A groundwater pollution detection system and method

Abstract

The present invention discloses a groundwater pollution detection system and method, belonging to the field of groundwater detection technology, the system includes a filter tube and a central tube, and also includes a machine well pump, a water outlet pipe, and a water storage device, the water storage device includes a first water storage device and a second water storage device, the first water storage device is connected in series to the water outlet pipe, and the second water storage device is connected to the end of the water outlet pipe; the second water storage device is provided with a liquid level detection device, the first water storage device is provided with a first check valve on the inlet side, and the first water storage device is provided with a second check valve on the outlet side; the first water storage device is detachably connected to the water outlet pipe or the first water storage device is provided with a discharge pipeline that can be opened and closed, and the method is a method for realizing groundwater pollution detection based on the system. The system and method can not only ensure the sampling efficiency of the sampling personnel, but also ensure the sampling quality.

Description

Technical Field

[0001] The present invention relates to the field of groundwater detection technology, and in particular to a groundwater pollution detection system and method. Background Art

[0002] Groundwater pollution detection usually detects the types, concentrations and changing trends of harmful substances in groundwater. The purpose is to evaluate and understand the groundwater pollution situation and pollution development trend. The methods usually used include laboratory detection methods and online detection methods. Among them, the laboratory detection method is to analyze and process the test samples in the laboratory after obtaining them. It has the characteristics of accurate detection results and a large number of detectable items. It is particularly suitable for obtaining deep water quality conditions for the purpose of water quality management. The online detection method is generally achieved through water pollution detection sensors installed in logging wells (also known as detection wells) for a long time. The sensors can detect the water quality in the well at any time, so the test results can be obtained immediately. However, due to the influence of sensor types and environmental factors on sensor test results, the accuracy of the detection results and the number of detectable items are usually not as good as those of laboratory detection methods. It is particularly suitable for regional management and control based on real-time water quality change monitoring results.

[0003] Sampling wells or detection wells for groundwater pollution detection include special logging wells, industrial water wells, and civil water wells selected or arranged according to factors such as groundwater hydrological characteristics and the distribution of pollution sources. In the laboratory detection method of groundwater pollution, it is necessary to obtain the test samples from the sampling points. In the online detection method of groundwater pollution, it is necessary to install water pollution detection sensors in the detection wells. In the prior art, for the logging wells used as detection wells and sampling wells, the functions of the groundwater pollution detection system include real-time detection of the water quality in the logging wells and obtaining test samples for the laboratory from the logging wells. For the acquisition of test samples, in order to obtain samples located in different water layers and reduce the number of logging wells, there are technical means to obtain test samples from different water layers of a logging well. For online logging detection, in order to obtain the water quality of different water layers, there are technical means to set water pollution detection sensors in different water layers of a logging well.

[0004] Groundwater pollution detection can be used to timely discover pollution problems and provide a scientific decision-making basis for the prevention and control of groundwater pollution. Therefore, further optimizing groundwater pollution detection technology is of positive significance. Summary of the invention

[0005] In view of the above-mentioned problem of optimizing groundwater pollution detection technology, the present invention provides a groundwater pollution detection system and method. The system and method can not only ensure the sampling efficiency of sampling personnel, but also ensure the sampling quality.

[0006] In view of the above problems, a groundwater pollution detection system and method provided by the present invention solves the problems through the following technical points: a groundwater pollution detection system, comprising a filter tube and a central tube coaxially arranged in the filter tube, and also comprising a machine-well pump arranged in the central tube, a water outlet pipe connected to the machine-well pump, and a water storage device connected to the outlet side of the water outlet pipe, wherein the filter tube and the central tube are both pipes with filter holes arranged on the pipe wall, and the water storage device comprises a first water storage device and a second water storage device, wherein the first water storage device is connected in series to the water outlet pipe, and the second water storage device is connected to the end of the water outlet pipe, and the first water storage device is a component of the pipeline between the machine-well pump and the second water storage device;

[0007] The second water storage device is provided with a liquid level detection device for detecting the liquid level in the second water storage device, a first one-way valve is provided on the water outlet pipe on the inlet side of the first water storage device, and a second one-way valve is provided on the water outlet pipe on the outlet side of the first water storage device, the conduction direction of the first one-way valve is to allow the water outlet pipe to inject water into the first water storage device, and the conduction direction of the second one-way valve is to allow the water outlet pipe to inject water into the second water storage device;

[0008] The first water storage device is detachably connected to the water outlet pipe or the first water storage device is provided with an openable and closable discharge pipeline;

[0009] When the first water storage device is detachably connected to the water outlet pipe, both ends of the first water storage device are connected in series to the water outlet pipe through a flexible joint;

[0010] When the first water storage device is provided with a discharge pipeline, the upper end of the first water storage device is provided with an openable and closable pressure equalizing hole.

[0011] The above scheme is applied to groundwater pollution detection during its implementation. Specifically, it can be used to collect test samples for groundwater pollution detection from logging wells, so as to obtain more pollution detection project test results and more accurate test results on the ground or in the testing laboratory.

[0012] When the detection system is in use, the filter tube and the center tube are placed in the well logging (detection well), the pump is installed in the center tube, and the water storage device is arranged above the ground, so that the groundwater of the well logging enters the filter tube through the filter holes on the filter tube, and the groundwater in the filter tube enters the center tube through the filter holes on the center tube, which enables the pump located in the center tube to pump groundwater to the water storage device through the outlet pipe. The filter tube not only serves as a support tube for the well logging to maintain the structural stability of the well logging, but also forms a protective cover located outside the pump together with the center tube when the pump is working, isolating the disturbance caused to the well logging wall by the sudden shaking of the pump when the pump is started, and expanding the water inlet area of ​​the center tube and the side wall of the filter tube after the pump is started through the filter holes on the center tube and the filter tube, so as to avoid the pump from taking water at a concentrated position in the well logging.

[0013] Compared with the existing common water pollution well logging detection system, the structural features of this solution include the structural design of the water storage device to obtain a differentiated detection sample collection method. When in use, the machine well pump is started at a set time or according to a control instruction to pump groundwater in the well from the central pipe into the water storage device. Before the water storage device collects the water from the machine well pump, if there is residual water in the second water storage device, the residual water in the second water storage device is discharged in advance through a discharge pipeline connected to the second water storage device. After the discharge is completed, the discharge pipeline is cut off so that all the water from the end of the outlet pipe can be collected by the second water storage device. When the water storage device collects the water from the machine well pump, the water pumped by the machine well pump passes through the first one-way valve, the first water storage device, and the second one-way valve in sequence and enters the second water storage device. When the liquid level is passed through When the detection device detects that the liquid level in the second water storage device reaches or exceeds the set liquid level, the machine well pump stops pumping water; after the machine well pump stops pumping water, the inlet side and the outlet side of the first water storage device are cut off by the first one-way valve and the second one-way valve, and the water retained in the first water storage device is used as a detection sample. When the first water storage device is detachably connected to the water outlet pipe, after the live joint is removed, the detection sample is collected from the first water storage device. The detection sample collection method is to discharge the water in the first water storage device on site, and collect these waters as detection samples for subsequent water pollution project detection, or after blocking both ends of the first water storage device, carry the first water storage device to the laboratory, and then discharge the water in the first water storage device, and collect these waters as detection samples for use in subsequent detection projects;When the first water storage device is provided with a discharge pipeline, the test sample is collected from the first water storage device through the discharge pipeline, and the pressure equalizing hole is opened during the collection process. The pressure equalizing hole can not only improve the efficiency of the discharge pipeline in discharging the test sample, but also, because the first water storage device can complete the pressure equalization independently of the discharge pipeline in the discharge process, compared with the discharge pipeline inhaling air process, a large number of bubbles will be formed in the collected sample. The pressure equalizing hole only allows the liquid surface position in the first water storage device to have the opportunity for the collected sample to contact with the air. Therefore, the above pressure equalizing hole is beneficial to reducing the opportunity for the test sample to contact with the air during the sampling process. The set liquid level is: when the water body in the second water storage device reaches the set liquid level, the water body of the second water storage device The volume is greater than or equal to the sum of the volume of water that can be retained in the outlet pipe and the volume of water that can be retained in the first water storage device. In this way, when the water in the second water storage device reaches the set liquid level, it means that the water that may be retained in the outlet pipe before the pump is started and the water retained in the first water storage device are squeezed into the second water storage device. At this time, after the pump is stopped, under the action of the two shut-off valves, the water retained in the first water storage device at this time can be the water extracted from the central pipe. When this part of water is used for pollution project detection, the detection results can accurately reflect the current groundwater pollution situation. After the test sample is collected through the first water storage device, the test sample pollution detection is completed in the laboratory. ;

[0014] As introduced in the above method of using the water storage device, the second water storage device and the liquid level detection device are used to calibrate that the water in the first water storage device when the machine-well pump is stopped is no longer the water previously retained in the outlet pipe and the first water storage device, or the water in the first water storage device when the machine-well pump is stopped is the water retained in the first water storage device after pre-flushing the outlet pipe and the first water storage device under the action of the water pumped by the machine-well pump. Therefore, from the perspective of the reliability of the source of groundwater sampling and detection samples and the possible introduction of water quality interference factors in the groundwater pumping process, this scheme is beneficial to the sampling quality of the detection samples.

