Tobacco shred feeding treatment device and method for improving heat energy and feed liquid absorption efficiency of tobacco shred

The invention relates to a tobacco shred feeding treatment device and a method for improving the heat energy and feed liquid absorption efficiency of tobacco shred, comprising: a tobacco shred feeding machine, said tobacco shred feeding machine mainly comprises a roller, a process warm-air pipe, a power blower, a heater, a steam nozzle, a feed liquid nozzle and an air inlet pipe; the process warm-air is blown into said roller from said air inlet pipe via said steam nozzle and said heater under the action of said power blower, and mixed with the tobacco shred; said air inlet pipe is provided directly under the central axis of said roller; the opening of said air inlet pipe faces up obliquely, and the opening direction of which could be adjusted into any position within the roller according to the requirements; said steam nozzle is mounted between the power blower and the heater, to achieve heating the condensed water in the steam, and to avoid directly injecting the steam to burn the tobacco shred. Under the premise that it is not necessary to configure the tunnel heating and humidifying equipment, the process warm-air with steam can contact with the tobacco shred sufficiently to improve the heat energy and feed liquid absorption efficiency and uniformity.

CROSS-REFERENCE TO RELATED APPLICATION

This is a US Non-Provisional Application which claims priority to Chinese Patent Application No. 201310357315.7 filed on Aug. 16, 2013, the entirety of which is incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to the field of tobacco electrical automatic control, particularly to a tobacco shred feeding treatment device and a method for improving the heat energy and feed liquid absorption efficiency of tobacco shred.

BACKGROUND OF THE INVENTION

At present, during the manufacturing of tobacco shred making, there are two kinds of feeding treatment processes: tobacco flake feeding treatment process and tobacco shred feeding treatment process. The traditional shred making production lines all use tobacco flake feeding treatment process. In recent years, the tobacco shred feeding treatment process is increasingly applied in the cigarette production lines.FIG. 1shows the structure schematic drawing of the existing tobacco shred feeding treatment device. As shown inFIG. 1, the tobacco shred feeding treatment device includes a tobacco shred feeding machine, a vibration groove1′ and a tunnel heating and humidifying equipment2′, the vibration groove1′ and the tunnel heating and humidifying equipment2′ are provided orderly in the feeding end of tobacco shred feeding machine (the right side of tobacco shred feeding machine shown inFIG. 1). After being heated and humidified by the tunnel heating and humidifying equipment2′, the tobacco shred is conveyed to the tobacco shred feeding machine via the vibration groove1′ to get the feeding treatment.

The tobacco shred feeding machine includes a roller3′, a process warm-air pipe4′, a power blower5′, a heater6′, a steam nozzle7′, a feed liquid nozzle8′ and an air inlet9′. The process warm-air A′ is blown by the power blower5′, via the hot blast heater6′ from the position above the central axis of the roller3′, and flows into the roller3′ in the same direction as the tobacco shred conveyed from the vibration groove1′, and mixed with the tobacco shred. At the same time, the tunnel heating and humidifying equipment2′ implements the heating and humidifying of tobacco shred, and the suitable temperature and humidity is advantageous to improve the feed liquid absorption rate of tobacco shred. The arrow direction B′ depicted inFIG. 1indicates the direction of the process warm-air A′ with steam, the arrow direction C′ indicates the moisture removal direction in the system, and the arrow direction D′ indicates the tobacco shred conveying direction.

