Coal mine goaf extraction drill hole extraction negative pressure optimization method

Abstract

The invention discloses a coal mine goaf extraction drill hole extraction negative pressure optimization method, and relates to the technical field of coal mine gas extraction negative pressure optimization. According to the extraction negative pressure optimization method for the extraction drill hole in the coal mine goaf, when gas extraction is carried out on the coal mine goaf, division processing is carried out, a plurality of extraction areas are obtained, roof image data of the corresponding areas are obtained, identification analysis is carried out, and a plurality of permeation areas are obtained; extracting data and geological environment data of a plurality of extracting drill holes of a plurality of extracting wells in each permeation area are obtained, data analysis is carried out respectively, a comprehensive extracting negative pressure index and a geological extracting correction index of each extracting drill hole are obtained, comprehensive analysis is carried out, a comprehensive extracting negative pressure correction index of each permeation area is obtained, and a geological extracting negative pressure correction index of each permeation area is obtained; according to the method, corresponding optimization measures are taken based on the comprehensive extraction negative pressure correction index of each permeation area, so that the gas extraction efficiency is improved, and the accuracy and efficiency of the extraction process are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of optimizing the negative pressure of coal mine gas drainage, and specifically to a method for optimizing the negative pressure of gas drainage from drainage boreholes in the goaf of a coal mine. Background Art

[0002] The goaf of a coal mine refers to the underground cavity area caused by mining operations during coal mining. These cavities are usually formed by the mining of coal seams or other ore layers. The air flow in the goaf is not smooth, and harmful gases such as gas are likely to accumulate, thus triggering safety accidents such as fires and explosions. The drainage borehole technology is widely used to drain harmful gases such as gas and regulate the gas environment in the goaf. A drainage borehole refers to drilling through a coal seam or rock formation in the goaf area through drilling technology to establish a gas drainage channel leading to the goaf. Through this channel, the harmful gases accumulated in the goaf can be effectively extracted, the gas pressure can be reduced, the gas concentration in the mine can be decreased, and the safety of the mine can be improved.

[0003] The prior art, such as a gas drainage method for slicing mining of extra-thick coal seams disclosed in a patent application with the publication number of CN110486079B, belongs to the technical field of coal mine gas drainage and control. The gob-side entry retaining is carried out by using the return airway of the last slicing working face in the adjacent upper mining section of the section to be mined, and a high-negative-pressure drainage pipeline and a low-negative-pressure drainage pipeline are laid; the bedding boreholes are constructed and sealed, and are connected to the high-negative-pressure drainage pipeline, and the pre-drainage of gas before coal mining and the drainage of pressure-relief gas during coal mining are carried out by using the bedding boreholes; the large-diameter boreholes shared by multiple slices are constructed and the holes are protected by casings, and are connected to the low-negative-pressure drainage pipeline for gob gas drainage. The large-diameter boreholes shared by multiple slices are used as nitrogen injection boreholes to inject nitrogen into the gob for fire prevention and extinguishing in the gob. This method realizes multiple uses of one roadway, replacing a roadway with a borehole, and multiple uses of one borehole, reduces the construction workload of gas control, improves the gas drainage effect of slicing mining of extra-thick coal seams, achieves effective control of gas outburst in slicing mining of extra-thick coal seams, and has remarkable economic benefits.

[0004] Based on the above scheme, it is found that the limitations of the prior art at least include the following problems. It is difficult for the prior art to be adjusted according to the actual geological conditions and drainage effects, which easily leads to unsatisfactory drainage effects in some areas, and it is difficult to effectively reduce the gas concentration, and thus it is difficult to reduce potential safety hazards. Secondly, the prior art does not fully consider the permeability difference during the drainage process and lacks precise control and optimization of the drainage negative pressure, which easily leads to instability in the gas drainage process, and it is difficult to precisely adjust the drainage negative pressure of each layer, thereby increasing the risk and difficulty of gob gas drainage, and reducing the overall efficiency and safety of gas drainage. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the present invention provides an optimization method for the extraction negative pressure of gas extraction boreholes in coal mine goafs, which solves the problems that it is difficult for the prior art to adjust according to actual geological conditions and extraction effects, and that the differences in permeability are not fully considered and the precise control and optimization of the extraction negative pressure are lacking.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: An optimization method for the extraction negative pressure of gas extraction boreholes in coal mine goafs includes the following steps: When extracting gas from a coal mine goaf, perform regional division processing to obtain several extraction regions of the coal mine goaf to be optimized, and obtain the roof image data of the corresponding regions, perform identification and analysis to obtain several permeability regions of the coal mine goaf to be optimized; and obtain the extraction data and geological environment data of several extraction boreholes of several extraction wells in each permeability region of the coal mine goaf to be optimized, and perform data analysis respectively to obtain the comprehensive extraction negative pressure index and geological extraction correction index of each extraction borehole of each extraction well in each permeability region of the coal mine goaf to be optimized, and perform comprehensive analysis to obtain the comprehensive extraction negative pressure correction index of each permeability region of the coal mine goaf to be optimized; and take corresponding optimization measures based on the comprehensive extraction negative pressure correction index of each permeability region of the coal mine goaf to be optimized.

[0007] Further, the roof image data is specifically the pixel value and two-dimensional coordinates of each roof pixel point, the extraction data includes the extraction volume value, borehole depth value, borehole cross-sectional area value, temperature value, gas concentration value, pressure gradient index, gas viscosity value, borehole length value, and the geological environment data includes porosity value, stress index, adsorption value, and the inclination angle value, aperture value, and extension depth value of each crack.

[0008] Further, the specific steps for obtaining several permeable regions of the goaf to be optimized in a coal mine are as follows: Edge detection is performed on the pixel values of each roof pixel point in each extraction area of the goaf to be optimized, and several crack edge pixel points in the roof image of each extraction area of the goaf to be optimized are obtained; and connectivity processing is performed on each crack edge pixel point in the roof image of each extraction area of the goaf to be optimized, and several roof crack regions in each extraction area of the goaf to be optimized are obtained; and comprehensive analysis is performed on the two-dimensional coordinates of each crack edge pixel point in each roof crack region of each extraction area of the goaf to be optimized to obtain the perimeter value and area value of each roof crack region in each extraction area of the goaf to be optimized, and comprehensive analysis is performed to obtain the morphological index of each roof crack region in each extraction area of the goaf to be optimized; the pixel values of each roof pixel point in each roof crack region of each extraction area of the goaf to be optimized are processed by standard deviation to obtain the texture index of each roof crack region in each extraction area of the goaf to be optimized, and comprehensive analysis is performed in combination with the morphological index to obtain the permeability characteristic index of each extraction area of the goaf to be optimized, and judgment analysis is performed with a preset permeability characteristic index threshold interval to obtain several permeable regions of the goaf to be optimized.

[0009] Further, the specific formulas for calculating the morphological index and permeability characteristic index of each roof crack region in each extraction area of the goaf to be optimized are as follows: Among them, XtZ ij is the morphological index of the j-th roof crack region in the i-th extraction area of the goaf to be optimized, ZcL ij , ZaL ij are the perimeter value and area value of the j-th roof crack region in the i-th extraction area of the goaf to be optimized in sequence, ω is the adjustment coefficient stored in the database, π is the pi, WqS i is the permeability characteristic index of the i-th extraction area of the goaf to be optimized, WzS ij is the texture index of the j-th roof crack region in the i-th extraction area of the goaf to be optimized, α 1 , α 2 , η are the morphological coefficient, texture coefficient, and interaction coefficient stored in the database in sequence, α 1 +α 2 =1, i = 1, 2, 3,..., i 0 , i 0 is the number of extraction areas, j = 1, 2, 3,..., j 0 , j 0 is the number of roof crack regions.

