A soil-aerated zone-saturated zone cross-medium groundwater automatic monitoring device and a monitoring method

Abstract

The application discloses a soil-aeration zone-saturated zone cross-medium underground water automatic monitoring device and a monitoring method. The device comprises a soil underground water automatic collection system arranged in a soil layer, an aeration zone underground water automatic collection system arranged in an aeration zone, a saturated zone underground water automatic collection system arranged in a saturated zone, an automatic cleaning system, a water quality automatic monitoring system and a control system. The device and the method can monitor the water quality of the soil layer and the aeration zone, are comprehensive, can complete soil-aeration zone-saturated zone multi-layer cross-medium underground water sampling monitoring, greatly save cost and improve efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of water quality monitoring, in particular to a soil-aerated zone-saturated zone cross-media underground water automatic monitoring device and method for various environmental monitoring. BACKGROUND

[0002] Groundwater is an important part of water resources, and its quality and quantity have a crucial impact on the ecological environment and human life. Soil, aerated zone and saturated zone are important components of the groundwater system, and they interact with each other and jointly affect the dynamic changes of groundwater. Groundwater refers to groundwater in a broad sense, i.e. water existing below the ground surface. Water existing below the ground surface includes water in the soil layer, water in the aerated zone and groundwater in the saturated zone. Groundwater in a narrow sense only refers to groundwater in the saturated zone.

[0003] In recent years, groundwater pollution has also become a problem of concern. Pollutants in the soil can enter the saturated zone through the aerated zone, thereby polluting the groundwater.

[0004] The environmental automatic monitoring method for groundwater in a narrow sense has become mature. For example, patent application 202210142180.1 discloses an intelligent monitoring device for automatic monitoring, detection and early warning of groundwater, which relates to an intelligent device for automatic, multi-dimensional and long-term monitoring of groundwater, automatic detection and threshold alarm in geological exploration and underground engineering construction. The structure includes a data storage and control module, a data transmission and connection module and a measurement unit module. For another example, patent application 202211717217.5 discloses a method for monitoring elements of groundwater circulation based on a northern full-discharge type karst spring, which includes measuring the groundwater level in the survey area, using a groundwater flow rate and direction detector to investigate the groundwater flow direction, combining geological and hydrogeological information to determine the spring area range; using a monitoring device to monitor the spring area range to obtain water quantity information; periodically sampling precipitation, karst groundwater and spring water at typical positions in the spring area range to obtain sampling information; transmitting the water quantity information and sampling information to a terminal processor for data processing to study the response relationship of groundwater level information, surface water and spring water flow information to precipitation information, and supplementing the chlorine balance method to determine the ineffective precipitation in the spring area and determine the precipitation infiltration coefficient to reveal the circulation mechanism of karst groundwater.

[0005] Therefore, monitoring the soil-aerated zone-saturated zone cross-media groundwater can more comprehensively understand the operation mechanism of the groundwater system and provide a scientific basis for the protection and management of groundwater.

[0006] However, the existing automatic groundwater monitoring equipment can only monitor the saturated water in the underground aquifer. It cannot monitor the water quality of the soil layer and the vadose zone layer. Therefore, it is urgent to improve the comprehensive and accurate monitoring of the groundwater situation to promote the good development of environmental protection. SUMMARY

[0007] Therefore, the primary object of the present application is to provide a soil-vadose zone-saturated zone cross-media automatic groundwater monitoring device and method. The device and method monitor the water quality of the soil layer and the vadose zone layer, and can complete the soil-vadose zone-saturated zone multi-layer cross-media groundwater sampling monitoring, greatly saving the cost and improving the efficiency.

[0008] Another object of the present application is to provide a soil-vadose zone-saturated zone cross-media automatic groundwater monitoring device and method. The device and method realize the full-automatic monitoring of the vertical distribution of groundwater pollutants, so that the entire groundwater monitoring work is more efficient, and the timeliness and synchronicity of data acquisition are improved, thereby improving the accuracy and reliability of water quality monitoring.

[0009] To achieve the above object, the technical solution of the present application is as follows:

[0010] A soil-vadose zone-saturated zone cross-media automatic groundwater monitoring device, the device comprises a soil groundwater automatic collection system arranged in the soil layer, a vadose zone groundwater automatic collection system arranged in the vadose zone, a saturated zone groundwater automatic collection system arranged in the saturated zone, an automatic cleaning system, a water quality automatic monitoring system and a control system; wherein the soil groundwater automatic collection system, the vadose zone groundwater automatic collection system and the saturated zone groundwater automatic collection system are located in a borehole and arranged in an up-down distribution, and the soil groundwater automatic collection system, the vadose zone groundwater automatic collection system and the saturated zone groundwater automatic collection system are respectively connected to the automatic cleaning system, the water quality automatic monitoring system and the control system; through the layered soil, vadose zone and saturated zone groundwater sampling systems arranged in a single borehole, the automatic cleaning system and the water quality automatic monitoring system and the control system are linked to realize cross-media synchronous monitoring;

[0011] The soil groundwater automatic collection system, the soil automatic collection system, collects the soil groundwater sample and transmits it to the water quality automatic monitoring system; comprising a sampling pottery head, a water content and temperature probe, and a water distribution bottle, the water content and temperature probe is connected to the control system, the sampling pottery head is connected to the water distribution bottle, and the water distribution bottle is connected to the control system and the water quality automatic monitoring system;

