CN111609692A - Microwave vacuum drying device, control method and application - Google Patents
Microwave vacuum drying device, control method and application Download PDFInfo
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- CN111609692A CN111609692A CN201910131485.0A CN201910131485A CN111609692A CN 111609692 A CN111609692 A CN 111609692A CN 201910131485 A CN201910131485 A CN 201910131485A CN 111609692 A CN111609692 A CN 111609692A
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- 238000001291 vacuum drying Methods 0.000 title claims abstract description 32
- 238000000034 method Methods 0.000 title claims abstract description 30
- 239000000463 material Substances 0.000 claims abstract description 106
- 238000001035 drying Methods 0.000 claims abstract description 80
- 230000007246 mechanism Effects 0.000 claims abstract description 44
- 230000005855 radiation Effects 0.000 claims abstract description 23
- 238000005086 pumping Methods 0.000 claims abstract description 19
- 238000002955 isolation Methods 0.000 claims description 27
- 241000208125 Nicotiana Species 0.000 claims description 19
- 235000002637 Nicotiana tabacum Nutrition 0.000 claims description 19
- 238000001514 detection method Methods 0.000 claims description 14
- 230000002093 peripheral effect Effects 0.000 claims description 5
- 238000009423 ventilation Methods 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 238000010438 heat treatment Methods 0.000 description 7
- 230000008569 process Effects 0.000 description 7
- 239000000523 sample Substances 0.000 description 7
- 238000012360 testing method Methods 0.000 description 6
- 238000012546 transfer Methods 0.000 description 6
- 238000009529 body temperature measurement Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000004321 preservation Methods 0.000 description 3
- 239000011358 absorbing material Substances 0.000 description 2
- 239000000498 cooling water Substances 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000013519 translation Methods 0.000 description 2
- SNICXCGAKADSCV-JTQLQIEISA-N (-)-Nicotine Chemical compound CN1CCC[C@H]1C1=CC=CN=C1 SNICXCGAKADSCV-JTQLQIEISA-N 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 235000019504 cigarettes Nutrition 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000002276 dielectric drying Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 229960002715 nicotine Drugs 0.000 description 1
- SNICXCGAKADSCV-UHFFFAOYSA-N nicotine Natural products CN1CCCC1C1=CC=CN=C1 SNICXCGAKADSCV-UHFFFAOYSA-N 0.000 description 1
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B11/00—Machines or apparatus for drying solid materials or objects with movement which is non-progressive
- F26B11/18—Machines or apparatus for drying solid materials or objects with movement which is non-progressive on or in moving dishes, trays, pans, or other mainly-open receptacles
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B23/00—Heating arrangements
- F26B23/04—Heating arrangements using electric heating
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B25/00—Details of general application not covered by group F26B21/00 or F26B23/00
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B25/00—Details of general application not covered by group F26B21/00 or F26B23/00
- F26B25/008—Seals, locks, e.g. gas barriers or air curtains, for drying enclosures
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B25/00—Details of general application not covered by group F26B21/00 or F26B23/00
- F26B25/009—Alarm systems; Safety sytems, e.g. preventing fire and explosions
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B25/00—Details of general application not covered by group F26B21/00 or F26B23/00
- F26B25/06—Chambers, containers, or receptacles
- F26B25/14—Chambers, containers, receptacles of simple construction
- F26B25/18—Chambers, containers, receptacles of simple construction mainly open, e.g. dish, tray, pan, rack
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B5/00—Drying solid materials or objects by processes not involving the application of heat
- F26B5/04—Drying solid materials or objects by processes not involving the application of heat by evaporation or sublimation of moisture under reduced pressure, e.g. in a vacuum
- F26B5/048—Drying solid materials or objects by processes not involving the application of heat by evaporation or sublimation of moisture under reduced pressure, e.g. in a vacuum in combination with heat developed by electro-magnetic means, e.g. microwave energy
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B2200/00—Drying processes and machines for solid materials characterised by the specific requirements of the drying good
- F26B2200/22—Tobacco leaves
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Molecular Biology (AREA)
- Sustainable Development (AREA)
- Drying Of Solid Materials (AREA)
Abstract
The invention discloses a microwave vacuum drying device, a control method and application, wherein the microwave vacuum drying device comprises: a drying chamber having a door body that can be opened and closed; the material tray is arranged inside the drying chamber and is used for bearing materials; the microwave radiation mechanism is arranged inside the drying chamber; the vacuum pump is communicated with the drying chamber through a vacuum pumping pipe; the air release valve is arranged at an air release port on the wall surface of the drying chamber; and the material tray control mechanism controls the material tray to reciprocate in the horizontal direction. According to the microwave drying device, the material tray is controlled to reciprocate in the horizontal direction, so that the materials are uniformly heated in a microwave field, and the drying effect of the materials is improved.
