Automatic control method and control system for reducing gas loss of adsorption dryer

Abstract

The invention discloses an automatic control method and system for reducing gas loss of an adsorption dryer, and the automatic control method comprises the steps: employing a periodic time control mode for operation at the initial operation stage of the adsorption dryer; an adaptive control mode is adopted for operation; the actual regeneration time is adjusted until Td set + Td floating low < = Td actual < = Td set + Td floating high; and when the real-time dew point value Td actual is adjusted to a range of Td set + Td floating low < = Td actual < = Td set + Td floating high, obtaining regeneration time t regeneration and fixed adsorption time t adsorption executed in each period. In the self-adaptive control mode, the time of the adsorption process and the regeneration process is automatically adjusted, so that the dew point value is always within the set tolerance range, the gas loss of the adsorption dryer is always kept in the lowest state, the adsorbent is fully utilized, and the power consumption and the maintenance cost of the whole machine are reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of adsorption dryers, and particularly relates to an automatic control method and a control system for reducing the gas loss of an adsorption dryer. BACKGROUND

[0002] The dew point is a key indicator of medical and instrument compressed air, and the adsorption dryer is one of the key devices for realizing the required dew point. The performance indicators of the adsorption dryer mainly include the compressed air processing amount, the gas loss, and the dew point value. The gas loss of the adsorption dryer is mainly determined by the size of the regeneration path, the regeneration time, and the adsorption pressure. The larger the pressure, the larger the path, and the longer the regeneration time, the larger the gas loss. However, the dew point value will not decrease indefinitely due to the increase of the gas loss, which depends on the performance of the adsorbent and the regeneration effect. The user end sets the compressed air pressure according to the actual use requirements, and the pressure is high or low, and the gas loss also changes. In the case that the regeneration path and the regeneration time are uncontrollable, the larger the pressure, the larger the regeneration path, and the larger the regeneration flow, which causes a large amount of dry air meeting the required dew point to be used for regeneration (the regeneration gas is too much, and the actual regeneration gas does not need to be so much), resulting in an increase in the gas loss; and the smaller the required pressure, the smaller the regeneration path, and the smaller the regeneration flow, which may cause insufficient regeneration flow, and the water in the adsorbent is not fully removed, and after multiple alternating cycles, the dew point value does not meet the requirements.

[0003] In the above case, the gas loss is difficult to effectively control, causing waste of compressed air, the dew point value being higher than the required value for a long time, increasing the equipment running time, shortening the service life of the adsorbent, and increasing the power consumption and maintenance cost.

[0004] In view of this, the present application is proposed. SUMMARY

[0005] In order to solve the technical problems of the existing adsorption dryer that the gas loss is difficult to effectively control, causing waste of compressed air, increasing the equipment running time, and shortening the service life of the adsorbent, the present application provides an automatic control method and a control system for reducing the gas loss of an adsorption dryer.

[0006] The present application adopts the following technical solutions: The first object of the present application is to provide an automatic control method for reducing the gas loss of an adsorption dryer, comprising: In the initial stage of the operation of the adsorption dryer, a periodic time control mode is adopted for operation; After the operation of the periodic time control mode is completed, an adaptive control mode is adopted for operation; In the adaptive control mode: (1) comparing the measured real-time dew point value Td 实 with the dew point set value Td设 , if Td 实 > Td 设 , then PLC adjusts the actual regeneration time t 再生实 = t 再生 - t 再生变 , until Td 设 + Td 浮动低 ≤ Td 实 ≤ Td 设 + Td 浮动高 ; if Td 实 < Td 设 , then PLC adjusts the actual regeneration time t 再生实 = t 再生 + t 再生变 , until Td 设 + Td 浮动低 ≤ Td 实 ≤ Td 设 + Td 浮动高 ; (2) When the real-time dew point value Td 实 is adjusted to the range of Td 设 + Td 浮动低 ≤ Td 实 ≤ Td 设 + Td 浮动高 , the PLC records the time used for this cycle regeneration and records the regeneration flow rate Q 实时 through the flow meter and the equalization pressure P 塔 of the adsorption tower during equalization, calculates the regeneration flow rate Q 均压 in the adsorption tower during equalization, and then the cycle regeneration flow rate Q 再生 = Q 实时 + Q 均压 , according to the regeneration flow rate Q 再生 and under the condition of Td 设 + Td 浮动低 ≤ Td 实 ≤ Td 设 + Td 浮动高 , the regeneration time t 再生 performed in each subsequent cycle is obtained; When the real-time dew point value Td 实 is adjusted to Td 实 = Td 设 + Td 浮动低 , the PLC records the adsorption time at this time, and uses the actual adsorption time t 吸附实 as the adsorption time in the range of Td 设 + Td 浮动低 ≤ Td 实 ≤ Td 设 + Td 浮动高Under these conditions, the fixed adsorption time t for each subsequent cycle 吸附 .

