of fill force found in slow laboratory equilibration, the size of the conveyor required to carry tobacco to accommodate the long residence times required, and the tobacco products present on such conveyors. Non-uniform water content in US Pat.
This is due to the occurrence of a fire in these devices described in No. 357.

The use of drying as a means of controlling the water content during tobacco processing is equally important as a means of reconditioning. Drying tobacco can cause both physical and chemical changes that affect the physical and subjective quality of the product. Therefore, the method of drying tobacco is very important.

There are two types of dryers commonly used in the tobacco industry: rotary dryers and belt or apron dryers. Pneumatic dryers are also sometimes used. The particular dryer used is selected to obtain the required drying action. Belt or apron driers, for example, are commonly used for strip tobacco, while rotary driers are used for cut tobacco. Both rotary dryers and belt dryers are used to dry the midbone.

In a belt dryer, tobacco is spread over a perforated belt, allowing air to pass through the belt and the tobacco layer up or down. Tobacco often dries unevenly as channels form in the tobacco layer and the dry air locally bypasses the tobacco.

Most tumble dryers used in the tobacco industry are lined with steam coils and either indirectly or directly heat dried, depending on whether heat is applied to the outside or inside of the dryer shell containing the tobacco. Function as a machine. Further, the tumble dryer operates in co-flow if the tobacco and air are flowing in the same direction, or in reverse flow if the tobacco and air are flowing in opposite directions.
Spin drying must be carefully controlled to avoid overdrying. When over-dried, both chemical changes and unnecessary tearing due to rotational movement occur. Further, if the drying is too fast, an impermeable layer is formed on the outer surface of the cigarette, which makes it difficult for moisture inside the cigarette to diffuse to the surface. The formation of such a layer results in a slow drying rate and uneven drying.

When a tumble dryer or belt dryer is used to dry tobacco, it is heat treated to cause physical and chemical changes to the tobacco. These changes are not always desirable, but are done to remove moisture from the tobacco. In common tobacco applications, it is necessary to dry the tobacco for a limited amount of time, which dictates the heat treatment of the drying process and prevents optimization of the heat treatment from being constrained by drying.

The invention is defined by the independent claims, which are set forth below.

In embodiments of the present invention, tobacco, or other suitable hygroscopic produce, including but not limited to fruits, vegetables, grains, coffee or tea, is fragile from the spreading process. Even cigarettes have the advantage that they can be reconditioned or dried with little or no tear. Further, the present invention has the advantage of reconditioning a deployed tobacco with little or no loss of the structure of the deployed tobacco, and to the extent that tobacco or other suitable hygroscopic organic material is It is possible to dry under atmospheric pressure, for example at a selected temperature, without the use of reduced pressure, and the heat treatment applied can be controlled during the process to a degree unattainable by conventional tobacco drying processes.

In a preferred method of practicing the invention,
Changes in the water content of tobacco or other suitable organic material are affected by contacting the tobacco with air having a carefully controlled relative humidity above or below the equilibrium relative humidity of the organic material in contact. The relative humidity of air is
In order to maintain a controlled difference between the relative humidity of the air and the equilibrium relative humidity of the organic material with which the air is in contact, a suitable continuous increase or decrease during processing. Careful and continuous control of relative humidity minimizes structural changes in tobacco by controlling the mass transfer rate of water between the organic material and its environment. Utilizing relative humidity as the main driving force for mass transfer of moisture allows the heat treatment to be controlled independently. The process of the invention can be carried out batchwise or continuously. Furthermore, the method of the present invention can be carried out without the use of a rotating cylinder and thus without the breaks caused by using a cylinder.

The present invention is directed to tobacco or pharmaceutical products and, without limitation, fruits, vegetables, cereals, while minimizing breakage of the tobacco being processed, changes in physical structure or heat-driven changes in chemical composition. , Other suitable hygroscopic organic materials, such as agricultural products, including coffee, and teas. More particularly, the present invention relates to using air with controlled humidity to recondition or dry tobacco or other suitable hygroscopic organic material. The water content of tobacco or other suitable hygroscopic organic material is increased or decreased by appropriately, gradually and continuously increasing or decreasing the relative humidity of the air in contact with the tobacco or other suitable hygroscopic organic material. . According to this method
Moisture transfer is controlled and other process variables such as temperature, air velocity and air pressure can be separately optimized.

Examples Examples of methods of practicing the present invention and preferred embodiments thereof will now be described with reference to the accompanying drawings. Two methods commonly used to characterize the physical structure of tobacco are cylinder volume (CV) and specific volume (SV). These measurements are of particular value in assessing the benefits of the method of the present invention for reconditioning tobacco.

Cylinder volume (CV) Filled tobacco (tobacco filler) is 20 if not yet expanded.
g, 10g if unfolded, Den 6cm in diameter
Put in simeter cylinder, Model No. DD-60. This is the Heinr. Borgwaldt Company (Heinr. Bo
rgwaldt GmbH), West Germany 54, Hamburg 2000, PO Box 540702, Schnackenburgallee No. 15). A 5.6 cm diameter, 2 kg piston is placed on the cigarette in the cylinder. The volume of compressed tobacco is read and divided by the weight of the tobacco sample to give the cylinder volume as cc / g. This test measures the apparent volume of a given weight of filled tobacco. The resulting volume of filled tobacco is reported as the cylinder volume. This test is conducted at 75 ° F and 60% R
Samples are preconditioned in this environment for 24-48 hours unless otherwise noted under standard environmental conditions of H.

