Soil-aeration zone-saturated zone cross-medium underground water automatic monitoring device and monitoring method

Abstract

The invention 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. According to the device and the method, the water quality of the soil layer and the aeration zone layer is monitored comprehensively, soil-aeration zone-saturated zone multi-layer cross-medium underground water sampling monitoring can be completed, the cost is greatly saved, and the efficiency is improved.

Description

Technical Field

[0001] This application relates to the technical field of water quality monitoring, and particularly to an automatic monitoring device and method for soil-aeration zone-saturated zone cross-media groundwater for multi-environment monitoring. Background Art

[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. The soil, aeration 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, that is, water stored below the surface. The water stored below the surface includes the water in the soil layer, the water in the aeration zone, and the groundwater in the saturated zone. Narrowly defined, groundwater only refers to the groundwater in the saturated zone.

[0003] In recent years, groundwater pollution has also become a matter of great concern. Pollutants in the soil can enter the saturated zone through the aeration zone, thus polluting the groundwater.

[0004] The environmental automatic monitoring methods for narrow-sense groundwater have become increasingly mature. For example, a smart monitoring device for automatic monitoring, detection, and early warning of groundwater disclosed in Patent Application No. 202210142180.1 is an intelligent device for automatic, multi-dimensional, and long-term monitoring of groundwater, automatic detection, and threshold alarm in observation wells during geological exploration and underground engineering construction. Its structure includes a data storage and control module, a data transmission and connection module, and a measurement unit module. Another example is a method for monitoring groundwater circulation elements based on a full-drainage karst spring in the north disclosed in Patent Application No. 202211717217.5, which includes: measuring the groundwater level within the surveyed area, investigating the groundwater flow direction using a groundwater flow velocity and direction detector, and determining the spring domain range in combination with geological and hydrogeological information; using a monitoring device to monitor within the spring domain range to obtain water volume information; regularly sampling precipitation, karst groundwater, and spring water at typical locations within the spring domain range to obtain sampling information; transmitting the water volume information and sampling information to a terminal processor for data processing to study the response relationship between groundwater level information, surface water, and spring water flow information and precipitation information, and supplemented by the chlorine mass balance method to determine the ineffective precipitation in the spring domain, determine the precipitation infiltration coefficient, and reveal the circulation mechanism of karst groundwater.

[0005] Therefore, monitoring the soil-aeration zone-saturated zone cross-media groundwater can provide a more comprehensive understanding of 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, but cannot monitor the water quality of the soil layer and the vadose zone. Therefore, it is urgent to improve it to comprehensively and accurately monitor the groundwater situation and promote the good development of environmental protection. Summary of the invention

[0007] Based on this, the primary purpose of the present invention is to provide a soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device and monitoring method. The device and method monitor the water quality of the soil layer and the vadose zone layer, and the monitoring is comprehensive. It can also complete the groundwater sampling and monitoring of the soil-vadose zone-saturated zone multi-layer cross-medium, which greatly saves costs and improves efficiency.

[0008] Another object of the present invention is to provide a soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device and monitoring method, which can realize fully automatic monitoring of the vertical distribution of groundwater pollutants, thereby making the entire groundwater monitoring work more efficient, and can improve the timeliness and synchronization of data acquisition, thereby improving the accuracy and reliability of water quality monitoring.

[0009] To achieve the above object, the technical solution of the present invention is:

[0010] A soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device, the device comprising a soil groundwater automatic collection system arranged in a soil layer, a vadose zone groundwater automatic collection system arranged in a vadose zone, a saturated zone groundwater automatic collection system arranged in a saturated zone, an automatic cleaning system, an automatic water quality 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, arranged in an upper and lower 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 and the automatic water quality monitoring system and control system; through the soil, vadose zone, and saturated zone groundwater sampling systems arranged in layers in a single borehole, and linked with the shared automatic cleaning system and the automatic water quality monitoring system and control system, cross-medium synchronous monitoring is realized;

[0011] The soil and groundwater automatic collection system collects soil and groundwater samples 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 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 the control system and the water quality automatic monitoring system;

[0012] The vadose zone groundwater automatic sampling system, the vadose zone automatic sampling system, collects groundwater samples in the vadose zone 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 distribution bottle. The moisture content and temperature probe is connected to the control system, the sampling clay head is connected to the water distribution bottle, and the water distribution bottle is also connected to the control system and the water quality automatic monitoring system;

