CN117803443A - Close range coal seam mining gas control method based on roof-floor rock stratum breaking characteristics - Google Patents
Close range coal seam mining gas control method based on roof-floor rock stratum breaking characteristics Download PDFInfo
- Publication number
- CN117803443A CN117803443A CN202311765594.0A CN202311765594A CN117803443A CN 117803443 A CN117803443 A CN 117803443A CN 202311765594 A CN202311765594 A CN 202311765594A CN 117803443 A CN117803443 A CN 117803443A
- Authority
- CN
- China
- Prior art keywords
- coal seam
- level
- level coal
- low
- gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003245 coal Substances 0.000 title claims abstract description 319
- 238000005065 mining Methods 0.000 title claims abstract description 48
- 238000000034 method Methods 0.000 title claims abstract description 14
- 239000011435 rock Substances 0.000 title claims abstract description 12
- 239000007789 gas Substances 0.000 claims abstract description 124
- 238000000605 extraction Methods 0.000 claims abstract description 50
- 239000002737 fuel gas Substances 0.000 claims abstract description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 24
- 238000005452 bending Methods 0.000 claims description 7
- 238000010276 construction Methods 0.000 claims description 6
- 238000010248 power generation Methods 0.000 claims description 6
- 230000000149 penetrating effect Effects 0.000 claims description 4
- 230000000694 effects Effects 0.000 abstract description 16
- 230000005611 electricity Effects 0.000 abstract description 4
- 239000010410 layer Substances 0.000 description 32
- 238000005553 drilling Methods 0.000 description 12
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000005755 formation reaction Methods 0.000 description 4
- 239000011241 protective layer Substances 0.000 description 4
- 230000035699 permeability Effects 0.000 description 3
- 238000009933 burial Methods 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Landscapes
- Solid Fuels And Fuel-Associated Substances (AREA)
Abstract
The invention belongs to the field of coal mine gas control, and particularly relates to a near-distance coal seam mining gas control method based on a fracture characteristic of a roof-floor rock stratum. According to the invention, the pressure relief condition of the bottom plate of the high-level coal seam exploitation and the pressure relief condition of the top plate of the low-level coal seam exploitation are fully considered, and a reasonable coal seam exploitation sequence and a gas extraction scheme are provided according to the relative position relationship of the high-level coal seam and the low-level coal seam, so that effective gas pressure relief is generated on the other coal seam after one coal seam is exploited, and the gas treatment effect can be improved by better utilizing the mining sequence relationship among the coal seams. The gas treatment effect is improved maximally on the premise of not increasing extra treatment cost, and the gas hazard is reduced. Meanwhile, the extracted gas is used for generating electricity or used as fuel gas after being treated, so that the greenhouse effect generated by the gas can be reduced and the resource utilization rate can be improved.
Description
Technical Field
The invention belongs to the field of coal mine gas control, and particularly relates to a near-distance coal seam mining gas control method based on a fracture characteristic of a roof-floor rock stratum.
Background
The mining of the protective layer is an important means for preventing and controlling the gas in the low-permeability coal seam, and the pressure relief is generated on the upper coal rock layer and the lower coal rock layer after the mining of the protective layer, so that the gas permeability of the coal seam in the pressure relief range is increased, and the gas in the coal seam is converted from an adsorption state to a free state. Therefore, for the close-range coal seam, if one layer of the coal seam can be utilized to mine the other layer of the coal seam to generate a pressure relief effect (the other layer of the coal seam is firstly mined), so that the air permeability of the coal seam is increased, the gas extraction efficiency in the coal seam can be greatly improved, and the gas treatment is facilitated. However, when the existing close-range coal seam is mined, the mining sequence is not planned, so that the gas pressure relief effect of one layer of coal seam is not ideal (the other layer of coal seam is mined later and is protected), and a large amount of gas treatment work is needed to be carried out on the other layer of the coal seam subjected to pressure relief later.