[0010] Further, the specific steps to obtain the comprehensive drainage negative pressure index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized are as follows: Obtain the well depth value of each drainage well and the temperature reference value of each drainage borehole in each permeable area of the coal mine goaf to be optimized, and conduct a comprehensive analysis in combination with the drainage volume value, temperature value, borehole depth value, and borehole cross-sectional area value to obtain the initial drainage negative pressure index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized; and conduct a comprehensive analysis of the gas concentration value, pressure gradient index, gas viscosity value, and borehole length value of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized to obtain the drainage efficiency index and gas flowability index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized; and standardize the initial drainage negative pressure index, drainage efficiency index, and gas flowability index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized; and conduct a comprehensive analysis based on the initial drainage negative pressure index, drainage efficiency index, and gas flowability index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized after standardization to obtain the comprehensive drainage negative pressure index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized.

[0011] Further, the specific steps to obtain the drainage efficiency index and gas flowability index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized are as follows: Read the drainage volume value of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized, and obtain the borehole volume value; conduct a comprehensive analysis of the drainage volume value and borehole volume value of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized to obtain the drainage efficiency index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized; obtain the permeability value, humidity value, and humidity reference value of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized, and conduct a comprehensive analysis in combination with the pressure gradient index, gas viscosity value, and borehole length value to obtain the gas flowability index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized.

[0012] Further, the specific formulas for calculating the initial drainage negative pressure index and comprehensive drainage negative pressure index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized are as follows: Among them, CyF ghb is the initial drainage negative pressure index of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the coal mine goaf to be optimized, LcZ ghb , DzP ghb , WdZ ghb , CwD ghb, ZKS ghb , SdZ gh are the extraction volume value, borehole cross-sectional area value, temperature value, temperature reference value, borehole depth value, and well depth value of the bth extraction borehole of the hth extraction well in the gth permeable area of ​​the coal mine goaf to be optimized, respectively. χ is the gas constant stored in the database, and FyZ ghb is the comprehensive negative pressure index of the bth extraction borehole of the hth extraction well in the gth permeable area of ​​the coal mine goaf to be optimized, CyF′ ghb , LtX′ ghb , XcL′ ghb They are the initial negative pressure index, extraction efficiency index, and gas flowability index of the bth extraction borehole of the hth extraction well in the gth permeable area of ​​the coal mine goaf to be optimized after standardized processing, β 1 , β 2 , β 3 They are the initial coefficient, extraction efficiency coefficient, gas flow coefficient, and β stored in the database. 1 +β 2 +β 3 =1,g=1,2,3,…,g 0 , g 0 is the number of penetration areas, h = 1, 2, 3, ..., h 0 ,h 0 is the number of extraction wells, b=1, 2, 3, ..., b 0 , b 0 is the number of extraction boreholes, and e is a natural constant.

[0013] Further, the specific steps for obtaining the geological drainage correction index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized are as follows: Obtain the stress reference index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized, and perform normalization processing in combination with the porosity value, stress index, and adsorption value; and comprehensively analyze the porosity value, stress index, adsorption value, and stress reference index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized after normalization processing to obtain the geological drainage rate correction index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized; Obtain the inclination angle reference value, aperture reference value, and extension depth reference value of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized, and comprehensively analyze them in combination with the inclination angle value, aperture value, and extension depth value of each fracture to obtain the geological fluidity correction index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized; and comprehensively analyze the geological drainage rate correction index and geological fluidity correction index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized to obtain the geological drainage correction index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized.

[0014] Further, the specific formula for calculating the comprehensive drainage negative pressure correction index of each permeable area of the coal mine goaf to be optimized is as follows: Where, ZxF g is the comprehensive drainage negative pressure correction index of the g-th permeable area of the coal mine goaf to be optimized, Fy ghb , DzF ghb are the comprehensive drainage negative pressure index and geological drainage correction index of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the coal mine goaf to be optimized in sequence, ε 1 , ε 2 are the comprehensive drainage negative pressure coefficient and geological correction coefficient stored in the database in sequence, ε 1 +ε 2 =1, g = 1, 2, 3,..., g 0 , g 0 is the number of permeable areas, h = 1, 2, 3,..., h 0 , h 0 is the number of drainage wells, b = 1, 2, 3,..., b 0 , b 0 is the number of drainage boreholes, and e is the natural constant.

[0015] Further, the specific steps of taking corresponding optimization measures based on the comprehensive extraction negative pressure correction index of each permeable area in the goaf of the coal mine to be optimized are as follows: Compare and analyze the comprehensive extraction negative pressure correction index of each permeable area in the goaf of the coal mine to be optimized with the preset comprehensive extraction negative pressure correction index threshold respectively; If the comprehensive extraction negative pressure correction index of each permeable area in the goaf of the coal mine to be optimized is lower than or equal to the preset comprehensive extraction negative pressure correction index threshold, take the first extraction negative pressure optimization measure; If the comprehensive extraction negative pressure correction index of each permeable area in the goaf of the coal mine to be optimized is higher than the preset comprehensive extraction negative pressure correction index threshold, take the second extraction negative pressure optimization measure.

[0016] The present invention has the following beneficial effects:

[0017] (1) The extraction negative pressure optimization method for the goaf of the coal mine can, by identifying the permeable areas in the goaf of the coal mine, implement customized optimization measures for each extraction area, and through the comprehensive analysis of the geological environment and the negative pressure index, effectively improve the efficiency of gas extraction, avoid gas leakage and accumulation caused by insufficient negative pressure or over-extraction, thus ensuring the production safety of the mine, reducing the accident risk, and enhancing the safety and extraction efficiency of the mine.

[0018] (2) The extraction negative pressure optimization method for the goaf of the coal mine can, by collecting the extraction data and geological environment data of several boreholes of each extraction well in each permeable area, combining the calculated comprehensive extraction negative pressure index and the geological extraction correction index, scientifically evaluate and analyze the influence of geological conditions on gas extraction, and through the precise analysis of geological characteristics, implement differential optimization measures for different geological conditions, thereby improving the accuracy and efficiency of the extraction process.

[0019] (3) The extraction negative pressure optimization method for the goaf of the coal mine can, by combining the comprehensive extraction negative pressure correction index and implementing targeted optimization measures, rationally allocate extraction resources, avoid excessive adjustment of extraction negative pressure, optimize the use efficiency of extraction equipment, and at the same time, precise negative pressure control reduces gas waste and leakage in the coal mine, thus ensuring the efficient utilization of resources.

[0020] Of course, it is not necessary for any product implementing the present invention to achieve all the above-mentioned advantages simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flowchart of an extraction negative pressure optimization method for the goaf of a coal mine according to the present invention.

[0022] Figure 2This is the flowchart of the steps to obtain several permeable regions of the coal mine goaf to be optimized in the method for optimizing the drainage negative pressure of the drainage boreholes in the coal mine goaf of the present invention.