[0013] The saturated zone groundwater automatic sampling system, collects groundwater samples in the saturated zone and transmits them to the water quality automatic monitoring system; it includes a water level gauge and a submersible pump, and both the water level gauge and the submersible pump are connected to the control system;

[0014] The automatic cleaning system is used to clean the water distribution bottles of the vadose zone groundwater automatic sampling system and the soil groundwater automatic sampling system; it includes a pure water bottle, a waste water bottle, and a peristaltic pump; the pure water bottle is connected to an electromagnetic valve controlled by the control system through the peristaltic pump, the sample measurement bottle is also connected to the electromagnetic valve, and the waste water bottle is connected to the sample measurement bottle through the peristaltic pump.

[0015] The water quality automatic monitoring system realizes water quality monitoring through monitoring probes, and includes a sample measurement bottle, a peristaltic pump, and monitoring probes. Among them, the monitoring probes are arranged in the sample measurement bottle, and the monitoring samples are provided to the sample measurement bottle through the peristaltic pump;

[0016] The control system consists of an industrial control computer, a vacuum pump, electromagnetic valves, and control wires connecting each system, controls the operation of the above systems, conducts data sampling and early warning; the control system dynamically adjusts the vacuum pump suction according to the real-time moisture content and temperature to control the sampling efficiency of unsaturated groundwater.

[0017] Furthermore, the soil groundwater automatic sampling system includes a sampling clay head, a moisture content and temperature probe, and a water distribution bottle. It enters the soil layer of the borehole through a PVC-U monitoring pipe equipped with a sampling clay head. Among them, the sampling clay head is placed in the soil layer, and its top is connected to the water inlet at the bottom end of the water distribution bottle through a sampling clay head water pipe; the water distribution bottle gas pipe at the upper end of the water distribution bottle is connected to an 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 an electromagnetic valve controlled by the control system; the water outlet at the side end is connected to the electromagnetic valve of the water quality automatic monitoring system through a water distribution bottle water pipe.

[0018] Furthermore, in the soil groundwater automatic sampling system, the clay head has a porous structure. These tiny pores allow the soil solution to enter the interior of the clay head under the action of a pressure difference or natural diffusion. The moisture content and temperature in the soil are monitored through the moisture content and temperature probe; the moisture content and temperature probe also includes a moisture content probe and a temperature probe. The moisture content probe measures the moisture content of the soil based on the capacitance principle, and the temperature probe measures the temperature of the soil based on the thermal resistance principle. Through accurate moisture content and temperature monitoring and threshold setting, leakage situations can be discovered in a timely and accurate manner, and when the pollutant content increases, early warning can be quickly issued.

[0019] Further, the vadose zone groundwater automatic sampling system includes a sampling clay head, a water content and temperature probe, and a water distribution bottle, and enters the vadose zone of the borehole through a PVC-U monitoring pipe equipped with a sampling clay head. Among them, the sampling clay head is placed in the vadose zone, and its top is connected to the water inlet at the bottom end of the water distribution bottle through a sampling clay head water pipe; the water distribution bottle air pipe at the upper end of the water distribution bottle is connected to an 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 an electromagnetic valve controlled by the control system; the water outlet at the side end is connected to the electromagnetic valve of the water quality automatic monitoring system through a water distribution bottle water pipe.

[0020] Further, the saturated zone groundwater automatic sampling system is buried in the saturated zone through a PVC-U monitoring pipe with a filter, and the saturated zone groundwater automatic sampling system is arranged in a PVC-U slotted pipe sleeved in the PVC-U monitoring pipe to accurately monitor the water quality; the control system is connected to a 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 a water outlet pipe.

[0021] Furthermore, the filter is composed of a nylon screen and fine sand. Among them, the nylon screen is arranged outside the PVC-U monitoring pipe and attached to the PVC-U slotted pipe, and the fine sand is arranged inside the PVC-U monitoring pipe and outside the PVC-U slotted pipe.

