CN104879128A - Steep-dip ultra-thick coalbed mining technique based on top-coal advancing pre-detonation weakening - Google Patents

Abstract

The invention discloses a coal mining technology for steeply inclined and extra-thick coal seams based on advanced pre-explosion weakening. The steeply inclined and extra-thick coal seam is mined in a plurality of mining segments from back to front along the coal seam direction. When mining, the process is as follows: 1. Roadway construction; 2. Top coal advance pre-explosion weakening, the process is as follows: 201. Determination of the coal seam to be blasted; 204, blasting for the first time; 205, blasting for the second time; 3. coal seam mining; 4. mining in the next mining segment; The entire mining process of thick coal seams. The invention has simple process steps, reasonable design, high mining efficiency, high recovery rate of the working face, and good use effect, and can solve the complex process, low recovery rate of the working face, many safety hazards, and low mining efficiency existing in the existing coal mining process. question.

Description

Coal mining technology of steeply inclined and extra-thick coal seam based on weakening of top-coal pre-explosion

technical field

The invention relates to a coal mining process, in particular to a coal mining process for a steeply inclined extra-thick coal seam based on the weakening of top coal advance pre-explosion.

Background technique

The top-coal caving mining method is to arrange a coal mining face with a mining height of 2m to 3m along the floor of the coal seam or the bottom of a certain thickness range of the coal seam when mining a thick coal seam. After the top coal is broken into loose bodies, it is discharged from the "coal discharge window" behind or above the support, and is transported out of the working face by a scraper conveyor. Combining Figure 1-1 and Figure 1-2, when mining steeply inclined extra-thick coal seams (coal seams with a coal seam dip angle of more than 45° and a coal seam thickness of more than 8m), the coal mining technology adopted is as follows: First, the coal mining face 1-1 Stop the production, and use the rock electric drill to drill holes above the working face support 1; after that, manually use the gun stick to fill the emulsion explosive, and use the gun stick to artificially seal the hole; then, detonate and blast; finally, wait for the blasting After the smoke dissipates, the working face resumes coal mining and coal discharge, so that a coal mining cycle is completed, and the coal mining face 1-1 advances forward, where the coal mining face 1-1 adopts the coal mining machine 1-2 Then, complete the next coal mining work cycle according to the above-mentioned procedures of drilling, charging, sealing, blasting, coal mining and coal discharge. However, when the existing coal mining technology is used for caving mining, usually two rows of blastholes are arranged in the front and rear of the coal mining face, and each row of blastholes includes a plurality of blastholes arranged from left to right. They are respectively the front row of blastholes 2-1 and the rear row of blastholes 2-2 located at the rear side of the front row of blastholes, wherein the rear row of blastholes 2-2 is located above the working surface support 1, and the front row of blastholes 2-1 is located on the working surface support Above the front side of 1; emulsion explosives are used in each blast hole, and the charge structure adopts reverse charge. Six sections of large charges form a group, with one section of priming charge, each section of priming charge contains a detonator, and the priming charge detonator line It is connected in parallel; the hole is sealed with loess rolls of the same specification as the charge rolls; in actual detonation, every 3 blastholes are detonated in series from left to right. In the actual construction process, the above coal mining process has the following problems: first, the recovery rate of the working face is low, there are many safety hazards, and the loss of coal resources is large; second, the production process is complicated, and the continuity and speed of production cannot be guaranteed; 3. The production process has not been fully mechanized, and the operating efficiency is low.

Contents of the invention

The technical problem to be solved by the present invention is to provide a coal mining process for steeply inclined and extra-thick coal seams based on the weakening of top-coal advance pre-explosion, which has simple process steps, reasonable design, high mining efficiency, and The face recovery rate is high and the use effect is good, which can solve the problems existing in the existing coal mining technology such as complex process, low recovery rate of the working face, many safety hazards, and low mining efficiency.

In order to solve the above-mentioned technical problems, the technical solution adopted in the present invention is: a kind of steeply inclined extra-thick coal seam coal mining process based on the weakening of the top-coal advance pre-explosion, the steeply inclined extra-thick coal seam mined is a coal seam dip angle of more than 45 ° and the thickness of the coal seam The coal seam above 8m is characterized in that: the steeply inclined extra-thick coal seam is mined in a plurality of mining sections from back to front along the coal seam trend, and the mining methods of the multiple mining sections are the same and they are mined along the coal seam trend. The length above is L, wherein L=30m～50m; When mining a mining segment of the steeply inclined extra-thick coal seam, the process is as follows:

Step 1, roadway construction: a ventilation roadway is constructed on the left and right sides of the lower part of the current mining section, and the two ventilation roadways are respectively the air inlet lane and the air return lane;

Step 2. Top-coal advanced pre-explosion weakening: The current mining segment is subjected to top-coal advanced pre-explosion weakening, the process is as follows:

Step 201, Determining the coal seam to be blasted: according to the thickness of the roof protection coal seam and the mining height of the working face designed in advance during the recovery process of the current mining segment, determine the top and bottom heights of the coal seam to be blasted in the current mining segment;

The top coal above the mining face of the current mining section is divided into three coal seams from bottom to top, the coal seam to be blasted, and the coal seam to be blasted, and the coal seam to be blasted is located between the coal seam to be blasted and the coal seam to be protected on the working face; Among them, the mining face of the current mining segment is the current mining face;

Step 202, Blast hole drilling: first select multiple blasting faces on the coal seam to be blasted in front of the current mining face along the advancing direction of the working face. The direction is a vertically arranged plane, and the distance between two adjacent blasting surfaces is 3m to 5m; the multiple blasting surfaces include multiple first blasting surfaces and multiple second blasting surfaces, and the first blasting surfaces The surface and the second blasting surface are arranged in a staggered manner; then, using a drilling rig to drill a plurality of first blastholes on each of the first blasting surfaces from the back to the front from the air inlet lane constructed in step 1, And drill a plurality of second blastholes on each of the second blasting faces from the back to the front, and the plurality of the first blastholes are arranged in a fan shape and arranged counterclockwise from the back to the front. The second blast hole is fan-shaped and arranged counterclockwise from back to front; the first blast hole and the second blast hole are blast holes that gradually slope upward from back to front; thus, the The first blasthole 7 and the second blasthole 8 are blastholes drilled into the coal seam 9 to be blasted from the air inlet lane 3 from the back to the front;

