A drying device

Abstract

This utility model relates to the field of drying equipment technology, and in particular to a drying device, comprising a vertical drying area surrounded by drying components. The drying area can simultaneously dry at least one pair of sides of the components to be dried. The drying area has at least one inlet and one outlet for the components to be dried. It also includes a traction mechanism that pulls the components to be dried vertically through the drying area from the inlet and out from the outlet. The drying channel is arranged vertically, with guide rollers and traction rollers positioned at the uppermost and lowermost ends, respectively. The components to be dried pass vertically through the drying area. The drying area dries the components from both sides, completely avoiding physical contact with the guide rollers and traction rollers during the drying process to prevent process defects such as printing transfer, blurring, misalignment, and deformation. This reduces the drift amplitude of the components to be dried, achieving uniform drying on both sides and controlling the migration of the components to be dried.

Description

Technical Field

[0001] This utility model relates to the field of drying technology, and in particular to a drying device. Background Technology

[0002] Dyeing and drying is one of the core processes in textile dyeing and printing. It involves removing moisture and fixing dyes / sizing agents through physical means after dyeing and printing, directly affecting the fabric's colorfastness, hand feel, dimensional stability, and finished product quality. This technology is widely used in the processing of cotton, linen, silk, chemical fibers, and their blends, covering clothing fabrics, home textiles, and industrial textiles.

[0003] Contact drying (drying cylinder drying): The fabric is directly exposed to a high-temperature drying cylinder (steam-heated or electrically heated, temperature 80-200℃), and moisture is evaporated through heat conduction.

[0004] Advantages: Fast drying speed (linear speed up to 30-60 meters / minute), suitable for heavy fabrics (such as denim and canvas), and can simultaneously smooth the fabric surface.

[0005] Defects: High-temperature contact can easily cause chemical fiber fabrics to melt and turn yellow (e.g., polyester has a temperature resistance of ≤130℃), and natural fibers to become brittle (e.g., cotton fibers are prone to oxidation when exposed to high temperatures for a long time); uneven surface temperature of the drying cylinder (temperature difference of ±5℃ or more) or fluctuations in fabric tension can easily lead to local over-drying or under-drying, resulting in color spots and wrinkles; the equipment occupies a large area, and the pressure and temperature of the drying cylinder need to be frequently adjusted when changing production models, resulting in low flexibility.

[0006] In non-contact drying (hot air / infrared / microwave):

[0007] Hot air drying: This method utilizes circulating hot air (60-150℃) for convective heat exchange, and achieves fabric suspension drying through mesh belt, air cushion, or tenter frame machines. It is suitable for most conventional fabrics. However, it suffers from problems such as low thermal efficiency (hot air heat energy utilization rate is only 30%-40%), high energy consumption (1.5-2.5 tons of steam per ton of fabric), and large exhaust emissions.

[0008] Infrared drying: This method directly heats the fabric's moisture using infrared radiation (medium-wave / short-wave infrared), resulting in rapid heating (reaching the target temperature within 5-10 seconds). It is suitable for thin fabrics (such as finely printed fabrics and silk). However, infrared penetration depth is limited (only 0.5-2mm), requiring multiple layers for drying thick fabrics, which can easily lead to uneven moisture content between the surface and the interior.

[0009] Microwave drying: Utilizes microwaves (2450MHz or 915MHz) to cause water molecules to vibrate at high frequency and generate heat. It has advantages such as uniform heating, energy saving (30% lower energy consumption than hot air), and fast speed (reducing moisture content from 80% to 10% in just 2-3 minutes). However, the equipment cost is high (3-5 times that of hot air equipment), and uneven microwave field distribution can easily lead to localized overheating. It also places strict requirements on fabric size and equipment sealing.

[0010] Moreover, the temperature and wind speed fields of traditional equipment are unevenly distributed (such as blockage of the air duct of the hot air dryer and scale on the surface of the drying cylinder), resulting in a difference of ≥5% in the moisture content of the fabric in the transverse direction (edge ​​and center) and a fluctuation of ≥1 grade in the color fastness in the longitudinal direction (front and back sections) (according to ISO 105 standard).

[0011] In fabrics with high moisture content, dye molecules are easily diffused with the moisture. If reactive dyes are heated too quickly in the early stage of high-temperature drying (when the moisture content is >50%), it can easily lead to color spots, and the defect rate can reach 10%-15%.

