CN115434706A - Mining method for changing large coal pillar working face into small coal pillar working face - Google Patents
Mining method for changing large coal pillar working face into small coal pillar working face Download PDFInfo
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- CN115434706A CN115434706A CN202210943537.6A CN202210943537A CN115434706A CN 115434706 A CN115434706 A CN 115434706A CN 202210943537 A CN202210943537 A CN 202210943537A CN 115434706 A CN115434706 A CN 115434706A
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- 239000003245 coal Substances 0.000 title claims abstract description 157
- 238000005065 mining Methods 0.000 title claims abstract description 35
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000005520 cutting process Methods 0.000 claims abstract description 53
- 238000000605 extraction Methods 0.000 claims abstract description 25
- 239000011435 rock Substances 0.000 claims abstract description 12
- 230000005641 tunneling Effects 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 238000009412 basement excavation Methods 0.000 claims description 4
- 238000005422 blasting Methods 0.000 claims description 3
- 239000004568 cement Substances 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 claims description 3
- 230000000694 effects Effects 0.000 claims description 3
- 239000010881 fly ash Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 238000012544 monitoring process Methods 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims description 2
- 208000008918 voyeurism Diseases 0.000 claims description 2
- 230000000903 blocking effect Effects 0.000 claims 1
- 238000005187 foaming Methods 0.000 claims 1
- 239000002699 waste material Substances 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 230000000368 destabilizing effect Effects 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C41/00—Methods of underground or surface mining; Layouts therefor
- E21C41/16—Methods of underground mining; Layouts therefor
- E21C41/18—Methods of underground mining; Layouts therefor for brown or hard coal
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B29/00—Cutting or destroying pipes, packers, plugs or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows; Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F7/00—Methods or devices for drawing- off gases with or without subsequent use of the gas for any purpose
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- Life Sciences & Earth Sciences (AREA)
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- Geochemistry & Mineralogy (AREA)
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Abstract
The invention provides a mining method for changing a large coal pillar working face into a small coal pillar working face, which comprises the following steps: s1, arranging a stope face and a take-over face on a coal seam; s2, setting a stoping face hole cutting lane, a stoping face air inlet lane, a stoping face air return lane, a replacing face hole cutting lane, a replacing face air inlet lane and a replacing face air return lane, wherein a gas extraction pipeline and an underground chamber are arranged in the large coal pillar; s3, performing roof cutting and pressure relief on the roof in the air inlet roadway of the stope face to form a cutting seam; s4, stoping on a stoping surface, so that a roof rock stratum collapses along the cutting seam to form a goaf; s5, grouting and filling when the underground chamber is approached; s6, when the stoping working face pushes a certain distance of the gas extraction pipeline, filling, plugging and cutting the gas extraction pipeline; s7, excavating a small coal pillar roadway in a hole cutting mode on the replacing surface until the small coal pillar roadway is communicated, changing a large coal pillar working surface into a small coal pillar working surface, and forming a new replacing working surface; and S8, stoping the coal pillar roadway along the small coal pillar on the replacing working face. The invention is safe and reliable and has high extraction rate.
Description
Technical Field
The invention relates to the technical field of coal mining, in particular to a mining method for changing a large coal pillar working face into a small coal pillar working face, which is related to a coal seam mining method for the large coal pillar working face.
Background
With the increase of the coal mining depth and the improvement of the mining intensity, in order to prevent roadway deformation and ensure mine mining and taking over, a working face is arranged in a mode of reserving large coal pillars in part of mines, and the resource waste is serious. In the traditional roadway with small coal pillars, the excavation is generally required to be carried out after the stoping of the near working face is finished and the goaf is stable, and the waiting time is long, so that the normal excavation and replacement of the mine are influenced.
In recent years, with the improvement of roadway arrangement and supporting theory and technical level, more and more mines start to adopt small coal pillar mining technology, but because the large coal pillar working face of the mine is already arranged, and the arrangement of the small coal pillar roadway faces the influences of factors such as chambers, gas pipelines, ventilation, transportation and the like, the problems are solved, the small coal pillar mining is realized, and the major problems of result puzzlement and influence on coal mine safety and high-efficiency mining are solved.
Disclosure of Invention
The invention aims to provide a mining method for changing a large coal pillar working face into a small coal pillar working face, which aims to overcome the defects that the mining difficulty is higher when the large coal pillar working face of a mine is already arranged and changed into the small coal pillar working face in the background technology, and is safe, reliable and high in mining rate.
