Differential pressure type adjustable pressure switch and gas circuit waterproof and blocking detection system and method

Abstract

The invention belongs to the field of gas circuit detection, and particularly relates to a differential pressure type adjustable pressure switch and a gas circuit waterproof and blocking detection system and method. Gas in the detection gas chamber sequentially passes through the gas-water separator, the drying device and the vacuum pump, and a pressure switch is additionally arranged in the gas detection system, so that when accumulated water in a gas well enters the detection system to influence gas detection, the pressure switch connected with the gas-water separator is automatically turned on due to pressure difference; and external air enters the gas-water separator through the first container and the second container of the pressure switch, so that the pressure is kept balanced, and water is prevented from entering the detection system to block a gas path or damage components in the detection gas chamber. The problem of detection failure of a detection device caused by easy water inlet blockage of a gas detection pipeline is solved.

Description

Technical Field

[0001] The present invention belongs to the field of gas path detection, and particularly relates to a differential pressure adjustable pressure switch, a gas path waterproof and blockage detection system and method. Background Art

[0002] Gas detection devices are usually installed in gas wells to monitor whether gas pipelines leak. Since gas wells are located underground and the environment is relatively humid, a desiccant is arranged at the front stage of the detection device to remove moisture or other impurities in the extracted gas, and components for detecting parameters such as concentration are arranged at the rear stage to detect the extracted gas. To ensure that the target gas can be detected or the accurate gas concentration can be detected, the pipeline for extracting gas in the detection device is usually arranged at the lower end of the detection device. However, after rain, the gas well will flood. When the water level reaches a certain level, water will enter the detection device along with the pipeline when extracting gas. At this time, the function of the desiccant will fail, which not only affects the detection result, but also when the amount of water is large, the water will block the pipeline, affecting gas detection or even directly entering the detection chamber and damaging the electronic devices for detection. The probes for detecting gas are generally expensive and the replacement cost is high. Currently, to solve this problem, a pressure sensor is usually installed in the detection device. If water enters the detection device and causes negative pressure in the detection device, the pressure sensor will detect the pressure in the device in real time. If the negative pressure increases to the set pressure threshold, the detection device will stop pumping gas to avoid water entering the detection chamber and damaging the electrical components in the detection device.

[0003] However, the pressure sensor is an electronic device and is prone to failure in a humid environment. Once it fails, it cannot detect the pressure situation in the detection system in time, and the problem of gas path blockage still exists. This method is not reliable. Moreover, even if the detection device stops pumping gas by judging the pressure, the water that has entered the front stage of the detection device will still flow to the rear stage of the detection device due to negative pressure, which will also damage the components in the rear stage of the monitoring device. The detection devices in gas wells are usually powered by lithium batteries, and the power of the lithium batteries is limited. This real-time detection pressure sensor will consume a part of the electric energy, shortening the service time of the lithium battery, thereby increasing the maintenance frequency of the detection device and raising the maintenance cost. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a differential pressure adjustable pressure switch, a gas path waterproof and blockage detection system and method, so as to solve the problem that the gas detection pipeline is prone to water ingress and blockage, resulting in the failure of the detection device.

[0005] Basic solution provided by the present invention: A differential pressure adjustable pressure switch, comprising a first container and a second container. The bottom of the first container is connected to the bottom of the second container through a pipeline. The upper part of the first container is provided with a first opening communicating with the outside. The upper part of the second container is provided with a second opening, which is used to connect with a pressure switch control device. Liquids are placed in the first container and the second container, and the conduction threshold of the pressure switch is related to the liquid volume.

[0006] Preferably, it further comprises a liquid level sensor, which is used to monitor the liquid level in the second container.

[0007] Preferably, the following relationship exists between the conduction threshold of the pressure switch and the liquid volume:

[0008] P = -2ρgh

[0009] In the formula, P is the conduction threshold of the pressure switch, ρ is the liquid density, g is the acceleration due to gravity, and h is the liquid height in the second container when the pressure switch is in the closed state.

