Ultralow water vapor partial pressure regeneration dryer system and control method thereof

Abstract

The invention provides an ultralow water vapor partial pressure regeneration dryer system and a control method thereof. The system comprises a gas inlet, a gas outlet, a first adsorption tower, a second adsorption tower, a heater, a deep drying assembly, a matched pipeline, a valve and a control system, the tower and the deep drying assembly are filled with adsorption filler, and adsorption and regeneration are achieved through a specific communication flow path. Part of the system is further provided with an air blower and a heat exchanger. The control method stipulates the working cycle steps of the adsorption tower according to different system configurations. According to the invention, the water vapor partial pressure of the regenerated gas can be effectively reduced, the efficient drying is realized through the optimized flow path design and the working method, all links can be accurately regulated and controlled through the control system, the application scene requirements with higher requirements on the gas drying degree are met, and the device has the advantages of low energy consumption, good drying effect and the like.

Description

Technical Field

[0001] The invention relates to the technical field of regenerative dryers, and in particular to an ultra-low water vapor partial pressure regenerative dryer system and a control method thereof. Background Art

[0002] In industrial production, many processes have extremely high requirements for the dryness of compressed gas, so adsorption dryers have become widely used drying equipment. Its core working principle is based on the adsorption of moisture in compressed gas by the adsorbent, thereby achieving the purpose of gas drying. The common double-tower adsorption dryer works alternately with two adsorption towers. When one tower is performing adsorption operation, the other tower is regenerating the adsorbent, thereby ensuring a continuous supply of dry compressed gas.

[0003] During the operation of the adsorption dryer, the regeneration effect of the adsorbent plays a decisive role in the overall performance of the dryer. The regeneration process mainly involves the hot air flow passing through the adsorbent, causing the water adsorbed in the adsorbent to evaporate and desorb, thereby restoring its adsorption capacity. Studies have shown that the water vapor partial pressure and regeneration temperature of the regeneration gas are key factors affecting the residual adsorption amount of the adsorbent regeneration. Specifically, the lower the water vapor partial pressure of the regeneration gas or the higher the regeneration temperature, the more thorough the desorption of the adsorbent, and the dryer can achieve a better drying effect, providing higher quality dry compressed gas for industrial production.

[0004] However, in order to reduce the amount of residual adsorption after adsorbent regeneration, most existing adsorption dryers use the method of increasing the regeneration temperature. Although this method can improve the drying effect to a certain extent, it brings serious energy consumption problems. Increasing the regeneration temperature requires a large amount of external heat or electricity to heat the regeneration gas. This not only greatly increases the production costs of enterprises, but also puts great pressure on energy supply and the environment. Especially in the current context of advocating energy conservation and emission reduction, this high-energy consumption drying method is increasingly difficult to meet the needs of sustainable development.

[0005] In order to solve the above problems, technicians in this field have been seeking more efficient and energy-saving adsorption dryer technical solutions. Some attempts focus on developing new adsorbents, but the research and development cycle of new adsorbents is long, the cost is high, and they may face compatibility problems in practical applications; others focus on optimizing the equipment structure, but the existing optimization solutions can often only reduce energy consumption to a limited extent and cannot fundamentally solve the problem of high energy consumption.

[0006] Therefore, developing a dryer system that can effectively reduce the residual adsorption of adsorbent regeneration without significantly increasing energy consumption or adjusting the regeneration temperature, and can stably output low dew point compressed gas, has become an important issue to be solved in the field of adsorption dryers. The ultra-low water vapor partial pressure regeneration dryer system and its control method proposed in the present invention are born in response to this background, aiming to fill the gap in the prior art and provide a more energy-saving and efficient drying solution for industrial production. Summary of the invention

[0007] The embodiments of the present invention provide an ultra-low water vapor partial pressure regeneration dryer system and a control method thereof, which aims to address the problems that existing adsorption dryers in the current technology mostly reduce the residual adsorption amount of adsorbent regeneration by increasing the regeneration temperature, resulting in a significant increase in system energy consumption, and there is currently no technical solution to effectively solve the high energy consumption problem.