Description
Technical Field
The invention belongs to the field of microwave vacuum drying, and particularly relates to a microwave vacuum drying device, a control method and application.
Background
At present, the sample preparation of domestic cigarette enterprises is to dry tobacco leaves (or tobacco shreds) in an oven at the temperature of not higher than 40 ℃ until the tobacco leaves (or the tobacco shreds) can be twisted into pieces by hands.
In general, tobacco leaves (or cut tobacco) to be detected are dried in an oven for 2 hours by an oven method, and then ground into powder to prepare a sample. At present, the drying time of the oven method is too long, the drying efficiency is low, the sample preparation efficiency is low, and the detection result cannot be fed back to the site in time to guide production.
When drying by an oven method, moisture is evaporated from the surface, the internal moisture is slowly diffused to the surface, energy is transferred from the outside of the material to the inside of the material, the driving force of heat transfer is temperature gradient, usually high external temperature is needed to form the required temperature difference, the driving force of mass transfer is the concentration difference between the inside and the surface of the material, and it can be seen that the heat transfer direction and the mass transfer direction are opposite in common drying.
The present invention has been made in view of this situation.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a microwave vacuum drying device, a control method and application to solve the technical problems of uneven heating of materials, inaccurate temperature measurement and low drying efficiency.
In order to solve the technical problems, the invention adopts the technical scheme that:
a microwave vacuum drying apparatus, the apparatus comprising:
a drying chamber having a door body that can be opened and closed;
the material tray is arranged inside the drying chamber and is used for bearing materials;
the microwave radiation mechanism is arranged inside the drying chamber;
the vacuum pump is communicated with the drying chamber through a vacuum pumping pipe;
the air release valve is arranged at an air release port on the wall surface of the drying chamber;
and the material tray control mechanism controls the material tray to reciprocate in the horizontal direction.
Further, the tray control mechanism includes:
the material tray frame is arranged inside the drying chamber;
the output shaft of the motor is horizontally arranged, and the output shaft of the motor is connected with the material tray frame through a horizontally arranged screw rod and can rotate forwards and backwards;
the tray is positioned on the tray frame.
Further, the charging tray includes:
a three-dimensional frame;
and the ventilation net is fixed in the three-dimensional frame to form a container with side walls and a bottom wall.
Further, the apparatus further comprises:
the feed inlet is arranged on the wall surface of the drying chamber;
the isolation pipe is closed at one end and opened at the other end, the closed end of the isolation pipe is inserted into the drying chamber through the feed-in port, and the outer wall of the isolation pipe is hermetically connected with the edge of the feed-in port;
one end of the microwave antenna is connected with the microwave source, and the other end of the microwave antenna is inserted into the isolation tube through the open end and is arranged inside the drying chamber to form a microwave radiation mechanism.
Furthermore, a convex positioning table is arranged on the outer wall of the isolation tube, and when the outer wall of the isolation tube is hermetically connected with the edge of the feed-in port, the positioning table is abutted to the outer peripheral surface of the feed-in port and is fixedly connected with the outer peripheral surface of the feed-in port.
Further, the apparatus further comprises:
and the temperature sensor is arranged in the material center in the material tray.
Further, the apparatus further comprises:
the control system comprises an automatic control mechanism for automatically controlling the device to operate and a control mechanism for the user to manually control the device to operate.
A control method of a microwave vacuum drying device comprises the following steps: the tray is controlled to reciprocate in the horizontal direction at the time of or after the microwave radiation mechanism is activated.