Specific Volume (SV) The term "specific volume" is a unit used to measure the volume occupied by a solid object, such as a cigarette, using the Archimedes principle of fluid exclusion. The specific volume of an object is measured by taking the reciprocal of its true density. The specific volume is represented by "cc / g". Both the mercury porosimetry and the helium specific gravity method have been found to be suitable for making this measurement, and the test results are well correlated. When using the helium specific gravity method, the tobacco weighed sample is “as is”, dried at 100 ° C. for 3 hours, or equilibrated to the Quantachrome Penta-Pycnom
eter Model 2042-1 (Quantachrome Corporati
on, USA, New York, Saiyo Set, Airy Way, 5 products). The cell is then purged with helium and pressurized. The volume of helium displaced by the cigarette is compared to the volume of helium required to fill an empty sample cell. Tobacco volume is measured based on the basic principles of the ideal gas law. Specific volume, as used throughout this application, unless otherwise indicated, was obtained using the same tobacco sample used to measure OV, ie, tobacco that was dried for 3 hours in a circulating air oven controlled at 100 ° C. It was measured.

The water content used in this application is considered to be equal to the oven volatiles content (OV). This is because the volatile content other than water is up to about 0.9% of the weight of tobacco. Oven volatiles are simply measured at 100 ° C
The tobacco weight loss is only measured after 3 hours of exposure in a controlled-circulation air oven. The weight loss as a percentage of the initial weight is the oven volatile content.

"Sieving test method" means a method for measuring the cut length distribution of cut and filled tobacco. This test method is often used as an indicator of the reduction in cut length during processing. Filled tobacco, 150 ± 20g when undeveloped
If it is unfolded, 100 ± 10 g is weighed and placed in a shaker. This shaker has a diameter of 1
2 inch series of round screen trays (WS Tyler
Inc. namely Combustion Engineering Inc. Screen
It uses a small company of Division, Mentor, Ohio, 44060, USA), but it meets the standards of ASTM (American Society for Testing and Materials). Standard screen sizes for sieving trays are 6 mesh, 12 mesh,
20 mesh and 35 mesh. This device has a shaking distance (stroke) of about 1 to 0.5 inch and a shaking speed of 350 ± 5 rpm. The shaker stirs the tobacco for 5 minutes, separating the sample into different particle size ranges. Each particle size range is weighed to obtain a sample particle size distribution.

Laboratory tests have shown that attempts to rapidly recondition tobacco by exposing it to high humidity air results in a reduction in CV. It has also been found that CV decreases when condensation or over-wetting occurs within the developed tobacco layer. Condensation occurs when moist air contacts tobacco at a temperature below the dew point of the moist air. Excessive wetting may occur when moisture fluctuations occur in the tobacco layer due to uneven exposure to humid air. Therefore, a moist air reconditioning system must be operated at a relatively low speed with sufficient control of the relative humidity of the air, the temperature of the air, the flow and pressure of the air through the bed of tobacco to be successful. I won't. This is best accomplished by gradually increasing the moisture content of the moist air passing through the tobacco in a manner such that the tobacco is exposed to an air stream that is approximately in equilibrium with the tobacco.

In FIG. 1, the line ABC is the isothermal curve for a typical developed bright tobacco at 75 ° F. This isotherm shows the relationship between the tobacco OV and the RH of the air surrounding the tobacco in equilibrium at a given temperature. Therefore point B is 6 at 75 ° F.
At 0% RH, this developed tobacco sample shows an equilibrium OV of about 11.7%. Line DEF of Figure 1
Shows a graph of typical RH of tobacco being reconditioned according to the present invention. The line GEF of FIG. 1 shows another graph of RH that was found to be satisfactory.
Line HF in FIG. 1 shows the general path of the prior art, such as the reconditioning of a test chamber in an equilibration chamber at a very low air velocity. Line IJ in FIG. 1 illustrates the use of the present invention to dry tobacco.

FIG. 1 illustrates that a cigarette has an OV of about 6.5% when RH is in equilibrium with about 30% air to about 11.% when RH is equilibrating with air of about 60%. Reconditioning to an OV of 7% does not mean that the cigarette is directly exposed to air with a RH of 60%, but a cigarette with an R of about 60%.
It is shown to be achieved by exposing the tobacco to air that has been hydrated in increments of about 40% RH over time until H is reached. When the reconditioning is carried out under these slowly changing conditions, the mass transfer between the air stream and the tobacco is relatively slow due to the small driving force and the deployed tobacco structure is maintained. Water content from about 40% RH to about 62% RH until reaching about 40%
By exposing the tobacco to a slightly elevated air over about 60 minutes, the expanded tobacco can be reconditioned without loss of CV. According to this method, the reconditioning step can be completed with less total time required and with little change in the structure of the expanded tobacco. Thus, the lines DEF and GEF shown in FIG. 1 each represent an effective embodiment of the invention for reconditioning tobacco.

