Vacuum thermal desorption system of adsorption type drying machine

Abstract

The invention discloses a vacuum thermal desorption system of an adsorption type drying machine, and aims to solve the problem of high energy consumption when water needs to be removed in the process that an existing adsorption type drying machine utilizes heated air for desorption and the heated air performs water desorption on an adsorbent. The system comprises a controller, a vacuum adsorption dryer, a vacuum pump, a heater, an exhaust fan and the like. After compressed air enters the adsorption vacuum drier from the inlet, the humidity in the compressed air is adsorbed by the drying agent filled in the compressed air to reach the dew point of-65 DEG C, and the dried air is discharged from the outlet. In addition, according to the continuous alternating mode, when one tank carries out adsorption, the other tank carries out vacuum thermal desorption regeneration, when one tank carries out adsorption saturation, the vacuum thermal desorption regeneration process is carried out, meanwhile, the other tank is switched to carry out adsorption, and the switching operation of adsorption and desorption is not interrupted.

Description

Technical Field

[0001] The present invention relates to a vacuum thermal desorption system for an adsorption dryer, which is specifically used for dehumidifying the air compressed by an air compressor. It can not only achieve the purpose of drying the gas, but also reduce energy consumption. The present invention belongs to the technical field of adsorption desiccant drying. Background Art

[0002] There is moisture in the air. After the air is compressed by an air compressor, it contains a certain amount of moisture. If it is not subjected to adsorption drying treatment, when these high-pressure gases are used in the process, the products will have problems such as abnormal yield due to moisture residue.

[0003] In the existing air dryer technology, hot air after heating is used to heat the adsorbent to evaporate the moisture in the adsorbent. To remove the moisture, hot air needs to be used to heat the desiccant in the adsorption dryer, and the equipment operation cost is extremely high. Due to the limitations of the structure and process of some adsorption drying devices, the temperature of the desiccant is high and then needs to be cooled down to 25°C, resulting in high energy consumption in the whole treatment process, which greatly affects the industrial operation cost.

[0004] Chinese Patent CN109883215A discloses a twin-tower adsorption dryer, but only atmospheric hot air circulation is adopted in its desorption stage, and the vacuum environment is not combined to enhance the desorption efficiency; although US Patent US9567543B2 proposes vacuum-assisted regeneration, it lacks the valve coordination control logic during the switching of the twin towers, and it is easy to cause airflow impact and damage the valve body seal.

[0005] Therefore, researching and developing an adsorption dryer vacuum thermal desorption system with high efficiency, energy saving, and continuous operation is of crucial practical significance for improving the drying treatment of compressed air and achieving energy saving. Summary of the Invention

[0006] The purpose of the present invention is to provide an adsorption dryer vacuum thermal desorption system.

[0007] The present invention provides an adsorption dryer vacuum thermal desorption system, comprising: a controller, a first adsorption vacuum dryer, a desiccant, a first inlet valve, a first outlet valve, a first hot air inlet valve, a first hot air outlet valve, an exhaust fan, a first vacuum valve and a vacuum pump. The first adsorption vacuum dryer is connected to and controlled by the controller. The desiccant is filled inside the first adsorption vacuum dryer. The first inlet valve is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer. The first inlet valve is used to introduce a compressed air to be dried into the first adsorption vacuum dryer, and the moisture is absorbed by the desiccant. The first outlet valve is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer. The first outlet valve is used to export the purified compressed air for use in the subsequent process. The first hot air inlet valve is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer. The first hot air inlet valve is connected to a heater and is used to supply heat. The first hot air outlet valve is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer. The exhaust fan is connected to and controlled by the controller and is connected to the heater. The exhaust fan transports the air heated by the heater through air flow and enters the first adsorption vacuum dryer through the first hot air inlet valve to desorb the adsorption-saturated desiccant. The first vacuum valve is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer. The vacuum pump is connected to and controlled by the controller and is connected to the first vacuum valve. The vacuum pump is used to evacuate the first adsorption vacuum dryer so that the required vacuum degree is achieved inside the tower of the first adsorption vacuum dryer.