[0022] Further, the automatic cleaning system includes a pure water bottle, a waste water bottle, and a peristaltic pump; among them, the peristaltic pump is divided into a pure water peristaltic pump of the automatic cleaning system and a waste water peristaltic pump of the automatic cleaning system; the pure water bottle is connected to an electromagnetic valve controlled by the control system through the pure water peristaltic pump of the automatic cleaning system, and the electromagnetic valve is also connected to a sample measurement bottle, and the waste water bottle is connected to the sample measurement bottle through the waste water peristaltic pump of the automatic cleaning system.

[0023] Further, the water quality automatic monitoring system realizes water quality monitoring through monitoring probes, and includes a sample measurement bottle, a water quality automatic monitoring system peristaltic pump, and monitoring probes. Among them, the monitoring probes extend into the sample measurement bottle, and the sample measurement bottle inputs the sample to be measured through the water quality automatic monitoring system peristaltic pump.

[0024] Furthermore, in the water quality automatic monitoring system, the monitoring probes include any one or any combination of water temperature, pH, conductivity, turbidity, dissolved oxygen, oxidation-reduction potential, and characteristic pollutant monitoring probes.

[0025] The present invention also provides a soil-vadose zone-saturated zone cross-media groundwater automatic monitoring method, which includes the following steps:

[0026] Step 01, the control system is started, and pumping is carried out through a vacuum pump and a submersible pump;

[0027] Step 02: The vacuum pump pumps water into the water distribution bottle through the sampling clay head; the water pumped by the submersible pump directly goes into the sample measuring bottle of the water quality automatic monitoring system.

[0028] Step 03: Adjust the suction of the vacuum pump to ensure the maximum sampling efficiency during sampling, so as to make the monitoring results accurate and reliable.

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

[0030]

[0031] Solve the pumping efficiency formula according to the above formula:

[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, expand K(θ) to K(θ,T):

[0036]

[0037] Where, θ: soil volumetric 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 (°C).

[0038] Thus, the matrix potential of the maximum efficiency is obtained, and the suction of the vacuum pump is adjusted according to the actual water content and temperature.

[0039] Step 04: The water quality automatic monitoring system conducts water quality detection.

[0040] The control system starts the peristaltic pump of the water quality automatic monitoring system, extracts the water sample in the water distribution bottle into the sample measuring bottle, and starts monitoring and reading.

[0041] Step 05: Clean the water preparation bottle and the sample measurement bottle; then start the cleaning system for cleaning, and clean the water preparation bottle and the sample measurement bottle at the same time.

[0042] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0043] 1. Through the integrated device of the present invention, a cross-media groundwater sampling system for soil, vadose zone, and saturated zone is installed in a layered manner in a single borehole. Compared with the traditional multiple boreholes or independent monitoring devices set for different media respectively, the cross-media groundwater sampling system for soil-vadose zone-saturated zone is installed underground through a single borehole, and a set of monitoring devices can be used to complete the above-mentioned multi-layer cross-media groundwater sampling and monitoring, greatly saving costs and improving efficiency.

[0044] 2. It saves the costs of equipment procurement, installation, and commissioning, improves the timeliness and synchronization of data acquisition, realizes the full-automatic monitoring of the vertical distribution of groundwater pollutants, thereby making the entire groundwater monitoring work more efficient, and improving the accuracy and reliability of water quality monitoring.

[0045] 3. It can be deployed in the field for a long time. Through continuous sampling and monitoring, data is uploaded and fed back in real time, facilitating the long-term continuous observation of cross-media groundwater.

[0046] 4. By real-time monitoring of the water content in the ground, leakage can be detected in a timely manner. At the same time, through sampling and monitoring, it plays a warning role for pollution, so as to take measures in a timely manner to ensure that pollutants can be effectively prevented from further spreading to the saturated zone.

[0047] 5. The device of the present invention can dynamically adjust the suction of the vacuum pump according to the real-time water content and temperature, improve the sampling efficiency of unsaturated groundwater, and improve the accuracy and reliability of monitoring. Description of the Drawings

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments.

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

[0050] Figure 2 It is an overall schematic diagram of a cross-media groundwater automatic monitoring device for soil-vadose zone-saturated zone of the present invention.

[0051] Figure 3 It is Figure 2 The schematic diagram of the cross-sectional structure of A-A' in

[0052] Figure 4 It is Figure 2 The schematic diagram of the cross-sectional structure of B-B' in

[0053] Figure 5 It is a schematic structural diagram of the soil and groundwater automatic collection system of the present invention.

