CN201219480Y - Pulse airflow drying equipment for tobacco material - Google Patents

Abstract

A pulse airflow drying device for tobacco materials, characterized in that it includes an air inlet (1) and a feed valve (2) at one end, and the other end is connected to the upper part of the inner cavity of a drying tower (7) with an inverted conical structure The material conveying drying pipe through which the material conveying and drying pipe comprises a feed pipe (4), a discharge pipe (6) and a vertically arranged lumen between the feed pipes is an expansion chamber of a Venturi structure (5) Three parts; wherein, the expansion cavity is an inverted tapered cavity that gradually converges from the feed end to the discharge end; the discharge pipe (6) connected to the discharge end at the bottom of the expansion cavity is formed by The way of bending upwards is connected with the feeding port arranged on the upper part of the drying tower (7); The feed end is respectively connected with the gas source and the material source through the air inlet (1) and the feed valve (2).

Description

Tobacco material pulse air drying equipment

technical field

The utility model belongs to the technical field of tobacco processing, and in particular relates to a pulsed airflow drying equipment for tobacco materials which uses pulsed airflow to expand and dry tobacco materials.

Background technique

At present, the cut stem puffing drying modes commonly used in the domestic tobacco processing industry mainly include: 1. HT plus drying cut stem cylinder; 2. COMAS cut stem puffing tower; 3. Flash grafting cut stem puffing tower; 4. Flash plus flow Bed; 5, HT plus fluidized bed; 6, COMAS tunnel-type shredded stem drying machine and other modes. The common disadvantage of these modes is that the moisture balance of cut stems at the outlet section of the equipment is poor. At the same time, the moisture balance index limits the cross-section of the material from being expanded arbitrarily, which in turn limits the improvement of production capacity. The maximum production capacity of the current cut stem puffing and drying modes can only reach 2000Kg/h, so the popularization and application in domestic large-scale tobacco factories has great limitations.

Patent 200620128143.1 discloses an airflow stem cut drying tower, which is basically a simplified form of a flash grafted cut stem puffing tower. Because airflow drying is particularly sensitive to feed, cut stems enter the drying tower directly through a venturi tube, and it is difficult to achieve a flow rate for feed Balanced, and its drying route is short, it is difficult to achieve effective drying of materials and uniform discharge moisture.

Patent 03221595.9 discloses a fluidized dryer for drying cut stems. By modifying the interior of the traditional fluidized bed, the balance of moisture at the outlet of the cut stems is improved. The thickness of the material layer is limited by the characteristics of airflow drying, so it is difficult to achieve drying of cut stems with large flow.

Contents of the invention

The purpose of the technical solution of the utility model is to provide a pulsed airflow drying equipment for tobacco materials by overcoming the above-mentioned shortcomings in the prior art.

The equipment of the utility model introduces the pulse airflow drying technology in the puffing and drying process of the tobacco material. On the basis of the flash puffing, the pulse airflow drying technology is used to continuously add the material into the drying pipe. The moisture of the material is evaporated to realize the puffing and drying of the large-flow tobacco material, and at the same time, it can further improve the moisture uniformity of the exported material, and finally obtain the dried material.

The purpose of this utility model can be achieved through the following technical measures:

The pulse airflow drying equipment for tobacco materials of the present invention comprises a material delivery drying pipe which is provided with an air inlet and a feed valve at one end and communicates with the upper part of the inner cavity of the drying tower with an inverted conical structure at the other end. The material delivery drying pipe Including the feed pipe, the discharge pipe and the vertically arranged lumen between the feed and discharge pipes are three parts of the expansion chamber of the Venturi structure; wherein, the expansion chamber is gradually formed from the feed end to the discharge end. Convergent inverted conical cavity; the discharge pipe connected to the discharge end at the bottom of the expansion chamber is connected to the feed port on the upper part of the drying tower in a way of bending from bottom to top; the feed pipe connected to the upper part of the expansion chamber The end-to-end feed pipe is bent from top to bottom, and its feed end is connected to the gas source and the material source respectively through the air inlet and the feed valve.

The top of the drying tower in the utility model is provided with a transfer screen and an air outlet, and the bottom is provided with a discharge air lock and a discharge port.

The working principle of the utility model equipment is as follows:

The utility model makes the diameter of the conveying drying pipe into a form of alternate expansion and contraction (that is, the conveying and drying pipe adopting the Venturi structure), so that the tobacco material is continuously accelerated and accelerated during the conveying process of the drying pipe. Slow down, when the gas-solid mixture flows at high speed in the drying pipe, the moisture of the material evaporates rapidly, and the material is puffed and dried. Its specific process steps are as follows:

(1) The flash-expanded tobacco material enters the feed valve from the feed port through the vibrating tank, and then falls into the feed pipe with a relatively small diameter;

(2) The high-speed airflow is blown into the feeding pipe from the air inlet to accelerate the material;

(3) When the accelerated material enters the expansion chamber at the moment, due to the sudden expansion of the pipe diameter, the airflow speed drops suddenly, and the material enters the expansion chamber due to inertia;

(4) The tobacco material is continuously decelerated under the action of the variable diameter resistance of the inverted conical cavity, until the relative velocity between the gas-solid two phases is equal to or close to the material sedimentation velocity, and the material is accelerated again due to the sudden reduction of the pipe diameter ;

(5) So repeated, the material is always in the state of being accelerated or decelerated, which strengthens the heat and mass transfer process, improves the drying capacity of the equipment and enhances the puffing effect of the material, and also shortens the length of the drying tube;

(6) The hot air flow is discharged from the air outlet through the transfer net in the drying tower, a part of the moisture is discharged into the atmosphere, and most of the hot air flow returns to the hot blast stove or other heating devices to re-enter the air inlet after heating;

(7) The dried tobacco material is output from the discharge port through the discharge air lock.