[0008] The core technology of the present invention is to regenerate the filler in the adsorption tower under ultra-low water vapor partial pressure by secondary deep drying of part of the finished gas at the system outlet as regeneration gas, and optimize the system structure and process at the same time to achieve the purpose of reducing the residual adsorption amount of adsorbent regeneration, stably outputting low dew point compressed gas and saving energy.

[0009] In a first aspect, the present invention provides an ultra-low water vapor partial pressure regeneration dryer system, the system comprising: Inlet and exhaust ports for the entry and exit of gas; The first adsorption tower and the second adsorption tower are used cyclically and switched, and both are filled with fillers with moisture adsorption capacity; A heater, used for heating the gas; Deep drying components are filled with fillers with moisture adsorption capacity; Supporting pipelines, valves and control systems; Among them, there are also the following connecting flow paths: The air inlet, the first adsorption tower, and the exhaust port are sequentially connected to form an adsorption flow path 1; The air inlet, the second adsorption tower, and the exhaust port are sequentially connected to form an adsorption flow path 2; The exhaust port, the deep drying component, the heater, and the first adsorption tower are sequentially connected to form a heating regeneration flow path 1; The exhaust port, the deep drying component, the heater, and the second adsorption tower are sequentially connected to form a second heating regeneration flow path; The exhaust port, the heater, and the deep drying component are connected in sequence to form a heating regeneration flow path three.

[0010] Furthermore, it also includes a blower and a partition-type heat exchanger. The air outlet side of the blower is provided with a vacuum exhaust port. The blower, any adsorption tower and the high-temperature side of the heat exchanger constitute a circulating cold-blowing cooling flow path.

[0011] Furthermore, the maximum vacuum degree of the blower is not less than 30 kPa.

[0012] Furthermore, the low-temperature side of the heat exchanger is connected in series to the exhaust main pipe of the deep drying component, and the cold and hot media flow in the heat exchanger in reverse directions.

[0013] Furthermore, the fillers inside the first adsorption tower and the second adsorption tower are one or more of activated alumina, silica gel, silica-alumina gel or molecular sieve, and the filler inside the deep drying component is molecular sieve.

[0014] Furthermore, the packing weights of the first adsorption tower and the second adsorption tower are the same, and the packing weight of the deep drying assembly is 20-35% of the packing weight of the first adsorption tower or the second adsorption tower.

[0015] Furthermore, a self-operated flow regulating valve is provided at the exhaust port.

[0016] In a second aspect, the present invention provides a control method for an ultra-low water vapor partial pressure regeneration dryer system, wherein the working cycle of any adsorption tower comprises the following steps: Step S1: utilizing the characteristics of the packing in the tower to adsorb the moisture in the compressed gas; Step S2: releasing the pressure in the tower to make it the same as the ambient atmospheric pressure; Step S3: a preset amount of finished gas is further dehydrated by a deep drying component, and then heated by a heater before entering an adsorption tower, where the packing in the tower is regenerated and then discharged from the tower body; Step S4: allowing a preset amount of finished gas to enter the adsorption tower to remove heat from the packing in the tower; Step S5: allowing a preset amount of finished gas to enter the adsorption tower, and gradually increasing the pressure in the tower to the same as that of the other tower; Step S6: The adsorption tower waits to enter the next adsorption cycle, and at the same time, a preset amount of finished gas is heated by the heater to heat and regenerate the filler in the deep drying component.