In FIG. 1, the near equilibrium condition between the air flow and the tobacco is indicated by the line segment EF and the line ABC. When the OV of a cigarette is less than about 7%, the difference between the relative humidity of the air in equilibrium with the cigarette and the relative humidity of the moist air stream used for reconditioning, even if significantly large, adversely affects the filling capacity of the cigarette. You will see that it does not give. Also, when the OV of the tobacco is about 7.5% to about 11.5%, the relative humidity of the moist air stream used for reconditioning is about 2% to about 8% of the relative humidity of the air in equilibrium with the tobacco.
It will also be appreciated that it may be high and that deviations from the equilibrium corresponding to low tobacco OVs will not adversely affect the packing force of the tobacco.

No loss of tobacco CV was observed when the present invention was used to dry tobacco. This is
It has also been found to be true when the relative humidity of the dry air stream is significantly lower than the relative humidity of the air in equilibrium with the tobacco, ie when the relative humidity of the dry air stream is lower than in the equilibrium of the tobacco. Therefore, line IJ of FIG. 1 shows only one of the many routes that can be used when drying tobacco according to the present invention.

The present invention can be practiced as either a batch or continuous process. When the present invention is practiced as a batch reconditioning step, the relative humidity of the air stream contacting the tobacco is increased over time to continuously increase the water content of the tobacco. This can be accomplished in an environmental chamber as shown in FIG. The tobacco to be reconditioned is placed in a tray with a screen at the bottom in the environmental chamber at a layer depth of about 2 inches,
A controlled flow of moist air is passed down the tobacco. Chambers in the size range of about 20 ft ³ to about 80 ft ³ (Parameter Generation and Control, Inc.
Inc., West Carolina, USA 28711, Black Mountain, West, 1104 Old US 7
0 products) were used in some tests. The environmental chamber is equipped with a microprocessor that can control the inclination of the moist air condition in the chamber. The test was conducted as follows. That is, RH is about 30% R
From a low initial level such as H and a high initial level such as about 52% RH, about 59% over about 30 minutes to about 90 minutes
The dried and expanded tobacco was readjusted from about 2% of the initial OV level to about 11.5% of the final OV level by stepwise raising to a final RH level of ˜65%. Air velocity is about 50 ft / min to about 200 ft / min
Utilized the range of minutes. RH and temperature measurements are Thunder
model 4A-1 measuring device (Thunder Scientific Corp.
Co., S.E., New Mexico 87123, USA
Albuquerque, Wyoming 623 product). Air velocity is Alnor Thermo Anemometer model
8525 (Alnor Instrument Co., Lynne Abnew, 755, Skokee, Illinois, USA 60066)
5 N. Products). Relative humidity from a starting value as high as about 52% to a final RH as high as about 62%
The test was conducted by raising the value to a value in a short time of about 40 minutes, and the same cigarette was kept at a slow speed for 24 to 48 hours in an environment-controlled room in which air was maintained at 60% RH and 75 ° F. Tobacco was reconditioned with sufficient CV retention as compared to passing and reconditioning. This type of RH rise was successful at high moist air velocities of about 200 ft / min and temperatures of about 75 ° F to 90 ° F. Expanded tobacco reconditioned in this manner had minimal, if any, CV loss compared to expanded tobacco reconditioned in an environmentally controlled room.

The present invention provides the Frigosca as shown in FIG. 3a.
ndia self-stacking spiral carrier
It can be most effectively carried out as a continuous method using a transport machine). This device is a special modification of the Model GCP spiral freezer supplied by Frigoscandia Food Process Systems AB, Helsingborg, Sweden. Conveyor 1 for dry tobacco to be reconditioned
3 into the device 10 and through the spiral-shaped device 10 is carried from the bottom to the top of the spiral-shaped stack 14 shown in the figure and exits the tobacco outlet 11 after being reconditioned. The moist air is fed from the moist air inlet 15 to the spiral stack 14
The tobacco passes through the bottom of the stack and is blown down through the moist air outlet 16, where the moist air flows in a direction approximately opposite to the direction of flow of the tobacco, i.e. the majority of the moist air flow is downwards from the top of the stack. Through the layers of tobacco layers, while the tobacco moves upwards along the spiral path of the conveyor. A portion of the moist air flows along a spiral path that is the exact opposite path from the top to the bottom of the conveyor stack. These types of airflows are shown in Figure 3b. This arrangement effectively replicates the increase in RH obtained with the device of FIG.

FIG. 3b is a partial cross-sectional view of the spiral conveyor stack 14 shown in FIG. 3a, showing the paths of airflows 20 and 22 relative to the path of the tobacco layer 21. Figure 3
Air streams 20 and 22 are flowing downwardly from the top of the stack as shown in b. Tobacco is shown flowing from the bottom to the top of the device and moving from right to left in FIG. 3b as it progresses upwards by the spiral conveyor stack 14. While most of the air stream 20 is flowing in a direction generally opposite to the tobacco path, it passes through the layers of tobacco layers 21 into contact with the tobacco layer at the level directly below, while a small portion of the air stream 22 is , Above the tobacco layer 21 in a direction opposite to the path of the tobacco layer 21. Airflow in this part 2
2 then passes through the tobacco layer 21.