[0012] The automatic collection system of the groundwater in the aeration zone, the automatic collection system of the groundwater in the aeration zone, collects the groundwater sample in the aeration zone and transmits to the automatic monitoring system of water quality; comprising a sampling pottery head, a water content and temperature probe, a water distribution bottle, the water content and temperature probe is connected to the control system, the sampling pottery head is connected to the water distribution bottle, and the water distribution bottle is connected to the control system and the automatic monitoring system of water quality;

[0013] The automatic collection system of the groundwater in the saturated zone, collects the groundwater sample in the saturated zone and transmits to the automatic monitoring system of water quality; comprising a water level gauge, a submersible pump, the water level gauge and the submersible pump are connected to the control system;

[0014] The automatic cleaning system, for cleaning the water distribution bottle of the automatic collection system of the groundwater in the aeration zone and the automatic collection system of the soil groundwater; comprising a pure water bottle, a waste water bottle, a peristaltic pump; the pure water bottle is connected to the electromagnetic valve controlled by the control system through the peristaltic pump, the sampling bottle is also connected to the electromagnetic valve, and the waste water bottle is connected to the sampling bottle through the peristaltic pump.

[0015] The automatic monitoring system of water quality, realizes water quality monitoring through a monitoring probe, comprising a sampling bottle, a peristaltic pump and a monitoring probe, wherein the monitoring probe is arranged in the sampling bottle, and the monitoring probe provides a monitoring sample to the sampling bottle through the peristaltic pump;

[0016] The control system, comprising an industrial computer, a vacuum pump, an electromagnetic valve and control wires connected with each system, controls the operation of the above-mentioned systems, carries out data sampling and early warning; the control system dynamically adjusts the suction force of the vacuum pump according to the real-time water content and temperature, and controls the sampling efficiency of the unsaturated groundwater.

[0017] Further, the automatic collection system of the soil groundwater comprises a sampling pottery head, a water content and temperature probe and a water distribution bottle, and enters the soil layer in the borehole through the PVC-U monitoring pipe provided with the sampling pottery head, wherein the sampling pottery head is placed in the soil layer, the top of the sampling pottery head is connected to the water inlet of the bottom end of the water distribution bottle through the sampling pottery head water pipe, the water distribution bottle gas pipe at the upper end of the water distribution bottle is connected to the electromagnetic valve controlled by the control system, the water distribution bottle water inlet pipe at the upper end of the water distribution bottle is connected to the electromagnetic valve controlled by the control system, and the water outlet at the side end is connected to the electromagnetic valve of the automatic monitoring system of water quality through the water distribution bottle water pipe.

[0018] Further, the automatic collection system of the soil groundwater, the pottery head has a porous structure, and these small pores allow the soil solution to enter the interior of the pottery head under the action of pressure difference or natural diffusion, and the water content and temperature in the soil are monitored through the water content and temperature probe; the water content and temperature probe further comprises a water content probe and a temperature probe, the water content probe measures the water content of the soil based on the principle of capacitance, and the temperature probe measures the temperature of the soil based on the principle of thermal resistance. Through accurate water content and temperature monitoring and threshold setting, the leakage situation can be found in time and accurately, and when the content of pollutants is monitored to be increased, rapid early warning and prediction can be realized.

[0019] Further, the unsaturated zone groundwater automatic collection system comprises a sampling clay head, a water content and temperature probe, and a water distribution bottle, and the PVC-U monitoring pipe provided with the sampling clay head is used to enter the unsaturated zone of the borehole, wherein the sampling clay head is placed in the unsaturated zone, the top of the sampling clay head is connected to the water inlet at the bottom end of the water distribution bottle through the sampling clay head water pipe, the water distribution bottle gas pipe at the upper end of the water distribution bottle is connected to the electromagnetic valve controlled by the control system, the water distribution bottle water inlet pipe at the upper end of the water distribution bottle is connected to the electromagnetic valve controlled by the control system, and the water outlet at the side end is connected to the electromagnetic valve of the water quality automatic monitoring system through the water distribution bottle water pipe.

[0020] Further, the saturated zone groundwater automatic collection system is buried in the saturated layer through the PVC-U monitoring pipe provided with a filter, and the saturated zone groundwater automatic collection system is arranged in the PVC-U cutting pipe sleeved on the PVC-U monitoring pipe, so that the water quality can be accurately monitored; the control system is connected to the submersible pump to control the opening and closing of the submersible pump, and the submersible pump is connected to the electromagnetic valve of the water quality automatic monitoring system through the water outlet pipe.

[0021] Further, the filter is composed of a nylon screen and fine sand, wherein the nylon screen is arranged outside the PVC-U monitoring pipe and attached to the PVC-U cutting pipe, and the fine sand is arranged inside the PVC-U monitoring pipe and outside the PVC-U cutting pipe.

[0022] Further, the automatic cleaning system comprises a pure water bottle, a waste water bottle, and a peristaltic pump, wherein the peristaltic pump is divided into an automatic cleaning system pure water peristaltic pump and an automatic cleaning system waste water peristaltic pump, the pure water bottle is connected to the electromagnetic valve controlled by the control system through the automatic cleaning system pure water peristaltic pump, the electromagnetic valve is further connected to a sample bottle, and the waste water bottle is connected to the sample bottle through the automatic cleaning system waste water peristaltic pump.

