CN106643031A - Internal absorption type solar drier - Google Patents

Abstract

The invention discloses an internal absorption solar dryer, which comprises a solar heat collection device, a drying box and a control system. The inside of the drying box is sequentially arranged with a phase change energy storage drawer, a material drying drawer, and a cross-flow waste heat recovery exchange. The device and the adsorption dehumidification drawer, and a partition is set between the rear inner wall of the drying box, so that the partition and the rear inner wall of the drying box form a preheated air flow channel; the bottom of the drying box is equipped with a circulating fan; the bottom of each layer of drawers is set as a screen Mesh; phase change energy storage materials are placed in the phase change energy storage drawer, materials to be dried are placed in the material drying drawer, and adsorption dehumidification materials are placed in the adsorption dehumidification drawer; air inlet and exhaust are set at the cross-flow waste heat recovery exchanger The thermal superconducting finned tube in the solar heat collection device is located inside the vacuum heat collecting tube; the vacuum heat collecting tube is arranged obliquely, the bottom end is connected to the tube holder and supported by a bracket, and the top is sealed and connected with the upper part of the drying box; the thermal superconducting finned tube extends Into the preheated air passage inside the drying box.

Description

Internal Absorption Solar Dryer

technical field

The invention relates to an internal absorption solar dryer, which uses solar energy to dry materials in agricultural and pastoral areas at medium and low temperatures through thermal superconducting heat transfer technology, phase change energy storage technology and adsorption dehumidification technology, and belongs to the technical field of drying equipment.

Background technique

Solar drying technology is a drying and dehydration technology combined with solar energy utilization technology and drying operation unit technology. Compared with the traditional drying technology, this technology introduces solar energy utilization technology into the drying process, and is applied to the drying process of pasture, grain, seeds, Chinese and Mongolian medicine, food, etc., which not only saves energy, but also protects the environment, and is especially suitable for remote and energy-scarce areas. The material obtained by this drying technology has many advantages: it feels of good quality, and the material basically maintains the inherent color, flavor and aroma of fresh raw materials. The nutrient content is high, because the drying process can be carried out under the condition of constant temperature, which makes the nutrient content loss very little. Thorough dehydration, light weight, suitable for long-term storage and long-distance transportation.

In the early 1990s, my country began to engage in the development of solar drying technology and equipment manufacturing. In the past three to five years, the pasture, grain and other agricultural products industries have developed rapidly. There are dozens of production lines, but most of them are small in scale. In terms of market demand, the development prospect of my country's solar drying technology is extremely broad.

For a long time, in the process of harvesting and preparing hay, the field drying process of forage grass has been the main process of hay preparation in my country. During the forage harvest season, there are very few opportunities for consecutive sunny days. Therefore, due to the wet and rainy forage harvest season in many areas, high-quality forage such as alfalfa cannot be prepared into hay in time, resulting in serious loss of dry matter of forage during field drying. Nutrient retention rate is low. According to the statistics of relevant departments of the Ministry of Agriculture, the annual loss of stored grass in my country is about 300 million tons. Forage drying has become a bottleneck in the production of high-quality hay. The research and development of advanced forage drying equipment is imminent. At present, domestic artificial pasture drying equipment mainly includes drum type forage dryer, 93QH series coal-fired pasture drying unit, 93QH series drying unit, 93QH1000 fuel (gas) pasture drying unit, all of which use fuel oil, coal and gas as the main Therefore, the cost of pasture after drying is relatively high, industrialization is relatively difficult, and the economic benefits are not obvious.

Solar energy is a clean, efficient and inexhaustible new energy source. At present, the governments of various countries regard the utilization of solar energy resources as an important content of the national sustainable development strategy. Solar dryers conform to the development of low-carbon economy, are sustainable, energy-saving and emission-reducing products, and are opportunities for the development of the solar industry. The scale of the solar energy industry is huge, and the market development has great potential. In recent years, the government has vigorously supported the development of the solar energy industry. In 2009, it issued a series of policies for the utilization of solar energy, building a resource-saving and environment-friendly society, and enhancing the requirements for sustainable development. The future of the solar industry is bright, but the road is tortuous. Specific to each enterprise, because each enterprise has different technologies, products and levels, etc., whether it can reach the bright side of the industry depends on the comprehensive strength of the enterprise. At present, the industrial development of my country's solar dryer industry is not standardized, and the self-discipline of enterprises is weak. However, the development of the solar energy industry will surely return to rationality, and enterprises need to pay more attention to the improvement of product quality. The present invention proposes an advanced technical solution for the drying and dehydration of crops, agricultural by-products, seeds, animal husbandry products, and Chinese herbal medicines in the vast rural pastoral areas of our country, which can solve the problems of energy source, environmental pressure, and solar energy utilization cycle. energy efficiency.