In order to achieve the purpose, the invention provides the following technical scheme:
a method for mining a large coal pillar working face by changing a small coal pillar working face comprises the following steps:
the method comprises the following steps that S1, two working faces, namely a stope working face and a take-over working face, are arranged on a coal seam, and the stope working face and the take-over working face are respectively arranged on two sides of a large coal pillar;
s2, a stope face cutting hole lane, a stope face air intake lane and a stope face air return lane are arranged on the stope face, and a plurality of chambers are arranged on the side of a large coal pillar close to one side of the stope face air intake lane; the taking-over working face is provided with a taking-over face hole cutting lane, a taking-over face air inlet lane and a taking-over face air return lane, a plurality of gas extraction pipelines are arranged in the large coal pillar, and the plurality of gas extraction pipelines are staggered with the chambers;
s3, performing roof cutting and pressure relief on the roof in the air inlet roadway of the stope face to form a cutting seam;
s4, stoping the stoping face to make the roof rock stratum collapse along the cutting seam to form a goaf;
s5, when the stoping working face is close to the underground chamber, grouting and filling the underground chamber in the stoping face air inlet roadway;
s6, after the stoped working face pushes a certain distance of a gas extraction pipeline, filling, plugging and cutting the gas extraction pipeline in the large coal pillar corresponding to the goaf in the replacing face return airway;
s7, tunneling a small coal pillar roadway at a certain distance from the stope mining line direction in the direction of the hole cutting of the replacing face until the small coal pillar roadway is communicated, so that the small coal pillar working face is changed from the large coal pillar working face to form a new replacing working face;
s8, mining the replacing working face along the small coal pillar roadway, wherein the small coal pillar roadway and the large coal pillar roadway are used as return air roadways until the mining of the working face is finished;
as an improvement on the technical scheme, the position of the small coal pillar roadway is opposite to the cutting position.
As an improvement to the above technical solution, the large coal pillar refers to a coal pillar with a width of ≧ 20 m; the small coal pillar is a coal pillar with the width of 3-8 m; and the replacing surface return airway is formed by an original large coal pillar airway.
As an improvement on the above technical solution, in the step S3, the method for cutting the top and releasing the pressure includes energy-gathered blasting top cutting, hydraulic pressure top cutting, hydraulic cutting top cutting, and expanding agent top cutting.
As an improvement on the above technical solution, in S3, after the roof cutting and pressure relief is completed, the roof cutting effect needs to be inspected, and the inspection methods include, but are not limited to, direct observation, borehole peeping observation, borehole pressurized-water observation, and surrounding rock stress monitoring.
As an improvement to the above technical solution, the grouting filling of the chamber in step S5 includes, but is not limited to, a fly ash filling, a foam cement filling, a concrete filling, and a high-water material filling.
As an improvement to the above technical solution, in step S6, the filling area of the gas extraction pipeline is an area corresponding to the small coal pillar, and the cutting area is a small coal pillar roadway area.
As an improvement to the above technical solution, in the step S7, the small coal pillar roadway should be tunneled after the gob is stabilized, and the tunneling direction of the small coal pillar roadway is the same as the advancing direction of the working face.
As an improvement to the above technical solution, in step S7, a local ventilator is used for supplying air for the small coal pillar roadway, and the dirty air enters the large coal pillar roadway (return airway) through the driving face and the small coal pillar roadway.
As an improvement on the technical scheme, in the step S7, the small and medium coal pillar tunnels are assisted to be transported by a mine car or a trackless rubber-tyred vehicle to reach the tunneling working face from the large coal pillar tunnel and the small coal pillar tunnel; coal gangue in the small coal pillar tunnel is transported by a belt and enters the air inlet tunnel of the replacing working face from the driving working face through the small coal pillar tunnel and the cut hole of the replacing working face.
Compared with the prior art, the invention has the beneficial effects that:
compared with the working surface of the existing large coal pillar roadway, the distributed large coal pillar roadway can be changed into the working surface of the small coal pillar roadway, so that the resource waste can be reduced, and the extraction rate can be improved; compared with the working surface of the existing small coal pillar roadway, the roof cutting and pressure relief are carried out on the air inlet roadway roof of the stope face, the structure and the stress distribution state of surrounding rocks can be changed, roof rock stratum collapse and goaf stabilization are accelerated, and the tunneling time of the coal pillar roadway after the goaf is stabilized is shortened; according to the invention, the chamber is filled in the air inlet roadway of the stope face, so that the coal pillar of the small coal pillar roadway is prevented from narrowing and destabilizing, and the stability of the small coal pillar roadway is improved; according to the invention, the gas extraction pipeline is plugged in the stope face air inlet roadway, so that the communication between the small coal pillar roadway and the goaf is avoided, and the safety of the small coal pillar roadway is improved; according to the invention, the gas extraction pipeline is cut in the air inlet roadway of the stope face, so that the contact between the heading machine and the gas pipeline in the heading process of the small coal pillar roadway is avoided, and the heading safety is improved.
