阅读说明：本技术 一种箱装片烟局部水分脱除方法及脱除设备 (Method and equipment for removing local moisture of case-packed tobacco flakes ) 是由 刘嫣红 高启 胡海林 雷登文 华平 于 2020-12-21 设计创作，主要内容包括：本发明涉及一种箱装片烟局部水分脱除方法及脱除设备,该箱装片烟局部水分脱除方法包括步骤：1)干燥热风预热；2)启动射频加热同时用干燥热风辅助加热直至达到加热目标温度；3)腔体抽真空,在达到目标真空度后,保持第一预设时间；4)恢复常压；5)再次启动射频加热并用干燥热风辅助加热,并保持第二预设时间,达到预设加热次数则停止通入干燥热风并停止射频加热,否则返回步骤3)；6)抽真空,在达到目标真空度后,保持第三预设时间；7)通入干燥冷风并持续第四预设时间,若降至目标结束温度,则结束,否则返回步骤6)。本发明可以达到快速脱除箱装片烟局部区域水分,并有效避免对箱内未受潮区域片烟的品质造成不良影响的目的。(The invention relates to a method and equipment for removing local moisture of boxed tobacco sheets, wherein the method for removing the local moisture of the boxed tobacco sheets comprises the following steps: 1) preheating dry hot air; 2) starting radio frequency heating and simultaneously using dry hot air for auxiliary heating until the heating target temperature is reached; 3) vacuumizing the cavity, and keeping the cavity for a first preset time after the target vacuum degree is reached; 4) recovering the normal pressure; 5) starting the radio frequency heating again, using dry hot air for auxiliary heating, keeping the second preset time, stopping introducing the dry hot air and stopping the radio frequency heating when the preset heating times are reached, and otherwise, returning to the step 3); 6) vacuumizing, and keeping for a third preset time after the target vacuum degree is reached; 7) and (5) introducing dry cold air and continuing for a fourth preset time, if the temperature is reduced to the target end temperature, ending, and if the temperature is not reduced to the target end temperature, returning to the step 6). The invention can achieve the purposes of quickly removing the moisture in the local area of the packaged tobacco flakes and effectively avoiding the adverse effect on the quality of the tobacco flakes in the damp-free area in the box.)

1. A method for removing moisture from the local parts of case-packed tobacco sheets is characterized by comprising the following steps:

1) putting the boxed tobacco sheets into a cavity which is provided with an air inlet and an air outlet and can be subjected to radio frequency heating, introducing dry hot air into the cavity, preheating the boxed tobacco sheets, and entering the step 2 after the humidified area of the boxed tobacco sheets reaches a preheating target temperature;

2) carrying out radio frequency heating on the boxed tobacco sheets while introducing dry hot air, recording the current radio frequency heating times, and entering the step 3 after the humidified area reaches the heating target temperature;

3) stopping introducing dry hot air, stopping the radio frequency heating, sealing the air inlet and the air outlet, vacuumizing the cavity, keeping the vacuum degree in the cavity for a first preset time after the vacuum degree in the cavity reaches a target vacuum degree, and then entering the step 4);

4) opening the air inlet and recovering the normal pressure in the cavity, and then entering the step 5);

5) opening the air outlet, carrying out radio frequency heating on the boxed tobacco sheets while introducing dry hot air, keeping for a second preset time, recording the current radio frequency heating times, stopping introducing the dry hot air and stopping the radio frequency heating if the current radio frequency heating times reach the preset heating times, and entering the step 6), or returning to the step 3);

6) closing the air inlet and the air outlet, vacuumizing the cavity, keeping the vacuum degree in the cavity for a third preset time after the vacuum degree in the cavity reaches a target vacuum degree, opening the air inlet, recovering the normal pressure in the cavity, and then entering the step 7);

7) and opening the air outlet, introducing dry cold air into the cavity for a fourth preset time, if the central temperature of the boxed tobacco sheets is not greater than the target end temperature, ending, and otherwise, returning to the step 6).

