Multi-section efficient dehumidification system used in VOC volatile environment

Abstract

The invention relates to a multi-section efficient dehumidification system used in a VOC volatile environment, and relates to the technical field of VOC treatment.The dehumidification system comprises an adsorption tower, a drying mechanism, a heat exchanger and a heater, the adsorption tower is used for adsorbing VOC in tail gas exhausted by a crystallizer and then inputting the VOC into the heat exchanger, and the drying mechanism is used for drying the VOC in the tail gas; the drying mechanism is used for drying air, inputting the dried air into the heat exchanger for heat exchange with tail gas and preheating the air, and the heater is used for heating the preheated air and inputting the heated air into the crystallizer. According to the device, air is dried through the drying mechanism to form dry air, then heat exchange can be conducted on heat of tail gas and the dry air through the heat exchanger to preheat the dry air, and therefore energy saving is achieved, and pollution to the environment is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of VOC treatment, and in particular to a multi-stage high-efficiency dehumidification system for use in an environment where VOCs are volatile. Background Art

[0002] The demand for plastics in modern life is increasing, and the recycling of waste plastics has also become a trend. Recycling, washing and granulating waste plastics is a way to turn waste into treasure and reuse resources.

[0003] In the production of plastic granulation, plastic particles need to be dried and crystallized. The traditional drying and crystallization process uses circulating air for drying. Although this method is economical and efficient, when dealing with plastic particles containing VOC air, the VOC air cannot be effectively discharged through circulation; on the other hand, some dehumidifiers use fresh air for dehumidification and discharge hot and humid air directly into the atmosphere, which not only wastes heat energy, but may also pollute the environment. Summary of the invention

[0004] In order to achieve energy saving and reduce pollution to the environment, the present application provides a multi-stage high-efficiency dehumidification system for use in a VOC volatile environment.

[0005] The present application provides a multi-stage high-efficiency dehumidification system for use in a VOC volatile environment, which adopts the following technical solutions: A multi-stage high-efficiency dehumidification system for use in an environment where VOC is volatile, comprising an adsorption tower, a drying mechanism, a heat exchanger, and a heater. The adsorption tower is used to adsorb VOC in the tail gas discharged from a crystallizer and then input the air into the heat exchanger; the drying mechanism is used to dry the air and then input the air into the heat exchanger to exchange heat with the tail gas and to preheat the air; the heater is used to heat the preheated air and then input the air into the crystallizer.

[0006] By adopting the above technical solution, the air is dried by the drying mechanism to form dry wind, and then the dry wind enters the heat exchanger, and the exhaust gas generated in the crystallizer is first treated by the adsorption tower to adsorb VOC in the exhaust gas, and then the exhaust gas also enters the heat exchanger, and the exhaust gas and the dry wind exchange heat, so that the heat in the exhaust gas can preheat the dried wind, and finally the temperature of the exhaust gas is greatly reduced and then discharged into the air. At the same time, the preheated wind is heated by the heater and then enters the crystallizer to heat the plastic particles.

[0007] The air is first dried by a drying mechanism to form dry wind, and then the heat of the exhaust gas is exchanged with the dry wind through a heat exchanger to preheat the dry wind. This greatly reduces the temperature of the exhaust gas discharged into the air, while also increasing the temperature of the dry wind, thereby reducing the thermal pollution caused by the exhaust gas to the air and reducing the thermal energy required for heating by the heater, thereby achieving energy saving and reducing pollution to the environment.

[0008] Optionally, the drying mechanism includes: Condenser, used to condense the air to remove moisture; The molecular sieve dryer is connected to the condenser and the heat exchanger and is used to dry the air processed by the condenser and input the dried gas into the heat exchanger.

[0009] By adopting the above technical solution, the air is first condensed by the condenser to remove moisture, and then the air enters the molecular sieve dryer to be dried again, thereby forming dry wind, thereby achieving wind drying.