[0054] Figure 6 is Figure 5 The enlarged structural diagram at position C in

[0055] Figure 7 It is a schematic structural diagram of the vadose zone groundwater automatic collection system of the present invention.

[0056] Figure 8 It is a schematic structural diagram of the saturated zone groundwater automatic collection system of the present invention.

[0057] Figure 9 It is a schematic structural diagram of the automatic cleaning system of the present invention.

[0058] Figure 10 It is a schematic structural diagram of the water quality automatic monitoring system of the present invention.

[0059] Figure 11 It is a schematic structural diagram of the control system of the present invention.

[0060] In the figure: 1. Water pipe; 101. Peristaltic pump water pipe; 102. Water inlet pipe of the water distribution bottle; 103. Water outlet pipe of the water distribution bottle; 104. Water pipe of the sampling clay head; 105. Water outlet pipe of the submersible pump; 106. Water inlet pipe of the sample measurement bottle; 2. Air pipe; 201. Vacuum pump air pipe; 202. Air pipe of the water distribution bottle; 3. Control wire; 301. Control wire of the peristaltic pump; 302. Control wire of the water content and temperature; 303. Control wire of the electromagnetic valve; 304. Control wire of the vacuum pump; 305. Control wire of the water level gauge; 306. Control wire of the submersible pump; 307. Control wire of the monitoring probe; 4. PVC-U housing; 5. Water content and temperature probe; 6. Water distribution bottle; 7. Sampling clay head; 8. 60-mesh nylon screen; 9. Fine sand; 10. PVC-U slotted pipe; 11. Water level gauge; 12. Submersible pump; 13. Peristaltic pump; 1301. Pure water peristaltic pump of the automatic cleaning system; 1302. Waste water peristaltic pump of the automatic cleaning system; 1303. Peristaltic pump of the water quality automatic monitoring system; 14. Vacuum pump; 15. Pure water bottle; 16. Sample measurement bottle; 17. Waste water bottle; 18. Monitoring probe. Specific embodiments

[0061] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0062] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship, movement conditions, etc. between components in a specific posture (as shown in the attached drawings). If the specific posture changes, the directional indications will also change accordingly.

[0063] It should also be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as "connected to" another element, it can be directly connected to the other element or there may be an intermediate element at the same time.

[0064] In addition, the descriptions involving "first", "second", etc. in the present invention are only for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions conflicts with each other or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0065] Please refer to Figure 1 , Figure 1 which is the soil-unsaturated zone-saturated zone cross-media groundwater automatic monitoring device implemented by the present invention. The device includes a saturated zone groundwater automatic collection system, an unsaturated 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] Refer to Figures 2 - 4As shown in the figure, it is a composition diagram of the saturated zone groundwater automatic collection system, unsaturated zone groundwater automatic collection system, soil groundwater automatic collection system, automatic cleaning system, water quality automatic monitoring system and control system implemented by the present invention. In the figure, the dotted line indicated by 1 represents a water pipe, 2 represents an air pipe, and 3 represents a control wire. Among them, the water pipe further includes a peristaltic pump water pipe 101, a water inlet pipe 102 of the water distribution bottle, a water outlet pipe 103 of the water distribution bottle, a water pipe 104 of the sampling clay head, a water outlet pipe 105 of the submersible pump, and a water inlet pipe 106 of the sample measurement bottle, which are respectively connected to the peristaltic pump 13, the water distribution bottle 6, the sampling clay head 7, the submersible pump 12 and the sample measurement bottle 16; the air pipe includes a vacuum pump air pipe 201 and a 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 a peristaltic pump control wire 301, a moisture content and temperature control wire 302, an electromagnetic valve control wire 303, a vacuum pump control wire 304, a water level gauge control wire 305, a submersible pump control wire 306, and a monitoring probe control wire 307, which are respectively electrically connected to the peristaltic pump 13, the moisture 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 in the figure, the soil groundwater automatic collection system includes a sampling clay head 7, a moisture content and temperature probe 5, and a water distribution bottle 6. The moisture content and temperature probe 5 is connected to the control system, the sampling clay head 7 is connected to the water distribution bottle 6, and the water distribution bottle 6 is further connected to the control system and the water quality automatic monitoring system.