2. The method for locally removing moisture from boxed tobacco sheets according to claim 1, wherein the first preset time is 3 to 15min, the second preset time is 2 to 4min, the third preset time is 3 to 15min, the fourth preset time is 3 to 20min, and the preset heating times are 2 to 10.

3. The method for locally removing moisture from boxed tobacco sheets according to claim 1, wherein the target preheating temperature is 20 ℃ to 30 ℃, the target heating temperature is 45 ℃, the target vacuum degree is-90 kPa, and the target finishing temperature is 30 ℃.

4. The utility model provides a local moisture desorption equipment of case dress piece cigarette which characterized in that includes:

the device comprises a vacuum tank (1) with an air inlet and an air outlet, wherein the vacuum tank (1) is internally provided with a hollow cavity for accommodating boxed tobacco sheets (3);

a temperature sensor (18) for inserting inside the boxed tobacco lamina (3) to measure the temperature of the boxed tobacco lamina;

an air inlet pipe (16) connected with the air inlet;

the hot and cold air pipe is formed by connecting cold air branch pipes (14) and hot air branch pipes (13) in parallel, one end of the cold and hot air pipe is an inlet main pipe, the other end of the cold and hot air pipe is an outlet main pipe, the outlet main pipe is connected with the air inlet pipe (16), one ends of the cold air branch pipes (14) close to the inlet main pipe are provided with first switch valves (11), one ends of the hot air branch pipes (13) close to the inlet main pipe are provided with second switch valves (10), and heating devices are arranged in the hot air branch pipes (13);

the fan (9) is connected with the inlet main pipe of the cold and hot air pipe;

the two radio frequency electrode plates (2) are arranged in the cavity at intervals, and the radio frequency electrode plates (2) are electrically connected with a high-frequency voltage generator (17);

with exhaust pipe (4) that the air outlet links to each other, exhaust pipe (4) have with the first export of atmosphere intercommunication and with the second export of vacuum pump (7) intercommunication, first export is provided with third ooff valve (5), the second export is provided with fourth ooff valve (6).

5. The apparatus for partial moisture removal from boxed tobacco sheets according to claim 4, wherein the air inlet of the fan (9) is further connected with a dehumidifier (8).

6. The apparatus for partial moisture removal from boxed tobacco sheets according to claim 4, wherein the heating means is an electric heating wire (12) spirally coiled in the hot air branch pipe.

7. Apparatus for localized moisture removal of boxed lamina as in claim 4, wherein the temperature sensor (18) has at least two insertion ends, one of which is intended to be inserted into the affected part of the boxed lamina (3) and the other of which is intended to be inserted into the central part of the boxed lamina (3).

8. The equipment for removing the partial moisture of the boxed tobacco sheets according to claim 4, wherein the air inlet and the air outlet are respectively arranged on the left end surface and the right end surface of the vacuum tank (1), and the front end surface and the rear end surface of the vacuum tank (1) are provided with door bodies for the inlet and the outlet of the boxed tobacco sheets.

9. The apparatus of claim 8, wherein the door is actuated by a hydraulic cylinder to open and close.

10. The apparatus for localized moisture removal of boxed tobacco sheets according to claim 8, wherein the end of the vacuum tank (1) provided with the air inlet is further provided with an air flow distributor (15) to distribute the air flow evenly within the cavity.

Technical Field

The invention relates to the technical field of agricultural product drying, in particular to a method and equipment for removing local moisture of case-packed tobacco flakes.