[0008] In an embodiment of the present invention, after the desiccant in the first adsorption vacuum dryer is saturated with adsorption, all valves corresponding to the first adsorption vacuum dryer are closed, and at the same time, the first vacuum valve and the vacuum pump are opened to evacuate, and at the same time, the first hot air inlet valve is opened to supply heat source for desorption.

[0009] In an embodiment of the present invention, the dryer vacuum thermal desorption system further includes a second adsorption vacuum dryer, a second intake valve, a second outlet valve, a second hot air intake valve, a second hot air outlet valve, and a second vacuum valve. The second adsorption vacuum dryer is connected to and controlled by the controller, and the desiccant is filled inside the second adsorption vacuum dryer. The second intake valve is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer. The second intake valve is used to introduce the compressed air to be dried into the second adsorption vacuum dryer, and the moisture is absorbed by the desiccant. The second outlet valve is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer. The second outlet valve is used to export the purified compressed air for use in the subsequent process. The second hot air intake valve is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer. The second hot air intake valve is connected to the heater and is used to supply heat. The second hot air outlet valve is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer. The second vacuum valve is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer. The vacuum pump is connected between the first vacuum valve and the second vacuum valve and is connected to and controlled by the controller. The vacuum pump is used to evacuate the second adsorption vacuum dryer so that the required vacuum degree is achieved inside the tower of the second adsorption vacuum dryer.

[0010] In an embodiment of the present invention, after the desiccant in the second adsorption vacuum dryer is saturated with adsorption, all the valves corresponding to the second adsorption vacuum dryer are closed, and at the same time, the second vacuum valve and the vacuum pump are opened for evacuation, and at the same time, the second hot air intake valve is opened to supply heat source for desorption.

[0011] In an embodiment of the present invention, while the second adsorption vacuum dryer is performing the desorption process, the compressed air to be dried is introduced into the first adsorption vacuum dryer by the controller for adsorption operation, and the controller controls the switching of adsorption and desorption between the two towers to be carried out simultaneously and cyclically to achieve continuous adsorption and desorption.

[0012] In an embodiment of the present invention, the adsorption dryer vacuum thermal desorption system further includes a pressure regulating device. The pressure regulating device has two ends respectively connected to the second vacuum valve and the vacuum pump. The pressure regulating device is used to cooperate with the vacuum pump to adjust the vacuum degrees inside the first adsorption vacuum dryer and the second adsorption vacuum dryer, change the internal pressure and boiling point, so that the water vapor is more easily evaporated and energy is saved.

[0013] In an embodiment of the present invention, the desiccant is filled inside the adsorption vacuum dryer with an adsorbent having a strong water-binding ability, such as molecular sieve, activated alumina, or silica gel.

[0014] In summary, the vacuum thermal desorption system of the adsorption dryer disclosed by the present invention can bring the following effects:

[0015] 1. Energy saving and consumption reduction: The system of the present invention adopts vacuum thermal desorption technology, reduces the desorption temperature, and effectively reduces energy consumption. In addition, the application of the pressure regulating device further improves the desorption efficiency and reduces the operating cost of the system.

[0016] 2. Continuous operation: The system realizes continuous regeneration and recycling of the desiccant by setting two vacuum dryers and switching and circulating between the two towers, ensuring continuous adsorption and desorption operations of the system. This not only improves the processing efficiency but also minimizes the impact on production.

[0017] 3. Precise control: The controller can precisely control the operating parameters of each device, such as temperature, pressure, flow rate, etc. Through real-time monitoring and adjustment, it ensures that the system always operates under the best conditions, improving the stability and reliability of the compressed air drying process.

[0018] The following will be described in detail through specific embodiments, and it should be easier to understand the purpose, technical content, characteristics, and achieved effects of the present invention. Brief Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the vacuum thermal desorption system of the adsorption dryer of the present invention.