[0012] The exhaust gas temperature of hot air drying equipment can reach 80-120℃. Direct emission results in a large waste of sensible heat, and the VOCs in the exhaust gas need to be treated by activated carbon adsorption or incineration, which increases costs.

[0013] Drying cylinders rely on high-pressure steam (0.5-1.0MPa), and the heat loss of the steam pipeline network reaches 15%-20%, resulting in low overall energy utilization. Utility Model Content

[0014] The purpose of this invention is to overcome the defects in the existing technology and provide a drying device.

[0015] To achieve the above objectives, the technical solution of this utility model is to design a drying device, including a vertical drying area surrounded by drying components, wherein the drying area can simultaneously dry at least a pair of sides of the components to be dried, and the drying area has at least one inlet and one outlet for the components to be dried.

[0016] It also includes a traction mechanism that pulls the part to be dried vertically through the drying area from the inlet and out from the outlet.

[0017] In a further preferred embodiment, the drying zone comprises one or any combination of two or more of the following: a hot air drying zone, an infrared drying zone, and a microwave drying zone.

[0018] In a further preferred embodiment, the drying zone is composed of multiple zones with different temperatures.

[0019] In a further preferred embodiment, the drying zone may consist of one or more symmetrically arranged drying components.

[0020] In a further preferred embodiment, the drying component is one or a combination of two or more of the following: a hot air box, an infrared heating tube, and a microwave tube.

[0021] A further preferred technical solution also includes a drying waste gas recovery mechanism, which is located at the end of the drying area to collect the drying waste gas.

[0022] In a further preferred embodiment, the drying exhaust gas recovery mechanism includes at least a pair of symmetrically arranged suction fans, which are connected to a heat exchanger via pipes, and each pipe is equipped with a regulating valve.

[0023] In a further preferred embodiment, the heat exchanger is connected to the air inlet of a hot air circulating fan via a pipe, the air outlet of the hot air circulating fan is connected to a steam heater, the steam heater is equipped with a high-temperature steam inlet pipe, the steam inlet pipe is equipped with a steam regulating valve, the steam heater is connected to a hot air box via corresponding pipes, and a wind speed regulating valve is provided on the pipe between the steam heater and the hot air box.

[0024] In a further preferred embodiment, the drying area is equipped with one or any combination of two or more of the following: a temperature sensor, a pressure sensor, and a wind speed sensor.

[0025] In a further preferred embodiment, the traction mechanism includes at least a guide roller disposed outside the inlet and the outlet.

[0026] The advantages and beneficial effects of this utility model are as follows: 1. The drying channel is arranged vertically, with the guide roller and traction roller arranged at the top and bottom ends respectively. The workpiece to be dried passes vertically through the drying area. The drying area dries the workpiece on both sides. Physical contact with the guide roller and traction roller is completely avoided during the drying process to prevent process defects such as printing transfer, blurring, misalignment and deformation. The drift amplitude of the workpiece to be dried is reduced. The workpiece is dried evenly on both sides through the drying area, and the migration of the workpiece to be dried is controlled.

[0027] 2. Several static pressure boxes are arranged in sequence on both sides of the drying channel to form a pressure field of 0.8-1.2 kPa in the air duct; the contact pressure between the fabric surface and the airflow layer is monitored in real time by a pressure sensor, and the wind speed at the outlet of the static pressure box is monitored in real time by an anemometer, and the air pressure and wind speed are corrected in real time.

[0028] 3. The waste heat recovery device uses a shell-and-tube heat exchanger to heat the fresh air, making full use of waste heat. The humid and hot air discharged from the drying room is preheated by the heat exchanger (temperature rise of 20-25℃), and the overall energy saving rate can reach more than 30%.

[0029] 4. Improve automation by using PLC for effective and precise control, thereby increasing work efficiency and product qualification rate. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the present invention;

[0031] Figure 2 This is a schematic diagram of a specific embodiment of the present utility model;

[0032] In the diagram: 10. Drying area; 11. Outer outlet; 12. Inlet;

[0033] 20. Drying components; 21. Vertical chamber; 22. Waste gas recovery mechanism; 23. Hot air box; 24. Temperature sensor; 25. Pressure sensor; 26. Wind speed sensor; 27. Air volume regulating valve;

[0034] 30. Traction mechanism; 31. Guide roller; 32. Traction roller;

[0035] 40. Parts to be dried;

[0036] 50. Steam heater; 51. Steam inlet pipe; 52. Steam regulating valve; 60. Hot air circulating fan; 70. Heat exchanger. Detailed Implementation

[0037] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0038] Reference Figure 1 As shown, a drying device includes a vertical drying area 10 surrounded by drying elements 20. The drying area 10 can simultaneously dry at least a pair of sides of the element 40 to be dried. The drying area 10 has at least an inlet 12 and an outlet 11 for the element 40 to be dried. It also includes a traction mechanism 30, which tractions the element 40 to be dried vertically through the inlet 12 through the drying area 10 and out through the outlet 11.