Further, before or when the microwave radiation mechanism is started, the vacuum pumping pump is started, when the vacuum pumping pump is started, the vacuum degree in the drying chamber is detected, and when or after the detected value of the vacuum degree reaches a first vacuum degree set value, the microwave radiation mechanism is started;
preferably, when the microwave radiation mechanism is started, whether the vacuum degree detection value reaches a second vacuum degree set value higher than the first vacuum degree set value is judged, if yes, the vacuum pumping pump is closed, the vacuum pumping pump is started when the vacuum degree detection value is reduced to a third set value lower than the second vacuum degree set value, and if not, the vacuum pumping pump continues to operate;
more preferably, when the microwave radiation mechanism is started, the temperature of the material center in the material tray is detected, whether the temperature detection value reaches a temperature set value or not is judged, if yes, the microwave source power is reduced, and if not, the microwave source power is increased.
Use of a microwave vacuum drying apparatus as defined above or a control method as defined above in the drying of cut tobacco and/or tobacco leaves.
After adopting the technical scheme, compared with the prior art, the invention has the following beneficial effects:
according to the microwave drying device, the material tray is controlled to reciprocate in the horizontal direction, so that the materials are uniformly heated in a microwave field, and the drying effect of the materials is improved.
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without limiting the invention to the right. It is obvious that the drawings in the following description are only some embodiments, and that for a person skilled in the art, other drawings can be derived from them without inventive effort. In the drawings:
FIG. 1 shows a schematic structural diagram of the apparatus provided by the present invention;
FIG. 2 shows a schematic top view of the apparatus provided by the present invention;
fig. 3 shows a bottom assembly schematic of the device provided by the present invention.
In the figure: 1. the microwave drying device comprises a control system, 2, an isolation pipe, 3, a microwave source, 4, a drying chamber, 5, a temperature sensor, 6, a material tray, 7, a material tray frame, 8, a material tray control mechanism, 9, a cooling water circulation mechanism, 10, an exhaust mechanism, 11, a microwave antenna, 12, a door body, 13, an observation window, 14, a rack, 15, a covering plate, 16, a lighting mechanism, 17, a vacuum meter, 18, an air release valve, 19, a vacuum pump, 20, a high-voltage switch power supply, 21 and an electric control board.
It should be noted that the drawings and the description are not intended to limit the scope of the inventive concept in any way, but to illustrate it by a person skilled in the art with reference to specific embodiments.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and the following embodiments are used for illustrating the present invention and are not intended to limit the scope of the present invention.
In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
As shown in fig. 1 to 3, an embodiment of the present invention introduces a microwave vacuum drying apparatus, including: a drying chamber 4 having an openable/closable door body 12; the material tray 6 is arranged inside the drying chamber 4, and materials are loaded in the material tray 6; the microwave radiation mechanism is arranged inside the drying chamber 4; a vacuum pump 19 communicated with the drying chamber 4 through a vacuum pipe; the air release valve 18 is arranged at an air release port on the wall surface of the drying chamber 4; and the material tray control mechanism 8 controls the material tray 6 to reciprocate in the horizontal direction.
According to the invention, the material tray 6 is controlled to reciprocate in the horizontal direction, so that the material is uniformly heated in the microwave field, and the drying effect of the material is improved.
In some embodiments of the invention, the movement of the material tray 6 is relatively stable, and the material tray 6 do not move relatively, and in other embodiments of the invention, the movement of the material tray 6 is relatively violent, and the material tray 6 move relatively.
The embodiment of the invention also discloses a control method of the microwave vacuum drying device, which comprises the following steps: the tray 6 is controlled to reciprocate in the horizontal direction at the time of or after the microwave radiation mechanism is activated.
The embodiment of the invention also introduces the application of the microwave vacuum drying device or the control method in the tobacco shred and/or tobacco leaf drying.
Example one
As shown in fig. 1 to 3, in the present embodiment, the tray control mechanism 8 includes: the material tray frame 7 is arranged inside the drying chamber 4; the output shaft of the motor is horizontally arranged, and the output shaft of the motor is connected with the material tray frame through a horizontally arranged screw rod and can rotate forwards and backwards; the tray 6 is positioned on the tray holder 7.