[0020] Description of the reference numerals in the drawings: 100 - vacuum thermal desorption system of the adsorption dryer; 101 - controller; 102 - first adsorption vacuum dryer; 103 - first intake valve; 104 - first hot air intake valve; 105 - first hot air outlet valve; 106 - first outlet valve; 107 - first vacuum valve; 108 - second adsorption vacuum dryer; 109 - second intake valve; 110 - second hot air intake valve; 111 - second hot air outlet valve; 112 - second outlet valve; 113 - second vacuum valve; 114 - pressure regulating device; 115 - vacuum pump; 116 - exhaust fan; 117 - heater; DS - desiccant; CDA - compressed air. Detailed Description of the Embodiment

[0021] Under the prior art, the drying process of compressed air mostly involves: using an adsorbent with strong water-binding ability to forcibly absorb the moisture in the air compressed by an air compressor to achieve the purpose of drying the air, and then directly using heated hot air for dehydration to evaporate the moisture. The present invention uniquely uses an efficient drying and adsorption device and then continues with vacuum heating for desorption. Due to the principle of vacuum, the boiling point is reduced, so high-temperature desorption is not required, achieving energy conservation and carbon reduction. Under the prior art, directly using hot air to evaporate moisture results in extremely high equipment costs and operating costs.

[0022] Please refer to Figure 1 as shown Figure 1 which is a schematic diagram of the vacuum thermal desorption system of the adsorption dryer of the present invention. As shown in the figure, the vacuum thermal desorption system 100 of the adsorption dryer includes a controller 101, a first adsorption vacuum dryer 102, a first intake valve 103, a first hot air intake valve 104, a first hot air outlet valve 105, a first outlet valve 106, and a first vacuum valve 107. The first adsorption vacuum dryer 102 is connected to and controlled by the controller 101. A desiccant DS is filled inside the first adsorption vacuum dryer 102, and the desiccant DS is an adsorbent with strong water-binding ability such as molecular sieve, activated alumina or silica gel. The first intake valve 103 is connected to and controlled by the controller 101 and is connected to the first adsorption vacuum dryer 102. The first intake valve 103 is used to introduce compressed air CDA to be dried into the first adsorption vacuum dryer 102 and the moisture is absorbed by the desiccant DS. The first outlet valve 106 is connected to and controlled by the controller 101 and is connected to the first adsorption vacuum dryer 102. The first outlet valve 106 is used to export the purified and dried compressed air CDA for use in the subsequent process. The first hot air intake valve 104 is connected to and controlled by the controller 101 and is connected to the first adsorption vacuum dryer 102. The first hot air intake valve 104 is connected to a heater 117 and is used to supply heat. The first hot air outlet valve 105 is connected to and controlled by the controller 101 and is connected to the first adsorption vacuum dryer 102. An exhaust fan 116 is connected to and controlled by the controller 101 and is connected to the heater 117. The air heated by the heater 117 transported by the exhaust fan 116 enters the first adsorption vacuum dryer 102 through the first hot air intake valve 104 to desorb the adsorption-saturated desiccant DS. The first vacuum valve 107 is connected to and controlled by the controller 101 and is connected to the first adsorption vacuum dryer 102. A vacuum pump 115 is connected to and controlled by the controller 101 and is connected to the first vacuum valve 107. The vacuum pump 115 is used to pump air from the first adsorption vacuum dryer 102 to make the required vacuum degree reached inside the tower of the first adsorption vacuum dryer 102. After the desiccant DS in the first adsorption vacuum dryer 102 is adsorbed saturated, all valves corresponding to the first adsorption vacuum dryer 102 are closed and at the same time the first vacuum valve 107 and the vacuum pump 115 are opened to pump air, and at the same time heat source is supplied through the first hot air intake valve 104 for desorption.