[0023] Further, the water quality automatic monitoring system realizes water quality monitoring through a monitoring probe, and comprises a sample bottle, a water quality automatic monitoring system peristaltic pump, and a monitoring probe, wherein the monitoring probe extends into the sample bottle, and the sample bottle inputs a sample to be tested through the water quality automatic monitoring system peristaltic pump.

[0024] Further, in the water quality automatic monitoring system, the monitoring probe comprises any one or any combination of a water temperature monitoring probe, a pH monitoring probe, a conductivity monitoring probe, a turbidity monitoring probe, a dissolved oxygen monitoring probe, an oxidation-reduction potential monitoring probe, and a characteristic pollutant monitoring probe.

[0025] The application also provides a soil-unsaturated zone-saturated zone cross-media groundwater automatic monitoring method, which comprises the following steps:

[0026] Step 01: The control system is started, and water is pumped through the vacuum pump and the submersible pump;

[0027] Step 02, the vacuum pump draws water into the water distribution bottle through the sampling clay head; the water pumped by the submersible pump is directly into the sample bottle of the automatic water quality monitoring system;

[0028] Step 03, adjust the suction force of the vacuum pump to ensure the maximum sampling efficiency during sampling, so that the monitoring result is accurate and reliable;

[0029] The water content θ is described as a function formula of the matric potential ψ of the unsaturated zone through the soil moisture characteristic curve:

[0030]

[0031] According to the above formula, the efficiency formula of pumping is obtained:

[0032]

[0033] For the unsaturated hydraulic conductivity K(θ), use the following formula:

[0034]

[0035] Since the viscosity of water decreases with the increase of temperature, which directly affects the unsaturated hydraulic conductivity K(θ), considering the adaptability of the equipment to temperature changes, K(θ) is extended to K(θ,T):

[0036]

[0037] Where, θ: soil volume water content (m 3 / m 3 ) ; θ s : saturated water content (m 3 / m 3 ) ; θ r : residual water content (m 3 / m 3 ) ; K s : saturated hydraulic conductivity; l: empirical parameter (take 0.5) ; m: shape parameter, m = 1-1 / n; E a : activation energy, R: gas constant, T: temperature (℃).

[0038] Thus the matric potential of maximum efficiency is obtained, according to the actual water content and temperature, the size of the vacuum pump suction force is adjusted;

[0039] Step 04, the automatic water quality monitoring system detects water quality;

[0040] The control system starts the peristaltic pump of the automatic water quality monitoring system to extract the water sample in the water distribution bottle to the sample bottle to start monitoring reading;

[0041] Step 05, wash the water bottle and sample bottle; then start the cleaning system for cleaning, and at the same time, wash the water bottle and sample bottle.

[0042] Compared with the prior art, the beneficial effects of the present application are:

[0043] 1、The integrated device of the present application installs a layered soil, vadose zone and saturated zone cross-media groundwater sampling system in a single borehole, compared with the traditional multiple boreholes or independent monitoring equipment for different media, the soil-vadose zone-saturated zone cross-media groundwater sampling system is installed in the ground through a single borehole, and a set of monitoring equipment can complete the above-mentioned multi-layer cross-media groundwater sampling and monitoring, greatly saving the cost and improving the efficiency.

[0044] 2、The device procurement and installation and debugging cost is saved, the timeliness and synchronism of data acquisition are improved, the full-automatic monitoring of the vertical distribution of groundwater pollutants is realized, so that the whole groundwater monitoring work is more efficient, and the accuracy and reliability of water quality monitoring are improved.

[0045] 3、It can be long-term laid in the field, and through continuous sampling and monitoring, real-time uploading and feedback of data, long-term continuous observation of cross-media groundwater is facilitated.

[0046] 4、Through real-time monitoring of the water content in the ground, leakage can be found in time, and sampling and monitoring are carried out at the same time, which plays a warning role on pollution, so that measures can be taken in time to ensure that the further spread of pollutants to the saturated zone can be effectively prevented.

[0047] 5、The device can dynamically adjust the vacuum pumping force according to the real-time water content and temperature, improve the sampling efficiency of unsaturated groundwater, and improve the accuracy and reliability of monitoring. BRIEF DESCRIPTION OF DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows.

[0049] Figure 1 is a schematic diagram of the groundwater distribution and water quality monitoring realized by the present application.

[0050] Figure 2 is a whole schematic diagram of a soil-vadose zone-saturated zone cross-media groundwater automatic monitoring device of the present application.

[0051] Figure 3 is Figure 2 a schematic diagram of the A-A' cross-section structure in the device.

[0052] Figure 4 is Figure 2 a schematic diagram of the B-B' cross-section structure in the device.

[0053] Figure 5 Structure diagram of the automatic soil groundwater collection system of the present application.

[0054] Figure 6 For Figure 5 Structure diagram of the automatic soil groundwater collection system of the present application.

[0055] Figure 7 Structure diagram of the automatic soil groundwater collection system of the present application.

[0056] Figure 8 Structure diagram of the automatic soil groundwater collection system of the present application.

[0057] Figure 9 Structure diagram of the automatic soil groundwater collection system of the present application.

[0058] Figure 10 Structure diagram of the automatic soil groundwater collection system of the present application.