Background

As a raw material of tobacco industry, the boxed tobacco flakes can absorb water and become damp and mildewed in the alcoholization and fermentation process, the loss of the tobacco flakes is light, the grade of the tobacco leaves is reduced, and the tobacco leaves cannot be used at all. After the tobacco flakes mildew, the contents of the tobacco flakes are rapidly decomposed, normal structures and the contents are damaged, the appearance color is dark, the original fragrance disappears, strong mildew acid odor is emitted, the taste is seriously deteriorated, the irritation is increased, the tobacco flakes are bitter and dry when being sucked, the tobacco flakes cannot enter the throat, the toughness and the elasticity are greatly reduced, and when the tobacco flakes mildew seriously, the tobacco flakes are completely changed into black, dirty and rotten substances with stink, so that the use value is lost.

Through field research, the boxed tobacco sheets usually absorb water and are affected with damp in a local area, the damp parts are mostly positioned on the bottom surface and the side surface close to the bottom surface of the boxed tobacco sheets, most mildewed tobacco sheets are concentrated on the bottom surface, the water content of other parts of the boxed tobacco sheets, particularly the central part of the boxed tobacco sheets is normal (the water content is approximately equal to 11 percent), and the mildewing hardly occurs, so that the local damped tobacco sheets need to be dehydrated, and meanwhile, the tobacco sheets in the non-damp area are not heated or dehydrated as much as possible.

Therefore, the technical problem to be solved by the technical staff in the field is needed to realize the selective dehydration and mildew-proof treatment of the local moisture-affected area of the boxed tobacco strips and avoid the adverse effect on the quality of the tobacco strips in the non-moisture area in the box.

Disclosure of Invention

One of the purposes of the invention is to provide a method for removing moisture from the local parts of boxed tobacco sheets so as to realize selective dehydration and mildew-proof treatment of the moistured parts of the boxed tobacco sheets and avoid or reduce the adverse effects on the moistureless tobacco sheets in the box.

The invention also aims to provide a device for removing the local moisture of the boxed tobacco sheets, so that the device can be used for implementing the method for removing the local moisture of the boxed tobacco sheets.

In order to achieve the aim, the method for removing the partial moisture of the boxed tobacco sheets provided by the invention comprises the following steps:

1) putting the boxed tobacco sheets into a cavity which is provided with an air inlet and an air outlet and can be subjected to radio frequency heating, introducing dry hot air into the cavity, preheating the boxed tobacco sheets, and entering the step 2 after the humidified area of the boxed tobacco sheets reaches a preheating target temperature;

2) carrying out radio frequency heating on the boxed tobacco sheets while introducing dry hot air, recording the current radio frequency heating times, and entering the step 3 after the humidified area reaches the heating target temperature;

3) stopping introducing dry hot air, stopping the radio frequency heating, sealing the air inlet and the air outlet, vacuumizing the cavity, keeping the vacuum degree in the cavity for a first preset time after the vacuum degree in the cavity reaches a target vacuum degree, and then entering the step 4);

4) opening the air inlet and recovering the normal pressure in the cavity, and then entering the step 5);

5) opening the air outlet, carrying out radio frequency heating on the boxed tobacco sheets while introducing dry hot air, keeping for a second preset time, recording the current radio frequency heating times, stopping introducing the dry hot air and stopping the radio frequency heating if the current radio frequency heating times reach the preset heating times, and entering the step 6), or returning to the step 3);

6) closing the air inlet and the air outlet, vacuumizing the cavity, keeping the vacuum degree in the cavity for a third preset time after the vacuum degree in the cavity reaches a target vacuum degree, opening the air inlet, recovering the normal pressure in the cavity, and then entering the step 7);

7) and opening the air outlet, introducing dry cold air into the cavity for a fourth preset time, if the central temperature of the boxed tobacco sheets is not greater than the target end temperature, ending, and otherwise, returning to the step 6).

Preferably, the first preset time is 3-15 min, the second preset time is 2-4 min, the third preset time is 3-15 min, the fourth preset time is 3-20 min, and the preset heating frequency is 2-10.

Preferably, the target preheating temperature is 20-30 ℃, the target heating temperature is 45 ℃, the target vacuum degree is-90 kPa, and the target finishing temperature is 30 ℃.