[0017] In a third aspect, the present invention provides a control method for an ultra-low water vapor partial pressure regeneration dryer system, wherein the working cycle of any adsorption tower comprises the following steps: Step S1: utilizing the characteristics of the packing in the tower to adsorb the moisture in the compressed gas; Step S2: releasing the pressure in the tower to make it the same as the ambient atmospheric pressure; Step S3: a preset amount of finished gas is further dehumidified by a deep drying component, and then heated by a heater before entering an adsorption tower, where the packing in the tower is regenerated and then discharged from the tower; Step S4: extracting the gas in the tower by using a blower to reduce the pressure in the tower to -20 kPa (g), and then using the power provided by the blower to circulate heat exchange between the gas in the tower and the low-temperature medium in the heat exchanger, thereby gradually reducing the temperature of the packing in the tower; Step S5: allowing a preset amount of finished gas to enter the adsorption tower to further reduce the packing temperature in the tower; Step S6: allowing a preset amount of finished gas to enter the adsorption tower, and gradually increasing the pressure in the tower to the same as that of the other tower; Step S7: The adsorption tower waits to enter the next adsorption cycle, and at the same time, a preset amount of finished gas is heated by the heater to heat and regenerate the filler in the deep drying component.

[0018] Furthermore, during the circulating cooling process, when the difference between the outlet temperature of the high-temperature medium in the heat exchanger and the inlet temperature of the low-temperature medium is not higher than the first preset temperature, the circulating cooling is stopped and the next stage is entered; if when the circulating cooling is stopped, the difference between the temperature in the adsorption tower and the exhaust temperature of the system is not higher than the second preset temperature, step S5 is no longer executed.

[0019] The main contributions and innovations of the present invention are as follows: 1. Efficient drying: By setting up cyclically switched adsorption towers and deep drying components, and filling each tower and component with suitable adsorption fillers, the regenerated gas is deeply dried, which is significantly different from the existing multi-stage drying treatment, effectively reduces the gas water vapor partial pressure, and can meet the application scenarios with high requirements for gas dryness.

[0020] 2. Energy saving and consumption reduction: The system is equipped with a heat exchanger and a blower to recycle heat. Through the reverse flow of cold and hot media for heat exchange, efficient circulation and cooling can be achieved, reducing energy loss.

[0021] 3. Process optimization: clear and reasonable working cycle steps of the adsorption tower, such as adsorption, pressure release, regeneration, cooling and other links are carried out in an orderly manner, ensuring the continuous and stable operation of the system and improving the drying efficiency.

[0022] 4. Precise control: The equipped control system can accurately control and monitor the operating status of valves and equipment in real time, adjust various parameters according to system requirements, and ensure that the system is always operating in the best working conditions.

[0023] The details of one or more embodiments of the invention are set forth in the following drawings and description so that other features, objects, and advantages of the invention are more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 is a structural diagram of an ultra-low water vapor partial pressure regeneration dryer system according to an embodiment of the present invention; Figure 2 It is a structural diagram of an ultra-low water vapor partial pressure regeneration dryer system equipped with a blower according to an embodiment of the present invention.

[0025] In the figure, 1, air inlet; 2, exhaust port; T1, first adsorption tower; T2, second adsorption tower; T3, deep drying component; HR, heat exchanger; RB, blower; MF1, deep drying component exhaust silencer; MF2, T1 tower exhaust silencer; MF3, T2 tower exhaust silencer; V1, heating and cold blowing switching valve; V2, heating and regeneration air inlet valve; V3, deep drying flow regulating valve; V4, T2 tower finished gas exhaust valve; V5, T1 tower finished gas exhaust valve; V6, regeneration gas flow regulating valve; V7, T1 tower heating regeneration air inlet valve; V8, T2 tower heating regeneration air inlet valve; V9, circulating cooling main valve; V10, T1 tower regeneration gas exhaust valve; V11, T1 tower circulating cooling valve; V12, T2 tower circulating cooling valve; V13, T2 tower regeneration gas exhaust valve; V14, T1 tower adsorption air inlet valve; V15, T2 tower adsorption air inlet valve; V16, vacuum exhaust valve; V17, exhaust flow regulating valve; EH, heater. DETAILED DESCRIPTION

[0026] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with one or more embodiments of this specification. Instead, they are merely examples of devices and methods consistent with some aspects of one or more embodiments of this specification as detailed in the appended claims.

