CN112922665A - Construction method for treating abnormal gas emission in low-gas mine goaf by high-level drainage - Google Patents
Construction method for treating abnormal gas emission in low-gas mine goaf by high-level drainage Download PDFInfo
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- CN112922665A CN112922665A CN202110068631.7A CN202110068631A CN112922665A CN 112922665 A CN112922665 A CN 112922665A CN 202110068631 A CN202110068631 A CN 202110068631A CN 112922665 A CN112922665 A CN 112922665A
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- 238000010276 construction Methods 0.000 title claims abstract description 27
- 230000002159 abnormal effect Effects 0.000 title claims abstract description 19
- 239000003245 coal Substances 0.000 claims abstract description 27
- 238000005553 drilling Methods 0.000 claims abstract description 17
- 239000002002 slurry Substances 0.000 claims abstract description 10
- 238000000034 method Methods 0.000 claims abstract description 8
- 238000007789 sealing Methods 0.000 claims abstract description 4
- 238000005065 mining Methods 0.000 claims description 7
- 239000012530 fluid Substances 0.000 claims description 6
- 239000004568 cement Substances 0.000 claims description 3
- 238000000605 extraction Methods 0.000 claims description 3
- 230000000737 periodic effect Effects 0.000 claims description 3
- 235000019353 potassium silicate Nutrition 0.000 claims description 3
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims description 3
- 238000004880 explosion Methods 0.000 claims description 2
- 231100000331 toxic Toxicity 0.000 claims 1
- 230000002588 toxic effect Effects 0.000 claims 1
- 238000009423 ventilation Methods 0.000 abstract description 7
- 238000009825 accumulation Methods 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 4
- 230000009286 beneficial effect Effects 0.000 abstract 1
- 239000007788 liquid Substances 0.000 abstract 1
- 238000004519 manufacturing process Methods 0.000 description 5
- 230000001174 ascending effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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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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- 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
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B34/00—Valve arrangements for boreholes or wells
- E21B34/02—Valve arrangements for boreholes or wells in well heads
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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
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/006—Production of coal-bed methane
-
- 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
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/12—Methods or apparatus for controlling the flow of the obtained fluid to or in wells
- E21B43/121—Lifting well fluids
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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
- E21B7/00—Special methods or apparatus for drilling
- E21B7/04—Directional drilling
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- Engineering & Computer Science (AREA)
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- Life Sciences & Earth Sciences (AREA)
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- Geochemistry & Mineralogy (AREA)
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- Environmental & Geological Engineering (AREA)
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- Physics & Mathematics (AREA)
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- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
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Abstract
The invention discloses a construction method for controlling abnormal gas emission in a low-gas mine goaf through high-position drainage, which comprises the steps of determining the height of a caving zone of a working face coal seam roof, determining the position of a high-position drainage final hole, determining the trend gradient of an upper smooth groove, designing a drill hole, sequentially arranging the final holes from the working face roof from bottom to top, arranging the projection positions of the final holes from the working face in a linear mode, arranging a hole at the shoulder pit of a stoping side of a roadway roof, sealing the hole through double-liquid slurry, installing a gate valve at the hole opening, arranging a gas sample observation hole at the inner side of the valve, and adopting a ground gas drainage pump for a mine. The invention has the beneficial effects that: the method has the advantages of reducing abnormal gas emission in the goaf caused by the collapse of the hard roof, effectively avoiding the generation of drilling friction flame in the goaf, having high construction safety, small drainage engineering quantity, good effect of treating the abnormal gas emission in the goaf of the low gas mine and the like, and solving the problem of gas accumulation on the coal face caused by the collapse of the hard roof of the coal face and the upward ventilation mode.
Description
Technical Field
The invention relates to the technical field of mines, in particular to a construction method for treating abnormal gas emission in a low-gas mine goaf by high-level drainage.
