Rapid pressure relief and outburst elimination drill hole arrangement structure based on large-diameter drill holes

Abstract

The utility model discloses a rapid pressure relief and outburst elimination drill hole arrangement structure based on large-diameter drill holes, and belongs to the technical field of coal mine safety. Comprising strike bedding large-diameter drill holes formed in the middle of a coal seam and located in a coal seam working face, top plate large-diameter horizontal drill holes formed in a coal seam top plate, branch drill holes of the top plate large-diameter horizontal drill holes and bottom drainage roadway crossing extraction drill holes formed in a coal seam bottom plate. A plurality of strike bedding large-diameter drill holes are uniformly distributed in the coal seam working face at intervals; the roof large-diameter horizontal drills obliquely and upwards extend into the coal seam roof from the mining roadway drill site to the working face open-off cut direction, and the multiple roof large-diameter horizontal drills are evenly distributed on the upper portion in the horizontal direction. The coal seam outburst risk can be quickly eliminated under the combined action of the construction trend bedding large-diameter drill hole, the top plate large-diameter horizontal drill hole and the branch drill holes and the floor drainage roadway crossing hole, meanwhile, high stress accumulated in a roadway and surrounding rock can be reduced, elastic energy in the surrounding rock is reduced, and the coal seam outburst risk is reduced. The coal seam impact danger is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of coal mine safety, and in particular relates to a fast pressure relief and outburst elimination drilling arrangement structure based on large-diameter drilling. Background Art

[0002] Coal and gas outbursts and roof disasters have always been major challenges in the field of mining safety. As mining depth and intensity increase, problems such as stress concentration in the surrounding rock of deep tunnels and difficulty in extracting coal seam gas have hindered safe and efficient underground construction. The surrounding rock stress of the working face mining tunnel is disturbed, and there is severe deformation of the tunnel surrounding rock, which is difficult to maintain and easily leads to roof accidents. At the same time, the permeability of deep coal seams is low, and the gas pre-extraction period is further extended, which seriously affects the succession of mining and excavation.

[0003] At present, the existing gas control technologies include protective layer mining, coal seam mining and bottom extraction mining. With the development of large-diameter drilling equipment, large-diameter extraction boreholes for the construction of underground protruding coal seams have the characteristics of large gas flow and fast extraction speed. For example, patents with application publication numbers CN108798758A, CN109736876A and CN112364519A disclose large-diameter layer-by-layer drilling extraction technology for upper corners, which is mainly used to control upper corner gas; patents with application publication number CN115288607A disclose a large-diameter drilling pressure relief method for high-level stress zones in regional structures, which mainly controls local structural stress zones through large-diameter drilling; but the above-mentioned drilling pressure relief methods cannot achieve the control of complex disasters of deep gas coupled with roof disasters.

[0004] Therefore, it is necessary to develop a fast and efficient technology for preventing and controlling composite disasters in outburst coal seams, which is of great significance to improving the safety production level of coal mines. Utility Model Content

[0005] The purpose of the utility model is to overcome the shortcomings of the prior art and provide a rapid pressure relief and outburst elimination drilling hole arrangement structure based on large-diameter drilling holes, which can quickly eliminate the danger of coal seam outbursts by separately constructing large-diameter drilling holes in the direction of the layer and large-diameter horizontal drilling holes on the top plate and multiple branch drilling holes, and cooperating with the bottom extraction tunnel through-layer holes, while reducing the high stress accumulated in the tunnel and surrounding rock, reducing the elastic energy in the surrounding rock, and reducing the danger of coal seam impact.