[0027] It should be noted that: in other embodiments, the steps of the corresponding method are not necessarily performed in the order shown and described in this specification. In some other embodiments, the steps included in the method may be more or less than those described in this specification. In addition, a single step described in this specification may be decomposed into multiple steps for description in other embodiments; and multiple steps described in this specification may be combined into a single step for description in other embodiments.

[0028] Existing adsorption dryers mostly reduce the residual adsorption amount of adsorbent regeneration by increasing the regeneration temperature, which leads to a significant increase in system energy consumption. At present, there is no effective technical solution to this high energy consumption problem.

[0029] Based on this, the present invention solves the problems existing in the prior art based on a new technical solution.

[0030] Embodiment 1 The present invention aims to propose an ultra-low water vapor partial pressure regeneration dryer system, specifically, referring to Figure 1 , the system comprising: The air inlet 1 and the air outlet 2 are used for the inlet and outlet of the gas; The first adsorption tower T1 and the second adsorption tower T2 are used cyclically and switched, and both are filled with fillers with moisture adsorption capacity; A heater EH, used for heating the gas; Deep drying component T3, which is filled with fillers with moisture adsorption capacity; Supporting pipelines, valves and control systems; Among them, there are also the following connecting flow paths: The air inlet 1, the first adsorption tower T1, and the exhaust port 2 are connected in sequence to form an adsorption flow path 1; The air inlet 1, the second adsorption tower T2, and the exhaust port 2 are connected in sequence to form an adsorption flow path 2; The exhaust port 2, the deep drying component T3, the heater EH, and the first adsorption tower T1 are sequentially connected to form a heating regeneration flow path 1; The exhaust port 2, the deep drying component T3, the heater EH, and the second adsorption tower T2 are sequentially connected to form a heating regeneration flow path 2; The exhaust port 2, the heater EH, and the deep drying component T3 are connected in sequence to form a heating regeneration flow path three.

[0031] In this embodiment, the fillers inside the first adsorption tower T1 and the second adsorption tower T2 are one or more of activated alumina, silica gel, silica-alumina gel or molecular sieve, and the fillers inside the deep drying component T3 are molecular sieves. Preferably, the weight of the fillers in the first adsorption tower T1 and the second adsorption tower T2 is the same, and the weight of the fillers in the deep drying component T3 is 20-35% of the weight of the fillers in the first adsorption tower T1 or the second adsorption tower T2 (because the deep drying component has too much fillers, its regeneration process will consume a lot of energy; too little fillers will make it difficult to further reduce the moisture content of the regenerated gas).

[0032] Specifically, molecular sieve is an excellent adsorbent. It has a larger specific surface area than alumina, and its surface pore size is very uniform, with good adsorption selectivity. Even when the water vapor partial pressure is very low, it still has a large adsorption capacity (activated alumina and silica gel only have a large adsorption capacity at high partial pressure). Therefore, molecular sieve is suitable for deep dehydration and drying of compressed air. The deep drying component uses molecular sieve as filler to further dehydrate and dry the compressed gas that has been adsorbed by the adsorption tower.

[0033] Preferably, if Figure 2As shown, the system also includes a blower RB and a partition heat exchanger HR. The blower RB is provided with a vacuum exhaust port V16 on the air outlet side. The blower RB, any adsorption tower and the high temperature side of the heat exchanger HR form a circulating cold blowing cooling flow path; the low temperature side of the heat exchanger HR is connected in series to the exhaust main pipe of the deep drying component T3, and the cold and hot media flow in the heat exchanger HR in reverse. The maximum vacuum degree of the blower RB is not less than 30kPa. Figure 2 exist Figure 1 On the basis of adding a blower and a heat exchanger, the process adds a circulating cooling process, and Figure 2 The solution replaces most (or all) of the finished product air cooling process with circulating cooling, which can reduce gas consumption and save energy.