[0010] Thereby, the following effects can be achieved: 1. Heat is recycled under the action of the heat exchanger; 2. The dry air entering the heater is preheated. The temperature of the dry air after condensation is relatively low. It will inevitably consume a lot of thermal energy to reach the temperature required for crystallization. The waste heat of the hot air coming out of the adsorption tower is used to heat the dry air, which greatly reduces the power requirement of the heater; 3. After the hot air coming out of the adsorption tower exchanges heat through the heat exchanger, the temperature drops to a temperature close to that of natural wind, and is then discharged into the outside atmosphere from the exhaust port, thereby reducing pollution to the atmosphere and adverse effects on the surrounding weather.

[0011] Optionally, the connection points of the molecular sieve dryer and the adsorption tower with the heat exchanger are located on the same side of the heat exchanger, and the positions where the air and the condensing agent enter the condenser are located on the same side of the condenser.

[0012] By adopting the above technical solution, the temperature of the dry air is the lowest when it is input into the heat exchanger, and the temperature of the exhaust gas is the highest when it enters the heat exchanger. Therefore, at this time, the temperature difference between the exhaust gas and the dry air is the largest when they are exchanged. The greater the temperature difference, the higher the heat exchange efficiency between the exhaust gas and the dry air, thereby greatly accelerating the heat exchange efficiency between the two. At the same time, the temperature of the air is the highest when it enters the condenser, and the temperature of the refrigerant is the lowest when it enters the condenser. Therefore, at this time, the temperature between the two is the largest when they are heat exchanged. Similarly, the condensation and drying efficiency of the air can be improved, thereby further achieving energy saving and reducing pollution to the environment.

[0013] Optionally, the heat exchanger is provided with an input pipe connected to the adsorption tower and an output pipe for outputting gas, and the input pipe and the output pipe are provided with a control mechanism, and the control mechanism detects that the exhaust gas temperature in the output pipe is A, and when B≤A<C, the control mechanism controls the exhaust gas output speed in the output pipe to gradually slow down as the temperature rises, and when C≤A, the control mechanism blocks the output pipe and allows the gas in the output pipe to flow back to the input pipe to continue heat exchange.

[0014] By adopting the above technical solution, the temperature of the tail gas output by the adsorption tower is higher than the external environment, so it is easy for the temperature of the tail gas to be higher than the external temperature after heat exchange, so that the heat pollution to the air is still high, and the heat utilization of the tail gas is insufficient; The exhaust gas in the heat exchanger is output through the output pipe. The control mechanism is used to detect the exhaust gas temperature in the output pipe. When the air temperature is between B and C, B or C can be designed as the temperature of the external environment, and the control mechanism controls the exhaust gas output speed of the output pipe. The speed gradually slows down as the temperature rises. The slower the speed, the longer the exhaust gas stays in the heat exchanger, so that the exhaust gas can have a longer time to exchange heat with the dry air, thereby further reducing the temperature of the exhaust gas passing through the output pipe, thereby reducing the probability of thermal pollution to the external environment, and trying to exchange the heat of the exhaust gas with the dry air, thereby achieving energy saving and reducing pollution to the environment.

[0015] When the temperature is greater than C, it means that the temperature of the exhaust gas output from the output pipe is high, and the temperature of the exhaust gas cannot be controlled below the requirement by simply controlling the exhaust gas output speed. In this case, the control mechanism controls the exhaust gas in the output pipe to flow back into the input pipe, and the returned exhaust gas can continue to exchange heat with the newly entered exhaust gas and the dry air, thereby further reducing the temperature of the exhaust gas output from the output pipe, thereby further achieving energy saving and reducing pollution to the environment.

[0016] Optionally, the control mechanism includes: A temperature detector, arranged in the output pipe and used to detect the exhaust gas temperature; The annular airbag is arranged in the output pipe and expands and contracts as the temperature rises and decreases after contacting the exhaust gas, so that the blocking effect on the exhaust gas gradually increases as the temperature rises; The reflux component is arranged on the output pipe and is connected with the input pipe. When the temperature detector detects that the temperature is greater than C, the reflux component starts to block the output pipe and refluxes the gas in the output pipe into the input pipe.