[0006] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a fast pressure relief and outburst elimination drilling arrangement structure based on large-diameter drilling, including a large-diameter drilling hole arranged in the middle of the coal seam and located in the coal seam working face, a large-diameter horizontal drilling hole and its branch drilling hole arranged in the roof of the coal seam, and a bottom extraction laneway through-layer extraction drilling hole arranged in the bottom plate of the coal seam; a plurality of large-diameter drilling holes in the direction of the direction of the layer are evenly distributed in the coal seam working face and are arranged in parallel with the coal seam recovery lane, and the two sides of the drilling hole in the length direction are respectively the lower drift of the working face and the upper drift of the working face arranged in parallel. The longitudinal slot has two sides of the borehole in the radial direction that are connected with the drilling site of the mining tunnel and the cutting eye of the working face respectively; one end of the large-diameter horizontal borehole in the roof is connected with the drilling site of the mining tunnel, and the other end extends obliquely upward from the drilling site of the mining tunnel to the direction of the cutting eye of the working face into the coal seam roof, and multiple ones are evenly distributed in the horizontal direction on the upper part, and each large-diameter horizontal borehole in the roof has multiple branch boreholes evenly distributed downward, and the branch boreholes are connected between the large-diameter horizontal borehole in the roof and the top of the coal seam working face; one end of the bottom extraction tunnel through-layer extraction borehole is connected with the drilling site of the bottom extraction tunnel, and the other end extends obliquely upward to the bottom of the coal seam working face.

[0007] Furthermore, the large-diameter horizontal drill holes in the roof and the multiple branch drill holes together constitute large-diameter comb-shaped holes in the roof, and the design height of the large-diameter comb-shaped holes in the roof matches the height of the fracture zone.

[0008] Furthermore, the large-diameter boreholes along the strike direction and the large-diameter horizontal boreholes on the top plate are staggeredly distributed on the radial end surface of the boreholes.

[0009] Furthermore, the large-diameter boreholes along the strike direction are arranged in at least one layer, and the coal seam thickness is arranged as one layer if it is below 5m, and two layers if it is between 5m and 8m.

[0010] Furthermore, the design diameter Φ of the large-diameter borehole along the strike is 193 mm, the borehole spacing is 3.5 m, the distance from the coal seam floor is 2.5 m, and the hole depth matches the strike length of the coal seam working face.

[0011] Furthermore, the design diameter Φ of the large-diameter horizontal borehole in the roof is above 193 mm, and the hole depth matches the strike length of the coal seam working face.

[0012] The beneficial effects of the utility model are:

[0013] 1) The drilling arrangement structure of the utility model can quickly eliminate the danger of coal seam outburst by constructing large-diameter boreholes along the direction of the layer and large-diameter horizontal boreholes on the roof and multiple branch boreholes, and cooperate with the bottom extraction tunnel through-layer holes to reduce the high stress accumulated in the tunnel and surrounding rock, reduce the elastic energy in the surrounding rock, and reduce the danger of coal seam impact. The use of large-diameter drilling holes can achieve multiple uses of large-diameter drilling holes, save construction costs, quickly release gas pressure in coal seams, reduce the occurrence of gas disasters, increase coal seam permeability, improve gas extraction effects, and alleviate the stress concentration of tunnel surrounding rocks, enhance the stability of tunnel surrounding rocks, and reduce the difficulty of support, thereby further reducing the occurrence of gas disasters and roof disasters, ensuring the life safety of underground miners and safe and efficient production of coal mines.

[0014] 2) The large-diameter boreholes along the direction of the bedding in the drilling arrangement structure of the utility model can extract gas and reduce the gas pressure of the coal seam, while reducing the pressure of the mining tunnel and the surrounding rock, preventing stress concentration and relieving the pressure on the coal seam and the surrounding rock; the boreholes can also be used to implement pressure relief and permeability enhancement measures such as continued segmented hydraulic cavitation and segmented mechanical cavitation to enhance the pressure relief and extraction effect.

[0015] 3) The large-diameter horizontal boreholes in the roof of the utility model in the drilling arrangement structure can reduce the gas pressure of the coal seam and realize efficient gas extraction; the strong mining-affected area of ​​the tunnel can be depressurized in advance before mining, thereby reducing the pressure of the mining tunnel and surrounding rock and reducing the deformation of the tunnel surrounding rock; at the same time, hydraulic cavitation, hydraulic fracturing and other pressure-relief and permeability-enhancing measures can be carried out by relying on branch drilling to enhance the pressure relief effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a cross-sectional view of the arrangement and trend of the bottom drainage tunnel through-layer drainage drilling holes and the large-diameter horizontal drilling holes on the top plate in the structure of the utility model;

[0017] Figure 2 It is a top view of the arrangement and trend of the large-diameter boreholes along the bedding direction and the large-diameter horizontal boreholes on the top plate in the structure of the utility model;

[0018] Figure 3 This is a drilling arrangement diagram of the inclined cross section of the coal seam working face of the utility model structure.