[0010] The principle and advantages of the pressure switch of the present invention are as follows: Connect the openings of the containers to the external gas and the control device respectively, and connect the two containers through a conduit. When in use, when a negative pressure is generated in the control device, since the second container is connected to the control device and the first container is connected to the outside, the external atmospheric pressure will press the liquid in the first container into the second container until all the liquid enters the second container. At this time, the pressure switch conducts. If there is still a pressure difference between the control device and the outside, the external gas will sequentially enter the control device through the first container and the second container to make up the pressure difference and balance the pressure; the more liquid there is in the pressure switch, the greater the conduction threshold of the pressure switch;

[0011] The conduction of the pressure switch is realized by using the pressure difference and the liquid in the container. Compared with the prior art solution of using electronic devices to detect pressure, this pressure switch will not be damaged due to environmental humidity and has high reliability; and by changing the liquid volume in the container to adjust the conduction threshold of the pressure switch, the threshold can be adjusted according to different application scenarios and device parameters, with strong adaptability and wide application range;

[0012] By setting a liquid level sensor, the working state of the pressure switch can be judged by detecting the liquid level of the container, which is convenient for monitoring the working state of the pressure switch and improving the intelligence level of the pressure switch; at the same time, compared with the prior art, the pressure switch does not need to detect the pressure in real time to control the device, and only needs to set a longer detection period, consuming less power.

[0013] Basic solution provided by the present invention: An air circuit waterproof and blockage detection system, including a detection control device, a drying device, and a detection air chamber. The detection control device includes a controller and a vacuum pump. A detection sensor is arranged in the detection air chamber. The air outlet of the detection air chamber communicates with a gas well, and the air inlet is connected to the air outlet of the vacuum pump through a pipeline. The air inlet of the vacuum pump is connected to the air outlet of the drying device through a pipeline. The air inlet of the drying device is connected to the air outlet of a gas-water separator through a pipeline. The gas-water separator includes a first air inlet and a second air inlet. The first air inlet is connected to a pipeline for extracting detection gas, and the second air inlet is connected to the second opening of a pressure switch through a pipeline. The detection sensor and the vacuum pump are electrically connected to the controller, and the controller is communicatively connected to a gas well management system.

[0014] Preferably, the detection sensor includes a gas concentration sensor and a humidity sensor.

[0015] Preferably, the drying device includes a desiccant placement area and a desiccant dissolution storage area, and a porous partition is arranged between the desiccant placement area and the desiccant dissolution storage area.

[0016] The principle and advantages of the system of the present invention are as follows: The gas entering the detection air chamber sequentially passes through the gas-water separator, the drying device, and the vacuum pump. The controller controls the vacuum pump to extract the detection gas. The detection gas enters the gas-water separator through the first air inlet, removing most of the water, and then passes through the drying device to remove the water vapor of the detection gas again, ensuring the accuracy of gas detection. Among them, the second air inlet of the gas-water separator is connected to a pressure switch. When there is a large amount of water in the gas well, causing the gas-water separator to generate negative pressure and resulting in air circuit blockage, the pressure switch is turned on due to the pressure difference between the two, and external air enters the gas-water separator through the pressure switch, preventing more water from being pumped into the air circuit and causing blockage or damage to the detection device. Compared with the prior art system that uses a pressure sensor to control the vacuum pump to stop to prevent blockage, the differential pressure type pressure switch has higher reliability and will not fail due to environmental humidity, improving the reliability of the entire system. At the same time, after the pressure switch tube is turned on, even if the vacuum pump is still running or not stopped in time, the water in the gas separator will not increase anymore, avoiding water vapor from entering the front section of the air circuit system and thus damaging the relatively expensive detection equipment. The pressure switch is provided with a liquid level sensor for monitoring the working state of the pressure switch, thereby monitoring the negative pressure in the gas-water separator and the water volume in the gas well, facilitating the management personnel to take measures according to the water accumulation situation. And compared with the prior art, it is not necessary to continuously monitor the pressure of the gas-water separator in real time to control the detection system. Only a longer detection period needs to be set, consuming less power, and thus having lower maintenance costs.

