阅读说明：本技术 一种膨胀烟丝的高效制备方法 (Efficient preparation method of expanded cut tobacco ) 是由 黄贵文 肖红梅 渠成兵 刘玉 于 2018-06-26 设计创作，主要内容包括：本发明公开了一种膨胀烟丝的高效制备方法,该制备方法包括如下步骤：首先,烟丝原料吸水,得到湿胀的烟丝；然后,所述的湿胀烟丝和能溶于水的液体介质进行接触混合；再将接触混合后的烟丝进行干燥；最后将干燥后的烟丝回潮至所需含水量,得到膨胀烟丝。本发明方法的特点在于：利用液体介质与烟丝中的水接触形成混合溶液,改变其对烟丝的浸润性,可以消除或减小烟丝干燥过程中由水带来的干燥收缩应力,使烟丝膨胀体积得以保持。该过程条件温和,快速高效,利用该方法制备的膨胀烟丝膨胀率可调,效率高,可实现膨胀烟丝的连续化生产。(The invention discloses an efficient preparation method of expanded cut tobacco, which comprises the following steps: firstly, tobacco shred raw materials absorb water to obtain wet and expanded tobacco shreds; then, the wet swelling tobacco shreds are contacted and mixed with a liquid medium which can be dissolved in water; then drying the tobacco shreds after the contact mixing; and finally, dampening the dried cut tobacco to the required water content to obtain the expanded cut tobacco. The method of the invention is characterized in that: the liquid medium is contacted with water in the cut tobacco to form mixed solution, so that the wettability of the mixed solution on the cut tobacco is changed, the drying shrinkage stress caused by the water in the drying process of the cut tobacco can be eliminated or reduced, and the expansion volume of the cut tobacco is kept. The process has mild conditions, is rapid and efficient, the expansion rate of the expanded cut tobacco prepared by the method is adjustable, the efficiency is high, and the continuous production of the expanded cut tobacco can be realized.)

1. The efficient preparation method of the expanded cut tobacco is characterized by comprising the following steps of:

(1) absorbing water from the tobacco shred raw material to obtain wet and expanded tobacco shreds;

(2) the wet swelling tobacco shreds are contacted with a liquid medium, and the liquid medium can be dissolved in water;

(3) separating tobacco shred from liquid medium and water, and drying;

or

Directly drying;

(4) and (5) dampening the dried tobacco shreds to the required water content to obtain the expanded tobacco shreds.

2. The method for efficiently preparing expanded cut tobacco according to claim 1, wherein the liquid medium in the step (2) is one or more selected from polar compounds.

3. The method for efficiently preparing expanded cut tobacco according to claim 2, wherein the liquid medium in the step (2) is one or more selected from the group consisting of alcohols having 1 to 3 carbon atoms, acids having 1 to 4 carbon atoms, acetonitrile, acetone, acetaldehyde, propionaldehyde, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, ethylenediamine, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol dimethyl ether, diethylene glycol ethyl ether, 1, 3-dioxolane, and 1, 4-dioxane.

4. The method for efficiently preparing the expanded cut tobacco according to claim 3, wherein the alcohol with 1-3 carbon atoms is one or more selected from methanol, ethanol, 1-propanol, 2-propanol, ethylene glycol, 1, 2-propylene glycol and 1, 3-propylene glycol.

5. A high-efficiency preparation method of expanded cut tobacco according to claim 3, wherein the acid having 1 to 4 carbon atoms is one or two selected from acetic acid and propionic acid.

6. The efficient preparation method of the expanded cut tobacco according to any one of claims 1 to 5, wherein the moisture content of the wet expanded cut tobacco in the step (1) is 6-400%.

Technical Field

The invention relates to the technical field of tobacco shred production. And more particularly, to a method for efficiently preparing expanded cut tobacco.