[0023] Figure 3 This is the flowchart of the steps to obtain the comprehensive drainage negative pressure index of each drainage borehole of each drainage well in each permeable region of the coal mine goaf to be optimized in the method for optimizing the drainage negative pressure of the drainage boreholes in the coal mine goaf of the present invention. Specific implementation manners

[0024] The general idea for the problems in the embodiments of this application is as follows:

[0025] Divide the coal mine goaf into regions to obtain several drainage regions of the coal mine goaf to be optimized, and obtain the roof image data of the corresponding regions, conduct identification and analysis to obtain several permeable regions of the coal mine goaf to be optimized. Secondly, obtain the drainage data and geological environment data of several drainage boreholes of several drainage wells in each permeable region of the coal mine goaf to be optimized, and conduct data analysis respectively to obtain the comprehensive drainage negative pressure index and geological drainage correction index of each drainage borehole of the coal mine goaf to be optimized, and conduct comprehensive analysis to obtain the comprehensive drainage negative pressure correction index of each permeable region. Finally, take corresponding optimization measures based on the comprehensive drainage negative pressure correction index of each permeable region.

[0026] Please refer to Figure 1 , an embodiment of the present invention provides a technical solution: a method for optimizing the drainage negative pressure of the drainage boreholes in the coal mine goaf, including the following steps: When extracting gas from the coal mine goaf, conduct regional division processing (divide based on a preset range) to obtain several drainage regions of the coal mine goaf to be optimized, and obtain the roof image data of the corresponding regions, conduct identification and analysis to obtain several permeable regions of the coal mine goaf to be optimized (that is, the types of permeable regions corresponding to the drainage regions); and obtain the drainage data and geological environment data of several drainage boreholes of several drainage wells in each permeable region of the coal mine goaf to be optimized, and conduct data analysis respectively to obtain the comprehensive drainage negative pressure index and geological drainage correction index of each drainage borehole of each drainage well in each permeable region of the coal mine goaf to be optimized, and conduct comprehensive analysis to obtain the comprehensive drainage negative pressure correction index of each permeable region of the coal mine goaf to be optimized; and take corresponding optimization measures based on the comprehensive drainage negative pressure correction index of each permeable region of the coal mine goaf to be optimized.

[0027] The specific formula for calculating the comprehensive drainage negative pressure correction index of each permeable region of the coal mine goaf to be optimized is as follows: Among them, ZxF g is the comprehensive drainage negative pressure correction index of the g-th permeable region of the coal mine goaf to be optimized, FyZ ghb , DzFghb are the comprehensive drainage negative pressure index and the geological drainage correction index of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the coal mine goaf to be optimized, respectively, ε 1 , ε 2 are the comprehensive drainage negative pressure coefficient and the geological correction coefficient stored in the database, respectively, ε 1 +ε 2 = 1, g = 1, 2, 3,..., g 0 , g 0 is the number of permeable areas, h = 1, 2, 3,..., h 0 , h 0 is the number of drainage wells, b = 1, 2, 3,..., b 0 , b 0 is the number of drainage boreholes, e is the natural constant, and its value is 2.71 in this embodiment.

[0028] It should be noted that ε 1 , ε 2 can be obtained through the following steps: read the comprehensive drainage negative pressure index and the geological drainage correction index of each drainage borehole of each drainage well in each permeable area of the coal mine goaf to be optimized, and conduct mean analysis to obtain the mean value of the comprehensive drainage negative pressure index and the mean value of the geological drainage correction index of the coal mine goaf to be optimized, and conduct summation analysis to obtain the sum value of the comprehensive drainage negative pressure correction, and conduct ratio analysis on the mean value of the comprehensive drainage negative pressure index and the mean value of the geological drainage correction index of the coal mine goaf to be optimized respectively with the sum value of the comprehensive drainage negative pressure correction, and use the ratio analysis as the corresponding coefficient.

[0029] The specific embodiment of calculating the comprehensive drainage negative pressure correction index of the first permeable area of the coal mine goaf to be optimized is as follows. There are two drainage wellheads in the first permeable area. The first drainage wellhead contains three drainage boreholes, and the second drainage wellhead contains five drainage boreholes. And the existing data are as follows:

[0030] The comprehensive drainage negative pressure indexes of the three drainage boreholes of the first drainage wellhead in the first permeable area are: 1.26, 1.39, 1.03 in sequence.

[0031] The geological drainage correction indexes of the three drainage boreholes of the first drainage wellhead in the first permeable area are: 0.89, 0.76, 0.91 in sequence.

[0032] The comprehensive drainage negative pressure indexes of the five drainage boreholes of the second drainage wellhead in the first permeable area are: 1.39, 1.58, 1.69, 1.21, 1.46 in sequence.

[0033] The geological extraction correction indices of the five extraction boreholes at the second extraction wellhead in the first seepage area are successively: 0.63, 0.83, 0.84, 0.62, 0.89.

[0034] The comprehensive extraction negative pressure coefficient and the geological correction coefficient stored in the database are successively approximately: 0.63, 0.37.

[0035] Substitute the above data into the formula for the comprehensive extraction negative pressure correction index of each seepage area in the goaf of the coal mine to be optimized for calculation, and obtain: 0.49 0.53

[0036] The comprehensive extraction negative pressure correction index of the first seepage area in the goaf of the coal mine to be optimized = (1 / 2) * ((1 / 3) * (ln(1 + (0.63 * 1.26 + 0.37 * 0.89) / (2.71 - 1)) + ln(1 + (0.63 * 1.39 + 0.37 * 0.76) / (2.71 - 1)) + ln(1 + (0.63 * 1.03 + 0.37 * 0.91) / (2.71 - 1))) + (1 / 5) * (ln(1 + (0.63 * 1.39 + 0.37 * 0.63) / (2.71 - 1)) + ln(1 + (0.63 * 1.58 + 0.37 * 0.83) / (2.71 - 1)) + ln(1 + (0.63 * 1.69 + 0.37 * 0.84) / (2.71 - 1)) + ln(1 + (0.63 * 1.21 + 0.37 * 0.62) / (2.71 - 1)) + ln(1 + (0.63 * 1.46 + 0.37 * 0.89) / (2.71 - 1)))) ≈ 0.51.

[0037] The roof image data specifically includes the pixel value and two-dimensional coordinates of each roof pixel point. The extraction data includes the extraction volume value, borehole depth value, borehole cross-sectional area value, temperature value, gas concentration value, pressure gradient index, gas viscosity value, and borehole length value. The geological environment data includes the porosity value, stress index, adsorption value, and the inclination angle value, aperture value, and extension depth value of each crack (the crack in the extraction borehole).

[0038] Among them, the two-dimensional coordinates take the upper left corner of the roof image as the origin, the horizontal axis of the roof image as the X-axis, and the vertical axis of the roof image as the Y-axis.

[0039] The extraction volume value is the amount of gas extracted from the borehole per unit time, which can be measured and obtained through a flowmeter.

[0040] The borehole depth value is the longitudinal distance value of the extraction borehole from the extraction inlet, which can be obtained through an acoustic depth sounder.

[0041] The gas concentration value can be obtained through a gas analyzer.

[0042] The pressure gradient index is the degree of change in pressure per unit distance, that is, the pressure values at multiple monitoring points of the extraction borehole are obtained (which can be obtained through pressure sensors), and standard deviation processing is performed. The processing result is the pressure gradient index.

[0043] The gas viscosity value is the viscosity of gas flow, that is, the resistance, which can be obtained through a viscometer.