[0017] Preferably, the gas concentration is monitored by a gas concentration sensor to grasp the gas leakage situation of the gas well. The humidity of the gas and the humidity of the gas chamber are detected by a humidity sensor, which facilitates timely maintenance and prevents major losses.

[0018] The basic solution provided by the present invention: a gas path waterproof and blockage detection method

[0019] Set the conduction threshold of the pressure switch according to the detection system parameters;

[0020] The controller controls the vacuum pump to operate, and extracts the detection gas through the first air inlet. If water enters the gas-water separator and forms a negative pressure in the gas-water separator, the liquid level in the first container of the pressure switch drops. When all the liquid in the first container enters the second container, the pressure switch conducts;

[0021] After the pressure switch conducts, if there is still negative pressure in the gas-water separator, the gas outside the detection system enters the gas-water separator through the first container and the second container until the internal pressure of the gas-water separator is balanced with the external air pressure;

[0022] When the accumulated water in the gas well decreases, the water inside the gas-water separator flows out through the first air inlet, increasing the negative pressure in the gas-water separator. The air outside the detection system enters the gas-water separator from the first air inlet or the second air inlet, reducing the negative pressure in the gas-water separator, and discharging all the water inside the gas-water separator. At the same time, the liquid in the second container is pressed into the first container, and the liquid levels of the first container and the second container are the same, and the pressure switch closes.

[0023] Preferably, when the continuous conduction time of the pressure switch exceeds the set conduction duration, the controller sends an alarm message to the gas well management system.

[0024] The principle and advantages of the method of the present invention are as follows: Set the conduction threshold of the pressure switch according to different detection systems and application scenarios, and flexibly use the pressure switch; Connect the second outlet of the pressure switch to the second air inlet of the gas-water separator. When there is negative pressure in the gas-water separator, the liquid level of the liquid in the pressure switch container changes due to the pressure difference. When all the liquid in the pressure switch enters the second container, the pressure switch conducts. If the negative pressure in the gas-water separator still exists, then the external gas enters the gas-water separator through the pressure switch to make up for the negative pressure until the pressure in the gas-water separator is balanced with the external pressure, thereby preventing the accumulated water at the lower part of the gas well from entering the gas-water separator, causing gas path blockage and damage to the internal electrical components of the detection system; Set the pressure switch, and there is no need for electrical components to detect the internal pressure of the gas-water separator in real time. Only a relatively long cycle detection is required, which not only saves electricity but also reduces the maintenance cost.

[0025] Preferably, the liquid level of the pressure switch container is detected by a liquid level sensor to obtain the working state of the pressure switch. When the conduction time is too long, an alarm message is sent so that the management personnel can timely obtain the blockage situation inside the gas well and take corresponding measures. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic structural diagram of the system of the present invention;

[0027] Figure 2 It is a closed state diagram of the pressure switch of the present invention;

[0028] Figure 3 It is a conduction state diagram of the pressure switch of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following is a further detailed description through specific embodiments:

[0030] The specific implementation process is as follows: Refer to Figures 1 to 3 , a differential pressure adjustable pressure switch, including a first container and a second container. The first container and the second container have the same structure. In this embodiment, it is preferably a tank with a circular cross-section. The bottom of the first container is connected to the bottom of the second container through a pipeline. The upper part of the first container is provided with a first opening communicating with the outside. The upper part of the second container is provided with a second opening for connecting to a pressure switch control device. Liquids are placed in the first container and the second container. In this embodiment, the liquid in the container is water. The conduction threshold of the pressure switch is positively correlated with the liquid volume. By changing the liquid volume in the container, the conduction threshold can be adjusted to be applicable to different pressure switch control devices;

[0031] The relationship between the conduction threshold of the pressure switch and the liquid volume is as follows:

[0032] P = -2ρgh

[0033] In the formula, P is the conduction threshold of the pressure switch, ρ is the liquid density, g is the acceleration due to gravity, and h is the liquid height in the second container when the pressure switch is in the closed state.