The invention discloses a local moisture removing device for boxed tobacco sheets, which comprises:

the vacuum tank is provided with an air inlet and an air outlet, and a hollow cavity is arranged inside the vacuum tank to accommodate the boxed tobacco sheets;

a temperature sensor for inserting into the interior of the boxed tobacco lamina to measure the temperature of the boxed tobacco lamina;

the air inlet pipe is connected with the air inlet;

the hot and cold air pipes are formed by connecting cold air branch pipes and hot air branch pipes in parallel, one end of each cold and hot air pipe is an inlet main pipe, the other end of each cold and hot air pipe is an outlet main pipe, the outlet main pipe is connected with the air inlet pipe, one ends of the cold air branch pipes, which are close to the inlet main pipes, are provided with first switch valves, one ends of the hot air branch pipes, which are close to the inlet main pipes, are provided with second switch valves, and heating devices are arranged in the hot air;

the fan is connected with the inlet main pipe of the cold and hot air pipe;

the two radio frequency electrode plates are arranged in the cavity at intervals and are electrically connected with the high-frequency voltage generator;

with the exhaust pipe that the air outlet links to each other, the exhaust pipe has the first export with the atmosphere intercommunication and exports with the second of vacuum pump intercommunication, the first export is provided with the third ooff valve, the second export is provided with the fourth ooff valve.

Preferably, the air inlet of the fan is also connected with a dehumidifying device.

Preferably, the heating device is a heating wire spirally coiled in the hot air branch pipe.

Preferably, the temperature sensor has at least two insertion ends, wherein one insertion end is used for inserting the damp part of the boxed tobacco lamina, and the other insertion end is used for inserting the central part of the boxed tobacco lamina.

Preferably, the air inlet and the air outlet are respectively arranged on the left end face and the right end face of the vacuum tank, and door bodies for the boxed tobacco sheets to enter and exit are arranged on the front end face and the rear end face of the vacuum tank.

Preferably, the door body is driven by a hydraulic cylinder to realize opening and closing.

Preferably, the vacuum tank is provided with an air flow distributor at one end of the air inlet so as to uniformly distribute air flow in the cavity.

The invention discloses a method for removing partial moisture of boxed sheet tobacco, which comprises the following steps of preheating a moisture affected area of the boxed sheet tobacco by dry hot air, then carrying out radio frequency heating on the boxed sheet tobacco while introducing the dry hot air, and circulating for a preset time according to the following mode after the moisture affected area reaches a heating target temperature: vacuumizing a cavity in which the boxed tobacco sheets are arranged and keeping the cavity for a first preset time, recovering the cavity to normal pressure, introducing dry hot air and simultaneously carrying out radio frequency heating on the boxed tobacco sheets and keeping the cavity for a second preset time until the circulation for a preset number of times is completed; the cooling cycle is then performed as follows: vacuumizing the cavity and keeping the cavity for a third preset time, recovering the cavity to normal pressure, introducing dry cold air to cool the boxed tobacco sheets and keeping the fourth preset time until the central temperature of the boxed tobacco sheets is reduced to a target ending temperature.

The invention has the beneficial effects that: the auxiliary drying hot air is adopted to preheat the damped area at the bottom of the boxed sheet tobacco, so that the temperature of the damped area of the boxed sheet tobacco is higher than that of the damp-free area, according to the characteristic of radio frequency selective heating, the temperature in the boxed sheet tobacco is higher, the damp-free area with higher moisture content can absorb more radio frequency energy, the temperature rise rate of the damped sheet tobacco in the radio frequency heating process is far higher than that of the damp-free sheet tobacco with lower initial temperature and lower moisture content, the purpose of quickly dehydrating the local damped area in a short time can be realized, the damp-free area is ensured at the same time, particularly, the temperature rise of the central part of the boxed sheet tobacco is smaller, and the quality of the sheet tobacco in the area cannot be adversely affected.

