A well coupling electric field precision positioning method for thick heap landfill leakage

Abstract

The present application relates to landfill leakage positioning technical field, specifically to a kind of well coupling electric field accurate positioning method for thick stack landfill leakage.In landfill, multiple well sites are set to drill, obtaining multiple drillings;Direct current electric field is applied to the top and bottom of landfill, and the voltage of each drilling is measured;According to the voltage of each drilling, a distribution curve is established, and a certain number of minimum points in the distribution curve are obtained in turn;According to the drillings corresponding to the set number of minimum points, a polygon is fitted, the center of gravity of the fitted polygon is obtained, and the leakage point of the landfill is obtained.The detection method proposed in the present application can adapt to landfills of different thickness and different structure, especially suitable for leakage detection of thick stack landfill, and can effectively penetrate thick layer of landfill and accurately locate the damage of underground impermeable layer.

Description

TECHNICAL FIELD

[0001] The present application relates to landfill leakage positioning technology field, and particularly relates to a kind of well coupling electric field accurate positioning method for thick heap body landfill leakage. BACKGROUND

[0002] With the acceleration of urbanization, landfill becomes the main way of solid waste disposal, over time, the impermeable layer at the bottom of landfill can be damaged due to external factors or expiration of service life, resulting in harmful substances leakage, polluting the surrounding soil and groundwater;Therefore, how to quickly and accurately locate the leakage position becomes an important issue in environmental protection and management.

[0003] The existing landfill leakage detection technology mainly relies on surface monitoring or using surface electrical measurement in electrical prospecting, these methods have certain effect in shallow or thin heap body, but when facing landfill with large thickness of heap body, electric signal is often shielded by thick layer of landfill, and cannot accurately penetrate to the impermeable layer, resulting in poor positioning effect, low detection accuracy and efficiency of leakage position. SUMMARY

[0004] In order to solve the problems in the prior art, the present application provides a kind of well coupling electric field accurate positioning method for thick heap body landfill leakage. The scheme includes: setting multiple well sites in landfill for drilling, obtaining multiple drillings;A direct current electric field is applied to the top and bottom of the landfill, and the voltage of each drilling is measured respectively;According to the voltage of each drilling, a distribution curve is established, and a plurality of minimum points in the distribution curve are obtained in turn;According to the drilling corresponding to the plurality of minimum points, a polygon is fitted, the center of gravity of the fitted polygon is obtained, and the leakage point of the landfill is obtained. The detection method proposed in the present application can adapt to landfill with different thickness and different structure, especially suitable for leakage detection of thick heap body landfill, which can effectively penetrate thick layer of landfill and accurately locate the damage of underground impermeable layer.

[0005] The present application adopts the following technical scheme, a kind of well coupling electric field accurate positioning method for thick heap body landfill leakage, comprising:

[0006] Multiple well sites are set in landfill for drilling, obtaining multiple drillings;

[0007] A direct current electric field is applied to the top and bottom of the landfill, and the voltage of each drilling is measured respectively;

[0008] According to the voltage of each drilling, a distribution curve is established, and a plurality of minimum points in the distribution curve are obtained in turn;

[0009] According to the minimum point corresponding to the fitting polygon of the drilling well, the gravity center of the fitting polygon is obtained, and the leakage point of the landfill is obtained.

[0010] Further, the drilling depth exceeds the garbage pile body, and does not exceed the anti-seepage layer.

[0011] Further, the direct current electric field is applied to the top and bottom of the landfill, specifically, a plurality of electrodes are uniformly arranged on the top of the landfill to provide a positive voltage, and the bottom of the landfill is grounded.

[0012] Further, the measuring electrode and the electric field measuring device are arranged in the drilling well, for measuring the voltage and the vertical electric field component corresponding to each drilling well.

[0013] The beneficial effects of the present application are: the present application provides a well-coupled electric field precise positioning method for thick pile landfill leakage, which is suitable for landfills of different thicknesses and different structures, especially suitable for thick pile landfill leakage detection, can effectively penetrate thick landfill, and accurately position the damage of the underground anti-seepage layer, can effectively locate the leakage point in the thick pile landfill, has the characteristics of high positioning accuracy, wide detection range and strong adaptability, through coupling electric field measurement and analysis, the thick pile landfill leakage point can be accurately positioned, the positioning error is small, and the real-time electric field measurement can find the leakage problem in the early stage, reducing the risk of environmental pollution. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0015] Figure 1 A well-coupled electric field precise positioning method for thick pile landfill leakage of the present application is shown in the flowchart.

[0016] Figure 2 A well-coupled electric field precise positioning method for thick pile landfill leakage of the present application is shown in the flowchart.

[0017] Figure 3 A well-coupled electric field precise positioning method for thick pile landfill leakage of the present application is shown in the flowchart.

[0018] Figure 4 A well-coupled electric field precise positioning method for thick pile landfill leakage of the present application is shown in the flowchart.

[0019] Figure 5This is a simulation result diagram of precise positioning of coupled electric fields in a well for leakage in a thick landfill according to an embodiment of the present invention;

[0020] In the figure: 1. Drilling; 2. DC power supply; 3. Electric field measurement device; 4. Measuring electrode. DETAILED DESCRIPTION

[0021] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0022] A flow chart of a method for accurately locating leakage in a thick landfill using a coupled electric field in a well according to an embodiment of the present invention is shown in FIG. Figure 1 Shown, including:

[0023] Setting multiple well locations in the landfill for drilling to obtain multiple drilled wells;

[0024] A DC electric field was applied to the top and bottom of the landfill and the voltage was measured at each borehole;

[0025] In the embodiment of the present invention, measuring electrodes and an electric field measuring device are provided in the wellbore to measure the voltage and vertical electric field component corresponding to each wellbore.