Step 203, charge and hole sealing: all first blastholes and all second blastholes in step 202 are loaded with explosives on the inner side upper part, and the segments filled with explosives in the first blastholes and the second blastholes are The charging section; after the charging is completed, each first blasthole and each second blasthole are respectively sealed;

The charging sections of the first blast hole and the second blast hole are all located in the coal seam to be blasted;

Step 204, the first blasting: along the advancing direction of the working face, detonate a plurality of first blast holes on the first blasting surface from back to front, and perform the first blasting on the coal seam to be blasted in the current mining section;

Step 205, the second blasting: along the advancing direction of the working face, detonate a plurality of second blasting holes on the second blasting surface from back to front, and perform a second blasting on the coal seam to be blasted in the current mining segment;

Step 3. Coal seam mining: According to the top-coal caving mining method and from front to back along the coal seam, the current mining segment is mined until the mining process of the current mining segment is completed;

Step 4, mining of the next mining segment: mining the next mining segment according to the method described in step 1 to step 3;

Step 5. Step 4 is repeated several times until the entire mining process of the steeply inclined extra-thick coal seam is completed.

The feature of the above-mentioned steeply inclined extra-thick coal seam coal mining technology based on the weakening of top coal advance pre-explosion is that the diameters of the first blast hole and the second blast hole mentioned in step 202 are both Φ100mm-Φ120mm.

The above-mentioned coal mining technology for steeply inclined and extra-thick coal seams based on the weakening of the advanced pre-explosion of the top coal is characterized in that: when drilling blastholes in step 202, a ZDY-800 drilling rig is used for drilling; in step 203, charge and seal When drilling holes, use BCJ-5 type charge machine for forward charge, and use BQF-100 hole sealing device for hole sealing.

The above-mentioned steeply inclined extra-thick coal seam coal mining technology based on the weakening of the top-coal advance pre-explosion is characterized in that: before determining the position of the coal seam to be blasted in step 201, first determine the advance pre-explosion area of the current mining segment;

When determining the advanced pre-explosion area of the current mining segment, the front and rear end positions of the advanced pre-explosion area are determined according to the mining influence range of the current mining face;

The advanced pre-explosion area is located in front of the current mining face and its length along the advancing direction of the working face is L0=Ll ₀ , and the distances between the front and rear ends of the advanced pre-explosion area and the current mining face are L and l ₀ respectively; Among them, _l0 is the length of the mining influence range of the current mining face along the advancing direction of the working face;

In step 202, multiple blasting surfaces are all located in the advanced pre-detonation area.

The above-mentioned coal mining technology for steeply inclined and extra-thick coal seams based on the weakening of top-coal pre-explosion is characterized in that: when the current mining section is mined from front to back in step 3, the inner sides of the air inlet lane and the air return lane are both A roadway coal pillar is left, and the advanced pre-explosion area is located between two said roadway coal pillars;

When determining the advanced pre-explosion area of the current mining section, it is also necessary to carry out the boundary lines on both sides of the advanced pre-explosion area according to the width of the coal pillars left in the inner side of the pre-designed air inlet and return air lanes. Determine; the boundary lines on both sides of the advanced pre-explosion area are boundary line L1 and boundary line L2 respectively, wherein boundary line L1 is the boundary line near the side of the air inlet lane, and boundary line L2 is the boundary near the side of the return air lane Wire.

The above-mentioned coal mining technology for steeply inclined and extra-thick coal seams based on the weakening of top-coal pre-explosion is characterized in that: when determining the mining influence range of the current mining face, first monitor the support pressure of the coal body in front of the current mining face , and determine the influence range of mining according to the monitoring results; the advanced pre-explosion area is a stress balance area where the bearing pressure changes smoothly and the bearing pressure change range is less than 0.5MPa, and the mining influence range is the bearing pressure changes sharply and the support The area where the range of pressure change is not less than 0.5MPa;

When monitoring the supporting pressure of the coal body in front of the current mining face, it is monitored by a plurality of roof pressure monitors arranged in the coal body in front of the current mining face.

The feature of the above-mentioned steeply inclined extra-thick coal seam coal mining technology based on the weakening of top coal advance pre-explosion is: said l ₀ =8m~12m.

The above-mentioned steeply inclined extra-thick coal seam coal mining technology based on the weakening of the top-coal pre-explosion is characterized in that: in step 202, the number of first blast holes drilled on the first blasting surface and the number of each first blast hole The layout positions and structures are the same, the number of the second blastholes drilled on the second blasting surface and the layout positions and structures of each second blastholes are the same, and the first blastholes drilled on the first blasting surface A blasthole is arranged alternately with the second blasthole drilled on the second blasting surface;

The number of first blastholes drilled on each of the first blasting surfaces is four, and the four first blastholes are respectively 1# blasthole, 3# blasthole, and counterclockwise from back to front. 5# blasthole and 7# blasthole, the included angles between the 1# blasthole, 3# blasthole, 5# blasthole and 7# blasthole and the horizontal plane are respectively A1, A3, A5 and A7;

The number of second blastholes drilled on each of the second blasting surfaces is four, and the four second blastholes are respectively 2# blastholes, 4# blastholes, and counterclockwise from back to front. 6# blasthole and 8# blasthole, the included angles between the 2# blasthole, 4# blasthole, 6# blasthole and 8# blasthole and the horizontal plane are respectively A2, A4, A6 and A8; wherein, A1>A2>A3>A4>A5>A6>A7>A8.