The invention realizes the reciprocating motion of the tray rack 7 in the horizontal direction by controlling the positive and negative rotation of the output shaft of the motor, thereby realizing the reciprocating motion of the tray 6 in the horizontal direction.
Among them, a screw is one of the most common mechanical parts. The main function of the screw rod is to convert the rotary motion of the output shaft of the motor into linear motion. Generally, the length of the lead screw is greater than the stroke required for movement, so that the lead screw can reciprocate within a safety stroke. For the occasion that reciprocating motion is needed, a limit sensor, a controller and a control program are generally adopted. After the screw rod nut moves to a limit position in one direction, the reciprocating motion is realized by controlling the rotation direction of the output shaft of the motor. The screw rod of the invention is a structure disclosed in the prior art, and therefore, the details are not repeated, specifically, the screw rod is arranged below the material tray frame 7, the sliding part of the screw rod is connected with the bottom of the material tray frame 7, and the driving part is connected with the output shaft of the motor.
The invention can also make the output shaft of the motor connect with the tray frame 7 through the reciprocating screw rod, and the output shaft of the motor can only rotate forward or only rotate backward.
Preferably, the tray frame 7 includes a horizontally disposed supporting portion and a positioning portion protruding from the upper surface of the supporting portion, the positioning portion is disposed corresponding to the tray 6, so that the tray 6 is placed on the supporting portion and the periphery of the tray is abutted to the positioning portion, and the tray 6 is positioned on the tray frame 7.
In some embodiments of the present invention, the tray frame 7 is a plate-shaped structure without holes, so that the tray frame 7 can receive the material leaked from the tray 6. In other embodiments of the invention, the tray frame 7 is a plate-shaped structure with holes to facilitate the moisture in the material to escape.
Example two
As shown in fig. 1 to 3, the present embodiment is different from the first embodiment in that the tray 6 includes: a three-dimensional frame; and the ventilation net is fixed in the three-dimensional frame to form a container with side walls and a bottom wall.
According to the invention, the bottom wall and the side wall of the material tray 6 are of hollow structures, so that the moisture of the material can be effectively ensured to rapidly escape from the upper part, the lower part and the periphery of the material tray 6 in the drying process, and the rapid and uniform drying of the material can be realized.
The three-dimensional frame may be cylindrical, square or rectangular.
Preferably, the bottom of the tray 6 is provided with at least three spaced feet, so that the bottom of the tray 6 is spaced from the bearing part at a certain distance, so as to facilitate the moisture in the material to escape.
EXAMPLE III
As shown in fig. 1 to 3, the present embodiment is different from the first and second embodiments in that the apparatus further includes: the feed inlet is arranged on the wall surface of the drying chamber 4; the isolation tube 2 is closed at one end and open at the other end, the closed end of the isolation tube 2 is inserted into the drying chamber 4 through the feed-in port, and the outer wall of the isolation tube 2 is hermetically connected with the edge of the feed-in port; and a microwave antenna 11, one end of which is connected with the microwave source 3, and the other end of which is inserted into the isolation tube 2 through the open end and is arranged inside the drying chamber 4 to form a microwave radiation mechanism.
Wherein, the isolation tube 2 is made of non-wave-absorbing material.
The microwave source 3 is isolated from vacuum by arranging the isolation tube 2, so that the danger of high-vacuum discharge generated at the feed-in port is effectively avoided.
Preferably, the outer wall of the isolation tube 2 is provided with a convex positioning table, and when the outer wall of the isolation tube 2 is hermetically connected with the edge of the feed-in port, the positioning table is abutted to the outer peripheral surface of the feed-in port and is fixedly connected with the outer peripheral surface of the feed-in port.
Specifically, the feed-in mouth is located on the 4 lateral walls of drying chamber that are higher than the setting of charging tray 6, and isolation tube 2 is straight tubulose, and it is inside to be inserted isolation tube 2 to be the level setting to drying chamber 4, and the microwave antenna is the linear type, inserts isolation tube 2 inside along isolation tube 2 axis after setting up the microwave antenna level. Wherein, the inner diameter of the isolation tube 2 is larger than the outer diameter of the microwave antenna, and the length of the isolation tube 2 is larger than or equal to the insertion length of the microwave antenna 11.