Background
In China, most of coal mining methods of working faces under coal mines adopt wall-type coal mining working faces, all caving methods manage top plates, most of the coal mining working face top plates are hard top plates, so that goaf top plates cannot be effectively caving in time, and an upward ventilation mode adopted by the wall-type coal mining working faces is adopted, so that the upward ventilation mode of the coal mining working faces has a quite obvious effect in the underground production of the coal mines, has the effects of simple production system, high yield, high efficiency, simplicity and convenience in operation in production, and has the unique advantages of stable air flow and less air leakage in the aspect of ventilation system safety, and therefore the arrangement of the upward ventilation mode of the coal mining working faces is a main arrangement method under the coal mines; the biggest defect of the wall-type coal face adopting the face ascending ventilation mode is that gas accumulation at the upper corner of the face (namely gas accumulation at the tail of a scraper conveyor) is easily caused when the top plate is poorly managed. If the hard top plate of the goaf collapses in a large area, gas at the upper corner of the coal face is accumulated, and gas explosion of the coal face seriously threatens the life safety of workers and the safety production under the coal mine, so that the method is a great hidden danger of the coal face and a great danger source, is a great problem which puzzles the safety production of the coal mine for a long time, and is a great problem of worldwide coal mine which is not really solved nationwide or even worldwide.
Disclosure of Invention
The invention aims to provide a construction method for treating abnormal gas emission in a low-gas mine goaf by high-level drainage so as to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: the construction method for treating abnormal gas emission in the low-gas mine goaf by high-level drainage comprises the following steps:
the method comprises the following steps: determining the height of a caving zone of a coal seam top plate of a working face to be 50.08 m;
step two: determining that the position of a final high-position drainage hole is not higher than 50 m;
step three: determining the trend gradient of the upper gate way to be 9 degrees;
step four: the periodic pressure step distance of the working face is 30 m;
step five: the preliminary caving height of the top plate after the extraction and the frame moving of the working face is 12 m;
step six: designing at least 3 drill holes in each group;
step seven: the final holes are arranged from bottom to top in sequence from the top plate of the working surface;
step eight: the projection position of the final hole is sequentially arranged in a linear manner from bottom to top at the upper corner from the working surface;
step nine: the drilling hole opening position is located at the position of a stoping slope shoulder pit of a roadway roof, and the final hole position is constructed 50 meters ahead of the working surface;
step ten: sealing holes through double fluid slurry, installing a gate valve at an orifice, and arranging a gas sample observation hole at the inner side of the valve;
step eleven: the mine adopts a ground gas drainage pump, uses a special gas drainage pipe, and is connected with 3 drainage holes at each time to drain the gas in the goaf.
Preferably, in the seventh step, the final hole is arranged at 27m, 37m and 47m from the bottom to the top plate of the working face in sequence.
Preferably, in the seventh step, the projection position of the final hole is located at 23m, 19m and 14m from bottom to top from the working surface.
Preferably, in the sixth step, the drilling depth is 120 m.
Preferably, in the sixth step, the three drilling inclination angles are 7 °, 12 ° and 17 ° in sequence, and the included angles with the center line of the roadway are 7 °, 9 °, and 11 ° in sequence from bottom to top.
Preferably, in the ninth step, the drilling hole position is located at the top plate of the stoping side shoulder pit of the roadway top plate, so that coal seam drainage drilling hole air leakage caused by pressure advance of the working face is avoided, and the front-back distance is 1.5 m.
Preferably, in the sixth step, a hole is drilled through a drill bit with the diameter of 113mm, and a sleeve with the diameter of 108mm is installed.
Preferably, in the step ten, the double-fluid slurry is cement slurry and water glass.
Preferably, in the eleventh step, the gas drainage pipe has a diameter of 160mm, and 3 drainage holes are formed in advance of 50 m.
Has the advantages that:
the construction method for treating abnormal gas emission in the low-gas mine goaf by high-level drainage provided by the invention reduces ironwork entering the goaf, effectively prevents friction flame in the goaf from being generated, has the advantages of high drainage concentration, large gas drainage amount, good treatment effect and the like, and solves the problem of gas accumulation on a coal face caused by an upward ventilation mode of the coal face.
Drawings
Fig. 1 is a schematic plan view of the present invention.
Detailed Description
The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.