The above-mentioned steeply inclined extra-thick coal seam coal mining technology based on the weakening of top coal advance pre-explosion is characterized in that: the 1# blast hole, the 2# blast hole, the 3# blast hole, the 4# blast hole, the 5# blast hole and the The tops of the 6# blastholes are all flush with the top of the coal seam to be blasted. The 1# blastholes, 2# blastholes, 3# blastholes, 4# blastholes, 5# blastholes, 6# blastholes and 7# blastholes The charge section of # blast hole is located between the boundary lines on both sides of the advanced pre-explosion area, the top of the charge section of 1# blast hole is located at the front side of the bottom end of the charge section of 2# blast hole, and the charge section of 2# blast hole The top of the charge section of the 3# blast hole is located at the front side of the bottom end of the charge section of the 3# blast hole, the top of the charge section of the 3# blast hole is located at the front side of the bottom end of the charge section of the 4# blast hole, and the charge section of the 4# blast hole The top is located at the bottom front of the charge section of the 5# blast hole, the top of the charge section of the 5# blast hole is located at the front side of the bottom end of the charge section of the 6# blast hole, and the top of the charge section of the 6# blast hole is located at the 7# The front side of the bottom of the charge section of the blasthole; the bottom of the charge section of the 1# blasthole is flush with the boundary line L1, the top of the charge section of the 8# blasthole is flush with the boundary line L2, and the top of the charge section of the 7# blasthole is flush with the boundary line L2. The top of the charge section is located below the top of the coal seam to be blasted and is located in the roadway coal pillar left inside the return airway.

The above-mentioned steeply inclined extra-thick coal seam coal mining technology based on the weakening of the top-coal pre-explosion is characterized in that: in step 202, the number of first blast holes drilled on the first blasting surface and the number of each first blast hole The layout positions and structures are the same, the number of the second blastholes drilled on the second blasting surface and the layout positions and structures of each second blastholes are the same, and the first blastholes drilled on the first blasting surface A blasthole is arranged alternately with the second blasthole drilled on the second blasting surface.

Compared with the prior art, the present invention has the following advantages:

1. The process steps are simple, the design is reasonable and the realization is convenient, and the input cost is low.

2. High mining efficiency can effectively shorten the construction period.

3. The structural design of the advanced pre-explosion net adopted is reasonable, the drilling is convenient and the use effect is good. The advanced pre-explosion area is divided into multiple blasting surfaces, and the multiple blasting surfaces are arranged from front to back and all of them are advanced with the working face The direction is a vertically arranged plane, and multiple blasting surfaces are divided into two types: the first blasting surface and the second blasting surface. The first blasting surface and the second blasting surface are arranged in a staggered manner; A plurality of first blastholes, and a plurality of second blastholes are drilled on each second blasting surface. Both the first and second holes are drilled inwardly from the completed air inlet lane by using a drilling rig. A plurality of first blastholes are arranged in a fan shape and arranged from back to front in a counterclockwise direction, a plurality of second blastholes are arranged in a fan shape and arranged in a counterclockwise direction from back to front, and the first blastholes and The second blastholes are all blastholes that gradually slope upward from the back to the front. In this way, not only the drilling construction is convenient, but also the blasting is carried out in two stages, which can effectively reduce the number of blasting holes while ensuring the top coal pre-splitting effect, save time, manpower and material costs, and greatly speed up the mining efficiency. At the same time, due to the reduction in the number of blastholes, the distance between two adjacent primary blastholes and the distance between two adjacent secondary blastholes increases accordingly, which can effectively reduce the damage of the drilled blastholes to the air inlet lane.

4. The advanced pre-explosion weakening method of the top coal is simple in steps, reasonable in design, easy to implement, and good in use. The design of each process is reasonable, and all processes of the advanced pre-explosion weakening of the top coal are carried out in the air inlet lane. Not only the construction It is convenient, and the construction equipment is easy to move, saving labor and time, and the construction progress is fast. Moreover, less construction equipment is used in the weakening process of the top-coal pre-explosion and the operation is simple, which can fully realize the continuous mechanized operation.

5. Before the pre-explosion of the top coal is weakened, first determine the position of the pre-explosion area, specifically in the direction of height (that is, the direction perpendicular to the direction of advancement of the working face), the direction of advancement of the working face, and the direction of the length of the working face The boundary line of the pre-explosion area is determined respectively, and the boundary line in the height direction of the pre-explosion area is consistent with the height of the top and bottom of the coal seam to be blasted. Moreover, when determining the position of the advanced pre-detonation area, the method adopted is reasonable and convenient to implement, and has good application effect.

6. The mining process is safe and reliable, and there are few potential safety hazards, in line with the national safety production regulations - the provisions of Article 68 of the "Coal Mine Safety Regulations" announced and implemented by the State Administration of Work Safety and the State Coal Mine Safety Supervision Bureau in 2006.

7. The overall mining process is simple and the design is reasonable. The steeply inclined ultra-thick coal seam is mined in multiple mining sections from the back to the front along the advancing direction of the working face. Each mining section includes roadway construction, top-coal advance pre-explosion weakening and There are three coal seam mining processes, so the overall optimization of the existing steeply inclined and extra thick coal seam coal mining process is carried out, and the existing steeply inclined and extra thick coal seam mining process is substantially adjusted, which improves the continuity of production at the working face and speeds up the production process. The advancement speed of the working face has been improved, and the comprehensive mechanized operation and uninterrupted implementation of each process has been realized, which can effectively solve the problems of low recovery rate of the working face, many safety hazards, large loss of coal resources, complex production processes, and problems existing in the existing coal mining technology. Issues such as the continuity of production and the speed of advancement cannot be guaranteed. At the same time, the recovery rate of the working face is high, and it can effectively reduce the dust concentration of the working flour, protect the health of the workers, increase the production output, and greatly reduce the production cost.

