A multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method

Abstract

The present invention relates to a multi-hazard directional long borehole single-hole multi-effect active regional collaborative prevention and control method, the method comprising: determining a disaster control layer, the disaster control layer comprising: a water hazard control rock layer, a strong mine pressure or rock burst disaster control rock layer, a triangular area suspended roof control layer and a spontaneous combustion disaster control coal seam; determining the main hole layout layer of the fracturing borehole; arranging a double comb borehole according to the main hole layout layer, and the upward branch hole of the double comb borehole extends upward to the disaster control layer located at the top, and the downward branch hole extends downward to the spontaneous combustion disaster control coal seam; constructing the double comb borehole; after the construction of the double comb borehole is completed, the fracturing equipment is transported to the double comb borehole for layered and zoned fracturing. The method can avoid the mutual influence of different governance methods, realize the coordinated source governance of multi-hazard coupling, and reduce the governance cost.

Description

Technical Field

[0001] The invention relates to the technical field of underground coal mine safety, and in particular to a multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method. Background Art

[0002] With the continuous improvement of my country's coal mining equipment and technology and the improvement of the safety supervision system, coal mine accidents have been effectively controlled, and the number of accidents and deaths has decreased year by year. However, in the process of coal mine production, roof accidents, water damage, gas extraction left in goafs, and poor top coal venting in thick and hard coal seams, which waste resources and easily cause gas accumulation and spontaneous combustion, are still difficult problems in the prevention and control of mine safety production, and most mines have multiple disasters.

[0003] The existing prevention and control technologies are basically targeted and classified prevention and control of single disasters. The amount of governance projects is large, and the disaster prevention and control projects interfere with each other, which greatly reduces the disaster prevention and control effect. In addition, the implementation cycle of prevention and control measures is long, which restricts the continuation of mine excavation. The present invention proposes a multi-disaster directional long drilling single-hole multi-effect active regional collaborative prevention and control technology to carry out collaborative and effective governance of multiple disasters in mines and ensure safe and efficient production of coal mines. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method.

[0005] To solve the above problems, the technical solution adopted by the present invention is:

[0006] A multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method, comprising:

[0007] Determine the disaster control layer, which includes: water hazard control rock layer, strong mine pressure or rock burst disaster control rock layer, triangle area hanging roof control layer and spontaneous combustion disaster control coal seam;

[0008] Determine the main hole layout layer of the fracturing drilling;

[0009] Arrange double comb-shaped boreholes according to the main hole arrangement layer, and the upward branch holes of the double comb-shaped boreholes extend upward to the disaster control layer located at the top, and the downward branch holes extend downward to the spontaneous combustion disaster control coal seam;

[0010] constructing the double comb borehole;

[0011] After the double-comb drilling construction is completed, the fracturing equipment is transported into the double-comb drilling hole to perform layered and zoned fracturing.

[0012] As an implementation mode of the invention, determining the disaster control layer includes:

[0013] Determine the water hazard control rock layer based on the mine hydrogeological report and geophysical data, and obtain the distance H between the bottom of the water hazard control rock layer and the coal seam. A ;

[0014] According to the collapse of the triangular area of ​​the goaf during the mining process, the strong mine pressure or rock burst disaster control rock layer of the hard roof is determined in combination with the coal seam geological columnar data, and the distance H between the bottom of the strong mine pressure or rock burst disaster control rock layer and the coal seam is obtained. B , and the thickness of the water hazard control rock layer h B ;

[0015] According to coal seam mining, determine the triangular area hanging roof control layer, and obtain the distance H between the bottom of the triangular area hanging roof control layer and the coal seam C , and the thickness of the triangular area overhang control layer h C ;

[0016] The coal seam controlled by spontaneous combustion disaster is determined based on the identification results of the coal seam spontaneous combustion tendency and mechanical parameters.

[0017] As an embodiment of the invention, the method of determining the strong mining pressure or rock burst disaster control rock layer of the hard roof according to geological survey data includes:

[0018] Obtain the thickness, bulk density and elastic modulus of each rock layer based on geological survey data;

[0019] Calculate from the first layer above the coal seam upwards layer by layer, and take each rock layer as the rock layer to be calculated in turn. When it is determined that the mth layer to be calculated satisfies the following formula, take the m+1th layer as the first hard rock layer; starting from the m+1th layer, continue to calculate upwards layer by layer according to the following calculation formula to obtain all n layers of hard rock layers that meet the following formula;

[0020]

[0021] Among them, h i , γ i , E i are the thickness, bulk density and elastic modulus of the ith rock layer (i=1,2,…,m).