[0023] The adsorption dryer vacuum thermal desorption system 100 further includes a second adsorption vacuum dryer 108, a second intake valve 109, a second hot air intake valve 110, a second hot air outlet valve 111 and a second vacuum valve 113. The second adsorption vacuum dryer 108 is connected to and controlled by the controller 101, wherein a desiccant DS is filled inside the second adsorption vacuum dryer 108, and the desiccant DS is an adsorbent with strong water adsorption ability such as molecular sieve, activated alumina or silica gel. The second intake valve 109 is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer 108. The second intake valve 109 is used to introduce compressed air CDA to be dried into the second adsorption vacuum dryer 108 and the moisture is absorbed by the desiccant DS. The second outlet valve 112 is connected to and controlled by the controller 101 and is connected to the second adsorption vacuum dryer 108. The second outlet valve 112 is used to export the purified and dried compressed air CDA for use in the subsequent process. The second hot air intake valve 110 is connected to and controlled by the controller 101 and is connected to the second adsorption vacuum dryer 108. The second hot air intake valve 110 is connected to a heater and is used to supply heat. The second hot air outlet valve 111 is connected to and controlled by the controller 101 and is connected to the second adsorption vacuum dryer 108. The exhaust fan 116 is connected to and controlled by the controller 101 and is connected to the heater 117. The exhaust fan 116 transports the air heated by the heater 117 through the air flow and enters the second adsorption vacuum dryer 108 through the second hot air intake valve 110 to desorb the adsorption-saturated desiccant DS. The second vacuum valve 113 is connected to and controlled by the controller 101 and is connected to the second adsorption vacuum dryer 108. The vacuum pump 115 is connected between the first vacuum valve 107 and the second vacuum valve 113 and is connected to and controlled by the controller 101. The vacuum pump 115 is used to evacuate the second adsorption vacuum dryer 108 to make the inside of the tower of the second adsorption vacuum dryer 108 reach the required vacuum degree. After the desiccant DS in the second adsorption vacuum dryer 108 is saturated with adsorption, all valves corresponding to the second adsorption vacuum dryer 108 are closed and at the same time the second vacuum valve 113 and the vacuum pump 115 are opened to evacuate, and at the same time heat source is supplied through the second hot air intake valve 110 for desorption.

[0024] In other words, when the second adsorption vacuum dryer 108 is performing the desorption process, the compressed air CDA to be dried is introduced into the first adsorption vacuum dryer 102 by the controller 101 for adsorption operation, and the controller 101 controls the switching between adsorption and desorption between the two towers to be carried out simultaneously and cyclically to achieve continuous adsorption and desorption.

[0025] It is worth mentioning that the vacuum thermal desorption system 100 of the adsorption dryer further includes a pressure regulating device 114. Both ends of the pressure regulating device 114 are respectively connected to the second vacuum valve 113 and the vacuum pump 115. The pressure regulating device 114 is used to cooperate with the vacuum pump 115 to adjust the vacuum degree in the first adsorption vacuum dryer 102 and the second adsorption vacuum dryer 108 and change the internal atmospheric pressure so that water vapor is more likely to evaporate and energy is saved.

[0026] In the present invention, the vacuum thermal desorption system 100 of the adsorption dryer is designed to process the air compressed by the air compressor. Through steps such as adsorption and vacuum thermal desorption, the dual goals of compressed air drying and energy conservation and carbon reduction are achieved. The following elaborates on its operating principle in detail from the single-tower and double-tower modes.

[0027] [Operating principle of single-tower mode]

[0028] Adsorption stage: During the industrial production process, the compressed air CDA used is guided through a pipeline to the first adsorption vacuum dryer 102. The compressed air CDA comes into full contact with the desiccant DS filled in the first adsorption vacuum dryer 102, and the moisture in the compressed air CDA is adsorbed by the desiccant DS, realizing the preliminary purification and adsorption of the water vapor in the compressed air CDA.

[0029] Desorption stage: As the adsorption process continues, the desiccant DS gradually reaches the adsorption saturation state. At this time, the controller 101 receives the saturation signal of the desiccant DS from the first adsorption vacuum dryer 102, and then correspondingly issues an instruction to close all the valves corresponding to the first adsorption vacuum dryer 102 to ensure the tightness of the system. Then the first vacuum valve 107 is opened, and at the same time, the vacuum pump 115 is started to pump air to reduce the pressure in the tower. At the same time, the controller 101 controls the first hot air inlet valve 104 to open and connect to the heater 117 to supply heat source for desorption. Under the dual action of vacuum and heating, the water vapor obtains sufficient heat energy and evaporates from the desiccant DS.