Disclosure of Invention
Aiming at the problem that the pressure relief effect of the protective layer is not ideal due to the lack of planning of the mining sequence during the existing close-range coal seam mining, the invention fully considers the pressure relief condition of the high-level coal seam mining bottom plate and the pressure relief condition of the low-level coal seam mining top plate, and provides a reasonable coal seam mining sequence and a gas extraction scheme so as to effectively relieve the pressure of gas on the other coal seam after one coal seam is mined. Specifically, the near-distance coal seam mining gas treatment method based on the fracture characteristics of the roof and floor strata provided by the invention comprises the following steps:
(1) Determining the range of a bottom plate longitudinal guide passband and a bottom plate transverse fracture passband during high-level coal seam mining;
(2) Determining the range of a caving zone and a water guide fracture zone during low-level coal seam exploitation;
(3) If the high-level coal seam is positioned in the caving zone of the low-level coal seam;
3.1 When the low-level coal seam is positioned in the bottom plate longitudinal guide passband of the high-level coal seam, arranging a return air gate and a transportation gate in the high-level coal seam, connecting the return air gate and the transportation gate through a coal face, forming a goaf after coal mining by the coal face, forming a return air gate along a gob-side entry at the return air gate, and performing gas extraction on the goaf from the return air gate;
3.2 Or when the low-level coal seam is positioned in a transverse fracture zone of the bottom plate of the high-level coal seam, arranging a return air cis-slot and a transportation cis-slot in the high-level coal seam, connecting the return air cis-slot and the transportation cis-slot through a coal face, forming a goaf after coal mining by the coal face, forming a transportation drift along a gob-side entry retaining at the transportation cis-slot, and performing gas extraction from the transportation drift to a layer penetrating drill hole for low-level coal seam construction;
(4) If the high-level coal seam is positioned in the water guide fracture zone of the low-level coal seam;
4.1 When the low-level coal seam is positioned in the bottom plate longitudinal guide passband of the high-level coal seam, constructing a gas extraction roadway parallel to the advancing direction of the low-level coal seam in the range of the water guide fracture zone of the low-level coal seam at a certain position at the upper part of the high-level coal seam, and simultaneously extracting the gas generated in the low-level coal seam and the high-level coal seam by using the gas extraction roadway;
4.2 Or when the low-level coal seam is positioned in a transverse fracture zone of the bottom plate of the high-level coal seam, arranging a return air cis-slot and a transportation cis-slot in the high-level coal seam, connecting the return air cis-slot and the transportation cis-slot through a coal face, forming a goaf after coal mining by the coal face, forming a transportation drift along a gob-side entry retaining at the transportation cis-slot, and performing gas extraction from the transportation drift to a layer penetrating drill hole for low-level coal seam construction;
(5) If the high-level coal seam is positioned in the bending subsidence zone of the low-level coal seam;
5.1 When the low-level coal seam is positioned in a transverse fracture zone of a bottom plate of the high-level coal seam, arranging a return air cis-slot and a transportation cis-slot in the high-level coal seam, connecting the return air cis-slot and the transportation cis-slot through a coal face, forming a goaf after coal mining by the coal face, forming a transportation drift along a gob-side entry retaining at the transportation cis-slot, and performing gas extraction from the transportation drift retaining to a layer-penetrating drill hole in the low-level coal seam construction;
5.2 Or if the horizontal fracture zone of the bottom plate of the high-level coal bed is deep, pre-fracturing the high-level coal bed and the rock stratum near the top and bottom plates of the high-level coal bed, so that the water guiding fracture zone can develop to a certain position above the high-level coal bed when the low-level coal bed is mined; and constructing a gas extraction roadway on the upper part of the high-level coal seam in parallel to the advancing direction of the low-level coal seam, firstly mining the low-level coal seam, and simultaneously extracting the gas generated in the low-level coal seam and the high-level coal seam by using the gas extraction roadway.
Preferably, in the step 3.1), a bedding drill hole is constructed from the return air retaining roadway into the goaf, and a drainage screen pipe is arranged in the bedding drill hole to conduct gas drainage.