[0007] As a preferred design, in the periodic time control mode, a fixed regeneration time t is used in each time period. 再生 and a fixed adsorption time t 吸附 And within each time period t 吸附 >t 再生 +t 浮动 .

[0008] As a preferred design, in the adaptive control mode, in step (1), if Td 实 >Td 设 The PLC adjusts the regeneration time in n cycles, with each cycle based on t. 再生变 Adjustments were made, and Td was compared after each adjustment. 实 and Td 设 Then, the actual regeneration time t when the nth cycle is reached... 再生实 =t 再生n -t 再生变 until Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 .

[0009] As a preferred design, in the adaptive control mode, in step (1), if Td 实 <Td 设 The PLC then adjusts the regeneration time over n cycles. Each cycle follows t 再生变 Adjustments were made, and Td was compared again after each adjustment. 实 and Td 设 Then, the actual regeneration time t when the nth cycle is reached... 再生实 =t 再生n +t 再生变 until Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 .

[0010] As a preferred design, in adaptive control mode, when the dew point setpoint Td 设 When the cycle changes, the initial regeneration time t is executed in each cycle. 再生 and initial fixed adsorption time t 吸附 All changes occur, and the process of steps (1) and (2) is repeated for control.

[0011] As a preferred design, in adaptive control mode, when the adsorption time t of each cycle is... 吸附 Once the relative time t is determined, 再生 Changes occur when the adsorption time t 吸附 ≤Regeneration time t 再生 +t 浮动 And Td 设 ≤Td 实 ≤Td 设 +Td 浮动低 If necessary, increase the orifice diameter of the regeneration valve in the regeneration device, each time according to a fixed orifice diameter D. 变 Increase the diameter, and confirm the dew point Td for the next cycle after each adjustment. 实 Is it in Td? 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 Within the range, and t 吸附 >t 再生 +t 浮动 ; D 实 =D 实n +D 变， Until the dew point Td 实 In Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 Within the range.

[0012] As a preferred design, when the regeneration flow rate Q in step (2) is... 再生 +Q 浮动 Reaching the set upper limit Q 设 Q 设 ≤Q 再生 +Q 浮动 If this happens, an alarm signal will be sent through the PLC.

[0013] A second objective of the present invention is to provide a control system for implementing the automatic control method for reducing gas loss in an adsorption dryer as described in any of the above claims, comprising a control cabinet, a gas source, and an adsorption dryer, wherein the control cabinet and the gas source are both connected to the adsorption dryer, the adsorption dryer comprising an adsorption tower A, an adsorption tower B, and a regeneration device, the outlet of the gas source being connected to the inlet ends of the adsorption tower A and the adsorption tower B, the outlet ends of the adsorption tower A and the adsorption tower B being connected to dew point sensors, and the adsorption tower A and the adsorption tower B being connected to each other.

[0014] As a preferred design, the regeneration device includes a regeneration valve and a flow meter, both of which are installed on the connecting pipeline between adsorption tower A and adsorption tower B; The regeneration device also includes a temperature sensor and a pressure sensor, both of which are installed on the connecting pipeline between adsorption tower A and adsorption tower B, with two of each sensor installed.

