A control method of an automatic drainage exhaust gas water washing treatment device

Abstract

The application discloses a kind of automatic drainage's tail gas water washing treatment device and its fault self-identification method, it is related to tail gas processing technical field.The water washing tank, water storage tank and controller are included;water washing tank and water storage tank are provided with the connecting pipe of both sides at first liquid level height;The controller is electrically connected with the air inlet valve, first liquid level meter, first drain valve, air outlet valve, air charging valve, second liquid level meter, second drain valve, first pressure sensor, second pressure sensor arranged on water washing tank and water storage tank, and the opening and closing of valve are controlled according to the detected pressure signal and liquid level signal.The application can cache the redundant condensate water generated in the process of tail gas water washing, make the uncertain drainage time caused by the water content in tail gas relatively stable, and realize automatic control, without daily inspection personnel.

Description

Technical Field

[0001] This invention relates to the field of exhaust gas treatment technology, and in particular to an automatic drainage exhaust gas washing treatment device and its fault self-identification method. Background Technology

[0002] To ensure measurement accuracy, online flue gas monitoring equipment often employs methods such as isokinetic sampling or constant-flow sampling. Both methods require automatic adjustment via sensors, flow controllers, and other equipment. However, because flue gas contains large amounts of water vapor and inorganic salts, and its temperature is typically above 120°C, these substances can not only reduce the accuracy of sensors and flow controllers but may even damage the equipment.

[0003] The exhaust gas washing treatment device can quickly reduce the temperature of flue gas and effectively remove water vapor and inorganic salts. However, after the water vapor in the flue gas cools down, a large amount of condensate is stored in the device. Drainage requires procedures such as shutting down the sampling pump, disconnecting the sampling circuit, and introducing compressed air. Because this process involves many valves and the operating sequence is strictly required, otherwise, condensate may be drawn back into the equipment, damaging it. Furthermore, the moisture content in the flue gas varies greatly depending on the raw materials, making drainage time uncertain. Inspection personnel must ensure daily on-site checks; forgetting or failing to inspect for other reasons may result in condensate overflowing and entering other equipment, causing damage. In addition, because the valves operate in a weakly acidic environment for extended periods, especially the sealing components, damage is easily caused and may not be detected in time.

[0004] Therefore, designing an exhaust gas washing treatment device that can automatically drain water is one of the urgent problems to be solved. Summary of the Invention

[0005] In order to solve at least one of the technical problems mentioned in the background art, the present invention aims to provide an automatic drainage exhaust gas washing treatment device and its fault self-identification method, which can automatically drain the exhaust gas during the washing process.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] An automatic drainage exhaust gas washing treatment device includes a washing tank, a water storage tank, and a controller;

[0008] The washing tank is equipped with an air inlet pipe at the top and an air inlet valve on the air inlet pipe; the washing tank is equipped with a first level gauge and a first drain pipe at the bottom and a first drain valve on the first drain pipe.

[0009] The top of the water storage tank is equipped with an air outlet pipe and an air filling pipe. An air outlet valve is installed on the air outlet pipe, and an air pump is connected to the end of the air outlet pipe. An air filling valve is installed on the air filling pipe. A second liquid level gauge is installed on the water storage tank, and a second drain pipe is installed at the bottom. A second drain valve is installed on the second drain pipe.

[0010] The air inlet pipe is equipped with a first pressure sensor for detecting the pressure inside the air inlet pipe when it is outside the air inlet valve, and the air outlet pipe is equipped with a second pressure sensor for detecting the pressure inside the water storage tank; the washing tank and the water storage tank are connected by a connecting pipe at the first liquid level.

[0011] The controller is electrically connected to the air inlet valve, the first liquid level gauge, the first drain valve, the air outlet valve, the air filling valve, the second liquid level gauge, the second drain valve, the first pressure sensor, and the second pressure sensor, and controls the opening and closing of the valves based on the detected pressure signal and liquid level signal.

[0012] Furthermore, the control method of the controller is as follows:

[0013] When the first level gauge detects that the liquid level in the washing tank has reached the first level height, the excess water flows into the storage tank along the connecting pipe. When the second level gauge detects that the liquid level in the storage tank has reached the first level height, the system enters the drainage state. In the drainage state, the controller closes the air inlet valve and the air outlet valve, and opens the air filling valve to fill the washing tank and the storage tank with compressed air. When the second pressure sensor detects that the pressure in the storage tank has risen to the first pressure threshold, the controller opens the first drain valve and the second drain valve to drain the water.