[0015] On the other hand, when the machine well pump stops operating, the first one-way valve and the second one-way valve cut off the front and rear ends of the first water storage device. At this time, the water retained in the first water storage device is enclosed in a closed space. This not only prevents the backflow of this part of the water body, but also prevents this part of the water body from being contaminated by external factors while waiting for sampling. On the other hand, the structural characteristics of the water storage device provide the water body in the first water storage device with an anti-external pollution protection function. In this way, the first water storage device can store test samples before the arrival of the sample collection personnel. It is only necessary to ensure that there are sufficient inspection samples in the first water storage device after the arrival of the collection personnel. Therefore, from the perspective of protecting the test samples and ensuring the sampling efficiency, this scheme is suitable for small-flow pumping water bodies by machine well pumps. This inspection sample pumping method can avoid disturbances to well logging during the pumping of groundwater and affect the quality of groundwater sampling, and has the characteristic of ensuring the sampling efficiency of the sampling personnel.

[0016] In a specific embodiment, the number of the first water storage devices is greater than or equal to 2. Each time an inspection sample is obtained from the system, the water retained in the second water storage device is drained, and the first water storage device on the current water storage device is removed and brought back to the laboratory. In a laboratory environment, the test sample is obtained from the first water storage device and water pollution detection is completed. The first water storage device is used as a test sample transfer container to reduce the number of transfers in the process of obtaining the test sample, reduce the interference with the water quality of the test sample during the transfer process, and improve the convenience of sampling the test sample. A new first water storage device is installed on the water storage device to prepare for the next test sample.

[0017] In a specific embodiment, the first water storage device is detachably connected to the water outlet pipe, and at the end of the water outlet pipe, a first one-way valve, a flexible joint, a first cut-off valve, a first water storage device, a second cut-off valve, a flexible joint and a second one-way valve are sequentially connected in series on the water outlet pipe;

[0018] The first water storage device is a tubular container with pipe openings at both ends, and the first water storage device is connected to the first shut-off valve and the second shut-off valve through the pipe openings at the ends.

[0019] In this solution, the first shutoff valve, the first water storage device, and the second shutoff valve form a water intake module, that is, by operating the flexible joints at both ends of the water intake module, the water intake module can be detached from the water storage device. Based on such a structure, the test sample sampling process can be: when the machine well pump is started and it is determined by the liquid level detection device that the first water storage device has completed water storage, the machine well pump is turned off. After the sampling personnel arrive at the scene, they close the first shutoff valve and the second shutoff valve, remove the flexible joints at both ends of the water intake module, separate the water intake module storing the test sample from the system, and connect the new water intake module in series to the water outlet pipe through the flexible joint, check the first shutoff valve and the second shutoff valve, so that the first shutoff valve and the second shutoff valve are both in an open state, and then take the removed water intake module back to the laboratory. When the test sample is needed, the water intake module is erected and the first shutoff valve and the second shutoff valve are opened, and the upper end of the water intake module is used as the air inlet end and the lower end is used as the water outlet end, so as to discharge the test sample from the first water storage device in a manner that reduces the chance of contact between the water body and the air. The first water storage device adopts a tubular container. The purpose is: such a first water storage device has a structural form that during the water intake and discharge process of the first water storage device, the water located in the first water storage device can be pushed forward as much as possible under the action of the water intake from the rear and discharged from the front of the first water storage device. In this way, after the machine well pump stops operating, the water originally retained in the detection system and the water used as flushing water in the early stage of starting the machine well pump can be discharged from the first water storage device as much as possible, thereby ensuring the quality of the sample retention for detection of this detection system.

[0020] In a specific embodiment, the first water storage device is a strip-shaped flat tube with an enlarged middle portion, the pipe openings at both ends of the first water storage device are located at the center of the width direction of the first water storage device, the pipe openings of the first water storage device are connected to the enlarged structure in the middle of the first water storage device through a reducing section, and a water distribution assembly is provided in the pipe opening of the first water storage device connected to the first shut-off valve, and the water distribution assembly is used to evenly distribute the water from the first water storage device on the pipe cross-section of the first water storage device.

[0021] In this solution, the first water storage device is a flat tube structure with a bulged middle part, which is used to ensure the volume of the first water storage device, and the end of the first water storage device has a smaller pipe opening to facilitate its series connection on the water outlet pipe. When in use, the installation posture of the first water storage device is a flat posture. The structural features of the first water storage device are: it has a variable diameter section at both ends, a bulged structure in the middle, and a pipe opening located in the center of the width direction, which is used to make the first water storage device perpendicular to the water flow direction ( Figure 2On the pipe cross section (in the direction indicated by the arrow in the middle), the flow velocity at each position of the cross section is relatively uniform, so as to avoid the water in the first water storage device not being fully replaced during the water flow process due to the existence of dead angles in the first water storage device. The water distribution assembly is used to further constrain the flow field state in the first water storage device when the water is passed, so that the water entering the first water storage device when the water is taken in can be evenly distributed on the pipe cross section, so that the water at each position in the first water storage device has a forward-flowing state. Therefore, the water distribution assembly is a water distribution structure arranged based on the configuration of the first water storage device, which is used to forcibly constrain the water flow state in the first water storage device.

[0022] In a specific embodiment, the water distribution assembly is a block structure having a plurality of water distribution holes thereon, and the block structure is embedded in the pipe hole on the inlet side of the first water storage device, wherein the opening of one end of the water distribution hole faces the outside of the first water storage device, and the opening of the other end faces the inside of the first water storage device, and the openings of these water distribution holes facing the inside of the first water storage device have multiple directions, so that the water entering the first water storage device through different water distribution holes has different flow directions, thereby achieving the purpose of uniform flow rate and flow velocity at various positions on the pipe cross section of the first water storage device.

[0023] In a specific embodiment, the liquid level detection device includes a liquid level tube connected to the second water storage device, a float arranged in the liquid level tube, a holder clamped on the liquid level tube, and a magnetic detector installed on the holder, wherein a magnet is arranged in the float, and the position of the holder in the height direction of the liquid level tube is adjustable.

[0024] This solution is used to solve the problem of front-end drainage under different machine-well pump water intake depths, and is used to ensure the sampling quality of the test samples in the first water storage device. Specifically, for different machine-well pump setting depths, it is necessary to configure the outlet pipe to have a length that adapts to the depth. When the same size of outlet pipe and the size of the first water storage device are used, before the machine-well pump is shut down, the amount of front flushing water discharged and the amount of retained water discharged in the outlet pipe are related to the length of the outlet pipe. When the machine-well pump is deeper, the outlet pipe is longer, and more water needs to be discharged to the second water storage device before the test samples are stored in the first water storage device. When the machine-well pump is shallower, the outlet pipe is shorter, and less water needs to be discharged to the second water storage device before the test samples are stored in the first water storage device. Using the above solution, the position of the magnetic induction zone of the liquid level detection device is adjusted by adjusting the position of the holder on the liquid level tube. When the holder is in a higher position, it is only when the float carries the magnet with the second water storage device. The liquid level is detected by the magnetic detector only when it rises to a higher position. At this time, there is more water in the second water storage device, which means that more water is discharged from the end of the water outlet pipe. On the contrary, when the position of the holder on the liquid level pipe is low, the float carries the magnet and is detected by the magnetic detector when the liquid level of the second water storage device rises to a lower position. At this time, there is less water in the second water storage device, which means that less water is discharged from the end of the water outlet pipe. This solution is essentially a float level gauge. Compared with other methods such as detecting the water output at the end of the water outlet pipe through a flow meter and detecting the liquid level of the second water storage device through capacitance value, pressure, ultrasonic wave, radar wave, etc., it not only has low implementation and maintenance costs and the detection results are not easily interfered with, but also can adjust the drainage volume according to specific application scenarios. The matching adjustment can be completed by moving the holder on the liquid level pipe, and the magnetic detector plays the role of a switch in place. Therefore, this solution also has the characteristic of simple debugging. In specific applications, the maximum retained water volume of the outlet pipe and these pipes can be calculated based on the length of the outlet pipe currently used and the size of the first water storage device and other pipes, and then the minimum height of the holder on the liquid level pipe can be calculated based on the volume, and then the holder can be adjusted so that the actual height of the holder is equal to or higher than the minimum height, so as to ensure that the outlet pipe of the first water storage device has the minimum drainage volume before the test sample is stored to ensure the quality of the water in the first water storage device. The working principle of the liquid level detection device is as follows: when the float carries the magnet and moves toward the magnetic detector on the holder, the magnetic flux detected by the magnetic detector as a fluxmeter changes. When the magnetic flux detection result reaches the set threshold, it means that the float rises to a higher position with the liquid level of the second water storage device. That is, this scheme uses the method that the position of the magnet changes with the liquid level height in the second water storage device and the magnetic detector obtains different detection results according to the position of the magnet to determine whether the liquid level in the second water storage device has reached the required height.