Background

After the fresh tobacco leaves are harvested, conditioned, redried and stored, a large amount of water is lost inside the cells, resulting in a volume shrinkage of up to about 60%. A large amount of volume shrinkage can greatly reduce the filling capacity and the combustion performance of the cut tobacco, and can increase the generation amount of harmful substances such as tar in smoke and the unit consumption of the cut tobacco in cigarettes. In order to improve the defect and improve the cigarette quality, currently, in the cigarette production and manufacturing process, the tobacco shred expansion technology is mainly adopted to recover the initial volume of the tobacco shreds as much as possible, improve the filling capacity of the tobacco shreds and reduce the unit consumption of the tobacco shreds. The tobacco shred expansion technology has important economic benefits for cigarette manufacturers, and has important social benefits because the harm of tobacco to the health of consumers is reduced due to the reduction of the filling amount.

The conventional tobacco shred expansion methods are mainly classified into a freon expansion method, an alkane expansion method, a nitrogen expansion method, a carbon dioxide expansion method, and the like. Among them, the freon expansion method is forbidden due to the destructive effect on the ozone layer; in the alkane expansion method, an alkane expansion medium belongs to flammable and explosive substances with high risk grade, has high requirements on production environment and safety protection grade, and has the problem of extracting a large amount of tobacco shred components; although the expansion medium used in the nitrogen expansion method is environment-friendly and pollution-free, the expansion process can generate ultrahigh pressure of about 800 atmospheres, which is a great challenge to production equipment and operation safety; the carbon dioxide expansion method is a mainstream tobacco shred expansion method in China, but the carbon dioxide expansion method has the defects of large loss of carbon dioxide expansion technology, high equipment repair and maintenance cost, large tobacco shred fragrance loss, heavy scorched gas and high shred breaking rate, causes the problem of greenhouse gas pollution due to the emission of a large amount of carbon dioxide, does not accord with the direction of social low-carbon sustainable development, has the risks of limited use and the like, and all the defects force people to hope to carry out technical updating on the tobacco shred expansion method.

In order to solve a series of problems of high production cost and the like caused by using carbon dioxide as an expansion medium in the tobacco shred expansion process, water is used as a clean and environment-friendly expansion medium and is researched and applied to the tobacco shred expansion technology in recent years. For example, Chinese patent CN 1653968A discloses a process for expanding cut tobacco by using water as a medium. The method is characterized in that water is used as a medium and hot air is adopted for expansion in the tobacco shred expansion process, the physical property and the chemical property of the water determine that the tobacco shred is a substance of which the substance state is easy to change under the normal temperature and normal pressure states, the tobacco shred also easily absorbs the moisture to increase the water content inside and outside the cell, and the water has certain solubility on harmful substances in the tobacco shred, so that the water in the tobacco shred is quickly expanded and gasified under the action of high-temperature gas and is taken away by the high-temperature gas, and the tobacco shred can be expanded. For another example, an HXD expansion method is reported, in which after tobacco shreds absorb water, the tobacco shreds are heated in high-temperature circulating gas at a temperature of 200-400 ℃ to generate instantaneous high vapor pressure in tobacco shreds cells, so as to promote cell wall expansion and achieve tobacco shred expansion effect, and finally the tobacco shreds are dried and shaped to obtain the product. The production cost and equipment investment of the tobacco shred expansion technology are greatly reduced by taking water as an expansion medium, but the technical route still has many problems and defects:

(1) the tobacco shreds will become soft after absorbing water, and due to the structure with large length-diameter ratio, the tobacco shreds after absorbing water will be in a lumpy state, especially the tobacco shreds with high water content. The quality of the obtained expanded cut tobacco product can be influenced by directly carrying out subsequent processes on the lumpy cut tobacco;

(2) when the water-swelling cut tobacco is dried, certain drying shrinkage stress is brought to the cut tobacco by liquid water evaporation, so that the swelling volume of the cut tobacco is difficult to maintain;

(3) the high temperature condition causes obvious loss of the aroma and the flavor of the cut tobacco and obviously causes crumbling in the airflow drying process;

(4) the expansion effect is greatly reduced due to side effects caused by crushing, and the finally obtained expanded cut tobacco has low filling capacity and can only be used as a low-grade raw material of cigarettes.

Therefore, in order to solve the problems in the technical route, the invention provides a tobacco shred expansion method by using environment-friendly medium water as an expansion medium, and innovatively provides a technical scheme for eliminating or reducing drying shrinkage stress by using the contact of a liquid medium and tobacco shreds. The technical scheme provided by the invention greatly improves the production efficiency of the expanded cut tobacco by taking water as an expansion medium, can realize the rapid and continuous production of the expanded cut tobacco and has good economic and social benefits.