Examples
As shown in fig. 1, the construction method for treating abnormal gas emission in the low-gas mine goaf by high-level drainage comprises the following steps:
the method comprises the following steps: determining the height of a caving zone of a coal seam top plate of a working face to be 50.08 m;
step two: determining that the position of a final high-position drainage hole is not higher than 50 m;
step three: determining the trend gradient of the upper gate way to be 9 degrees;
step four: the periodic pressure step distance of the working face is 30 m;
step five: the preliminary caving height of the top plate after the extraction and the frame moving of the working face is 12 m;
step six: designing at least 3 drill holes in each group;
step seven: the final holes are arranged from bottom to top in sequence from the top plate of the working surface;
step eight: the projection position of the final hole is sequentially arranged in a linear manner from bottom to top at the upper corner from the working surface;
step nine: the drilling hole opening position is located at the position of a stoping slope shoulder pit of a roadway roof, and the final hole position is constructed 50 meters ahead of the working surface;
step ten: sealing holes through double fluid slurry, installing a gate valve at an orifice, and arranging a gas sample observation hole at the inner side of the valve;
step eleven: the mine adopts a ground gas drainage pump, uses a special gas drainage pipe, and is connected with 3 drainage holes at each time to drain the gas in the goaf.
Preferably, in the seventh step, the final holes are arranged at 27m, 37m and 47m from the top plate of the working face in sequence from bottom to top.
Preferably, in the seventh step, the final hole projection positions are arranged at 23m, 19m and 14m from bottom to top from the working surface.
Preferably, in the sixth step, the drilling depth is 120 m.
Preferably, in the sixth step, the inclination angles of the three drill holes are 7 °, 12 ° and 17 ° in sequence, and the included angles with the central line of the roadway are 7 °, 9 °, and 11 ° in sequence from bottom to top.
Preferably, in the ninth step, the drilling hole position is located at the top plate of the stoping side shoulder pit of the roadway top plate, so that coal seam drainage drilling hole air leakage caused by pressure advance of the working face is avoided, and the front-back distance is 1.5 m.
Preferably, in step six, a hole is drilled through a drill bit with the diameter of 113mm, and a sleeve with the diameter of 108mm is installed.
Preferably, in the step ten, the double-fluid slurry is cement slurry and water glass.
Preferably, in the eleventh step, the gas drainage pipe with the diameter of 160mm is constructed, and 3 drainage holes are advanced by 50 m.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. The construction method for treating abnormal gas emission in the low-gas mine goaf by high-level drainage is characterized by comprising the following steps of:
the method comprises the following steps: determining the height of a caving zone of a coal seam top plate of a working face to be 50.08 m;
step two: determining that the position of a final high-position drainage hole is not higher than 50 m;
step three: determining the trend gradient of the upper gate way to be 9 degrees;
step four: the periodic pressure step distance of the working face is 30 m;
step five: the preliminary caving height of the top plate after the extraction and the frame moving of the working face is 12 m;
step six: designing at least 3 drill holes in each group;
step seven: the final holes are arranged from bottom to top in sequence from the top plate of the working surface;
step eight: the projection position of the final hole is sequentially arranged in a linear manner from bottom to top at the upper corner from the working surface;
step nine: the drilling hole opening position is located at the position of a stoping slope shoulder pit of a roadway roof, and the final hole position is constructed 50 meters ahead of the working surface;
step ten: sealing holes through double fluid slurry, installing a gate valve at an orifice, and arranging a gas sample observation hole at the inner side of the valve;
step eleven: the mine adopts a ground gas drainage pump, uses a special gas drainage pipe, and is connected with 3 drainage holes at each time to drain the gas in the goaf.
2. The construction method for treating abnormal gas emission in the goaf of the low-gas mine by high-level drainage according to claim 1, wherein the construction method comprises the following steps: and seventhly, arranging the final hole distance from the working face top plate to 27m, 37m and 47m in sequence from bottom to top.
3. The construction method for treating abnormal gas emission in the goaf of the low-gas mine by high-level drainage according to claim 1, wherein the construction method comprises the following steps: and in the seventh step, the projection position of the final hole is arranged at positions 23m, 19m and 14m from bottom to top from the working surface.
4. The construction method for treating abnormal gas emission in the goaf of the low-gas mine by high-level drainage according to claim 1, wherein the construction method comprises the following steps: in the sixth step, the drilling depth is 120 m.
5. The construction method for treating abnormal gas emission in the goaf of the low-gas mine by high-level drainage according to claim 1, wherein the construction method comprises the following steps: in the sixth step, the three drilling inclination angles are 7 degrees, 12 degrees and 17 degrees in sequence, and the included angles between the three drilling inclination angles and the center line of the roadway are 7 degrees, 9 degrees and 11 degrees from bottom to top in sequence.