Meanwhile, the radio frequency heating has the advantage of large penetration depth, and the whole uniform temperature rise of a damped area at the bottom of the boxed tobacco sheets can be ensured. And after the moistened sheet tobacco reaches the heating target temperature, removing the moisture in the moistened area of the boxed sheet tobacco by vacuumizing. Through the normal-pressure hot air auxiliary radio frequency heating treatment and the pulsating circulation of vacuum moisture removal, moisture in the damp area of the boxed tobacco sheets is removed quickly, the purpose of mold prevention is achieved, and the tobacco sheets which are not damped are ensured not to be heated and dehydrated basically, so that over-drying or adverse effects on the quality of the tobacco sheets are avoided effectively.

Drawings

FIG. 1 is a schematic flow chart of a method for removing moisture from packaged tobacco lamina disclosed in the embodiments of the present invention;

FIG. 2 is a schematic structural diagram of a local moisture removal device for boxed tobacco lamina disclosed in the embodiment of the invention.

The vacuum box comprises a vacuum tank 1, a radio-frequency electrode plate 2, a box body 3, an exhaust pipe 4, a third switch valve 5, a fourth switch valve 6, a vacuum pump 7, a dehumidifying device 8, a fan 9, a second switch valve 10, a first switch valve 11, an electric heating wire 12, a hot air branch pipe 13, a cold air branch pipe 14, an air flow distributor 15, an air inlet pipe 16, a high-frequency voltage generator 17 and a temperature sensor 18.

Detailed Description

One of the cores of the invention is to provide a method for removing the local moisture of the boxed tobacco sheets so as to realize the selective dehydration and mildew-proof treatment of the moistured parts of the boxed tobacco sheets and simultaneously avoid or reduce the adverse effects on the moistureless tobacco sheets in the box.

The invention also provides equipment for removing the local moisture of the boxed tobacco sheets, so that the equipment can be used for implementing the method for removing the local moisture of the boxed tobacco sheets.

Referring to fig. 1, the method for removing moisture from the packaged tobacco lamina disclosed in the present invention comprises the following steps:

s1) preheating dry hot air;

specifically, the boxed tobacco sheets are placed into a cavity capable of being heated by radio frequency, the cavity is provided with an air inlet and an air outlet, then dry hot air is introduced into the cavity from the air inlet, the dry hot air is led out from the air outlet, the boxed tobacco sheets are preheated in such a way, whether the temperature of a damped area of the boxed tobacco sheets reaches a preheating target temperature or not is judged, and the step S2 is carried out after the temperature of the damped area reaches the preheating target temperature, or the step S1 is carried out continuously);

s2) starting radio frequency heating and simultaneously carrying out auxiliary heating by adopting dry hot air;

specifically, in the step, dry hot air is introduced and radio frequency heating is carried out at the same time, the radio frequency heating times are recorded while heating is carried out, whether the damped area of the boxed tobacco sheet reaches the heating target temperature or not is judged, if yes, the step S3 is carried out, and if not, the step S2 is continuously carried out);

s3) vacuumizing;

specifically, the introduction of dry hot air is stopped, the radio frequency heating is stopped, the air inlet and the air outlet are closed, the cavity is vacuumized, whether the vacuum degree in the cavity reaches the target vacuum degree is judged, if yes, the target vacuum degree is kept for a first preset time, and then the step S4 is executed, and if not, the step S3 is continuously executed);

s4) recovering the normal pressure;

specifically, opening the air inlet to restore the normal pressure in the cavity, and then entering step S5);

s5) starting the radio frequency heating again and simultaneously adopting dry hot air for auxiliary heating;

specifically, the air outlet is opened, the drying hot air is preheated and simultaneously subjected to radio frequency heating again, the second preset time is kept, then the current radio frequency heating frequency is recorded, if the current radio frequency heating frequency reaches the preset heating frequency, the introduction of the drying hot air is stopped, the radio frequency heating is stopped, and the step S6 is executed, otherwise, the step S3 is executed again);