Preferably, in the steps 3.2), 4.2) and 5.1), the through-layer drilling holes penetrate through the transverse fracture zone of the bottom plate to reach the low-level coal bed, and the extraction sieve tube is arranged in the through-layer drilling holes.
Preferably, in step 4.1), the gas extraction roadway is located outside the caving zone of the high-level coal seam, and when the high-level coal seam is recovered, the gas extraction roadway is continuously used for extracting gas when the high-level coal seam is recovered.
Preferably, the extracted gas is treated for power generation or used as fuel gas.
Preferably, the coal seam is mined first and then gas is extracted before mining.
The beneficial technical effects of the invention are as follows: according to the invention, the pressure relief condition of the bottom plate of the high-level coal seam exploitation and the pressure relief condition of the top plate of the low-level coal seam exploitation are fully considered, and a reasonable coal seam exploitation sequence and a gas extraction scheme are provided according to the relative position relationship of the high-level coal seam and the low-level coal seam, so that effective gas pressure relief is generated on the other coal seam after one coal seam is exploited, and the gas treatment effect can be improved by better utilizing the mining sequence relationship among the coal seams. The gas treatment effect is improved maximally on the premise of not increasing extra treatment cost, and the gas hazard is reduced. Meanwhile, the extracted gas is used for generating electricity or used as fuel gas after being treated, so that the greenhouse effect generated by the gas can be reduced and the resource utilization rate can be improved.
Drawings
FIG. 1 is a schematic cross-sectional view of a propensity for pressure relief of a coal formation below a high seam mining floor;
FIG. 2 is a schematic cross-sectional view of a propensity for pressure relief of a coal formation above a roof of a low seam mining;
FIG. 3 is a schematic plan view of the return air gate gob-side entry retaining gas abatement;
FIG. 4 is a schematic plan view of a transportation gate gob-side entry retaining gas abatement;
FIG. 5 is a schematic cross-sectional view of a gas drainage trend using a drainage roadway;
FIG. 6 is a schematic cross-sectional view of gas drainage tendencies using drainage roadways after pre-fracturing the formation;
in the figure, a high-level coal seam 1; the bottom plate longitudinally guides the passband 2; a bottom plate transverse slit belt 3; a low-level coal seam 4; a landing strip 5; a water-guiding slit tape 6; a return air cis-slot 7; a transportation gate 8; a coal face 9; a goaf 10; a return air retaining roadway 11; a transport entry 12; a bedding borehole 13; a through-layer borehole 14; and (5) extracting a roadway 15.
Detailed Description
Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
Aiming at the problem that the pressure relief effect of the protective layer is not ideal due to the lack of planning of the mining sequence during the existing close-range coal seam mining, the invention fully considers the pressure relief condition of the mining bottom plate of the high-level coal seam 1 and the pressure relief condition of the mining top plate of the low-level coal seam 2, and provides a reasonable coal seam mining sequence and a gas extraction scheme so as to effectively relieve the pressure of gas on the other coal seam after one coal seam is mined. Specifically, the near-distance coal seam mining gas treatment method based on the fracture characteristics of the roof and floor strata provided by the invention comprises the following steps:
(1) Determining the pressure relief condition of the bottom plate during the exploitation of the high-level coal seam 1, as shown in fig. 1, including determining the range of the bottom plate longitudinal guide passband 2 and the bottom plate transverse fracture passband 3 during the exploitation of the high-level coal seam 1; the bottom plate rock layer is relieved after the high-level coal seam 1 is mined, the bottom plate rock layer close to the high-level coal seam is greatly influenced by mining stress, the damage degree is large, longitudinal cracks are generated and can be conducted to a high-level coal seam goaf, and the bottom plate longitudinal guide passband 2 is formed; the bottom plate relatively far from the high-level coal seam 1 can release pressure in a certain range, but does not generate longitudinal cracks or generates only a small amount of longitudinal cracks, but does not conduct the high-level coal seam goaf, but generates transverse cracks due to the pressure release effect, and the transverse cracks are not conducted with the high-level coal seam goaf, so that the bottom plate transverse crack zone 3 is formed; the ranges of the bottom plate longitudinal guide passband 2 and the bottom plate transverse fracture passband 3 can be determined by theoretical calculation according to the stratum condition (thickness and burial depth of each stratum, lithology and strength parameters, coal seam exploitation range and the like) of the coal seam, can also be determined by adopting a numerical simulation means, or can be determined by actual measurement, or can be estimated and determined by referring to an empirical formula given by the prior art. In fig. 1, the positional relationship between the low-level coal seam 4 and the high-level coal seam 1 is merely illustrative, and the low-level coal seam 4 may be located within the floor longitudinal guide passband 2 or the floor transverse fracture zone 3 of the high-level coal seam 1.