The method of processing tobacco shred by the prior tobacco shred feeding treatment device has the following disadvantages:

1. The process warm-air A′ is blown into the roller3′ at positions above the central axis of the roller3′, only contacts with the tobacco shred falling down from above, has a small contact area with tobacco shred, cannot make sufficient heat exchange with the inner tobacco shred, which lead to the temperature and the moisture content of the tobacco shred cannot meet the process requirements. In order to ensure that the tobacco shred meet the process requirements of the temperature and the moisture content, it is necessary to increase the steam pressure to increase the steam injection amount and the speed of the process warm-air, so that the process warm-air with steam and feed liquid in the roller3′ is directly blown to the end of the roller3′ in the case of having not contacted with the tobacco shred and being absorbed sufficiently, and most of them are removed by the moisture removing blower10′, easily to cause the phenomenon of tobacco shred moisture content and feed liquid absorption uneven and cause the waste of feed liquid and energy. At the same time, some of the feed liquid adhere onto the mesh belt of the moisture removing port C′, as time goes by, the feed liquid adhering onto the mesh belt will drop into the tobacco shred at the discharging port, easily to cause the appearance of macular tobacco.

2. The condensed water will be produced when the process warm-air A′ with steam come into contact with the low temperature process warm-air pipe, the condensed water goes into the feeding machine along with the process warm-air A′, and mixes directly with the tobacco shred, causing wet mass and water staining tobacco, which is disadvantageous for the manufacture of subsequent workstage and affects the quality of tobacco shred.

3. The tunnel heating and humidifying equipment2′ need to be configured in the front end, and the equipment is easily to cause uneven tobacco shred moisture content, and the tobacco shred wet mass and scaling is easily to produce, which lead to the sensory quality reduction of tobacco shred. At the same time, the tunnel heating and humidifying equipment2′ is a tobacco shred equipment having high energy consumption and serious environmental pollution problem, with high workload of daily cleaning and maintenance.

4. The steam nozzle7′ is provided in the feeding end of the roller3′, with the condensed water in the steam directly spraying onto the tobacco shred, causing tobacco shred wet mass and water staining tobacco. Internationally, there are some devices related to steam absorption efficiency of tobacco flake or tobacco shred, which adopt the way of steam nozzle directly injecting to the feed, easily to cause tobacco leaves or tobacco shred burnt, and more easily to cause obvious falling sensory quality reduction particularly for higher quality of flue-cured tobacco.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, with reference to the accompany drawings and embodiments, the technical solution of the invention will be further described in detail.

As shown inFIG. 2, the tobacco shred feeding treatment device provided by the present invention for improving the heat energy and feed liquid absorption efficiency of tobacco shred includes a tobacco shred feeding machine and a vibration groove, the feeding end of the tobacco shred feeding machine (the right end of the tobacco shred feeding machine as shown inFIG. 2) does not need to configure the tunnel heating and humidifying equipment. Since the tunnel heating and humidifying equipment is easily to cause uneven tobacco shred moisture content, and the tobacco shred wet mass and scaling is easily to produce, which lead to the sensory quality reduction; meanwhile, the tunnel heating and humidifying equipment is a tobacco shred equipment having high energy consumption and serious environmental pollution problem, with high workload of daily cleaning and maintenance, so the present invention not only ensures the sensory quality stability of the tobacco shred, but also reduces the energy consumption and environmental pollution, and cuts down the device investment and the cost of daily operation and maintenance.

What's same with prior art is that: the tobacco shred feeding machine mainly comprises a roller3, a process warm-air pipe4, a power blower5, a steam nozzle6, a heater7, a feed liquid nozzle8and an air inlet pipe11. The process warm-air A is blown by the power blower5, via the heater7, from the air inlet pipe11into the roller3, and mixed with the tobacco shred.

What's different from prior art is that: the air inlet pipe11is provided directly under the central axis of the roller3, the opening of the air inlet pipe11faces up obliquely. As can be seen fromFIG. 2, the opening of the air inlet pipe11is tilting upward, the process warm-air with the steam sprayed from the air inlet pipe11is spraying upward obliquely from the lower part, and sufficiently contacts with the largely loosened tobacco shred falling from the height, solved the following disadvantages in the prior art: the process warm-air A is blown into the positions above the central axis of the roller3′ by a fixed air inlet pipe in the prior art, only contacts with the tobacco shred falling down from above, has a small contact area with tobacco shred, and cannot make sufficient heat exchange with the inner tobacco shred. The blowing mode from upper to lower in the present invention will increase the contact area with tobacco shred significantly, thus making the heat energy absorption of tobacco shred more sufficient and more uniform.