[0025] In a specific embodiment, the filter tube and the central tube are both provided with a baffle group, the baffle group on the filter tube includes two first baffles arranged at different positions of the filter tube, each first baffle is provided with a central hole, and the central tube passes through each first baffle through the central hole;

[0026] The partition group on the filter tube divides the filter tube into a first water accumulation chamber and a first isolation chamber arranged along the axis of the filter tube, wherein the first isolation chamber is a chamber surrounded by two first partitions of the partition group on the filter tube, the first water accumulation chamber is a chamber outside the partition group on the filter tube, and the filter holes on the filter tube are located on the side wall of the first water accumulation chamber;

[0027] The baffle group on the central tube includes two second baffles arranged at different positions of the central tube, and the baffle group on the central tube divides the central tube into a second water accumulation chamber and a second isolation chamber arranged along the axis of the central tube, wherein the second isolation chamber is a chamber on the central tube surrounded by two second baffles of the baffle group, the second water accumulation chamber is a chamber outside the baffle group on the central tube, and the filter hole on the central tube is located on the side wall of the second water accumulation chamber;

[0028] The second isolation chamber spans the first isolation chamber, and both the first isolation chamber and the second isolation chamber are sealed chambers. Each first water accumulation chamber has a second water accumulation chamber that is connected to the first water accumulation chamber through a filter hole on a central tube. Each second water accumulation chamber is provided with a machine well pump, and each machine well pump is equipped with a water outlet pipe and a water storage device.

[0029] In this solution, the space in the filter tube is divided into first water accumulation chambers arranged along the axial interval by using two first partitions included in the partition group on the filter tube, that is, there is a first isolation chamber of a certain length between two adjacent first water accumulation chambers. When used for groundwater sampling at different depths, the mutual interference of groundwater at different depths can be reduced. From the perspective of groundwater sampling depth, the groundwater collected from each first water accumulation chamber is more representative. In this solution, the central tube is divided into second water accumulation chambers arranged along the axial interval by using two second partitions included in the partition group on the central tube, and the second isolation chamber is used to make the second water accumulation chamber and the first water accumulation chamber position fit, and establish a one-to-one connection relationship between the second water accumulation chamber and the first water accumulation chamber. At the same time, the water storage capacity of the central tube is reduced by the second isolation chamber. When the central tube needs to be lifted to maintain the well pump and sensor module installed thereon, since the second isolation chamber is a cavity in the central tube, such a cavity layout can reduce the force required to lift the central tube, thereby achieving the purpose of improving the convenience of repair of the system.

[0030] In a specific embodiment, for two or more second water accumulation chambers distributed up and down, the water outlet pipe configured for the machine well pump in the lower second water accumulation chamber passes through the second partition above, extends through the inner space of the central tube to the side inlet and is connected to the water storage device, and the machine well pumps at different heights are connected in series through steel wire ropes, and the positions where the steel wire ropes and the water outlet pipes cooperate with the second partition are sealed so that the second water accumulation chambers at different heights in the central tube can be completely isolated from each other. The sealed connection can be: for the wire rope and the water outlet pipe, after each of them passes through the second partition, the gap between each of them and the second partition is sealed with flexible glue to avoid sealing failure at these positions due to vibration during the operation of the system.

[0031] In a specific embodiment, each second water accumulation chamber is provided with a sensor module for detecting groundwater contamination;

[0032] Each second water accumulation chamber is provided with an operation window located on the side wall of the central tube. The operation window is covered by a cover plate, and the cover plate is detachably connected to the side wall of the central tube.

[0033] In this solution, the sensor module is used to detect the water quality of groundwater in the second water storage chamber online. The specific method of use is: use the detection results of the sensor module to provide a qualitative reference for the groundwater pollution situation. When the detection result is contaminated and further quantitative detection of pollution is required, use the water storage device to obtain laboratory test samples to complete the detection of more items and obtain more accurate test results. After opening, the operation window serves as an operation window for installing and maintaining the machine well pump and the liquid level detection device, and as an operation window for completing the connection between the outlet pipe and the outlet of the machine well pump and using flexible glue to seal the gap. After completing the relevant operations through the second water storage chamber, the operation window is covered by the cover plate, and then the center tube can be placed in the filter tube. In the specific implementation, in order to increase the water inlet area of ​​the second water storage chamber, filter holes are set on the cover plate and the side wall of the second water storage chamber outside the cover plate.

[0034] In a specific embodiment, the first baffle includes an outer ring, an intermediate ring and an inner ring, all of which are annular structures. The outer ring, the intermediate ring and the inner ring are all coaxial with the filter tube. The outer side of the inner ring is connected to the inner side of the intermediate ring, the outer side of the intermediate ring is connected to the inner side of the outer ring, and the outer side of the outer ring is connected to the inner wall of the filter tube.

[0035] The middle ring is a flexible ring made of a flexible material, and the center hole is the inner hole of the inner ring.

[0036] The present solution provides a specific implementation method of the first baffle, in which the inner ring and the outer ring are used as the connection structure between the intermediate ring and the central tube, and the intermediate ring and the filter tube respectively, the outer side of the inner ring is sealed to the inner side of the intermediate ring, the outer side of the intermediate ring is sealed to the inner side of the outer ring, and the outer side of the outer ring is sealed to the inner wall of the filter tube, and the sealed connection includes but is not limited to the use of crimping, welding, bonding and the like. For example, the outer side of the inner ring and the inner side of the outer ring are both provided with annular grooves, the inner side of the intermediate ring is embedded in the groove of the inner ring, and the outer side of the intermediate ring is embedded in the groove of the outer ring, and each groove is provided with a pressing plate, and the inner ring is provided with a pressure plate. The inner ring and the outer ring are both equipped with clamping screws. For example, for the inner and outer edges of the middle ring, each edge is respectively stretched and folded, embedded in the corresponding groove and supported on the lower side of the groove, and then the split pressure plate is stacked on the upper end surface of each edge, and then the clamping screws are tightened to provide a clamping force for the pressure plate, thereby completing the sealing connection between the inner ring, the middle ring and the outer ring. As an anti-slip measure, a plurality of smooth protrusions are arranged on the lower end surface of the pressure plate, and these protrusions are used to have a deeper sinking depth on the middle ring to avoid failure of the connection between the inner ring, the middle ring and the outer ring. The purpose of setting up this scheme is: especially for the liquid level detection device located in the second water accumulation chamber, which is easy to be damaged or its performance is excessively degraded during the long-term use of well logging. When it is necessary to maintain the liquid level detection device and the well pump, when the filter tube located in the well logging produces radial deformation under the compression of the formation, when the first partition plate with an intermediate ring is used, due to the connection relationship between the central tube and the filter tube through the intermediate ring, the central tube is flexibly constrained in the filter tube, and the above radial deformation is not easy to cause the first partition plate and the central tube to be stuck to each other. After the filter tube produces radial deformation, the central tube can still be pulled out from the filter tube and inserted into the filter tube. The structure inside the central tube can be pulled out with the central tube to the ground for maintenance, and the central tube can be reinstalled after maintenance is completed, thereby improving the maintainability of this detection system.

[0037] In a specific embodiment, the middle ring is a rubber ring made of rubber, the inner ring is a plastic ring made of polytetrafluoroethylene, and a chamfer is provided on the inner side of the upper end of the inner ring, and the chamfer forms a tapered hole at the upper end of the center hole;

[0038] It also includes an O-ring arranged in the center hole and below the chamfer, an annular groove is arranged on the wall of the center hole, the O-ring is embedded in the annular groove and is bonded to the groove surface of the annular groove, the O-ring is coaxial with the center hole, and the inner side of the O-ring protrudes relative to the wall of the center hole.

[0039] The above scheme provides a specific implementation form of the intermediate ring. In specific implementation, the flexible material can be flexible materials such as waterproof cloth, but such materials do not have elasticity, and it is easy for the end of the central tube to deviate from the central hole during the insertion process of the central tube. When a rubber ring is used, the shape retention ability of the rubber ring can keep the inner ring coaxial with the central tube under the tension from all sides of the intermediate ring, thereby facilitating the insertion of the central tube into the filter tube that has not undergone radial deformation. For the filter tube that has undergone radial deformation, when the deformation position is located near the position of the first partition plate, the position of the central hole may also change to a certain extent. By configuring to also include chamfering, and the chamfering forms a tapered hole located at the upper end of the central hole, during the insertion When inserting the center tube, the tapered hole forms a guide hole at the upper end of the inner ring. After the center tube is embedded in the tapered hole, the center tube can be more efficiently introduced into the center hole with the help of the tapered hole. The material properties of the inner ring polytetrafluoroethylene are used to reduce the friction between the inner ring and the end of the center tube. The density of polytetrafluoroethylene is greater than that of water, which can make the inner ring on the first baffle have a certain falling posture, so that the first baffle has a tapered cavity with a larger top and a smaller bottom, which facilitates the coordination of the center tube and the center hole when the center tube is inserted. The O-ring is used to separate the first water accumulation cavity from the first isolation cavity (some leakage is allowed here). The O-ring is embedded in the annular groove and bonded to the annular groove to prevent the O-ring from falling off the first baffle during the assembly of the center tube.

[0040] In a specific embodiment, when the middle ring is made of flexible materials such as waterproof cloth, the inner ring is preferably a metal ring, and the larger deadweight of the inner ring is used to constrain the position of the center hole in the radial direction of the filter tube to facilitate the insertion of the center tube into the center hole.

