Microwave drying device

Abstract

The utility model provides a microwave drying device, which relates to the technical field of microwave drying and comprises a tunnel type microwave dryer, a material conveying belt, two first microwave drying chambers, three second microwave drying chambers and an air inlet. Low-temperature air outlets and low-temperature air outlet pipes are arranged at the tops of the two first microwave drying chambers, and the other ends of the two low-temperature air outlet pipes jointly communicate with an outer exhaust pipe; the top of each second microwave drying chamber is provided with a high-temperature air outlet and a high-temperature air outlet pipe, the other ends of the three high-temperature air outlet pipes jointly communicate with a high-temperature air return pipe, and one end of the high-temperature air return pipe is connected with a circulating fan. By means of the draught fan and the air volume adjusting valve, high-temperature and dry air is reused, the purpose of saving energy is achieved, a single microwave heating mode is changed into a microwave and hot air circulation dual heating mode, materials are dried more thoroughly, and then the production efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of microwave drying, in particular to a microwave drying device. Background Art

[0002] Microwave energy can quickly and evenly heat and dry water-containing substances, and it also causes less damage to vitamins. Therefore, microwave drying has been widely used in the production of mannitol. The principle is that when a dielectric is placed in an alternating electromagnetic field, the molecules with asymmetric charges are stimulated by the alternating electromagnetic field and rotate. Due to the irregular thermal motion of the original molecules inside the material and the interaction between adjacent molecules, the rotation of the molecules is disturbed and restricted, resulting in a "friction effect". As a result, part of the energy is converted into molecular thermal motion function, that is, it is expressed in the form of heat, so that the material is heated.

[0003] The main energy source of microwave is electricity. The power consumption varies according to the moisture content of the material. The moisture content of mannitol after centrifugation is 8%, and the material is sticky. In order to ensure the quality of the final product, the microwave energy consumption must be increased (200kw / t) to effectively control the moisture.

[0004] At present, on the production line, after centrifugation, mannitol is heated by microwave, and the temperature of the front section of the outlet air is 30-35°C, and the temperature of the rear section is 50-55°C. Finally, it is mixed once through the dehumidification pipeline and discharged from the workshop, resulting in a large amount of heat waste. Therefore, the utility model provides a microwave drying device. Utility Model Content

[0005] In view of the deficiencies in the prior art, the utility model provides a microwave drying device to solve the problems raised by the above background technology.

[0006] To achieve the above objectives, the utility model is implemented through the following technical solutions: a microwave drying device, comprising a tunnel-type microwave drying machine and a material conveyor belt arranged on the tunnel-type microwave drying machine, wherein the upper end of the tunnel-type microwave drying machine is sequentially provided with two first microwave drying chambers and three second microwave drying chambers from the feeding end to the discharging end;

[0007] An air inlet communicating with the interior of the first microwave drying chamber is also provided at the upper end of the tunnel type microwave drying machine adjacent to the front side of one of the first microwave drying chambers;

[0008] The tops of the two first microwave drying chambers are both provided with low-temperature air outlets, and the low-temperature air outlets are provided with low-temperature air outlet pipes, and the other ends of the two low-temperature air outlet pipes are commonly connected with an external exhaust pipe;

[0009] The tops of the three second microwave drying chambers are all provided with high-temperature air outlets, and the high-temperature air outlets are connected to high-temperature air outlet pipes. The other ends of the three high-temperature air outlet pipes are commonly connected to a high-temperature return air pipe, and one end of the high-temperature return air pipe is connected to a circulating fan.

[0010] As a further technical solution of the utility model, the other end of the air inlet is connected to a high-temperature air inlet pipe, the other end of the high-temperature air inlet pipe is connected to the output end of the circulation fan, and the high-temperature return air pipe is connected to the input end of the circulation fan.

[0011] As a further technical solution of the utility model, the high-temperature air inlet pipe and the external air exhaust pipe are connected through a branch pipe, and an air volume regulating valve is installed on the branch pipe.

[0012] As a further technical solution of the utility model, one end of the external exhaust duct is connected to the interiors of the two first microwave drying chambers through a low-temperature air outlet pipe and a low-temperature air outlet, and the other end of the external exhaust duct is connected to an external exhaust fan.

[0013] As a further technical solution of the utility model, one end of the high-temperature return air duct is respectively connected to the interiors of the three second microwave drying chambers through a high-temperature outlet pipe and a high-temperature outlet.