[0044] The borehole length value is the total length of the extraction borehole from the surface to the bottom of the borehole, which can be obtained through a laser depth measuring instrument.

[0045] The stress index is the comprehensive value of the stresses in multiple directions on the coal seam where the extraction borehole is located. It can be obtained through the following steps, that is, weighted processing is performed on the stresses in multiple directions, and the weighted processing result is the stress index.

[0046] The adsorption value is the ability of the coal seam where the extraction borehole is located to adsorb gas, which can be obtained through a BET surface analyzer.

[0047] The inclination angle value is the inclination angle of the fracture, that is, the degree of inclination of the fracture relative to the horizontal plane, which can be obtained through a geological compass.

[0048] The aperture value is the width of the fracture, which can be obtained through a laser scanner (calculated and analyzed based on the internal imaging technology).

[0049] The extension depth value is the longitudinal extension depth of the fracture in the coal seam, that is, the length of the fracture in the vertical direction, which can be obtained through a ground penetrating radar (GPR can penetrate the ground, detect the depth of the fracture, and calculate the depth of the fracture through the time difference of the reflected waves).

[0050] Specifically, such as Figure 2As shown in the figure, the specific steps to obtain several seepage regions of the coal mine goaf to be optimized are as follows: Edge detection is performed on the pixel values of each roof pixel point in each extraction area of the coal mine goaf to be optimized to obtain several crack edge pixel points in the roof image of each extraction area of the coal mine goaf to be optimized; and connectivity processing is performed on each crack edge pixel point in the roof image of each extraction area of the coal mine goaf to be optimized to obtain several roof crack regions in each extraction area of the coal mine goaf to be optimized; and comprehensive analysis is performed on the two-dimensional coordinates of each crack edge pixel point in each roof crack region of each extraction area of the coal mine goaf to be optimized to obtain the perimeter value and area value of each roof crack region in each extraction area of the coal mine goaf to be optimized, and comprehensive analysis is performed to obtain the morphological index of each roof crack region in each extraction area of the coal mine goaf to be optimized; the pixel values of each roof pixel point in each roof crack region of each extraction area of the coal mine goaf to be optimized are processed by standard deviation to obtain the texture index of each roof crack region in each extraction area of the coal mine goaf to be optimized, and comprehensive analysis is performed in combination with the morphological index to obtain the seepage characteristic index of each extraction area of the coal mine goaf to be optimized, and judgment analysis is performed with the preset seepage characteristic index threshold interval to obtain several seepage regions of the coal mine goaf to be optimized.

[0051] Among them, the edge detection processing used here is Canny edge detection (denoising by Gaussian filtering, calculating the gradient intensity, finding the edges, and using the double-threshold method to retain important edges).

[0052] The connectivity processing used here is 8-connectivity (that is, all eight adjacent directions).

[0053] The specific process of judgment analysis is as follows: If the seepage characteristic index of the extraction area of the coal mine goaf to be optimized is lower than the lower limit (i.e., the minimum value) of the preset seepage characteristic index threshold interval, then mark this extraction area as a low-permeability area;

[0054] If the seepage characteristic index of the extraction area of the coal mine goaf to be optimized is within the preset seepage characteristic index threshold interval, then mark this extraction area as a medium-permeability area;

[0055] If the seepage characteristic index of the extraction area of the coal mine goaf to be optimized is higher than the upper limit (i.e., the maximum value) of the preset seepage characteristic index threshold interval, then mark this extraction area as a high-permeability area.

[0056] And the specific formulas for calculating the perimeter value, area value, and texture index of each roof crack region in each extraction area of the coal mine goaf to be optimized are as follows:

[0057]

[0058] Among them, ZcL ij is the perimeter value of the j-th roof crack area in the i-th extraction area of the goaf of the coal mine to be optimized. (X ij(m+1) , Y ij(m+1) ) is the two-dimensional coordinate of the (m + 1)-th crack edge pixel point in the j-th roof crack area of the i-th extraction area of the goaf of the coal mine to be optimized. (X ijm , Y ijm ) is the two-dimensional coordinate of the m-th crack edge pixel point in the j-th roof crack area of the i-th extraction area of the goaf of the coal mine to be optimized. (X ij1 , Y ij1 ) is the two-dimensional coordinate of the 1st crack edge pixel point in the j-th roof crack area of the i-th extraction area of the goaf of the coal mine to be optimized. ZaL ij is the area value of the j-th roof crack area in the i-th extraction area of the goaf of the coal mine to be optimized. ξ is the proportionality coefficient stored in the database, and takes the value of 0.5 in this implementation example. i = 1, 2, 3,..., i 0 , i 0 is the number of extraction areas, j = 1, 2, 3,..., j 0 , j 0 is the number of roof crack areas, m = 1, 2, 3,..., m 0 , m 0 is the number of crack edge pixel points.

[0059] The specific formulas for calculating the morphological index and permeability characteristic index of each roof crack area in each extraction area of the goaf of the coal mine to be optimized are as follows: Among them, XtZ ij is the morphological index of the j-th roof crack area in the i-th extraction area of the goaf of the coal mine to be optimized. ZcL ij is the perimeter value of the j-th roof crack area in the i-th extraction area of the goaf of the coal mine to be optimized. ZaL ij is the area value of the j-th roof crack area in the i-th extraction area of the goaf of the coal mine to be optimized. ω is the adjustment coefficient stored in the database, and takes the value of 4 in this implementation example. π is the circumference ratio, and takes the value of 3.14 in this implementation example. WqS i is the permeability characteristic index of the i-th extraction area of the goaf of the coal mine to be optimized. α 1 is the morphological coefficient stored in the database. WzS ij is the texture index of the j-th roof crack area in the i-th extraction area of the goaf of the coal mine to be optimized. α 2 is the texture coefficient stored in the database. α 1 +α 2 = 1. η is the interaction coefficient stored in the database. i = 1, 2, 3,..., i0 , i 0 is the number of drainage areas, j = 1, 2, 3, ..., j 0 , j 0 is the number of roof crack areas.

[0060] It should be noted that α 1 , α 2 can be obtained through the following steps: Read the morphological index and texture index of each roof crack area in each drainage area of the goaf of the coal mine to be optimized (it should be noted that both the morphological index and the texture index are dimensionless values and can be directly calculated), perform mean analysis to obtain the mean morphological index and mean texture index of the goaf of the coal mine to be optimized, and perform summation analysis to obtain the permeability sum value, and perform ratio analysis on the mean morphological index and mean texture index of the goaf of the coal mine to be optimized with the permeability sum value respectively, and use the ratio results as the corresponding coefficients.

[0061] And the term η*XtZ ij *WzS ij in the formula is used to adjust the superposition effect of the morphological index and texture index of each roof crack area to prevent the penetration characteristic index from being too high or too low.

[0062] η can be obtained through the following steps: Use historical image data, combine indicators such as morphological index and texture index, perform statistical regression analysis, quantify the specific impact of the superposition of various factors on the penetration characteristic index, so as to fit the initial weight value. Secondly, use the sensitivity analysis method to adjust the value range of the coefficient, observe its impact on the evaluation result of the penetration characteristic index, and based on the regional characteristics, correct and optimize the preliminarily fitted coefficient, and finally determine the coefficient value applicable to this area.