[0019] In the figure, 1- mining tunnel drilling site, 2- working face cutting eye, 3- bottom pumping tunnel drilling site, 4- large diameter horizontal drilling hole in the roof, 5- bottom pumping tunnel through-layer extraction drilling hole, 6- working face lower drift, 7- working face upper drift, 8- large diameter drilling hole along the direction of the layer, 9- coal seam roof, 10- coal seam bottom, 11- branch drilling hole. DETAILED DESCRIPTION

[0020] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments.

[0021] Example: Figure 1-3 As shown, the utility model provides a rapid pressure relief and outburst elimination drilling hole arrangement structure based on large-diameter drilling holes, including a large-diameter drilling hole 8 arranged in the middle of the coal seam and located in the coal seam working face, a large-diameter horizontal drilling hole 4 and a plurality of branch drilling holes 11 arranged in the top plate 9 of the coal seam, and a bottom extraction tunnel and cross-layer extraction drilling hole 5 arranged in the bottom plate 10 of the coal seam.

[0022] like Figure 2 and Figure 3 As shown, there are multiple large-diameter boreholes 8 that are evenly distributed in the coal seam working face and are arranged parallel to the coal seam recovery tunnel. The two sides of the borehole in the length direction are the parallel lower drift 6 and the upper drift 7 of the working face, and the two sides of the borehole in the radial direction are connected with the recovery tunnel drilling site 1 and the working face cutting eye 2 respectively.

[0023] The large-diameter boreholes 8 along the strike direction can be arranged in a single layer or multiple layers according to the thickness of the coal seam. According to the geological conditions, the coal seam thickness below 5m can be arranged in one layer, and the coal seam thickness between 5m and 8m can be arranged in two layers; the diameter Ф of the large-diameter boreholes 8 along the strike direction is 193mm, the borehole spacing is 3.5m, the distance from the coal seam bottom plate 10 is 2.5m, and the hole depth matches the strike length of the coal seam working face.

[0024] After the construction of this type of drilling, the following effects can be achieved: 1. Extraction of gas; 2. Reduction of coal seam gas pressure, while reducing the surrounding rock pressure of the drift 6 below the working face and the drift 7 above the working face, to prevent stress concentration and relieve pressure on the coal seam and surrounding rock; 3. Relying on the drilling hole, continued segmented hydraulic cavitation, segmented mechanical cavitation and other pressure relief and permeability enhancement measures can be implemented to enhance the pressure relief and extraction effect.

[0025] like Figure 1 and Figure 2 As shown, one end of the large-diameter horizontal drill hole 4 in the roof is connected to the drilling site 1 of the mining tunnel, and the other end extends obliquely upward from the drilling site 1 in the mining tunnel toward the direction of the working face cutting eye 2 to the coal seam roof 9, and multiple branch drill holes 11 are evenly distributed in the upper part in the horizontal direction, and each large-diameter horizontal drill hole 4 in the roof has multiple branch drill holes 11 evenly distributed downward, and the branch drill holes 11 are connected between the large-diameter horizontal drill hole 4 in the roof and the top of the coal seam working face; the diameter Φ of the large-diameter horizontal drill hole 4 in the roof is above 193 mm, and the hole depth matches the strike length of the coal seam working face.

[0026] The large-diameter horizontal boreholes 4 and multiple branch boreholes 11 on the roof together constitute the large-diameter comb-shaped holes on the roof, and the design height of the large-diameter comb-shaped holes on the roof matches the height of the fracture zone. As a multifunctional main borehole, the comb-shaped holes on the roof can be used as pre-extraction large-diameter boreholes before the working face is advanced to achieve efficient extraction and prepare for mining and excavation. During the advancement of the working face, the main hole can directly extract gas from the fracture zone in the goaf to control the gas accumulation problem in the upper corner; at the same time, the construction of large-diameter boreholes 4 and branch holes 11 on the roof of the adjacent upper and lower chute recovery roadway can effectively reduce the high stress value and range of the high stress area of ​​the rock mass above and around the chute 6 under the working face and the chute 7 on the working face, and can transfer the stress peak to the depth of the coal body, that is, the reasonable design and construction of the large-diameter boreholes on the roof can achieve the three functions of efficient gas pre-extraction, upper corner gas control and reduction of roadway surrounding rock stress at one time.