[0014] The utility model provides a microwave drying device, which has the following beneficial effects compared with the prior art:

[0015] A microwave drying device of this design is equipped with a hot air circulation system at the high-temperature air outlet and the feed inlet of the microwave drying chamber. The high-temperature and dry air can be reused through the fan and the air volume regulating valve to achieve the purpose of energy saving. The single microwave heating mode is changed to a dual heating mode of microwave and hot air circulation, which makes the material drying more thorough, and can increase the speed of the microwave conveyor belt, thereby improving production efficiency and reducing product unit consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of a microwave drying device.

[0017] In the figure: 1. Tunnel type microwave dryer; 2. Low temperature air outlet; 21. Low temperature air outlet duct; 3. High temperature air outlet; 31. High temperature air outlet duct; 4. Air inlet; 41. High temperature air inlet duct; 5. High temperature return air duct; 6. External exhaust air duct; 7. Air volume regulating valve; 8. Circulating fan; 9. External exhaust fan; 10. Material conveyor belt; 11. First microwave drying chamber; 12. Second microwave drying chamber. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0019] See also Figure 1 The utility model provides a technical solution of a microwave drying device: a microwave drying device, comprising a tunnel-type microwave drying machine 1 and a material conveyor belt 10 arranged on the tunnel-type microwave drying machine 1, two first microwave drying chambers 11 and three second microwave drying chambers 12 are sequentially arranged at the upper end of the tunnel-type microwave drying machine 1 from the feeding end to the discharging end, the tops of the three second microwave drying chambers 12 are all provided with a high-temperature air outlet 3, and the high-temperature air outlet 3 is connected to a high-temperature air outlet pipe 31, the other ends of the three high-temperature air outlet pipes 31 are commonly connected to a high-temperature return air pipe 5, and one end of the high-temperature return air pipe 5 is connected to a circulation The circulating fan 8 and one end of the high-temperature return air duct 5 are respectively connected to the interiors of the three second microwave drying chambers 12 through the high-temperature air outlet duct 31 and the high-temperature air outlet 3. After the material is dried in the two first microwave drying chambers 11, when it is dried in the three second microwave drying chambers 12 in the rear section, the hot air in the three second microwave drying chambers 12 has high temperature and low humidity. Therefore, the circulating fan 8 is used in conjunction with the high-temperature return air duct 5 to recover the high-temperature hot air in the three second microwave drying chambers 12 from the high-temperature air outlet 3 and gather it into the high-temperature return air duct 5, and then transport it to the high-temperature air inlet duct 41 through the circulating fan 8.

[0020] An air inlet 4 connected to the interior of the first microwave drying chamber 11 is provided at the upper end of the tunnel-type microwave drying machine 1 near the front side of one of the first microwave drying chambers 11. The other end of the air inlet 4 is connected to a high-temperature air inlet pipe 41. The other end of the high-temperature air inlet pipe 41 is connected to the output end of the circulating fan 8. The high-temperature return air pipe 5 is connected to the input end of the circulating fan 8. When the high-temperature hot air in the three second microwave drying chambers 12 circulates into the high-temperature air inlet pipe 41 and then enters the first microwave drying chamber 11 through the air inlet 4, a hot air circulation system is formed, and the waste heat of the high-temperature hot air is used to heat the material.

[0021] The tops of the two first microwave drying chambers 11 are both provided with low-temperature air outlets 2, and low-temperature air outlet pipes 21 are provided on the low-temperature air outlets 2. The other ends of the two low-temperature air outlet pipes 21 are commonly connected with an external exhaust pipe 6. One end of the external exhaust pipe 6 is respectively connected with the insides of the two first microwave drying chambers 11 through the low-temperature air outlet pipe 21 and the low-temperature air outlet 2, and the other end of the external exhaust pipe 6 is connected with an external exhaust fan 9. After the temperature of the high-temperature hot air entering the first microwave drying chamber 11 for heating the material is reduced, it is discharged from the low-temperature air outlet 2. By using the cooperation of the external exhaust fan 9 and the low-temperature air outlet pipe 21, it can be discharged from the first microwave drying chamber 11;

[0022] The high-temperature air inlet pipe 41 is connected to the external exhaust pipe 6 through a branch pipe, and an air volume regulating valve 7 is installed on the branch pipe. By adjusting the air volume regulating valve 7, the amount of secondary air in the high-temperature return air pipe 5 can be controlled. At the same time, the rotation speed of the air volume regulating valve 7 and the circulating fan 8 can be controlled to make the secondary air use with maximum efficiency, thereby achieving the purpose of reducing microwave energy consumption.