[0039] The part to be dried 40 can be a fabric or textile such as cotton, linen, silk, chemical fiber and its blends. After dyeing, printing and other treatments are completed, the part to be dried 40 is dried to remove moisture and fix the dye / paste. The part to be dried 40 passes vertically through the drying area 10. The drying area 10 dries the part to be dried 40 from both sides. Physical contact with the guide roller and traction roller is completely avoided in the drying process to prevent process defects such as printing transfer, blurring, misalignment and deformation. The drift amplitude of the part to be dried 40 is reduced. The part to be dried 40 is dried evenly on both sides through the drying area 10, and the migration of the part to be dried 40 is controlled.

[0040] When drying elastic fabrics (such as spandex blends), if the traction force on the front and back sides is inconsistent (deviation > 5N), it can easily lead to weft skew (> 3%) or wrinkling of the fabric surface. The weft skew rate of traditional guide roller drying is 12%. When drying double-sided printed and dyed products, the risk of weft skew increases to more than 20% due to the difference in the moisture absorption rate of the dyes on the two sides. However, the risk of weft skew can be significantly reduced by using the vertical traction mechanism 30.

[0041] The drying component 20 can be one or a combination of two or more of the following: hot air box 23, infrared heating tube, and microwave tube.

[0042] The hot air box 23 uses hot air drying, utilizing circulating hot air (60-150℃) for convective heat exchange, and achieves fabric suspension drying through a mesh belt, air cushion, or tenter frame.

[0043] Infrared drying using infrared heating tubes: The fabric moisture is directly heated by infrared radiation (medium wave / short wave infrared), and the temperature rises quickly, reaching the target temperature within 5-10 seconds. It is suitable for drying thin fabrics, such as printed fine fabrics and silk.

[0044] Microwave drying using microwave tubes: Utilizing microwaves (2450MHz or 915MHz) to cause water molecules to vibrate at high frequency and generate heat, it features uniform heating, energy saving (energy consumption is 30% lower than that of hot air), and fast speed. The moisture content can be reduced from 80% to 10% in just 2-3 minutes.

[0045] The drying area 10 can be composed of one or more symmetrically arranged drying elements 20. Specifically, according to the drying requirements of the item 40 to be dried, the drying area 10 can be composed of one symmetrically arranged drying elements 20. When one set of drying elements 20 cannot meet the drying requirements, a second set of drying elements 20 can be added in the vertical direction. The second set of drying elements 20 is stacked on top of the first set of drying elements 20 in the vertical direction. Similarly, a third set of drying elements 20 and a fourth set of drying elements 20 can be added in the vertical direction to form the drying area 10, so as to meet the drying requirements of different items 40 to be dried.

[0046] The drying zone 10 consists of one or any combination of two or more of the following: a hot air drying zone, an infrared drying zone, and a microwave drying zone. Specifically, it combines infrared and hot air drying. The infrared drying zone consists of a pair of infrared heating tubes, and the hot air drying zone consists of a pair of hot air boxes. The infrared drying zone can quickly dehydrate the surface of the part to be dried, while the hot air drying zone can allow the internal moisture of the part to migrate. For example, the infrared pre-drying at the front removes 60% of the surface moisture, and the hot air penetration drying at the back can control the moisture content difference within ±2%.

[0047] It also includes a drying exhaust gas recovery mechanism 22, which is located at the end of the drying area 10 to collect the drying exhaust gas. During the drying process, the energy consumption of the drying process accounts for 30%-50% of the total energy consumption of printing and dyeing. Traditional hot air drying equipment relies on steam or electric heating, with a thermal efficiency of only 40%-60%. Moreover, the exhaust gas often contains volatile organic compounds (VOCs, such as dye solvents and sizing agents) and dust. The drying exhaust gas recovery mechanism 22 can collect the exhaust gas and dust.