[0014] Furthermore, the controller also controls the closing of the first drain valve and the second drain valve, as follows:

[0015] When the first level gauge detects that the liquid level in the washing tank is lower than the second level height, the controller closes the first drain valve;

[0016] When the second level gauge detects that the water level in the storage tank is lower than the second level height, the air valve is closed. When the second pressure sensor detects that the pressure in the storage tank drops to the second pressure threshold, the controller closes the second drain valve and opens the air outlet valve. When the second pressure sensor detects that the pressure in the storage tank drops to the third pressure threshold, the controller opens the air inlet valve.

[0017] The second liquid level is lower than the first liquid level; the first pressure threshold is higher than the second pressure threshold, and the third pressure threshold is lower than the second pressure threshold.

[0018] Furthermore, the first pressure threshold is 100 kPa, the second pressure threshold is 0, and the third pressure threshold is -10 kPa.

[0019] Furthermore, the first level gauge includes a plurality of level sensors arranged sequentially along the vertical direction around the periphery of the washing tank.

[0020] Furthermore, the second level gauge includes a plurality of level sensors arranged sequentially along the vertical direction around the periphery of the water storage tank.

[0021] A fault self-identification method for an automatic drainage exhaust gas washing treatment device identifies whether each valve is faulty based on the pressure signal changes in the tank under the control status of each valve during startup, operation, and drainage.

[0022] Furthermore, during the startup process, the air inlet valve, the first drain valve, the second drain valve, and the air outlet valve are closed, and the air filling valve is opened; the air filling valve is closed when the pressure measured by the second pressure sensor reaches 100 kPa; if the pressure value measured by the second pressure sensor remains unchanged during the compressed air filling process, it indicates that the air filling valve is faulty.

[0023] The second pressure sensor continuously detects for 30 seconds. If the measured pressure value remains unchanged, it indicates that the intake valve, first drain valve, second drain valve, exhaust valve, and inflation valve are normal. If the measured pressure value decreases, the pressure in the intake pipe is detected by the first pressure sensor. If the measured pressure value is positive, it indicates that the intake valve is faulty. Otherwise, wait for the air pump to turn on and continuously detect the pressure value of the second pressure sensor. If the pressure value decreases rapidly and eventually becomes less than 0, it indicates that the exhaust valve is faulty. If the pressure value decreases at a constant rate or the pressure value is always greater than or equal to 0, it indicates that the first drain valve or the second drain valve is faulty.

[0024] Furthermore, during the operation, after receiving the air pump operation signal for 1 minute, the system enters the operation detection state. If the pressure value detected by the second pressure sensor is less than -60 kPa and the pressure value detected by the first pressure sensor is greater than -5 kPa, it indicates a fault in the intake valve. If the pressure value detected by the second pressure sensor is between -30 kPa and -5 kPa, the pressure value detected by the first pressure sensor is between -20 kPa and -5 kPa, and the pressure value detected by the second pressure sensor is less than the pressure value detected by the first pressure sensor, it indicates a fault in either the first or second drain valve. If the pressure values ​​detected by both the first and second pressure sensors are between -5 kPa and 0 Pa, it indicates a fault in the exhaust valve. If the pressure values ​​detected by both the first and second pressure sensors are greater than 0, it indicates a fault in the inflation valve.

[0025] Furthermore, during the drainage process, when the liquid level in the storage tank reaches the first liquid level height, the drainage state is entered; the air inlet valve and air outlet valve are closed, and the air filling valve is opened; when the pressure value detected by the second pressure sensor reaches 100 kPa, the air filling valve is closed; if the pressure value detected by the second pressure sensor remains unchanged, it indicates that the air filling valve is faulty.