[0030] Desiccant regeneration stage: When the desorption process is completed, the desiccant DS in the adsorption vacuum dryer restores its adsorption activity. At this time, the controller 101 controls the first inlet valve 103 to open, and the compressed air CDA to be dried enters the first adsorption vacuum dryer 102 to break the vacuum state in the first adsorption vacuum dryer 102. Subsequently, it participates in the adsorption process again to realize the recycling of the adsorbent.

[0031] [Operating principle of double-tower mode]

[0032] The first tower adsorbs and the second tower desorbs: After the first adsorption vacuum dryer 102 completes the vacuum thermal desorption operation, its corresponding valves are closed under the control of the controller 101. The first intake valve 103 is opened under the instruction of the controller 101 to send compressed air CDA into the first adsorption vacuum dryer 102 to continue the adsorption operation. The controller 101 closes all the valves connected to the second adsorption vacuum dryer 108, opens the second vacuum valve 113, and starts the vacuum pump 115 to evacuate the second adsorption vacuum dryer 108. At the same time, the controller 101 controls the second hot air intake valve 110 to open, introducing the high-temperature gas heated by the heater 117 to perform the vacuum thermal desorption operation in the second adsorption vacuum dryer 108.

[0033] The first tower desorbs and the second tower adsorbs: After the second adsorption vacuum dryer 108 completes the vacuum thermal desorption operation, its corresponding valves are closed under the control of the controller 101. The second intake valve 109 is opened under the instruction of the controller 101 to send compressed air CDA into the second adsorption vacuum dryer 108 to continue the adsorption operation. The controller 101 closes all the valves connected to the first adsorption vacuum dryer 102, opens the first vacuum valve 107, and starts the vacuum pump 115 to evacuate the first adsorption vacuum dryer 102. At the same time, the controller 101 controls the first hot air intake valve 104 to open, introducing the high-temperature gas heated by the heater 117 to perform the vacuum thermal desorption operation in the first adsorption vacuum dryer 102. Repeat the above adsorption and desiccant DS desorption regeneration process to realize the switching cycle between the first adsorption vacuum dryer 102 and the second adsorption vacuum dryer 108, thereby ensuring the continuous operation of the system and greatly improving the drying efficiency of the compressed air CDA.

[0034] [Auxiliary working principle of pressure regulating device]

[0035] The pressure regulating device 114 works together with the vacuum pump 115 and the first vacuum valve 107 (or the second vacuum valve 113). During the thermal desorption process, the pressure regulating device 114 monitors the pressure changes in the first adsorption vacuum dryer 102 and the second adsorption vacuum dryer 108 in real time, and fine-tunes the pressure inside the tower according to the preset pressure range. By precisely controlling the pressure inside the tower, the boiling point is reduced, promoting the easier desorption of water vapor, further improving the desorption efficiency, and reducing the system energy consumption.

[0036] In the present invention, the water vapor adsorbed in the desiccant DS continuously adjusts the vacuum degree in the first adsorption vacuum dryer 102 and the second adsorption vacuum dryer 108, that is, by changing the internal atmospheric pressure to lower the boiling point, so that the water vapor in the desiccant DS is desorbed in the shortest time and the most energy-saving way.

[0037] Briefly speaking, in the prior art, desorption is carried out under a stable low-high pressure state in a dryer, and the hot air must be heated to a temperature of 160 degrees Celsius to evaporate water vapor. In the present invention, by combining the use of a vacuum pump 115 and a pressure regulating device 114, the pressure in the first adsorption vacuum dryer 102 or the second adsorption vacuum dryer 108 is in a vacuum state, reducing the boiling point and making it easier for water vapor to evaporate from the desiccant DS, resulting in better drying effect.

[0038] The following will describe a specific embodiment, and the following data is only one of the preferred embodiments.

[0039] I. Adsorption stage (taking the first tower as an example)

[0040] Air flow path: The compressed air CDA to be dried passes through a filter (not shown in the figure) to remove particulate impurities, and then the first intake valve 103 is opened by the controller 101 and enters the first adsorption vacuum dryer 102 at a pressure of 0.6 - 1.0 MPa. The air flows upward from the bottom of the tower. When passing through the molecular sieve bed layer, the moisture is trapped by the adsorbent, and the dried compressed air CDA is transported to the subsequent process through the first outlet valve (106). At this time, the second adsorption vacuum dryer 108 synchronously performs desorption.