[0041] As a specific application of the above detection system, in a specific embodiment, it involves a groundwater pollution detection method, which collects detection samples from the well logging and detects the groundwater pollution in the well logging based on the detection samples. The method is implemented based on the above detection system. In this detection method, the method of collecting the detection samples is:

[0042] The machine well pump starts at the set time or according to the control command, and pumps the groundwater in the well from the central pipe into the water storage device;

[0043] Wherein, before the water storage device collects the water from the pumped well, if there is water remaining in the second water storage device, the residual water in the second water storage device is discharged through the discharge pipeline connected to the second water storage device, and the discharge pipeline is cut off after the discharge is completed;

[0044] When the water storage device collects water from the pumped well pump, the water pumped by the pumped well pump passes through the first one-way valve, the first water storage device, and the second one-way valve in sequence and enters the second water storage device. When the liquid level detection device detects that the liquid level in the second water storage device reaches or exceeds the set liquid level, the pumped well pump stops pumping water.

[0045] After the pump stops pumping water, the inlet and outlet sides of the first water storage device are cut off by the first one-way valve and the second one-way valve, and the water retained in the first water storage device is used as a test sample;

[0046] When the first water storage device is detachably connected to the water outlet pipe, after the flexible joint is removed, a test sample is collected from the first water storage device;

[0047] When the first water storage device is provided with a discharge pipeline, the test sample is collected from the first water storage device through the discharge pipeline, and the pressure equalization hole is opened during the collection process;

[0048] The set liquid level is: when the water in the second water storage device reaches the set liquid level, the volume of the water in the second water storage device is greater than or equal to the sum of the volume of the water that can be retained by the outlet pipe and the volume of the water that can be retained by the first water storage device;

[0049] After the test sample is collected, contamination detection of the test sample is completed in the laboratory.

[0050] In a specific embodiment, the detection system used in the method is a detection system in which a sensor module is arranged in the second water accumulation chamber, so that when quantitative pollution detection of groundwater pollution is required, the first water storage device automatically stores water. In the method, the sensor module automatically detects according to a set detection frequency and transmits the detection result to the control module in real time. When the control module determines that the detection item result detected by the sensor module exceeds the set item result threshold, the control module controls the machine well pump to start, so as to pump water into the water storage device through the water outlet pipe;

[0051] When the control module determines that the liquid level in the second water storage device reaches or exceeds the set liquid level according to the detection result of the liquid level detection device, the control module controls the pump to stop pumping water;

[0052] When the control module determines that the test item result detected by the sensor module exceeds the set item result threshold, the control module uploads the test sample collection instruction to the control center.

[0053] In this scheme, the project result threshold is used to determine whether the groundwater quality deviates from the set range. When the test project result exceeds the set project result threshold, it is determined that the pollution exceeds the standard. At this time, the machine well pump and other devices work, and based on the signal feedback from the liquid level detection device, the groundwater pump serving as the test sample is pumped to the first water storage device, and a test sample collection signal is sent to the control center through the uploaded test sample collection instruction.

[0054] The present invention has the following beneficial effects:

[0055] This solution can make the water retained in the first water storage device the water extracted from the central pipe. When this part of water is used for pollution project detection, the detection results can accurately reflect the current groundwater pollution situation. From the perspective of the reliability of the source of groundwater sampling detection samples and the possible introduction of water quality interference factors in the groundwater pumping process, this solution is beneficial to the sampling quality of detection samples.

[0056] From the perspective of protecting test samples and ensuring sampling efficiency, this solution is suitable for water bodies pumped by machine-well pumps with small flow rates. This method of pumping inspection samples can avoid disturbances to well logging during groundwater pumping and affect the quality of groundwater sampling, and has the characteristic of ensuring the sampling efficiency of sampling personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 This is a schematic diagram of the structure of a specific embodiment of the groundwater pollution detection system described in this solution;

[0058] Figure 2 A cross-sectional view of a specific embodiment of the first water storage device described in this solution;

[0059] Figure 3 A top view of a specific embodiment of the first water storage device described in this solution;

[0060] Figure 4 for Figure 1 The structural diagram of the part circled by the box A in the middle;

[0061] Figure 5 A cross-sectional view for illustrating the structure of a specific first baffle embodiment in the present solution;

[0062] Figure 6 A cross-sectional view for illustrating a specific structure of a first baffle embodiment in the present solution, which is a partial schematic view of the position of the inner ring of the first baffle;

[0063] Figure 7 This is a front view of a specific embodiment of the filter tube described in this scheme;

[0064] Figure 8This is a front view of a specific embodiment of the liquid level detection device described in this scheme.

[0065] The reference numerals in the figure are respectively: 1. filter tube, 11. first water accumulation chamber, 12. first isolation chamber, 13. first partition, 131. outer ring, 132. middle ring, 133. inner ring, 134. center hole, 135. chamfer, 136. O-ring, 2. center tube, 21. second water accumulation chamber, 22. second isolation chamber, 23. second partition, 3. machine well pump, 4. sensor module, 5. outlet pipe, 6. water intake module, 61. first one-way valve, 62. first shut-off valve, 63. first water storage device, 631. water distribution assembly, 64. second shut-off valve, 65. flexible joint, 66. second one-way valve, 67. second water storage device, 68. liquid level detection device, 681. liquid level tube, 682. float, 683. magnetic detector, 684. holder, 69. discharge pipeline. DETAILED DESCRIPTION

[0066] The present invention will be further described in detail below in conjunction with the embodiments, but the present invention is not limited to the following embodiments.

[0067] Embodiment 1:

[0068] like Figure 1 to Figure 8 As shown, a groundwater pollution detection system includes a filter tube 1 and a central tube 2 coaxially arranged in the filter tube 1, and also includes a machine well pump 3 arranged in the central tube 2, a water outlet pipe 5 connected to the machine well pump 3, and a water storage device connected to the outlet side of the water outlet pipe 5. The filter tube 1 and the central tube 2 are both pipes with filter holes arranged on the pipe wall. The water storage device includes a first water storage device 63 and a second water storage device 67. The first water storage device 63 is connected in series to the water outlet pipe 5, and the second water storage device 67 is connected to the end of the water outlet pipe 5. The first water storage device 63 is a component of the pipeline between the machine well pump 3 and the second water storage device 67.

[0069] The second water storage device 67 is provided with a liquid level detection device 68 for detecting the liquid level in the second water storage device 67, a first one-way valve 61 is provided on the water outlet pipe 5 on the inlet side of the first water storage device 63, and a second one-way valve 66 is provided on the water outlet pipe 5 on the outlet side of the first water storage device 63. The conduction direction of the first one-way valve 61 is to allow the water outlet pipe 5 to inject water into the first water storage device 63, and the conduction direction of the second one-way valve 66 is to allow the water outlet pipe 5 to inject water into the second water storage device 67;

[0070] The first water storage device 63 is detachably connected to the water outlet pipe 5 or the first water storage device 63 is provided with an openable and closable discharge pipeline;

[0071] When the first water storage device 63 is detachably connected to the water outlet pipe 5, both ends of the first water storage device 63 are connected in series to the water outlet pipe 5 through the flexible joint 65;

[0072] When the first water storage device 63 is provided with a discharge pipeline, the upper end of the first water storage device 63 is provided with an openable and closable pressure equalizing hole.

[0073] The above scheme is applied to groundwater pollution detection during its implementation. Specifically, it can be used to collect test samples for groundwater pollution detection from logging wells, so as to obtain more pollution detection project test results and more accurate test results on the ground or in the testing laboratory.

[0074] When the detection system is in use, the filter tube 1 and the central tube 2 are both placed in the well logging (detection well), the pump 3 is installed in the central tube 2, and the water storage device is arranged above the ground, so that the groundwater of the well logging enters the filter tube 1 through the filter holes on the filter tube 1, and the groundwater in the filter tube 1 enters the central tube 2 through the filter holes on the central tube 2, which enables the pump 3 located in the central tube 2 to pump groundwater to the water storage device through the outlet pipe 5. The filter tube 1 is not only used as a support pipe for the well logging to maintain the structural stability of the well logging, but also forms a protective cover located outside the pump 3 together with the central tube 2 when the pump 3 is working, isolating the disturbance caused to the well logging wall by the sudden shaking of the pump 3 when the pump 3 is started, and expanding the water inlet area of ​​the central tube 2 and the side wall of the filter tube 1 after the pump 3 is started through the filter holes on the central tube 2 and the filter tube 1, so as to avoid the pump 3 from taking water at a concentrated position in the well logging.