[0022] Based on the microseismic monitoring data of the mining face, the strong mining pressure or impact ground pressure disaster control layer in the hard rock layer is determined.

[0023] As an embodiment of the invention, the following formula is used to obtain the average energy e of microseismic events in each hard rock layer: i :e i =∑e j ÷x; where e i is the average energy of the microseismic event in the i-th hard rock layer (i=1,2,…,n), x is the number of microseismic events, ej is the energy of a single microseismic event (j=1,2,…,x);

[0024] The maximum average energy of microseismic events is determined, and the hard rock layer corresponding to the maximum average energy of microseismic time is used as the control layer for strong mining pressure or rock burst disasters.

[0025] As an embodiment of the invention, determining the main hole layout layer of the fracturing borehole includes:

[0026] When H A is min(H A , H B , H C ), the main hole is arranged at the lower boundary of the water hazard control rock layer, and the layer position of the main hole is H 主 Satisfy the formula: H A <H 主 <H A +0.5m.

[0027] As an embodiment of the invention, the determination of the main hole arrangement layer of the fracturing borehole further includes:

[0028] When H A＞ min(H A , H B , H C ), the main hole is arranged in the layer below the water hazard control rock layer and adjacent to the disaster control layer, and the layer of the main hole H 主 Satisfy the formula:

[0029] H 主 =max(H B , H C )+0.5h max(B，C) , where h max(B，C) It is the thickness of the adjacent disaster control layer below the main water hazard control layer.

[0030] As an embodiment of the invention, the distance L between any two adjacent branch holes in the double comb borehole is the fracturing radius r 压 twice as much.

[0031] As an embodiment of the invention, after the double-comb drilling is completed, the fracturing equipment is transported into the double-comb drilling to perform layered and zoned fracturing, including:

[0032] Add proppant to the water hazard control rock formation for fracturing construction;

[0033] Add high viscosity fracturing fluid to perform fracturing construction in rock formations with strong mining pressure or rock burst disaster control;

[0034] Carry out directional controlled-scale and extremely close-range spraying construction with abrasive in the suspended top control layer of the triangle area;

[0035] Directional injection and addition of flame-retardant fracturing fluid are used in coal seams to control spontaneous combustion hazards.

[0036] As an embodiment of the invention, the method further includes: extracting coal seam gas and goaf gas through the double-comb drill holes.

[0037] The beneficial effects of adopting the above technical solution are:

[0038] The multi-hazard directional long drilling single-hole multi-effect active regional collaborative prevention and control method provided by the present invention realizes single-hole multi-effect, reduces ineffective drilling footage, improves drilling utilization, shortens construction period, avoids mutual influence of different control methods, realizes multi-hazard coupling collaborative source control, and reduces control costs.

[0039] In addition, the advanced control boreholes that have been formed to connect the roof and the coal seam can be used as coal seam gas and goaf gas extraction channels, thereby solving the problem of difficulty in coal seam and goaf gas extraction. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a flow chart of a multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method provided by the present invention.

[0041] Figure 2 It is a schematic diagram of a disaster control layer provided by the present invention.

[0042] Figure 3 It is a schematic diagram of another disaster control layer provided by the present invention.

[0043] Figure 4 This is a schematic diagram of the management scope of another disaster control layer provided by the present invention.

[0044] Among them: 1-water hazard control rock layer, 2-strong mining pressure or impact rock pressure disaster control rock layer, 3-triangular area hanging roof control layer, 4-spontaneous combustion disaster control coal seam, 5-control scope. DETAILED DESCRIPTION

[0045] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is clearly and completely described below in conjunction with specific embodiments.

[0046] The present invention provides a multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method, such as Figure 1 As shown, the method includes:

[0047] Step S1, determining the disaster control layer, wherein the disaster control layer includes: water hazard control rock layer, strong mine pressure or rock burst disaster control rock layer, triangle area hanging roof control layer and spontaneous combustion disaster control coal seam.

[0048] The methods for determining the above four disaster control layers mainly include:

[0049] Step S101: Determine the water hazard control rock layer according to the mine hydrogeological report and geophysical data, and obtain the distance H between the bottom of the water hazard control rock layer and the coal seam. A .

