Integrated drilling implementation method for extraction and pressure relief in coal-rock gas hybrid dynamic disasters

Abstract

The invention relates to the field of coal rock gas composite disaster prevention and control, in particular to a coal rock gas composite dynamic disaster first extraction and second pressure relief integrated drilling implementation method which comprises the following steps: judging a composite disaster dangerous area; bedding drilling is carried out on the coal seam needing gas extraction and rock burst disaster prevention and control; the drill bit retreats after construction to the designed depth; grouting the hole sealing section outside the pipe and inside the pipe; a gas drainage pump is connected for gas drainage; and after gas extraction is completed, the drill hole sealing section is extracted out, and gas extraction drill holes are changed into pressure relief drill holes. The drilled hole constructed through the method achieves multiple purposes through partitioning, and gas and rock burst disasters are jointly prevented and controlled.

Description

Technical Field

[0001] The invention relates to the field of prevention and control of coal and gas composite disasters, and in particular to an integrated drilling implementation method for coal, rock and gas composite dynamic disasters, which includes extraction followed by pressure relief. Background Art

[0002] The causative factors, occurrence mechanisms and coupling relationships of coal-rock gas compound dynamic disasters are complex and diverse, and it is necessary to comprehensively consider multiple factors to formulate effective prevention and control measures. The possibility of disasters can be effectively reduced by changing the physical and mechanical properties of coal and rock mass, reducing coal and rock mass stress, reducing gas pressure, and increasing the bearing strength of tunnel surrounding rock.

[0003] In view of this, the present invention proposes an integrated drilling implementation method for coal-rock gas composite dynamic disasters, which first extracts and then relieves pressure, and solves the above-mentioned technical problems. Summary of the invention

[0004] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0005] The present invention proposes a method for implementing a one-piece drilling hole for coal-rock gas composite dynamic disasters, which involves first extraction and then pressure relief: this method combines the pressure relief drilling hole with the gas extraction drilling hole into one, and through one drilling hole, both coal body pressure relief and gas extraction can be performed, thus achieving "one hole for multiple uses", reducing the cost of disaster prevention and control and alleviating the labor burden.

[0006] A method for implementing a coal-rock gas composite power disaster by first extracting and then unloading the integrated drilling hole, comprising the following steps: S1: Determine the complex disaster hazard area based on rock burst, gas disaster risk assessment and actual monitoring data of the mine and other influencing factors, and clarify the drilling construction parameters; S2: Carry out drilling construction in this coal seam according to the complex disaster risk area determined in S1; S3: When the gas extraction task in this area is completed, the sealing section of the gas extraction borehole is extracted to complete the conversion of the gas extraction borehole to the pressure relief borehole.

[0007] Preferably, the influencing factors for evaluating the composite disaster risk area in S1 are: Factors affecting gas disasters include: coal seam thickness, coal seam inclination, coal solidity coefficient, roof and floor lithology, gas pressure, coal seam gas content, initial velocity of gas outflow from drilling holes, and gas desorption index of drill cuttings; The factors affecting rock burst disasters include: multi-factor coupling method, comprehensive index method and factors mentioned in impact tendency identification.

[0008] Preferably, in the gas extraction drilling construction of S2, the entire sealing section is formed by splicing the inner and outer sealing pipe sections, and after the splicing is completed, grouting is injected into the inner and outer pipes respectively to complete the sealing.

[0009] Preferably, the S3 gas extraction borehole is converted into a pressure relief borehole, and when the gas extraction work is completed, the filling in the pipe is pulled out through the pre-buried threaded steel bars in the sealing section and the far-end tray, thereby completing the borehole conversion.

[0010] Beneficial effects of the present invention: This invention combines the prevention and control concepts of rock burst disasters and gas disasters, and proposes a method for preventing and controlling coal-rock gas composite disasters based on coal seam drilling: this method combines the pressure relief drilling hole and the gas extraction drilling hole into one, and through one drilling hole, both gas extraction and coal body pressure relief can be achieved, realizing "one hole for multiple uses", reducing disaster prevention and control costs, and alleviating the labor burden. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0012] in: Figure 1 This is a schematic diagram of the integrated drilling method of first extraction and then pressure relief for coal-rock gas composite power disasters of the present invention; Figure 2 It is a cross-sectional view of the drilling and sealing section of the present invention.