[0015] As a preferred design, the gas in the adsorption tower A enters the adsorption tower B through temperature sensor A, pressure sensor A, check valve A, regeneration valve, flow meter, check valve B, pressure sensor B, and temperature sensor B; The gas in the adsorption tower B enters the adsorption tower A through temperature sensor B, pressure sensor B, check valve C, regeneration valve, flow meter, check valve D, pressure sensor A, and temperature sensor A. The adsorption towers A and B are also equipped with silencers.

[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The automatic control method of the present invention adjusts the regeneration time and regeneration flow rate according to the set dew point value, while ensuring that the dew point is within the set floating range, so as to minimize the gas loss and optimize the adsorption time, make full use of the adsorbent, thereby reducing the power consumption and maintenance cost of the whole machine.

[0017] 2. The automatic control method of the present invention allows for controllable regeneration valve diameter, fully utilizes the adsorbent, and extends its maintenance time. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 The structure diagram of the automatic control system provided by the present invention.

[0019] The markings in the diagram are: 1: Control cabinet; 2: PLC; 3: Air source; 4: Solenoid valve A; 5: Solenoid valve C; 6: Solenoid valve B; 7: Solenoid valve D; 8: Silencer A; 9: Silencer B; 10: Adsorption tower A; 11: Adsorption tower B; 12: Regeneration device; 13: Temperature sensor A; 14: Pressure sensor A; 15: Check valve A; 16: Check valve C; 17: Pressure sensor B; 18: Temperature sensor B; 19: Regeneration valve; 20: Flow meter; 21: Check valve D; 22: Check valve B; 23: Check valve E; 24: Check valve F; 25: Dew point sensor; 26: Ball valve; 27: User terminal; 28: Adsorption dryer. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0021] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other embodiments, well-known structures, circuits, materials, or methods have not been specifically described in order to avoid obscuring the invention.

[0022] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0023] In the description of this invention, the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0024] To address the current limitations in effectively controlling and minimizing gas loss in adsorption dryers, this invention provides an automatic control method for reducing gas loss in adsorption dryers, comprising the following steps: 1. In the initial stage of operation of the adsorption dryer, the dew point value (described by its absolute value for ease of description) gradually increases. Therefore, a periodic time control mode is adopted. This process has ample regeneration time (i.e., high air loss) and a relatively short adsorption time, allowing the compressed air produced by the adsorption dryer to quickly reach the set dew point value. This process uses an initial fixed regeneration time t. 再生 and the initial fixed adsorption time t 吸附 , and t 吸附 >t 再生 +t 浮动 .

[0025] 2. After the set multiple periodic (e.g., 5 or 10 cycles) operating modes have been completed, the system enters the adaptive control mode.

[0026] (1) The PLC records the real-time dew point value Td from the dew point sensor. 实 , and the dew point setting value Td 设 Compare them.

[0027] If Td 实 >Td 设 Then the PLC adjusts the actual regeneration time t 再生实 =Initial fixed regeneration time t 再生 - Fixed adjustment time t 再生变 Then, in the next cycle, the PLC again calculates the real-time dew point value Td. 实 With dew point setting value Td 设 Compare, each time press t 再生变 Adjustments and comparisons were made, t 再生实 =Real-time regeneration time t of the nth cycle 再生n -t 再生变 After adjustments in the 1st, 2nd, 3rd...nth cycles, until Td... 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 .

[0028] Where n is an integer greater than 1. To meet user requirements for the dew point value, a range higher than the user's needs is set to ensure the dew point is controlled within this range; if it exceeds this range, adjustments are necessary. For example, Td... 设 =15、Td 浮动低 =1、Td 浮动高 =5, then Td 实The value should be controlled within the range of 16-20. Therefore, Td 浮动低 This represents the dew point setting Td relative to user needs. 设 Set a low floating value, Td 浮动高 This represents the dew point setting Td relative to user needs. 设 The setting is a floating high value.

[0029] If Td 实 <Td 设 Then the PLC adjusts the regeneration time t 再生实 =t 再生 +t 再生变 Then, in the next cycle, the PLC again calculates the real-time dew point value Td. 实 Dew point and set value Td 设 Compare, and press t each time. 再生变 Adjustments and comparisons were made, t 再生实 =t 再生n +t 再生变 until Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 .