When performing reconditioning, the key to successful practice of the present invention is to provide a means of regularly increasing the relative humidity of the air in contact with the tobacco as the tobacco OV increases. The Frigoscandia freestanding stacking spiral conveyor, due to its freestanding stacking design, allows most of the airflow to pass down multiple levels of conveyors carrying conveyors (conveyor stacks). By directing the tobacco to the bottom of the conveyor stack and moist air to the top of the stack, the overall flow of air and tobacco is approximately opposite. This near-reverse flow imparts a natural continuous RH gradient to the air in contact with the tobacco. This is because the air is progressively dehydrated as it moves downwards through the tobacco hierarchy undergoing the reconditioning process. Similar conditions to those used in batch laboratory RH tilt readjustment experiments by careful selection of conveyor belt speed, air and tobacco flow rates, and incoming air temperature and RH controls. Can approach a continuous basis. About 40 minutes to about 8 to recondition a developed cigarette with 3% OV at about 150 pounds / hour
Residence time of 0 minutes and about 1000 ft ³ / min (CFM)
About 75 ° F to about 95 ° at an air flow rate of about 2500 CFM
Improved Frigoscandi by the speed of the belt to provide an air condition with an inlet relative humidity of about 61% to about 64% at F.
a Significant C of tobacco using GCP42 helix device
It has been found that it can be readjusted sufficiently without V loss or non-negligible tearing.

A device for recording relative humidity over time, such as a Model 29-03 RH / Temperature Recorder (a product of Rustrak Instruments Co., Inc., E-Greenwich, RI, USA), was used to recycle the cigarette. Actuated through the Frigoscandia device while adjusting. These devices showed that the relative humidity of the air increased regularly as one went up the spiral stack. That is,
Initial R at the bottom of the stack where the cigarettes are the driest
Recorded H values range from about 35% to about 45%, with about 62% at the top of the stack where tobacco is most well reconditioned.

FIG. 6 is a representative curve of RH versus time obtained with the Rustrak instrument. Air RH% in contact with the tobacco layer
The relationship with time is shown in FIG. Tobacco with an initial OV of about 3% entered the spiral reconditioning device and was in contact with air with an RH of about 43% (point A in Figure 6). Figure 6 shows the RH of the air in contact with the tobacco as it is advanced by the spiral reconditioning device.
Indicates an increase from about 43% to about 62% at the exit of the device (point B in FIG. 6). The tobacco had an OV of about 11% as it exited the spiral reconditioning device. The RH of the air entering the spiral reconditioner was controlled so that the CV of the reconditioned tobacco was not significantly lost.

Other means of providing air with a slope RH as shown in FIG. 4 can also be used to practice the present invention on a continuous basis. According to FIG. 4, the tobacco rides on the conveyor 43 into the device at the tobacco inlet 40 and exits at the tobacco outlet 41. Regularly increasing relative humidity air is blown upwards or downwards through the tobacco layer 42 into a number of zones 44 to reproduce the tilted RH effect in the apparatus of FIG. This tilted RH effect can be achieved by moving air from a single source, in a spiral fashion, from right to left in FIG. 4 to provide an air flow approximately opposite to the direction of tobacco movement. Thus, the air exiting a given area becomes the inlet air for the adjacent area to its left.

To carry out the method of the invention, tobacco, such as aged whole tobacco mesophyll, tobacco in cut or chopped form, expanded or unexpanded tobacco, or mid-bone or reconstituted tobacco. Selected portions of may be processed. The process can be applied to any or all of the above with or without perfume. In the special case of drying tobacco, unexpanded cut-filled tobacco is used in a modified Frigoscandia self-supporting stacking spiral conveyor in a substantially counter-current flow at about room temperature at about 21 ° C.
It has been found that it is possible to continuously dry from a tobacco water content of% OV to an OV of about 15% in about 1 hour. In this case, air entered the top of the unit at about 85 ° F and about 58% RH and exited at about 77 ° F and about 68% RH. Drying was achieved with little or no heat treatment of the tobacco.

Alternatively, the method of the present invention may be applied to tobacco that is substantially above room temperature, eg, about 200 ° F. to about 250 °
Can be used to dry F tobacco. When drying tobacco within the above temperature range, the RH and temperature of the dry air is adjusted to provide the appropriate conditions for carrying out the method of the present invention.

Similar to reconditioning tobacco, drying
The final air water content is set below the water content required to reach the tobacco to its desired final air moisture level, thus increasing the air-tobacco moisture gradient and thus the driving force that causes drying. Has been found to be best achieved in the shortest time. Unlike the process of reconditioning, the final water content of the air stream may be maintained at a level after drying that is much lower than the level equilibrated with the desired OV level of tobacco.