8. The use effect is good, the practical value is high, and the prospect of popularization and application is broad, which is mainly reflected in the following aspects: First, the blasting cost is significantly reduced: due to the small number of blast holes and the reasonable design of each blast hole position and charge, the blasting material Consumption has been greatly reduced, and the cost of coal per ton has dropped from the highest 4.469 yuan to 1.731 yuan. The consumption of blasting materials is reduced by 13.4% compared with the blasting in front of the frame; second, the construction efficiency is greatly improved, and a comprehensive mechanized operation is realized; third, the production time and progress are improved: due to the optimization of the overall mining process, the production process is different from each other Interference, production time balance and continuity have been improved, the daily advance rate has increased from 2.4 meters to 3.0 meters, and the advance rate has increased by 25%. The production time has been significantly improved by more than 20%; fourthly, the labor intensity of workers has also been significantly reduced. Therefore, the present invention has the advantages of less material consumption, reasonable process design, significantly improved advancement and production continuity, significantly improved main economic and technical indicators such as comprehensive cost and recovery rate, significant economic and social benefits, and has great popularization and application value.

In summary, the present invention has simple process steps, reasonable design, high mining efficiency, high working face recovery rate, and good use effect, and can solve the existing coal mining technology with complicated process, low working face recovery rate and many safety hazards. , Low mining efficiency and other issues.

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

Description of drawings

Figure 1-1 is a schematic diagram of blasthole layout positions used in the existing top-coal caving mining process.

Figure 1-2 is a cross-sectional view along line A-A of Figure 1-1.

Fig. 2 is a process flow diagram of the present invention.

Fig. 3 is a schematic diagram of the arrangement positions of the drilled first blast hole and the second blast hole in the direction vertical to the advancing direction of the working face according to the present invention.

Fig. 4 is a schematic diagram of the plane position of the charging section for drilling the first blast hole and the second blast hole in the advancing direction of the working face according to the present invention.

Fig. 5 is a diagram showing the variation of the support pressure of the coal body in front of the current mining face monitored by the roof pressure monitor in the present invention.

Explanation of reference signs:

1—working face support; 1-1—coal mining face; 1-2—coal shearer;

2-1—front blast hole; 2-2—rear row blast hole; 3—air intake lane;

4—air return lane; 5—roof protection coal seam; 6—coal pillar of road protection;

7—the first blast hole; 8—the second blast hole; 9—the coal seam needs to be blasted;

10—Protection coal seam of working face; 11—Current mining face; 12-1—Charging hole section;

12-2—The sealing hole section.

Detailed ways

A kind of steeply inclined extra-thick coal seam coal mining technology based on the weakening of top-coal advance pre-explosion as shown in Figure 2, the steeply inclined extra-thick coal seam exploited is a coal seam with a coal seam dip angle of more than 45° and a coal seam thickness of more than 8m; When mining a steeply inclined and extra-thick coal seam, the steeply inclined and extra-thick coal seam is mined in multiple mining sections from the back to the front along the coal seam trend. The length above is L, wherein L=30m～50m; When mining a mining segment of the steeply inclined extra-thick coal seam, the process is as follows:

Step 1. Roadway construction: construct a ventilation roadway on the left and right sides of the lower part of the current mining section, and the two ventilation roadways are the air inlet lane 3 and the air return lane 4 respectively.

Step 2. Top-coal advanced pre-explosion weakening: The current mining segment is subjected to top-coal advanced pre-explosion weakening, the process is as follows:

Step 201, determine the coal seam to be blasted: according to the thickness of the roof protection coal seam 5 left in the mining process of the current mining segment and the mining height of the working face in advance, determine the top and bottom heights of the coal seam 9 to be blasted in the current mining segment ;

The top coal above the mining face of the current mining section is divided into three coal seams from bottom to top: the coal seam 5 for roof protection, the coal seam 9 to be blasted, and the coal seam 10 to protect the working face. Among the protected coal seams 10 ; wherein, the mining face of the current mining segment is the current mining face 11 , and the working face support 1 is supported on the current mining face 11 . The top coal above the mining face of the current mining segment refers to the coal seam between the current mining face 11 and the roof in the current mining segment and is the coal seam above the current mining face 11 in the current mining segment.

In this embodiment, after the height of the top and bottom of the coal seam 9 to be blasted is determined in step 201, the top boundary line L3 and the bottom boundary line L4 of the coal seam 9 to be blasted can be obtained. Among them, the top boundary line L3 is also called the roof protection coal line, the bottom boundary line L4 is also called the working face protection coal line, and both the top boundary line L3 and the bottom boundary line L4 are horizontal lines.

In this embodiment, the thickness of the working face protection coal seam 10 is 3m-5m, and the thickness of the roof protection coal seam 5 is 3m-5m.

Therefore, the distance between the bottom of the coal seam 9 to be blasted and the top of the current mining face 11 is 3m-4m.

Step 202, blasting hole drilling: first select a plurality of blasting faces on the coal seam 9 to be blasted in front of the current mining face 11 along the advancing direction of the working face. The advancing direction of the surface is a plane arranged vertically, and the distance between two adjacent blasting surfaces is 3m to 5m; the plurality of blasting surfaces include a plurality of first blasting surfaces and a plurality of second blasting surfaces, and the first The first blasting surface and the second blasting surface are arranged in a staggered manner; after that, use a drilling rig to drill a plurality of first blasting tunnels from the air inlet lane 3 constructed in step 1 from back to front on each of the first blasting surfaces. blast holes 7, and drill a plurality of second blast holes 8 on each of the second blasting surfaces from back to front. The layout is carried out in front, and a plurality of the second blastholes 8 are arranged in a fan shape and they are arranged in a counterclockwise direction from the back to the front; the first blastholes 7 and the second blastholes 8 are gradually upward from the back to the front. For inclined blast holes, see Figure 3 and Figure 4 for details. In Figure 3 and Figure 4, the black bold section is the charge section.

In this embodiment, the distance between two adjacent blasting surfaces is 4m. Correspondingly, the distance between two adjacent first blasting surfaces and between two adjacent second blasting surfaces Both are 8m.

During actual construction, the distance between two adjacent blasting surfaces can be adjusted accordingly according to specific needs.

Step 203, charge and hole sealing: all the inner upper parts of all the first blastholes 7 and all the second blastholes 8 in step 202 are filled with explosives, the first blastholes 7 and the second blastholes 8 are filled with explosives The segments are charge segments; after the charge is completed, each first blasthole 7 and each second blasthole 8 are sealed;

Both the charge sections of the first blast hole 7 and the second blast hole 8 are located in the coal seam 9 to be blasted. That is to say, the top heights of the charge sections of all the first blastholes 7 and all the second blastholes 8 are not higher than the top height of the coal seam 9 to be blasted and the bottom heights are higher than the bottom height of the coal seam 9 to be blasted.