Preferably, the microwave radiation mechanism is arranged opposite to the material tray 6 in the vertical direction. More preferably, the extending direction of the microwave antenna 11 is perpendicular to the extending direction of the lead screw.
Example four
As shown in fig. 1 to 3, the present embodiment is different from the first to third embodiments in that the apparatus further includes: and the temperature sensor 5 is arranged in the material center in the material tray 6.
According to the invention, the temperature sensor 5 is arranged in the material center, so that the material temperature is more accurately and effectively monitored, and the authenticity and reliability of test data are ensured.
The temperature sensor 5 is a fiber optic temperature sensor.
The device still includes: the control system comprises an automatic control mechanism for automatically controlling the device to operate and a control mechanism for the user to manually control the device to operate.
EXAMPLE five
As shown in fig. 1 to 3, the present embodiment is different from the first to fourth embodiments in that the apparatus further includes: a housing; the air exhaust mechanism 10 is arranged on the shell; a high voltage switch power supply 20 arranged inside the housing; the electric control board 21 is arranged inside the shell; and a cooling water circulation mechanism 9 provided inside the casing.
The housing includes: a frame 14; and a cover plate 15 fixed in the frame 14 to form a housing.
EXAMPLE six
As shown in fig. 1 to 3, the present embodiment is different from the first to fifth embodiments in that the apparatus further includes: a vacuum meter 17 communicated with the detection port on the wall surface of the drying chamber 4 through a pipeline; the observation window 13 is arranged on the door body 12; and an illumination mechanism 16 provided inside the drying chamber 4.
Preferably, the detection port is arranged at the top of the drying chamber 4, and the vacuumizing tube is communicated with the drying chamber 4 through a vacuumizing port at the bottom of the drying chamber 4; more preferably, the detection port is provided near one side during drying, and the evacuation port is provided near the other side opposite to the drying chamber 4.
Preferably, the lighting means 16 are arranged at the top of the drying chamber 4; more preferably, the illuminating mechanism 16 is disposed in vertical correspondence with the tray 6.
EXAMPLE seven
The present embodiment is different from the first to sixth embodiments in that the vacuum pump 19 is started before or at the time of starting the microwave radiation mechanism, the degree of vacuum inside the drying chamber 4 is detected at the time of starting the vacuum pump 19, and the microwave radiation mechanism is started at or after the detected value of the degree of vacuum reaches the first set value of the degree of vacuum.
Preferably, when the microwave radiation mechanism is started, whether the vacuum degree detection value reaches a second vacuum degree set value higher than the first vacuum degree set value is judged, if yes, the vacuum pumping pump 19 is closed, the vacuum pumping pump 19 is started when the vacuum degree detection value is reduced to a third set value lower than the second vacuum degree set value, and if not, the vacuum pumping pump 19 continues to operate.
More preferably, when the microwave radiation mechanism is started, the temperature of the material center in the material tray 6 is detected, whether the temperature detection value reaches a temperature set value or not is judged, if yes, the power of the microwave source 3 is reduced, and if not, the power of the microwave source 3 is increased.
The technical scheme of the invention can also be expressed as follows:
the invention adopts a microwave vacuum drying technology, and the basic principle is as follows: the water molecules belong to polar molecules, the dielectric constant is large, the dielectric loss factor is also large, the microwave absorbing capacity is high, in addition, the boiling point of water in a vacuum environment can be reduced, and the two characteristics of water are utilized to realize that tobacco leaves (or tobacco shreds) with high water content can be quickly dried to a target state in the microwave introduction and high vacuum environment under the working condition that the temperature is controlled to be not higher than 40 ℃. The microwave vacuum drying method is characterized in that the drying method is carried out by taking dielectric as a heat source in a vacuum environment. In the dielectric drying process, heat is generated in the material, and the driving force of mass transfer is mainly a pressure gradient formed by steam rapidly generated in the material. If the material starts to be very wet and the pressure inside the material rises very quickly, liquid may also be removed from the material by the pressure gradient, the higher the initial moisture content, the greater the influence of the pressure gradient on the removal of moisture, i.e. there is a "pumping" effect, driving liquid water and water vapour towards the surface, the same direction of heat and mass transfer in the process, and drying thus proceeds very quickly. The microwave vacuum drying technology has the advantages of uniform heating and high speed; the adjustment is sensitive and convenient to control; selectively heating; the penetration ability is strong, and the nutrient loss is small; cleaning and sanitation; environmental protection of equipment and the like.