[0075] Compared with the existing common water pollution well logging detection system, the structural features of this solution include the structural design of the water storage device to obtain a differentiated detection sample collection method. When in use, the machine well pump 3 is started at a set time or according to a control instruction to pump the groundwater in the well logging from the central pipe 2 into the water storage device. Before the water storage device collects the water from the machine well pump 3, if there is residual water in the second water storage device 67, the residual water in the second water storage device 67 is discharged in advance through the discharge pipeline 69 connected to the second water storage device 67. After the discharge is completed, the discharge pipeline 69 is cut off so that the water from the end of the outlet pipe 5 can be completely collected by the second water storage device 67. When the water storage device collects the water from the machine well pump 3, the water pumped by the machine well pump 3 passes through the first one-way valve 61, the first water storage device 63, and the second one-way valve 66 in sequence and enters the second water storage device 67. When the liquid level detection device passes through When the device 68 detects that the liquid level in the second water storage device 67 reaches or exceeds the set liquid level, the machine well pump 3 stops pumping water; after the machine well pump 3 stops pumping water, the inlet side and the outlet side of the first water storage device 63 are cut off by the first one-way valve 61 and the second one-way valve 66, and the water retained in the first water storage device 63 is used as a test sample. When the first water storage device 63 is detachably connected to the water outlet pipe 5, after removing the live joint 65, the test sample is collected from the first water storage device 63. The test sample collection method can be to discharge the water in the first water storage device 63 on site, and collect these waters as test samples for subsequent water pollution project detection, or after blocking both ends of the first water storage device 63, carry the first water storage device 63 to the laboratory, and then discharge the water in the first water storage device 63, and collect these waters as test samples for use in subsequent detection projects;When the first water storage device 63 is provided with a discharge pipeline, the test sample is collected from the first water storage device 63 through the discharge pipeline, and the pressure equalizing hole is opened during the collection process. The pressure equalizing hole can not only improve the efficiency of the discharge pipeline in discharging the test sample, but also, because the first water storage device 63 can complete the pressure equalization independently of the discharge pipeline in the discharge process, compared with the discharge pipeline inhaling air process, a large number of bubbles will be formed in the collected sample. The pressure equalizing hole only allows the liquid surface position in the first water storage device 63 to have the opportunity for the collected sample to contact with the air. Therefore, the above pressure equalizing hole is beneficial to reducing the opportunity for the test sample to contact with the air during the sampling process. The set liquid level is: when the water body in the second water storage device 67 reaches the set liquid level, the volume of the water body in the second water storage device 67 is large is equal to or greater than the sum of the volume of water that can be retained in the outlet pipe 5 and the volume of water that can be retained in the first water storage device 63. Thus, when the water in the second water storage device 67 reaches the set liquid level, it means that the water that may be retained in the outlet pipe 5 and the water retained in the first water storage device 63 before the pump 3 is started are squeezed into the second water storage device 67. At this time, after the pump 3 is stopped, under the action of the two shut-off valves, the water retained in the first water storage device 63 at this time can be the water extracted from the central pipe 2. When this part of water is used for pollution project detection, the detection result can accurately reflect the current groundwater pollution situation. After the detection sample is collected through the first water storage device 63, the detection sample pollution detection is completed in the laboratory. ;

[0076] As introduced in the above method of using the water storage device, the second water storage device 67 and the liquid level detection device 68 are used to calibrate that the water in the first water storage device 63 when the machine-well pump 3 is stopped is no longer the water previously retained in the outlet pipe 5 and the first water storage device 63, or that the water in the first water storage device 63 when the machine-well pump 3 is stopped is the water retained in the first water storage device 63 after pre-flushing the outlet pipe 5 and the first water storage device 63 under the action of the pumping water of the machine-well pump 3. Therefore, from the perspective of the reliability of the source of groundwater sampling detection samples and the possible introduction of water quality interference factors in the groundwater pumping process, this scheme is beneficial to the sampling quality of the detection samples.

[0077] On the other hand, when the machine well pump 3 stops operating, the first one-way valve 61 and the second one-way valve 66 cut off the front and rear ends of the first water storage device 63. At this time, the water retained in the first water storage device 63 is enclosed in a closed space. This not only prevents this part of the water from flowing back, but also prevents this part of the water from being polluted by external factors while waiting for sampling. On the other hand, the structural characteristics of the water storage device provide the water in the first water storage device 63 with an anti-external pollution protection function. In this way, the first water storage device 63 can store test samples before the arrival of the sample collection personnel. It only needs to ensure that there are sufficient inspection samples in the first water storage device 63 after the arrival of the collection personnel. Therefore, from the perspective of protecting the test samples and ensuring the sampling efficiency, this scheme is suitable for small-flow pumping water bodies by the machine well pump 3. This inspection sample pumping method can avoid disturbances to well logging during the pumping of groundwater and affect the quality of groundwater sampling, and has the characteristic of ensuring the sampling efficiency of the sampling personnel.

[0078] More specifically, the number of the first water storage devices 63 is greater than or equal to 2. Each time an inspection sample is obtained from the system, the water retained in the second water storage device 67 is drained, and the first water storage device 63 on the lower water storage device is removed and taken back to the laboratory. In a laboratory environment, the test sample is obtained from the first water storage device 63 and the water pollution test is completed. That is, the first water storage device 63 is used as a test sample transfer container to reduce the number of transfers in the process of obtaining the test sample, reduce the interference to the water quality of the test sample during the transfer process, and improve the convenience of sampling the test sample. A new first water storage device 63 is installed on the water storage device to prepare for the next time the test sample is obtained.

[0079] In more detail, the first water storage device 63 is detachably connected to the water outlet pipe 5, and at the end of the water outlet pipe 5, a first one-way valve 61, a flexible joint 65, a first shut-off valve 62, a first water storage device 63, a second shut-off valve 64, a flexible joint 65 and a second one-way valve 66 are sequentially connected in series on the water outlet pipe 5;

[0080] The first water storage device 63 is a tubular container with nozzles at both ends. The first water storage device 63 is connected to the first shut-off valve 62 and the second shut-off valve 64 through the nozzles at the ends.

[0081] In this solution, the first shutoff valve 62, the first water storage device 63, and the second shutoff valve 64 form a water intake module 6, that is, by operating the flexible joints 65 at both ends of the water intake module 6, the water intake module 6 can be detached from the water storage device. Based on such a structure, the detection sample sampling process can be: when the machine well pump 3 is started and it is determined by the liquid level detection device 68 that the first water storage device 63 has completed water storage, the machine well pump 3 is turned off. After the sampling personnel arrive at the scene, they close the first shutoff valve 62 and the second shutoff valve 64, disassemble the flexible joints 65 at both ends of the water intake module 6, and separate the storage device 6 from this system. A water intake module 6 storing a test sample is provided, and a new water intake module 6 is connected in series to the water outlet pipe 5 through the flexible joint 65, and the first shut-off valve 62 and the second shut-off valve 64 are checked to make sure that both the first shut-off valve 62 and the second shut-off valve 64 are in an open state. The removed water intake module 6 is then brought back to the laboratory. When the test sample is needed, the water intake module 6 is erected and the first shut-off valve 62 and the second shut-off valve 64 are opened. The upper end of the water intake module 6 is used as the air inlet end and the lower end as the water outlet end, so as to discharge the test sample from the first water storage device 63 in a manner that reduces the chance of contact between the water body and the air. The first water storage device 63 which is a tubular container is adopted for the purpose that: such a structural form of the first water storage device 63 enables the water in the first water storage device 63 to be pushed forward as much as possible by the water entering from the rear and discharged from the front of the first water storage device 63 during the water intake and water discharge process of the first water storage device 63. In this way, after the machine well pump 3 stops operating, the water originally retained in the detection system and the water used as flushing water in the early stage of starting the machine well pump 3 can be discharged from the first water storage device 63 as much as possible, thereby ensuring the quality of the sample retention for detection by this detection system.

[0082] In more detail, the first water storage device 63 is a strip-shaped flat tube with an enlarged middle part. The pipe openings at both ends of the first water storage device 63 are located in the center of the width direction of the first water storage device 63. The pipe openings of the first water storage device 63 are connected to the enlarged structure in the middle of the first water storage device 63 through a reducing section. A water distribution assembly 631 is provided in the pipe opening of the first water storage device 63 connected to the first shut-off valve 62. The water distribution assembly 631 is used to evenly distribute the water from the first water storage device 63 on the pipe cross-section of the first water storage device 63.

[0083] In this solution, the first water storage device 63 is a flat tube structure with an expanded middle portion, which is used to ensure the volume of the first water storage device 63, and to make the end of the first water storage device 63 have a smaller pipe opening to facilitate its series connection on the water outlet pipe 5. When in use, the installation posture of the first water storage device 63 is a flat posture. The structural features of the first water storage device 63 are: having a variable diameter section at both ends, an expanded structure in the middle, and a pipe opening located in the center of the width direction, which is used to make the first water storage device 63 perpendicular to the water flow direction ( Figure 2On the pipe cross section (in the direction indicated by the arrow in the middle), the flow velocity at each position of the cross section is relatively uniform, so as to avoid the water in the first water storage device 63 not being fully replaced during the water flow process due to the existence of a flow dead angle in the first water storage device 63. The water distribution component 631 is used to further constrain the flow field state in the first water storage device 63 when the water is passed, so that the water entering the first water storage device 63 when the water is taken in can be evenly distributed on the pipe cross section, so that the water at each position in the first water storage device 63 has a forward-flowing state. Therefore, the water distribution component 631 is a water distribution structure arranged based on the configuration of the first water storage device 63, which is used to forcibly constrain the water flow state in the first water storage device 63.

[0084] In more detail, the water distribution assembly 631 is a block structure on which a plurality of water distribution holes are arranged, and the block structure is embedded in the pipe hole on the inlet side of the first water storage device 63, and the opening of one end of the water distribution hole faces the outside of the first water storage device 63, and the opening of the other end faces the inside of the first water storage device 63. The openings of these water distribution holes facing the inside of the first water storage device 63 have multiple directions, so that the water entering the first water storage device 63 through different water distribution holes has different flow directions, so as to achieve the purpose of uniform flow rate and flow velocity at various positions on the pipe cross section of the first water storage device 63.