Experiment 1 In order to show the advantage of performing reconditioning by slowly measuring and giving water to the dried and spread tobacco as compared with the spray cylinder reconditioning method, 20 g of a filled tobacco sample was used. Placed in a sealed desiccator. This sample was previously impregnated with liquid carbon dioxide and developed in a development tower at 550 ° F. The OV of the developed filled tobacco was 3.4%. It was calculated that about 1.89 g of water was required to increase the OV content of this sample to 11.5%. This amount of water was placed in a small glass bottle with a rubber stopper. The stopper is equipped with a glass tube having a 1/8 inch inner diameter extending through the stopper. This bottle was also sealed in the desiccator. After 9 days, all the water was absorbed by the tobacco in the desiccator. When this tobacco was analyzed, the OV as it was (as is OV) was about 11.
It was found to be 5%. As used herein, the term "as is" is passed through an environmental chamber containing air held at 60% RH and 75 ° F at low velocity for 24-48 hours to allow equilibration within the chamber. It means the cigarette before letting it go. This equilibration method generally uses C
Used as a means to bring tobacco to a standard condition before performing V, SV and sieve tests. After the equilibration of this standard, the tobacco reconditioned with a desiccator has an OV of about 1
At 1.6%, the CV was about 9.5 cc / g and the SV was about 2.9 cc / g. For comparison, a second sample of the same tobacco was readjusted by placing it directly into the equilibration chamber and equilibrating under standard conditions. The equilibrated OV was about 11.3%, which was equal to the CV. The SVs were about 9.4 cc / g and about 2.7 cc / g, respectively. A third sample of the developed filled tobacco was readjusted in a spray cylinder to a neat OV of about 11.5%. After equilibration, this sample had an equilibrium OV of about 11.6%, a CV of about 8.5 cc / g and an SV of about 1.9 cc / g.

As can be seen from the data in Table 1, tobacco samples reconditioned in a desiccator by slowly feeding a metered amount of water had significantly improved equilibrium CV and equilibrium SV compared to spray reconditioned samples. I showed that.

[0039]

[Table 1]

A second set of experiments was conducted using an environmental chamber to recondition the filled tobacco. For this purpose, Parameter Generation and Control (PGC)
A chamber was used. This chamber is called Parameter Ge
Micro-Pro supplied by neration and Control Inc.
It was equipped with a 2000 microprocessor, which was able to control the RH tilt of the conditions in the chamber.

Experiment 2 Bright tobacc expanded with liquid carbon dioxide impregnated under conditions similar to those described in Experiment 1.
o) About 3 pounds were placed in the tray at a layer depth of about 2 inches. The tray had seamless sides and a bottom of screen mesh and was placed in an environmental chamber. The sample is then RH at about 75 ° F. from about 36% of the initial to 60% of the final.
Readjustment was performed over about 1 hour with air raised to%. Air was passed down the tobacco layer at a rate of about 45 ft / min. This experiment was then repeated for 3 hours, 6 hours and 1 hour.
Repeated over 2 hours. The results obtained are shown in Table 2 and show that the readjustment rate affects the CV and SV of tobacco under these experimental conditions when the RH rise time is up to about 6 hours. It was observed that the slower the readjustment rate, the higher the CV and SV. Further, the reconditioning of the present invention results in a CV of at least about 1 cc / g and an SV of at least about 0. 0 greater than the value measured for the spray cylinder reconditioned tobacco.
2cc / g increase. However, it has been found that most of this advantage is achieved with an RH rise time of only 1 hour.

[0042]

[Table 2]

Experiment 3 A laboratory test was conducted on the effect of both reconditioning rate and temperature on CV and SV of tobacco. Seven sets of tests were conducted with tobacco impregnated with carbon dioxide and then developed in a development tower at about 550 ° F. The spread tobacco was readjusted by the following method. (1) In an environmental chamber of 60% RH and 75 ° F., air is passed through the tobacco at a rate of about 25 ft / min to equilibrate for 24 hours. (2) Spray water to increase OV to about 7.5%,
Then, as in (1) above, equilibration is carried out at 60% RH and 75 ° F. (3) Spray water to increase OV to about 7.5%,
Then do a final readjustment in the spray cylinder. (4) Spray water to bring OV to about 7.5%, then RH
Is performed with moist air raised from about 46% at the beginning to about 60% at the end. And (5) with humid air having RH raised from about 46% to about 60%.

Reconditioning with moist air was carried out in a PGC environmental chamber equipped with a microprocessor controlling the rise in RH at selected times. The following conditions were selected. (1) RH rise time: 30, 60 and 90 minutes; (2) Air temperature: 75 ° F and 95 ° F; (3) Air velocity: Approximately 4 when passing upward through the tobacco layer.
5 ft / min and 17 when passing down the tobacco layer
5 ft / min; and (4) Tobacco layer thickness: 2 inches; All cigarettes used for reconditioning, except by spray cylinder, are collected at the tower outlet after deployment and doubled until reconditioning Sealed in a plastic bag. As a result, the tobacco was cooled from the temperature at the outlet of the developing tower of about 200 ° F. to room temperature before the reconditioning. About 95 cigarettes
When readjusting by raising RH at ° F, leave it in a sealed bag, preheat sufficiently to avoid condensation when contacting with moist air, and then expose to RH raising conditions. . The data for these tests are shown in Tables 3a-3e.