[0068] The clay head 7 has a porous structure. These tiny pores allow the soil solution to enter the interior of the clay head under the action of a pressure difference or natural diffusion. The moisture content and temperature in the soil are monitored through the moisture content and temperature probe 5; the moisture content and temperature probe 5 further includes a moisture content probe and a temperature probe. The moisture content probe measures the moisture content of the soil based on the capacitance principle, and the temperature probe measures the temperature of the soil based on the thermal resistance principle. Through accurate monitoring of moisture content and temperature and threshold setting, leakage situations can be discovered in a timely and accurate manner, and rapid early warning can be issued when the pollutant content is monitored to increase.

[0069] Figure 7 As shown in the figure, the unsaturated zone groundwater automatic collection system also includes a sampling clay head 7, a moisture content and temperature probe 5 and a water distribution bottle 6. The moisture content and temperature probe 5 is connected to the control system, the sampling clay head 7 is connected to the water distribution bottle 6, and the water distribution bottle 6 is further connected to the control system and the water quality automatic monitoring system.

[0070] The sampling clay head 7 and the moisture content and temperature probe 5 of the unsaturated zone groundwater automatic collection system have the same functions and roles as the sampling clay head 7 and the moisture content and temperature probe 5 of the soil groundwater automatic collection system.

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

[0072] Figure 9 As shown, it is an automatic cleaning system for cleaning the water distribution bottles of the vadose zone groundwater automatic collection system and the soil groundwater automatic collection system. It mainly includes a pure water bottle 15, a waste water bottle 16, a peristaltic pump 13 and control electromagnetic valves. Among them, the peristaltic pump 13 is further divided into a pure water peristaltic pump 1301 for the automatic cleaning system, a waste water peristaltic pump 1302 for the automatic cleaning system, and a peristaltic pump 1303 for the water quality automatic monitoring system.

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

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

[0075] The control system is composed of an industrial control computer, a vacuum pump 14, electromagnetic valves and control wires connecting each system, and controls the operation of the above systems, conducts data sampling and gives early warnings; the control system dynamically adjusts the suction of the vacuum pump 14 according to the real-time moisture content and temperature to control the sampling efficiency of unsaturated groundwater.

[0076] As Figure 5 As shown, the soil groundwater automatic collection system inserts the PVC-U monitoring pipe 4 equipped with a sampling clay head 7 into the designated position. The sampling clay head 7 is placed in the soil layer, and its top 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 air 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 water quality automatic monitoring system through the water distribution bottle water pipe 102.

[0077] Specifically, the method for realizing the automatic monitoring of cross-media groundwater in soil-vadose zone-saturated zone includes the following steps:

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

[0079] Step 02: The vacuum pump pumps water into the water distribution bottle through the sampling clay head; the water pumped by the submersible pump 12 directly reaches the sample measuring bottle 16 of the water quality automatic monitoring system.

[0080] Step 03: Adjust the suction of the vacuum pump to ensure the maximum sampling efficiency during sampling, so as to make the monitoring results accurate and reliable.

[0081] In the unsaturated zone, mainly under the action of the matrix potential (negative pressure), water is mainly extracted from the unsaturated zone through the negative pressure (suction) evacuated inside the sampling clay head. The efficiency formula for water pumping is as follows:

[0082]

[0083] Where, Q: Sampling flow rate (m 3 / s); K(θ): Unsaturated hydraulic conductivity (m / s); Surface area of the clay head (m 2 ); ψ c = ψ v - ψ: Suction difference (Pa); L: Thickness of the clay head (m); ψ v : Suction of the vacuum pump (Pa); ψ: Matrix potential of the unsaturated zone (Pa).

[0084] As can be seen from the above formula, the efficiency of water pumping is related to the suction difference, unsaturated hydraulic conductivity, surface area of the clay head, and thickness of the clay head, etc. The property parameters of the clay head have been determined during manufacturing. By adjusting the magnitude of the suction, the water pumping speed can be changed. However, the greater the suction, the higher the water pumping efficiency is not necessarily. As the suction increases, the water content θ in the unsaturated zone decreases, and the unsaturated hydraulic conductivity will also decrease sharply accordingly, and the water pumping efficiency will become lower. In addition, the change in temperature will also cause the unsaturated hydraulic conductivity K(θ) to change, and it is also necessary to consider adjusting the suction according to the actual real-time temperature.