The invention provides a microwave vacuum drying device, in particular to a microwave vacuum drying device for preparing tobacco leaf (or tobacco shred) samples in the tobacco industry, the structure sketch of which is shown in figures 1-3, and the microwave vacuum drying device has the characteristics that: the device has the main functions that materials are heated by microwave energy in a vacuum environment, under the condition that the temperature of the materials is not higher than 40 ℃, moisture contained in the materials is quickly evaporated at a lower evaporation temperature and is pumped out by a vacuum pumping pump 19, the materials are dried until the materials can be manually smashed, and the materials are ground to prepare samples for next component detection.
Compared with the prior art, the invention at least has the innovation points that: 1. the microwave vacuum drying device adopts microwave and vacuum technologies, utilizes more accurate and credible optical fiber temperature sensor 5 to measure temperature, is matched with the horizontal swinging motion of materials, realizes the low-temperature drying of materials such as tobacco leaves and the like at the temperature below 40 ℃ through an effective control program, shortens the drying time to be below 1/4 of a standard oven method, and can obviously improve the drying efficiency of the materials. The device has the test conditions of the drying temperature below 100 ℃, greatly shortens the drying time and provides reliable test conditions to explore the influence of different drying temperatures on the sample quality (such as nicotine content, sugar content and the like) in a microwave vacuum environment on the premise of ensuring the quality of the sample to be unchanged or improving the quality, thereby providing reliable data support for the establishment of a new tobacco industry standard of 'sample preparation-microwave vacuum drying method'. The device is also suitable for microwave vacuum drying tests of similar block or large-particle materials, and has wide application prospect. 2. The material tray 6 for containing the materials is innovated to manufacture the material tray 6 for containing the materials after various process tests are carried out on the device, the experience is summarized, the shape can be cylindrical, square or cuboid, the material tray 6 is made into a three-dimensional frame by adopting non-wave-absorbing plates/pipes, the non-wave-absorbing mesh materials are fixed in the three-dimensional frame to form a structure with hollowed side surfaces and bottom surfaces, the rapid escape of water from the top, the bottom and the periphery in the drying process is effectively guaranteed, and the rapid and uniform drying of the materials is realized. 3. The motion mode of the material in a microwave field is innovated in a microwave environment, in order to heat the material uniformly, the common method is to rotate the material, and the method can only adopt non-contact temperature measurement methods such as infrared and the like to measure and control the temperature of the material. The method can only measure the surface temperature of the material, but according to the heating characteristics of the microwave, the microwave directly acts on water molecules in the material, the highest temperature is at the center of the material, and therefore infrared temperature measurement is not accurate. This device is through step motor positive and negative rotation, and the lead screw is rotatory, promotes to carry out parallel translation rather than screw-thread fit's charging tray frame 7, realizes the material translation swing back and forth, ensures the material thermally equivalent in the microwave field, can insert each material center department with optic fibre temperature sensor 5 probe simultaneously, adopts this kind of contact temperature measurement method, more accurate effectual monitoring material temperature, ensures the authenticity and the reliability of test data. 4. The microwave-proof vacuum discharge structure is innovative, under the condition of certain microwave power and loading capacity, the drying process is accelerated by properly improving the vacuum degree, but the danger of breakdown discharge exists in the case of overhigh vacuum degree. The invention adopts the sealing structure made of non-wave-absorbing materials to isolate the microwave source 3 from vacuum, thereby effectively avoiding the danger of high vacuum discharge at the microwave feed inlet. 5. The effective and reliable control system can realize two control modes of manual control and automatic control on the material temperature, the output power of the microwave source 3 and the vacuum degree in the drying chamber 4. Automatic control: after a microwave starting vacuum degree control value, a vacuum degree control range, microwave heating power and heat preservation power, a temperature control range and drying time are set according to process requirements, the microwave starting vacuum degree control value, the vacuum degree control range, the microwave heating power and heat preservation power, the temperature control range and the drying time are started by one key, the output power of the microwave source 3 is automatically adjusted through a PLC program according to real-time material temperature monitoring, the heating or heat preservation process of the material is realized, the automatic control of the material temperature is realized, and the vacuum pumping pump 19 is automatically started and closed to realize the automatic control. Manual control: in the drying process, an operator can control the material temperature and the production efficiency by timely adjusting the output power of the microwave source 3; the vacuum degree in the drying chamber 4 can be controlled by manually turning on and off the vacuum pump 19 at appropriate times or adjusting the vacuum degree control range as required.