[0034] It further includes a liquid level sensor. The liquid level sensor is installed outside the second container and is used to monitor the liquid level in the second container. When the liquid level sensor detects that the liquid level in the second container reaches the set position, it sends a message to the controller of the control device.

[0035] An air circuit waterproof and blockage detection system for a differential pressure type adjustable pressure switch, comprising a detection control device, a drying device, and a detection air chamber. The detection control device includes a controller and a vacuum pump. The controller is a single-chip microcomputer, preferably a single-chip microcomputer with a main control chip of stm32 in this embodiment. The model of the vacuum pump in this embodiment is G4BW2473S. A detection sensor is arranged in the detection air chamber. The air outlet of the detection air chamber communicates with a gas well, and the air inlet is connected to the air outlet of the vacuum pump through a pipeline. The air inlet of the vacuum pump is connected to the air outlet of the drying device through a pipeline. The air inlet of the drying device is connected to the air outlet of a gas-water separator through a pipeline. The gas-water separator includes a first air inlet and a second air inlet. The first air inlet is connected to a pipeline for extracting detection gas, and the second air inlet is connected to a second opening of the pressure switch through a pipeline. The detection sensor, the vacuum pump are electrically connected to the controller, and the controller is communicatively connected to a gas well management system.

[0036] The detection sensor includes a gas concentration sensor and a humidity sensor. The gas concentration sensor is used to detect the gas concentration, and the humidity sensor is used to assist in the detection of the gas concentration and detect the humidity of the detection air chamber. The model of the gas concentration sensor is preferably Honeywell C03-0962-000, and the model of the humidity sensor is preferably DHT11.

[0037] The controller includes a communication module. The controller is communicatively connected to the gas well management system through the communication module. The communication module is NB-IoT or 5G wireless communication, preferably NB-IoT in this embodiment.

[0038] A liquid level sensor arranged on the pressure switch is connected to the controller. The controller judges whether the pressure switch is turned on by receiving the signal of the liquid level sensor. When the conduction time of the pressure switch exceeds the set conduction duration, the controller sends an alarm to the gas well management system, so that the staff can know in time that there is accumulated water in the gas well, which is convenient for the staff to manage the gas well.

[0039] The drying device includes a desiccant placement area and a desiccant dissolution storage area. A porous partition is arranged between the desiccant placement area and the desiccant dissolution storage area.

[0040] A method for an air circuit waterproof and blockage detection system

[0041] Set the conduction threshold of the pressure switch according to the detection system parameters; the detection system parameters include the ultimate pressure, pumping speed, power of the vacuum pump, as well as the volume of the gas-water separator, the pipe diameter of the pipeline, etc.;

[0042] The controller controls the operation of the vacuum pump, extracts the detection gas through the first air inlet. If water enters the gas-water separator and creates a negative pressure inside the gas-water separator, the liquid level in the first container of the pressure switch drops. When all the liquid in the first container enters the second container, the pressure switch conducts electricity.

[0043] After the pressure switch conducts electricity, if there is still a negative pressure inside the gas-water separator, the gas outside the detection system enters the gas-water separator through the first container and the second container to reduce the negative pressure until the internal pressure of the gas-water separator is balanced with the external air pressure.

[0044] When the accumulated water in the gas well decreases, the water inside the gas-water separator flows out through the first air inlet due to gravity, increasing the negative pressure in the gas-water separator. The air outside the detection system enters the gas-water separator from the first air inlet or the second air inlet to supplement the reduced pressure in the gas-water separator, reducing the negative pressure in the gas-water separator. All the water in the gas-water separator is discharged due to pressure and gravity, and the detection system can normally extract the detection gas. At the same time, the liquid in the second container is pressed into the first container until the liquid levels in the first container and the second container are the same, and the pressure switch closes.

[0045] When the continuous conduction time of the pressure switch exceeds the set conduction duration, the controller sends an alarm message to the gas well management system. The conduction duration is 1 - 2.5 h. In this embodiment, the conduction duration is preferably 1.5 h.