Disclosure of Invention

The invention aims to provide an efficient preparation method of expanded cut tobacco, which takes environment-friendly medium water as an expansion medium, greatly improves the production efficiency of the expanded cut tobacco on the premise of ensuring and even improving the expansion effect, avoids the influence of high temperature and strong air flow on the cut tobacco, and realizes high-quality, rapid and continuous production of the expanded cut tobacco.

The basic principle of the invention is as follows: firstly, tobacco shred raw materials absorb water to obtain volume expansion; then, the tobacco shreds absorbing water contact with a liquid medium capable of dissolving in water, and then are separated and dried through a mixed solution or directly dried after the tobacco shreds contact with the liquid medium, and finally, the expanded tobacco shreds are obtained through a moisture regaining process. The method is characterized in that: since the liquid medium is soluble in water, when the aqueous tobacco shreds are contacted with the liquid medium, the water in the tobacco shreds cells will quickly diffuse into the liquid medium, forming a mixed solution of water and the liquid medium. After the mixed solution is formed, the wetting property of the mixed solution on the cut tobacco is changed, so that the drying shrinkage stress of the cut tobacco caused by water can be eliminated or weakened. The tobacco thread is able to maintain its expanded form during this contact and, due to the elimination or reduction of drying shrinkage stresses, is able to substantially maintain its expanded form during subsequent drying. Compared with the high-temperature airflow method, the method has the advantages that the conditions in the tobacco shred processing process are mild, the operation is rapid and efficient, the liquid medium can be repeatedly recycled after dehydration treatment, the production efficiency of the expanded tobacco shred is greatly improved, the production energy consumption is greatly reduced, and the expanded tobacco shred can be efficiently and continuously produced.

According to the principle, the invention realizes the purpose of the invention by implementing the following technical scheme. An efficient preparation method of expanded cut tobacco is characterized by comprising the following process steps:

(1) absorbing water from the tobacco shred raw material to obtain wet and expanded tobacco shreds;

(2) the wet swelling tobacco shreds are contacted with a liquid medium, and the liquid medium can be dissolved in water;

(3) separating tobacco shred from liquid medium and water, and drying;

or

Directly drying;

(4) and (5) dampening the dried tobacco shreds to the required water content to obtain the expanded tobacco shreds.

The tobacco shred raw material in the process step (1) of the invention is the tobacco shred before expansion treatment. The process of absorbing water from the tobacco shred raw material is the process of increasing the water content of the tobacco shred, the conditions of the process are not limited, if the tobacco shred can be directly placed in water or sprayed with water at normal temperature and normal pressure to freely absorb water and swell, or the tobacco shred can be soaked in water or sprayed with water to expand at a certain temperature or under a certain pressure. In addition, the water content of the wet and expanded tobacco shreds is controlled and regulated by controlling the time of contact between the tobacco shreds and water or the water addition amount. The moisture content of the wet and expanded cut tobacco can reach the saturated water absorption capacity of the cut tobacco, and the moisture content of the wet and expanded cut tobacco is controlled to be 6-400%. Further, the moisture content of the swollen cut tobacco includes, but is not limited to, for example, 50% -400%, 100% -350%, 120% -300%, 150% -250%, 50% -100%, 20% -50%, and the like.

The selection of the liquid medium involved in step (2) of the method of the present invention is not limited except for the special requirement of "water-soluble", i.e., the liquid compound that is soluble in water is within the scope of the present invention. The term "soluble in water" as used herein means having a certain solubility in water. Depending on the solubility difference in water, including but not limited to, readily soluble, slightly soluble, and the like. If one liquid medium is selected, the liquid medium and the water are preferably in a mutual soluble state, and the mutual solubility generally refers to a phenomenon that two substances are mixed, including a partially mutual soluble state; if two or more liquid media are selected, the liquid media and the water are preferably in a miscible state, and the miscible state generally refers to a phenomenon that three or more substances are mixed together and fused with each other.