On the basis of the structure of prior tobacco shred feeding treatment device, the tunnel heating and humidifying equipment2′ is omitted in the present invention, the original fixed air inlet pipe is changed into an angle-adjustable air inlet pipe, depending on the difference of the feed flow and the speed of the roller, by adjusting the suitable angle of air inlet pipe11, the process warm-air A is ensured to contact with tobacco shred sufficiently, and the heat exchange and the feed liquid absorption are made uniformly, reducing the phenomenon of tobacco shred adhering onto the roller significantly, and reducing the waste of feed liquid and energy. The process warm-air speed within the roller3is adjusted to be 1.0 to 2.0 times of the travelling speed of tobacco shred in the roller3by adjusting the frequency of the power blower5, further ensuring the time of the heat energy and feed liquid absorption of tobacco shred, reducing the wastage of process warm-air A with feed liquid due to being discharged by the moisture removing system.

A universal joint10is also provided, and it can be achieved that the opening of the air inlet pipe11may adjust its opening direction into any position within the roller according the requirements, with the universal joint as its center. The air inlet pipe11is in communication with the air outlet of the process warm-air pipe4via the universal joint10. In this embodiment, the universal joint10is made of a food grade soft material having high temperature resistance, moisture resistance and good toughness, which can be directly available from the market.

In the above mentioned embodiment, as shown inFIG. 2, the air inlet pipe11may be either a square pipe, or a circular or oval pipe. However, whatever the shape of the air pipe is, in order to make sure that not only the air flow can go into the roller3via the air inlet pipe11, but also the tobacco shred11falling from the upper portion of roller3will not fall into the opening of the air inlet pipe11, the opening end surface of the air inlet pipe11is provided as tilting surface, and the upper wall of the air inlet pipe11is longer than its lower wall.

In the above-mentioned embodiment, the process warm-air pipe4is tilting upward in the upper portion of the roller3in relation to the direction of process warm-air, the steam nozzle6is installed between the power blower5and the heater7, and at the same time injects the steam perpendicular to the process warm-air pipe4, so that the condensed water carried in the steam can be discharged from the lowest point of the process warm-air pipe4, avoiding to go into the heater7that cause the heater7bear heat-expansion and cold-contraction frequently to affect its service life; avoiding the high temperature steam to have an impact on the performance of power blower5; solving the tobacco shred's burn caused by the high temperature steam injecting directly onto the tobacco shred to increase the temperature, especially avoiding the sensory quality reduction for higher quality of flue-cured tobacco; the injecting steam and the process warm-air are sufficiently mixed before go into the roller3, with the uniformity of tobacco shred heat absorption improved.

In the above mentioned embodiments, the present invention may also include the condensed water collecting pipe9, and the condensed water collecting pipe9is in communication with the air outlet of the process warm-air pipe4, and the opening of the condensed water collecting pipe9faces downward, by providing the condensed water collecting pipe in the air outlet of the process warm-air pipe4, the condensed water is completely prevented to go into the roller3with the process warm-air, the production of tobacco shred wet mass of and water staining tobacco is reduced, and the tobacco shred feeding effectiveness and the quality stability are improved.

In the above mentioned embodiments, the bottom surface of the condensed water collecting pipe9is provided with a device such as a spring sheet which airflow cannot go through but a preset amount of condensed water can go through due to gravity (not shown in the drawings), the area of the spring sheet is enough to completely cover the bottom opening of the condensed water collecting pipe9, and one end of the spring sheet is fixedly connected to the bottom of the condensed water collecting pipe9, while the other end is in suspension. Therefore, when the weight of condensed water on the spring sheet is not enough to push the spring sheet away, the suspension end of the spring sheet is affixed to the bottom surface of the condensed water collecting pipe9, making the airflow cannot to go through.