(2) Determining the pressure relief condition of the roof when the low-level coal seam 2 is mined, as shown in fig. 2, including determining the ranges of a roof caving zone 5 and a water guiding fracture zone 6 when the low-level coal seam 2 is mined; the roof strata is relieved after the low-level coal seam 2 is mined, and the roof strata close to the low-level coal seam 2 collapses and breaks into small irregular rock blocks, namely a caving belt 5; the roof relatively far away from the low-level coal seam 2 forms a water guide fracture zone 6 on the caving zone 5, the stratum in the water guide fracture zone 6 is broken regularly, longitudinal fractures exist in the water guide fracture zone to conduct the low-level coal seam goaf, the water guide fracture zone 6 is a bending subsidence zone from the ground surface, and longitudinal fractures which conduct the low-level coal seam goaf do not exist in the water guide fracture zone. The caving zone 5, the water guiding fracture zone 6 and the bending subsidence zone are the upper three zone features of the overburden collapse of the coal mining and are well known and will not be described in detail herein. The caving zone 5, the water-guiding fracture zone 6 and the bending subsidence zone can be determined in various ways according to theoretical calculation of the stratum where the coal seam is located (thickness and burial depth of each stratum, lithology and strength parameters, coal seam exploitation range and the like), or by adopting a numerical simulation means, or by actually measuring, or by referring to a formula given by the prior art for estimation. In fig. 2, the positional relationship between the low-level coal seam 4 and the high-level coal seam 1 is merely illustrative, and the high-level coal seam 1 may be located in a caving zone 5 or a water guiding fracture zone 6 of the high-level coal seam 1, and the high-level coal seam 1 in fig. 2 is located in a bending subsidence zone of the low-level coal seam 4.
(3) If the high-level coal seam 1 is positioned in the caving zone 4 of the low-level coal seam 4, the high-level coal seam 1 is mined firstly;
at this time, when the low-level coal seam 4 is located in the bottom plate longitudinal guide passband 2 of the high-level coal seam 1, as shown in fig. 3, an air return gate 7 and a transportation gate 8 are arranged in the high-level coal seam 1, the air return gate 7 and the transportation gate 8 are connected through a coal face 9, a goaf 10 is formed after coal mining by the coal face, an air return entry 11 is formed at the air return gate 7 along an empty entry, a gate hole 13 is constructed in the goaf 10 from the air return entry 11, and a drainage screen pipe is arranged in the gate hole 13. The gas overflowed after the pressure relief of the low-level coal seam 4 reaches the goaf of the high-level coal seam 1 after passing through the longitudinal conduction slot in the longitudinal guide passband 2 of the bottom plate, the gas overflowed after the pressure relief of the low-level coal seam 4 is extracted from the goaf 10 through the extraction sieve tube, and the extracted gas can be used for power generation or used as fuel gas after being treated;
at this time, when the low-level coal seam 4 is located in the bottom plate transverse fracture zone 3 of the high-level coal seam 1, as shown in fig. 4, an air return gate 7 and a transportation gate 8 are arranged in the high-level coal seam 1, the air return gate 7 and the transportation gate 8 are connected through a coal face 9, a goaf 10 is formed after coal mining of the coal face, a gob-side entry retaining is carried out at the transportation gate 8 to form a transportation entry retaining way 12, a through-layer drilling 14 is constructed from the transportation entry retaining way 12 to the low-level coal seam 4, the through-layer drilling 14 penetrates through the bottom plate transverse fracture zone 3 to reach the low-level coal seam 4, a drainage screen pipe is arranged in the through-layer drilling 14, gas generated by pressure relief of the low-level coal seam 4 in the bottom plate transverse fracture zone 3 is drained through the drainage screen pipe, and the drained gas can be used for power generation or as gas after being processed;
the high level coal seam 1 is positioned in the caving zone 4 of the low level coal seam 4, which means that two layers of coal are very close to each other, and the situation that the low level coal seam 4 is positioned in the transverse fracture zone 3 of the bottom plate of the high level coal seam 1 is deep is almost impossible.