[0063] In this implementation plan, by performing gray processing, edge detection and connectivity processing on the roof pixel points of the coal mine goaf, the crack edges and crack areas in the roof image can be accurately identified. These crack areas directly affect the gas drainage effect and improve the positioning accuracy of the penetration area, and can provide reliable basic data for subsequent drainage optimization. Secondly, by comprehensively analyzing the morphological index and texture index of each crack area, the morphological characteristics and surface texture information of the crack can be quantified, which helps to reveal the penetration characteristics of the coal mine goaf, provides an important basis for judging the permeability of the penetration area, gas release and its impact on the drainage effect, and can perform more accurate optimization based on these data. Finally, through the quantified penetration characteristic index, morphological index and texture index, combined with specific threshold interval judgment, it can help coal mine management personnel to timely identify and optimize the key areas in the gas drainage process, thereby improving the drainage efficiency and further enhancing the overall production efficiency and safety of the coal mine.

[0064] Specifically, as Figure 3 shown, the specific steps for obtaining the comprehensive drainage negative pressure index of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized are as follows: Obtain the well depth value of each drainage well and the temperature reference value of each drainage borehole in each permeable area of the goaf of the coal mine to be optimized, and conduct a comprehensive analysis in combination with the drainage volume value, temperature value, borehole depth value, and borehole cross-sectional area value to obtain the initial drainage negative pressure index of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized; and conduct a comprehensive analysis on the gas concentration value, pressure gradient index, gas viscosity value, and borehole length value of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized to obtain the drainage efficiency index and gas flowability index of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized; and perform standardization processing (i.e., unit removal processing) on the initial drainage negative pressure index, drainage efficiency index, and gas flowability index of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized; and conduct a comprehensive analysis based on the initial drainage negative pressure index, drainage efficiency index, and gas flowability index of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized after standardization processing to obtain the comprehensive drainage negative pressure index of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized.

[0065] Among them, the temperature reference value can be obtained through the following steps: Obtain the historical temperature values of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized for several times in history, and conduct a mean value analysis. The result of the mean value analysis is the temperature reference value.

[0066] The well depth value is the depth value of the drainage well and can be obtained by an acoustic depth sounder.

[0067] The specific formulas for calculating the initial drainage negative pressure index and comprehensive drainage negative pressure index of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized are as follows: Among them, CyF ghb is the initial drainage negative pressure index of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the goaf of the coal mine to be optimized, LcZ ghb is the drainage volume value of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the goaf of the coal mine to be optimized, DzP ghb is the borehole cross-sectional area value of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the goaf of the coal mine to be optimized, χ is the gas constant stored in the database, and in this embodiment, it takes the value of 8.314, WdZ ghb is the temperature value of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the goaf of the coal mine to be optimized, CwDghb is the temperature reference value of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the goaf of the coal mine to be optimized, ZkS ghb is the borehole depth value of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the goaf of the coal mine to be optimized, SdZ gh is the well depth value of the h-th drainage well in the g-th permeable area of the goaf of the coal mine to be optimized, FyZ ghb is the comprehensive drainage negative pressure index of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the goaf of the coal mine to be optimized, CyF′ ghb 、LtX′ ghb 、XcL′ ghb are the initial drainage negative pressure index, drainage efficiency index, and gas flowability index of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the goaf of the coal mine to be optimized after standardization processing, β 1 、β 2 、β 3 are the initial coefficient, drainage efficiency coefficient, and gas flow coefficient stored in the database in sequence, β 1 +β 2 +β 3 =1, g = 1, 2, 3,...., g 0 , g 0 is the number of permeable areas, h = 1, 2, 3,...., h 0 , h 0 is the number of drainage wells, b = 1, 2, 3,...., b 0 , b 0 is the number of drainage boreholes, e is the natural constant, and its value is 2.71 in this embodiment.

[0068] It should be noted that β 1 、β 2 、β 3 can be obtained through the following steps: Read the initial drainage negative pressure index, drainage efficiency index, and gas flowability index of each drainage borehole of each drainage well in each permeable area of the goaf of the coal mine to be optimized after standardization processing, perform mean analysis to obtain the mean values of the initial drainage negative pressure index, drainage efficiency index, and gas flowability index of the goaf of the coal mine to be optimized after standardization processing, and perform summation analysis to obtain the sum of the drainage negative pressures. Then, perform ratio analysis on the mean values of the initial drainage negative pressure index, drainage efficiency index, and gas flowability index of the goaf of the coal mine to be optimized after standardization processing with the sum of the drainage negative pressures respectively, and use the results of the ratio analysis as the corresponding coefficients.

[0069] In this implementation plan, through comprehensive analysis of the initial drainage negative pressure index, drainage efficiency index, and gas flowability index of each drainage borehole in each permeable area, the working conditions of drainage are comprehensively evaluated from multiple dimensions, so as to reflect the actual situation of negative pressure in the gas drainage process and perform standardized processing on it, eliminating the differences between units, making the data comparable, and further helping to improve the data consistency of different permeable areas, drainage wells, and boreholes. Subsequently, it provides a more accurate and reliable basis for the drainage optimization of the goaf in coal mines. Secondly, through comprehensive analysis of the standardized indexes, after obtaining the comprehensive drainage negative pressure index, the gas drainage conditions in different permeable areas can be comprehensively evaluated. At the same time, combined with the drainage efficiency and gas flowability indexes, the drainage strategy can be accurately adjusted to maximize the drainage effect of each borehole, thereby improving the overall gas drainage efficiency and economic benefits.

[0070] Specifically, the specific steps to obtain the drainage efficiency index and gas flowability index of each drainage borehole in each drainage well in each permeable area of the goaf to be optimized are as follows: Read the drainage volume values of each drainage borehole in each drainage well in each permeable area of the goaf to be optimized, and obtain the borehole volume value (of each drainage borehole); comprehensively analyze the drainage volume values and borehole volume values of each drainage borehole in each drainage well in each permeable area of the goaf to be optimized to obtain the drainage efficiency index of each drainage borehole in each drainage well in each permeable area of the goaf to be optimized; obtain the permeability value, humidity value, and humidity reference value of each drainage borehole in each drainage well in each permeable area of the goaf to be optimized, and comprehensively analyze them in combination with the pressure gradient index, gas viscosity value, and borehole length value to obtain the gas flowability index of each drainage borehole in each drainage well in each permeable area of the goaf to be optimized.

[0071] Among them, the borehole volume value is the volume of the effective space in the drainage borehole, that is, the borehole volume value = borehole depth value * borehole cross-sectional area value.

[0072] The permeability value is the permeability of the coal seam where the drainage borehole is located, which can be obtained through a gas permeameter.

[0073] The humidity value can be obtained through a humidity sensor.

[0074] The steps to obtain the well depth value of each drainage well and the humidity reference value of each drainage borehole in each permeable area of the goaf to be optimized are the same as those for the temperature reference value.