[0050] The mine hydrogeological report and geophysical data will indicate that the layer belongs to the water hazard control rock layer, and the staff can also obtain H A , the embodiments of the present invention will not be described in detail.

[0051] It should be noted that the coal seam refers to the mined coal seam. When the coal seam is a spontaneous combustion disaster controlled coal seam, the coal seam is a spontaneous combustion disaster controlled coal seam.

[0052] Step S102: Determine the strong mine pressure or rock burst disaster control rock layer of the hard roof according to the geological survey data, and obtain the distance H between the bottom of the strong mine pressure or rock burst disaster control rock layer and the coal seam. B , and the thickness of the water hazard control rock layer h B .

[0053] The steps of determining the strong mine pressure or rock burst disaster control rock layer of the hard roof according to the geological survey data include:

[0054] Step S1021, obtaining the thickness, bulk density and elastic modulus of each rock layer according to geological survey data;

[0055] Calculate from the first layer above the coal seam upwards layer by layer, and take each rock layer as the rock layer to be calculated in turn. When it is determined that the mth layer to be calculated satisfies the following formula, take the m+1th layer as the first hard rock layer; starting from the m+1th layer, continue to calculate upwards layer by layer according to the following calculation formula to obtain all n layers of hard rock layers that meet the following formula;

[0056]

[0057] Among them, h i , γ i , E i are the thickness, bulk density and elastic modulus of the i-th rock layer (i=1,2,…,m);

[0058] Step S1022: Determine the strong mining pressure or rock burst disaster control layer in the hard rock layer based on the microseismic monitoring data of the miner's working face.

[0059] Specifically, the following formula is used to obtain the average energy of microseismic events in each hard rock layer: i :e i =∑e j÷x; where e i is the average energy of the microseismic event in the i-th hard rock layer (i=1,2,…,n), x is the number of microseismic events, e j is the energy of a single microseismic event (j=1,2,…,x);

[0060] Determine the maximum average energy of microseismic events e M =max(e1, e2, ..., e n ), the maximum shock time average energy e M The corresponding hard rock layer serves as a control layer for strong mining pressure or rock burst disasters.

[0061] Of course, if there are two or more identical values ​​for the maximum microseismic event average energy, the hard rock layer corresponding to the average energy of all microseismic times corresponding to the value will be used as the strong mining pressure or rock burst disaster control layer.

[0062] After obtaining the strong mine pressure or rock burst disaster control rock layer, the total thickness of the rock layer contained in the strong mine pressure or rock burst disaster control rock layer is taken as the thickness of the strong mine pressure or rock burst disaster control rock layer h B The minimum distance between the lowest rock layer and the coal seam in the rock layer controlled by strong mining pressure or rock burst disaster is taken as H B .

[0063] Step S103: According to the collapse of the triangular area of ​​the goaf during the mining process, the triangular area hanging roof control layer is determined in combination with the coal seam geological columnar data, and the distance H between the bottom of the triangular area hanging roof control layer and the coal seam is obtained. C , and the thickness of the triangular area overhang control layer h C ;

[0064] Step S104: Determine the spontaneous combustion disaster controlled coal seam according to the spontaneous combustion tendency identification result or mechanical parameters of the coal seam. The spontaneous combustion tendency identification result shows whether the coal seam is a spontaneous combustion disaster controlled coal seam, and the staff can determine whether the current coal seam is a spontaneous combustion disaster controlled coal seam based on this.

[0065] Step S2: determine the main hole layout layer of the fracturing borehole.

[0066] In the present invention, according to the different distances between each disaster control layer and the coal seam, two methods are provided to determine the layer position for arranging the main holes.

[0067] Method 1: Figure 2 As shown, when H A is min(H A , H B , H C ), the main hole is arranged at the lower boundary of the water hazard control rock layer, and the layer position of the main hole is H 主 Satisfy the formula: HA <H 主 <H A +0.5m.

[0068] Method 2: Figure 3 As shown, when H A＞ min(H A , H B , H C ), the main hole is arranged in the layer below the water hazard control rock layer and adjacent to the disaster control layer, and the layer of the main hole H 主 Satisfy the formula:

[0069] H 主 =max(H B , H C )+0.5h max(B，C) , where h max(B，C) It is the thickness of the adjacent disaster control layer below the main water hazard control layer.

[0070] Step S3, arranging double comb drill holes according to the main hole arrangement layer.