[0059] Figure 11 Structure diagram of the automatic soil groundwater collection system of the present application.

[0060] Figure: 1, water pipe; 101, peristaltic pump water pipe; 102, water pipe of water distribution bottle; 103, water pipe of water distribution bottle; 104, sampling pottery head water pipe; 105, water pipe of submersible pump; 106, water pipe of sampling bottle; 2, air pipe; 201, vacuum pump air pipe; 202, air pipe of water distribution bottle; 3, control wire; 301, peristaltic pump control wire; 302, water content and temperature control wire; 303, electromagnetic valve control wire; 304, vacuum pump control wire; 305, water level gauge control wire; 306, submersible pump control wire; 307, monitoring probe control wire; 4, PVC-U shell; 5, water content and temperature probe; 6, water distribution bottle; 7, sampling pottery head; 8, 60-mesh nylon screen; 9, fine sand; 10, PVC-U slit pipe; 11, water level gauge; 12, submersible pump; 13, peristaltic pump; 1301, automatic cleaning system pure water peristaltic pump; 1302, automatic cleaning system wastewater peristaltic pump; 1303, water quality automatic monitoring system peristaltic pump; 14, vacuum pump; 15, pure water bottle; 16, sampling bottle; 17, wastewater bottle; 18, monitoring probe. DETAILED DESCRIPTION

[0061] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application, and are not used to limit the present application.

[0062] It should be noted that all directional indications, such as upper, lower, left, right, front, rear, etc., are only used for the purpose of explanation and are not to be construed as indicating or implying relative importance or constituting a limitation of the described technical features.

[0063] It should also be noted that when an element is referred to as being "fixed" or "attached" to another element, it can be directly on the other element or intervening elements can also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can also be present.

[0064] In addition, the descriptions involving "first", "second" and the like in the present application are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or cannot be realized, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection required by the present application.

[0065] Please refer to Figure 1 , Figure 1 The automatic monitoring device for soil-aeration zone-saturated zone cross-media groundwater is realized by the present application, which comprises a saturated zone groundwater automatic collection system, an aeration zone groundwater automatic collection system, a soil groundwater automatic collection system, an automatic cleaning system, a water quality automatic monitoring system and a control system.

[0066] Please refer to Figures 2-4As shown, the automatic water collecting system of the saturated zone, the automatic water collecting system of the aeration zone, the automatic water collecting system of the soil, the automatic cleaning system, the automatic water quality monitoring system and the control system are shown in the figure. In the figure, the dotted line 1 represents the water pipe, the line 2 represents the air pipe, and the line 3 represents the control wire. The water pipe includes the peristaltic pump water pipe 101, the water inlet pipe of the water distribution bottle 102, the water outlet pipe of the water distribution bottle 103, the sampling pottery head water pipe 104, the water outlet pipe of the submersible pump 105, and the water inlet pipe of the sampling bottle 106, which are respectively connected to the peristaltic pump 13, the water distribution bottle 6, the sampling pottery head 7, the submersible pump 12 and the sampling bottle 16. The air pipe includes the vacuum pump air pipe 201 and the water distribution bottle air pipe 202, which are respectively connected to the vacuum pump 14 and the water distribution bottle 6. The control wire includes the peristaltic pump control wire 301, the water content and temperature control wire 302, the electromagnetic valve control wire 303, the vacuum pump control wire 304, the water level gauge control wire 305, the submersible pump control wire 306, and the monitoring probe control wire 307, which are respectively connected to the peristaltic pump 13, the water content and temperature probe, the electromagnetic valve, the vacuum pump 14, the water level gauge 11, the submersible pump 12, and the monitoring probe 18.

[0067] Figure 5 and Figure 6 As shown, the automatic water collecting system of the soil includes the sampling pottery head 7, the water content and temperature probe 5, and the water distribution bottle 6. The water content and temperature probe 5 is connected to the control system, the sampling pottery head 7 is connected to the water distribution bottle 6, and the water distribution bottle 6 is connected to the control system and the automatic water quality monitoring system.

[0068] The pottery head 7 has a porous structure, and these small pores allow soil solution to enter the interior of the pottery head under the action of pressure difference or natural diffusion, and the water content and temperature in the soil are monitored by the water content and temperature probe 5. The water content and temperature probe 5 includes a water content probe and a temperature probe. The water content probe measures the water content of the soil based on the principle of capacitance, and the temperature probe measures the temperature of the soil based on the principle of thermal resistance. Through accurate water content and temperature monitoring and threshold setting, leakage can be detected in time and accurately, and when the content of pollutants is detected to be increased, early warning and prediction can be made quickly.

[0069] Figure 7 As shown, the automatic water collecting system of the aeration zone also includes the sampling pottery head 7, the water content and temperature probe 5, and the water distribution bottle 6. The water content and temperature probe 5 is connected to the control system, the sampling pottery head 7 is connected to the water distribution bottle 6, and the water distribution bottle 6 is connected to the control system and the automatic water quality monitoring system.

[0070] The sampling pottery head 7 and the water content and temperature probe 5 of the automatic water collecting system of the aeration zone have the same functions and effects as the sampling pottery head 7 and the water content and temperature probe 5 of the automatic water collecting system of the soil.