Contents of the invention

The invention provides an internal absorption solar dryer, which converts solar radiation energy into heat through a vacuum heat collecting tube, and utilizes thermal superconducting heat transfer technology to conduct heat conduction, which significantly improves heat utilization rate and conduction efficiency; utilizes phase change The energy storage technology balances the temperature change and effectively regulates the drying temperature of the dryer; the air is dehumidified by the adsorption dehumidification technology to obtain dry air, so that the product can be dried at medium and low temperatures in a green, quality-guaranteed, and pollution-free manner.

The technical scheme adopted in the present invention: an internal absorption solar dryer mainly includes a solar heat collecting device, a drying box and a control system, and at least one layer of phase change energy storage drawers and at least one layer of material drying boxes are sequentially arranged inside the drying box from top to bottom. Dry drawer, cross-flow waste heat recovery exchanger and at least one layer of adsorption dehumidification drawer, and a partition is set between the rear inner wall of the drying box, so that the partition and the inner wall of the drying box form a preheated air flow channel; the bottom of the drying box is provided with a circulation fan;

The bottom of the phase change energy storage drawer, material drying drawer and adsorption dehumidification drawer is set in the shape of a screen; solid phase change energy storage materials are placed in the phase change energy storage drawer, materials to be dried are placed in the material drying drawer, and the adsorption dehumidification drawer Place solid adsorption dehumidification materials in the middle; set the air inlet and exhaust outlet at the front end of the drying box corresponding to the cross-flow waste heat recovery exchanger;

The solar heat collection device mainly includes vacuum heat collection tubes, thermal superconducting finned tubes, tube holders and brackets. The thermal superconducting finned tubes are located inside the vacuum heat collecting tubes; The bottom end of the heat pipe is connected to the pipe holder and supported by a bracket; the top of the vacuum heat collection pipe is sealed and connected with the upper part of the drying box, and the thermal superconducting finned tube extends into the preheated air flow channel inside the drying box.

For further optimization, a reflective plate is arranged under the vacuum heat collecting tube, and the reflective plate cooperates with the vacuum heat collecting tube and is placed obliquely and supported by a bracket. The reflective plate reflects the sunlight passing through the vacuum heat collecting tube, so that the backlight surface of the vacuum heat collecting tube can also receive sunlight, thereby improving the solar heat collection efficiency and the heat collection amount per unit area.

Further optimization, the corresponding positions on the left and right inner walls of the drying box are provided with slides supporting the phase change energy storage drawer, material drying drawer, cross-flow waste heat recovery exchanger and adsorption dehumidification drawer, so that each drawer can be conveniently drawn by pulling the corresponding drawers. Picking and replacing of materials.

Further optimized, corresponding airtight doors are set at the front end of the drying box corresponding to the phase change energy storage drawer, material drying drawer, and adsorption dehumidification drawer to play a sealing role and prevent heat loss inside the drying box.

Further optimized, the part where the thermal superconducting finned tube protrudes into the drying box is provided with cooling fins, so that the dry air flowing through the cooling fins can quickly and fully absorb heat for preheating.

Further optimized, the thermal insulation material is pasted on the inner wall of the drying box to form an insulating layer, which can effectively prevent the heat loss inside the drying box.

Further optimization, the humidity sensor is installed in the adsorption dehumidification drawer, and is connected with the control system to monitor the change of humidity, and remind to replace the adsorption dehumidification material in time; the circulation fan is connected to the control system to realize the adjustment of the circulation air volume.

Further optimized, a temperature sensor and a humidity sensor are installed in the material drying drawer, and are connected with the control system to monitor and control the drying condition of the material to be dried.

Further optimized, the adsorption dehumidification drawer is set to two layers, the first layer is placed with super absorbent sponge, and the second layer is placed with super absorbent resin.