[0034] In this embodiment, a self-operated flow regulating valve V17 is provided at the exhaust port 2 .

[0035] Among them, the self-operated flow regulating valve 17 automatically changes the resistance coefficient according to the changes in the system working conditions. Within a certain pressure difference range, it can effectively control the flow rate to maintain a constant value, that is, when the pressure difference before and after the valve increases, the automatic closing action of the valve can keep the flow rate from increasing. On the contrary, when the pressure difference decreases, the valve automatically opens and the flow rate remains constant. By installing a self-operated flow regulating valve at the exhaust port of the ultra-low water vapor partial pressure regeneration dryer system, the system load can be stabilized within the design working conditions. In addition, when multiple sets of ultra-low water vapor partial pressure regeneration dryer systems are used together in the main control system, the self-operated flow regulating valve can also play a role in evenly distributing the flow rate.

[0036] In order to facilitate the understanding of the scheme of this system, Table 1 is used for explanation: Table 1 Operation process and valve status table

[0037] When the first adsorption tower T1 or the second adsorption tower T2 of the system in Table 1 is in the adsorption state, the other tower sequentially completes several working steps such as pressure relief, heating regeneration, circulating cooling, finished gas cooling blowing, pressurization, and standby.

[0038] Specifically, each stage of the adsorption-regeneration process of any tower (taking the adsorption of the second adsorption tower T2 as an example): 1. Adsorption in the second adsorption tower T2. Adsorption process: The wet compressed gas enters from the air inlet 1, enters the second adsorption tower T2 through the T2 tower adsorption air inlet valve V15, the moisture in the wet compressed gas is adsorbed by the filler in the tower, and the dry compressed gas passes through the T2 tower finished gas exhaust valve V4 and enters the downstream gas use unit from the exhaust port 2.

[0039] 2. Pressure relief of the second adsorption tower T2. The compressed gas in the first adsorption tower T2 is discharged through the T2 tower regeneration gas exhaust valve V13 and the T2 tower exhaust muffler MF3.

[0040] 3. Heating and regenerating the second adsorption tower T2. A small amount of finished gas from the system exhaust main pipe enters the deep drying component through the heating and regeneration air intake valve V2 as regeneration gas. The moisture in the regeneration gas is further adsorbed by the filler in the deep drying component and then enters the heater. After being heated by the heater, the high-temperature regeneration gas passes through the heating and cold blowing switching valve V1, the regeneration gas flow regulating valve V6, and the T2 tower heating and regeneration air intake valve V8 in turn, and enters the second adsorption tower T2, heating the filler in the tower, and entrains the moisture separated from the filler through the T2 tower regeneration gas exhaust valve V13, and is discharged from the T2 tower exhaust silencer MF3.

[0041] 4. Circulation cooling of the second adsorption tower T2. The gas in the second adsorption tower T2, the heat exchanger HR and the circulation cooling pipeline is extracted by the blower and discharged by the vacuum exhaust valve V16 until the pressure in the second adsorption tower T2 drops below -20kPa (g). After the pressure reduction is completed, the vacuum exhaust valve V16 is closed, and the blower continues to transport low-pressure gas to circulate through the heat exchanger HR to exchange heat with the low-temperature fluid, so that the temperature of the packing in the second adsorption tower T2 is gradually reduced.

[0042] 5. Cold blowing of finished gas from the second adsorption tower T2. A small amount of finished gas from the system exhaust main pipe is used as cold blowing gas, which passes through the heating cold blowing switching valve V1, the regeneration gas flow regulating valve V6, and the T2 tower heating regeneration inlet valve V8 in sequence, enters the second adsorption tower T2, cools the packing in the tower, and passes through the T2 tower regeneration gas exhaust valve V13 and is discharged from the T2 tower exhaust silencer MF3.