[0085] In more detail, the liquid level detection device 68 includes a liquid level tube 681 connected to the second water storage device 67, a float 682 arranged in the liquid level tube 681, a holder 684 clamped on the liquid level tube 681, and a magnetic detector 683 installed on the holder 684, wherein a magnet is arranged in the float 682, and the position of the holder 684 in the height direction of the liquid level tube 681 is adjustable.

[0086] This solution is used to solve the problem of the front-end drainage volume under different water intake depths of the machine-well pump 3, and is used to ensure the sampling quality of the test samples in the first water storage device 63. Specifically, for different setting depths of the machine-well pump 3, it is necessary to configure the outlet pipe 5 to have a length that adapts to the depth. When the same size of the outlet pipe 5 and the size of the first water storage device 63 are used, before the machine-well pump 3 is stopped, the amount of front flushing water discharged and the amount of retained water discharged from the outlet pipe 5 are related to the length of the outlet pipe 5. When the machine-well pump 3 is deeper, the water discharge is The pipe 5 is longer, and more water needs to be discharged into the second water storage device 67 before the first water storage device 63 stores the test sample. When the pump 3 is shallow, the water outlet pipe 5 is shorter, and less water needs to be discharged into the second water storage device 67 before the first water storage device 63 stores the test sample. With the above solution, the position of the magnetic induction zone of the liquid level detection device 68 is adjusted by adjusting the position of the holder 684 on the liquid level pipe 681. When the holder 684 is at a higher position, only when the float 682 carries the magnet with the second water storage device 6 7 is detected by the magnetic detector 683 only when the liquid level of the second water storage device 67 rises to a higher position. At this time, there is more water in the second water storage device 67, which means that more water is discharged from the end of the water outlet pipe 5. On the contrary, when the position of the holder 684 on the liquid level tube 681 is lower, the float 682 carries the magnet and rises to a lower position with the liquid level of the second water storage device 67. It is detected by the magnetic detector 683. At this time, there is less water in the second water storage device 67, which means that less water is discharged from the end of the water outlet pipe 5. This scheme is essentially a float level gauge. Compared with other methods such as detecting the water flow at the end of the outlet pipe 5 by flow meter, detecting the liquid level of the second water storage device 67 by capacitance value, pressure, ultrasonic wave, radar wave, etc., it not only has low implementation and maintenance costs, and the detection results are not easily disturbed, but also can adjust the drainage volume in a targeted manner for specific application occasions. The matching adjustment can be completed by moving the holder 684 on the liquid level pipe 681, and the magnetic detector 683 plays the role of a switch in place, so this scheme also has the characteristic of simple debugging. In specific applications, the maximum retained water volume of the outlet pipe 5 and these pipes can be calculated according to the length of the outlet pipe 5 currently used and the size of the first water storage device 63 and other pipes, and then the minimum height of the holder 684 on the liquid level pipe 681 can be calculated according to the volume, and then the holder 684 can be adjusted so that the actual height of the holder 684 is equal to or higher than the minimum height, so that the outlet pipe 5 of the first water storage device 63 can be guaranteed to have the minimum drainage volume before the test sample is stored to ensure the quality of the water in the first water storage device 63.The working principle of the liquid level detection device 68 is as follows: when the float 682 carries the magnet and moves toward the magnetic detector 683 on the holder 684, the magnetic flux detected by the magnetic detector 683 serving as a fluxmeter changes. When the magnetic flux detection result reaches the set threshold, it means that the float 682 has risen to a higher position along with the liquid level of the second water storage device 67. That is, this scheme uses the method that the position of the magnet changes with the height of the liquid level in the second water storage device 67, and the magnetic detector 683 obtains different detection results according to the position of the magnet to determine whether the liquid level in the second water storage device 67 has reached the required height.

[0087] More specifically, the filter tube 1 and the central tube 2 are both provided with a baffle group, the baffle group on the filter tube 1 includes two first baffles 13 arranged at different positions of the filter tube 1, each first baffle 13 is provided with a central hole 134, and the central tube 2 passes through each first baffle 13 through the central hole 134;

[0088] The partition group on the filter tube 1 divides the filter tube 1 into a first water accumulation chamber 11 and a first isolation chamber 12 arranged along the axis of the filter tube 1, wherein the first isolation chamber 12 is a chamber surrounded by two first partitions 13 of the partition group on the filter tube 1, and the first water accumulation chamber 11 is a chamber outside the partition group on the filter tube 1, and the filter holes on the filter tube 1 are located on the side wall of the first water accumulation chamber 11;

[0089] The baffle group on the central tube 2 includes two second baffles 23 arranged at different positions of the central tube 2. The baffle group on the central tube 2 divides the central tube 2 into a second water accumulation chamber 21 and a second isolation chamber 22 arranged along the axis of the central tube 2, wherein the second isolation chamber 22 is a chamber surrounded by two second baffles 23 of the baffle group on the central tube 2, the second water accumulation chamber 21 is a chamber outside the baffle group on the central tube 2, and the filter hole on the central tube 2 is located on the side wall of the second water accumulation chamber 21;

[0090] The second isolation chamber 22 spans the first isolation chamber 12. Both the first isolation chamber 12 and the second isolation chamber 22 are sealed chambers. Each first water accumulation chamber 11 has a second water accumulation chamber 21 that is connected to the first water accumulation chamber 11 through a filter hole on the central tube 2. Each second water accumulation chamber 21 is provided with a machine well pump 3, and each machine well pump 3 is equipped with a water outlet pipe 5 and a water storage device.

[0091] In this solution, two first partitions 13 included in the partition group on the filter tube 1 are used to divide the space inside the filter tube 1 into first water accumulation chambers 11 arranged along the axial direction, that is, a first isolation chamber 12 of a certain length is provided between two adjacent first water accumulation chambers 11. When used for groundwater sampling at different depths, the mutual interference of groundwater at different depths can be reduced. From the perspective of groundwater sampling depth, the groundwater collected from each first water accumulation chamber 11 is more representative. In the present solution, the two second partitions 23 included in the partition group on the central tube 2 are used to divide the central tube 2 into second water accumulation chambers 21 arranged along the axial direction, and the second partition chamber is used to make the second water accumulation chamber 21 and the first water accumulation chamber 11 fit in position, so as to establish a one-to-one conductive relationship between the second water accumulation chamber 21 and the first water accumulation chamber 11. At the same time, the water storage capacity of the central tube 2 is reduced by the second isolation chamber 22. When it is necessary to lift the central tube 2 to maintain the well pump 3 and the sensor module 4 installed thereon, since the second isolation chamber 22 is a cavity in the central tube 2, such a cavity layout can reduce the force required to lift the central tube 2, thereby achieving the purpose of improving the convenience of repair of the system.

[0092] In more detail, for two or more second water accumulation chambers 21 distributed up and down, the water outlet pipe 5 configured for the machine well pump 3 in the lower second water accumulation chamber 21 passes through the second partition 23 above, extends to the side inlet through the inner space of the central pipe 2 and is connected to the water storage device, and the machine well pumps 3 at different heights are connected in series through steel wire ropes, and the positions where the steel wire ropes and the water outlet pipe 5 cooperate with the second partition 23 are all sealed and connected, so that the second water accumulation chambers 21 at different heights in the central pipe 2 can be completely isolated from each other. The sealed connection can be: for the wire rope and the water outlet pipe 5, after each of them passes through the second partition 23, the gap between each of them and the second partition 23 is sealed with flexible glue to avoid sealing failure at these positions due to vibration during the operation of the system.

[0093] In more detail, each second water accumulation chamber 21 is provided with a sensor module 4 for detecting groundwater pollution;

[0094] Each second water accumulation chamber 21 is provided with an operation window located on the side wall of the central tube 2 . The operation window is covered by a cover plate, and the cover plate is detachably connected to the side wall of the central tube 2 .

[0095] In this solution, the sensor module 4 is used to detect the water quality of groundwater in the second water accumulation chamber 21 online. The specific method of use is: use the detection result of the sensor module 4 to provide a qualitative reference for the groundwater pollution situation. When the detection result is contaminated and further quantitative detection of pollution is required, use the water storage device to obtain laboratory test samples to complete the detection of more items and obtain more accurate test results. After opening, the operation window serves as an operation window for installing and maintaining the well pump 3 and the liquid level detection device 68, and as an operation window for completing the connection between the outlet pipe 5 and the outlet of the well pump 3 and using flexible glue to seal the gap. After completing the relevant operations through the second water accumulation chamber 21, the operation window is covered by the cover plate, and then the central tube 2 can be placed in the filter tube 1. In the specific implementation, in order to increase the water inlet area of ​​the second water accumulation chamber 21, the cover plate and the side wall of the second water accumulation chamber 21 outside the cover plate are provided with filter holes.

[0096] In more detail, the first baffle 13 includes an outer ring 131, an intermediate ring 132 and an inner ring 133, all of which are annular structures. The outer ring 131, the intermediate ring 132 and the inner ring 133 are all coaxial with the filter tube 1. The outer side of the inner ring 133 is connected to the inner side of the intermediate ring 132, the outer side of the intermediate ring 132 is connected to the inner side of the outer ring 131, and the outer side of the outer ring 131 is connected to the inner wall of the filter tube 1.