[0075] And the specific formulas for calculating the drainage efficiency index and gas flowability index of each drainage borehole in each drainage well in each permeable area of the goaf to be optimized are as follows: Among them, LtX ghbThe extraction efficiency index of the b-th extraction borehole of the h-th extraction well in the g-th permeation area of the goaf of the coal mine to be optimized, LcZ ghb 、WsD ghb 、ZtD ghb The extraction volume value, gas concentration value, and borehole volume value of the b-th extraction borehole of the h-th extraction well in the g-th permeation area of the goaf of the coal mine to be optimized, XcL ghb The gas flowability index of the b-th extraction borehole of the h-th extraction well in the g-th permeation area of the goaf of the coal mine to be optimized, StL ghb 、YtL ghb 、QtD ghb 、ZsD ghb 、ZdS ghb 、CdS ghb The permeability value, pressure gradient index, gas viscosity value, borehole length value, humidity value, humidity reference value of the b-th extraction borehole of the h-th extraction well in the g-th permeation area of the goaf of the coal mine to be optimized, τ is the humidity adjustment coefficient stored in the database, g = 1, 2, 3,..., g 0 ,g 0 is the number of permeation areas, h = 1, 2, 3,..., h 0 ,h 0 is the number of extraction wells, b = 1, 2, 3,..., b 0 ,b 0 is the number of extraction boreholes.

[0076] It should be noted that τ can be obtained in the following way: Based on the historical humidity values of the region, determine the initial influence weight of humidity on the gas flowability index through statistical regression analysis. Then, use the sensitivity analysis method to adjust the value range of the coefficient to evaluate the stability and applicability of the humidity to the formula output. Next, further fit the weight through model optimization (such as machine learning algorithms) to ensure that the formula can accurately reflect the actual gas flowability, and fine-tune the coefficient based on different regional characteristics to ensure its applicability to specific gas flow assessment requirements.

[0077] In this implementation plan, by comprehensively analyzing multiple factors such as gas extraction volume, borehole volume, permeability, and humidity, the gas extraction efficiency and gas flowability of each gas extraction borehole are comprehensively evaluated, so as to help coal mine managers accurately understand the gas extraction performance and gas fluidity of each borehole. Secondly, the influence of humidity on gas flowability is taken into consideration, and the humidity adjustment coefficient is further optimized through sensitivity analysis and machine learning algorithms to ensure that the influence of humidity change on gas flow can be accurately reflected in the gas flowability index, thereby improving the overall gas extraction efficiency and safety. Finally, the accurate calculation of the gas extraction efficiency index and gas flowability index helps to better understand the working state of each gas extraction borehole and the effect of gas extraction, and combined with targeted optimization measures, it can improve the gas extraction efficiency and reduce the risk of gas accumulation, thus ensuring the safety of mine operations.

[0078] Specifically, the specific steps to obtain the geological gas extraction correction index of each gas extraction borehole in each extraction well in each permeable area of the goaf of the coal mine to be optimized are as follows: Obtain the stress reference index of each gas extraction borehole in each extraction well in each permeable area of the goaf of the coal mine to be optimized, and perform normalization processing (i.e., unit removal) in combination with the porosity value, stress index, and adsorption value; and comprehensively analyze the porosity value, stress index, adsorption value, and stress reference index of each gas extraction borehole in each extraction well in each permeable area of the goaf of the coal mine to be optimized after normalization processing to obtain the geological gas extraction rate correction index of each gas extraction borehole in each extraction well in each permeable area of the goaf of the coal mine to be optimized; Obtain the inclination angle reference value, aperture reference value, and extension depth reference value of each gas extraction borehole in each extraction well in each permeable area of the goaf of the coal mine to be optimized, and comprehensively analyze them in combination with the inclination angle value, aperture value, and extension depth value of each crack to obtain the geological fluidity correction index of each gas extraction borehole in each extraction well in each permeable area of the goaf of the coal mine to be optimized; and comprehensively analyze the geological gas extraction rate correction index and geological fluidity correction index of each gas extraction borehole in each extraction well in each permeable area of the goaf of the coal mine to be optimized to obtain the geological gas extraction correction index of each gas extraction borehole in each extraction well in each permeable area of the goaf of the coal mine to be optimized.

[0079] Among them, the specific formulas for calculating the geological gas extraction rate correction index, geological fluidity correction index, and geological gas extraction correction index of each gas extraction borehole in each extraction well in each permeable area of the goaf of the coal mine to be optimized are as follows: Among them, DzC ghb is the geological gas extraction rate correction index of the b-th gas extraction borehole in the h-th extraction well in the g-th permeable area of the goaf of the coal mine to be optimized, KxD′ ghb 、YzL′ ghb 、XzF′ ghbThey are the porosity value, stress index, and adsorption value of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the coal mine goaf to be optimized after normalization, YzL′ ghb is the stress reference index of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the coal mine goaf to be optimized after normalization They are the pore coefficient, stress coefficient, and adsorption coefficient stored in the database DzL ghb is the geological fluidity correction index of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the coal mine goaf to be optimized, QxD ghbu , KxD ghbu , YsD ghbu They are the inclination angle value, aperture value, and extension depth value of the u-th crack of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the coal mine goaf to be optimized, CkQ ghb , CdK ghb , CkY ghb They are the inclination angle reference value, aperture reference value, and extension depth reference value of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the coal mine goaf to be optimized, λ 1 , λ 2 , λ 3 They are the inclination coefficient, aperture coefficient, and extension coefficient stored in the database, DzF ghb is the geological drainage correction index of the b-th drainage borehole of the h-th drainage well in the g-th permeable area of the coal mine goaf to be optimized, ψ 1 , ψ 2 They are the rate coefficient and flow coefficient stored in the database, ψ 1 +ψ 2 = 1, g = 1, 2, 3,..., g 0 , g 0 is the number of permeable areas, h = 1, 2, 3,..., h 0 , b 0 is the number of drainage wells, b = 1, 2, 3,..., b 0 , b 0 is the number of drainage boreholes, u = 1, 2, 3,..., u 0 , u 0 is the number of cracks, e is the natural constant, and its value is 2.71 in this embodiment

[0080] It should be noted that It can be obtained through the following steps: Read the porosity values, stress indices, and adsorption values of each drainage borehole in each drainage well in each permeable area of the coal mine goaf to be optimized after normalization, conduct mean analysis to obtain the mean porosity, mean stress index, and mean adsorption of the coal mine goaf to be optimized after normalization, and conduct summation analysis to obtain the corrected sum value of the drainage rate. Then, conduct ratio analysis on the mean porosity, mean stress index, and mean adsorption of the coal mine goaf to be optimized after normalization with the corrected sum value of the drainage rate respectively, and use the results of the ratio analysis as the corresponding coefficients.

[0081] λ 1 、λ 2 、λ 3 It can be obtained through the following steps: First, use historical geological environment data. By analyzing the dynamic changes of variables (such as inclination angle value, aperture value, extension depth value), adopt statistical regression methods to quantify the initial influence degree of each variable on the geological fluidity correction index, so as to obtain the initial coefficient values. Then, based on sensitivity analysis techniques, adjust the value ranges of these coefficients in different environmental scenarios. Subsequently, calibrate the model through scenario analysis to optimize the rationality and stability of the parameter values.

[0082] ψ 1 、ψ 2 It can be obtained through the following steps: Read the geological drainage rate correction index and geological fluidity correction index of each drainage borehole in each drainage well in each permeable area of the coal mine goaf to be optimized, conduct mean analysis to obtain the mean geological drainage rate correction index and mean geological fluidity correction index of the coal mine goaf to be optimized, and conduct summation analysis to obtain the comprehensive correction sum value. Then, conduct ratio analysis on the mean geological drainage rate correction index and mean geological fluidity correction index of the coal mine goaf to be optimized with the comprehensive correction sum value respectively, and use the results of the ratio analysis as the corresponding coefficients.