The device of the invention has the following working flows: starting a vacuum pumping pump 19, starting the microwave source 3 after the vacuum degree reaches a set value, and simultaneously starting the material tray 6 to swing to raise the temperature of the material; as the vacuum degree is increased to a set value, water in the materials is quickly evaporated, and meanwhile, the vacuum pump 19 continuously pumps the materials; in the process, when the vacuum degree is higher than a set value, the vacuum pumping pump 19 is closed, and the vacuum degree is restarted after being reduced to the set value, and the process is repeated, and the vacuum degree is controlled to be within a set range; the temperature of the material can gradually rise along with the more and more water dispersion loss in the material, the power of the microwave source 3 starts to be reduced according to a set program when the temperature of the material is increased to a set value, the material is ensured not to be over-heated, and the power of the microwave source 3 starts to be increased when the temperature of the material is reduced to the set value. The above steps are repeated until the drying time is reached, the air release valve 18 is opened, and the drying is finished.
Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. A microwave vacuum drying apparatus, characterized in that the apparatus comprises:
a drying chamber having a door body that can be opened and closed;
the material tray is arranged inside the drying chamber and is used for bearing materials;
the microwave radiation mechanism is arranged inside the drying chamber;
the vacuum pump is communicated with the drying chamber through a vacuum pumping pipe;
the air release valve is arranged at an air release port on the wall surface of the drying chamber;
and the material tray control mechanism controls the material tray to reciprocate in the horizontal direction.
2. A microwave vacuum drying apparatus according to claim 1, wherein the tray control mechanism comprises:
the material tray frame is arranged inside the drying chamber;
the output shaft of the motor is horizontally arranged, and the output shaft of the motor is connected with the material tray frame through a horizontally arranged screw rod and can rotate forwards and backwards;
the tray is positioned on the tray frame.
3. A microwave vacuum drying apparatus according to claim 1, wherein the tray comprises:
a three-dimensional frame;
and the ventilation net is fixed in the three-dimensional frame to form a container with side walls and a bottom wall.
4. A microwave vacuum drying apparatus according to claim 1, wherein the apparatus further comprises:
the feed inlet is arranged on the wall surface of the drying chamber;
the isolation pipe is closed at one end and opened at the other end, the closed end of the isolation pipe is inserted into the drying chamber through the feed-in port, and the outer wall of the isolation pipe is hermetically connected with the edge of the feed-in port;
one end of the microwave antenna is connected with the microwave source, and the other end of the microwave antenna is inserted into the isolation tube through the open end and is arranged inside the drying chamber to form a microwave radiation mechanism.
5. A microwave vacuum drying apparatus as claimed in claim 4, wherein the isolation tube is provided with a protruding positioning platform on its outer wall, and when the isolation tube is hermetically connected to the edge of the feeding port, the positioning platform is in contact with and fixedly connected to the outer peripheral surface of the feeding port.
6. A microwave vacuum drying apparatus according to claim 1, wherein the apparatus further comprises:
and the temperature sensor is arranged in the material center in the material tray.
7. A microwave vacuum drying apparatus according to claim 1, wherein the apparatus further comprises:
the control system comprises an automatic control mechanism for automatically controlling the device to operate and a control mechanism for the user to manually control the device to operate.
8. A control method of a microwave vacuum drying device is characterized by comprising the following steps: the tray is controlled to reciprocate in the horizontal direction at the time of or after the microwave radiation mechanism is activated.