In this embodiment, after the charging of the first blast hole 7 or the second blast hole 8 is completed, processes such as placing a detonator and a wire are carried out, and then the holes are sealed. And, each gun hole is equipped with 4 rounds of detonators.

When actually sealing the holes, the sealing material is yellow mud, and the hole sections in the first blast hole 7 and the second blast hole 8 are completely sealed except for the charging section. That is to say, the first blasthole 7 and the second blasthole 8 are both divided into a charging hole section 12-1 and a sealing hole section 12-2.

Step 204, the first blasting: along the advancing direction of the working face, detonate a plurality of first blast holes 7 on the first blasting surface from back to front, and perform the first blasting on the coal seam 9 to be blasted in the current mining section .

Step 205, the second blasting: along the advancing direction of the working face, detonate a plurality of second blast holes 8 on the second blasting surface from the back to the front, and perform the second blasting on the coal seam 9 to be blasted in the current mining section .

Step 3. Coal seam mining: According to the top-coal caving mining method and from front to back along the coal seam, the current mining segment is mined until the mining process of the current mining segment is completed. When actually mining the coal seam, mining starts from the current mining face 11 .

Step 4. Mining of the next mining segment: Mining the next mining segment according to the method described in step 1 to step 3.

Step 5. Step 4 is repeated several times until the entire mining process of the steeply inclined extra-thick coal seam is completed.

In this embodiment, when the current mining section is mined, the mining face is used. As we all know, for the sake of safety, mine mining is generally carried out from the front to the back, and the roadway is opened first to enter the distance of the planned mining area. The working face during formal mining is called the back mining face. Therefore, during mining, the direction of the coal seam is opposite to the advancing direction of the working face of the mining face.

Before the actual mining, according to the layout positions of the multiple mining segments, the multiple mining segments are mined from back to front along the coal seam. When mining each mining segment, start from the mining face of the mining segment and mine from front to back along the coal seam; in terms of the advancing direction of the working face, start from the mining face from the back to the front. Sections are mined.

Therefore, the plurality of blasting surfaces selected in step 202 are located on the coal seam 9 to be blasted ahead of the current mining face 11 along the advancing direction of the working face; The rear side of the working surface 11.

In this embodiment, the diameters of the first blast hole 7 and the second blast hole 8 in step 202 are both Φ100mm˜Φ120mm.

The explosives loaded in the first blast hole 7 and the second blast hole 8 in step 203 are all latex matrix.

During actual construction, the diameters of the first blast hole 7 and the second blast hole 8 can be adjusted accordingly according to specific needs. Moreover, the explosives loaded in the first blast hole 7 and the second blast hole 8 may also be other types of mining explosives.

In this embodiment, when the blast hole is drilled in step 202, the ZDY-800 type drilling machine is used for drilling; when the charge and hole sealing are carried out in the step 203, the BCJ-5 type charge machine is used for forward charge, Use BQF-100 hole sealing device for sealing.

When using the ZDY-800 drilling rig for drilling, the average drilling time for each blast hole is about 1.13 minutes. Compared with the existing general-purpose drilling rig, the drilling time is reduced by 50%, and the drilling speed is greatly improved; at the same time, The rod unloading time (that is, the dismantling time of the drill pipe) in the drilling process is also reduced, compared with the existing general-purpose drilling rig, the rod unloading time is reduced by about 14%. In addition, the holes drilled by the existing general-purpose drilling rig have large deviations, and the drill pipe is prone to skew when encountering gangue; while the drill pipe of the ZDY-800 drilling rig has no deformation, accurate positioning, straight holes, and high precision, which improves the drilling quality. Hole construction effect, especially suitable for advanced drilling construction in coal mines.

Nowadays, when charging the blast hole, it is mainly filled manually with the gun stick. The charging time after using the BCJ-5 charging machine is greatly reduced, and the charging time is only 8.86% of the manual charging time. %. It is found by comparison that, compared with manual charging, using a charging machine is fast, safe and fast, and the blasting effect of the latex matrix is also better than that of the emulsion explosive.

During actual construction, other types of drilling rigs, charge machines and hole sealers can also be used.

In this embodiment, before determining the position of the coal seam to be blasted in step 201, the advanced pre-explosion area of the current mining segment is determined first.

When determining the advanced pre-detonation area of the current mining section, the front and rear end positions of the advanced pre-explosion area are determined according to the mining influence range of the current mining face 11 .

The advanced pre-explosion area is located in front of the current mining face 11 and its length along the advancing direction of the working face is L0=Ll ₀ , the distances between the front and rear ends of the advanced pre-explosion area and the current mining face 11 are L and l respectively ₀ ; Among them, l ₀ is the length of the mining influence range of the current mining face 11 along the advancing direction of the working face. Here, the advanced pre-detonation area is located in front of the current mining face 11, which means that the advanced pre-explosion area is located in front of the current mining face 11 along the advancing direction of the working face.

In step 202, multiple blasting surfaces are all located in the advanced pre-detonation area.

In this embodiment, when determining the scope of influence of mining on the current mining face 11, first monitor the support pressure of the coal body in front of the current mining face 11, and determine the scope of influence on mining according to the monitoring results; The advanced pre-explosion area is a stress balance area where the bearing pressure changes steadily and the range of bearing pressure change is less than 0.5MPa.

When the support pressure of the coal body in front of the current mining face 11 is monitored, it is monitored by a plurality of roof pressure monitors arranged in the coal body in front of the current mining face 11 . Here, the coal body in front of the current mining face 11 refers to the coal body whose advancing direction of the working face is in front of the current mining face 11 .

And, for the convenience of layout, the roof pressure monitor is arranged on the coal body above the ventilation roadway.