The vacuum heat collecting tube in the solar heat collecting device in the present invention absorbs solar energy and provides the heat source required for drying materials; the thermal superconducting finned tube conducts heat efficiently, and conducts the heat from the vacuum heat collecting tube to the preheater inside the drying box. The hot air flow path is used to preheat the dry air passing through the heat sink. Inside the drying box, under the action of the circulating fan, the dry air flows upwards and enters the preheating air passage. Dry air absorbs heat as it flows through the fins, resulting in preheated air. Then, the preheated air turns around and flows downward, and flows through the phase change energy storage drawer, material drying drawer, cross-flow waste heat recovery exchanger and adsorption dehumidification drawer in order from top to bottom, realizing the circulation flow inside the drying box.

When the preheated air flows through the phase change energy storage drawer, if the temperature of the preheated air is higher than the energy storage temperature of the solid phase change energy storage material, part of the heat in the preheated air can be transferred to the solid phase change energy storage material for storage When the preheated air temperature is lower than the energy storage temperature, the solid phase change energy storage material releases its stored heat to further preheat the preheated air. Through the process of storing or releasing heat by the solid phase-change energy storage material, the fluctuation of heat with solar energy can be balanced, the temperature change of the drying box can be effectively regulated, and the drying time can be extended and the drying rate can be increased.

When the preheated air flows through the material drying drawer, it is dried by contacting the material to be dried placed in it, and the moisture evaporated from the material to be dried is taken away, and becomes moisture-containing air. This method of preheating the air to contact the material to be dried and take away the evaporated water can significantly improve the drying efficiency.

When the moisture-containing air flows through the cross-flow waste heat recovery exchanger, a part of the moisture-containing air enters the vertical and horizontal elbows in the cross-flow waste heat recovery exchanger, and the residual heat is used to preheat the new air entering from the air inlet, and then Exhausted from the exhaust port, which improves the overall utilization of heat. Another part of the moisture-laden air enters the vertical tubes in the cross-flow waste heat recovery exchanger and then directly into the adsorption dehumidification drawer.

When the moisture-containing air flows through the adsorption dehumidification drawer, the adsorption dehumidification material absorbs water and dehumidifies the moisture-containing air, and at the same time dries and dehumidifies the incoming new air, thereby obtaining dry air. The dry air flows upwards under the action of the circulating fan, and returns to the preheated air channel for the next cycle.

The integrated small box-type dryer using solar energy in the present invention has high device integration, compact structure, small footprint, and neat appearance; the use of thermal superconducting finned tubes to conduct heat improves the conduction rate and reduces the heat transfer rate during the conduction process. Heat loss; use the drawer structure to place various materials, so as to facilitate the taking or replacement of various materials; use the process of storing or releasing heat of solid phase change energy storage materials to balance the fluctuation of the temperature of the preheated air and prolong the drying time ;By preheating the air in contact with the material to be dried and taking away the evaporated water, the drying efficiency and speed are improved; the air is continuously circulated inside the drying box by using the sealing effect of the airtight door and the heat preservation effect of the insulation layer, reducing the drying time. The heat loss is greatly improved, and the overall utilization rate of heat is significantly improved; the temperature sensor and the humidity sensor are connected to the control system to monitor the drying situation and realize digital control; the invention can be widely used in rural pastoral areas for grain, seeds, fruits and vegetables, Drying of agricultural by-products, meat, and Chinese herbal medicines.

Description of drawings

Fig. 1 is the front view of device of the present invention;

Fig. 2 is a rear view of the device of the present invention;

Fig. 3 is a side view of the device of the present invention;

Fig. 4 is a top view of the device of the present invention;

Fig. 5 is a sectional view of the device of the present invention.

detailed description

The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figures 1-5, the present invention mainly includes a solar heat collection device, a drying box 1 and a control system. A layer of phase-change energy storage drawer 2 and a three-layer material drying drawer are sequentially arranged inside the drying box 1 from top to bottom. 3. The cross-flow waste heat recovery exchanger 4 and the two-layer adsorption dehumidification drawer 5, and a partition 6 is set between the rear inner wall of the drying box 1, so that the partition 6 and the inner wall of the drying box 1 form a preheating air flow channel 7; A circulation fan 8 is arranged at the bottom of the box 1; thermal insulation material is pasted on the inner wall of the drying box 1 to form a thermal insulation layer 16;

The bottoms of phase change energy storage drawer 2, material drying drawer 3 and adsorption dehumidification drawer 5 are set in the shape of a screen; solid phase change energy storage material is placed in phase change energy storage drawer 2, and the material drying drawer 3 is placed to be dried Materials, solid adsorption dehumidification materials are placed in the adsorption dehumidification drawer 5; the adsorption dehumidification drawer 5 is set in two layers, the first layer is placed with super absorbent cotton, and the second layer is placed with super absorbent resin;