[0027] Therefore, the drilling site 1 in the drift 7 on the coal seam working face and the drilling site 1' in the drift 6 below the working face construct large-diameter horizontal boreholes 4 on the roof 9 of the coal seam. After the boreholes are expanded, gas is pre-extracted from the coal seam. At the same time, some of the designed large-diameter horizontal boreholes 4 on the roof and the boreholes adjacent to the drift 7 on the working face can not only realize gas pre-extraction but also relieve pressure on the drift 7 on the working face. Similarly, the construction of high-position large-diameter boreholes in the drilling site 1' can effectively reduce the roof pressure at the drift 6 below the working face and the drift 7 on the working face (reduce the pressure of the tunnel and its surrounding rock) and prevent the occurrence of roof accidents.

[0028] This type of drilling construction can achieve the following effects: 1. Reduce coal seam gas pressure and achieve efficient gas extraction; 2. Unload the strong mining-affected area of ​​the tunnel in advance before mining, reduce the pressure of the mining tunnel and surrounding rock, and reduce the deformation of the tunnel surrounding rock; 3. At the same time, hydraulic cavitation, hydraulic fracturing and other pressure-relief and permeability-enhancing measures can be carried out based on the branch borehole 11 to enhance the pressure relief effect.

[0029] like Figure 3 As shown, the large-diameter boreholes 8 extending in the direction of the layer and the large-diameter horizontal boreholes 4 on the top plate are alternately distributed on the radial end surface of the boreholes.

[0030] like Figure 1 As shown, one end of the bottom extraction tunnel through-layer extraction drill hole 5 is connected to the bottom extraction tunnel drilling site 3, and the other end extends obliquely upward to the bottom of the coal seam working face.

[0031] The above-mentioned large-diameter borehole is coordinated with the bottom pumping tunnel through-layer extraction drilling hole 5, and the bottom pumping tunnel through-layer extraction drilling hole 5 is constructed toward the coal seam by utilizing the bottom pumping tunnel drilling field 3 pre-excavated on the bottom plate of the coal seam to relieve the pressure of coal seam extraction.

[0032] Construction process:

[0033] The construction process of the large-diameter borehole 8 along the bedding direction is: hole opening, hole expansion, and hole sealing.

[0034] A Ф89mm conventional drill pipe with a Ф133mm drill bit is used to drill a hole and then the drill is withdrawn after drilling for 3-5m. Then, a conventional drill pipe with a Ф193mm spiral blade wing-shaped PDC reaming drill bit is used to reamer the hole and construction is continued until the designed hole depth is reached. After the drill is withdrawn, a Ф127mm screen pipe is placed under the extraction section, and a two-blocking and one-injection sealer is used to seal the hole 20m away from the hole mouth.

[0035] The construction process of large-diameter horizontal drilling 4 of the roof is as follows:

[0036] Step 1. Use a conventional drill pipe with a 96mm PDC drill bit to drill a hole. Drill until the coal is penetrated and the rock is exposed for 1-2m before retracting the drill. Then use a 193mm spiral blade wing PDC reaming drill bit to reame the hole to the drilling position. After retracting the drill, lower a 127mm casing (the casing length is determined according to the actual length of coal penetration) into the rock section, bury the grouting pipe and the return grouting pipe, and then use sealing cement to grout the pipe. Directional drilling can be carried out only after the cement solidifies for no less than 24 hours.

[0037] Step 2. Use a directional drill to construct the main hole with a large diameter for drilling the top plate, and use a center cable drill rod equipped with a line-through drilling measurement device, a bottom hole motor, etc. to construct the main hole with a large diameter for drilling the top plate to the designed hole depth.