[0071] Figure 8 As shown, it is an automatic collection system of groundwater in saturated zone, which collects groundwater samples in saturated zone and transmits to the automatic monitoring system of water quality; mainly including water level gauge 11 and submersible pump 12, both of which are connected to the control system.

[0072] Figure 9 As shown, it is an automatic cleaning system, which is used for cleaning the water distribution bottle of the automatic collection system of groundwater in vadose zone and the automatic collection system of soil groundwater; mainly including pure water bottle 15, waste water bottle 16, peristaltic pump 13 and control solenoid valve. Among them, the peristaltic pump 13 is further divided into automatic cleaning system pure water peristaltic pump 1301, automatic cleaning system waste water peristaltic pump 1302 and water quality automatic monitoring system peristaltic pump 1303.

[0073] The pure water bottle 15 is connected to the solenoid valve controlled by the control system through the automatic cleaning system pure water peristaltic pump 1301, which is controlled by the control system. The solenoid valve is also connected to the sample bottle 16, and the waste water bottle is connected to the sample bottle 16 through the automatic cleaning system waste water peristaltic pump 1302.

[0074] The water quality automatic monitoring system realizes water quality monitoring through monitoring probe, including sample bottle 16, water quality automatic monitoring system peristaltic pump 1303 and monitoring probe 18. Among them, the monitoring probe 18 extends into the sample bottle 16, and the sample bottle 16 inputs the sample to be tested through the water quality automatic monitoring system peristaltic pump 1303.

[0075] The control system is composed of industrial computer, vacuum pump 14, solenoid valve and control wire connecting each system, which controls the operation of the above system, data sampling and early warning; the control system dynamically adjusts the suction force of the vacuum pump 14 according to the real-time water content and temperature, and controls the sampling efficiency of the unsaturated groundwater.

[0076] As shown in Figure 5 As shown, the automatic collection system of soil groundwater puts the PVC-U monitoring pipe 4 with sampling pottery head 7 into the designated position, and the sampling pottery head 7 is prevented in the soil layer, and the top of the sampling pottery head is connected to the water inlet of the bottom end of the water distribution bottle 6 through the sampling pottery head water pipe 104; the water distribution bottle air pipe 202 at the upper end of the water distribution bottle 6 is connected to the solenoid valve controlled by the control system; the water distribution bottle water inlet pipe 102 at the upper end of the water distribution bottle 6 is connected to the solenoid valve controlled by the control system, and the water outlet at the side end is connected to the solenoid valve of the water quality automatic monitoring system through the water distribution bottle water pipe 102.

[0077] Specifically, the soil-vadose zone-saturated zone cross-media automatic monitoring method is realized, which includes the following steps:

[0078] Step 01, the control system is started, and the water is pumped by the vacuum pump and the submersible pump;

[0079] Step 02, the vacuum pump extracts water into the water distribution bottle through the sampling clay head; the water extracted by the submersible pump 12 is directly into the sampling bottle 16 of the automatic water quality monitoring system.

[0080] Step 03, adjust the suction force of the vacuum pump to ensure the maximum sampling efficiency during sampling, so that the monitoring result is accurate and reliable.

[0081] In the unsaturated zone, water is mainly extracted from the unsaturated zone by the negative pressure (suction) of the negative pressure (suction) of the sampling clay head, and the efficiency formula of the water extraction is:

[0082]

[0083] Where, Q: sampling flow rate (m / s); K(θ): unsaturated hydraulic conductivity (m / s); S: surface area of the clay head (m); L: thickness of the clay head (m); ψ: suction difference (Pa); ψ: suction of the vacuum pump (Pa); ψ: matric potential of the unsaturated zone (Pa). 3 2 c v v

[0084] From the above formula, the efficiency of water extraction is related to the suction difference, unsaturated hydraulic conductivity, surface area of the clay head, and thickness of the clay head. The property parameters of the clay head are determined during manufacturing, and by adjusting the size of the suction, the speed of water extraction can be changed. However, the greater the suction, the higher the efficiency of water extraction is not necessarily. With the increase of suction, the water content θ of the unsaturated zone decreases, and the unsaturated hydraulic conductivity also decreases sharply, and the efficiency of water extraction decreases. In addition, the change of temperature will also cause the change of unsaturated hydraulic conductivity K(θ), and the suction needs to be adjusted according to the actual real-time temperature.

[0085] Therefore, for different soil textures and different water contents, the device adjusts the suction of the vacuum pump to ensure the maximum water extraction efficiency. First, the model described by the water extraction efficiency formula (1) is simplified to the ideal state of horizontal one-dimensional situation, and combined with Richards formula, it can be written as:

[0086]

[0087] The unsaturated hydraulic conductivity K(θ) is described by the following formula:

[0088]

[0089] The water content θ is described as a function formula of the matric potential ψ of the unsaturated zone through the soil moisture characteristic curve:

[0090] ​​​​​

[0091] Because the viscosity of water decreases with the increase of temperature, which directly affects the unsaturated hydraulic conductivity K(0), considering the adaptability of the equipment to temperature changes, K(0) is extended to K(0, T):

[0092]

[0093] wherein, 0: soil volumetric water content (m 3 / m 3 ); 0 s : saturated water content (m 3 / m 3 ); 0 r : residual water content (m 3 / m 3 ); K s : saturated hydraulic conductivity; l: empirical parameter (take 0.5); m: shape parameter, m = 1-1 / n; E a : activation energy, R: gas constant, T: temperature (℃).