The front end of the drying box 1 corresponding to the cross-flow waste heat recovery exchanger 4 is provided with an air inlet 9 and an exhaust port 10; the corresponding positions on the left and right inner walls of the drying box 1 are provided with supporting phase change energy storage drawers 2, material drying drawers 3, The cross-flow waste heat recovery exchanger 4 and the slideway of the adsorption dehumidification drawer 5; the phase change energy storage drawer 2, the material drying drawer 3, and the front end of the drying box 1 corresponding to the adsorption dehumidification drawer 5 are respectively provided with corresponding airtight doors 18;

The solar heat collecting device mainly includes a vacuum heat collecting tube 11, a thermal superconducting finned tube 12, a tube support 13 and a bracket 14, and the thermal superconducting finned tube 12 is located inside the vacuum heat collecting tube 11; -45 degree angle; the bottom end of the vacuum heat collecting tube 11 is connected to the tube support 13 and supported by a bracket 14; the top of the vacuum heat collecting tube 11 is sealed and connected to the upper part of the drying box 1, and the thermal superconducting finned tube 12 extends into the drying box 1 The inner preheating air channel 7; the thermal superconducting finned tube 12 extending into the part of the drying box 1 is provided with a cooling fin 17; Cooperate with inclined placement and support with bracket 14;

A humidity sensor is set in the adsorption dehumidification drawer 5 and connected to the control system; a circulation fan 8 is connected to the control system; a temperature sensor and a humidity sensor are set in the material drying drawer 3 and connected to the control system.

The vacuum heat collection tube 11 in the solar heat collection device of the present invention is used to absorb solar energy, and the sunlight is directly irradiated or reflected on the vacuum heat collection tube 11 through the reflector 15, and the vacuum heat collection tube 11 converts the absorbed solar radiation energy into heat energy, providing The heat required to dry the material. The thermal superconducting finned tube 12 conducts heat efficiently, conducts heat from the vacuum heat collecting tube 11 to the preheated air flow channel 7 inside the drying box 1, and preheats the dry air flowing through the place through the heat sink 17 .

Inside the drying box 1 , under the action of the circulating fan 8 , the dry air flows upwards and enters the preheating air passage 7 . The dry air absorbs heat when flowing through the cooling fins 17 to obtain preheated air. Then, the preheated air turns around and flows downward, and flows through the phase change energy storage drawer 2, the material drying drawer 3, the cross-flow waste heat recovery exchanger 4 and the adsorption dehumidification drawer 5 in order from top to bottom, realizing the drying of part of the hot air. Circulating flow inside the tank.

When the preheated air flows through the phase change energy storage drawer 2, if the temperature of the preheated air is higher than the energy storage temperature of the solid phase change energy storage material, part of the heat in the preheated air can be transferred to the solid phase change energy storage material Stored; when the preheated air temperature is lower than the energy storage temperature, the solid phase change energy storage material releases its stored heat to further preheat the preheated air. Through the process of storing or releasing heat by the solid phase-change energy storage material, the fluctuation of heat generated by the change of solar energy can be balanced, the temperature change of the drying box 1 can be effectively regulated, and the drying time and drying rate can also be prolonged.

When the preheated air flows through the material drying drawer 3, it is dried by contacting the material to be dried placed therein, and the moisture evaporated from the material to be dried is taken away, and becomes moisture-containing air. This method of preheating the air to contact the material to be dried and take away the evaporated water can significantly improve the drying efficiency. The temperature sensor and the humidity sensor in the material drying drawer 3 can monitor the drying situation of the material to be dried. Drying materials, and convenient replacement of the next batch of materials to be dried.

When the moisture-containing air flows through the cross-flow waste heat recovery exchanger 4, a part of the moisture-containing air enters the vertical and horizontal elbows in the cross-flow waste heat recovery exchanger 4, and the residual heat is used to preliminarily pre-condition the new air entering from the air inlet 9. The heat is then discharged from the exhaust port 10, thereby improving the overall utilization of heat. The other part of moisture-containing air enters the vertical pipe in the cross-flow waste heat recovery exchanger 4, and then directly enters the adsorption dehumidification drawer 5.