[0017] By adopting the above technical solution, the temperature detector is used to detect the temperature of the exhaust gas. When the temperature of the exhaust gas is between B and C, the temperature of the exhaust gas can cause the annular airbag to change with the temperature. Therefore, the higher the temperature, the greater the blocking effect of the annular airbag on the exhaust gas after expansion, and the movement speed of the exhaust gas slows down. When the temperature becomes lower, the annular airbag contracts and the blocking effect on the exhaust gas is reduced, and the movement speed of the exhaust gas becomes faster. Therefore, when the temperature is between B and C, the movement speed of the exhaust gas is controlled according to the temperature.

[0018] When the temperature is greater than C, the annular airbag expands to slow down the speed of air movement. At the same time, the reflux component starts to block the output pipe and reflux the exhaust gas to the input pipe for treatment. The exhaust gas is processed by the annular airbag and the reflux component at the same time, which greatly reduces the temperature of the exhaust gas at output, thereby achieving energy saving and reducing pollution to the environment.

[0019] Optionally, the reflux component includes: The reflux pipe and the vent pipe are connected to the output pipe through a three-way valve, the three-way valve is electrically connected to the temperature detector and controls the output pipe to be connected to the reflux pipe or the vent pipe; the end of the reflux pipe away from the output pipe is connected to the input pipe through a one-way valve, and the one-way valve allows the exhaust gas in the reflux pipe to only enter the input pipe.

[0020] By adopting the above technical solution, when the temperature is greater than C, the three-way valve controls the output pipe to be connected with the reflux pipe, and the exhaust gas in the output pipe enters the input pipe through the reflux pipe and the one-way valve for reflux; when the temperature is less than C, the three-way valve controls the output pipe to be connected with the ventilation pipe, so that the exhaust gas in the output pipe is discharged into the external environment through the ventilation pipe, thereby realizing the reflux or discharge of exhaust gas into the external environment.

[0021] Optionally, the thickness of the inner side wall of the annular airbag is the thinnest and the inner side wall of the annular airbag is deformed first.

[0022] By adopting the above technical solution, the sensitivity of control is improved, thereby achieving energy saving and reducing pollution to the environment.

[0023] Optionally, the condenser comprises: The machine body has a condensation chamber formed therein; an infusion tube passing through the condensation chamber and used for conveying the condensing agent; The air inlet pipe and the air outlet pipe are arranged on opposite side walls of the machine body and are connected to the condensation chamber and are used to input and output air respectively. The air in the condensation chamber contacts the liquid infusion tube and is used to achieve condensation. A plurality of water-permeable micropores connected to the condensation chamber and for water to be immersed are opened on the lower surface of the machine body; The collecting box is arranged on the machine body and is used for collecting condensed water passing through the water-passing micropores.

[0024] By adopting the above technical solution, air is input into the condensation chamber through the air inlet pipe, and at the same time, the condensing agent is input into the infusion tube. The condensing agent is used to cool the air in the condensation chamber, so that the water in the air condenses and penetrates into the water-permeable micropores, and finally the water drops into the collection box for collection. Finally, the air is dried and output through the air outlet pipe, thereby achieving air drying.

[0025] Optionally, the infusion tube located in the condensation chamber is spiral-shaped and forms a first chamber and a second chamber for air to pass through with the bottom and side walls of the condensation chamber, respectively.

[0026] By adopting the above technical solution, the air gradually gathers in the first chamber after entering the condensation chamber, and then moves upward into the second chamber, so that the air can move around the side of the infusion tube, and the infusion tube is spiral, which greatly increases the area of ​​heat exchange between the condensing agent and the air, thereby improving the air drying efficiency and effect, so that the moisture in the air condenses and falls downward, or the moisture condenses on the infusion tube, thereby greatly improving the air drying efficiency and effect.

[0027] Optionally, a smooth layer that facilitates heat transfer and water droplets falling is provided on the infusion tube located in the condensation chamber.