Drawings
FIG. 1 is a schematic plan view of a working surface arrangement of the present invention;
FIG. 2 is a schematic cross-sectional view of the working face arrangement of the present invention;
FIG. 3 is a schematic of the inventive topping relief;
FIG. 4 is a schematic view of the chamber filling of the present invention;
FIG. 5 is a schematic view of a goaf caving structure of the present invention;
FIG. 6 is a schematic plan view of the filling and cutting of the gas extraction pipeline of the present invention;
FIG. 7 is a schematic cross-sectional view of a filling and cutting of a gas extraction pipeline according to the present invention;
FIG. 8 is a schematic plan view of the small coal pillar driving of the present invention;
FIG. 9 is a schematic view of a small coal pillar tunneling through plane of the present invention;
FIG. 10 is a schematic view of the small coal pillar driving section of the present invention;
fig. 11 is a schematic drawing of a mining plane of a working surface of a large coal pillar roadway changed into a small coal pillar roadway according to the invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-11, an embodiment of the present invention:
the mining method of changing the large coal pillar working face into the small coal pillar working face adopted by the invention firstly needs to form a stope working face 1 and a replacing working face 2, and a large coal pillar 3 (more than 20 m) is arranged between the working faces. As shown in fig. 1 and 2, the method for forming the stope face and the replacement face is the same as the existing method, the stope face comprises a stope face cutting hole 4, a stope face air inlet lane 5 and a stope face air return lane 6, the stope face air return lane comprises a plurality of chambers 7, the replacement face comprises a replacement face cutting hole 8, a replacement face air inlet lane 9 and a replacement face air return lane 10 (a large coal pillar lane), and a plurality of gas extraction pipelines 11 are arranged in a large coal pillar.
As shown in fig. 3, roof cutting and pressure relief are carried out on the roof in the stope face air intake roadway 5 by means of energy-gathering blasting, hydraulic pressure, hydraulic cutting, expanding agents and the like to form a weak structural face 12, after roof cutting and pressure relief, roof cutting effects are checked by means of direct observation, drill hole peeking, drill hole water pressing, surrounding rock stress monitoring and the like in time, after stope face stoping is finished, the roof collapses along the weak structural face in time, surrounding rock structures are changed, surrounding rock stress is reduced, and favorable conditions are created for small coal pillar roadways.
As shown in fig. 4 and 5, the stope face stopes, and the roof collapses along the cutting seam to form a gob 13; as shown in fig. 4 and 5, when the stope face approaches the chamber 7, the chamber 7 is filled with fly ash, foamed cement, concrete or high-water material in the stope face air inlet lane 5, so as to prevent coal pillar instability caused by the narrow width of the small coal pillar.
As shown in fig. 6 and 7, when the stope face pushes through the gas extraction pipeline, the gas extraction pipeline in the coal pillar is subjected to filling, plugging and cutting 15 in the stope face return airway 10.
As shown in fig. 8, 9 and 10, a small coal pillar roadway 16 is excavated in the direction of the stope line from the cut hole 8 of the take-over working surface to the stope working surface at a certain distance, and the width of the small coal pillar 17 is 3-8m until the small coal pillar roadway is communicated, so that the small coal pillar roadway is changed from the large coal pillar roadway to form a new small coal pillar roadway working surface 18.
As shown in fig. 11, the working face 18 of the small pillar roadway is mined along the small pillar roadway, and the small pillar roadway and the large pillar roadway are used as return air roadways until mining of the working face is completed.
Compared with the working surface of the existing large coal pillar roadway, the distributed large coal pillar roadway can be changed into the working surface of the small coal pillar roadway, so that the resource waste can be reduced, and the extraction rate can be improved; compared with the working surface of the existing small coal pillar roadway, the roof cutting and pressure relief are carried out on the top plate of the air intake roadway of the stope face, the structure and the stress distribution state of surrounding rocks can be changed, collapse of the top rock stratum and stability of a goaf are accelerated, and the tunneling time of the coal pillar roadway after the goaf is stabilized is shortened; according to the invention, the chamber is filled in the air inlet roadway of the stope face, so that the coal pillar of the small coal pillar roadway is prevented from narrowing and destabilizing, and the stability of the small coal pillar roadway is improved; according to the invention, the gas extraction pipeline is plugged in the stope face air inlet roadway, so that the communication between the small coal pillar roadway and the goaf is avoided, and the safety of the small coal pillar roadway is improved; according to the invention, the gas extraction pipeline is cut in the air inlet roadway of the stope face, so that the contact between the heading machine and the gas pipeline in the heading process of the small coal pillar roadway is avoided, and the heading safety is improved.