In the above embodiments, the invention also comprises a temperature detection mechanism2, the temperature detection portion of said temperature detection mechanism2is located inside the return air portion of said process warm-air pipe4; the temperature display portion of said temperature detection mechanism2is located outside of said process warm-air pipe4, and the temperature of the return air portion in said process warm-air pipe4can be detected with said temperature detection mechanism2. By slightly adjusting the frequency of the power blower5and the steam injection amount of the steam nozzle6, the difference value between the temperature of the return air part in the process warm-air pipe and the tobacco shred temperature at the discharging port12of the roller is within 1° C., and the temperature of the tobacco at the exit of the roller is ensured to meet the process requirements. Therefore, the effectiveness and uniformity of heat energy and the feed liquid absorption of tobacco shred are further ensured;

The invention also provides a tobacco shred feeding treatment method using the tobacco shred feeding treatment device mentioned in the above embodiments, including the following steps:

1) Parameter design. When the controlling belt weigher13in the front section workstage of the feeding machine sends out the feed presence signal, starting the steam nozzle (6) of tobacco shred feeding machine after a period of time to inject steam into the process warm-air (A) for heating the tobacco shred; opening the feeding nozzle (8) after another period of time to feed the heated tobacco shred;

2) Starting the production line, preheating the equipment, and making the physical tests after the completion of preheating;

3) Observing the throwing trajectory and throwed state of the tobacco shred after being delivered into the tobacco shred feeding machine under the action of rake nail, and in the case of continuous production, finding out an area which is most loose and in which the feed layer throwing surface is the largest during the tobacco shred throwing course at the feeding end in the roller3;

4) Adjusting the orientation of the air inlet pipe11, turning the opening direction of the air inlet pipe11directly opposite to the area which is most loose and in which the feed layer throwing surface is the largest during the tobacco shred throwing course selected from step 3);

5) Adjusting the steam injection amount of the steam nozzle6applied to the process warm-air pipe4, and adjusting the temperature of the tobacco shred after being treated by the roller3, such that the process requirements is fulfilled;

6) Adjusting the frequency of the power blower5, such that the process warm-air speed within the roller3is adjusted to be 1.0 to 2.0 times of the travelling speed of tobacco shred in the roller3(the air speed in the roller2is generally designed to be 8-10 times of the flow rate of tobacco shred in the device manufactory), preferably making the steam inside the roller3just not to overflow;

7) Slightly adjusting the frequency of the process warm-air power blower5and the steam injection amount of steam nozzle6:

Detecting the tobacco shred temperature in the discharging port12of the roller3, and comparing it with the temperature detected by the temperature detection mechanism2. When the temperature difference between them is greater than 1° C., reducing the frequency of the power blower5gradually, until the temperature difference between them is within 1° C.

Compare the temperature collected by the temperature detection mechanism2with the set value of the process requirements. When the collected temperature is higher than the process requirements, the steam injection amount of the steam nozzle6will be gradually reduced; when the collected temperature is lower than the process requirements, the steam injection amount of the steam nozzle6will be gradually increased, until the collected temperature conforms to the process requirements.

In the above method, the method of the present invention may also include the step of slightly adjusting the frequency of the power blower5and the steam injection amount of the steam nozzle6, at the same time comparing the tobacco shred temperature in the discharging port12of the roller3with the temperature detected by the temperature detection mechanism2, until the temperature difference between them being within 1° C. Therefore, the heat energy and feed liquid absorption efficiency and uniformity of tobacco shred is further ensured.

In the above method, the method of the present invention may also include the step of collecting condensed water generated in the process warm-air pipe4with the condensed water collecting pipe9. The original fixed air inlet is changed into an angle-adjustable air inlet in the method of the present invention, at the same time, the condensed water collecting pipe9is provided in the air outlet of the process warm-air pipe4, and the condensed water is completely prevented to go into the feeding roller3with the process warm-air.