[0028] By adopting the above technical solution, the smooth layer is more convenient for water drops to fall off, thereby further improving the drying efficiency and effect of the air.

[0029] In summary, the present application includes at least one of the following beneficial technical effects: The air is first dried by a drying mechanism to form dry wind, and then the heat of the exhaust gas is exchanged with the dry wind through a heat exchanger to preheat the dry wind. This greatly reduces the temperature of the exhaust gas discharged into the air, while also increasing the temperature of the dry wind, thereby reducing the thermal pollution caused by the exhaust gas to the air and reducing the thermal energy required for heating by the heater, thereby achieving energy saving and reducing pollution to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a structural schematic diagram of a first embodiment of a dehumidification system; Figure 2 is a schematic diagram of the structure of a second embodiment of a dehumidification system; Figure 3 is a schematic diagram of the structure of the condenser in the second embodiment of the dehumidification system, wherein two side walls of the body are cut away; Figure 4 is a schematic diagram of the structure of the heat exchanger and the control mechanism in the second embodiment of the dehumidification system; Figure 5 It is a structural diagram of the control mechanism in the second embodiment of the dehumidification system.

[0031] Figure numerals: 1. crystallizer; 11. adsorption tower; 12. heat exchanger; 13. heater; 14. input pipe; 15. output pipe; 16. inlet pipe; 17. through pipe; 2. drying mechanism; 21. molecular sieve dryer; 3. condenser; 31. machine body; 32. infusion tube; 33. air inlet pipe; 34. air outlet pipe; 35. collecting box; 36. condensation chamber; 37. water-passing micropores; 38. first chamber; 39. second chamber; 4. control mechanism; 41. temperature detector; 42. annular airbag; 5. reflux assembly; 51. reflux pipe; 52. vent pipe; 53. three-way valve; 54. connecting pipe; 55. one-way valve. DETAILED DESCRIPTION

[0032] The following is combined with Figure 1-5 This application is described in further detail.

[0033] The embodiment of the present application discloses a multi-stage high-efficiency dehumidification system for use in an environment where VOCs are volatile.

[0034] Embodiment 1 Reference Figure 1 The multi-stage high-efficiency dehumidification system for VOC volatile environments includes an adsorption tower 11, a drying mechanism 2, a heat exchanger 12, and a heater 13. The adsorption tower 11 is used to adsorb VOC in the exhaust gas discharged from the crystallizer 1, and then the treated exhaust gas is input into the heat exchanger 12; the air or the pre-dried dry air is further dried by the drying mechanism 2 to form dry wind, and the dry wind is also input into the heat exchanger 12. The dry wind exchanges heat with the exhaust gas, thereby cooling the exhaust gas and preheating the dry wind. The exhaust gas is discharged through the heat exchanger 12, and the preheated dry wind is heated by the heater 13 and then input into the crystallizer 1, thereby drying and crystallizing the plastic particles in the crystallizer 1.

[0035] An input pipe 14 and an output pipe 15 are fixedly installed on both ends of the heat exchanger 12. The input pipe 14 is connected to the adsorption tower 11 and is used to input the exhaust gas after adsorption treatment into the heat exchanger 12. The output pipe 15 is used to output air and discharge it into the external environment; an inlet pipe 16 connected to the heat exchanger 12 is fixedly installed on the molecular sieve dryer 21, and a through pipe 17 connected to the heater 13 is fixedly installed on the heat exchanger 12.

[0036] The drying mechanism 2 includes a condenser 3 and a molecular sieve dryer 21. The condenser 3 and the molecular sieve dryer 21 adopt existing structures, so they are not described here. The air is condensed by the condenser 3, so that the moisture in the air is condensed and removed, and then the air is dried by the molecular sieve dryer 21 to form dry wind. The dry wind is input into the heat exchanger 12, and the exhaust gas also enters the heat exchanger 12 after being adsorbed by the adsorption tower 11, so that the exhaust gas and the dry wind are heat exchanged, so as to preheat the dry wind. After preheating, the dry wind is heated by the heater 13 and then enters the crystallizer 1 for heating, so as to heat, dry and crystallize the plastic particles, reducing the heat energy consumed by the heater 13 during heating. At the same time, the exhaust gas is discharged through the heat exchanger 12, so that the temperature of the exhaust gas is greatly reduced, and the probability of thermal pollution caused by the exhaust gas to the environment is reduced.