s6), vacuumizing, keeping for a third preset time after the target vacuum degree is reached, and recovering normal pressure;

specifically, the air inlet and the air outlet are closed, the cavity is vacuumized, after the vacuum degree in the cavity reaches the target vacuum degree, the air inlet is opened after the third preset time is kept so as to restore the normal pressure in the cavity, and then the step S7 is performed;

s7) introducing cold air to cool for a fourth preset time;

specifically, the air outlet is opened, cold air (namely, dry cold air) is introduced into the cavity for a fourth preset time, if the central temperature of the packaged tobacco sheets is reduced to the target ending temperature, the operation is ended, and if not, the operation returns to the step S6).

According to the embodiment, the local moisture removal method for the boxed sheet tobacco, disclosed by the invention, comprises the steps of preheating the moisture affected area of the boxed sheet tobacco through dry hot air, then carrying out radio frequency heating on the boxed sheet tobacco while introducing the dry hot air, and circulating for a preset number of times according to the following mode after the moisture affected area reaches the heating target temperature: vacuumizing a cavity in which the boxed tobacco sheets are arranged and keeping the cavity for a first preset time, recovering the cavity to normal pressure, introducing dry hot air and simultaneously carrying out radio frequency heating on the boxed tobacco sheets and keeping the cavity for a second preset time until the circulation for a preset number of times is completed; the cooling cycle is then performed as follows: vacuumizing the cavity and keeping the cavity for a third preset time, recovering the cavity to normal pressure, introducing dry cold air to cool the boxed tobacco sheets and keeping the fourth preset time until the central temperature of the boxed tobacco sheets is reduced to a target ending temperature.

According to the invention, auxiliary dry hot air is adopted to preheat the damped area at the bottom of the boxed sheet tobacco, so that the temperature of the damped area of the boxed sheet tobacco is higher than that of the damp area, according to the characteristic of radio frequency selective heating, the damped area with higher temperature and higher water content in the boxed sheet tobacco can absorb more radio frequency energy, and the temperature rise rate of the damped sheet tobacco is far higher than that of the damp sheet tobacco with lower initial temperature and lower water content in the radio frequency heating process, thereby realizing the purpose of quickly dehydrating the local damped area in a short time, ensuring that the temperature rise of the damp area, especially the central part of the boxed sheet tobacco is smaller, and further not causing adverse effect on the quality of the sheet tobacco in the area.

Meanwhile, the radio frequency heating has the advantage of large penetration depth, and the whole uniform temperature rise of a damped area at the bottom of the boxed tobacco sheets can be ensured. And after the moistened sheet tobacco reaches the heating target temperature, removing the moisture in the moistened area of the boxed sheet tobacco by vacuumizing. Through the normal-pressure hot air auxiliary radio frequency heating treatment and the pulsating circulation of vacuum moisture removal, moisture in the damp area of the boxed tobacco sheets is removed quickly, the purpose of mold prevention is achieved, and the tobacco sheets which are not damped are ensured not to be heated and dehydrated basically, so that over-drying or adverse effects on the quality of the tobacco sheets are avoided effectively.

As can be understood by those skilled in the art, according to the specification of the boxed tobacco flakes and the type of the tobacco flakes, the first preset time, the second preset time, the third preset time, the fourth preset time and the preset heating times can be adjusted accordingly, in one embodiment of the disclosure, the first preset time is 3min to 15min, the second preset time is 2min to 4min, the third preset time is 3min to 15min, the fourth preset time is 3min to 20min, and the preset heating times are 2min to 10 min

According to different types of the sheet tobacco, parameters such as preheating target temperature, heating target temperature, target vacuum degree, target ending temperature and the like also need to be adjusted adaptively, in one embodiment disclosed by the invention, the preheating target temperature is that the temperature of a moisture affected area of the boxed sheet tobacco reaches 20-30 ℃, the heating target temperature is that the temperature of the moisture affected area of the boxed sheet tobacco reaches 45 ℃, the target vacuum degree is-90 kPa, and the target ending temperature is that the central temperature of the boxed sheet tobacco is not more than 30 ℃.