[0045]

[Table 3]

[0046]

[Table 4]

[0047]

[Table 5]

[0048]

[Table 6]

[0049]

[Table 7]

The data shown in Tables 3a-3e show that the gain of CV is about 0.5 cc / g to about 1 cc / g and the SV is about 0.3.
Gains of cc / g to about 0.4 cc / g are compared to refrigerated hot cigarettes emerging from the expansion tower with cylinder spray, i.e., chilled tobacco, i.e., about 75 ° F to about 95 ° F.
It can be achieved by increasing the RH and reconditioning of tobacco up to. It has been found that reconditioning by raising RH directly from the OV at the exit of the column is preferable to first spraying tobacco to increase its OV content to about 7% and then reconditioning to increase RH. About 46%
There is no significant difference in the CV or SV of tobacco compared to the case where the RH was raised and re-adjusted by using the moist air having the initial RH of 30% and the case where the RH was raised from the initial RH of about 30% and re-adjusted. I couldn't see it. Further, no significant difference was observed in the CV or SV of tobacco in the tobacco which was readjusted by raising the RH in the period of about 60 minutes or about 90 minutes. Tobacco is about 175 ft / min to about 235 ft / min.
It can be readjusted by the motion of air passing down the tobacco layer at a rate of minutes, or air passing up the tobacco layer at a rate of up to about 45 ft / min, with no significant difference in CV or SV. It was observed that it was not observed. On top of that, by re-adjusting by raising RH, it is possible to obtain CV and SV that are equal or superior to those of cigarettes re-conditioned after leaving the expansion tower and directly placed in an environmental chamber of 60% RH and 75 ° F. I understood. Finally, if you spray water to increase the OV to about 7.5% and then readjust it by increasing RH with moist air,
It was observed that superior CV and SV were obtained compared to spraying followed by final readjustment in the spray cylinder.

Experiment 4 A test was conducted to determine the effect of air flow and air velocity on tobacco entrainment, channeling and compaction.
These tests were performed using two PGC environmental chambers. The actual air movement in both chambers was approximately 500 CFM. The movement of the air is the movement passing upward through the tobacco layer in one PGC chamber,
In the other PGC chamber, the movement was to pass downward through the tobacco layer. Tobacco samples were placed in a top open tray (5 "x 5 3/4") with a depth of 2 inches and a bottom of screen mesh and a seamless side of height 4 inches. These trays were placed on shelves in the environmental chamber. Air was passed through the sample by covering the area of the shelf that was not loaded with trays with cardboard and sealing the crevices with tape. Air velocities were varied by changing the number of sample vessels through which the air passed. The tobacco used in these tests was impregnated with carbon dioxide and developed at about 550 ° F. In the first step, the tobacco was reconditioned to about 8% OV by spraying with water immediately after deployment. The conditions in the chamber during the test were controlled at about 75 ° F and about 60% RH. A vane anemometer (Model LCA, a product of Airflow Instrumentation, Inc., Frederick, MD, USA) is used to measure air velocity.
6000) and hot-wire anemometer (Alnor Instrument Comp
any, Thermometer M product of Skokee, Illinois, USA
odel 8525) was used. These instruments were placed directly above or below the sample for upward and downward air movements, respectively.

When the air moves upward, it is about 26 ft.
A slight lifting of the tobacco was observed as soon as air was expelled at a low average rate such as / min. At this time, small air channels are created and then the tobacco settles. Due to these channels, the air flow rate was found to be highly non-uniform across the tobacco layer (average flow rate about 26).
About 22 ft / min to about 45 ft / min relative to ft / min).
It is clear that increasing the average air flow increases channeling, with significant tobacco "blow up" observed above 45 ft / min, followed by significant channeling of the tobacco layer. Happened.

As air travels downward, some compression and a reduction in air velocity due to passage through the tobacco layer was observed at all velocities tested. The results are shown in Table 4. At an initial velocity of about 192 ft / min, the depth of the tobacco layer compressed by about 28%, resulting in a reduction of the air velocity through the tobacco layer to about 141 ft / min. If the initial air velocity is less than about 141 ft / min, the compression of the tobacco layer is
The initial air velocity was about 1/2 of the compression observed at about 192 ft / min, and the air flow rate through the tobacco layer was significantly reduced.

[0054]

[Table 8]

Based on the above tests, it has been found that it is possible to readjust by increasing RH, preferably under the following conditions. (a) Time: about 60 minutes to about 90 minutes; (b) RH: about 30% to about 45% initial RH to about 60%.
Up to a final RH of about 64%; (c) temperature: about 75 ° F. to about 95 ° F .; (d) air flow: upward air flow of velocity up to about 45 ft / min or up to about 235 ft / min. Air flow below velocity;

Experiment 5 Carbon dioxide was impregnated according to the method described in Cho et al., US patent application Ser. No. 07/717067, assigned in the same manner as the present invention in the copending application and then described in the above examples. Bright species (brigh
t) About 1 mixture of tobacco and burley tobacco
Fifty pounds / hour was retrofitted by passing it through a cooling conveyor, reducing its temperature from about 200 ° F to about 85 ° F.
The Frigoscandia Model GCP 42 was sent to a free-standing stacking helix. The tobacco flow through the spiral device was from bottom to top. The air flow was from the top of the device to the bottom, with the tobacco flowing in approximately the opposite direction to the air. With this device, the air was continuously dehydrated by the tobacco, so that the tobacco was readjusted by increasing the RH. Tobacco that entered the process at about 3% OV exited the process at about 11% OV. The equilibrated CV of the feed was about 10.53 cc / g while the equilibrated CV of the reconditioned feed was about 10.46 cc / g. This indicates that the tobacco packing power is not significantly lost through the reconditioning process, ie, the packing power is not statistically significant when tested by standard ANOVA. Moreover, the size of the tobacco pieces did not decrease appreciably during the reconditioning process as a result of the sieving test.