[0038] Step 3. After the main hole is constructed, the drill is withdrawn to the predetermined position to construct the branch hole. The branch hole is drilled until the coal is penetrated and the rock is exposed.

[0039] The drilling arrangement structure of the utility model can quickly eliminate the danger of coal seam outburst by separately constructing large-diameter boreholes along the direction of the layer and large-diameter horizontal boreholes on the top plate and their multiple branch boreholes, and cooperate with the bottom extraction tunnel through-layer holes. At the same time, it can reduce the high stress accumulated in the tunnel and surrounding rock, reduce the elastic energy in the surrounding rock, and reduce the danger of coal seam impact.

[0040] The above description is only used to illustrate the technical solution of the utility model rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the utility model by ordinary technicians in this field should be included in the scope of the claims of the utility model as long as they do not depart from the spirit and scope of the technical solution of the utility model.

Claims

1. A fast pressure relief and outburst elimination drilling arrangement structure based on large diameter drilling, characterized in that: The invention comprises a large-diameter borehole (8) arranged in the middle of a coal seam and located in the coal seam working face, a large-diameter horizontal borehole (4) arranged in the coal seam roof (9) and its branch boreholes (11), and a bottom extraction tunnel through-layer extraction borehole (5) arranged in the coal seam bottom plate (10); a plurality of large-diameter boreholes (8) arranged in the coal seam working face are evenly distributed at intervals and are arranged in parallel with the coal seam recovery tunnel, and the two sides of the borehole in the longitudinal direction are respectively parallel to the working face lower drift (6) and the working face drift (7), and the two sides of the borehole in the radial direction are respectively parallel to the recovery tunnel drilling site (1) and the working face cutting site (1). The large-diameter horizontal borehole (4) of the roof is connected to the eye (2); one end of the large-diameter horizontal borehole (4) of the roof is connected to the drilling site (1) of the mining tunnel, and the other end extends obliquely upward from the mining tunnel drilling site (1) to the direction of the working face cutting eye (2) into the coal seam roof (9), and a plurality of branch boreholes (11) are evenly distributed in the upper part in the horizontal direction, and each large-diameter horizontal borehole (4) of the roof is evenly distributed downwardly with a plurality of branch boreholes (11), and the branch boreholes (11) are connected between the large-diameter horizontal borehole (4) of the roof and the top of the coal seam working face; one end of the bottom extraction tunnel through-layer extraction borehole (5) is connected to the drilling site (3) of the bottom extraction tunnel, and the other end extends obliquely upward to the bottom of the coal seam working face.

2. According to claim 1, a fast pressure relief and outburst elimination drilling arrangement structure based on large diameter drilling is characterized by: The large-diameter horizontal drill holes (4) on the top plate and the plurality of branch drill holes (11) together constitute large-diameter comb-shaped holes on the top plate, and the design height of the large-diameter comb-shaped holes on the top plate matches the height of the fracture zone.

3. A fast pressure relief and outburst elimination drilling arrangement structure based on large diameter drilling according to claim 1 or 2, characterized in that: The large-diameter boreholes (8) extending in the direction of the layer and the large-diameter horizontal boreholes (4) on the top plate are distributed alternately on the radial end faces of the boreholes.

4. The fast pressure relief and outburst elimination drilling arrangement structure based on large diameter drilling according to claim 1 is characterized in that: The large-diameter boreholes (8) along the strike direction are arranged in at least one layer, and a coal seam thickness of less than 5 m is arranged in one layer, and a coal seam thickness of 5 m to 8 m is arranged in two layers.

5. A fast pressure relief and outburst elimination drilling arrangement structure based on large diameter drilling according to claim 1 or 4, characterized in that: The design diameter Φ of the large-diameter borehole (8) along the strike of the coal seam is 193 mm, the borehole spacing is 3.5 m, the distance from the coal seam bottom plate (10) is 2.5 m, and the hole depth matches the strike length of the coal seam working face.

6. The fast pressure relief and outburst elimination drilling arrangement structure based on large diameter drilling according to claim 1 is characterized in that: The design diameter Φ of the large-diameter horizontal drill hole (4) in the roof is greater than 193 mm, and the hole depth matches the strike length of the coal seam working face.

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