The beneficial effects of the utility model are as follows:

Compared with the existing technology, it can not only strengthen the heat and mass transfer process, but also has the characteristics of high drying efficiency, small footprint, large production capacity per unit volume, easy automatic control, etc., and the contact area is greatly increased because the pulse air flow moves with the material , so that the material is heated more evenly, so the drying process is strengthened, not only the heat and mass transfer efficiency is high, the energy consumption is small, but also the product processing quality is more uniform.

In addition, pulsed airflow drying of tobacco materials also has the following beneficial effects:

1. It is beneficial to eliminate woody gas, green miscellaneous gas and other miscellaneous gases of tobacco materials;

2. The tobacco material moves at high speed in the drying tube, which has a certain puffing effect. After multiple pulses, the puffing effect is further enhanced;

3. Tobacco materials are dried in a closed environment, not easy to oxidize and brown, and the materials are soft and curly, with good compatibility;

4. The hot air circulation is used to save energy.

The tobacco material described in the utility model includes shredded tobacco, shredded leaves, shredded stems, tobacco sheets and the like.

Description of drawings

Fig. 1 is the structural representation of the utility model equipment.

Serial numbers in Figure 1: 1, air inlet, 2, feed valve, 3, feed inlet, 4, feed pipe, 5, expansion chamber, 6, discharge pipe, 7, drying tower, 8, transfer net, 9. Air outlet, 10. Discharge air lock, 11. Discharge port.

Detailed ways

The utility model will be further described below in conjunction with embodiment (accompanying drawing):

The pulse airflow drying equipment for tobacco materials of the present utility model comprises an air inlet 1 and a feed valve 2 at one end, and a material delivery drying pipe connected to the upper part of the inner chamber of the drying tower 7 with an inverted conical structure at the other end. The material drying pipe comprises three parts: feed pipe 4, discharge pipe 6 and the vertically arranged lumen between the feed pipe and the expansion chamber 5 of Venturi structure; wherein, the expansion chamber is formed by the feed The inverted tapered cavity gradually converges from the end to the discharge end; the discharge pipe 6 connected to the discharge end at the bottom of the expansion chamber is connected to the feed port set on the upper part of the drying tower 7 in a way of bending from bottom to top ; The feed pipe 4 connected to the feed end of the upper part of the expansion chamber is arranged in a manner of bending from top to bottom, and the feed end of the feed pipe 4 is connected to the gas source through the air inlet 1 and passed through the feed valve 2 The feed port 3 is connected to the material source; the top of the drying tower 7 is provided with a transfer screen 8 and an air outlet 9, and its bottom is provided with a discharge air lock 10 and a discharge port 11.

In the utility model, the puffing pretreatment of the tobacco material can be completed by flash evaporation or other puffing equipment; the moisture in the entrance of the tobacco material is controlled at 18%-38%, and the feeding drying pipe is controlled by the feed valve 2 to be isolated from the air; the air velocity is at Between 4m/s-40m/s, the preferred speed is 5m/s-25m/s. The outlet moisture of the tobacco material is 8%-13%, and the feeding drying pipe is isolated from the air by the discharge valve 10. The drying time of the tobacco material in the drying pipe is 0.5-20s, and the preferred time is 5-15s. The temperature of the hot air in the drying pipe is 100°C-250°C, preferably 120°C-220°C.

In the actual production process, the equipment can be used to achieve multiple pulse drying, generally 1-5 pulse drying, preferably 2-3 pulse drying.

Claims (2)

1, a kind of tobacco pulsed pneumatic drying equipment, it is characterized in that: it comprises that an end is provided with the defeated material drying tube that air inlet (1) and inlet valve (2), the other end are connected with the inner chamber top of the drying tower (7) of inverted cone-shaped structure, and described defeated material drying tube comprises that the tube chamber of feed pipe (4), discharge nozzle (6) and the vertical setting between feed and exhaust tube is Venturi tube-type spreader expansion of structure chamber (5) three parts; Wherein, the back taper cavity of described expansion chamber for restraining gradually to discharge end by feed end; The discharge nozzle (6) that is connected with the discharge end of expansion chamber bottom is connected with the charging aperture that is arranged on drying tower (7) top in the mode of bending from bottom to top; The feed pipe (4) that is connected with the feed end on expansion chamber top is provided with in the mode of bending from top to bottom, and its feed end links to each other with the material source with source of the gas respectively with inlet valve (2) by air inlet (1).

2, tobacco pulsed pneumatic drying equipment according to claim 1 is characterized in that: the top of described drying tower (7) is provided with changes net (8) and gas outlet (9), and its bottom is provided with discharging gas lock (10) and discharging opening (11).

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