[0030] (2) When Td 实 In Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 When the value is within the specified range, the PLC records this cycle (i.e., the real-time dew point value Td). 实 Adjust to Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 The regeneration flow rate Q through the flow meter within the specified time period (when within the specified range) 实时 Record the equalization pressure P of the pressure sensor on the adsorption tower when the equalization pressure is reached. 塔 The regeneration flow rate Q in the adsorption tower under equal pressure is calculated using a PLC. 均压 =P 塔 *V 塔 *10 (V) 塔 (where the adsorption tower volume is used), calculate the regeneration flow rate Q for this cycle. 再生 =Q 实时 +Q 均压 Calculate Q at this time 再生 The data is recorded and stored in the PLC to determine the initial regeneration time t to be executed in subsequent cycles. 再生 Then when Td 实In Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 When the range is within a certain range, the regeneration time used by the regeneration device in each regeneration cycle is t. 再生 Therefore, by controlling the regeneration flow rate Q 再生 This allows control over the regeneration time t in each cycle. 再生 The regeneration time reaches the regeneration time t. 再生 This means closing the corresponding valve to complete the regeneration within the corresponding cycle.

[0031] Among them, Q 再生 Q represents the regeneration flow rate, i.e., the gas loss. 实时 Q represents the flow rate passing through the flow meter from the point when pressure equalization stops until pressure equalization is resumed. 均压 This represents the flow rate in the adsorption tower during pressure equalization.

[0032] When the real-time dew point value Td is... 实 Adjust to Td 实 =Td 设 +Td 浮动低 At this time, the PLC records the adsorption time (i.e., the real-time dew point value Td). 实 =Td 设 +Td 浮动低 The adsorption time taken during this cycle, and the actual adsorption time t. 吸附实 As its adaptive adsorption time, as in Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 Under these conditions, the initial fixed adsorption time t for each subsequent cycle 吸附 Soon 吸附 Replace with t 吸附实 .

[0033] Using the above control methods, the time of the adsorption and regeneration processes can be automatically adjusted in the adaptive control mode to keep the dew point value within the set tolerance range, thereby keeping the gas loss of the adsorption dryer at a minimum.

[0034] When the user's required dew point setting value Td 设 When changes occur, the adsorption time t in both periodic time control mode and adaptive control mode. 吸附 Regeneration time t 再生 All of these will change, and the control system will repeat the above steps again.

[0035] As the adsorption dryer operates for longer periods, its regeneration and adsorption performance will change. In adaptive control mode, when the adsorption time t... 吸附 Once relatively determined, if the regeneration time changes with operation, such as when the adsorption time t... 吸附 ≤t 再生 +t 浮动 And Td 设 ≤Td 实 ≤d 设 +Td 浮动低 If necessary, the diameter of the regeneration valve in the regeneration device needs to be increased, and the diameter D should be adjusted each time. 变 To increase, D 实 =D 设 +D 变 Among them, D 实 D represents the actual diameter of the regeneration valve. 设 D is the initial fixed diameter of the regeneration valve. 变 The nozzle diameter is adjusted to a fixed value. After increasing the nozzle diameter, the dew point Td for the next cycle is confirmed. 实 Is it in Td? 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 Within the range, and t 吸附 >t 再生 +t 浮动 Press D each time. 变 Adjustments and comparisons were made, D 实 =D 实n +D 变， Until the dew point Td 实 In Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 Within the range, and t 吸附 >t 再生 +t 浮动 D 实n This represents the actual flow diameter of the regeneration valve for the 1st, 2nd, 3rd...nth cycle. 浮动 To set a fixed safety time to ensure t 吸附 >t 再生 .

[0036] And when the regeneration flow rate Q involved in the above steps 再生 When it is too large, the set upper limit Q is reached. 设 Q 设 ≤Q 再生 +Q 浮动If this happens, an alarm signal will be sent via the PLC, prompting the user to replace the adsorbent or check for other problems. Among these, Q... 设 To set the upper limit of regeneration flow rate, Q 浮动 For a fixed flow rate adjustment value (e.g., 2m³, each adjustment is made in increments of 2m³).