Experiment 6 A series of experiments were conducted using various cigarettes developed at different tower temperatures and reconditioned by the method of the present invention. In each experiment, approximately 150 lbs / hr of tobacco, based on the reconditioned tobacco mass, was reconditioned with the modified Frigoscandia freestanding stacking helix device described in Experiment 5. The inlet air of this reconditioner was set at about 85 ° F. and about 62% relative humidity. The air exiting the reconditioning device is generally about 90 ° F to about 95 °.
At F, the relative humidity was about 40% to about 45%. As shown in Table 5, tobacco reconditioned according to the method of the present invention did not show any significant loss of filling power.

[0058]

[Table 9]

Run 7 About 200 pounds per hour of bright tobacco with an OV of about 21.6% was fed to a modified Frigoscandia freestanding stacking helix device as described in Run 5, which operates as a dryer. The tobacco flow through the spiral dryer was from bottom to top. The air flow was from the top of the device to the bottom, with the tobacco flowing in approximately the opposite direction to the air. Tobacco was continuously dried using air having an inlet temperature of about 95 ° F. and an inlet RH of about 35% to an OV of about 12.2% with a residence time of about 60 minutes. The air exiting the dryer was about 62% RH at about 83 ° F. The tobacco coming out of the dryer was cold to the touch and had an estimated temperature of about 75 ° F, indicating that the tobacco was not substantially heat treated. The CV of the equilibrated tobacco was not changed by the drying process.
This particular drying experiment was designed to minimize heat treatment. Similar drying results could be obtained using higher temperatures to perform the heat treatment to a controlled degree.

Although the present invention has been presented and described in detail with reference to preferred embodiments, it is understood that various changes in form and detail may be made without departing from the spirit and scope of the invention. Those of ordinary skill in the art will appreciate.

[Brief description of drawings]

FIG. 1 is a graph of relative humidity (RH)% of air versus water content or OV of tobacco.

FIG. 2 is a schematic diagram of a laboratory apparatus for reconditioning a hygroscopic organic material according to the present invention by raising the RH of air over time.

FIG. 3 a) is a cutaway view of a typical apparatus used to carry out the present invention continuously, b) is a cross-sectional view of a portion of the spiral conveyor stack shown in a), a hygroscopic organic 3 shows the path of air flow relative to the path of material.

FIG. 4 is a schematic diagram of another apparatus suitable for practicing the present invention on a continuous basis.

FIG. 5 is a block diagram showing a case where the present invention is applied to a readjustment process.

FIG. 6 is a representative graph of RH vs. time for air in contact with a cigarette, which was obtained during reconditioning with the device shown in FIG. 3a.

[Explanation of symbols]

 10 Frigoscandia Spiral Stack Conveyor Equipment 11 Tobacco Outlet 13,43 Conveyor 14 Spiral Conveyor Stack 15 Wet Air Inlet 16 Wet Air Outlet 20,22 Air Flow 21,42 Tobacco Bed 40 Tobacco Inlet 41 Tobacco Outlet 44 Area

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical indication location A23F 3/22 8114-4B 5/28 8114-4B (72) Inventor John Clamp The・ Third United States 23228 Virginia, Litchmond, Essex, Road 2206 (72) Inventor Eugene B. Fisher 23831 Virginia, United States, Chester, Nightingale, Drive 12800

Claims (36)