[0097] The middle ring 132 is a flexible ring made of a flexible material, and the center hole 134 is the inner hole of the inner ring 133 .

[0098] The present solution provides a specific implementation of the first baffle 13. In the structure, the inner ring 133 and the outer ring 131 are respectively used as the connection structure between the intermediate ring 132 and the central tube 2, and the intermediate ring 132 and the filter tube 1. The outer side of the inner ring 133 is sealed to the inner side of the intermediate ring 132, the outer side of the intermediate ring 132 is sealed to the inner side of the outer ring 131, and the outer side of the outer ring 131 is sealed to the inner wall of the filter tube 1. The sealed connection includes but is not limited to the use of crimping, welding, bonding and the like. For example, the outer side of the inner ring 133 and the inner side of the outer ring 131 are both provided with an annular groove, the inner side of the intermediate ring 132 is embedded in the groove of the inner ring 133, and the outer side of the intermediate ring 132 is embedded in the groove of the outer ring 131. The grooves are all equipped with pressure plates, and the inner ring 133 and the outer ring 131 are all equipped with clamping screws. For example, for the inner and outer edges of the middle ring 132, each edge is respectively stretched and folded, embedded in the corresponding groove and supported on the lower side of the groove, and then the split pressure plates are stacked on the upper end faces of each edge, and then the clamping screws are tightened to provide clamping force for the pressure plates, thereby completing the sealing connection between the inner ring 133, the middle ring 132, and the outer ring 131. As an anti-slip measure, a plurality of smooth protrusions are arranged on the lower end face of the pressure plate, and these protrusions are used to have a deeper sinking depth on the middle ring 132 to avoid failure of the connection between the inner ring 133, the middle ring 132, and the outer ring 131. The purpose of setting up this scheme is: especially for the liquid level detection device 68 located in the second water accumulation chamber 21, which is easy to be damaged or its performance is excessively degraded during the long-term use of well logging. When it is necessary to maintain the liquid level detection device 68 and the well pump 3, when the filter pipe 1 located in the well logging produces radial deformation under the compression of the formation, when the first partition plate 13 with the intermediate ring 132 is used, due to the connection relationship between the central pipe 2 and the filter pipe 1 through the intermediate ring 132, the central pipe 2 is flexibly constrained in the filter pipe 1, and the above radial deformation is not easy to cause the first partition plate 13 and the central pipe 2 to be stuck to each other. After the filter pipe 1 produces radial deformation, the central pipe 2 can still be pulled out from the filter pipe 1 and inserted into the filter pipe 1. The structure inside the central pipe 2 can be pulled out with the central pipe 2 to the ground for maintenance, and the central pipe 2 can be reinstalled after maintenance is completed, thereby improving the maintainability of this detection system.

[0099] More specifically, in order to monitor whether the filter tube 1 at the position of the first partition 13 is deformed, a plurality of tension sensors arranged around the middle ring 132 may be configured for the middle ring 132. The tension sensors are used to measure the tension of the middle ring 132 at their positions. In this way, based on the measurement values ​​of the tension sensors at different positions, it can be determined whether the filter tube 1 is squeezed and deformed at the position of the first partition 13. Therefore, the measurement values ​​can be used to complete the well logging life determination and provide a reference for well logging and well repair.

[0100] In more detail, the middle ring 132 is a rubber ring made of rubber, the inner ring 133 is a plastic ring made of polytetrafluoroethylene, and a chamfer 135 is provided on the inner side of the upper end of the inner ring 133, and the chamfer 135 forms a tapered hole at the upper end of the center hole 134;

[0101] It also includes an O-ring 136 arranged in the center hole 134 and located below the chamfer 135. The center hole 134 has an annular groove on its wall. The O-ring 136 is embedded in the annular groove and bonded to the groove surface of the annular groove. The O-ring 136 is coaxial with the center hole 134, and the inner side of the O-ring 136 protrudes relative to the wall of the center hole 134.

[0102] The above scheme provides a specific implementation form of the intermediate ring 132. During the specific implementation, the flexible material can be a flexible material such as waterproof cloth, but such a material does not have elasticity, and it is easy for the end of the central tube 2 to deviate from the central hole 134 during the insertion process of the central tube 2. When a rubber ring is used, the shape retention ability of the rubber ring can keep the inner ring 133 coaxial with the central tube 2 under the tension from all sides of the intermediate ring 132, thereby facilitating the insertion of the central tube 2 into the filter tube 1 that has not undergone radial deformation. For the filter tube 1 that has undergone radial deformation, when the deformation position is located near the position of the first partition plate 13, the position of the central hole 134 may also change to a certain extent. By setting it to also include a chamfer 135, and the chamfer 135 forms a tapered hole located at the upper end of the central hole 134, when the central tube 2 is inserted, The tapered hole forms a guide hole at the upper end of the inner ring 133. After the center tube 2 is embedded in the tapered hole, the center tube 2 can be more efficiently introduced into the center hole 134 with the help of the tapered hole. The material property of polytetrafluoroethylene of the inner ring 133 is used to reduce the friction between the inner ring 133 and the end of the center tube 2. The density of polytetrafluoroethylene is greater than that of water, which can make the inner ring 133 on the first baffle 13 have a certain falling posture, so that the first baffle 13 has a tapered cavity with a larger upper part and a smaller lower part, which facilitates the cooperation between the center tube 2 and the center hole 134 when the center tube 2 is inserted. The O-ring 136 is used to separate the first water accumulation cavity 11 from the first isolation cavity 12 (some leakage is allowed here). The O-ring 136 is embedded in the annular groove and bonded to the annular groove to prevent the O-ring 136 from falling off the first baffle 13 during the assembly of the center tube 2.

[0103] In more detail, when the middle ring 132 is made of flexible materials such as waterproof cloth, the inner ring 133 is preferably made of a metal ring, and the larger deadweight of the inner ring 133 is used to constrain the position of the center hole 134 in the radial direction of the filter tube 1 to facilitate the insertion of the center tube 2 into the center hole 134.

[0104] As a specific application of the above detection system, a more detailed method for detecting groundwater pollution is involved. After collecting detection samples from the well logging, the groundwater pollution in the well logging is detected based on the detection samples. The method is implemented based on the above detection system. In this detection method, the method for collecting the detection samples is:

[0105] The pump 3 starts at a set time or according to a control instruction, and pumps the groundwater in the well from the central pipe 2 into the water storage device;

[0106] Before the water storage device collects the water from the pump 3, if there is water remaining in the second water storage device 67, the residual water in the second water storage device 67 is discharged through the discharge pipeline 69 connected to the second water storage device 67, and the discharge pipeline 69 is cut off after the discharge is completed;

[0107] When the water storage device collects water from the pump 3, the water pumped by the pump 3 passes through the first one-way valve 61, the first water storage device 63, and the second one-way valve 66 in sequence and enters the second water storage device 67. When the liquid level detection device 68 detects that the liquid level in the second water storage device 67 reaches or exceeds the set liquid level, the pump 3 stops pumping water.

[0108] After the pump 3 stops pumping water, the inlet and outlet sides of the first water storage device 63 are cut off by the first one-way valve 61 and the second one-way valve 66, and the water retained in the first water storage device 63 is used as a test sample;

[0109] When the first water storage device 63 is detachably connected to the water outlet pipe 5, after the flexible joint 65 is removed, the test sample is collected from the first water storage device 63;

[0110] When the first water storage device 63 is provided with a discharge pipeline, the test sample is collected from the first water storage device 63 through the discharge pipeline, and the pressure equalization hole is opened during the collection process;

[0111] The set liquid level is: when the water in the second water storage device 67 reaches the set liquid level, the volume of the water in the second water storage device 67 is greater than or equal to the sum of the volume of the water that can be retained by the outlet pipe 5 and the volume of the water that can be retained by the first water storage device 63;

[0112] After the test sample is collected, contamination detection of the test sample is completed in the laboratory.

[0113] In more detail, the detection system used in the method is a detection system in which a sensor module 4 is provided in the second water accumulation chamber 21, so that when quantitative pollution detection of groundwater pollution is required, the first water storage device 63 automatically stores water. In the method, the sensor module 4 automatically detects according to the set detection frequency and transmits the detection result to the control module in real time. When the control module determines that the detection item result detected by the sensor module 4 exceeds the set item result threshold, the control module controls the machine well pump 3 to start, so as to pump water into the water storage device through the water outlet pipe 5;

[0114] When the control module determines that the liquid level in the second water storage device 67 reaches or exceeds the set liquid level according to the detection result of the liquid level detection device 68, the control module controls the pump 3 to stop pumping water;

[0115] When the control module determines that the detection item result detected by the sensor module 4 exceeds the set item result threshold, the control module uploads the detection sample collection instruction to the control center.

[0116] In this scheme, the project result threshold is used to determine whether the groundwater quality deviates from the set range. When the test project result exceeds the set project result threshold, it is determined that the pollution exceeds the standard. At this time, the machine well pump 3 and others work, and based on the signal feedback from the liquid level detection device 68, the groundwater pump as the test sample is pumped to the first water storage device 63, and a test sample collection signal is sent to the control center through the uploaded test sample collection instruction.