[0037] The working principle of the embodiment of the present application is as follows: The air is dried by the condenser 3 and the molecular sieve dryer 21 in turn to form dry wind, which is input into the heat exchanger 12. The tail gas also enters the heat exchanger 12 after being adsorbed by the adsorption tower 11. The tail gas and the dry wind perform heat exchange, thereby preheating the dry wind and greatly reducing the temperature of the tail gas. After preheating, the dry wind is heated by the heater 13 and then enters the crystallizer 1 for heating. At the same time, the tail gas is discharged through the heat exchanger 12, thereby achieving energy saving and reducing pollution to the environment.

[0038] Embodiment 2 Reference Figure 2 and Figure 3 The difference between this embodiment and embodiment 1 is that the condenser 3 includes a body 31, a liquid infusion tube 32, an air inlet pipe 33, an air outlet pipe 34 and a collection box 35; a control mechanism 4 is provided on the input pipe 14 and the output pipe 15, and the control mechanism 4 is used to detect the exhaust gas temperature in the output pipe 15, thereby controlling the exhaust gas output speed in the output pipe 15 according to the temperature.

[0039] The body 31 is in the shape of a rectangular parallelepiped and has a condensation chamber 36 opened inside along its length. One end of the infusion tube 32 passes through the upper surface of one end of the body 31 and extends into the condensation chamber 36 and passes through the upper surface of the other end. The infusion tube 32 is used to transport a refrigerant, which can be frozen water or other refrigerants. At the same time, the infusion tube 32 located in the condensation chamber 36 is spiral along the length direction of the body 31 and is coated with a smooth layer on the outer wall. The smooth layer is made of metal material and has a higher thermal conductivity than the infusion tube 32. At the same time, the roughness of the smooth layer is less than the roughness of the outer wall of the infusion tube 32, so that the smooth layer facilitates heat conduction in the infusion tube 32 and causes condensed water droplets to fall off.

[0040] The air inlet pipe 33 and the air outlet pipe 34 are fixedly installed on both ends of the body 31, and the air inlet pipe 33 and the air outlet pipe 34 are connected to the condensation chamber 36. At the same time, the connection between the air inlet pipe 33 and the air outlet pipe 34 and the body 31 is located on the side close to the lower surface of the body 31, and the air outlet pipe 34 is connected to the molecular sieve dryer 21. At the same time, the air inlet pipe 33 is used to input air into the condensation chamber 36, and the infusion pipe 32 conveys the condensing agent, so that the air and the condensing agent located in the infusion pipe 32 perform heat exchange, so that the moisture in the air condenses into liquid and falls downward, or the moisture condenses on the smooth layer and then falls downward. Finally, the air is output through the air outlet pipe 34 and enters the molecular sieve dryer 21 for re-drying, while the condensing agent continues to be conveyed.

[0041] The point where the air enters the condensation chamber 36 and the point where the refrigerant enters the infusion tube 32 located in the condensation chamber 36 are located on the same side of the body 31, so that the air temperature is the highest and the refrigerant temperature is the lowest when the air and the refrigerant exchange heat, so that the air and the refrigerant form the largest temperature difference, thereby improving the heat exchange efficiency when the two exchange heat.

[0042] A plurality of water-passing micropores 37 connected to the lower surface of the machine body 31 are evenly arranged on the inner bottom wall of the condensation chamber 36. The water-passing micropores 37 are relatively small in size and are designed according to needs so that water droplets are discharged after being immersed in the water-passing micropores 37. The water-passing micropores 37 have a relatively small diameter and the air moves upward, so that it is not easy for air to enter the water-passing micropores 37. The collecting box 35 is fixedly mounted on the lower surface of the machine body 31 by screws, and the water droplets passing through the water-passing micropores 37 fall into the collecting box 35 for collection.