Two cases are involved in step (3) of the process of the invention. Generally, when the cut tobacco in the step (2) has a large water content or a large amount of liquid medium is added, a mixed solution of the liquid medium and water exists outside the processed cut tobacco, and at this time, the cut tobacco is preferably separated from the mixed solution and then dried; and (3) under the condition that the water content of the cut tobacco in the step (2) is low or the adding amount of the liquid medium is low, and the treated cut tobacco does not have or only has a small amount of mixed solution, the mixed solution can be directly dried without separation. Of course, the above-mentioned methods can be interchanged without considering the cost and time, and the final effect is not influenced by the method and the step of removing the liquid medium and the water.

According to the basic principle of the method according to the invention, it will be understood by a person skilled in the art that the contacting process according to the invention is essentially a process of mixing the water in the swollen cut tobacco with the liquid medium, i.e. a process of mixing at least part of the water in the swollen cut tobacco with the liquid medium. The solution according to the invention can be successfully implemented by the liquid medium only having to satisfy the "water-soluble" requirement, which is predictable to the person skilled in the art, and it is therefore not necessary here to list all liquid media that are soluble in water to prove the feasibility of this solution.

Further, the liquid medium according to the present invention is preferably selected from one or more of polar compounds. Polar compounds are molecules known to those skilled in the art with dipole moments μ ≠ 0, i.e. molecules in which the centers of positive and negative charges do not coincide, the distribution of charges is not uniform throughout the molecule, asymmetric molecules, and such compounds are generally readily soluble in water.

The liquid medium involved in the method of the present invention may be one or more selected from alcohols with 1 to 3 carbon atoms, acids with 1 to 4 carbon atoms, acetonitrile, acetone, acetaldehyde, propionaldehyde, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, ethylenediamine, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol dimethyl ether, diethylene glycol diethyl ether, 1, 3-dioxolane, and 1, 4-dioxane.

Preferably, the alcohol with 1-3 carbon atoms is selected from one or more of methanol, ethanol, 1-propanol, 2-propanol, ethylene glycol, 1, 2-propylene glycol and 1, 3-propylene glycol.

Preferably, the acid of 1 to 4 carbon atoms is selected from one or both of acetic acid or propionic acid.

The operation mode of contacting the wet expanded tobacco shreds with the liquid medium in the step (2) of the method comprises the steps of dispersing the tobacco shreds into the liquid medium, spraying the liquid medium onto the tobacco shreds, and adding the liquid medium or other means capable of contacting the tobacco shreds with the liquid medium in the process of stirring and stirring the tobacco shreds by turning over, namely, all means capable of contacting the tobacco shreds with the liquid medium are within the protection range of the invention, and preferably, the tobacco shreds are uniformly contacted with the liquid medium.

The drying mode in step (3) of the method of the present invention may be normal pressure drying, vacuum drying or other drying means capable of sufficiently drying water or a liquid medium or a mixture of both. In the drying process, a liquid medium which can form an azeotrope with water evaporates in the form of the azeotrope with water according to an azeotropic ratio, and the part outside the ratio evaporates separately; the liquid medium which does not form an azeotrope with water evaporates separately from water.

In addition, the moisture content of the tobacco shreds after being dried in the step (4) of the method can be determined according to actual conditions, and the moisture content of the expanded tobacco shreds is generally 12-13%.

The invention has the following beneficial effects:

compared with the prior art, the high-efficiency preparation method of the expanded cut tobacco provided by the invention has the following advantages:

1) the production process is clean and environment-friendly, and no pollutant is discharged;

2) the production condition is mild, special equipment such as high temperature, ultrahigh pressure and the like is not needed, and the method is easy to implement;

3) the expansion rate of the tobacco shreds is adjustable, and the expanded tobacco shreds are regular in shape and easy to roll;

4) the tobacco shred production efficiency is high, and continuous production can be realized;

5) the shredded tobacco has low breakage rate, reduces the waste of the shredded tobacco and has high filling capacity.

Drawings

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

FIG. 1 is a schematic flow diagram of the preparation process of the present invention.

Fig. 2 shows the state of the swollen tobacco shreds before (a) and after (b) contact with the medium, respectively.

Detailed Description

In order to more clearly illustrate the invention, the invention is further described below with reference to preferred embodiments and the accompanying drawings. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.

The technical solution of the present invention is described below with reference to some preferred embodiments: