A cold air drying device based on variable temperature and continuous drying and its application

Abstract

The present invention provides a cold air drying device based on variable temperature and continuous drying and its application. The cold air drying device includes a drying box and a cold air device. The drying box includes a drying box body. At least two air inlets and return air ports corresponding to each air inlet are provided along the feed end to the discharge end of the drying box body, and a material conveying device is provided between the feed end and the discharge end of the drying box body. The cold air device is connected to each air inlet, and is used to provide dry cold air to the air inlet on the drying box body, so that the dry cold air temperature of the air inlet close to the feed end of the drying box body is lower than the dry cold air temperature of the air inlet far from the feed end, and the dry cold air temperature of the air inlet closest to the discharge end is ±5°C of the ambient temperature outside the drying box. The cold air drying device of the present invention is particularly suitable for drying temperature-sensitive materials, and can avoid the problem of moisture resorption of the dried materials during the process of outputting the dried materials from the drying box.

Description

Technical Field

[0001] The invention belongs to the field of biomedical engineering and relates to a drying device design technology, in particular to a cold air drying device based on variable temperature and continuous drying and an application thereof. Background Art

[0002] Cold air drying uses low-temperature dry air to act on objects, gradually reducing the water content in the objects and achieving the purpose of drying. It is widely used in the drying processing of agricultural and forestry by-products, Chinese medicinal materials, additives, health care products and other products.

[0003] At present, most cold air drying equipment is a box-type structure. After one batch of materials is dried and taken out, the next batch of materials can be dried, which greatly affects the working efficiency of the material drying production line. At the same time, the low-temperature dry air in each part of the box of the cold air drying equipment is uniform, the drying cycle of a batch of materials is long, and the problem of condensation and moisture return is easy to occur in the process of taking out the materials after drying. Summary of the invention

[0004] The purpose of the present invention is to solve the problems of low production line efficiency, long drying cycle for the same batch of materials and easy condensation of water vapor and moisture return of materials in existing cold air drying equipment, and to provide a cold air drying equipment based on variable temperature and continuous drying and its application.

[0005] The technical solution to achieve the purpose of the invention is as follows:

[0006] In a first aspect, the present invention provides a cold air drying device based on variable temperature and continuous drying, comprising a drying box and a cold air device.

[0007] The drying box includes a drying box body, at least two air inlets and return air outlets corresponding to each air inlet are provided along the drying box body from the feed end to the discharge end, and a material conveying device is provided between the feed end and the discharge end of the drying box body.

[0008] Among them, the cold air device is connected to each air inlet, and is used to provide dry cold air to the air inlet on the drying box body, so that the dry cold air temperature of the air inlet close to the feed end of the drying box body is lower than the dry cold air temperature of the air inlet far from the feed end, and the dry cold air temperature of the air inlet closest to the discharge end is ±5°C of the ambient temperature outside the drying box.

[0009] The cold air drying equipment designed by the present invention first designs a drying box, by providing at least two air inlets and return air outlets corresponding to each air inlet on the drying box body along the direction from the feed end to the discharge end, and at the same time providing a material conveying device between the feed end and the discharge end of the drying box body; secondly, the cold air device is connected to the air inlet to provide cold air of no matter the temperature to each air inlet, so that the dry cold air temperature of the air inlet close to the feed end is lower than the dry cold air temperature of the air inlet far from the feed end (that is, the dry cold air temperature of the air inlet along the feed end to the discharge end gradually increases).

[0010] When the cold air drying equipment is in operation, the temperature of the cold air that the material just enters the drying box body through the feed end is the lowest. As the material is transported from the feed end to the discharge end by the material conveying device, the material is continuously dried, and the temperature of the cold air that the material contacts gradually increases. Finally, the temperature of the dry cold air at the air inlet closest to the discharge end is ±5°C of the external ambient temperature of the drying box body, so that the temperature of the material when it is transported out of the drying box is close to the external ambient temperature, avoiding the phenomenon of moisture recurrence of the material.

[0011] Furthermore, the dry cold air temperature of the air inlet on the drying box body closest to the feed end ranges from 4 to 10°C, and the dry cold air temperature of the air inlet on the drying box body closest to the discharge end is ±2°C of the ambient temperature outside the drying box.

[0012] In one embodiment of the cold air structure of the present invention, the cold air device comprises a cold air structure, and the cold air structure is connected to the drying box body.

[0013] The cold air structure includes a cold air processor, the outlet end of the cold air processor is provided with a first cold air outlet main pipe, the first cold air outlet main pipe is provided with at least two cold air outlet branches, and the cold air outlet branches are connected to the air inlet. The air inlet end of the cold air processor is provided with a cold air inlet main pipe, the cold air inlet main pipe is provided with at least two cold air inlet branches, and the cold air inlet branches are connected to the return air port.

[0014] The cold air device also includes a heat exchange structure, which is used to exchange heat with the cold air in the first cold air outlet pipe, so that the temperature of the cold air in the first cold air outlet pipe gradually increases from the front end to the end of the first cold air outlet pipe.

[0015] Furthermore, the number of the cold air outlet branch pipes is ≥ the number of the air inlets, and the number of the cold air inlet branch pipes is ≥ the number of the return air outlets.

[0016] Preferably, in order to prevent the cold air from flowing back, a one-way valve is provided on each cold air outlet branch pipe and each cold air inlet branch pipe.

[0017] In one embodiment of the heat exchange structure of the present invention, the heat exchange structure comprises a heat exchange tube, which is wound around the outer wall of the first cold air outlet pipe. The air inlet end of the heat exchange tube is connected to the air outlet end of the heat exchanger, and the air outlet end is connected to the air inlet end of the heat exchanger, and the air inlet end of the heat exchange tube is located at the front end of the first cold air outlet pipe, and the air outlet end of the heat exchange tube is located at the end of the first cold air outlet pipe.

[0018] In one embodiment of the above-mentioned cold air drying device based on variable temperature and continuous drying of the present invention, the cold air drying device also includes a temperature control structure, and the temperature control structure is used to adjust the temperature of the dry cold air output from the drying box body through the air inlet.

[0019] Furthermore, the temperature control structure includes a first temperature compensation structure and a second temperature compensation structure. The first temperature compensation structure is connected to each cold air outlet branch pipe via a pipeline, and is used to cool down the dry cold air input to the drying box body. The second temperature compensation structure is a second cold air outlet main pipe connected to the cold air processor, and the second cold air outlet main pipe is connected to each cold air outlet branch pipe via a pipeline, and is used to heat up the dry cold air input to the drying box body.

[0020] In another embodiment of the above-mentioned cold air drying device based on variable temperature and continuous drying of the present invention, the cold air drying device also includes a cold air flow control structure, and the cold air flow control structure is used to make the pressure at all places in the drying box body the same.

[0021] The cold air flow control structure comprises flow valves respectively arranged on each cold air outlet branch pipe and each cold air inlet branch pipe, and also comprises a plurality of wind speed sensors and a plurality of air pressure sensors arranged in the drying box body.

[0022] In a second aspect, the present invention provides an application of a cold air drying device based on variable temperature and continuous drying, wherein the cold air drying device designed in the first aspect is used to perform cold air drying on temperature-sensitive materials.

[0023] Furthermore, the temperature-sensitive material includes biopolymer material.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: the cold air drying equipment designed by the present invention can realize the continuous input of materials to be dried and output of dried materials into the drying box through the design of the drying box and the cold air device, thereby improving the output efficiency of the drying equipment; on the other hand, the temperature of the cold air contacted by the materials that have just entered the drying box body through the feed end is the lowest. As the materials are transported from the feed end to the discharge end by the material conveying device, the materials are continuously dried, and the temperature of the cold air contacted by the materials gradually increases. Finally, the temperature of the dry cold air at the air inlet closest to the discharge end is ±5°C of the external ambient temperature of the drying box body, so that the temperature of the materials when they are transported out of the drying box is close to the external ambient temperature, thereby avoiding the phenomenon of moisture resorption of the materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only for the purpose of more clearly illustrating the technical solutions of the embodiments of the present invention or the prior art. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 It is a structural diagram of a cold air drying device based on variable temperature and continuous drying in a specific implementation manner;

[0027] Among them, 1. Drying box body; 2. Air inlet; 3. Return air outlet; 4. Material conveying device; 5. Cold air processor; 6. First cold air outlet pipe; 7. Cold air outlet branch pipe; 8. Cold air inlet pipe; 9. Heat exchange structure; 10. Heat exchange tube; 11. Heat exchanger; 12. First temperature compensation structure; 13. Second temperature compensation structure; 14. Flow valve. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with specific embodiments, and the advantages and features of the present invention will become clearer as the description proceeds. However, these embodiments are exemplary only and do not constitute any limitation to the scope of the present invention. It should be understood by those skilled in the art that the details and forms of the technical solution of the present invention may be modified or replaced without departing from the spirit and scope of the present invention, but these modifications and replacements all fall within the scope of protection of the present invention.

[0029] In the description of this embodiment, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the invention.

[0030] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0031] This specific embodiment provides a cold air drying device based on variable temperature and continuous drying. The cold air drying device includes a drying box and a cold air device. The drying box is used to dry materials. The cold air device is connected to the drying box and provides dry cold air for the drying box.

[0032] Among them, Figure 1 As shown, the drying box has a heat preservation function, including a drying box body 1, at least two air inlets 2 and return air ports 3 corresponding to each air inlet 2 are provided on the drying box body 1 from the feed end to the discharge end, and the positions of the air inlets 2 correspond to the positions of the return air ports 3. By designing the air inlets 2 and the return air ports 3 in the drying box body 1 to correspond to each other, the dry cold air can enter through the air inlet 2 to dry the material in the coverage range of the air inlet 2, and then be output from the return air ports 3 corresponding to the air inlet 2, so that multiple complementary and interfering temperature gradient zones are formed in the drying box body 1, and at the same time, in order to further avoid the cross-flow of dry cold air in adjacent temperature gradient zones. In this specific embodiment, the distances between adjacent air inlets 2 on the drying box body 1 can be the same or different.

[0033] Among them, a material conveying device 4 is provided between the feed end and the discharge end of the drying box body 1. In this specific embodiment, the material conveying device 4 is used to transport the material from the feed end to the discharge end until the material is discharged from the drying box. The material is continuously dried during the transportation process in the drying box body 1. In this specific embodiment, the material conveying device 4 can select a traditional crawler conveyor belt, a linear guide rail, a magnetic suspension conveyor belt, etc., and its arrangement in the drying box body 1 can be a linear distribution, a serpentine distribution, etc., which can be controlled by a controller. The controller controls the speed of the material conveying device 4 by accelerating, decelerating, stopping, etc. according to the moisture content of the material at different positions in the drying box body 1, so as to ensure the moisture content of the material when it is discharged from the drying box.

[0034] Among them, the cold air device is connected to each air inlet 2, and is used to provide dry cold air for the air inlet 2 on the drying box body 1, so that the dry cold air temperature of the air inlet 2 on the drying box body 1 close to the feed end is lower than the dry cold air temperature of the air inlet 2 far from the feed end, and the dry cold air temperature of the air inlet 2 located closest to the discharge end is ±5°C of the ambient temperature outside the drying box.

[0035] In one embodiment, in order to avoid the loss of effective ingredients in the material during the drying process, the material is dried at a lower temperature and the temperature gradually increases during transportation in the drying box body 1. The dry cold air temperature range of the air inlet 2 on the drying box body 1 closest to the feed end is 4-10°C, and the dry cold air temperature of the air inlet 2 on the drying box body 1 closest to the discharge end is ±2°C of the ambient temperature outside the drying box. The dry cold air temperature of the air inlet 2 closest to the discharge end is ±2°C of the ambient temperature outside the drying box, which can condense moisture in the air and rehumidify when the material is output from the drying box and comes into contact with the outside air.

[0036] In this embodiment, the cold air device includes a cold air structure, and the cold air structure is connected to the drying box body 1. Figure 1 As shown, the cold air structure includes a cold air processor 5, and the cold air processor 5 includes an air drying device, an air filtering device, and an air compressor. The cold air processor 5 is used to compress, filter, and dry the gas output from the drying box body 1. The dry air output after being processed by the cold air processor 5 has a certain temperature, and it needs to be cooled by heat exchange with the heat exchange structure before it can be used again. The outlet end of the cold air processor 5 is provided with a first cold air outlet main pipe 6, and the first cold air outlet main pipe 6 is provided with at least two cold air outlet branches 7, and the cold air outlet branch pipe 7 is connected to the air inlet 2. The air inlet end of the cold air processor 5 is provided with a cold air intake main pipe 8, and the cold air intake main pipe 8 is provided with at least two cold air intake branches (not shown in the figure), and the cold air intake branch pipe is connected to the return air port 3.

[0037] Preferably, the number of the cold air outlet branch pipes 7 is ≥ the number of the air inlets 2 , and the number of the cold air inlet branch pipes is ≥ the number of the return air outlets 3 .

[0038] In this embodiment, in order to prevent the cold air from flowing back from the drying box body 1 through the cold air outlet branch pipe 7 to the first cold air outlet main pipe 6, or from flowing back through the cold air inlet branch pipe to the cold air inlet main pipe 8, a one-way valve (not shown in the drawings) is provided on each cold air outlet branch pipe 7 and each cold air inlet branch pipe.