[0085] Therefore, for different soil textures and different water contents, this device ensures the maximum water pumping efficiency by intelligently adjusting the suction extracted by the vacuum pump. First, simplify the model described by the water pumping efficiency formula (1) to the ideal state in the horizontal one-dimensional case and combine it with the Richards formula, which can be written as:

[0086]

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

[0088]

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

[0090]

[0091] Since the viscosity of water decreases with increasing temperature, it directly affects the unsaturated hydraulic conductivity K(θ). Considering the adaptability of the equipment to temperature changes, K(θ) is expanded to K(θ,T):

[0092]

[0093] Where, θ: soil volume moisture content (m 3 / m 3 );θ s :Saturated moisture content (m 3 / m 3 );θ r :Residual moisture 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] Formulas (3), (4), (5) and (6) can be used to solve the maximum efficiency matrix potential of the pumping efficiency formula (2). Therefore, when sampling in the unsaturated zone, the suction force of the vacuum pump should be adjusted according to the actual water content and temperature to ensure the maximum sampling efficiency during sampling.

[0095] like Figure 7 As shown, the automatic groundwater collection system in the aeration zone moves the PVC-U monitoring tube equipped with the sampling clay head 7 into the specified position, that is, the sampling clay head 7 is placed in the aeration zone, and its top 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 air 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; 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 102.

[0096] like Figure 8As shown in the figure, the automatic groundwater collection system in the saturated zone is buried in the saturated layer through a PVC-U monitoring pipe 4 with a filter. Among them, the automatic groundwater collection system in the saturated zone is arranged in a PVC-U slotted pipe 10 sleeved inside the PVC-U monitoring pipe 4 to accurately monitor the water quality; the automatic groundwater collection system in the saturated zone includes 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 a 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 slotted pipe 10. The fine sand 9 is arranged inside the PVC-U monitoring pipe 4 and outside the PVC-U slotted 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 automatic water quality monitoring system.

[0097] Figure 9 As shown in the figure, the pure water bottle 15 of the automatic cleaning system is connected to the electromagnetic valve controlled by the control system through the pure water peristaltic pump 1301 of the automatic cleaning system. The three outlets of the electromagnetic valve are respectively connected to 2 water distribution bottles 6 through water pipes 102 and the top water inlet of 1 sample measurement bottle 16 through the sample measurement bottle water pipe 106; the waste water bottle is connected to the side water outlet of the sample measurement bottle 16 through the peristaltic pump water pipe 101 of the automatic cleaning system waste water peristaltic pump 1302 to achieve waste water recycling and treatment.

[0098] Figure 10 As shown in the figure, it is the structural diagram of the automatic water quality monitoring system. As shown in the figure, the monitoring probe 18 of the automatic water quality monitoring system is placed into the sample measurement bottle 16 through the top of the sample measurement bottle. The top water inlet is connected to the sample measurement bottle inlet pipe 106, and there is 1 water outlet on the side and 1 water inlet are both connected to the peristaltic pump water pipe 101.

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

[0100] The industrial control computer is a prior art and can control the operations of the above components through programming.

[0101] In use, first, the control system issues an instruction to start the submersible pump. The submersible pump sends the groundwater in the saturated zone to the sampling bottle of the water quality automatic monitoring system to start well flushing. If the water quality parameters reach stability for three consecutive times, the monitoring results start to be recorded. The automatic cleaning system starts to clean the sampling bottle well.

[0102] While the automatic collection system in the saturated zone 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, and then calculates the suction force with the maximum sampling efficiency according to the real-time water content and temperature. The controller turns on the vacuum pump of the vadose zone and soil automatic collection system to evacuate the space of the water distribution bottle and the sampling ceramic head to the specified negative pressure. Therefore, the groundwater in the unsaturated zone enters the water distribution bottle.