[0094] The maximum efficiency of the efficiency formula (2) of pumping can be solved by simultaneous equations (3), (4), (5) and (6). Therefore, when sampling in the unsaturated zone, the size of the vacuum pumping force should be adjusted according to the actual water content and the size of the temperature to ensure the maximum sampling efficiency when sampling.

[0095] As Figure 7 shown, the automatic groundwater sampling system in the aeration zone is to put the PVC-U monitoring pipe with the sampling clay head 7 into the designated position, that is, to place the sampling clay head 7 in the aeration zone, and the top of the sampling clay head is connected to the water inlet at the bottom end of the water distribution bottle 6 through the sampling clay head water pipe 104; the water distribution bottle gas pipe 202 at the upper end of the water distribution bottle 6 is connected to the electromagnetic valve controlled by the control system; the water distribution bottle water inlet pipe 102 at the upper end of the water distribution bottle 6 is connected to the electromagnetic valve controlled by the control system; and the water outlet at the side end is connected to the electromagnetic valve of the automatic water quality monitoring system through the water distribution bottle water pipe 102.

[0096] As Figure 8As shown, the saturated zone groundwater automatic collection system is embedded in the saturated layer through the PVC-U monitoring pipe 4 with filter, wherein the saturated zone groundwater automatic collection system is arranged in the PVC-U cutting pipe 10 sleeved in the PVC-U monitoring pipe 4 to accurately monitor the water quality; the saturated zone groundwater automatic collection system comprises a water level gauge 11 and a submersible pump 12; the control system is connected to the submersible pump 12 to control the opening and closing of the submersible pump 12. The filter is made of 60-mesh nylon screen 8 and 0.5-mm fine sand 9, the nylon screen 8 has two layers, one layer is arranged outside the PVC-U monitoring pipe 4, and the other layer is attached to the PVC-U cutting pipe 10, and the fine sand 9 is arranged in the PVC-U monitoring pipe 4 and located outside the PVC-U cutting pipe 10. The control system controls the start of the submersible pump 12 through the submersible pump control wire 306, and the submersible pump outlet pipe 105 is connected to the electromagnetic valve of the water quality automatic monitoring system.

[0097] Figure 9 As shown, the pure water bottle 15 of the automatic cleaning system is connected to the electromagnetic valve controlled by the control system through the automatic cleaning system pure water peristaltic pump 1301, the three outlets of the electromagnetic valve are respectively connected to the top water inlet of the sample bottle 16 through the water pipe 102 connected to two water distribution bottles 6 and the sample bottle water pipe 106, and the side water outlet of the sample bottle 16 is connected to the peristaltic pump water pipe 101 of the automatic cleaning system waste water peristaltic pump 1302 to realize waste water recycling.

[0098] Figure 10 As shown, the structure diagram of the water quality automatic monitoring system, as shown in the figure, the monitoring probe 18 of the water quality automatic monitoring system is placed in the sample bottle 16 through the top of the sample bottle, the top water inlet is connected to the sample bottle water inlet pipe 106, and the side water outlet is connected to the peristaltic pump water pipe 101.

[0099] Figure 11 As shown, the control system controls the water content probe 5, the water level gauge 11, the submersible pump 12, the peristaltic pump 13, the vacuum pump 14, the monitoring probe 18 and the electromagnetic valve through the industrial computer control peristaltic pump control wire. Specifically, the peristaltic pump control wire 301 is used to control the peristaltic pump 13, the water content and temperature control wire 302 is used to control the water content and temperature probe 5, the electromagnetic valve control wire 303 is used to control the electromagnetic valve, the vacuum pump control wire 304 is used to control the vacuum pump 14, the water level gauge control wire 305 is used to control the water level gauge 11, the submersible pump control wire 306 is used to control the submersible pump 12, and the monitoring probe control wire 307 is used to control the monitoring probe 18.

[0100] The industrial computer is a prior art, which can control the operation of the above components through programming.

[0101] In use, first, the control system sends a command to start the submersible pump, which sends the water in the water-saturated zone to the water quality automatic monitoring system sample bottle, starts the well washing, and if the water quality parameters reach stability for three times in succession, starts to record the monitoring results. The automatic cleaning system starts to work to clean the sample bottle.

[0102] While the water-saturated zone automatic sampling system is working, the control system first reads the water content and temperature of the unsaturated zone measured by the water content and temperature probe 5, then calculates the maximum sampling efficiency suction according to the real-time water content and temperature, and the controller opens the vacuum pump of the air gap and soil automatic sampling system to draw the space of the water distribution bottle and the sampling clay head to a specified negative pressure, so that the unsaturated zone groundwater enters the water distribution bottle.

[0103] Step 04, the water quality automatic monitoring system performs water quality detection; the water quality detection includes detection of Voc indicators in water, heavy metal component analysis and content analysis, and microbial content, the control system starts the peristaltic pump of the water quality automatic monitoring system to extract the water sample in the water distribution bottle to the sample bottle to start monitoring reading, these means are prior art and will not be described here.

[0104] Step 05, clean the water distribution bottle and the sample bottle; then start the cleaning system to clean the water distribution bottle and the sample bottle. The water distribution bottle and the sample bottle are cleaned to ensure the accuracy of the next detection and avoid the influence of residues on the detection.