[0048] Specifically, the drying exhaust gas recovery mechanism 22 includes at least a pair of symmetrically arranged suction fans. The suction fans collect the exhaust gas generated during the drying process through negative pressure and connect it to an external exhaust gas treatment device through a pipeline. Since the exhaust gas is generated during the drying process, it contains a large amount of heat energy. In order to reduce the drying energy consumption, the drying exhaust gas recovery mechanism 22 is connected to the heat exchanger 70 through a pipeline. In particular, when the drying component uses the hot air box, the hot air box 23 heats the air through the steam heater 50 and then blows it into the drying area 10 to dry the component 40. Therefore, the high-temperature exhaust gas can be introduced into the heat exchanger 70 through a pipeline, and the air can also be introduced into the heat exchanger 70 to exchange heat with the high-temperature exhaust gas, thereby increasing the air temperature, reducing the energy consumption required to heat the air, and reducing the energy consumption of the drying device.

[0049] Integrating plate heat exchangers or rotary heat recovery devices into hot air equipment can preheat fresh air by using the heat from exhaust gas, which can reduce energy consumption by 20%-30%. Moreover, using heat pump-type low-temperature drying (50-80℃) and utilizing the reverse Carnot cycle to achieve heat transfer can save more than 50% of energy compared to traditional electric heating, making it suitable for heat-sensitive fabrics such as wool and silk.

[0050] During the drying process, a near-infrared moisture content sensor (accuracy ±1%) and a thermal imager (temperature resolution ±1℃) are installed in the drying area 10 to collect data in real time. The drying parameters are self-optimized through a PLC or industrial internet platform, and the defect rate can be reduced to below 5%.

[0051] When the drying component 20 uses a hot air box 23, a pressure sensor 25, a wind speed sensor 26 and a pneumatic valve are installed in the drying area 10. The wind speed in each area is dynamically adjusted by the pressure sensor, the wind speed sensor 26 and the pneumatic valve with an accuracy of ±0.5m / s to compensate for the tension fluctuations of the component 40 to be dried during operation.

[0052] Because the double-sided fixation of reactive dyes requires precise control at 160-180℃ (±5℃), insufficient temperature will result in residual hydrolyzed dyes and decreased color fastness, while excessive temperature will cause cellulose oxidation, resulting in a strength loss of ≥10%. The disperse dyes used in digital printing need to be controlled at 185-210℃. Temperature fluctuations exceeding ±3℃ will result in color shift (ΔE*ab≥1.0). The dye fixing temperature window is narrow. Therefore, the drying zone 10 is composed of multiple zones with different temperatures for precise temperature control. The drying zone 10 includes at least a preheating zone at 120℃, a fixing zone at 160-180℃, and a cooling zone at <60℃. The drying zone is divided into three sections: preheating zone (120℃), fixing zone (160-180℃), and cooling zone (<60℃). Each zone is equipped with an independent temperature control module (accuracy ±1℃) and an integrated infrared thermometer (response time <0.5s) for real-time feedback and adjustment. This can solve the problem of the narrow dye fixing temperature window. Each zone can be composed of a set of symmetrically arranged drying components 20. The drying components 20 can be one or a combination of two or more of the following: hot air box 23, infrared heating tube, and microwave tube.

[0053] Moreover, during high-speed production (>50m / min), the traditional PID temperature control system has a lag in response (delay time >8s), resulting in a temperature deviation of more than 10℃ between the front and rear fabric surfaces, causing "color difference between the beginning and end". The fabric running speed and temperature are coupled together. By controlling the drying temperature through an independent temperature control module and establishing a three-dimensional model of temperature-vehicle speed-dye concentration through machine learning, the adjustment amount of temperature control parameters can be predicted 30m in advance, so that the temperature fluctuation is controlled within ±2℃ and the color stability is improved to ΔE*ab≤0.8.

[0054] In order to introduce the workpiece 40 to be dried into the drying area 10 and completely avoid physical contact with the guide roller and traction roller during the drying process, the traction mechanism 30 includes at least a guide roller located outside the inlet 12 and the outlet 11. The workpiece 40 is pulled through the drying area 10 by the guide roller. The walking power of the entire workpiece 40 can be traction by the stenter. The drying device has no speed control or traction power.

[0055] In other embodiments, the traction mechanism 30 may also include a drive mechanism with traction power, such as a traction roller driven by a drive motor, which may be externally positioned downstream along the traction direction to traction the workpiece 40 to be dried and to adjust the speed of the workpiece 40 to be dried.