[0046] The above are only embodiments of the present invention. Specific structures and common knowledge such as characteristics well known in the art are not described in detail here. Those of ordinary skill in the art know all the common technical knowledge in the technical field to which the invention belongs before the application date or the priority date, can know all the existing technologies in this field, and have the ability to apply the conventional experimental means before this date. Those of ordinary skill in the art can, under the inspiration given in this application, combine their own abilities to improve and implement this solution. Some typical well-known structures or well-known methods should not become an obstacle for those of ordinary skill in the art to implement this application. It should be noted that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can still be made, and these should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners described in the specification can be used to explain the content of the claims.

Claims

1. A differential pressure adjustable pressure switch, characterized in that: It includes a first container and a second container, the bottom of the first container is connected to the bottom of the second container through a pipeline, the first container is provided with a first opening on the top to communicate with the outside, the second container is provided with a second opening on the top, the second opening is used to connect with a pressure switch control device, liquid is placed in the first container and the second container, and the conduction threshold of the pressure switch is related to the amount of liquid.

2. The differential pressure adjustable pressure switch according to claim 1, characterized in that: It also includes a liquid level sensor, which is used to monitor the liquid level of the liquid in the second container.

3. The differential pressure adjustable pressure switch according to claim 1, characterized in that: The conduction threshold of the pressure switch and the amount of liquid have the following relationship: P=-2ρgh Wherein, P is the conduction threshold of the pressure switch, ρ is the liquid density, g is the acceleration of gravity, and h is the height of the liquid in the second container when the pressure switch is in the closed state.

4. A gas circuit waterproof and blockage detection system for a differential pressure adjustable pressure switch according to any one of claims 1 to 3, comprising a detection control device, a drying device, and a detection air chamber, wherein the detection control device comprises a controller and a vacuum pump, and a detection sensor is arranged in the detection air chamber, characterized in that: The air outlet of the detection air chamber is communicated with the gas well, and the air inlet is connected to the air outlet of the vacuum pump through a pipeline. The air inlet of the vacuum pump is connected to the air outlet of the drying device through a pipeline. The air inlet of the drying device is connected to the air outlet of a gas-water separator through a pipeline. The gas-water separator includes a first air inlet and a second air inlet. The first air inlet is connected to a pipeline for extracting detection gas, and the second air inlet is connected to the second opening of the pressure switch through a pipeline. The detection sensor, vacuum pump and controller are electrically connected, and the controller is communicatively connected to a gas well management system.

5. The air circuit waterproofing and blockage detection system according to claim 4, characterized in that: The detection sensors include a gas concentration sensor and a humidity sensor.

6. The air circuit waterproofing and blockage detection system according to claim 4, characterized in that: The drying device comprises a desiccant placement area and a desiccant dissolving storage area, and a porous partition is arranged between the desiccant placement area and the desiccant dissolving storage area.

7. A method for the air circuit waterproofing and blockage detection system of claim 4, characterized in that: Set the conduction threshold of the pressure switch according to the detection system parameters; The controller controls the vacuum pump to extract the detection gas through the first air inlet. If water enters the gas-water separator to form a negative pressure in the gas-water separator, the liquid level in the first container of the pressure switch will drop. When all the liquid in the first container enters the second container, the pressure switch will be turned on. When the pressure switch is turned on, if there is still negative pressure in the gas-water separator, the gas outside the detection system enters the gas-water separator through the first container and the second container until the internal pressure of the gas-water separator is balanced with the external air pressure; When the water accumulation in the gas well decreases, the water inside the gas-water separator flows out from the first air inlet, increasing the negative pressure in the gas-water separator. The air outside the detection system enters the gas-water separator from the first air inlet or the second air inlet, reducing the negative pressure in the gas-water separator and causing all the water inside the gas-water separator to be discharged. At the same time, the liquid in the second container is pressed into the first container. The liquid levels in the first container and the second container are the same, and the pressure switch is closed.

8. The method for detecting air circuit waterproofing and blockage according to claim 7, characterized in that: When the continuous conduction time of the pressure switch exceeds the set conduction time, the controller sends an alarm message to the gas well management system.

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