[0041] Key parameters: Adsorption air flow rate: 5 - 50 m 3 / min (adjusted according to the tower body specifications); Bed layer flow velocity: 0.1 - 0.3 m / s (ensuring gas-solid contact time ≥ 2 seconds).

[0042] II. Desorption stage (taking the regeneration after the first tower is saturated as an example)

[0043] Pretreatment stage (0 - 2 minutes): When the controller 101 detects that the outlet dew point of the first adsorption vacuum dryer 102 rises to -30 °C, a switching instruction is issued: close the first intake valve 103 and the first outlet valve 106, and at the same time open the second intake valve 109 and the second outlet valve 112 of the second adsorption vacuum dryer 108, and introduce the compressed air CDA to be dried into the second adsorption vacuum dryer 108 for continued adsorption.

[0044] Vacuum establishment stage (2 - 12 minutes): Open the first vacuum valve 107 and the vacuum pump 115, and the pressure regulating device 114 fully opens the bypass valve, so that the pressure in the tower drops from atmospheric pressure to -80 kPa within 5 minutes, avoiding the adsorbent from cracking due to a sudden drop in pressure.

[0045] Thermal desorption stage (12 - 42 minutes): The exhaust fan 116 is started, and ambient air or recycled gas is sent into the heater 117 and heated to 180 ± 5 °C. Then it is purged downward from the top of the tower through the first hot air inlet valve 104 to the molecular sieve bed layer, and the desorbed water vapor is discharged through the first hot air outlet valve 105 to the condensation recovery device (not shown in the figure). The pressure regulating device 114 gradually closes the bypass valve to stably maintain the vacuum degree at -90 kPa. At this stage, the water evaporation rate is increased to 3 times that in the atmospheric environment.

[0046] Cooling and resetting stage (42 - 50 minutes): The heater 117 is turned off, and the vacuum pump 115 continues to operate. The adsorption tower is cooled to below 40 °C using room temperature gas, and then all desorption valves are closed, waiting for the next adsorption instruction.

[0047] III. Twin - tower switching logic

[0048] Time - priority mode: Set a fixed switching interval (such as 120 minutes), which is applicable to stable operating conditions. Dew - point - priority mode: Real - time monitor the outlet dew point, and trigger the switch immediately when it exceeds - 30 °C, which is applicable to occasions with large fluctuations in wet load. During the switching process, the controller 101 executes the "close first, then open" logic: First, close all inlet and outlet valves of the tower to be switched, and then open the corresponding desorption / adsorption valves after a 2 - second delay to prevent air flow from cross - flowing between towers.

[0049] In terms of expanded performance, the vacuum thermal desorption system of the adsorption dryer disclosed in the present invention can be expanded from the above - mentioned two adsorption vacuum dryers to three, four, or even more adsorption vacuum dryers. The operation mechanisms of three or more towers can be understood by referring to the operation mechanisms of the single - tower and twin - tower described above, and will not be elaborated here.

[0050] In summary, the vacuum thermal desorption system of the adsorption dryer disclosed in the present invention can bring the following effects:

[0051] 1. Energy conservation and consumption reduction: The system of the present invention adopts vacuum thermal desorption technology, reduces the desorption temperature, and effectively reduces energy consumption. In addition, the application of the pressure regulating device further improves the desorption efficiency and reduces the operating cost of the system.

[0052] 2. Continuous operation: The system sets two vacuum dryers and switches and circulates between the two towers, realizing continuous regeneration and recycling of the desiccant, ensuring continuous adsorption and desorption operations of the system. This not only improves the processing efficiency but also minimizes the impact on production.

[0053] 3. Precise control: The controller can precisely control the operating parameters of each device, such as temperature, pressure, flow rate, etc. Through real - time monitoring and adjustment, it ensures that the system always operates under the best conditions, improving the stability and reliability of compressed air drying treatment.