According to Article 68 of the "Coal Mine Safety Regulations", the blasting location should avoid the area affected by the mining activity. To this end, mine pressure monitoring is carried out at the current mining face 11 to grasp the change law of the advanced bearing pressure, analyze and determine the mining influence range of the working face, and then determine the specific location of the advanced pre-explosion area.

As shown in FIG. 5 , the monitoring results of the roof pressure monitor reflect the dynamic evolution law of the coal support pressure on the ventilation roadway of the current mining face. It can be clearly seen from Fig. 5 that starting from the coal wall of the current mining face, within the range of 0-10.0m, the coal support pressure changes drastically, and the peak value reaches about 2.0MPa; within the range of 10m-50m, the coal support pressure is between Within the range of 0.2MPa ~ 0.5MPa, it is basically stable, so it is determined that the length of the mining influence range of the current mining face 11 is 10m. Position 10m behind the wall.

In this embodiment, when the current mining section is mined from front to back in step 3, a roadway coal pillar 6 is left inside the air inlet lane 3 and the air return lane 4, and the advanced pre-explosion area Located between the two coal pillars 6 of the roadway protection;

When determining the advanced pre-explosion area of the current mining section, it is also necessary to determine the width of the protection roadway coal pillar 6 on the inside of the pre-designed air inlet roadway 3 and return airway 4, on both sides of the advanced pre-explosion area The boundary line is determined; the boundary lines on both sides of the pre-explosion area are respectively the boundary line L1 and the boundary line L2, wherein the boundary line L1 is the boundary line close to the side of the air inlet lane 3, and the boundary line L2 is the boundary line close to the return air lane 4 Borderlines on one side.

In this embodiment, the width of the roadway protection coal pillar 6 is 3m-6m. Wherein, the boundary line L1 is the inner boundary line of the roadway protection coal pillar 6 left inside the air inlet roadway 3, and the boundary line L2 is the inner boundary line of the roadway protection coal pillar 6 left inside the air return roadway 4.

During actual construction, _l0 can be set as 8m~12m according to the actual construction. During the construction process, the value of _l0 can be adjusted accordingly according to specific needs.

Among them, the units of L0 and _l0 are m. The mining influence range is the range in front of the current mining face 11 with a length of ₁₀ .

In this embodiment, in step 202, the number of the first blastholes 7 drilled on the multiple first blasting surfaces and the layout positions and structures of the first blastholes 7 are the same, and the multiple second blasting surfaces The number of the second blastholes 8 drilled on the top and the layout position and structure of each second blasthole 8 are the same, and the first blastholes 7 drilled on the first blasting surface are the same as those drilled on the second blasting surface. The second blastholes 8 taken are arranged in a staggered manner.

The number of first blastholes 7 drilled on each of the first blasting surfaces is four, and the four first blastholes 7 are respectively 1# blasthole and 3# blasthole from back to front in the counterclockwise direction. hole, 5# blast hole and 7# blast hole, the included angles between the 1# blast hole, 3# blast hole, 5# blast hole and 7# blast hole and the horizontal plane are A1, A3, A5 and A7 respectively.

The number of second blastholes 8 drilled on each of the second blasting surfaces is four, and the four second blastholes 8 are respectively 2# blastholes and 4# blastholes from back to front in the counterclockwise direction. hole, 6# blasthole and 8# blasthole, the included angles between the 2# blasthole, 4# blasthole, 6# blasthole and 8# blasthole and the horizontal plane are A2, A4, A6 and A8 respectively; Among them, A1>A2>A3>A4>A5>A6>A7>A8.

During actual construction, the number of first blast holes 7 and the layout positions of each first blast hole 7 can be drilled on each of the first blasting faces and the number of first blast holes 7 can be drilled on each of the second blasting faces according to specific needs. The quantity of the second blastholes 8 and the layout positions of the second blastholes 8 are adjusted accordingly.

In the present embodiment, the center line of the 1# blasthole, 2# blasthole, 3# blasthole, 4# blasthole, 5# blasthole, 6# blasthole, 7# blasthole and 8# blasthole They all intersect at the same point O, which is located in the middle of the air inlet lane 3.

In this embodiment, the blasting surface in front of the current mining face 11 is divided into two types: the first blasting surface and the second blasting surface, and the first blastholes 7 and the second blastholes 8 are arranged in a staggered manner, which is divided into two Blasting successively can effectively reduce the number of blasting holes, save time, manpower and material costs while ensuring the pre-splitting effect of the top coal and effectively blasting the coal seam 9 to be blasted, and can greatly speed up the mining efficiency; meanwhile, due to the number of blasting holes The distance between two adjacent primary blastholes 7 and the distance between two adjacent secondary blastholes 8 increases correspondingly, which can effectively reduce the damage to the air inlet lane 3 caused by the drilled blastholes.

In this embodiment, the tops of the 1# blast hole, 2# blast hole, 3# blast hole, 4# blast hole, 5# blast hole and 6# blast hole are all flush with the top of the coal seam 9 to be blasted , the charge sections of the 1# blasthole, 2# blasthole, 3# blasthole, 4# blasthole, 5# blasthole, 6# blasthole and 7# blasthole are all located at the front of the pre-explosion zone Between the boundary lines on both sides, the top of the charge section of the 1# blasthole is located in front of the bottom of the charge section of the 2# blasthole, and the top of the charge section of the 2# blasthole is located at the bottom of the charge section of the 3# blasthole On the front side, the top of the charge section of the 3# blasthole is located at the front side of the bottom end of the charge section of the 4# blasthole, the top of the charge section of the 4# blasthole is located at the front side of the bottom end of the charge section of the 5# blasthole, 5 The top of the charge section of the # blast hole is located at the front side of the bottom end of the charge section of the 6# blast hole, and the top of the charge section of the 6# blast hole is located at the front side of the bottom end of the charge section of the 7# blast hole; The bottom of the charge section is flush with the boundary line L1, the top of the charge section of the 8# blasthole is flush with the boundary line L2, and the top of the charge section of the 7# blasthole is located below the top of the coal seam 9 to be blasted and located at the back In the roadway coal pillar 6 that wind lane 4 inner side stays.