[0037] The control method provided by this invention does not depend on specific operators; it only requires setting the required dew point Td. 设 After setting the parameters, the equipment confirms the initial dew point through the periodic time control mode, then switches to adaptive mode. It gradually adjusts the regeneration time, adsorption time, and opening time of the exhaust solenoid valve and regeneration valve, and controls the flow rate through the regeneration valve. In adaptive mode, it automatically adjusts the adsorption and regeneration time to keep the dew point value within the set tolerance range, thereby keeping the gas loss of the adsorption dryer at a minimum.

[0038] This invention further balances adsorption, regeneration time and regeneration diameter by adjusting the diameter of the regeneration device and the adsorption regeneration time, combined with pressure and dew point sensors, under different demand pressure and dew point requirements, and controls the gas loss in real time, so as to minimize the gas loss of the adsorption dryer, thereby reducing the power consumption and maintenance cost of the whole machine.

[0039] The automatic control method for reducing gas loss in an adsorption dryer according to the present invention will be described in more detail below with reference to a specific control system.

[0040] Example 1: The control system used in this embodiment is as follows: Figure 1 Of course, the automatic control method of the present invention is not limited to, for example... Figure 1 The control system implementation in the example is shown below.

[0041] like Figure 1As shown, the system includes a control cabinet 1, an air source 2, an adsorption dryer 28, a dew point sensor 25, a ball valve 26, and a user terminal 27. The control cabinet includes a PLC 2 and its supporting components. Both the control cabinet 1 and the air source 3 are connected to the adsorption dryer 28. The adsorption dryer 28 includes an adsorption tower A 10, an adsorption tower B 11, a regeneration device 12, multiple solenoid valves (4~7), two silencers, and multiple one-way valves (23~24). The outlet of the air source 3 is connected to the inlet of adsorption tower A 10 and adsorption tower B 11. The outlets of adsorption tower A 10 and adsorption tower B 11 are both connected to the dew point sensor 25. Adsorption tower A 10 and adsorption tower B 11 are also connected to each other. The regeneration device 12 includes two temperature sensors, two pressure sensors, a regeneration valve 19, multiple check valves (15~16, 21~22), and a flow meter 20. The regeneration valve 19 and the flow meter 20 are both installed on the connecting pipeline between adsorption tower A 10 and adsorption tower B 11. The temperature sensors and pressure sensors are both installed on the connecting pipeline between adsorption tower A 10 and adsorption tower B 11.

[0042] Specifically, such as Figure 1 As shown, the inlet end of adsorption tower A 10 is equipped with solenoid valves A 4 and B 6, and silencer A 8 is located at the rear end of solenoid valve B 6. The inlet end of adsorption tower B 11 is equipped with solenoid valves C 5 and D 7, and silencer B 9 is located at the rear end of solenoid valve D 7. The regeneration device 12 includes temperature sensors A 13 and B 18, pressure sensors A 14 and B 17, and check valves A 15, B 22, C 16, and D 21. Check valves E 23 and F 24 are respectively installed on the outlet pipelines of adsorption towers A 10 and B 11.

[0043] Gas from adsorption tower A10 passes through temperature sensor A13, pressure sensor A14, check valve A15, regeneration valve 19, flow meter 20, check valve B22, pressure sensor B17, and temperature sensor B18 before entering adsorption tower B11. Gas from adsorption tower B11 passes through temperature sensor B18, pressure sensor B17, check valve C16, regeneration valve 19, flow meter 20, check valve D21, pressure sensor A14, and temperature sensor A13 before entering adsorption tower A10.

[0044] PLC 2 is used to control the adsorption dryer, enabling periodic switching between adsorption tower A 10 and adsorption tower B 11, and recording, storing, and calculating dew point, pressure, and flow rate.