[0083] In this implementation plan, by normalizing geological parameters such as porosity, stress index, and adsorption value, and comprehensively analyzing them in combination with the stress reference index and fracture characteristics (such as inclination angle, aperture, and extension depth), the geological conditions of the coal seam can be accurately evaluated, thereby helping to accurately understand the physical properties of the coal seam (such as gas mobility and adsorption capacity) and its impact on the extraction process, and further providing basic data for optimizing the extraction plan. Secondly, by combining the normalized geological parameters and fracture characteristics, the calculated geological extraction rate correction index and geological mobility correction index can dynamically reflect the impact of different coal seam characteristics on the extraction process. By quantifying these variables, the extraction rate and gas flowability of each extraction borehole can be precisely adjusted, which helps to flexibly adjust the extraction plan in a complex geological environment and optimize the gas extraction efficiency. Finally, through the comprehensive analysis of the geological extraction rate correction index and the geological mobility correction index, energy waste can be reduced, the gas extraction efficiency can be improved, and the economic benefits of the coal mine can be increased.

[0084] Specifically, the specific steps for taking corresponding optimization measures based on the comprehensive extraction negative pressure correction index of each permeable area in the goaf of the coal mine to be optimized are as follows: Compare and analyze the comprehensive extraction negative pressure correction index of each permeable area in the goaf of the coal mine to be optimized with the preset comprehensive extraction negative pressure correction index threshold respectively; if the comprehensive extraction negative pressure correction index of each permeable area in the goaf of the coal mine to be optimized is lower than or equal to the preset comprehensive extraction negative pressure correction index threshold, then take the first extraction negative pressure optimization measure (i.e., provide negative pressure increase to relevant personnel: by adjusting the wellhead negative pressure, increasing the gas mobility, promoting more gas to flow towards the extraction boreholes, and improving the extraction effect; optimizing the extraction equipment: upgrading or adjusting the efficiency of the extraction equipment, such as replacing a more efficient pump and strengthening the sealing of the extraction equipment; adjusting geological parameters: adjusting the layout of the extraction wells, borehole depth, or opening method to improve the extraction effect); if the comprehensive extraction negative pressure correction index of each permeable area in the goaf of the coal mine to be optimized is higher than the preset comprehensive extraction negative pressure correction index threshold, then take the second extraction negative pressure optimization measure (i.e., provide negative pressure reduction to relevant personnel: by reducing the negative pressure, avoiding equipment wear, pipeline deformation, or excessive gas dilution caused by too high negative pressure; adjusting the extraction area configuration: adjusting the layout of the extraction wells or optimizing the borehole spacing to ensure a more uniform negative pressure distribution; energy efficiency management measures: improving the energy efficiency ratio of the equipment, such as optimizing the configuration of the extraction pump and reasonably adjusting the extraction load, etc., to reduce unnecessary energy consumption).

[0085] In this implementation plan, corresponding measures are taken for different negative pressure situations to ensure that the gas fluidity and extraction efficiency are in the best state. For example, when the negative pressure is low, the negative pressure is increased to promote the flow of gas, thereby increasing the extraction volume; while when the negative pressure is too high, the negative pressure is reduced to avoid equipment overload and ensure the stable operation of gas extraction. At the same time, by reasonably adjusting the negative pressure, not only can the extraction effect be ensured, but also the equipment failure rate can be reduced and the service life of the equipment can be extended. For example, when the negative pressure is too low, the gas emission is insufficient, and too high negative pressure is likely to cause uneven extraction, even leading to equipment failures or safety accidents. By precisely controlling the negative pressure, the safety of coal mine operations can be effectively improved. Finally, optimization measures are taken separately according to the specific conditions of each penetration area, making the extraction process more refined and personalized, which helps to improve the overall management level of the coal mine.

[0086] In summary, this application has at least the following effects:

[0087] By identifying the penetration areas in the goaf of the coal mine, customized optimization measures are implemented for each extraction area, and through the comprehensive analysis of the geological environment and the negative pressure index, the efficiency of gas extraction can be effectively improved, avoiding gas leakage and accumulation caused by insufficient negative pressure or over-extraction, thus ensuring the production safety of the mine, reducing the accident risk, and enhancing the safety and extraction efficiency of the mine.

[0088] By collecting the extraction data and geological environment data of several boreholes of each extraction well in each penetration area, combining the calculated comprehensive extraction negative pressure index and the geological extraction correction index, the influence of geological conditions on gas extraction can be scientifically evaluated and analyzed, and combined with the precise analysis of geological characteristics, differential optimization measures can be implemented for different geological conditions, thereby improving the accuracy and efficiency of the extraction process.

[0089] By combining the comprehensive extraction negative pressure correction index and implementing targeted optimization measures, the extraction resources can be reasonably allocated, and excessive adjustment of extraction negative pressure can be avoided, thereby optimizing the use efficiency of extraction equipment. At the same time, precise negative pressure control reduces gas waste and leakage in the coal mine, ensuring the efficient use of resources.

[0090] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0091] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A method for optimizing negative pressure of drilling holes for extraction in coal mine goaf, characterized in that: The following steps are involved: When extracting gas from the coal mine goaf, the area division process is performed to obtain several extraction areas of the coal mine goaf to be optimized, and the roof image data of the corresponding area is obtained to perform identification analysis to obtain several permeability areas of the coal mine goaf to be optimized; And obtain the extraction data and geological environment data of several extraction boreholes of several extraction wells in each permeable area of ​​the coal mine goaf to be optimized, and perform data analysis respectively to obtain the comprehensive extraction negative pressure index and geological extraction correction index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized, and perform comprehensive analysis to obtain the comprehensive extraction negative pressure correction index of each permeable area of ​​the coal mine goaf to be optimized; Corresponding optimization measures are taken based on the comprehensive extraction negative pressure correction index of each permeable area in the coal mine goaf to be optimized.

2. The method for optimizing negative pressure of coal mine goaf extraction drilling according to claim 1, characterized in that: The roof image data specifically includes the pixel value and two-dimensional coordinates of each roof pixel point; the extraction data includes the extraction amount value, drilling depth value, drilling cross-sectional area value, temperature value, gas concentration value, pressure gradient index, gas viscosity value, and drilling length value; the geological environment data includes porosity value, stress index, adsorption value, and the inclination angle value, opening value, and extension depth value of each crack.

3. The method for optimizing negative pressure of coal mine goaf extraction drilling according to claim 2, characterized in that: The specific steps of obtaining several permeable areas of the coal mine goaf to be optimized are as follows: Perform edge detection processing on the pixel value of each roof pixel point in each extraction area of ​​the coal mine goaf to be optimized, and obtain a number of crack edge pixel points in the roof image of each extraction area of ​​the coal mine goaf to be optimized; Connecting each crack edge pixel point in the roof image of each extraction area of ​​the coal mine goaf to be optimized is processed to obtain a number of roof crack areas of each extraction area of ​​the coal mine goaf to be optimized; And the two-dimensional coordinates of each crack edge pixel point of each roof crack area of ​​each extraction area in the coal mine goaf to be optimized are comprehensively analyzed respectively to obtain the perimeter value and area value of each roof crack area of ​​each extraction area in the coal mine goaf to be optimized, and a comprehensive analysis is performed to obtain the morphological index of each roof crack area of ​​each extraction area in the coal mine goaf to be optimized; The pixel values ​​of each roof pixel point in each roof crack area of ​​each extraction area in the coal mine goaf to be optimized are processed with standard deviation to obtain the texture index of each roof crack area of ​​each extraction area in the coal mine goaf to be optimized, and a comprehensive analysis is performed in combination with the morphological index to obtain the permeability characteristic index of each extraction area in the coal mine goaf to be optimized, and a judgment analysis is performed with the preset permeability characteristic index threshold range to obtain several permeability areas of the coal mine goaf to be optimized.