To sum up, all the processes of top-coal advanced pre-explosion weakening in step 2 are implemented in the air inlet lane 3, which not only facilitates construction, but also facilitates the displacement of construction equipment, saves labor and time, and the construction progress is fast. Moreover, less construction equipment is used in the weakening process of the top-coal pre-explosion and the operation is simple, which can fully realize the continuous mechanized operation.

In this embodiment, the number of the first blasting surface is the same as that of the second blasting surface, two adjacent blasting surfaces are divided into one group, and each group of the blasting surfaces includes one of the first blasting surfaces. A blasting surface and a second blasting surface adjacent to the first blasting surface, all the first blasting holes 7 and all the second blasting holes 8 in each group of blasting surfaces form a blasting hole group, and the blasting hole group runs through The entire coal seam 9 to be blasted realizes the advanced pre-blasting of a single blast hole group.

In this embodiment, the layout parameters of the four first blastholes 7 and the four second blastholes 8 are shown in Table 1:

Table 1 Bunker Hole Layout Parameters

The above are only preferred embodiments of the present invention, and do not limit the present invention in any way. All simple modifications, changes and equivalent structural changes made to the above embodiments according to the technical essence of the present invention still belong to the technical aspects of the present invention. within the scope of protection of the scheme.

Claims (10)

1. The utility model provides a coal mining technology of steeply inclined super thick coal seam based on top coal advanced pre-explosion weakening, the coal seam that steeply inclined super thick coal seam that minees is more than 45 and more than 8m of coal seam inclination, its characterized in that: mining the steeply inclined extra-thick coal seam by dividing the steeply inclined extra-thick coal seam into a plurality of mining sections from back to front along the coal seam trend, wherein the mining methods of the plurality of mining sections are the same, and the lengths of the mining sections along the coal seam trend are all L, wherein L is 30-50 m; when a mining section of the steep extra-thick coal seam is mined, the process is as follows:

step one, roadway construction: constructing a ventilation roadway on the left side and the right side of the lower part of the current mining section respectively, wherein the two ventilation roadways are an air inlet roadway (3) and an air return roadway (4) respectively;

step two, top coal advanced pre-explosion weakening: and (3) carrying out top coal advanced pre-explosion weakening on the current mining section, wherein the process is as follows:

step 201, determining a coal seam to be blasted: respectively determining the top and bottom heights of the coal seam (9) to be blasted of the current mining section according to the thickness of the reserved top-protecting coal seam (5) and the mining height of the working face in the mining process of the current mining section which are designed in advance;

top coal above a stope face of a current mining section is divided into three coal seams, namely a top protecting coal seam (5), a coal seam (9) to be blasted and a face protecting coal seam (10), from bottom to top, wherein the coal seam (9) to be blasted is positioned between the top protecting coal seam (5) and the face protecting coal seam (10); wherein the stope face of the current mining section is a current stope face (11);

step 202, drilling a blast hole: selecting a plurality of blasting surfaces on a coal seam (9) to be blasted in front of a current stope working face (11) along the working face propelling direction, wherein the plurality of blasting surfaces are arranged from front to back and are planes which are arranged vertically to the working face propelling direction, and the distance between every two adjacent blasting surfaces is 3-5 m; the plurality of blasting surfaces comprise a plurality of first blasting surfaces and a plurality of second blasting surfaces, and the first blasting surfaces and the second blasting surfaces are distributed in a staggered manner; drilling a plurality of first blast holes (7) on each first blasting surface from back to front and a plurality of second blast holes (8) on each second blasting surface from back to front by using a drilling machine from the air inlet lane (3) constructed in the first step, wherein the first blast holes (7) are distributed in a fan shape and are distributed from back to front along the anticlockwise direction, and the second blast holes (8) are distributed in a fan shape and are distributed from back to front along the anticlockwise direction; the first blast hole (7) and the second blast hole (8) are both blast holes which are gradually inclined upwards from back to front;

step 203, charging and hole sealing: filling explosive into the upper parts of the inner sides of all the first blast holes (7) and all the second blast holes (8) in the step 202, wherein the sections filled with the explosive in the first blast holes (7) and the second blast holes (8) are all explosive sections; after charging is finished, sealing the first blast holes (7) and the second blast holes (8) respectively;

the charging sections of the first blast hole (7) and the second blast hole (8) are positioned in a coal seam (9) to be blasted;

step 204, first blasting: detonating a plurality of first blast holes (7) on the first blasting surface from back to front along the advancing direction of the working surface, and blasting the coal seam (9) to be blasted of the current mining section for the first time;

step 205, second blasting: detonating a plurality of second blast holes (8) on the second blasting surface from back to front along the advancing direction of the working surface, and blasting the coal seam (9) to be blasted of the current mining section for the second time;

step three, coal seam mining: carrying out stoping on the current mining section from front to back along the coal seam trend according to a caving coal mining method until the mining process of the current mining section is completed;

step four, mining the next mining section: mining the next mining section according to the method described in steps one through three;

and fifthly, repeating the step four for multiple times until the whole mining process of the steeply inclined super-thick coal seam is completed.

2. The top coal advanced pre-explosion weakening based high-dipping extra-thick coal seam coal mining process according to claim 1, wherein the process comprises the following steps: in the step 202, the aperture diameters of the first blast hole (7) and the second blast hole (8) are phi 100 mm-phi 120 mm.

3. The top coal advanced pre-explosion weakening based high-dipping extra-thick coal seam coal mining process according to claim 1 or 2, wherein the process comprises the following steps: when the blast hole is drilled in the step 202, drilling by adopting a ZDY-800 type drilling machine; and in the step 203, when charging and hole sealing are carried out, a BCJ-5 type charging machine is adopted for carrying out forward charging, and a BQF-100 hole sealing device is adopted for carrying out hole sealing.