[0045] The regeneration device 12 controls the regeneration flow rate. It controls the regeneration orifice diameter via regeneration valve 19, measures the flow rate via flow meter 20, and monitors the pressure in the adsorption tower via pressure sensors A 14 and B 17. The regeneration device 12 is connected to control cabinet 1. Control cabinet 1 calculates the pressure difference change based on the signals collected by the pressure sensors and adjusts the valve diameter in real time using a preset algorithm to maintain a constant regeneration gas flow rate. This method optimizes energy consumption during the regeneration process while ensuring the stability of the adsorbent regeneration effect. The device has a simple structure, precise control, and is suitable for adsorption dryer systems under various operating conditions.

[0046] The basic operating flow of the adsorption dryer in this embodiment is as follows: First, compressed air is supplied by air source 3 and enters adsorption tower A10 through solenoid valve A4. The adsorbent in adsorption tower A10 adsorbs the compressed air, and the dry air is divided into two parts. One part is supplied to user end 27 through one-way valve E23, dew point sensor 25, and ball valve 26; the other part enters adsorption tower B11 through regeneration valve 19 and flow meter 20 of regeneration device 12. The water-laden air is discharged through solenoid valve D7 and silencer B9, and the moisture in adsorption tower B11 is carried out. During switching, compressed air is supplied by air source 3 and enters adsorption tower B 11 through solenoid valve C 5. The adsorbent in adsorption tower B 11 adsorbs the compressed air, and the dry air is divided into two parts. One part is delivered to user end 27 through one-way valve F 24, dew point sensor 25, and ball valve 26; the other part enters adsorption tower A 10 through regeneration valve 19 and flow meter 20 of regeneration device 12. The water-laden air is discharged through solenoid valve B 6 and silencer A 8, and the moisture in adsorption tower A 10 is carried out. The two towers switch with each other to form a cycle.

[0047] The method for controlling gas loss using the control system in this embodiment is as follows: Set Td 设 =20℃ (normally -20℃, for ease of description, the dew point value is described using its absolute value), Td 浮动低 =2℃, Td 浮动高 =4℃、t 再生变 =0.5min, V 塔 =0.02m³, t 浮动 =4min、D 设 =2mm, D 变 =0.2mm, Q 设 =8m³、Q 浮动 =1m³; Periodic operation setting t 再生 =5min,t 吸附 =10min, equalization time t 均压 =0.5min; Set to run for 5 cycles; After the equipment is started, compressed air enters from the bottom of adsorption tower A10 through solenoid valve A4. At this time, solenoid valves B6 and C5 are closed, while solenoid valves A4 and D7 are open. Adsorption tower A10 begins adsorption, and adsorption tower B11 begins regeneration. After 5 minutes, solenoid valve D7 closes, stopping regeneration. After 10 minutes, solenoid valve C5 opens, initiating pressure equalization. After 30 seconds, solenoid valve A4 closes, and solenoid valve B6 opens. At this time, adsorption tower B11 begins adsorption, and adsorption tower A10 begins regeneration. After 5 minutes, solenoid valve B6 closes, stopping regeneration. After 10 minutes, solenoid valve A4 opens, initiating pressure equalization. After 30 seconds, solenoid valve C5 closes, and solenoid valve D7 opens. At this time, adsorption tower A10 begins adsorption, and adsorption tower B11 begins regeneration. This cycle repeats, forming a periodic operation.

[0048] After running for 5 cycles, Td 实 At 30℃, the equipment enters adaptive control mode, at which point Td 实＞ Td 设 PLC adjustment time regeneration time t 再生实 =5-0.5=4.5min, after one cycle, Td 实 =28℃, PLC adjustment time regeneration time t 再生实 =4.5-0.5=4min, after one cycle, Td 实 =26℃, PLC adjustment time regeneration time t 再生实 =4-0.5=3.5min, after one cycle, Td 实 =25℃, PLC adjustment time regeneration time t 再生实 =3.5-0.5=3min, after one cycle, Td 实 =23, at this time Td 实 Within the set range, i.e., 22 ≤ 23 ≤ 24, the regeneration flow rate Q passing through the flow meter during this cycle. 实时 =5m³, the equalizing pressure P of adsorption tower A 10 and / or adsorption tower B 11 塔 =0.6MPa, by calculating Q 均压 =0.6*0.02*10=0.12m³, total regeneration flow rate Q 再生 =5 + 0.12 = 5.12 m³. At this point, the actual regeneration value for each subsequent cycle is determined to be Q. 再生 =5.12m³, regeneration flow rate Q 再生 =5.12m³. This means the subsequent equipment operates automatically, with each cycle following Q. 再生 =5.12m³, t 再生 Regeneration takes 3 minutes.