[0026] The second pressure sensor continuously monitors for 30 seconds. If the pressure value remains constant, it indicates that the inlet valve, first drain valve, second drain valve, outlet valve, and inflation valve are functioning normally. Open the inflation valve and then open the first and second drain valves to begin drainage. If the pressure value detected by the second pressure sensor decreases while the pressure value detected by the first pressure sensor increases, it indicates a fault in the inlet valve. If the pressure value detected by the second pressure sensor is negative, it indicates a fault in the outlet valve. If the pressure value detected by the second pressure sensor decreases and remains positive, it indicates a fault in either the first or second drain valve, preventing it from closing completely. During drainage, if the liquid level detected by the first level gauge does not show a downward trend within 5 seconds, it indicates a fault in the first drain valve, preventing it from opening. Similarly, if the liquid level detected by the second level gauge does not show a downward trend within 5 seconds, it indicates a fault in the second drain valve, preventing it from opening.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] This invention incorporates a water storage tank connected to a washing tank to buffer excess condensate generated during the exhaust gas washing process. This stabilizes the previously uncertain drainage time caused by the moisture content in the exhaust gas, while also extending the drainage cycle and reducing the number of valve operations, effectively prolonging the equipment's lifespan. Furthermore, this invention uses a controller to manage valve opening and closing based on detected pressure and liquid level signals, preventing condensate overflow without requiring daily on-site inspections. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention.

[0030] Figure 2 This is a control principle diagram of an embodiment of the present invention.

[0031] In the diagram: 1. Washing tank; 11. Air inlet pipe; 12. Air inlet valve; 13. First pressure sensor; 14. First level gauge; 15. First drain pipe; 16. First drain valve; 2. Water storage tank; 21. Air outlet pipe; 22. Air outlet valve; 23. Second pressure sensor; 24. Second level gauge; 25. Second drain pipe; 26. Second drain valve; 27. Air filling pipe; 28. Air filling valve; 3. Connecting pipe; 4. Air pump; 5. Flow meter. Detailed Implementation

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Example 1:

[0034] Please see Figure 1 This embodiment provides an automatic drainage exhaust gas washing treatment device, including a washing tank 1, a water storage tank 2 and a controller;

[0035] The top of the washing tank 1 is provided with an air inlet pipe 11, and an air inlet valve 12 is provided on the air inlet pipe 11. The exhaust gas to be treated enters the washing tank 1 through the air inlet pipe 11 for water washing treatment. The condensate generated during the water washing process accumulates in the washing tank 1.

[0036] In order to detect the liquid level of condensate accumulated in the washing tank, a first liquid level gauge 14 is provided on the washing tank 1; in order to facilitate the drainage of condensate accumulated in the washing tank 1, a first drain pipe 15 is provided at the bottom of the washing tank 1, and a first drain valve 16 is provided on the first drain pipe 15.

[0037] The water storage tank 2 is located near the washing tank 1 to buffer excess condensate. A vent pipe 21 with a vent valve 22 is installed at the top of the water storage tank 2. Similarly, a second level gauge 24 is installed on the water storage tank 2 to detect the condensate level. A second drain pipe 25 with a second drain valve 26 is installed at the bottom to facilitate the drainage of accumulated condensate from the water storage tank 2.

[0038] The air inlet pipe 11 is equipped with a first pressure sensor 13 for detecting the pressure inside the air inlet pipe 11 when it is outside the air inlet valve 12; the air outlet pipe 21 is equipped with a second pressure sensor 23 for detecting the pressure inside the water storage tank 2. The washing tank 1 and the water storage tank 2 are connected by a connecting pipe 3 at a first liquid level, so that excess condensate in the washing tank 1 can enter the water storage tank 2 through the connecting pipe 3, and gas can also flow between the washing tank 1 and the water storage tank 2.

[0039] To enable the operation of the entire device, an air pump 4 is also connected to the end of the exhaust pipe 21. When the air pump 4 is running, the exhaust gas is discharged after passing through the inlet pipe 11, the water washing tank 1, the connecting pipe 3, the water storage tank 2, and the exhaust pipe 21 in sequence.

[0040] In this embodiment, in order to facilitate the discharge of condensate from the washing tank 1 and the storage tank 2, the storage tank 2 is also provided with an air inlet pipe 27 and an air inlet valve 28. Compressed air is injected into the storage tank 2 through the air inlet pipe 27, thereby increasing the pressure in the washing tank 1 and the storage tank 2 and accelerating the discharge of condensate from the first drain pipe 15 and / or the second drain pipe 25.