[0043] A first chamber 38 and a second chamber 39 are formed between the infusion tube 32 located in the condensation chamber 36 and the inner bottom wall and two opposite side walls of the condensation chamber 36. The second chamber 39 has two and is interconnected. Due to the existence of the infusion tube 32, the width of the first chamber 38 is greater than the width of the second chamber 39. After entering the first chamber 38, the air spreads upward to the two second chambers 39 and moves in the two second chambers 39, so that the air can move around the infusion tube 32, thereby increasing the area of ​​heat exchange between the air and the condensing agent in the infusion tube 32 and improving the condensation and dehumidification effect of the air.

[0044] The connection points between the inlet pipe 16 and the through pipe 17 and the heat exchanger 12 are respectively located at the two ends of the heat exchanger 12, and the connection point between the inlet pipe 16 and the heat exchanger 12 is located on the side close to the input pipe 14. The inlet pipe 16 is used to input dry air. After the dry air and the exhaust gas exchange heat, the dry air enters the heater 13 through the through pipe 17 for heating. At the same time, the temperature of the dry air that has just entered the heat exchanger 12 for heat exchange with the exhaust gas is the lowest and the temperature of the exhaust gas is the highest, so that the temperature difference between the exhaust gas and the dry air is maximized during the heat exchange, thereby improving the heat exchange efficiency of the two during heat exchange.

[0045] Reference Figure 2 and Figure 4 The control mechanism 4 detects the temperature of the exhaust gas as A. When B≤A<C, the control mechanism 4 controls the exhaust gas output speed in the output pipe 15 to gradually slow down as the temperature rises. When C≤A, the control mechanism 4 blocks the output pipe 15 and allows the air in the output pipe 15 to flow back to the input pipe 14 to continue heat exchange; the temperatures of A, B, and C are designed according to actual conditions, so that the exhaust gas temperature is closer to the temperature of the external environment, thereby utilizing the exhaust gas heat energy as much as possible and reducing the probability of thermal pollution to the environment.

[0046] Reference Figure 4 and Figure 5 The control mechanism 4 includes a temperature detector 41, an annular airbag 42 and a reflux component 5. A connecting pipe 54 is detachably installed at one end of the output pipe 15 away from the heat exchanger 12. One end of the connecting pipe 54 is coaxially threadedly connected to the inner wall of the output pipe 15, so that the exhaust gas in the output pipe 15 enters the connecting pipe 54 for transportation; the temperature detector 41 is fixedly installed on one end of the connecting pipe 54 located in the output pipe 15 and is used to detect the exhaust gas temperature in the output pipe 15.

[0047] The annular airbag 42 is coaxially fixed on the inner wall of the connecting tube 54 and is annular in shape. The annular airbag 42 contains air that expands due to heat. The annular airbag 42 has a larger deformation when the exhaust gas temperature is between B and C. At the same time, the thickness of the inner wall of the annular airbag 42 is the thinnest, so that when the annular airbag 42 is deformed, the inner wall is the first to be deformed; when the air temperature is between B and C, the exhaust gas contacts the annular airbag 42, so that the inner wall of the annular airbag 42 expands as the temperature rises, so that the inner diameter of the annular airbag 42 becomes smaller, that is, the blocking effect on the air becomes larger, and the air flow rate becomes slower; conversely, when the temperature decreases, the inner wall of the annular airbag 42 contracts, and the blocking effect on the air becomes smaller, so that the air flow rate becomes faster.

[0048] The reflux assembly 5 is arranged on the connecting pipe 54 and is connected with the input pipe 14. When the temperature detector 41 detects that the temperature is greater than C, the reflux assembly 5 starts to block the output pipe 15 and refluxes the air in the output pipe 15 to the input pipe 14. The reflux assembly 5 includes a reflux pipe 51 and a vent pipe 52. The reflux pipe 51 and the vent pipe 52 are connected with the connecting pipe 54 through a three-way valve 53. A one-way valve 55 is fixedly installed on the input pipe 14, and the reflux pipe 51 is connected with the one-way valve 55 away from the three-way valve 53. The one-way valve 55 only allows the exhaust gas in the reflux pipe 51 to enter the input pipe 14, and the vent pipe 52 is connected with the external environment.