[0013] In the figure: 1-coal seam borehole wall; 2-grouting bag; 3-prefabricated borehole plug outer tube; 4-threaded steel bar; 5-remote end tray; 6-prefabricated borehole plug inner tube; 7-gas extraction screen; 8-prefabricated borehole plug filling part; 9-prefabricated pipe joint; 10-borehole pressure relief section. DETAILED DESCRIPTION

[0014] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] The present invention aims to provide an integrated drilling method for extracting first and then relieving pressure in case of coal-rock gas composite dynamic disaster, aiming to provide a method for constructing a single borehole to alleviate the composite disaster of coal seam rock pressure and gas.

[0016] The present invention provides a method for implementing a coal-rock gas composite power disaster integrated drilling method of first extraction and then pressure relief, comprising the following steps: S1: Determine the complex disaster risk area based on impact rock pressure, gas disaster risk assessment, and actual monitoring data of the mine, and clarify the drilling construction parameters.

[0017] S2: Carry out drilling construction in this coal seam according to the complex disaster risk areas determined in S1.

[0018] S3: When the gas extraction task in this area is completed, the sealing section of the gas extraction borehole is extracted to complete the conversion of the gas extraction borehole to the pressure relief borehole.

[0019] The influencing factors for evaluating complex disaster risk areas are:

[0020] Factors affecting gas disasters include: coal seam thickness, coal seam inclination, coal solidity coefficient, roof and floor lithology, gas pressure, coal seam gas content, initial velocity of gas outflow from drilling holes, and gas desorption index of drill cuttings; Factors affecting gas disasters include: coal seam thickness, coal seam inclination, coal solidity coefficient, roof and floor lithology, gas pressure, coal seam gas content, initial velocity of gas outflow from drilling holes, and gas desorption index of drill cuttings; The drilling construction parameters in S1 include: drilling hole diameter, hole spacing, drilling construction length, and sealing hole length; After the drilling construction in S2 reaches the designed length, the coal and rock powder in the hole is flushed clean with compressed air, and the sealing splicing pipe is placed in the sealing position, and threaded steel bars are built in. The "two blocking and one injection" filling method is adopted between the outside of the pipe and the borehole wall. When sealing the hole, the sealing pump grouting pipe is connected to the bag sealer to start grouting. The explosion valves inside the inner and outer bags have been modified. After being subjected to pressure, the explosion valves start to open, and the bags inside and outside the sealer are filled first. After the bags are filled, due to pressure reasons, the explosion valve in the sealing section opens, and cement slurry begins to be injected into the sealing section along the grouting pipe, and the air in the sealing section is discharged along the air guide pipe. When cement slurry flows out of the air guide pipe, it means that the sealing is completed.

[0021] After the hole is sealed in S3, gas extraction is carried out until the gas extraction work is completed and the working face is about to be mined. The filling parts of the inner and outer pipes of the gas sealing section are extracted through the pre-buried threaded steel bars.

[0022] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0023] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for implementing integrated drilling of coal-rock gas composite power disasters by first extracting and then unloading pressure, characterized in that: The following steps are involved: S1: Determine the complex disaster hazard area based on rock burst, gas disaster risk assessment and actual monitoring data of the mine and other influencing factors, and clarify the drilling construction parameters; S2: Carry out drilling construction in this coal seam according to the complex disaster risk area determined in S1; S3: When the gas extraction task in this area is completed, the sealing section of the gas extraction borehole is extracted to complete the conversion of the gas extraction borehole to the pressure relief borehole.

2. The integrated drilling method for coal-rock gas composite power disaster extraction followed by pressure relief according to claim 1 is characterized in that: The influencing factors for evaluating the composite disaster risk area in S1 are: Factors affecting gas disasters include: coal seam thickness, coal seam inclination, coal solidity coefficient, roof and floor lithology, gas pressure, coal seam gas content, initial velocity of gas outflow from drilling holes, and gas desorption index of drill cuttings; The factors affecting rock burst disasters include: multi-factor coupling method, comprehensive index method and factors mentioned in impact tendency identification.

3. The integrated drilling method for coal-rock gas composite power disaster extraction followed by pressure relief according to claim 1 is characterized in that: In the gas extraction drilling construction of S2, the entire sealing section is spliced ​​by the inner and outer sealing pipe sections. After the splicing is completed, grouting is injected into the inner and outer pipes respectively to complete the sealing.

4. The integrated drilling method for coal-rock gas composite power disaster extraction followed by pressure relief according to claim 1 is characterized in that: The S3 gas extraction borehole is transformed into a pressure relief borehole. When the gas extraction work is completed, the filling in the pipe is pulled out through the pre-buried threaded steel bars in the sealing section and the far-end tray, thereby completing the borehole conversion.

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