[Claims] 1. A flow of (a) contacting an organic material with an air flow having a relative humidity close to its equilibrium state, and (b) an air flow contacting the organic material to increase the water content of the organic material. Increasing the relative humidity of the air stream contacting the organic material in such a manner as to maintain the relative humidity of the organic material near the equilibrium state of the organic material until the desired water content of the organic material is achieved. A method of increasing the water content of a material. 2. The equilibrium CV of the organic material after step (b) is
The method of claim 1 wherein the equilibrium CV of the organic material prior to step (a) is not significantly less than. 3. A step of (a) placing an organic material on a conveyor to form a layer of the organic material, (b) the organic material and an air flow flowing in a path substantially opposite to the path of the organic material layer. Contacting, and (c) transferring a portion of the water content of the air stream to the organic material in such a manner that the relative humidity of the air stream contacting the organic material is maintained near the equilibrium state of the organic material, Consisting of an organic material, the air stream being progressively dehydrated and the organic material being gradually hydrated as the air stream flows substantially in the opposite direction to the path of the organic material layer to achieve the desired water content of the organic material. A method of increasing the water content of a material. 4. The equilibrium CV of the organic material after step (c) is
14. The method of claim 13 wherein the equilibrium CV of the organic material prior to step (b) is not significantly less than. 5. The temperature of the organic material is less than about 38 ° C. (100 ° F.) before the organic material contacts the air stream.
The method according to any one of 4 to 4. 6. The method according to claim 1, wherein the organic material has an initial water content of about 1.5% to about 13% prior to the step of contacting the organic material with a stream of air. . 7. The method of claim 6, wherein the organic material has an initial water content of about 1.5% to about 6% prior to the step of contacting the organic material with the air stream. 8. The method of claim 3 wherein the desired water content of the organic material after step (c) is from about 11% to about 13%. 9. The air flow in contact with the organic material has a temperature of about 21 ° C.
9. The method of any one of claims 1-8 having a relative humidity of about 30% to about 64% at a temperature of (70 ° F) to about 49 ° C (120 ° F). 10. The temperature of the air stream is selected to perform the desired heat treatment on the organic material, while the relative humidity of the air stream is selected to readjust. The method described in one. 11. The organic material is tobacco, as claimed in any one of claims 1 to 1.
The method according to any one of 0. 12. The method of claim 11, wherein the tobacco is expanded tobacco. 13. The tobacco is selected from the group consisting of expanded or unexpanded tobacco, whole mesophyll tobacco, cut or chopped tobacco, mid-bone, reconstituted tobacco, or any combination thereof. The method according to claim 11. 14. A step of: (a) contacting an organic material with a stream having a relative humidity at or below the equilibrium of the organic material, and (b) achieving a desired water content of the organic material. Air contacting the organic material until the relative humidity of the air flow is maintained at a relative humidity close to or equal to the equilibrium state of the organic material, or the air contacting the organic material as the water content of the organic material decreases. Reducing the relative humidity of the stream, which comprises reducing the water content of the organic material. 15. Equilibrium CV of organic material after step (b)
15. The method of claim 14, wherein is not significantly lower than the equilibrium CV of the organic material prior to step (a). 16. (a) a step of forming a layer of an organic material by placing the organic material on a conveyor; (b) an air flow in which the organic material flows in a path substantially opposite to the path of the organic material layer. And (c) the moisture content of the organic material in such a manner that the relative humidity of the air stream contacting the organic material is maintained at or near the equilibrium relative humidity of the organic material or lower. A portion of the organic material is transferred to the air stream, and the organic material is gradually dehydrated as the air stream travels in a path approximately opposite to the path of the organic material until the desired water content of the organic material is achieved. And a method of reducing the water content of organic materials in which the air stream is gradually hydrated. 17. The method of claim 16, wherein the equilibrium CV of the organic material after step (c) is not significantly lower than the equilibrium CV of the organic material before step (b). 18. Further, the temperature of the organic material prior to step (a) is about 38 ° C. (100 ° F.) to about 121 ° C. (250 ° C.).
18. A method according to any one of claims 14 to 17, comprising the step of preheating to F). 19. The method of any one of claims 14-18, wherein the temperature of the organic material is below about 250 ° F. (121 ° C.) prior to the step of contacting the organic material with a stream of air. 20. The method of claim 19, wherein the temperature of the organic material is below about 100 ° F. (38 ° C.) prior to the step of contacting the organic material with the air stream. 21. The method of any one of claims 14-20, wherein the organic material has a water content of about 11% to about 40% prior to the step of contacting the organic material with a stream of air. 22. The air flow in contact with the organic material is about 21.
Approximately 2 at a temperature between 70 ° F (70 ° F) and 120 ° F (49 ° C)
22. The method of any one of claims 14-21 having a relative humidity of 0% to about 60%. 23. The method according to claim 14, wherein the temperature of the air stream is selected to carry out the desired heat treatment. 24. The method according to claim 14, wherein the temperature of the air stream is selected so as to be substantially free from heat treatment. 25. The temperature of the air stream is about 24 ° C. (75 °
F) to about 121 ° C (250 ° F).
4. The method according to any one of 4. 26. The method according to claim 14, wherein the organic material is tobacco.
25. The method according to any one of 25. 27. The method of claim 26, wherein the tobacco is cut tobacco. 28. The tobacco is selected from the group consisting of expanded or unexpanded tobacco, whole mesophyll tobacco, cut or chopped tobacco, mid-bones, reconstituted tobacco or any combination thereof. Item 27. The method according to any one of Items 26. 29. The step of contacting an organic material with a stream of air is carried out in a continuous manner using a spiral conveyor in which the stream of air flows in a path substantially opposite to the direction of flow of the organic material. The method described in any one of. 30. The step of contacting an organic material with an air stream is carried out in a continuous manner using a linear conveyor.
~ 29. The method according to any one of 29. 31. The linear conveyor is configured to provide multiple zones of increasing relative humidity.
The method described. 32. The step of contacting the organic material with a stream of air comprises about 0.23 m / sec (45 ft / min) to about 1.22 m.
32. A method according to any one of claims 1 to 31 carried out with an air flow having a velocity of / sec (240 ft / min). 33. The step of contacting an organic material with a stream of air passes the stream of air either downwards or upwards through the organic material layer or through the organic material layer both downwards and upwards. Claims 1-32 implemented by
The method described in any one of. 34. The method according to any one of claims 1 to 10 or 14 to 25, wherein the organic material is a hygroscopic organic material. 35. The method according to claim 29, wherein the hygroscopic organic material is fruits, vegetables, grains, coffee, pharmaceuticals, teas and combinations thereof. 36. The method according to claim 29, wherein the spiral conveyor comprises a stack having a plurality of layers, and the air stream flows in particular through successive layers in sequence and past the stack.