[0056] The traction mechanism 30 can also be a linear lifting mechanism. A linear lifting mechanism is a mechanical device that enables the vertical or inclined displacement of a heavy object. It can convert rotational motion into precise linear lifting motion through mechanical transmission. The cooperation between the ball screw, synchronous belt or synchronous chain and the drive motor will not be described in detail here.

[0057] In one specific implementation, refer to Figure 2 As shown, taking the drying component 20 using a hot air box 23 as an example, two sets of static pressure uniform speed hot air boxes 23 are provided in a vertical drying area 10. One set consists of two symmetrically arranged static pressure uniform speed hot air boxes 23. The two sets of static pressure uniform speed hot air boxes 23 are stacked vertically to form the drying area 10. In order to improve the drying effect and reduce energy efficiency, the drying area 10 can be formed by a vertical box body 21 to form a closed drying channel. Each set of static pressure uniform speed hot air boxes 23 is symmetrically installed on the vertical box body 21. The vertical drying area 10 surrounded by the symmetrically arranged hot air boxes 23 arranges the drying channel vertically. At the uppermost and lowermost ends of the drying channel, guide rollers 31 and traction rollers 32 are respectively provided, so that the component 40 to be dried is guided into the vertical drying area 10 by the traction roller 32 at the lower end and passes vertically through the drying area 10 and is led out by the guide roller 31. Hot air is evenly and finely blown into the box body through the hot air box 32 to dry the component 40 on both sides.

[0058] Each of the hot air boxes 32 is connected to the outlet of a steam heater 50 via a corresponding pipe. The steam heater 50 is equipped with a high-temperature steam inlet pipe 51 and a steam regulating valve 52. The air inlet of the steam heater 50 is connected to the air outlet of the hot air circulating fan 60. Each pipe is also equipped with an airflow regulating valve 27 to control the airflow speed. Wind speed sensors 26 are also installed between a group of hot air boxes 23 and near the outlet of each hot air box. The wind speed sensors 26 monitor the preset airflow speed of the workpiece 40 to be dried in real time and record the actual airflow speed. Feedback is sent to the control unit, which adjusts the air intake volume via the air volume regulating valve 27 to control the wind speed. A double-sided blowing hot air box 23 is used, and the blowing volume is adjusted in real time via the wind speed sensor 26 (error ≤ ±5%) to keep the air volume error between the front and back sides of the item to be dried 40 within 5% and the temperature difference within ±3℃. In addition, the drying area 10 uses a two-sided blowing static air box 23 to make the wind speed uniform and stable, and the wind speed is low, reducing the amplitude of the item to be dried 40 fluttering. This avoids the problem that thin fabrics (such as chiffon below 100g / m²) are easily caused to flutter by high-speed hot air (wind speed > 15m / s), which causes the fabric surface to rub against the guide roller and produce aurora marks (occurrence rate of about 8%), affecting the consistency of the appearance of both sides.

[0059] By having the item to be dried 40 pass vertically through the drying area 10, a tension-free hanging drying process is formed, which avoids the problem of unbalanced stress on both sides. In particular, when drying elastic fabrics (such as spandex blended fabrics), if the traction force on the front and back sides is inconsistent (deviation > 5N), the problem of weft skew (> 3%) or fabric wrinkling is significantly reduced.

[0060] Pressure sensors 25 are also installed between a group of hot air boxes 23 and near the outlet of the hot air box 30 to form a pressure field of 0.8-1.2 kPa in the air duct. The pressure sensors 25 monitor the contact pressure between the surface of the workpiece 40 to be dried and the airflow layer in real time, and the wind speed sensor 26 monitors the wind speed at the outlet of the hot air box 23 in real time, and corrects the wind pressure and wind speed in real time.

[0061] Temperature sensors 24 are installed between a set of hot air boxes 23 and near the outlet of the hot air box 23. The temperature sensors 24 monitor the preset temperature of the workpiece 40 to be dried in real time and feed the actual temperature back to the control unit. The control unit then adjusts and controls the temperature through the steam regulating valve 52 of the steam heater 50, keeping the temperature difference within ±3℃. Furthermore, the drying area between the two sets of hot air boxes 23 can be precisely temperature-controlled by partitioning: the drying area is divided into a preheating zone (120℃) and a color-fixing zone (160-180℃), each equipped with an independent temperature sensor (accuracy ±1℃). An infrared thermometer (response time <0.5s) can also be integrated for real-time feedback adjustment. Double-sided color fixing of reactive dyes requires precise control at 160-180℃ (±5℃). A three-dimensional model of temperature-vehicle speed-dye concentration is established, and adjustments are made 30m in advance. The predicted temperature control parameter adjustment ensures that temperature fluctuations are kept within ±2℃, and the color stability is improved to ΔE*ab≤0.8. This avoids the problems of insufficient temperature leading to residual hydrolyzed dyes and decreased color fastness, and excessive temperature leading to cellulose oxidation (strength loss ≥10%).