[0103] Step 04, the water quality automatic monitoring system conducts water quality detection; the water quality detection includes detecting the Voc index in the water, analyzing the heavy metal components and their contents, and detecting the microbial content, etc. The control system starts the peristaltic pump of the water quality automatic monitoring system to extract the water sample in the water distribution bottle into the sampling bottle to start monitoring and reading. These methods are existing technologies and will not be elaborated here.

[0104] Step 05, clean the water distribution bottle and the sampling bottle; then start the cleaning system for cleaning, and clean the water distribution bottle and the sampling bottle well at the same time. Cleaning the water distribution bottle and the sampling bottle is 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, if the water content probe of the control system monitors the change in the water content in the unsaturated zone, the above-mentioned links will be automatically started.

[0106] In summary, by designing an integrated device, the present invention installs a cross-media groundwater sampling system for soil, vadose zone, and saturated zone in a layered manner in a single borehole. With a set of monitoring equipment, the above-mentioned multi-layer cross-media groundwater sampling and monitoring can be completed, greatly saving costs and improving efficiency; realizing the full-automatic monitoring of the vertical distribution of groundwater pollutants, thus making the entire groundwater monitoring work more efficient, and improving the accuracy and reliability of water quality monitoring.

[0107] The present invention can timely detect leakage by real-time monitoring of the underground water content, and at the same time, sampling and monitoring play a warning role for pollution, so as to take timely measures to ensure that pollutants can be effectively prevented from further spreading to the 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 unsaturated groundwater and enhance the accuracy and reliability of monitoring.

[0108] At the same time, since the present invention adopts automatic monitoring, it can be deployed in the wild for a long time. Through continuous sampling and monitoring, real-time uploading and feedback of data are carried out, which is convenient for long-term continuous observation of cross-media groundwater.

[0109] The above are only embodiments of the present application, and do not thereby limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall similarly be included within the patent protection scope of the present application.

Claims

1. A soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring method, characterized in that: The soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring method comprises the following steps: Step 01, the control system is started, and water is pumped through the vacuum pump and the submersible pump; Step 02, the vacuum pump pumps water into the water distribution bottle through the sampling clay head; the water pumped by the submersible pump goes directly into the sample bottle of the water quality automatic monitoring system; Step 03, adjust the vacuum pump suction to ensure the maximum sampling efficiency during sampling, so that the monitoring results are accurate and reliable; The moisture content θ is described by the soil moisture characteristic curve as a function of the unsaturated zone matrix potential ψ: According to the above formula, the efficiency formula of pumping is obtained: For the unsaturated hydraulic conductivity K(θ), use the following formula: Since the viscosity of water decreases with increasing temperature, it directly affects the unsaturated hydraulic conductivity K(θ). Considering the adaptability of the equipment to temperature changes, K(θ) is expanded to K(θ,T): Where, θ: soil volume moisture content (m 3 / m 3 );θ s :Saturated moisture content (m 3 / m 3 );θ r :Residual moisture 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 (℃); The matrix potential with the maximum efficiency is thus obtained, and the suction force of the vacuum pump is adjusted according to the actual moisture content and temperature; Step 04, the water quality automatic monitoring system performs water quality testing; The control system starts the peristaltic pump of the automatic water quality monitoring system, extracts the water sample from the water distribution bottle into the test bottle and starts monitoring the readings; Step 05, clean the water dispensing bottle and the sample bottle; then start the cleaning system to clean, and clean the water dispensing bottle and the sample bottle at the same time.