[0043] 6. Pressure increase of the second adsorption tower T2. A small amount of finished gas from the system exhaust main pipe is used as cold blowing gas, which passes through the heating cold blowing switching valve V1, the regeneration gas flow regulating valve V6, and the T2 tower heating regeneration inlet valve V8 in sequence, and enters the second adsorption tower T2, and the pressure in the tower gradually increases.

[0044] 7. The second adsorption tower T2 is on standby. The second adsorption tower T2 maintains the working pressure and is ready to enter the next adsorption stage.

[0045] The following table shows the more specific operating process and valve status of this system:

[0046] The working principle of the blower RB of this system is to increase the pressure of air or gas through the movement of the rotor and the change of volume. The blower sucks gas through the inlet valve, and the rotor rotates to push the air or gas from the low-pressure end to the high-pressure end. The blower can both suck air and blow air, depending on its design and application.

[0047] Different types of blowers have different gas flow characteristics and pressure performance, and the negative pressure level at their inlets will also be different. The wind pressure of a single-stage centrifugal fan is usually between 3-10kPa, which is suitable for general gas delivery and ventilation scenarios. The wind pressure of a two-stage centrifugal fan is higher, reaching 20-45kPa; the wind pressure of a high-pressure blower is usually 15-70kPa.

[0048] The heat exchanger HR of this system is connected in series in the exhaust main pipe of the dryer. The use of finished gas to participate in the circulating cooling process can make the system do not need to provide low-temperature fluid externally, while improving the system integration and reducing the overall operating energy consumption. After the finished gas flows out from the first adsorption tower T1 through valve V5 and from the second adsorption tower T2 through valve V4, the subsequent confluence of this part of the pipeline leading to the exhaust port 2 can be regarded as the exhaust main pipe of the dryer. Its function is to collect and transport the dried gas to the exhaust port discharge system. At the same time, the low-temperature side of the heat exchanger HR is connected in series here to exchange heat with the high-temperature gas in the circulating cold blowing and cooling flow path.

[0049] The counter-current heat transfer of the heat exchanger HR means that the cold and hot fluids exchange heat in opposite directions in the heat exchanger. In the counter-current heat transfer, the temperature difference between the cold and hot fluids is the largest, so the maximum heat transfer effect can be achieved. At the same time, the counter-current heat transfer can avoid the problem of insufficient heat transfer caused by the temperature crossover point being too low or too high.

[0050] Embodiment 2 Based on the same concept, the present invention also proposes a control method for an ultra-low water vapor partial pressure regeneration dryer system, wherein the working cycle of any adsorption tower comprises the following steps: Step S1: utilizing the characteristics of the packing in the tower to adsorb the moisture in the compressed gas; Step S2: releasing the pressure in the tower to make it the same as the ambient atmospheric pressure; Step S3: a preset amount of finished gas is further dehumidified by the deep drying component T3, and then heated by the heater EH before entering the adsorption tower, where the packing in the tower is regenerated and then discharged from the tower body; Step S4: allowing a preset amount of finished gas to enter the adsorption tower to remove heat from the packing in the tower; Step S5: allowing a preset amount of finished gas to enter the adsorption tower, and gradually increasing the pressure in the tower to the same as that of the other tower; Step S6: the adsorption tower waits to enter the next adsorption cycle, and at the same time, a preset amount of finished gas is heated by the heater EH to heat and regenerate the filler in the deep drying component T3.