Claims (10)
1. A mining method for changing a large coal pillar working face into a small coal pillar working face is characterized by comprising the following steps:
the method comprises the following steps that S1, two working faces, namely a stope working face and a take-over working face, are arranged on a coal seam, and the stope working face and the take-over working face are respectively arranged on two sides of a large coal pillar;
s2, the stope face is provided with a stope face hole cutting lane, a stope face air inlet lane and a stope face air return lane, and a plurality of chambers are arranged on the side of a large coal pillar close to one side of the stope face air inlet lane; the replacing working face is provided with a replacing face hole cutting roadway, a replacing face air inlet roadway and a replacing face air return roadway, a plurality of gas extraction pipelines are arranged in the large coal pillar, and the plurality of gas extraction pipelines are staggered with the plurality of chambers;
s3, performing roof cutting and pressure relief on the roof in the air inlet roadway of the stope face to form a cutting seam;
s4, stoping the stoping face to make the roof rock stratum collapse along the cutting seam to form a goaf;
s5, when the stoping working face is close to the chamber, grouting and filling the chamber in the stoping face air inlet roadway;
s6, after the stoping working face pushes a certain distance through the gas extraction pipelines, filling, blocking and cutting the gas extraction pipelines in the large coal pillar corresponding to the goaf in the stoping face return airway;
s7, tunneling a small coal pillar roadway at a certain distance from the stope mining line direction in the direction of the hole cutting of the replacing face until the small coal pillar roadway is communicated, so that the small coal pillar working face is changed from the large coal pillar working face to form a new replacing working face;
and S8, mining the replacing working face along the small coal pillar roadway, wherein the small coal pillar roadway and the large coal pillar roadway are used as return air roadways until the mining of the working face is finished.
2. The mining method for changing the large coal pillar working face into the small coal pillar working face according to claim 1, characterized in that: the position of the small coal pillar roadway is opposite to the cutting position.
3. The mining method for changing the large coal pillar working face into the small coal pillar working face according to claim 1, characterized in that: the large coal pillar is a coal pillar with the width being equal to or larger than 20 m; the small coal pillar refers to a coal pillar with the width of 3-8 m; and the replacing surface return airway is formed by an original large coal pillar airway.
4. The mining method for changing the large coal pillar working face into the small coal pillar working face according to claim 1, characterized in that: in the step S3, the method for cutting the top and relieving the pressure comprises energy-gathered blasting top cutting, hydraulic pressure top cutting, hydraulic cutting top cutting and expanding agent top cutting.
5. The mining method for changing the large coal pillar working face into the small coal pillar working face according to claim 1, characterized in that: in S3, after roof cutting and pressure relief are completed, roof cutting effects need to be checked, and the checking method comprises but is not limited to direct observation, borehole peeping observation, borehole water pressing observation and surrounding rock stress monitoring.
6. The mining method for changing the large coal pillar working face into the small coal pillar working face according to claim 1, characterized in that: the grouting filling of the chamber in the step S5 comprises but is not limited to fly ash filling, foaming cement filling, concrete filling and high-water material filling.
7. The mining method for changing the large coal pillar working face into the small coal pillar working face according to claim 1, characterized in that: in the step S6, the filling area of the gas extraction pipeline is the area corresponding to the small coal pillar, and the cutting area is the small coal pillar roadway area.
8. The mining method for changing the large coal pillar working face into the small coal pillar working face according to claim 1, characterized in that: in the step S7, the small coal pillar roadway excavation is carried out after the goaf is stabilized, and the small coal pillar roadway excavation direction is the same as the working face advancing direction.
9. The mining method for changing the large coal pillar working face into the small coal pillar working face according to claim 1, characterized in that: in the step S7, the small coal pillar roadway is tunneled and ventilated by adopting a local ventilator to supply air, and dirty air enters the large coal pillar roadway through the tunneling working face and the small coal pillar roadway.
10. The mining method for changing the large coal pillar working face into the small coal pillar working face as claimed in claim 1, wherein in the step S7, the small and medium coal pillar roadway is assisted by a mine car or a trackless rubber-tyred car to reach the driving face from the large coal pillar roadway and the small coal pillar roadway; coal gangue in the small coal pillar tunnel is transported by a belt and enters the air inlet tunnel of the replacing working face from the driving working face through the small coal pillar tunnel and the replacing working face undercut.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210943537.6A CN115434706A (en) | 2022-08-08 | 2022-08-08 | Mining method for changing large coal pillar working face into small coal pillar working face |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210943537.6A CN115434706A (en) | 2022-08-08 | 2022-08-08 | Mining method for changing large coal pillar working face into small coal pillar working face |
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| Publication Number | Publication Date |
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| CN115434706A true CN115434706A (en) | 2022-12-06 |
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| CN202210943537.6A Pending CN115434706A (en) | 2022-08-08 | 2022-08-08 | Mining method for changing large coal pillar working face into small coal pillar working face |
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- 2022-08-08 CN CN202210943537.6A patent/CN115434706A/en active Pending
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