[0039] like Figure 1 As shown, the cold air device further includes a heat exchange structure, which is used to exchange heat with the cold air in the first cold air outlet pipe 6, so that the temperature of the cold air in the first cold air outlet pipe 6 gradually increases from the front end to the end of the first cold air outlet pipe 6. Specifically, the temperature of the dry cold air in the first cold air outlet pipe 6 is in the range of 4 to 10°C in the front section of the first cold air outlet pipe 6, and the temperature of the dry cold air gradually increases from the front section to the end, and when the dry cold air reaches the end of the first cold air outlet pipe 6, the temperature is ±2°C of the ambient temperature outside the drying box.

[0040] In this specific embodiment, since the temperature of the cold air at different positions in the first cold air outlet main pipe 6 is different, the temperature of the cold air output by different cold air outlet branch pipes 6 is also different, thereby achieving the purpose of different drying cold air temperatures at different air inlets 2 on different drying box bodies 1.

[0041] In one embodiment of the heat exchange structure, Figure 1 As shown, the heat exchange structure includes a heat exchange tube 10 and a heat exchanger 11. The heat exchange tube 10 is wound on the outer wall of the first cold air outlet main pipe 6. The heat exchange tube 10 exchanges heat with the gas with a higher temperature in the first cold air outlet main pipe 6 to cool it down to form cold air. At the same time, in order to gradually increase the temperature of the gas in the first cold air outlet main pipe 6 from the front end to the rear end, the air inlet end of the heat exchange tube 10 is connected to the air outlet end of the heat exchanger 11, and the air outlet end is connected to the air inlet end of the heat exchanger 11, and the air inlet end of the heat exchange tube 10 is located at the front end of the first cold air outlet main pipe 6, and the air outlet end of the heat exchange tube 10 is located at the end of the first cold air outlet main pipe 6.

[0042] In one embodiment of the cold air drying equipment based on variable temperature and continuous drying of the present specific embodiment, the cold air drying equipment also includes a temperature control structure, which is used to adjust the temperature of the dry cold air output from the drying box body 1 through the air inlet 2, including measuring the temperature of the dry cold air and adjusting the temperature of the dry cold air.

[0043] In one example of a temperature control structure, such as Figure 1 As shown, the temperature control structure includes a first temperature compensation structure 12 and a second temperature compensation structure 13. The first temperature compensation structure 12 is connected to each cold air outlet branch pipe 7 through a pipeline, and is used to cool down the dry cold air input to the drying box body 1. The second temperature compensation structure 13 is a second cold air outlet main pipe connected to the cold air processor 5, and the second cold air outlet main pipe is connected to each cold air outlet branch pipe 7 through a pipeline, and is used to heat up the dry cold air input to the drying box body. The temperature control structure is electrically connected to the controller, and is used to send the detected dry cold air temperature signal in the cold air outlet branch pipe 7 to the controller, and then the dry cold air temperature is controlled by controlling the opening of the first temperature compensation structure 12 or the on-off of the second temperature compensation structure 13.

[0044] In one embodiment of the cold air drying device based on variable temperature and continuous drying of this specific embodiment, as Figure 1 As shown, the cold air drying device also includes a cold air flow control structure, which is used to make the pressure in each place in the drying box body 1 the same. The cold air flow control structure includes flow valves 14 respectively arranged on each cold air outlet branch pipe 7 and each cold air inlet branch pipe, and also includes a plurality of wind speed sensors (not shown in the drawings) and a plurality of air pressure sensors (not shown in the drawings) arranged in the drying box body 1.

[0045] The cold air drying equipment based on variable temperature and continuous drying designed in this specific embodiment first designs a drying box, by providing at least two air inlets 2 and return air inlets 3 corresponding to each air inlet 2 on the drying box body 1 along the direction from the feed end to the discharge end, and at the same time providing a material conveying device 4 between the feed end and the discharge end of the drying box body 1; secondly, the cold air device is connected to the air inlet 2 to provide cold air of no matter the temperature to each air inlet 2, so that the dry cold air temperature of the air inlet 2 close to the feed end is lower than the dry cold air temperature of the air inlet 2 far from the feed end (that is, the dry cold air temperature of the air inlet 2 from the feed end to the discharge end gradually increases).

[0046] When the cold air drying equipment is in operation, the temperature of the cold air that the material just enters the drying box body 1 through the feed end is in contact with is the lowest. As the material is transported from the feed end to the discharge end by the material conveying device, the material is continuously dried, and the temperature of the cold air that the material contacts gradually increases. Finally, the temperature of the dry cold air at the air inlet 2 closest to the discharge end is ±5°C of the external ambient temperature of the drying box body, so that the temperature of the material when it is transported out of the drying box is close to the external ambient temperature, avoiding the phenomenon of moisture recurrence of the material.