[0049] Entering adaptive control mode, when Td 实 At 22℃, the PLC records the adsorption time, t. 吸附实 =12min, the equipment automatically adjusts the adsorption time, reducing the original periodic adsorption time t 吸附 =10min adjusted to t 吸附实 =12min, meaning the subsequent equipment runs automatically, with each cycle consisting of 12 minutes of adsorption.

[0050] As the adsorption dryer operates for longer periods, its regeneration and adsorption performance will change. In adaptive control mode, when the adsorption time t... 吸附 Once the relative value is determined, i.e., t 吸附 =12min. If the regeneration time changes with operation, such as when the adsorption time t 吸附 ≤t 再生 +t 浮动 And Td 实 ≤Td 设 +Td 浮动低 When, such as t 再生 =9min,Td 实 At 21℃, if 12min ≤ 9min + 4min, then the diameter of the regeneration valve in the regeneration device needs to be increased, and the diameter D should be adjusted each time. 变 =0.2mm increase, D 实1 =D 设 +D 变 =2 + 0.2 = 2.2 mm. t 再生实 =9-0.5=8.5min、Td 实 =21.5℃; D 实2 =D 实1 +D 变 =2.2 + 0.2 = 2.4 mm. t 再生实 =8.5-0.5=8min、Td 实 =22℃; D 实3 =D 实2 +D 变 =2.4 + 0.2 = 2.6 mm. t 再生实 =8-0.5=7.5min、Td 实 =22.5℃; at this time t 吸附 =12>7.5+4 and dew point Td 实 Within the range of 20+2≤22.5≤20+4.

[0051] The regeneration time increases, corresponding to the regeneration flow rate Q. 再生 As it increases, it reaches the set upper limit Q. 设 =8m³, Q 设 ≤Q再生 +Q 浮动 When, such as Q 再生 =7m³, 8m³≤7+1m³, at which point the PLC will issue an alarm signal, prompting the user to replace the adsorbent or check for other problems.

[0052] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An automatic control method for reducing gas loss in an adsorption dryer, characterized in that, include: In the initial stage of operation of the adsorption dryer, a periodic time control mode is adopted. After the periodic time control mode has completed its operation, the adaptive control mode will be used. In the adaptive control mode: (1) Comparison of the measured real-time dew point value Td 实 With dew point setting value Td 设 , if Td 实 >Td 设 Then the PLC adjusts the actual regeneration time t 再生实 =t 再生 -t 再生变 until Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 ; If Td 实 <Td 设 Then the PLC adjusts the actual regeneration time t 再生实 =t 再生 +t 再生变 until Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 ; (2) When the real-time dew point value Td is... 实 Adjust to Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 When the range is specified, the PLC records the time taken for regeneration in this cycle and the regeneration flow rate Q passing through the flow meter during that time cycle. 实时 The equalizing pressure P of the adsorption tower during the equalization process. 塔 Calculate the regeneration flow rate Q in the adsorption tower under equal pressure. 均压 Then the regeneration flow rate Q in this cycle 再生 =Q 实时 +Q 均压 According to the regeneration flow rate Q 再生 And in Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 Under the condition of obtaining the regeneration time t of each subsequent cycle 再生 ; When the real-time dew point value Td is... 实 Adjust to Td 实 =Td 设 +Td 浮动低 At this time, the PLC records the adsorption time, and uses this as the actual adsorption time t. 吸附实 As in Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 Under these conditions, the fixed adsorption time t for each subsequent cycle 吸附 .