[0071] Among them, the upward branch holes of the double-comb drill holes extend upward to the disaster control layer at the top, and the downward branch holes extend downward to the spontaneous combustion disaster control coal seam.

[0072] The double comb type includes a main hole, several upward branch holes, and several downward branch holes. The distance L between any two adjacent upward branch holes is the fracturing radius r. 压 Similarly, the distance L between any two adjacent downward branch holes is also equal to the fracturing radius r. 压 Among them, for different disaster control layers, the fracturing radius r 压 It can be determined by the staff according to the geological parameters and mining parameters of the mining process. The determination method is commonly used by those skilled in the art, and the embodiments of the present invention will not be described in detail here.

[0073] The length of the main hole, the number of the upward branch holes and the downward branch holes can be determined according to actual needs, and the embodiment of the present invention does not specifically limit this.

[0074] Step S4, constructing the double comb-shaped drilling holes.

[0075] The construction method may be that disclosed in the prior art, and the embodiments of the present invention are not limited thereto.

[0076] Step S5: After the double-comb drilling is completed, the fracturing equipment is transported into the double-comb drilling to perform layered and zoned fracturing.

[0077] In the present invention, different prevention and control measures are implemented for different disaster control layers. In a possible implementation, Figure 4As shown, the details are as follows:

[0078] ① Regarding the water hazard control rock layer, which is mainly the water-rich sandstone layer, proppant is added in the layer for fracturing construction to form artificial fracture drainage channels, which greatly improves the drainage efficiency and shortens the drainage cycle.

[0079] ② For strong mining pressure or rock burst disaster control rock strata, the main problem is that the thick layer of hard sandstone roof causes strong mining pressure or rock burst dynamic disasters. Therefore, high-viscosity fracturing fluid is added to the layer for fracturing construction to form a three-dimensional crack network, which effectively reduces the strength of the rock mass and destroys the integrity of the rock mass, achieving the purpose of advanced prevention and control of strong mining pressure or rock burst dynamic disasters.

[0080] ③ Aiming at the triangular area hanging roof control layer, which is mainly the triangular area hanging roof problem existing in the mining process, abrasive directional controlled scale extremely close distance spraying is carried out in this layer to form an artificial fracture line, and the fracture line scale is expanded through hydraulic fracturing to achieve the effect of the triangular area roof falling as it is mined;

[0081] ④ For the control of spontaneous combustion disasters in coal seams, the main problems are: the coal seams are thick and hard, the top coal has poor caving performance during comprehensive caving mining, it is difficult to caving, there is a large waste of resources, and the coal body is prone to spontaneous combustion. Directional injection and addition of flame-retardant fracturing fluid in this layer, through the use of directional injection and flame-retardant fracturing fluid fracturing, the coal body is effectively weakened while curbing spontaneous combustion of the coal body.

[0082] In addition, the present invention adopts layered and zoned segmented fracturing. After the fracturing of the current area is completed, backwashing is performed to ensure that the inside of the pump group is clean before fracturing the next area.

[0083] The method provided by the embodiment of the present invention realizes multiple effects of a single hole, reduces ineffective drilling footage, improves drilling utilization, shortens construction period, avoids mutual influence of different control methods, realizes coordinated source control of multiple disaster coupling, and reduces control costs.

[0084] Furthermore, after the fracturing is completed, it may also include step S6, extracting coal seam gas and goaf gas through the double comb boreholes.

[0085] Specifically, the advanced control boreholes that have been formed to connect the roof and coal seam can be used as coal seam gas and goaf gas extraction channels, thereby solving the problem of difficulty in coal seam and goaf gas extraction, preventing and controlling gas disasters, further increasing the prevention and control areas, and achieving multi-region coordinated prevention and control effects.

Claims

1. A multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method, characterized in that: Methods include: Determine the disaster control layer, which includes: water hazard control rock layer, strong mine pressure or rock burst disaster control rock layer, triangle area hanging roof control layer and spontaneous combustion disaster control coal seam; Determine the main hole layout layer of the fracturing drilling; Arrange double comb-shaped boreholes according to the main hole arrangement layer, and the upward branch holes of the double comb-shaped boreholes extend upward to the disaster control layer located at the top, and the downward branch holes extend downward to the spontaneous combustion disaster control coal seam; constructing the double comb borehole; After the double-comb drilling construction is completed, the fracturing equipment is transported into the double-comb drilling hole to perform layered and zoned fracturing.

