Method for determining injection area by detecting hydraulic permeability coefficient and drill bit

Abstract

The invention belongs to the technical field of environmental restoration, and particularly relates to a medicament injection area determination method. A permeability detection module is integrated on a detection drill bit, the relative permeability coefficient is obtained by measuring the pressure formed by pumping water into soil at different depths at a constant flow rate, the soil infiltration capacity is reflected, the relative permeability coefficient and the pollutant distribution concentration are comprehensively considered, the K-Means algorithm is used for clustering, the pollution characteristics of the K-type pollutant site are divided out, and the soil infiltration capacity is calculated according to the K-type pollutant site pollution characteristics. And a kind of characteristics with high pollutant concentration and good permeability are selected to obtain depth coordinates, so that scientific and accurate position reference is provided for injection repair or blocking of medicaments, and pollutant diffusion is restrained as soon as possible.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental restoration, and in particular relates to a method for detecting a hydraulic permeability coefficient to determine an injection area and a drill bit. Background Art

[0002] The pollution of sudden accidents and industrial agglomeration sites is distributed in a point-like manner. The most critical thing for the disposal of such polluted sites is to be efficient and fast to prevent the spread of pollutants. However, the traditional method of determining the injection area is often based on experience or rough soil pollution analysis, lacking scientificity and accuracy, and the remediation process is extensive. The hydraulic permeability coefficient refers to the unit flow rate under unit hydraulic gradient in an isotropic medium, indicating the difficulty of fluid passing through the pores. It is an indicator that comprehensively reflects the permeability of the soil. It is usually determined by test methods, including laboratory measurement methods and field measurement methods or empirical estimation methods. Summary of the invention

[0003] In order to solve the above technical problems, the first aspect of the present invention provides a detection drill bit for detecting the hydraulic permeability coefficient and determining the injection area. The detection drill bit includes a pollutant detection module and a permeability detection module. The permeability detection module includes a water injection port and a pressure sensor for measuring the water injection pressure; the water injection port is connected to a water pump through a water pipe; a flow sensor is provided on the water pipe; the pressure sensor measures the water injection pressure, which is used to reflect the difficulty of injecting water into the soil.

[0004] In an optional embodiment, a pressure sensor is installed on the water pipe to measure the water injection pressure in the horizontal direction of the soil.

[0005] In an optional embodiment, a pressure sensor is installed directly below the water injection port to measure the water injection pressure in the vertical direction of the soil.

[0006] In an optional embodiment, the contaminant detection module includes a laser induced fluorescence component and a membrane interface component.

[0007] A second aspect of the present invention provides a method for detecting a hydraulic permeability coefficient and determining an injection area, which is applied to detecting a drill bit, wherein the drill bit detection module includes a contaminant detection module and a permeability detection module, and the method includes the following steps:

[0008] Step 1: Push the detection drill bit into the soil at a speed of 2 cm / s for a depth of H meters. At the same time, the pollutant detection module obtains the pollution value C(h) at the depth h; the permeability detection module pumps water into the soil through the water injection port at a constant flow rate Q, and the pressure sensor measures the water injection pressure P at the depth h. m (h);

[0009] Step 2: Place P m (h) Bring in P * (h) = Pm (h)-P atm -P h The corrected pressure P is obtained from * (h), where P atm is the local atmospheric pressure, P h is the hydrostatic pressure;

[0010] Step 3: Let the relative permeability

[0011] Step 4: Perform exponential weighted average smoothing on the relative permeability A(h) to obtain A * (h);

[0012] Step 5: Contamination value C(h) and relative permeability A * (h) After normalization, the normalized pollution value C'(h) and the normalized relative permeability A'(h) are obtained;

[0013] Step 6: Select the number of clusters K, K ≥ 3, and use the K-Means algorithm to cluster the data set D = [A'(h), C'(h)] to obtain K cluster center coordinates and K clusters;

[0014] Step 7: Draw the clustering results and analyze them. Arrange the cluster center coordinates in descending order and select the first three cluster center coordinates. The cluster divided by the cluster center coordinate with the highest contamination value is the desired cluster.

[0015] Step 8: Obtain the depth h = {h1, h2, ...} corresponding to the data in the required cluster as the estimated optimal injection position.