As shown in fig. 2, the embodiment of the invention also discloses a box-packed tobacco local moisture removing device, which comprises a vacuum tank 1, a temperature sensor 18, an air inlet pipe 16, a cold and hot air pipe, a fan 9, a radio frequency electrode plate 2 and an exhaust pipe 4, wherein the vacuum tank 1 is provided with an air inlet and an air outlet, the interior of the vacuum tank 1 is a hollow cavity so as to accommodate the box-packed tobacco 3 through the cavity, the temperature sensor 18 is used for being inserted into the box-packed tobacco 3 to measure the temperature, the air inlet pipe 16 is communicated with the air inlet of the vacuum tank 1, the exhaust pipe 4 is communicated with the air outlet of the vacuum tank 1, the exhaust pipe 4 is provided with a first outlet communicated with the atmosphere and a second outlet communicated with a vacuum pump 7, the cold and hot air pipe is formed by connecting a cold air branch pipe 14 and a hot air branch pipe 13 in parallel, one end of the cold and hot air pipes is an inlet main pipe, one end of the cold air branch pipe 14 close to the inlet header pipe is provided with a first switch valve 11, one end of the hot air branch pipe 13 close to the inlet header pipe is provided with a second switch valve 10, a first outlet of the exhaust pipe 4 is provided with a third switch valve 5, a second outlet is provided with a fourth switch valve 6, a heating device is further arranged in the hot air branch pipe 13, the fan 9 is connected with the inlet header pipe of the cold and hot air pipe, the number of the radio frequency electrode plates 2 can be two or more, as shown in fig. 2, the two radio frequency electrode plates 2 are arranged in the cavity at intervals, and the two radio frequency electrode plates 2 are electrically connected with the high-frequency voltage generator 17.

Further optimize above-mentioned scheme, in the case local moisture desorption equipment of sheet tobacco disclosed in this embodiment, the air intake department of fan 9 still is connected with dehydrating unit 8 to guarantee to let in the dryness fraction of the hot-blast and cold wind in the cavity.

Those skilled in the art will appreciate that the type of the heating means in the hot blast branch pipe 13 is not limited to one, and heating means such as a heating pipe, a heating wire, etc. may be used, and in the present embodiment, the heating means is embodied as the heating wire 12 spirally coiled in the hot blast branch pipe 13.

In one embodiment, the temperature sensor 18 is an optical fiber temperature sensor, and has at least two insertion ends, wherein one insertion end is used for inserting the moisture affected part of the boxed tobacco lamina 3, and the other insertion end is used for inserting the central position of the boxed tobacco lamina 3, so that the moisture of the tobacco lamina in the moisture affected area of the boxed tobacco lamina 3 can be removed, the temperature of the tobacco lamina in the central position of the boxed tobacco lamina 3 can be monitored, and the adverse effect on the tobacco lamina quality caused by the overhigh temperature of the non-moisture affected area of the boxed tobacco lamina 3 can be avoided.

In the equipment for removing moisture from the local portion of boxed tobacco sheets disclosed in the embodiment of the invention, the air inlet and the air outlet are respectively arranged on the left end surface and the right end surface of the vacuum tank 1, as shown in fig. 2, the front end surface and the rear end surface of the vacuum tank 1 are provided with door bodies for the boxed tobacco sheets 3 to enter and exit, and it can be understood that the vacuum tank 1 can be a columnar tank body or a cubic tank body.

In order to improve the degree of automation of local moisture desorption equipment of case dress sheet tobacco, the door body that two terminal surfaces set up around vacuum tank 1 in this embodiment passes through the pneumatic cylinder drive to realize the automation of the door body and open and close, of course, the door body still can provide cylinder or motor and drive, does not do the restriction to this in this application document.