[0105] When a precipitation event or a leakage event occurs, the water content probe of the control system detects the change in water content in the unsaturated zone, and then automatically starts the above-mentioned steps to work.

[0106] In summary, the present application designs an integrated device, installs a layered soil, air gap, and water-saturated zone cross-media groundwater sampling system in a single borehole, and uses a set of monitoring equipment to complete the above-mentioned multi-layer cross-media groundwater sampling and monitoring, greatly saving the cost and improving the efficiency; realizes full-automatic monitoring of the vertical distribution of groundwater pollutants, so that the whole groundwater monitoring work is more efficient, and the accuracy and reliability of water quality monitoring are improved.

[0107] The present application can timely discover leakage and simultaneously sample and monitor by real-time monitoring of the water content underground, and has a warning effect on pollution, so that measures can be taken in time to ensure that the pollutants can be effectively prevented from further spreading to the water-saturated zone. In particular, the vacuum pump suction can be dynamically adjusted according to the real-time water content and temperature to improve the sampling efficiency of the unsaturated groundwater and improve the accuracy and reliability of the monitoring.

[0108] At the same time, the present application can be long-term laid in the field by automatic monitoring, and the data can be uploaded and fed back in real time through continuous sampling and monitoring, so as to facilitate long-term continuous observation of the cross-media groundwater.

[0109] The above merely provides the application examples, and does not limit the patent scope of the application. Any equivalent structure or equivalent process transformation based on the content of the application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the application.

Claims

1. An automatic monitoring method for groundwater across soil-vadose zone-saturated zone media, characterized in that, An automatic monitoring method for groundwater across soil, vadose zone, and saturated zone includes the following steps: Step 01: The control system is activated, and water is pumped using a vacuum pump and a submersible pump. Step 02: The vacuum pump draws water into the water distribution bottle through the sampling clay head; the submersible pump draws water directly into the sample bottle of the automatic water quality monitoring system. Step 03: Adjust the vacuum pump suction to ensure maximum sampling efficiency during sampling, so as to make the monitoring results accurate and reliable; The water content θ, together with the soil moisture characteristic curve, can be described as a function of the unsaturated zone matrix potential ψ: Based on the above formula, the pumping efficiency formula can be obtained: For unsaturated hydraulic conductivity K(θ), use the following formula: Since the viscosity of water decreases with increasing temperature, directly affecting the unsaturated hydraulic conductivity K(θ), considering the equipment's adaptability to temperature changes, K(θ) is extended to K(θ,T): Where θ: soil volumetric water content (m) 3 / m 3 ;θ s : Saturated water content m 3 / m 3 ;θ r Residual moisture content m 3 / m 3 Ks: Saturated hydraulic conductivity; l: Empirical parameter, taken as 0.5; m: Shape parameter, m = 1 - 1 / n; Ea: Activation energy; R: Gas constant; T: Temperature in °C. This yields the matrix potential with maximum efficiency, and the suction force of the vacuum pump is adjusted according to the actual moisture content and temperature. Step 04: The automatic water quality monitoring system performs water quality testing; The control system starts the peristaltic pump of the automatic water quality monitoring system to extract the water sample from the water distribution bottle into the test bottle and begin monitoring and reading. Step 05: Clean the water mixing bottle and the sample bottle; then start the cleaning system to clean them, and clean the water mixing bottle and the sample bottle at the same time.

2. The automatic monitoring method for groundwater across soil-vadose zone-saturated zone as described in claim 1, characterized in that, While the automatic water-saturated zone collection system is working, the control system first reads the water content and temperature of the unsaturated zone measured by the water content and temperature probes. Then, based on the real-time water content and temperature, it calculates the suction force for maximum sampling efficiency. The controller then turns on the vacuum pump of the vadose zone and the automatic soil groundwater collection system, drawing the space between the water distribution bottle and the sampling clay head to a specified negative pressure, so that the groundwater in the unsaturated zone enters the water distribution bottle.

3. An apparatus for implementing the automatic monitoring method for groundwater across soil-vadose zone-saturated zone as described in claim 1, characterized in that, The device includes an automatic soil groundwater sampling system installed in the soil layer, an automatic vadose zone groundwater sampling system installed in the vadose zone, an automatic water-saturated zone groundwater sampling system installed in the water-saturated zone, an automatic cleaning system, an automatic water quality monitoring system, and a control system. The automatic soil groundwater sampling system, the automatic vadose zone groundwater sampling system, and the automatic water-saturated zone groundwater sampling system are located within a single borehole, arranged vertically, and are respectively connected to the automatic cleaning system and the automatic water quality monitoring and control system. Through the layered soil, vadose zone, and water-saturated zone groundwater sampling systems within a single borehole, and their interconnection with the shared automatic cleaning system and automatic water quality monitoring and control system, synchronous monitoring across different media is achieved. The soil groundwater automatic sampling system collects groundwater samples from the soil and transmits them to the water quality automatic monitoring system. It includes a sampling clay head, a moisture content and temperature probe, and a water dispensing bottle. The moisture content and temperature probe are connected to the control system, the sampling clay head is connected to the water dispensing bottle, and the water dispensing bottle is connected to both the control system and the water quality automatic monitoring system. An automatic groundwater sampling system for the vadose zone collects groundwater samples from the vadose zone and transmits them to an automatic water quality monitoring system. The system includes a sampling clay head, a moisture content and temperature probe, and a water distribution bottle. The moisture content and temperature probe are connected to the control system, the sampling clay head is connected to the water distribution bottle, and the water distribution bottle is connected to both the control system and the automatic water quality monitoring system. An automatic groundwater collection system for saturated zones collects groundwater samples from saturated zones and transmits them to an automatic water quality monitoring system; it includes a water level gauge and a submersible pump, both of which are connected to the control system. An automatic cleaning system is used to clean the water bottles of the automatic groundwater collection system in the vadose zone and the automatic groundwater collection system in the soil. It includes a pure water bottle, a waste water bottle, and a peristaltic pump. The pure water bottle is connected to a solenoid valve controlled by the control system through the peristaltic pump. The sample bottle is also connected to the solenoid valve. The waste water bottle is connected to the sample bottle through the peristaltic pump. The automatic water quality monitoring system monitors water quality through a monitoring probe. It includes a sample bottle, a peristaltic pump, and a monitoring probe. The monitoring probe is installed in the sample bottle, and the peristaltic pump provides the sample to the sample bottle. The control system comprises an industrial computer, a vacuum pump, solenoid valves, and control wires connecting each system. It controls the operation of the aforementioned systems, performs data sampling, and provides early warnings. The control system dynamically adjusts the suction force of the vacuum pump based on real-time moisture content and temperature to control the sampling efficiency of unsaturated groundwater.