4. The method for optimizing negative pressure of coal mine goaf extraction drilling according to claim 3, characterized in that: The specific formula for calculating the morphological index and permeability characteristic index of each roof crack area in each extraction area of ​​the coal mine goaf to be optimized is as follows: Among them, XtZ ij is the morphological index of the jth roof crack area in the i-th extraction area of ​​the coal mine goaf to be optimized, ZcL ij ,ZaL ij are the perimeter and area values ​​of the jth roof crack area in the i-th extraction area of ​​the coal mine goaf to be optimized, ω is the adjustment coefficient stored in the database, π is the pi, WwqS i is the permeability characteristic index of the i-th extraction area in the coal mine goaf to be optimized, WzS ij is the texture index of the jth roof crack area in the ith extraction area of ​​the coal mine goaf to be optimized, α1, α2, and η are the morphological coefficient, texture coefficient, and interaction coefficient stored in the database respectively, α1+α2=1, i=1, 2, 3, …, i0, i0 is the number of extraction areas, j=1, 2, 3, …, j0, j0 is the number of roof crack areas.

5. The method for optimizing negative pressure of coal mine goaf extraction drilling according to claim 2, characterized in that: The specific steps for obtaining the comprehensive negative pressure index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized are as follows: The depth value of each extraction well in each permeable area of ​​the coal mine goaf to be optimized and the temperature reference value of each extraction borehole are obtained, and a comprehensive analysis is performed in combination with the extraction amount value, temperature value, borehole depth value, and borehole cross-sectional area value to obtain the initial extraction negative pressure index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized; A comprehensive analysis is conducted on the gas concentration value, pressure gradient index, gas viscosity value, and borehole length value of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized, and the extraction efficiency index and gas flowability index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized are obtained; The initial extraction negative pressure index, extraction efficiency index, and gas flowability index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized are standardized; Based on the standardized initial extraction negative pressure index, extraction efficiency index and gas flowability index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized, a comprehensive analysis is performed to obtain the comprehensive extraction negative pressure index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized.

6. The method for optimizing negative pressure of coal mine goaf extraction drilling according to claim 5, characterized in that: The specific steps for obtaining the extraction efficiency index and gas flowability index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized are as follows: Read the extraction volume value of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized, and obtain the borehole volume value; Comprehensively analyze the extraction quantity value and borehole volume value of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized, and obtain the extraction efficiency index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized; The permeability value, humidity value, and humidity reference value of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized are obtained, and a comprehensive analysis is performed in combination with the pressure gradient index, gas viscosity value, and borehole length value to obtain the gas flowability index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized.

7. The method for optimizing negative pressure of coal mine goaf extraction drilling according to claim 5, characterized in that: The specific formula for calculating the initial drainage negative pressure index and the comprehensive drainage negative pressure index of each drainage borehole of each drainage well in each permeable area of ​​the coal mine goaf to be optimized is as follows: Among them, CyF ghb is the initial negative pressure index of the bth drainage borehole of the hth drainage well in the gth permeable area of ​​the coal mine goaf to be optimized, LcZ ghb ,DzP ghb 、WdZ ghb , CwD ghb , ZkS ghb , SdZ gh are the extraction volume value, borehole cross-sectional area value, temperature value, temperature reference value, borehole depth value, and well depth value of the bth extraction borehole of the hth extraction well in the gth permeable area of ​​the coal mine goaf to be optimized, respectively. χ is the gas constant stored in the database, and FyZ ghb is the comprehensive negative pressure index of the bth extraction borehole of the hth extraction well in the gth permeable area of ​​the coal mine goaf to be optimized, CyF′ ghb , LtX′ ghb , XcL′ ghb They are respectively the initial drainage negative pressure index, drainage efficiency index and gas flow index of the bth drainage borehole of the hth drainage well in the gth permeable area of ​​the coal mine goaf to be optimized after standardized processing. β1, β2 and β3 are respectively the initial coefficient, drainage efficiency coefficient and gas flow coefficient stored in the database. β1+β2+β3=1, g=1, 2, 3, …, g0, g0 is the number of permeable areas, h=1, 2, 3, …, h0, h0 is the number of drainage wells, b=1, 2, 3, …, b0, b0 is the number of drainage boreholes, and e is a natural constant.

8. The method for optimizing negative pressure of coal mine goaf extraction drilling according to claim 2, characterized in that: The specific steps of obtaining the geological extraction correction index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized are as follows: Obtain the stress reference index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized, and perform normalization processing by combining the porosity value, stress index and adsorption value; And the porosity value, stress index, adsorption value and stress reference index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized after normalization processing are comprehensively analyzed to obtain the geological extraction rate correction index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized; Obtain the inclination angle reference value, opening reference value, and extension depth reference value of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized, and conduct a comprehensive analysis based on the inclination angle value, opening value, and extension depth value of each fracture to obtain the geological fluidity correction index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized; A comprehensive analysis is conducted on the geological extraction rate correction index and geological fluidity correction index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized, so as to obtain the geological extraction correction index of each extraction borehole of each extraction well in each permeable area of ​​the coal mine goaf to be optimized.

9. The method for optimizing negative pressure of coal mine goaf extraction drilling according to claim 1, characterized in that: The specific formula for calculating the comprehensive drainage negative pressure correction index of each permeable area in the coal mine goaf to be optimized is as follows: Among them, ZxF g is the comprehensive drainage negative pressure correction index of the gth permeable area in the coal mine goaf to be optimized, FyZ ghb ,DzF ghb They are the comprehensive drainage negative pressure index and geological drainage correction index of the bth drainage borehole of the hth drainage well in the gth permeable area of ​​the coal mine goaf to be optimized, ε1 and ε2 are the comprehensive drainage negative pressure coefficient and geological correction coefficient stored in the database, ε1+ε2=1, g=1,2,3,...,g0, g0 is the number of permeable areas, h=1,2,3,...,h0, h0 is the number of drainage wells, b=1,2,3,...,b0, b0 is the number of drainage boreholes, and e is a natural constant.

10. The method for optimizing negative pressure of coal mine goaf extraction drilling according to claim 1, characterized in that: The specific steps for taking corresponding optimization measures based on the comprehensive drainage negative pressure correction index of each permeable area in the coal mine goaf to be optimized are as follows: Compare and analyze the comprehensive drainage negative pressure correction index of each permeable area of ​​the coal mine goaf to be optimized with the preset comprehensive drainage negative pressure correction index threshold; If the comprehensive drainage negative pressure correction index of each permeable area of ​​the coal mine goaf to be optimized is lower than or equal to the preset comprehensive drainage negative pressure correction index threshold, the first drainage negative pressure optimization measure is adopted; If the comprehensive extraction negative pressure correction index of each permeable area in the coal mine goaf to be optimized is higher than the preset comprehensive extraction negative pressure correction index threshold, the second extraction negative pressure optimization measure is taken.

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