[0062] A pair of suction boxes 22 are also provided on the vertical box 21 above the two sets of hot air boxes 20. The suction boxes 22 collect the exhaust gas generated during the drying process through negative pressure and connect it to the heat exchanger 70 through pipes. The heat exchanger 70 is connected to an external exhaust gas treatment device. Each pipe is also equipped with a wind speed regulating valve 27. Since the exhaust gas is generated during the drying process, it contains a large amount of heat energy. In order to reduce drying energy consumption, the suction boxes 22 are connected to the heat exchanger 70 through pipes. In particular, when the drying component 20 uses the hot air box 23, the hot air box 23 uses steam. Heater 50 heats the air and then blows it into drying zone 10 through hot air box 23 to dry the workpiece 40. Therefore, high-temperature exhaust gas can be introduced into heat exchanger 70 through pipes, and air can also be introduced into heat exchanger 70 to exchange heat with the high-temperature exhaust gas, thereby increasing the air temperature and reducing the energy consumption required to heat the air. The heated air is connected to the air inlet of hot air circulation fan 60 through pipes, and then enters steam heater 50 from the air outlet of hot air circulation fan 60. The exhaust gas temperature of hot air drying equipment is as high as 80-120℃. Direct discharge will cause a large amount of sensible heat to be wasted, and the VOCs in the exhaust gas need to be treated by activated carbon adsorption or incineration, which increases costs. By preheating the fresh air (temperature rise of 20-25℃) of the humid hot air discharged during the drying process through heat exchanger, the comprehensive energy saving rate can reach more than 30%, which reduces the energy consumption of the drying device. Moreover, drying relies on high-pressure steam (0.5-1.0MPa), and the heat loss of steam pipeline reaches 15%-20%, resulting in low comprehensive energy utilization.

[0063] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A drying apparatus, characterized in that, It includes a vertical drying area surrounded by drying components, the drying area being capable of simultaneously drying at least a pair of sides of the components to be dried, and the drying area having at least one inlet and one outlet for the components to be dried; It also includes a traction mechanism that pulls the part to be dried vertically through the drying area from the inlet and out from the outlet.

2. The drying apparatus according to claim 1, characterized in that, The drying zone consists of one or any combination of two or more of the following: a hot air drying zone, an infrared drying zone, and a microwave drying zone.

3. The drying apparatus according to claim 1, characterized in that, The drying zone is composed of multiple zones with different temperatures.

4. The drying apparatus according to claim 1, characterized in that, The drying zone can consist of one or more symmetrically arranged drying elements.

5. A drying apparatus according to any one of claims 1-4, characterized in that, The drying component is one or a combination of two or more of the following: a hot air box, an infrared heating tube, and a microwave tube.

6. A drying apparatus according to claim 5, characterized in that, It also includes a drying exhaust gas recovery mechanism, which is located at the end of the drying area to collect the drying exhaust gas.

7. A drying apparatus according to claim 6, characterized in that, The drying exhaust gas recovery mechanism includes at least a pair of symmetrically arranged suction fans, which are connected to a heat exchanger through pipes, and each pipe is equipped with a regulating valve.

8. A drying apparatus according to claim 7, characterized in that, The heat exchanger is connected to the air inlet of the hot air circulating fan via a pipe. The air outlet of the hot air circulating fan is connected to the steam heater. The steam heater is equipped with a high-temperature steam inlet pipe and a steam regulating valve. The steam heater is connected to the hot air box via corresponding pipes. A wind speed regulating valve is installed on the pipe between the steam heater and the hot air box.

9. A drying apparatus according to claim 8, characterized in that, The drying area is equipped with one or any combination of two or more of the following: temperature sensor, pressure sensor, and wind speed sensor.

10. A drying apparatus according to claim 1, characterized in that, The traction mechanism includes at least a guide roller disposed outside the inlet and outlet.

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