2. The multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method according to claim 1 is characterized in that: Determining the disaster control layer includes: Determine the water hazard control rock layer based on the mine hydrogeological report and geophysical data, and obtain the distance H between the bottom of the water hazard control rock layer and the coal seam. A ; According to the geological survey data and geophysical exploration data, determine the strong mining pressure or rock burst disaster control rock layer of the hard roof, and obtain the distance H between the bottom of the strong mining pressure or rock burst disaster control rock layer and the coal seam. B , and the thickness of the water hazard control rock layer h B ; According to the collapse of the triangular area of ​​the goaf during mining, the triangular area hanging roof control layer is determined in combination with the geological columnar data of the coal seam, and the distance H between the bottom of the triangular area hanging roof control layer and the coal seam is obtained. C , and the thickness of the triangular region overhang control layer h C ; Determine the spontaneous combustion disaster control coal seam based on the spontaneous combustion tendency identification results or mechanical parameters of the coal seam.

3. The multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method according to claim 2 is characterized in that: The method of determining the strong mining pressure or rock burst disaster control rock layer of the hard roof based on geological survey data and geophysical exploration data includes: Obtain the thickness, bulk density and elastic modulus of each rock layer based on geological survey data; Calculate from the first layer above the coal seam upwards layer by layer, and take each rock layer as the rock layer to be calculated in turn. When it is determined that the mth layer to be calculated satisfies the following formula, take the m+1th layer as the first hard rock layer; starting from the m+1th layer, continue to calculate upwards layer by layer according to the following calculation formula to obtain all n layers of hard rock layers that meet the following formula; Among them, h i , γ i , E i are the thickness, bulk density and elastic modulus of the i-th rock layer (i=1,2,…,m); Based on the microseismic monitoring data of the mining face, the strong mining pressure or impact ground pressure disaster control layer in the hard rock layer is determined.

4. The multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method according to claim 3 is characterized in that: The control layer of strong mining pressure or rock burst disaster in the hard rock layer is determined based on the microseismic monitoring data of the mining face that has been mined by the mine, including: The average energy of microseismic events in each hard rock layer is obtained using the following formula: i :e i =∑e j ÷x; where e i is the average energy of the microseismic event in the i-th hard rock layer (i=1,2,…,n), x is the number of microseismic events, e j is the energy of a single microseismic event (j=1,2,…,x); The maximum average energy of microseismic events is determined, and the hard rock layer corresponding to the maximum average energy of microseismic time is used as the control layer for strong mining pressure or rock burst disasters.

5. The multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method according to claim 2 is characterized in that: Determining the main hole layout layer of the fracturing borehole includes: When H A is min(H A , H B , H C ), the main hole is arranged at the lower boundary of the water hazard control rock layer, and the layer position of the main hole is H 主 Satisfy the formula: H A <H 主 <H A +0.5m.

6. A multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method according to claim 5, characterized in that: Determining the main hole layout of the fracturing borehole also includes: When H A＞ min(H A , H B , H C ), the main hole is arranged in the layer below the water hazard control rock layer and adjacent to the disaster control layer, and the layer of the main hole H 主 Satisfy the formula: H 主 =max(H B , H C )+0.5h max(B，C) , where h max(B，C) It is the thickness of the adjacent disaster control layer below the main water hazard control layer.

7. The multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method according to claim 1 is characterized in that: The distance L between any two adjacent branch holes in the double comb borehole is the fracturing radius r 压 twice.

8. The multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method according to claim 1 is characterized in that: After the double comb drilling is completed, the fracturing equipment is transported into the double comb drilling to perform layered and zoned fracturing, including: Add proppant to the water hazard control rock formation for fracturing construction; Add high viscosity fracturing fluid to perform fracturing construction in rock formations with strong mining pressure or rock burst disaster control; Carry out directional controlled-scale and extremely close-range jetting construction with abrasive in the suspended top control layer of the triangle area; Directional injection and addition of flame-retardant fracturing fluid are used in coal seams to control spontaneous combustion hazards.

9. The multi-hazard directional long drilling single-hole multi-effect active regional coordinated prevention and control method according to claim 1 is characterized in that: The method further comprises: extracting coal seam gas and goaf gas through the double comb-shaped drilling holes to prevent and control gas disasters.

Images