[0054] The above are only the preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Therefore, all equivalent changes or modifications made according to the features and spirit described in the claims of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. An adsorption dryer vacuum thermal desorption system, characterized in that: Comprising: A controller; A first adsorption vacuum dryer, which is connected to and controlled by the controller; A desiccant, which is filled inside the first adsorption vacuum dryer; A first intake valve, which is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer. The first intake valve is used to introduce a compressed air to be dried into the first adsorption vacuum dryer and the moisture is absorbed by the desiccant; A first outlet valve, which is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer. The first outlet valve is used to export the purified compressed air for use in the subsequent process; A first hot air intake valve, which is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer. The first hot air intake valve is connected to a heater and is used to supply heat; A first hot air outlet valve, which is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer; An exhaust fan, which is connected to and controlled by the controller and is connected to the heater. The exhaust fan transports the air heated by the heater through the air flow to enter the first adsorption vacuum dryer through the first hot air intake valve to desorb the adsorption-saturated desiccant; A first vacuum valve, which is connected to and controlled by the controller and is connected to the first adsorption vacuum dryer; And A vacuum pump, which is connected to and controlled by the controller and is connected to the first vacuum valve. The vacuum pump is used to evacuate the first adsorption vacuum dryer so that the required vacuum degree is achieved inside the tower of the first adsorption vacuum dryer.

2. The vacuum thermal desorption system of the adsorption dryer according to claim 1, characterized in that: After the desiccant in the first adsorption vacuum dryer is saturated in adsorption, all the valves corresponding to the first adsorption vacuum dryer are closed and at the same time the first vacuum valve and the vacuum pump are opened to evacuate the air, and at the same time the first hot air intake valve is opened to supply heat source for desorption.

3. The vacuum thermal desorption system of the adsorption dryer according to claim 2, wherein: Further comprising: A second adsorption vacuum dryer, which is connected to and controlled by the controller, wherein the desiccant is filled inside the second adsorption vacuum dryer; A second intake valve, which is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer. The second intake valve is used to introduce the compressed air to be dried into the second adsorption vacuum dryer and the moisture is absorbed by the desiccant; A second outlet valve, which is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer. The second outlet valve is used to export the purified compressed air for use in the subsequent process; A second hot air intake valve, which is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer. The second hot air intake valve is connected to the heater and is used to supply heat; A second hot air outlet valve, which is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer; and A second vacuum valve, which is connected to and controlled by the controller and is connected to the second adsorption vacuum dryer, The vacuum pump is connected between the first vacuum valve and the second vacuum valve and is connected to and controlled by the controller. The vacuum pump is used to evacuate the second adsorption-type vacuum dryer so as to achieve the required vacuum degree inside the tower of the second adsorption-type vacuum dryer.

4. The vacuum thermal desorption system of the adsorption dryer according to claim 3, wherein: After the desiccant in the second adsorption-type vacuum dryer is saturated with adsorbed water, all valves corresponding to the second adsorption-type vacuum dryer are closed, and at the same time, the second vacuum valve and the vacuum pump are opened to evacuate the air, and at the same time, heat source is supplied for desorption by opening the second hot air inlet valve.

5. The vacuum thermal desorption system of the adsorption dryer according to claim 4, characterized in that: When the second adsorption-type vacuum dryer is performing the desorption procedure, the compressed air to be dried is introduced into the first adsorption-type vacuum dryer by the controller for adsorption operation, and the controller controls the switching between adsorption and desorption to be carried out simultaneously and cyclically between the two towers so as to achieve continuous adsorption and desorption.

6. The vacuum thermal desorption system of the adsorption dryer according to claim 1, characterized in that: Further comprising: A pressure regulating device, the two ends of which are respectively connected to the second vacuum valve and the vacuum pump. The pressure regulating device is used to cooperate with the vacuum pump to adjust the vacuum degree inside the first adsorption-type vacuum dryer and the second adsorption-type vacuum dryer, change the internal pressure and boiling point so that water vapor is more easily evaporated and energy is saved.

7. The vacuum thermal desorption system of the adsorption dryer according to claim 1, characterized in that: The desiccant is filled inside the adsorption-type vacuum dryer with an adsorbent having a strong water-binding ability, such as molecular sieve, activated alumina or silica gel.

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