2. The automatic control method for reducing gas loss in an adsorption dryer according to claim 1, characterized in that, In the periodic time control mode, a fixed regeneration time t is used in each time period. 再生 and a fixed adsorption time t 吸附 And within each time period t 吸附 >t 再生 +t 浮动 .

3. The automatic control method for reducing gas loss in an adsorption dryer according to claim 1, characterized in that, In the adaptive control mode, in step (1), if Td 实 >Td 设 The PLC adjusts the regeneration time in n cycles, with each cycle based on t. 再生变 Adjustments were made, and Td was compared after each adjustment. 实 and Td 设 Then, the actual regeneration time t when the nth cycle is reached... 再生实 =t 再生n -t 再生变 until Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 .

4. The automatic control method for reducing gas loss in an adsorption dryer according to claim 1, characterized in that, In the adaptive control mode, in step (1), if Td 实 <Td 设 The PLC then adjusts the regeneration time over n cycles. Each cycle follows t 再生变 Adjustments were made, and Td was compared again after each adjustment. 实 and Td 设 Then, the actual regeneration time t when the nth cycle is reached... 再生实 =t 再生n +t 再生变 until Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 .

5. The automatic control method for reducing gas loss in an adsorption dryer according to claim 1, characterized in that, In adaptive control mode, when the dew point setpoint Td 设 When the cycle changes, the regeneration time t is performed in each cycle. 再生 and adsorption time t 吸附 All changes occur, and the process of steps (1) and (2) is repeated for control.

6. The automatic control method for reducing gas loss in an adsorption dryer according to claim 1, characterized in that, In adaptive control mode, when the adsorption time t is performed in each cycle 吸附 Once the relative time t is determined, 再生 Changes occur when the adsorption time t 吸附 ≤Regeneration time t 再生 +t 浮动 And Td 设 ≤Td 实 ≤d 设 +Td 浮动低 If necessary, increase the orifice diameter of the regeneration valve in the regeneration device, each time according to a fixed orifice diameter D. 变 Increase the diameter, and confirm the dew point Td for the next cycle after each adjustment. 实 Is it in Td? 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 Within the range, and t 吸附 >t 再生 +t 浮动 ; D 实 =D 实n +D 变， Until the dew point Td 实 In Td 设 +Td 浮动低 ≤Td 实 ≤Td 设 +Td 浮动高 Within the range.

7. The automatic control method for reducing gas loss in an adsorption dryer according to claim 1, characterized in that, When the regeneration flow rate Q mentioned in step (2) 再生 +Q 浮动 Reaching the set upper limit Q 设 Q 设 ≤Q 再生 +Q 浮动 If this happens, an alarm signal will be sent through the PLC.

8. A control system for implementing an automatic control method for reducing gas loss in an adsorption dryer as described in any one of claims 1 to 7, characterized in that, The device includes a control cabinet, a gas source, and an adsorption dryer. The control cabinet and the gas source are both connected to the adsorption dryer. The adsorption dryer includes an adsorption tower A, an adsorption tower B, and a regeneration device. The outlet of the gas source is connected to the inlet of adsorption tower A and adsorption tower B. The outlets of adsorption tower A and adsorption tower B are both connected to dew point sensors. Adsorption tower A and adsorption tower B are also connected to each other.

9. The control system according to claim 8, characterized in that, The regeneration device includes a regeneration valve and a flow meter, both of which are installed on the connecting pipeline between adsorption tower A and adsorption tower B. The regeneration device also includes a temperature sensor and a pressure sensor, both of which are installed on the connecting pipeline between adsorption tower A and adsorption tower B, with two of each sensor installed.

10. The control system according to claim 9, characterized in that, The gas in the adsorption tower A enters the adsorption tower B through temperature sensor A, pressure sensor A, check valve A, regeneration valve, flow meter, check valve B, pressure sensor B, and temperature sensor B. The gas in the adsorption tower B enters the adsorption tower A through temperature sensor B, pressure sensor B, check valve C, regeneration valve, flow meter, check valve D, pressure sensor A, and temperature sensor A. The adsorption towers A and B are also equipped with silencers.

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