[0051] Embodiment 3 Based on the same concept, the present invention also proposes a control method for an ultra-low water vapor partial pressure regeneration dryer system, wherein the working cycle of any adsorption tower comprises the following steps: Step S1: utilizing the characteristics of the packing in the tower to adsorb the moisture in the compressed gas; Step S2: releasing the pressure in the tower to make it the same as the ambient atmospheric pressure; Step S3: The preset amount of finished gas is further dehumidified by the deep drying component T3, and then heated by the heater EH before entering the adsorption tower, where the packing in the tower is regenerated and then discharged from the tower body; Step S4: extracting the gas in the tower by using the blower RB to reduce the pressure in the tower to -20 kPa (g), and then using the power provided by the blower RB to circulate heat exchange between the gas in the tower and the low-temperature medium in the heat exchanger HR, thereby gradually reducing the temperature of the packing in the tower; Step S5: Allow a preset amount of finished gas to enter the adsorption tower to further reduce the temperature of the tower packing; the purpose of this step is to use the finished gas to directly reduce the tower packing temperature, but if the tower temperature is not significantly higher than the system exhaust port gas temperature at the end of the cycle cold blowing, there is no need to perform finished gas cold blowing, that is, step S5 is no longer executed.

[0052] Step S6: allowing a preset amount of finished gas to enter the adsorption tower, and gradually increasing the pressure in the tower to the same as that of the other tower; Step S7: the adsorption tower waits to enter the next adsorption cycle, and at the same time, a preset amount of finished gas is heated by the heater EH to heat and regenerate the filler in the deep drying component T3.

[0053] In this embodiment, during the circulating cooling process, when the difference between the outlet temperature of the high-temperature medium and the inlet temperature of the low-temperature medium in the heat exchanger HR is not higher than 5°C, the circulating cooling is stopped and the next stage is entered; if when the circulating cooling is stopped, the difference between the temperature in the adsorption tower and the temperature at the system exhaust port 2 is not higher than 3°C, step S5 is no longer executed.

[0054] Preferably, the cycle cooling time can be set to a fixed value, or it can be automatically controlled according to the actual operating status of the system. In the automatic control mode, it is preferred to use the packing temperature in the tower as a reference value. For example, the cycle cooling is stopped when the difference between the outlet temperature of the high-temperature medium and the inlet temperature of the low-temperature medium in the heat exchanger is not higher than 5°C. (If the difference is too high, the cooling target cannot be actually achieved; if the difference is too low, the economic efficiency of the system operation is affected).

[0055] Those skilled in the art should understand that the technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. Ultra-low water vapor partial pressure regeneration dryer system, characterized in that: include: An air inlet (1) and an air outlet (2) for the inlet and outlet of gas; The first adsorption tower (T1) and the second adsorption tower (T2) are used cyclically and switched, and are both filled with fillers with moisture adsorption capacity; A heater (EH), used to heat the gas; Deep drying component (T3), which is filled with fillers with moisture adsorption capacity; Supporting pipelines, valves and control systems; Among them, there are also the following connecting flow paths: The air inlet (1), the first adsorption tower (T1), and the exhaust port (2) are connected in sequence to form an adsorption flow path 1; The air inlet (1), the second adsorption tower (T2), and the exhaust port (2) are connected in sequence to form an adsorption flow path 2; The exhaust port (2), the deep drying component (T3), the heater (EH), and the first adsorption tower (T1) are connected in sequence to form a heating regeneration flow path 1; The exhaust port (2), the deep drying component (T3), the heater (EH), and the second adsorption tower (T2) are connected in sequence to form a second heating regeneration flow path; The exhaust port (2), the heater (EH), and the deep drying component (T3) are connected in sequence to form a heating regeneration flow path three.

2. The ultra-low water vapor partial pressure regeneration dryer system according to claim 1, characterized in that: It also includes a blower (RB) and a partition heat exchanger (HR), wherein the air outlet side of the blower (RB) is provided with a vacuum exhaust port (V16), and the blower (RB), any adsorption tower and the high-temperature side of the heat exchanger (HR) form a circulating cold-blowing cooling flow path.

3. The ultra-low water vapor partial pressure regeneration dryer system according to claim 2, characterized in that: The maximum vacuum degree of the blower (RB) is not less than 30 kPa.