9. The control method of a microwave vacuum drying apparatus according to claim 8, wherein the vacuum pump is started before or at the time of starting the microwave radiation mechanism, the degree of vacuum inside the drying chamber is detected at the time of starting the vacuum pump, and the microwave radiation mechanism is started at or after the detected value of the degree of vacuum reaches the first set value of the degree of vacuum;
preferably, when the microwave radiation mechanism is started, whether the vacuum degree detection value reaches a second vacuum degree set value higher than the first vacuum degree set value is judged, if yes, the vacuum pumping pump is closed, the vacuum pumping pump is started when the vacuum degree detection value is reduced to a third set value lower than the second vacuum degree set value, and if not, the vacuum pumping pump continues to operate;
more preferably, when the microwave radiation mechanism is started, the temperature of the material center in the material tray is detected, whether the temperature detection value reaches a temperature set value or not is judged, if yes, the microwave source power is reduced, and if not, the microwave source power is increased.
10. Use of a microwave vacuum drying apparatus according to any of claims 1 to 7 or a control method according to any of claims 8 to 9 for drying cut tobacco and/or tobacco leaves.
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| CN201910131485.0A CN111609692A (en) | 2019-02-22 | 2019-02-22 | Microwave vacuum drying device, control method and application |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113303490A (en) * | 2021-06-15 | 2021-08-27 | 上海恒博自动化设备有限公司 | Heating non-combustion sheet tobacco paper on-line drying device |
| CN114383386A (en) * | 2022-01-22 | 2022-04-22 | 和爱电磁兼容科技(安徽)有限公司 | Surface dehumidification structure for absorbing material |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2791565Y (en) * | 2005-03-13 | 2006-06-28 | 张文华 | Microwave rotary vacuum drier |
| CN203120929U (en) * | 2013-03-07 | 2013-08-14 | 上海镧泰微波设备制造有限公司 | Vacuum microwave drying device for grosvener siraitia |
| CN103411395A (en) * | 2013-08-23 | 2013-11-27 | 太仓市金强家具有限公司 | Safe and unattended microwave vacuum low-temperature wood drying processing device |
| US20170115057A1 (en) * | 2014-06-11 | 2017-04-27 | Enwave Corporation | Microwave vacuum-drying of organic materials |
| CN207066023U (en) * | 2017-08-16 | 2018-03-02 | 江苏先达建设集团有限公司 | A kind of electric drying oven with forced convection with rolling material device |
| KR20180039950A (en) * | 2016-10-11 | 2018-04-19 | 주식회사 한국캐비치 | Microwave Drying Device |
| CN209820074U (en) * | 2019-02-22 | 2019-12-20 | 北京航天试验技术研究所 | Microwave vacuum drying device |
-
2019
- 2019-02-22 CN CN201910131485.0A patent/CN111609692A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2791565Y (en) * | 2005-03-13 | 2006-06-28 | 张文华 | Microwave rotary vacuum drier |
| CN203120929U (en) * | 2013-03-07 | 2013-08-14 | 上海镧泰微波设备制造有限公司 | Vacuum microwave drying device for grosvener siraitia |
| CN103411395A (en) * | 2013-08-23 | 2013-11-27 | 太仓市金强家具有限公司 | Safe and unattended microwave vacuum low-temperature wood drying processing device |
| US20170115057A1 (en) * | 2014-06-11 | 2017-04-27 | Enwave Corporation | Microwave vacuum-drying of organic materials |
| KR20180039950A (en) * | 2016-10-11 | 2018-04-19 | 주식회사 한국캐비치 | Microwave Drying Device |
| CN207066023U (en) * | 2017-08-16 | 2018-03-02 | 江苏先达建设集团有限公司 | A kind of electric drying oven with forced convection with rolling material device |
| CN209820074U (en) * | 2019-02-22 | 2019-12-20 | 北京航天试验技术研究所 | Microwave vacuum drying device |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113303490A (en) * | 2021-06-15 | 2021-08-27 | 上海恒博自动化设备有限公司 | Heating non-combustion sheet tobacco paper on-line drying device |
| CN114383386A (en) * | 2022-01-22 | 2022-04-22 | 和爱电磁兼容科技(安徽)有限公司 | Surface dehumidification structure for absorbing material |
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