Now the invention will be described in an example of a tobacco shred feeding machine of 3000 kg/h, in combination with the accompany drawings and the embodiments.

1) Parameter Design

The speed of the roller3is set to 10 RPM;

The rotation direction of the roller: in clockwise direction as seen from the feed direction;

The pressure of the steam nozzle6is set to 1.6 bar;

The frequency of the power blower5is set to 6 Hz;

The frequency of the moisture removing blower1is set to 6 Hz;

The process return air temperature2is set to 50° C.;

The pilot injection pressure of the feeding nozzle8is set to 0.8 bar.

Settings of the preheating mode: starting the roller3, the heater7, the power blower5simultaneously, turning off the moisture removing blower1, the preheating will be completed when the process warm-air is preheated to 70° C. (collected by the temperature detection mechanism2), and waiting for the feed.

Settings of the production mode: When the controlling belt weigher13in the front section workstage of the feeding machine sends out the feed presence signal, starting the steam nozzle6of tobacco shred feeding machine after a delay of 25 seconds to inject steam into the process warm-air A, and heating the tobacco shred going into the roller3, opening the feeding nozzle8after another delay of 15 seconds to feed the heated tobacco shred, at the same time starting, the moisture removing blower1, then the normal production starts.

2) Starting the production line, making physical test according to the process parameters set in step 1).

3) Observing the throwing trajectory and throwed state of the tobacco shred after being delivered into the tobacco shred feeding machine under the action of rake nail, and finding out an area which is most loose and in which the feed layer throwing surface is the largest during the tobacco shred throwing course at the feeding end in the roller3.

4) Adjusting the orientation of the air inlet pipe11, turning the opening direction of the air inlet pipe11directly opposite to the area which is most loose and in which the feed layer throwing surface is the largest during the tobacco shred throwing course selected from step 3). At this time the air inlet pipe11is inclined upward at an elevation angle of 45°, as shown inFIG. 3, turning left 75° as seen from the feed flow direction.

5) Slightly adjusting the steam injection amount of steam nozzle4and the frequency of the power blower3:

The temperature collected by the temperature detection mechanism2is automatically compared with the return air temperature in the process requirements (the set value is 50° C.), the automatic control system14automatically adjusts the steam injection amount of the steam nozzle6.

Detecting the tobacco shred temperature in the discharging port12of the roller3, and comparing it with the temperature detected by the temperature detection mechanism2in the return air portion of the process warm-air pipe4, the temperature difference between them is merely 0.6° C., and conform to the requirements of the above method. Therefore, it is not necessary to adjust the frequency of the power blower5.

Through the above adjustment, the heat energy of the process warm-air and the feed liquid are sufficiently absorbed by the tobacco shred, the moisture removing air flow is reduced from 2650 m3/h to 318 m3/h, greatly reducing the wastage of the energy and the feed liquid. The condensed water collecting pipe is provided in the air outlet to eliminate the event of the condensed water going into the feed roller with the process warm-air, no wet mass and water staining tobacco is found, with the amount of tobacco shred affixing the roller being significantly reduced. The moisture content standard deviation of the outlet tobacco shred is only 0.10, and the outlet temperature standard deviation is only 0.15, improving the effectiveness and uniformity of the heat energy and the feed liquid absorption of tobacco shred significantly. At the same time, the tobacco shred wet mass and scaling is solved, and greatly improving the sensory quality of tobacco shred.

Finally, it should be understood that, the above mentioned embodiments are disclosed only for illustrative purposes and not limitative. Although the invention is described in detail with reference to the preferred embodiments, those skilled in the art will appreciate that modifications could be made for the specific implementation or equivalent substitution could be made for part of technical features without departing from spirit of the technical solution of the invention, all of which should be included in the scope of the claimed technical solution of the present invention.