Referring to fig. 2, in order to ensure that the air flow can be uniformly distributed in the vacuum tank 1, in this embodiment, an air flow distributor 15 is further disposed at an air inlet end of the vacuum tank 1, the air flow distributor 15 has an air inlet end and an air outlet end, the air inlet end is used for connecting with an air inlet pipe 16, and the air outlet end is composed of a plurality of air outlet holes uniformly distributed on the cross section of the vacuum tank 1.

When the box-packed local moisture removal equipment for the tobacco sheets disclosed by the embodiment is used for removing the local moisture of the tobacco sheets, the method can be carried out according to the following steps:

s1) putting the boxed sheet tobacco 3 into a vacuum tank 1, wherein the vacuum tank 1 is provided with an air inlet and an air outlet, opening a second switch valve 10 and a third switch valve 5, closing a first switch valve 11 and a fourth switch valve 6, then starting a fan 9 and an electric heating wire 12, introducing dry hot air into the vacuum tank 1 from the air inlet, leading out the dry hot air from the air outlet, preheating the boxed sheet tobacco 3 in such a way, judging whether the temperature of a damped area of the boxed sheet tobacco 3 reaches a preheating target temperature through a temperature sensor 18, if so, entering a step S2), and if not, continuing to execute the step S1);

s2) when dry hot air is introduced, the radio frequency generator 17 is started, the box-packed tobacco strips 3 are subjected to radio frequency heating through the radio frequency electrode plate 2, the radio frequency heating times are recorded while heating, whether the damped area of the box-packed tobacco strips 3 reaches the heating target temperature is judged through the temperature sensor 18, if yes, the step S3 is carried out, and if not, the step S2 is continuously carried out);

s3) closing the fan 9, the heating wire 12 and the radio frequency generator 17, stopping introducing the dry hot air and stopping radio frequency heating, closing the second switch valve 10 and the third switch valve 5, closing the air inlet and the air outlet, opening the fourth switch valve 6, starting the vacuum pump 7 to vacuumize the vacuum tank 1, judging whether the vacuum degree in the vacuum tank 1 reaches the target vacuum degree, if so, closing the fourth switch valve 6, keeping the target vacuum degree for a first preset time, and then entering the step S4), and if not, continuing to execute the step S3);

s4) opening the first switching valve 11 and returning the inside of the vacuum tank 1 to the normal pressure, and then proceeds to step S5);

s5) opening the second switch valve 10 and the third switch valve 5, closing the first switch valve 11, then starting the fan 9, the heating wire 12 and the radio frequency generator 17, carrying out radio frequency heating on the boxed tobacco strips 3 through the radio frequency electrode plate 2 while introducing dry hot air, keeping a second preset time, then recording the current radio frequency heating frequency, if the current radio frequency heating frequency reaches the preset heating frequency, closing the fan 9, the heating wire 12 and the radio frequency generator 17, stopping introducing the dry hot air and stopping the radio frequency heating, and entering the step S6), otherwise, returning to the step S3);

s6) closing the second switch valve 10 and the third switch valve 5, closing the air inlet and the air outlet, opening the fourth switch valve 6, starting the vacuum pump 7 to vacuumize the vacuum tank 1, closing the fourth switch valve 6 and keeping a third preset time after the vacuum degree in the vacuum tank 1 reaches a target vacuum degree, opening the first switch valve 11 to enable the vacuum tank 1 to recover normal pressure, and then entering the step S7);

s7) opening the third switch valve 5, starting the fan 9 to introduce cold air into the vacuum tank 1 for a fourth preset time, if the temperature sensor 17 indicates that the temperature of the boxed tobacco 3 is reduced to the target ending temperature, ending, otherwise, returning to the step S6).

It should be noted that the same technical terms in different embodiments of the present disclosure have the same meaning, and those skilled in the art can refer to the technical terms from embodiment to embodiment.

The method and the equipment for removing the partial moisture of the boxed tobacco sheets are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.