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

3. A device for realizing the soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring method as claimed in claim 1, characterized in that: The device includes an automatic soil groundwater collection system arranged in a soil layer, an automatic groundwater collection system for an argon zone arranged in an argon zone, an automatic groundwater collection system for a saturated zone arranged in a saturated zone, an automatic cleaning system, an automatic water quality monitoring system and a control system; wherein the automatic soil groundwater collection system, the automatic groundwater collection system for an argon zone and the automatic groundwater collection system for a saturated zone are located in a borehole and are arranged in an upper and lower distribution, and the automatic soil groundwater collection system, the automatic groundwater collection system for an argon zone and the automatic groundwater collection system for a saturated zone are respectively connected to the automatic cleaning system and the automatic water quality monitoring system and control system; through the soil, argon zone and saturated zone groundwater sampling systems arranged in layers in a single borehole, they are linked with the shared automatic cleaning system and the automatic water quality monitoring system and control system to achieve cross-medium synchronous monitoring; The soil and groundwater automatic collection 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 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 the control system and the water quality automatic monitoring system; The automatic groundwater collection system of the vadose zone collects groundwater samples in the vadose zone and transmits them to the automatic water quality monitoring system; it 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 the control system and the automatic water quality monitoring system; The automatic groundwater collection system in the saturated zone collects groundwater samples in the saturated zone and transmits them to the automatic water quality monitoring system; it includes a water level meter and a submersible pump, both of which are connected to the control system; Automatic cleaning system, used for cleaning the water distribution bottles of the automatic groundwater collection system of the aeration zone and the automatic groundwater collection system of the soil; including pure water bottle, waste water bottle and peristaltic pump; the pure water bottle is connected to the electromagnetic valve controlled by the control system through the peristaltic pump, the sample bottle is also connected to the electromagnetic valve, and the waste water bottle is connected to the sample bottle through the peristaltic pump; The automatic water quality monitoring system realizes water quality monitoring through a monitoring probe, and includes a sample bottle, a peristaltic pump and a monitoring probe, wherein the monitoring probe is arranged in the sample bottle, and the monitoring sample is provided to the sample bottle through the peristaltic pump; The control system includes an industrial computer, a vacuum pump, an electromagnetic valve and control wires connecting various systems to control the operation of the above systems, perform data sampling and early warning; the control system dynamically adjusts the suction of the vacuum pump according to the real-time moisture content and temperature to control the sampling efficiency of unsaturated groundwater.

4. The soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device according to claim 3 is characterized in that: Automatic soil and groundwater collection system The automatic soil collection system includes a sampling clay head, a moisture content and temperature probe and a water distribution bottle, which enters the soil layer of the borehole through a PVC-U monitoring tube equipped with a sampling clay head, wherein 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 through the sampling clay head water pipe; the water distribution bottle air 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; 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.

5. The soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device according to claim 3 is characterized in that: The automatic groundwater collection system in the aeration zone includes a sampling clay head, a moisture content and temperature probe, and a water distribution bottle. The system enters the aeration zone of the borehole through a PVC-U monitoring tube equipped with the sampling clay head, wherein the sampling clay head is placed in the aeration zone, and the top of the sampling clay head is connected to the water inlet at the bottom of the water distribution bottle through the sampling clay head water pipe; the water distribution bottle air 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; 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.

6. The soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device according to claim 3 is characterized in that: The automatic groundwater collection system in the saturated zone is buried in the saturated layer through a PVC-U monitoring pipe with a filter. The automatic groundwater collection system in the saturated zone is arranged in a PVC-U slit pipe sleeved in 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, and the submersible pump is connected to the electromagnetic valve of the automatic water quality monitoring system through a water outlet pipe.

7. The soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device according to claim 6 is characterized in that: The filter is composed of a nylon screen and fine sand, wherein the nylon screen is arranged outside the PVC-U monitoring tube and attached to the PVC-U slit tube, and the fine sand is arranged inside the PVC-U monitoring tube and located outside the PVC-U slit tube.

8. The soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device according to claim 3 is characterized in that: The automatic cleaning system is used to clean the water distribution bottles of the automatic groundwater collection system in the aeration zone and the automatic groundwater collection system in the soil; it includes a pure water bottle, a waste water bottle, and a peristaltic pump; wherein the peristaltic pump is further 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 an electromagnetic valve controlled by a control system through the automatic cleaning system pure water peristaltic pump, and is controlled by the control system, and the electromagnetic valve is 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.

9. The soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device according to claim 3 is characterized in that: The automatic water quality monitoring system realizes water quality monitoring through a monitoring probe, and includes a sample bottle, a peristaltic pump of the automatic water quality monitoring system and a monitoring probe, wherein the monitoring probe extends into the sample bottle, and the sample bottle inputs the sample to be tested through the peristaltic pump of the automatic water quality monitoring system.

10. The soil-vadose zone-saturated zone cross-medium groundwater automatic monitoring device according to claim 9 is characterized in that: In the automatic water quality monitoring system, the monitoring probes include any one or any combination of water temperature, pH, conductivity, turbidity, dissolved oxygen, redox potential and characteristic pollutant monitoring probes.

Images