[0117] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific embodiments of the present invention are limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, other embodiments obtained without departing from the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. A groundwater pollution detection system, comprising a filter tube (1) and a central tube (2) coaxially arranged in the filter tube (1), and further comprising a machine well pump (3) arranged in the central tube (2), a water outlet pipe (5) connected to the machine well pump (3), and a water storage device connected to the outlet side of the water outlet pipe (5), wherein the filter tube (1) and the central tube (2) are both pipes with filter holes arranged on the pipe wall, characterized in that: The water storage device comprises a first water storage device (63) and a second water storage device (67), the first water storage device (63) being connected in series to the water outlet pipe (5), the second water storage device (67) being connected to the end of the water outlet pipe (5), and the first water storage device (63) being a component of the pipeline between the machine well pump (3) and the second water storage device (67); The second water storage device (67) is provided with a liquid level detection device (68) for detecting the liquid level in the second water storage device (67); the water outlet pipe (5) on the inlet side of the first water storage device (63) is provided with a first one-way valve (61); the water outlet pipe (5) on the outlet side of the first water storage device (63) is provided with a second one-way valve (66); the first one-way valve (61) is opened in a direction to allow the water outlet pipe (5) to inject water into the first water storage device (63); and the second one-way valve (66) is opened in a direction to allow the water outlet pipe (5) to inject water into the second water storage device (67); The first water storage device (63) is detachably connected to the water outlet pipe (5) or the first water storage device (63) is provided with an openable and closable discharge pipeline; When the first water storage device (63) is detachably connected to the water outlet pipe (5), both ends of the first water storage device (63) are connected in series to the water outlet pipe (5) via the flexible joints (65); When a discharge pipeline is arranged on the first water storage device (63), an openable and closable pressure equalizing hole is arranged on the upper end of the first water storage device (63); The liquid level detection device (68) comprises a liquid level tube (681) connected to the second water storage device (67), a floating ball (682) arranged in the liquid level tube (681), a holder (684) clamped on the liquid level tube (681), and a magnetic detector (683) mounted on the holder (684); a magnet is arranged in the floating ball (682); and the position of the holder (684) in the height direction of the liquid level tube (681) is adjustable.

2. A groundwater pollution detection system according to claim 1, characterized in that: The first water storage device (63) is detachably connected to the water outlet pipe (5); at the end of the water outlet pipe (5), a first one-way valve (61), a flexible joint (65), a first cut-off valve (62), the first water storage device (63), a second cut-off valve (64), a flexible joint (65), and a second one-way valve (66) are sequentially connected in series on the water outlet pipe (5); The first water storage device (63) is a tubular container with pipe openings at both ends, and the first water storage device (63) is connected to the first shutoff valve (62) and the second shutoff valve (64) via the pipe openings at the ends.

3. A groundwater pollution detection system according to claim 2, characterized in that: The first water storage device (63) is a strip-shaped flat tube with an expanded middle portion. The pipe openings at both ends of the first water storage device (63) are located at the center of the first water storage device (63) in the width direction. The pipe openings of the first water storage device (63) are connected to the expanded structure in the middle of the first water storage device (63) via a reducing section. A water distribution assembly (631) is provided in the pipe opening of the first water storage device (63) connected to the first shut-off valve (62). The water distribution assembly (631) is used to evenly distribute water from the first water storage device (63) on the pipe cross section of the first water storage device (63).

4. A groundwater pollution detection system according to claim 1, characterized in that: The filter tube (1) and the central tube (2) are both provided with a baffle group, the baffle group on the filter tube (1) comprising two first baffles (13) arranged at different positions of the filter tube (1), each first baffle (13) being provided with a central hole (134), and the central tube (2) passing through each first baffle (13) through the central hole (134); The partition plate group on the filter tube (1) divides the filter tube (1) into a first water accumulation chamber (11) and a first isolation chamber (12) arranged along the axis of the filter tube (1), wherein the first isolation chamber (12) is a chamber on the filter tube (1) surrounded by two first partition plates (13) of the partition plate group, the first water accumulation chamber (11) is a chamber outside the partition plate group on the filter tube (1), and the filter holes on the filter tube (1) are located on the side wall of the first water accumulation chamber (11); The baffle group on the central tube (2) comprises two second baffles (23) arranged at different positions on the central tube (2), and the baffle group on the central tube (2) divides the central tube (2) into a second water accumulation chamber (21) and a second isolation chamber (22) arranged along the axis of the central tube (2), wherein the second isolation chamber (22) is a chamber on the central tube (2) surrounded by the two second baffles (23) of the baffle group, the second water accumulation chamber (21) is a chamber outside the baffle group on the central tube (2), and the filtering hole on the central tube (2) is located on the side wall of the second water accumulation chamber (21); The second isolation chamber (22) spans the first isolation chamber (12); the first isolation chamber (12) and the second isolation chamber (22) are both sealed chambers; each first water accumulation chamber (11) has a second water accumulation chamber (21) connected to the first water accumulation chamber (11) via a filter hole on the central tube (2); each second water accumulation chamber (21) is provided with a machine well pump (3); and each machine well pump (3) is provided with a water outlet pipe (5) and a water storage device.

5. A groundwater pollution detection system according to claim 4, characterized in that: Each second water accumulation chamber (21) is provided with a sensor module (4) for detecting groundwater pollution; Each second water accumulation chamber (21) is provided with an operation window located on the side wall of the central tube (2); the operation window is covered by a cover plate, and the cover plate is detachably connected to the side wall of the central tube (2).

6. A groundwater pollution detection system according to claim 4, characterized in that: The first baffle (13) comprises an outer ring (131), an intermediate ring (132) and an inner ring (133), all of which are annular structures; the outer ring (131), the intermediate ring (132) and the inner ring (133) are all coaxial with the filter tube (1); the outer side of the inner ring (133) is connected to the inner side of the intermediate ring (132); the outer side of the intermediate ring (132) is connected to the inner side of the outer ring (131); and the outer side of the outer ring (131) is connected to the inner wall of the filter tube (1); The middle ring (132) is a flexible ring made of a flexible material, and the central hole (134) is the inner hole of the inner ring (133).

7. A groundwater pollution detection system according to claim 6, characterized in that: The middle ring (132) is a rubber ring made of rubber, the inner ring (133) is a plastic ring made of polytetrafluoroethylene, and a chamfer (135) is provided on the inner side of the upper end of the inner ring (133), and the chamfer (135) forms a tapered hole at the upper end of the center hole (134); It also includes an O-ring (136) disposed in the center hole (134) and located below the chamfer (135); an annular groove is disposed on the wall of the center hole (134); the O-ring (136) is embedded in the annular groove and is bonded to the groove surface of the annular groove; the O-ring (136) is coaxial with the center hole (134); and the inner side of the O-ring (136) protrudes relative to the wall of the center hole (134).

8. A method for detecting groundwater pollution, which collects a test sample from a well and then detects the groundwater pollution in the well based on the test sample, characterized in that: The method is implemented based on the detection system described in any one of claims 1 to 7, and the method for collecting the detection sample is: The machine well pump (3) is started at a set time or according to a control instruction, and pumps the groundwater in the well from the central pipe (2) into the water storage device; Wherein, before the water storage device collects water from the well pump (3), if there is water remaining in the second water storage device (67), the residual water in the second water storage device (67) is discharged through a discharge pipeline (69) connected to the second water storage device (67), and the discharge pipeline (69) is cut off after the discharge is completed; When the water storage device collects water from the machine-well pump (3), the water pumped by the machine-well pump (3) passes through the first one-way valve (61), the first water storage device (63), and the second one-way valve (66) in sequence and enters the second water storage device (67); when the liquid level detection device (68) detects that the liquid level in the second water storage device (67) reaches or exceeds a set liquid level, the machine-well pump (3) stops pumping water; After the well pump (3) stops pumping water, the inlet side and the outlet side of the first water storage device (63) are cut off by the first one-way valve (61) and the second one-way valve (66), and the water retained in the first water storage device (63) is used as a test sample; When the first water storage device (63) is detachably connected to the water outlet pipe (5), after the flexible joint (65) is removed, a test sample is collected from the first water storage device (63); When the first water storage device (63) is provided with a discharge pipeline, a test sample is collected from the first water storage device (63) via the discharge pipeline, and the pressure equalization hole is opened during the collection process; The set liquid level is: when the water in the second water storage device (67) reaches the set liquid level, the volume of the water in the second water storage device (67) is greater than or equal to the sum of the volume of the water that can be retained by the outlet pipe and the volume of the water that can be retained by the first water storage device (63); After the test sample is collected, contamination detection of the test sample is completed in the laboratory.

9. A method for detecting groundwater pollution according to claim 8, characterized in that: The detection system used in the method is the detection system according to claim 5. In the method, the sensor module (4) automatically detects according to a set detection frequency and transmits the detection result to the control module in real time. When the control module determines that the detection item result detected by the sensor module (4) exceeds the set item result threshold, the control module controls the machine well pump (3) to start, so as to pump water into the water storage device through the water outlet pipe (5); When the control module determines, based on the detection result of the liquid level detection device (68), that the liquid level in the second water storage device (67) reaches or exceeds the set liquid level, the control module controls the pump well pump (3) to stop pumping water; When the control module determines that the detection item result detected by the sensor module (4) exceeds a set item result threshold, the control module uploads a detection sample collection instruction to the control center.

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