[0047] This specific embodiment also provides an application of a cold air drying device based on variable temperature and continuous drying, which can dry any material and is particularly suitable for cold air drying of temperature-sensitive materials.

[0048] Among them, the above-mentioned temperature-sensitive materials include biopolymer materials, Chinese medicinal materials, heat-sensitive additives, health products, etc.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

[0050] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A cold air drying device based on variable temperature and continuous drying, comprising a drying box and a cold air device, characterized in that: The drying box comprises a drying box body, at least two air inlets and return air outlets corresponding to the air inlets are provided along the feeding end to the discharging end of the drying box body, and a material conveying device is provided between the feeding end and the discharging end of the drying box body; The cold air device is connected to each of the air inlets, and is used to provide dry cold air to the air inlets on the drying box body, so that the dry cold air temperature of the air inlet close to the feed end on the drying box body is lower than the dry cold air temperature of the air inlet far from the feed end, and the dry cold air temperature of the air inlet closest to the discharge end is ±5°C of the ambient temperature outside the drying box.

2. The cold air drying equipment based on variable temperature and continuous drying according to claim 1 is characterized in that: The dry cold air temperature of the air inlet on the drying box body closest to the feed end ranges from 4 to 10° C., and the dry cold air temperature of the air inlet on the drying box body closest to the discharge end is ±2° C. of the ambient temperature outside the drying box.

3. The cold air drying equipment based on variable temperature and continuous drying according to claim 1 or 2, characterized in that: The cold air device comprises a cold air structure, and the cold air structure is connected to the drying box body; The cold air structure comprises a cold air processor, the outlet end of the cold air processor is provided with a first cold air outlet main pipe, the first cold air outlet main pipe is provided with at least two cold air outlet branches, the cold air outlet branches are connected with the air inlet; the inlet end of the cold air processor is provided with a cold air inlet main pipe, the cold air inlet main pipe is provided with at least two cold air inlet branches, the cold air inlet branches are connected with the return air port; The cold air device also includes a heat exchange structure, which is used to exchange heat with the cold air in the first cold air outlet pipe, so that the temperature of the cold air in the first cold air outlet pipe gradually increases from the front end to the end of the first cold air outlet pipe.

4. The cold air drying device based on variable temperature and continuous drying according to claim 3 is characterized in that: The number of the cold air outlet branch pipes is ≥ the number of the air inlets, and the number of the cold air inlet branch pipes is ≥ the number of the return air outlets.

5. The cold air drying equipment based on variable temperature and continuous drying according to claim 3 is characterized in that: The heat exchange structure comprises a heat exchange tube, and the heat exchange tube is wound around the outer wall of the first cold air outlet main pipe; The air inlet end of the heat exchange tube is connected to the air outlet end of the heat exchanger, and the air outlet end is connected to the air inlet end of the heat exchanger. The air inlet end of the heat exchange tube is located at the front end of the first cold air outlet main pipe, and the air outlet end of the heat exchange tube is located at the end of the first cold air outlet main pipe.

6. The cold air drying equipment based on variable temperature and continuous drying according to claim 3 is characterized in that: The cold air drying device also includes a temperature control structure, and the temperature control structure is used to adjust the temperature of the dry cold air output from the drying box body through the air inlet.

7. The cold air drying device based on variable temperature and continuous drying according to claim 6, characterized in that: The temperature control structure includes a first temperature compensation structure and a second temperature compensation structure; The first temperature compensation structure is connected to each of the cold air outlet branches via a pipeline, and is used to cool the dry cold air input into the drying box body; The second temperature compensation structure is a second cold air outlet main pipe connected to the cold air processor, and the second cold air outlet main pipe is connected to each of the cold air outlet branches via a pipeline, and is used to heat the dry cold air input into the drying box body.

8. The cold air drying equipment based on variable temperature and continuous drying according to claim 3 is characterized in that: The cold air drying device also includes a cold air flow control structure, which is used to make the pressure in each place of the drying box body the same; The cold air flow control structure includes flow valves respectively arranged on each of the cold air outlet branch pipes and each of the cold air inlet branch pipes, and also includes multiple wind speed sensors and multiple air pressure sensors arranged in the drying box body.

9. An application of a cold air drying device based on variable temperature and continuous drying, characterized in that: The cold air drying equipment according to any one of claims 1 to 8 is used to perform cold air drying on temperature-sensitive materials.

10. The application of the cold air drying equipment based on variable temperature and continuous drying according to claim 9, characterized in that: Temperature sensitive materials include biopolymers.

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