[0026] Establish a distribution curve based on the voltage of each well, and obtain a set number of minimum value points in the distribution curve in order from small to large;

[0027] According to the drilling fitting polygons corresponding to the set number of minimum value points, the center of gravity of the fitting polygons is obtained to obtain the leakage points of the landfill.

[0028] In another embodiment of the present invention:

[0029] like Figure 2 As shown, in an embodiment of the present invention, several boreholes 1 are arranged in a landfill, and the boreholes penetrate deep into the landfill layer until the impermeable layer. At the same time, measuring electrodes are installed in the boreholes, and the electric field measuring device 3 measures the electric field and vertical electric field component of each borehole through the electrodes in the boreholes. At the same time, the present invention evenly lays multiple DC power supplies 2 on the surface of the boreholes, and grounds the impermeable layer of the landfill, thereby forming a DC electric field.

[0030] In the embodiment of the present invention, the arranged drilled wells may also be exhaust holes existing in the landfill. Directly using the exhaust holes for measurement can further improve the positioning efficiency.

[0031] In the embodiment of the present application, the electric field measuring device can be an electric field measuring instrument, or an electric field sensor or any device capable of receiving electric signals.

[0032] In the embodiment of the present application, the drilling wells arranged in the landfill site have a consistent depth.

[0033] In the embodiment of the present application, the direct current electric field is applied to the top and bottom of the landfill, the voltage distribution and the vertical electric field component are measured in the drilling wells, the change of the electric field in the vertical direction is analyzed, in the area without leakage, the electric field distribution is relatively uniform, while in the leakage area, the electric field is affected by the outflow of the leakage liquid and forms a loop with the outside, which affects the change of the electric field distribution, resulting in a relatively reduced voltage amplitude; thus, by arranging multiple drilling wells in the landfill site, the voltage values and the vertical electric field components at different depths in the wells and the voltage values and the vertical electric field components of different well combinations are measured and recorded, then by analyzing the voltage change of the electric field in different drilling wells, the minimum value of the voltage is found, in one specific embodiment of the present application, taking a polygon as an example, the first minimum value, the second minimum value and the third minimum value in the distribution curve are obtained; according to the triangle center formed by the drilling wells corresponding to the first minimum value, the second minimum value and the third minimum value, the position of the center of gravity is the predicted leakage point.

[0034] In the embodiment of the present application, the first minimum value, the second minimum value and the third minimum value are the minimum value, the second minimum value and the third minimum value obtained in turn by analyzing the distribution curve, and the triangle for judging the leakage point can be obtained by circumscribing these extreme value points.

[0035] In summary, by arranging multiple drilling wells inside the landfill site and deep into the landfill and the impermeable layer, the present application solves the problem that the electric field is difficult to penetrate the thick stack. The layout optimization of the drilling well arrangement improves the detection range and accuracy; unlike the traditional surface electric measurement method, the present application uses the coupling electric field technology, that is, by applying an electric field to the bottom of the landfill and the surrounding rock outside the stack through the drilling wells, the electric signal of the leakage area is enhanced, then the voltage distribution and the vertical electric field component are measured by the coupling electric field in the drilling wells, and the change of the voltage and the vertical electric field component is further analyzed, which ensures the effective conduction of the electric field method in the thick stack, improves the detection depth and accuracy, and at the same time, the laying of the direct current power supply can realize real-time electric field measurement of the landfill site, which can detect the leakage problem at an early stage and reduce the risk of environmental pollution.

[0036] In one experimental embodiment of the present application, as shown in Figure 3 the present application takes this model as an example to analyze the simulation experiment of the leakage of the thick stack landfill, first establishes the landfill model and sets the leakage point, sets the exhaust hole or drill hole at different positions from the leakage point, and analyzes the distribution of the coupling electric field at different depths and areas after applying a direct current electric field to the top of the landfill. Figure 4The simulation result shown is the change of the potential in different wells with depth, and analysis shows that when far from the leakage point, the change of the potential value with depth is relatively stable; and when close to the leakage point, the potential value decreases significantly; Figure 5 The simulation result shown is the change of the Z-direction electric field component in different wells with depth, and analysis shows that the closer to the leakage point, the more intense the change of the Z-direction electric field component with depth, the model reflects the difference of the electric field distribution at different positions from the leakage point, especially near the leakage point, the electric field distribution presents a significant change characteristic, and this change trend provides an important basis for identifying the leakage position.

[0037] The above merely describes preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for accurately locating leakage in thick landfills using a coupled electric field in a well, characterized by: The application relates to a method for detecting a leakage point of a landfill. A plurality of well sites are arranged in a landfill to drill a plurality of drill holes; the drill holes have a depth exceeding a garbage pile to reach a seepage prevention layer and not exceeding the seepage prevention layer; A direct current electric field is applied to the top and bottom of the landfill, and a voltage and a vertical electric field component corresponding to each drill hole are measured through a measuring electrode arranged in the drill hole and an electric field measuring device; A distribution curve is established according to the voltage of each drill hole, and a plurality of minimum value points in the distribution curve are sequentially obtained from small to large; A polygon is fitted according to the drill holes corresponding to the plurality of minimum value points, a gravity center of the fitted polygon is obtained, and a leakage point of the landfill is obtained.

2. The method of claim 1, wherein the method is used for accurately positioning a well for coupling an electric field to a thick landfill leak. The direct current electric field applied to the top and bottom of the landfill is specifically as follows: a plurality of electrodes are uniformly arranged on the top of the landfill to provide a positive voltage, and the bottom of the landfill is grounded.

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