[0016] The beneficial effects of the embodiments of the present application are: a permeability detection module is integrated on the detection drill bit, the soil permeability is comprehensively reflected by the relative permeability coefficient, the permeability coefficient is combined with the pollutant distribution concentration for consideration, and the K-Means algorithm is used for clustering to divide the pollution characteristics of the K-type pollutant site, from which a type of characteristics with high pollutant concentration and good permeability is selected to obtain depth information, providing a scientific and accurate position reference for injection repair or barrier agents. For example, an injection drill rod with a packer can be used for layered and refined injection. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The invention and further preferred embodiments are explained in more detail below with reference to an exemplary embodiment schematically shown in the drawing, without the invention being restricted to the exemplary embodiment shown.

[0018] Figure 1 It is a schematic diagram of a permeability detection module for detecting a drill bit in an embodiment of the present invention.

[0019] Figure 2 Schematic diagram of a contaminant detection module for detecting a drill bit in an embodiment of the present invention.

[0020] Figure 3 It is a working principle diagram of a permeability detection module for detecting a drill bit in an embodiment of the present invention.

[0021] The reference numerals shown in the figure are: 101, water pipe; 102, water inlet; 103, first pressure sensor; 104, second pressure sensor; 105, flow sensor; 106, water pump; 107, water source; 2, laser induced fluorescence component; 3, membrane interface component; 4, conductivity sensor. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0024] The present invention will be described in detail below by way of describing exemplary embodiments.

[0025] See also Figure 1-3 In the embodiment, the permeability detection module of the detection drill bit is provided with a water injection port 102 on the detection drill bit, and the water injection port 102 is connected to a water pump 106 through a water pipe 101, and the water pump is connected to a water source 107. A second pressure sensor 104 and a flow sensor 105 are provided on the water pipe 101. The second pressure sensor 104 is used to reflect the difficulty of horizontally injecting water into the soil. The first pressure sensor 103 is installed directly below the water injection port 102 to reflect the difficulty of water penetration in the vertical direction. The pollutant detection module includes a laser induced fluorescence component 2, a membrane interface component 3 and a conductivity sensor 4.

[0026] The soil permeability coefficient is usually determined by experimental methods, including laboratory measurements and field measurements or empirical estimation methods. Laboratory measurements and field measurements often take several days, and field measurements such as borehole water pressure tests may cause soil damage and are not suitable for measurements at contaminated sites. In addition, the data are over a large range and are not sensitive enough to changes in soil permeability levels.

[0027] Traditional methods for determining injection areas are often based on experience or selecting injection points according to pollution concentration to establish injection wells. The process of placing reagents in injection wells is rough, and the variation range of the permeability coefficient of the 3m screen pipe can often reach multiple orders of magnitude. In addition, 90% or more of the total volume of the reagents can easily be pushed into the high-permeability formation medium near the screen pipe layer section with less than 10%, resulting in problems such as reagent waste and poor repair effect.

[0028] The method for determining a drug injection area comprises the following steps:

[0029] Step 1: Push the detection drill bit into the soil at a speed of 2 cm / s for a depth of H meters. At the same time, the pollutant detection module obtains the pollution value C(h) at the depth h; the permeability detection module pumps water into the soil through the water injection port at a constant flow rate Q, and the pressure sensor measures the water injection pressure P at the depth h. m (h);

[0030] Step 2: Place P m (h) Bring in P * (h) = P m (h)-P atm -P h The corrected pressure P is obtained from * (h), where P atm is the local atmospheric pressure, P h is the hydrostatic pressure.

[0031] Step 3: Let the relative permeability

[0032] Step 4: Perform exponential weighted average smoothing on A(h) to obtain the smoothed relative permeability A * (h);

[0033] Since the injection pressure is sensitive to the shape, size, non-uniformity coefficient and viscosity of soil particles, the A(h) data graph will be sharp. In order to make the result more accurate, the curve needs to be smoothed. The exponential weighted average smoothing formula is as follows:

[0034] A h (h) = β × A h-1 (h)+(1-β)×θ(h)

[0035] where θ(h) is the actual value of the hth meter, Ah-1 (h) is the exponentially weighted average of the hth meter, and β is A h-1 The weight of (h) is an adjustable hyperparameter (0<β<1).