[0041] The controller is electrically connected to the air inlet valve 12, the first liquid level gauge 14, the first drain valve 16, the air outlet valve 22, the air filling valve 28, the second liquid level gauge 24, the second drain valve 26, the first pressure sensor 13, and the second pressure sensor 23, and controls the opening and closing of the valves according to the detected pressure signal and liquid level signal.

[0042] The first level gauge 14 includes a plurality of level sensors arranged in sequence along the vertical direction around the circumference of the washing tank, including level sensor 141, level sensor 142, level sensor 143, level sensor 144, and level sensor 145 from top to bottom. The number of level sensors is unlimited.

[0043] Similarly, the second level gauge 24 includes a plurality of level sensors arranged in sequence along the vertical direction on the two sides of the water storage tank, including level sensor 241, level sensor 242, level sensor 243, level sensor 244, and level sensor 245 from top to bottom.

[0044] Reference Figure 2 The controller is connected to a liquid level detection unit, a pressure detection unit, a key input unit, a communication unit, a valve control unit, an information display unit, and a power input unit.

[0045] The liquid level detection unit is used to detect the liquid level in the washing tank 1 and the storage tank 2, that is, to receive the liquid level information detected by the first liquid level gauge 14 and the second liquid level gauge 24.

[0046] The pressure detection unit is used to detect the pressure in the washing tank 1 and the water storage tank 2, that is, to receive the pressure information detected by the first pressure sensor 13 and the second pressure sensor 23.

[0047] The key input unit is used to input external information and set the control parameters of the controller.

[0048] The communication unit is used to communicate with external devices and send liquid level information, equipment operating status, fault information, etc.

[0049] The valve control unit is used to control various valves on the washing tank 1 and the storage tank 2, including the air inlet valve 12, the first drain valve 16, the air outlet valve 22, the air filling valve 28, and the second drain valve 26.

[0050] The information display unit includes a liquid crystal display screen for displaying liquid level information, equipment operating status, fault information, etc.

[0051] The power input unit is used to supply power to the overall device.

[0052] Specifically, the control method of the controller is as follows:

[0053] After the exhaust gas enters the water washing tank 1, the water vapor in the exhaust gas condenses upon cooling, causing the liquid level in the water washing tank 1 to rise continuously. Liquid level sensors 145, 144, 143, 142, and 141 sequentially detect the liquid level signal, and the information display unit displays the real-time liquid level height. When the first liquid level gauge 14 detects that the liquid level in the water washing tank 1 has reached the first liquid level height (i.e., the height of the connecting pipe 3), the excess condensate flows into the water storage tank 2 along the connecting pipe 3.

[0054] At this time, level sensors 245, 244, 243, 242, and 241 detect level signals in sequence. When the second level gauge 24 detects that the level in the water storage tank 2 has reached the first level height, the entire equipment changes from the water washing state to the drainage state.

[0055] In the drainage state, the controller first closes the air inlet valve 12 and the air outlet valve 22, and opens the air filling valve 28 to fill the water washing tank 1 and the water storage tank 2 with compressed air. The second pressure sensor 23 detects the pressure in the water storage tank 2 in real time. When the second pressure sensor 23 detects that the pressure in the water storage tank 2 rises to the first pressure threshold (the value of the first pressure threshold is set by the user, preferably 100 kPa), the controller opens the first drain valve 16 and the second drain valve 26 to drain the water.

[0056] In this embodiment, in order to automatically switch back to the water washing state after draining, the controller also controls the closing of the first drain valve 16 and the second drain valve 26, as follows:

[0057] When the first level gauge 14 detects that the liquid level in the washing tank 1 is lower than the second liquid level height, the controller closes the first drain valve 16. The second liquid level height is lower than the first liquid level height, and the second liquid level height is preferably the height of the liquid level sensor 145 at its lowest position or the height of the liquid level sensor 245.

[0058] When the second level gauge 24 detects that the water level in the storage tank 2 is lower than the second water level height, the air filling valve 28 is closed. When the second pressure sensor 23 detects that the pressure in the storage tank 2 has dropped to the second pressure threshold (the value of the second pressure threshold is set by the user and must be less than the first pressure threshold, preferably 0 kPa), the controller closes the second drain valve 26 and opens the air outlet valve 22. When the second pressure sensor 23 detects that the pressure in the storage tank 2 has dropped to the third pressure threshold (the value of the third pressure threshold is set by the user and must be less than the second pressure threshold, preferably -10 kPa), the controller opens the air inlet valve.