[0049] A control valve for controlling the three-way valve 53 is fixedly installed on the connecting pipe 54 or the heat exchanger 12. The control valve is electrically connected to the temperature detector 41, so that the three-way valve 53 is controlled according to the temperature. A time relay is also provided on the connecting pipe 54 to adjust the control interval of the control valve, thereby reducing the probability of shortening the life of the control valve and the three-way valve 53 due to frequent control instructions of the control valve.

[0050] When the temperature is less than or equal to C, the control valve controls the three-way valve 53 so that the connecting pipe 54 is connected to the ventilation pipe 52, and the exhaust gas output by the output pipe 15 is discharged into the external environment through the connecting pipe 54 and the ventilation pipe 52 in turn. At this time, the exhaust gas flow rate is only regulated by the annular airbag 42; when the temperature is greater than C, the control valve controls the three-way valve 53 so that the connecting pipe 54 is connected to the return pipe 51, and the exhaust gas in the connecting pipe 54 flows back to the input pipe 14 through the return pipe 51 for heat exchange again, thereby greatly reducing the exhaust gas temperature output by the output pipe 15, so that the exhaust gas can achieve heat exchange with the dry air as much as possible, thereby achieving energy saving and reducing pollution to the environment.

[0051] The working principle of the embodiment of the present application is as follows: The air enters the condensation chamber 36 through the air inlet pipe 33 and exchanges heat with the condensing agent in the infusion pipe 32, so that the moisture in the air condenses and flows to the collection box 35 for collection, and then the air is output to the molecular sieve dryer 21 for further drying to form dry air, and the dry air enters the heat exchanger 12 through the inlet pipe 16, and the exhaust gas enters the heat exchanger 12 through the input pipe 14, so as to preheat the dry air. The preheated dry air enters the heater 13 for heating and then is input into the crystallizer 1 for drying, dehumidification and crystallization.

[0052] The exhaust gas enters the output pipe 15, and the temperature detector 41 detects the exhaust gas temperature. When the temperature is between B and C, the annular airbag 42 contacts the exhaust gas, so that the annular airbag 42 adjusts the blocking effect on the exhaust gas according to the temperature, so that the higher the exhaust gas temperature, the greater the blocking effect, so that the exhaust gas flow rate becomes slower, and finally the exhaust gas is discharged through the ventilation pipe 52; when the temperature is greater than C, the three-way valve 53 is started to connect the connecting pipe 54 with the return pipe 51, so that the exhaust gas in the connecting pipe 54 refluxes into the input pipe 14 for heat exchange again until the temperature drops below C. The three-way valve 53 controls the connecting pipe 54 to be connected with the ventilation pipe 52, so that the exhaust gas is discharged into the air, thereby further achieving energy saving and reducing pollution to the environment.

[0053] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A multi-stage high-efficiency dehumidification system for use in a VOC volatile environment, characterized by: The invention comprises an adsorption tower (11), a drying mechanism (2), a heat exchanger (12), and a heater (13); the adsorption tower (11) is used to adsorb VOC in the tail gas discharged from the crystallizer (1) and then input the adsorbed VOC into the heat exchanger (12); the drying mechanism (2) is used to dry the air and then input the air into the heat exchanger (12) to exchange heat with the tail gas and to preheat the air; and the heater (13) is used to heat the preheated air and then input the preheated air into the crystallizer (1).

2. A multi-stage high-efficiency dehumidification system for use in a VOC volatile environment according to claim 1, characterized in that: The drying mechanism (2) comprises: A condenser (3), used to condense the air to remove moisture; The molecular sieve dryer (21) is connected to the condenser (3) and the heat exchanger (12) and is used to dry the air after being processed by the condenser (3) and to input the dried air into the heat exchanger (12).