[0036] Step 5: Contamination value C(h) and smoothed relative permeability A * (h) After normalization, the normalized pollution value C'(h) and the normalized relative permeability A'(h) are obtained;

[0037] Normalization is to map the permeability A'(h) and pollution value C'(h) data to the range of 0-1, and convert the dimensional expression into a dimensionless expression to facilitate the comparison of indicators of different units or magnitudes. The normalization formula is as follows:

[0038]

[0039] By using the maximum and minimum values ​​(or maximum values) of the variables to convert the original data into data within a specific range, the original data can be scaled proportionally, thereby eliminating the impact of dimension and order of magnitude and changing the weight of the variable in the analysis to solve the problem of different measurements.

[0040] Step 6: Select the number of clusters K, K ≥ 3, and use the K-Means algorithm to cluster the set [A'(h), C'(h)] to obtain K cluster center coordinates and K clusters;

[0041] Step 7: Draw the clustering results and analyze them. Arrange the cluster center coordinates in descending order and select the first three cluster center coordinates. The cluster divided by the cluster center coordinate with the highest contamination value is the desired cluster.

[0042] Step 8: Obtain the depth h = {h1, h2, ...} corresponding to the data in the required cluster as the estimated optimal injection position.

[0043] According to the optimal injection depth, an injection drill rod with a packer can be used to perform layered and refined in-situ injection.

Claims

1. A method for detecting hydraulic permeability coefficient and determining injection area, characterized in that: Applied to detecting a drill bit, the detecting drill bit includes a contaminant detection module and a permeability detection module, and the method includes the following steps: Step 1: Push the detection drill into the soil at a constant speed for H meters. At the same time, the pollutant detection module obtains the pollution value C(h) at the depth h; the permeability detection module pumps water into the soil through the water injection port at a constant flow rate Q, and the pressure sensor measures the water injection pressure P at the depth h. m (h); Step 2: Place P m (h) Bring in P * (h) = P m (h)-P atm -P h The corrected pressure P is obtained from * (h), where P atm is the local atmospheric pressure, P h is the hydrostatic pressure; Step 3: Let the relative permeability Step 4: Perform exponential weighted average smoothing on the relative permeability A(h) to obtain A * (h); Step 5: Contamination value C(h) and relative permeability A * (h) After normalization, the normalized pollution value C'(h) and the normalized relative permeability A'(h) are obtained; Step 6: Select the number of clusters K, K ≥ 3, and use the K-Means algorithm to cluster the data set D = [A'(h), C'(h)] to obtain K cluster center coordinates and K clusters; Step 7: Draw the clustering results and analyze them.

2. A method for detecting hydraulic permeability coefficient and determining injection area according to claim 1, characterized in that: The step 7 of drawing the clustering results and analyzing them specifically includes: Step 701: Arrange the cluster center coordinates in descending order, select the first three cluster center coordinates, and the cluster divided by the cluster center coordinate with the highest pollution value is the desired cluster; Step 702: Obtain the depth h={h1, h2, ...} corresponding to the data in the desired cluster as the estimated optimal injection position.

3. The method for determining the injection area by detecting the hydraulic permeability coefficient according to claim 1, characterized in that: The speed at which the detection drill bit is pushed into the soil at a uniform speed is 2 cm per second.

4. A detection drill bit for detecting hydraulic permeability coefficient and determining injection area, characterized in that: A method for detecting the hydraulic permeability coefficient and determining the injection area as described in any one of claims 1 to 3 is applicable, wherein the detection drill bit integrates a pollutant detection module and a permeability detection module; the permeability detection module includes the water injection port and a pressure sensor for measuring the water injection pressure; the water injection port is connected to a water pump through a water pipe; and a flow sensor is provided on the water pipe.

5. A detection drill bit for detecting hydraulic permeability coefficient and determining injection area according to claim 4, characterized in that: The pressure sensor is installed on the water pipe to measure the water injection pressure P in the horizontal direction of the soil. m (h).

6. A detection drill bit for detecting hydraulic permeability coefficient and determining injection area according to claim 4, characterized in that: The pressure sensor is installed directly below the water injection port to measure the water injection pressure P in the vertical direction of the soil. m (h).

7. A detection drill bit for detecting hydraulic permeability coefficient and determining injection area according to claim 4, characterized in that: The pollutant detection module includes a laser induced fluorescence component and a membrane interface component.

Images