[0059] Example 2:

[0060] This embodiment provides a fault self-identification method for an automatic drainage exhaust gas washing treatment device. During startup, operation, and drainage, the method identifies whether any valve is malfunctioning based on changes in pressure signals within the tank under the control status of each valve. Specifically...

[0061] Power-on self-test:

[0062] During the startup process, after the device is powered on, the inlet valve 12, the first drain valve 16, the second drain valve 26, and the outlet valve 22 are closed, and the inflation valve 28 is opened to fill the water storage tank 2 with compressed air. When the pressure measured by the second pressure sensor 23 reaches 100 kPa, the inflation valve 28 is closed to proceed to the next step of testing; if the pressure value measured by the second pressure sensor 23 remains unchanged during the compressed air filling process, it indicates that the inflation valve 28 is faulty.

[0063] The second pressure sensor 23 continuously detects for 30 seconds. If the measured pressure value remains unchanged, it indicates that the intake valve 12, the first drain valve 16, the second drain valve 26, the exhaust valve 22, and the inflation valve 28 are normal. If the measured pressure value decreases, the pressure in the intake pipe 11 is detected by the first pressure sensor 13. If the measured pressure value is positive, it indicates that the intake valve 12 is faulty. Otherwise, it waits for the signal to open the air pump 4 and continuously detects the pressure value of the second pressure sensor 23. If the pressure value decreases at a faster rate and eventually becomes less than 0, it indicates that the exhaust valve 22 is faulty. If the pressure value decreases at a constant rate or the pressure value is always greater than or equal to 0, it indicates that the first drain valve 16 or the second drain valve 26 is faulty.

[0064] When a fault is detected during the self-test of the power-on process, the controller's information display unit will display the corresponding fault code and send a control signal to shut down the air pump. The fault information can be sent to the host computer or other external devices via RS485 communication through the communication unit.

[0065] Operation process detection:

[0066] During the operation, the controller enters the operation detection state 1 minute after receiving the operation signal of the air pump 4.

[0067] If the pressure value detected by the second pressure sensor 23 is less than -60 kPa and the pressure value detected by the first pressure sensor 13 is greater than -5 kPa, it indicates that the intake valve 13 is faulty.

[0068] If the pressure value detected by the second pressure sensor 23 is between -30 kPa and -5 kPa, the pressure value detected by the first pressure sensor 13 is between -20 kPa and -5 kPa, and the pressure value detected by the second pressure sensor 23 is less than the pressure value detected by the first pressure sensor 13, then it indicates that the first drain valve 16 or the second drain valve 26 is faulty.

[0069] If the pressure value detected by the first pressure sensor 13 and the pressure value detected by the second pressure sensor 23 are both between -5 kPa and 0 Pa, it indicates that the air outlet valve 22 is faulty; if the pressure value detected by the first pressure sensor 13 and the pressure value detected by the second pressure sensor 23 are both greater than 0, it indicates that the air filling valve 28 is faulty.

[0070] When a fault is detected during operation, the controller's information display unit will display the corresponding fault code and issue a control signal to shut down the air pump. The fault information can be sent to the host computer or other external devices via RS485 communication through the communication unit.

[0071] Drainage process monitoring:

[0072] During the drainage process, when the liquid level in the water storage tank 2 reaches the first liquid level height, the drainage state is entered. The air inlet valve 12 and air outlet valve 22 are closed, and the air filling valve 28 is opened to fill the water storage tank 2 with compressed air. When the pressure value detected by the second pressure sensor 23 reaches 100 kPa, the air filling valve 28 is closed. If the pressure value detected by the second pressure sensor 23 remains unchanged during the compressed air filling process, it indicates a malfunction in the air filling valve 28.

[0073] The second pressure sensor 23 continuously detects for 30 seconds. If the pressure value remains unchanged, it indicates that the air inlet valve 12, the first drain valve 16, the second drain valve 26, the air outlet valve 22, and the air filling valve 28 are normal. Open the air filling valve 28 to fill the water storage tank 2 with compressed air again, and open the first drain valve 16 and the second drain valve 26 to start draining.