3. A multi-stage high-efficiency dehumidification system for use in a VOC volatile environment according to claim 2, characterized in that: The connection point between the molecular sieve dryer (21) and the adsorption tower (11) and the heat exchanger (12) is located on the same side of the heat exchanger (12), and the position where the air and the condensing agent enter the condenser (3) is located on the same side of the condenser (3).

4. The multi-stage high-efficiency dehumidification system for use in a VOC volatile environment according to claim 3, characterized in that: The heat exchanger (12) is provided with an input pipe (14) connected to the adsorption tower (11) and an output pipe (15) for outputting air. The input pipe (14) and the output pipe (15) are provided with a control mechanism (4). The control mechanism (4) detects that the exhaust gas temperature in the output pipe (15) is A. When B≤A<C, the control mechanism (4) controls the exhaust gas output speed in the output pipe (15) to gradually slow down as the temperature rises. When C≤A, the control mechanism (4) blocks the output pipe (15) and allows the air in the output pipe (15) to flow back into the input pipe (14) to continue heat exchange.

5. A multi-stage high-efficiency dehumidification system for use in a VOC volatile environment according to claim 4, characterized in that: The control mechanism (4) comprises: A temperature detector (41) is disposed in the output pipe (15) and is used to detect the exhaust gas temperature; An annular air bag (42) is arranged in the output pipe (15) and expands and contracts as the temperature rises and decreases after contacting the exhaust gas, so that the exhaust gas blocking effect gradually increases as the temperature rises; A reflux component (5) is arranged on the output pipe (15) and is connected to the input pipe (14). When the temperature detector (41) detects that the temperature is greater than C, the reflux component (5) starts to block the output pipe (15) and refluxes the air in the output pipe (15) into the input pipe (14).

6. The multi-stage high-efficiency dehumidification system for use in a VOC volatile environment according to claim 5, characterized in that: The reflux component (5) comprises: The return pipe (51) and the ventilation pipe (52) are connected to the output pipe (15) via a three-way valve (53); the three-way valve (53) is electrically connected to the temperature detector (41) and controls the output pipe (15) to be connected to the return pipe (51) or the ventilation pipe (52); one end of the return pipe (51) away from the output pipe (15) is connected to the input pipe (14) via a one-way valve (55); the one-way valve (55) allows the exhaust gas in the return pipe (51) to enter only the input pipe (14).

7. The multi-stage high-efficiency dehumidification system for use in a VOC volatile environment according to claim 6, characterized in that: The thickness of the inner side wall of the annular airbag (42) is the thinnest, and the inner side wall of the annular airbag (42) is deformed first.

8. The multi-stage high-efficiency dehumidification system for use in a VOC volatile environment according to claim 2, characterized in that: The condenser (3) comprises: A machine body (31) having a condensation chamber (36) formed therein; A liquid infusion tube (32) passing through the condensation chamber (36) and used for conveying a condensing agent; An air inlet pipe (33) and an air outlet pipe (34) are arranged on opposite side walls of the machine body (31) and are connected to the condensation chamber (36) and are used to input and output air respectively. The air in the condensation chamber (36) contacts the liquid infusion pipe (32) and is used to achieve condensation. A plurality of water-permeable micropores (37) are provided on the lower surface of the machine body (31) and are connected to the condensation chamber (36) and are used to allow water to penetrate. The collecting box (35) is arranged on the machine body (31) and is used to collect condensed water passing through the water-passing micropores (37).

9. The multi-stage high-efficiency dehumidification system for use in a VOC volatile environment according to claim 8, characterized in that: The infusion tube (32) located in the condensation chamber (36) is spiral-shaped and respectively forms a first chamber (38) and a second chamber (39) for air to pass through with the bottom and side wall of the condensation chamber (36).

10. The multi-stage high-efficiency dehumidification system for use in a VOC volatile environment according to claim 9, characterized in that: A smooth layer that facilitates heat transfer and the falling of water droplets is provided on the infusion tube (32) located in the condensation chamber (36).

Images