[0023] The working principle of the utility model is as follows: first confirm the temperature and humidity of each air outlet of the tunnel type microwave dryer 1, and during use, transfer the centrifuged mannitol to the first microwave drying chamber 11 through the material conveyor belt 10, and use the two first microwave drying chambers 11 of the tunnel type microwave dryer 1 to perform microwave heating on the material. At this time, the temperature in the two first microwave drying chambers 11 is low and the humidity is high, and the low-temperature air inside the two first microwave drying chambers 11 will be discharged through the low-temperature air outlet 2 at the top thereof, and the low-temperature air will be discharged through the low-temperature air outlet pipe 21 and the external exhaust pipe 6 connected to the external exhaust fan 9;

[0024] When the material is transported to the second microwave drying chamber 12, the material is pre-heated by the two first microwave drying chambers 11. At this time, the air in the second microwave drying chamber 12 is of high temperature and low humidity. The high-temperature air at this time is transported from the high-temperature air outlet 3 to the high-temperature return air duct 5 to the high-temperature air inlet duct 41 in cooperation with the circulating fan 8, and then enters the first microwave drying chamber 11 through the air inlet 4. The material is heated by the waste heat of the high-temperature hot air, so that the material can be pre-heated and dried, and the high-temperature hot air in the second microwave drying chamber 12 can be recycled and reused, thereby achieving the purpose of energy saving.

[0025] Moreover, the rotation speed of the air volume regulating valve 7 and the circulating fan 8 is controlled so that the secondary air can be utilized with maximum efficiency, thereby achieving the purpose of reducing microwave energy consumption. It should be added that during the operation of the entire system, the rotation speed of the microwave conveyor belt is appropriately adjusted according to the moisture content of the finished product.

[0026] The above is only a preferred embodiment of the present invention. It should be noted that, for ordinary technicians in the technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. A microwave drying device, characterized in that: The invention comprises a tunnel-type microwave drying machine (1) and a material conveyor belt (10) arranged on the tunnel-type microwave drying machine (1), wherein two first microwave drying chambers (11) and three second microwave drying chambers (12) are sequentially arranged at the upper end of the tunnel-type microwave drying machine (1) from the feeding end to the discharging end; An air inlet (4) communicating with the interior of the first microwave drying chamber (11) is also provided at the upper end of the tunnel-type microwave drying machine (1) and adjacent to the front side of one of the first microwave drying chambers (11); The tops of the two first microwave drying chambers (11) are both provided with low-temperature air outlets (2), and the low-temperature air outlets (2) are provided with low-temperature air outlet pipes (21), and the other ends of the two low-temperature air outlet pipes (21) are commonly connected to an external exhaust pipe (6); The tops of the three second microwave drying chambers (12) are all provided with high-temperature air outlets (3), and the high-temperature air outlets (3) are connected to high-temperature air outlet pipes (31), and the other ends of the three high-temperature air outlet pipes (31) are commonly connected to a high-temperature return air pipe (5), and one end of the high-temperature return air pipe (5) is connected to a circulating fan (8).

2. A microwave drying device according to claim 1, characterized in that: The other end of the air inlet (4) is connected to a high-temperature air inlet pipe (41), the other end of the high-temperature air inlet pipe (41) is connected to the output end of the circulation fan (8), and the high-temperature return air pipe (5) is connected to the input end of the circulation fan (8).

3. A microwave drying device according to claim 2, characterized in that: The high-temperature air inlet pipe (41) and the external air exhaust pipe (6) are connected via a branch pipe, and an air volume regulating valve (7) is installed on the branch pipe.

4. A microwave drying device according to claim 1, characterized in that: One end of the external exhaust duct (6) is respectively connected to the interior of the two first microwave drying chambers (11) through a low-temperature air outlet duct (21) and a low-temperature air outlet (2), and the other end of the external exhaust duct (6) is connected to an external exhaust fan (9).

5. A microwave drying device according to claim 1, characterized in that: One end of the high-temperature return air duct (5) is respectively connected to the interior of the three second microwave drying chambers (12) through a high-temperature outlet duct (31) and a high-temperature outlet (3).

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