[0074] If the pressure value detected by the second pressure sensor 23 decreases and the pressure value detected by the first pressure sensor 13 increases, it indicates that the intake valve 12 is faulty.

[0075] If the pressure value detected by the second pressure sensor 23 is negative, it indicates that there is a malfunction in the vent valve 22.

[0076] If the pressure value detected by the second pressure sensor 23 decreases and remains positive, it indicates that either the first drain valve 16 or the second drain valve 26 is faulty and cannot be completely closed.

[0077] During the drainage process, if the liquid level detected by the first liquid level gauge 14 does not show a downward trend within 5 seconds, it indicates that the first drain valve 16 is faulty and cannot be opened; if the liquid level detected by the second liquid level gauge 24 does not show a downward trend within 5 seconds, it indicates that the second drain valve 26 is faulty and cannot be opened.

[0078] When a fault is detected during the drainage process, the controller's information display unit will display the corresponding fault code and issue a control signal to shut down the air pump. The fault information can be sent to the host computer or other external devices via RS485 communication through the communication unit.

[0079] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A control method for an automatic drainage exhaust gas washing treatment device, characterized in that, Includes a washing tank, a storage tank, and a controller; The washing tank is equipped with an air inlet pipe at the top and an air inlet valve on the air inlet pipe; the washing tank is equipped with a first level gauge and a first drain pipe at the bottom and a first drain valve on the first drain pipe. The top of the water storage tank is equipped with an air outlet pipe and an air filling pipe. An air outlet valve is installed on the air outlet pipe, and an air pump is connected to the end of the air outlet pipe. An air filling valve is installed on the air filling pipe. A second liquid level gauge is installed on the water storage tank, and a second drain pipe is installed at the bottom. A second drain valve is installed on the second drain pipe. The air inlet pipe is equipped with a first pressure sensor for detecting the pressure inside the air inlet pipe when it is outside the air inlet valve, and the air outlet pipe is equipped with a second pressure sensor for detecting the pressure inside the water storage tank; the washing tank and the water storage tank are connected by a connecting pipe at the first liquid level. The controller is electrically connected to the air inlet valve, the first liquid level gauge, the first drain valve, the air outlet valve, the air filling valve, the second liquid level gauge, the second drain valve, the first pressure sensor, and the second pressure sensor, and controls the opening and closing of the valves according to the detected pressure signal and liquid level signal. The control method of the controller is as follows: When the first level gauge detects that the liquid level in the washing tank has reached the first level height, the excess water flows into the storage tank along the connecting pipe. When the second level gauge detects that the liquid level in the storage tank has reached the first level height, the system enters the drainage state. In the drainage state, the controller closes the air inlet valve and the air outlet valve, and opens the air filling valve to fill the washing tank and the storage tank with compressed air. When the second pressure sensor detects that the pressure in the storage tank has risen to the first pressure threshold, the controller opens the first drain valve and the second drain valve to drain the water. The controller also controls the closing of the first drain valve and the second drain valve, as follows: When the first level gauge detects that the liquid level in the washing tank is lower than the second level height, the controller closes the first drain valve; When the second level gauge detects that the water level in the storage tank is lower than the second level height, the air valve is closed. When the second pressure sensor detects that the pressure in the storage tank drops to the second pressure threshold, the controller closes the second drain valve and opens the air outlet valve. When the second pressure sensor detects that the pressure in the storage tank drops to the third pressure threshold, the controller opens the air inlet valve. The second liquid level is lower than the first liquid level; the first pressure threshold is higher than the second pressure threshold, and the third pressure threshold is lower than the second pressure threshold.

2. The control method for an automatic drainage exhaust gas washing treatment device according to claim 1, characterized in that, The first pressure threshold is 100 kPa, the second pressure threshold is 0, and the third pressure threshold is -10 kPa.

3. The control method for an automatic drainage exhaust gas washing treatment device according to claim 1, characterized in that, The first level gauge includes a plurality of level sensors arranged sequentially along the vertical direction around the periphery of the washing tank.

4. The control method for an automatic drainage exhaust gas washing treatment device according to claim 1 or 3, characterized in that, The second level gauge includes several level sensors arranged sequentially along the vertical direction around the periphery of the water storage tank.

Images