4. The ultra-low water vapor partial pressure regeneration dryer system according to claim 2, characterized in that: The low temperature side of the heat exchanger (HR) is connected in series to the exhaust main pipe of the deep drying component (T3), and the cold and hot media flow in the heat exchanger (HR) in reverse directions.

5. The ultra-low water vapor partial pressure regeneration dryer system according to claim 1, characterized in that: The fillers inside the first adsorption tower (T1) and the second adsorption tower (T2) are one or more of activated alumina, silica gel, silica-alumina gel or molecular sieve, and the filler inside the deep drying component (T3) is molecular sieve.

6. The ultra-low water vapor partial pressure regeneration dryer system according to claim 1, characterized in that: The packing weights of the first adsorption tower (T1) and the second adsorption tower (T2) are the same, and the packing weight of the deep drying component (T3) is 20-35% of the packing weight of the first adsorption tower (T1) or the second adsorption tower (T2).

7. The ultra-low water vapor partial pressure regeneration dryer system according to any one of claims 1 to 6, characterized in that: A self-operated flow regulating valve (V17) is provided at the exhaust port (2).

8. The control method of the ultra-low water vapor partial pressure regeneration dryer system according to any one of claims 1 or 5-7, characterized in that: The working cycle of any adsorption tower includes the following steps: Step S1: utilizing the characteristics of the packing in the tower to adsorb the moisture in the compressed gas; Step S2: releasing the pressure in the tower to make it the same as the ambient atmospheric pressure; Step S3: a preset amount of finished gas is further dehydrated by a deep drying component (T3), and then heated by a heater (EH) before entering an adsorption tower to regenerate the packing in the tower and then discharged from the tower; Step S4: allowing a preset amount of finished gas to enter the adsorption tower to remove heat from the packing in the tower; Step S5: allowing a preset amount of finished gas to enter the adsorption tower, and gradually increasing the pressure in the tower to the same as that of the other tower; Step S6: The adsorption tower waits to enter the next adsorption cycle, and at the same time, a preset amount of finished gas is heated by the heater (EH) to heat and regenerate the filler in the deep drying component (T3).

9. The control method of the ultra-low water vapor partial pressure regeneration dryer system according to any one of claims 2 to 4, characterized in that: The working cycle of any adsorption tower includes the following steps: Step S1: utilizing the characteristics of the packing in the tower to adsorb the moisture in the compressed gas; Step S2: releasing the pressure in the tower to make it the same as the ambient atmospheric pressure; Step S3: a preset amount of finished gas is further dehydrated by a deep drying component (T3), and then heated by a heater (EH) before entering an adsorption tower to regenerate the packing in the tower before being discharged from the tower body; Step S4: extracting the gas in the tower by using a blower (RB) to reduce the pressure in the tower to -20 kPa (g), and then the blower (RB) provides power to circulate heat exchange between the gas in the tower and the low-temperature medium in the heat exchanger (HR), thereby gradually reducing the temperature of the packing in the tower; Step S5: allowing a preset amount of finished gas to enter the adsorption tower to further reduce the packing temperature in the tower; Step S6: allowing a preset amount of finished gas to enter the adsorption tower, and gradually increasing the pressure in the tower to the same as that of the other tower; Step S7: The adsorption tower waits to enter the next adsorption cycle, and at the same time, a preset amount of finished gas is heated by the heater (EH) to heat and regenerate the filler in the deep drying component (T3).

10. The control method according to claim 9, characterized in that: During the circulating cooling process, when the difference between the outlet temperature of the high-temperature medium in the heat exchanger (HR) and the inlet temperature of the low-temperature medium is not higher than the first preset temperature, the circulating cooling is stopped and the next stage is entered; if the difference between the temperature in the adsorption tower and the temperature at the system exhaust port (2) is not higher than the second preset temperature when the circulating cooling is stopped, step S5 is no longer executed.

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