4. The apparatus for automatic monitoring of groundwater across soil-vadose zone-saturated zone according to claim 3, characterized in that, The automatic soil and groundwater sampling system includes a sampling clay head, moisture and temperature probes, and a water distribution bottle. The system enters the soil layer of the borehole through a PVC-U monitoring tube equipped with the sampling clay head. The sampling clay head is placed in the soil layer, and its top is connected to the water inlet at the bottom of the water distribution bottle via a water pipe. The air pipe at the top of the water distribution bottle is connected to a solenoid valve controlled by the control system. The water inlet pipe at the top of the water distribution bottle is also connected to a solenoid valve controlled by the control system. The water outlet at the side is connected to a solenoid valve of the automatic water quality monitoring system via a water pipe.

5. The apparatus for automatic monitoring of groundwater across soil-vadose zone-saturated zone according to claim 3, characterized in that, The automatic groundwater acquisition system in the vadose zone includes a sampling clay head, moisture content and temperature probes, and a water distribution bottle. The system enters the vadose zone of the borehole through a PVC-U monitoring tube equipped with the sampling clay head. The sampling clay head is placed in the vadose zone, and its top is connected to the inlet at the bottom of the water distribution bottle via a sampling clay head water pipe. The air pipe at the top of the water distribution bottle is connected to a solenoid valve controlled by the control system. The water inlet pipe at the top of the water distribution bottle is also connected to a solenoid valve controlled by the control system. The water outlet at the side is connected to a solenoid valve of the automatic water quality monitoring system via a water distribution bottle water pipe.

6. The apparatus for automatic monitoring of groundwater across soil-vadose zone-saturated zone according to claim 3, characterized in that, The automatic groundwater collection system for the saturated zone is installed in the saturated layer through a PVC-U monitoring pipe with a filter. The system is set inside a PVC-U slotted pipe fitted inside the PVC-U monitoring pipe to accurately monitor the water quality. The control system is connected to the submersible pump to control the opening and closing of the submersible pump. The submersible pump is connected to the solenoid valve of the automatic water quality monitoring system through the outlet pipe.

7. The apparatus for automatic monitoring of groundwater across soil-vadose zone-saturated zone according to claim 6, characterized in that, The filter consists of a nylon screen and fine sand. The nylon screen is placed outside the PVC-U monitoring tube and attached to the PVC-U slotted tube, while the fine sand is placed inside the PVC-U monitoring tube and located outside the PVC-U slotted tube.

8. The apparatus for automatic monitoring of groundwater across soil-vadose zone-saturated zone according to claim 3, characterized in that, An automatic cleaning system is used to clean the water bottles of the automatic vadose zone groundwater collection system and the automatic soil groundwater collection system. It includes a pure water bottle, a wastewater bottle, and a peristaltic pump. The peristaltic pump is further divided into a pure water peristaltic pump and a wastewater peristaltic pump for the automatic cleaning system. The pure water bottle is connected to a solenoid valve controlled by the control system through the pure water peristaltic pump of the automatic cleaning system. The solenoid valve is connected to a sample bottle. The wastewater bottle is connected to the sample bottle through the wastewater peristaltic pump of the automatic cleaning system.

9. The apparatus for automatic monitoring of groundwater across soil-vadose zone-saturated zone according to claim 3, characterized in that, The automatic water quality monitoring system monitors water quality through a monitoring probe. It includes a sample bottle, a peristaltic pump of the automatic water quality monitoring system, and a monitoring probe. The monitoring probe extends into the sample bottle, and the sample bottle is then fed with the sample to be tested through the peristaltic pump of the automatic water quality monitoring system.

10. The apparatus for automatic monitoring of groundwater across soil-vadose zone-saturated zone according to claim 9, characterized in that, The automatic water quality monitoring system includes any one or any combination of monitoring probes for water temperature, pH, conductivity, turbidity, dissolved oxygen, oxidation-reduction potential, and characteristic pollutants.

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