6. The construction method for treating abnormal gas emission in the goaf of the low-gas mine by high-level drainage according to claim 1, wherein the construction method comprises the following steps: in the ninth step, the drilling hole position is located at the position of the top plate of the roadway mining slope shoulder pit, so that coal seam drainage drilling hole air leakage caused by pressure advance of a working face is avoided, and the front-back distance is 1.5 m.
7. The construction method for treating abnormal gas emission in the goaf of the low-gas mine by high-level drainage according to claim 1, wherein the construction method comprises the following steps: and in the sixth step, a hole is formed through a drill bit with the diameter of 113mm, and a sleeve with the diameter of 108mm is installed.
8. The construction method for treating abnormal gas emission in the goaf of the low-gas mine by high-level drainage according to claim 1, wherein the construction method comprises the following steps: in the step ten, the double-fluid slurry is cement slurry and water glass.
9. The construction method for treating abnormal gas emission in the goaf of the low-gas mine by high-level drainage according to claim 1, wherein the construction method comprises the following steps: in the eleventh step, the gas drainage pipe with the diameter of 160mm is constructed by leading the final holes of 3 drainage holes to be 50m ahead of the working surface, so that the possibility of explosion when the gas enters the goaf during drilling construction or the toxic and harmful gas in the goaf overflows along the drilled hole during withdrawal of the drill is avoided.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110068631.7A CN112922665A (en) | 2021-01-19 | 2021-01-19 | Construction method for treating abnormal gas emission in low-gas mine goaf by high-level drainage |
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| CN202110068631.7A CN112922665A (en) | 2021-01-19 | 2021-01-19 | Construction method for treating abnormal gas emission in low-gas mine goaf by high-level drainage |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3934649A (en) * | 1974-07-25 | 1976-01-27 | The United States Of America As Represented By The United States Energy Research And Development Administration | Method for removal of methane from coalbeds |
| US4978172A (en) * | 1989-10-26 | 1990-12-18 | Resource Enterprises, Inc. | Gob methane drainage system |
| CN103775127A (en) * | 2013-12-31 | 2014-05-07 | 中国矿业大学 | Method for comprehensively treating gas in low-air-permeability high-gas-content coal seam group |
| CN109339856A (en) * | 2018-11-29 | 2019-02-15 | 陕西陕煤铜川矿业有限公司 | A kind of method that face gas is administered |
| CN111577282A (en) * | 2020-05-26 | 2020-08-25 | 内蒙古福城矿业有限公司 | High-low negative pressure separate source coal mine gas drainage process |
-
2021
- 2021-01-19 CN CN202110068631.7A patent/CN112922665A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3934649A (en) * | 1974-07-25 | 1976-01-27 | The United States Of America As Represented By The United States Energy Research And Development Administration | Method for removal of methane from coalbeds |
| US4978172A (en) * | 1989-10-26 | 1990-12-18 | Resource Enterprises, Inc. | Gob methane drainage system |
| CN103775127A (en) * | 2013-12-31 | 2014-05-07 | 中国矿业大学 | Method for comprehensively treating gas in low-air-permeability high-gas-content coal seam group |
| CN109339856A (en) * | 2018-11-29 | 2019-02-15 | 陕西陕煤铜川矿业有限公司 | A kind of method that face gas is administered |
| CN111577282A (en) * | 2020-05-26 | 2020-08-25 | 内蒙古福城矿业有限公司 | High-low negative pressure separate source coal mine gas drainage process |
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Inventor after: Du Zhilong Inventor after: Zhang Jingmin Inventor after: Liu Binbin Inventor after: Meng Fanlin Inventor after: Zhao Fei Inventor after: Xiang Dongdong Inventor after: Mao Fengfeng Inventor after: Wang Shoujun Inventor after: Liu Mingsong Inventor after: Hao Liangpeng Inventor after: Han Tieliang Inventor after: Yang Zhiqiang Inventor after: Mao Chaohui Inventor after: Ren Nan Inventor after: Guo Zhenghua Inventor before: Du Zhilong Inventor before: Zhang Jingmin Inventor before: Meng Fanlin Inventor before: Zhao Fei Inventor before: Xiang Dongdong Inventor before: Wang Shoujun Inventor before: Liu Mingsong Inventor before: Hao Liangpeng Inventor before: Han Tieliang Inventor before: Yang Zhiqiang Inventor before: Mao Chaohui Inventor before: Ren Nan Inventor before: Guo Zhenghua |
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Application publication date: 20210608 |
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