4. The top coal advanced pre-explosion weakening based high-dipping extra-thick coal seam coal mining process according to claim 1 or 2, wherein the process comprises the following steps: before the position of the coal seam to be blasted is determined in the step 201, determining an advanced pre-blasting area of a current mining section;

when an advanced pre-explosion area of a current mining section is determined, determining the front end position and the rear end position of the advanced pre-explosion area according to the mining influence range of a current stope face (11);

the advanced pre-explosion area is positioned in front of the current stope working face (11) and has a length L0 (L-L) in the advancing direction of the working face₀The distances between the front end and the rear end of the advanced pre-explosion area and the current stope face (11) are respectively L and L₀(ii) a Wherein l₀The length of the mining influence range of the current stope working face (11) along the advancing direction of the working face;

in step 202, a plurality of the blast surfaces are all located in the advanced pre-detonation zone.

5. The mining process of the steeply inclined super-thick coal seam based on top coal advanced pre-explosion weakening as claimed in claim 4, wherein: when the current mining section is mined from front to back in the third step, a roadway protection coal pillar (6) is reserved on the inner sides of the air inlet roadway (3) and the air return roadway (4), and the advanced pre-explosion area is located between the two roadway protection coal pillars (6);

when the advanced pre-explosion area of the current mining section is determined, determining the boundary lines at two sides of the advanced pre-explosion area according to the width of a protective roadway coal pillar (6) reserved on the inner sides of a pre-designed air inlet roadway (3) and a pre-designed air return roadway (4); boundary lines on two sides of the advanced pre-explosion area are a boundary line L1 and a boundary line L2 respectively, wherein the boundary line L1 is a boundary line close to one side of the air inlet lane (3), and the boundary line L2 is a boundary line close to one side of the air return lane (4).

6. The mining process of the steeply inclined super-thick coal seam based on top coal advanced pre-explosion weakening as claimed in claim 4, wherein: when the mining influence range of the current stope face (11) is determined, monitoring the supporting pressure of a coal body in front of the current stope face (11), and determining the mining influence range according to a monitoring result; the advanced pre-explosion area is a stress balance area with stable change of supporting pressure and the change amplitude of the supporting pressure less than 0.5MPa, and the mining influence range is an area with violent change of the supporting pressure and the change amplitude of the supporting pressure not less than 0.5 MPa;

when the supporting pressure of the coal body in front of the current stope face (11) is monitored, a plurality of roof pressure monitors arranged in the coal body in front of the current stope face (11) are used for monitoring.

7. The mining process of the steeply inclined super-thick coal seam based on top coal advanced pre-explosion weakening as claimed in claim 4, wherein: l is₀＝8m～12m。

8. The top coal advanced pre-explosion weakening based high-dipping extra-thick coal seam coal mining process according to claim 5, wherein the process comprises the following steps: in step 202, the number of first blast holes (7) drilled in the plurality of first blasting surfaces and the arrangement positions and structures of the first blast holes (7) are the same, the number of second blast holes (8) drilled in the plurality of second blasting surfaces and the arrangement positions and structures of the second blast holes (8) are the same, and the first blast holes (7) drilled in the first blasting surfaces and the second blast holes (8) drilled in the second blasting surfaces are arranged in a staggered manner;

the number of the first blast holes (7) drilled in each first blasting surface is four, the four first blast holes (7) are respectively a No. 1 blast hole, a No. 3 blast hole, a No. 5 blast hole and a No. 7 blast hole from back to front along the counterclockwise direction, and included angles between the No. 1 blast hole, the No. 3 blast hole, the No. 5 blast hole and the No. 7 blast hole and the horizontal plane are respectively A1, A3, A5 and A7;

the number of second blast holes (8) drilled in each second blasting surface is four, the four second blast holes (8) are respectively a No. 2 blast hole, a No. 4 blast hole, a No. 6 blast hole and a No. 8 blast hole from back to front along the counterclockwise direction, and included angles between the No. 2 blast hole, the No. 4 blast hole, the No. 6 blast hole and the No. 8 blast hole and the horizontal plane are respectively A2, A4, A6 and A8; wherein A1 & gtA 2 & gtA 3 & gtA 4 & gtA 5 & gtA 6 & gtA 7 & gtA 8.

9. The mining process of the steeply inclined super-thick coal seam based on top coal advanced pre-explosion weakening as claimed in claim 8, wherein: the top ends of the No. 1 blast hole, the No. 2 blast hole, the No. 3 blast hole, the No. 4 blast hole, the No. 5 blast hole and the No. 6 blast hole are all level with the top of the coal seam (9) to be blasted, the explosive charging sections of the No. 1 blast hole, the No. 2 blast hole, the No. 3 blast hole, the No. 4 blast hole, the No. 5 blast hole, the No. 6 blast hole and the No. 7 blast hole are all located between boundary lines on two sides of the advanced pre-explosion area, the top end of the explosive charging section of the No. 1 blast hole is located on the front side of the bottom end of the explosive charging section of the No. 2 blast hole, the top end of the explosive charging section of the No. 2 blast hole is located on the front side of the bottom end of the explosive charging section of the No. 3 blast hole, the top end of the explosive charging section of the No. 3 blast hole is located on the front side of the bottom end of the explosive charging section of the No. 4 blast hole, the top end of the explosive charging section of the No. 4 blast hole is located on the front side of the bottom end of the explosive charging section of the No. 5 blast hole; the bottom end of the charging section of the 1# blast hole is flush with the boundary line L1, the top end of the charging section of the 8# blast hole is flush with the boundary line L2, and the top end of the charging section of the 7# blast hole is positioned below the top of the coal seam (9) to be blasted and is positioned in a roadway protection coal pillar (6) reserved on the inner side of the return airway (4).

10. The top coal advanced pre-explosion weakening based high-dipping extra-thick coal seam coal mining process according to claim 1 or 2, wherein the process comprises the following steps: in step 202, the number of the first blast holes (7) drilled on the plurality of first blasting surfaces and the arrangement position and structure of each first blast hole (7) are the same, the number of the second blast holes (8) drilled on the plurality of second blasting surfaces and the arrangement position and structure of each second blast hole (8) are the same, and the first blast holes (7) drilled on the first blasting surfaces and the second blast holes (8) drilled on the second blasting surfaces are arranged in a staggered manner.