When the moisture-containing air flows through the adsorption dehumidification drawer 5, the super-absorbent sponge placed on the first layer first absorbs water from the moisture-containing air; then, the superabsorbent resin placed on the second layer performs secondary dehumidification to obtain dry air. At the same time, the incoming new air also needs to flow through the adsorption dehumidification drawer 5 for drying and dehumidification, and becomes dry air. The dry air flows upwards under the action of the circulating fan 8, and returns to the preheated air channel 7 for the next cycle. The humidity sensor of the adsorption dehumidification drawer 5 can detect the humidity change of the adsorption dehumidification material. When the control system reminds that the adsorption dehumidification material needs to be replaced, by opening the corresponding airtight door 18 and pulling out the adsorption dehumidification drawer 5, a new adsorption dehumidification material can be easily replaced. dehumidifying material.

Finally, it should be noted that the above text and accompanying drawings have described the main structural features and working principles of the present invention, but those skilled in the art should understand that the present invention is not limited by the above-mentioned specific implementation methods, without departing from the basic principles of the present invention. Under the premise of the design concept, various deformation modes of the present invention should also be within the protection scope of the present invention.

Claims (9)

1. Internal absorption solar dryer, mainly including solar heat collector, drying box (1) and control system, characterized in that at least one layer of phase change energy storage drawers ( 2), at least one layer of material drying drawer (3), cross-flow waste heat recovery exchanger (4) and at least one layer of adsorption dehumidification drawer (5), and a partition (6) between the rear inner wall of the drying box (1) ), so that the partition (6) and the inner wall of the drying box (1) form a preheating air flow channel (7); the bottom of the drying box (1) is provided with a circulating fan (8); The bottoms of the phase-change energy storage drawer (2), the material drying drawer (3) and the adsorption dehumidification drawer (5) are set in the shape of a screen; the phase-change energy storage drawer (2) places solid phase-change energy storage Place materials to be dried in the dry drawer (3), place solid adsorption dehumidification materials in the adsorption dehumidification drawer (5); set an air inlet (9) at the front end of the drying box (1) corresponding to the cross-flow waste heat recovery exchanger (4) and exhaust port (10); The solar heat collecting device mainly includes a vacuum heat collecting tube (11), a thermal superconducting finned tube (12), a tube holder (13) and a support (14), and the thermal superconducting finned tube (12) is positioned on the vacuum heat collecting tube (11) Inside; the vacuum heat collection tube (11) is inclined to form an angle of 15-45 degrees with the horizontal plane; the bottom end of the vacuum heat collection tube (11) is connected to the pipe holder (13) and supported by a bracket (14); the top of the vacuum heat collection tube (11) is connected to the The upper part of the drying box (1) is sealed and connected, and the thermal superconducting finned tube (12) extends into the preheated air flow channel (7) inside the drying box (1). 2. The internal absorption solar dryer according to claim 1, characterized in that: a reflective plate (15) is arranged under the vacuum heat collecting tube (11), and the reflective plate (15) cooperates with the vacuum heat collecting tube (11) to tilt Place and support with bracket (14). 3. The internal absorption solar dryer according to claim 1, characterized in that: supporting phase change energy storage drawers (2) and material drying drawers (3) are provided at corresponding positions on the left and right inner walls of the drying box (1) , The cross-flow waste heat recovery exchanger (4) and the slideway of the adsorption dehumidification drawer (5). 4. The internal absorption solar dryer according to claim 1, characterized in that: the phase change energy storage drawer (2), the material drying drawer (3), and the drying box (1) corresponding to the adsorption dehumidification drawer (5) Corresponding airtight doors (18) are respectively arranged at the front ends. 5. The internal absorption solar dryer according to claim 1, characterized in that: heat dissipation fins (17) are provided on the part of the thermal superconducting finned tube (12) protruding into the interior of the drying box (1). 6. The internal absorption solar dryer according to claim 1, characterized in that: the inner wall of the drying box (1) is pasted with thermal insulation material to form a thermal insulation layer (16). 7. The internal absorption solar dryer according to any one of claims 1-6, characterized in that: a humidity sensor is installed in the adsorption dehumidification drawer (5), and is connected to the control system; the circulation fan (8) is connected to the control system connect. 8. The internal absorption solar dryer according to any one of claims 1-6, characterized in that: a temperature sensor and a humidity sensor are installed in the material drying drawer (3), and are connected to the control system. 9. The internal absorption solar dryer according to any one of claims 1-6, characterized in that: the adsorption dehumidification drawer (5) is arranged in two layers, the first layer is placed with super absorbent sponge, and the second layer is placed with high Absorbent resin.