(4) If the high-level coal seam 1 is positioned in the water guide fracture zone 6 of the low-level coal seam 4;
at this time, when the low-level coal seam 4 is located in the bottom plate longitudinal guide passband 2 of the high-level coal seam 1, as shown in fig. 5, the low-level coal seam 4 is firstly mined, a certain position is located at the upper part of the high-level coal seam 1 (as far as possible, the high-level coal seam 1 is located outside the caving zone), a gas extraction roadway 15 is constructed in the range of a water guide fracture zone of the low-level coal seam 1 and is parallel to the advancing direction of the low-level coal seam 4, the gas extraction roadway 15 is parallel to the return air cis-duct and the transportation cis-duct of the low-level coal seam 4, and when the low-level coal seam 4 is mined, gas generated in the low-level coal seam 4 and the high-level coal seam 1 is simultaneously extracted by the gas extraction roadway; if the gas extraction roadway 15 is positioned outside the caving zone of the high-level coal seam 1, the gas extraction roadway 15 can be used for continuously extracting gas when the high-level coal seam 1 is extracted in the later period; the arrangement mode of the gas extraction roadway can extract the gas of two coal beds (the residual gas of the low-level coal bed and the gas of the high-level coal bed) at one time, and the gas extraction roadway can be continuously used for extracting the residual gas of the high-level coal bed in the later period; the gas extracted in the step can be used for generating electricity or used as fuel gas after being treated; in this case, no matter which coal seam is mined first, the gas of the two layers of coal can be communicated, the gas of the two layers of coal seams needs to be treated simultaneously, if the high-level coal seam 1 is mined first, the goaf gas extraction is required to be carried out by adopting the scheme as illustrated in fig. 3, compared with the gas extraction roadway, the gas extraction roadway has better extraction effect, and the ventilation effect on the working face under mining is relatively small.
At this time, when the low-level coal seam 4 is located in the bottom plate transverse fracture zone 3 of the high-level coal seam 1, as shown in fig. 4, an air return gate 7 and a transportation gate 8 are arranged in the high-level coal seam 1, the air return gate 7 and the transportation gate 8 are connected through a coal face 9, a goaf 10 is formed after coal mining of the coal face, a gob-side entry retaining is carried out at the transportation gate 8 to form a transportation entry retaining way 12, a through-layer drilling 14 is constructed from the transportation entry retaining way 12 to the low-level coal seam 4, the through-layer drilling 14 penetrates through the bottom plate transverse fracture zone 3 to reach the low-level coal seam 4, a drainage screen pipe is arranged in the through-layer drilling 14, gas generated by pressure relief of the low-level coal seam 4 in the bottom plate transverse fracture zone 3 is drained through the drainage screen pipe, and the drained gas can be used for power generation or as gas after being processed; at the moment, the gas of the low-level coal seam is independent of the high-level coal seam, so that the communication of the gas in the high-level coal seam 1 and the gas in the low-level coal seam 4 can be reduced, the concentration of a gas accumulation part is reduced, and the possibility of gas dangerous accidents is reduced.
The high-level coal seam 1 is positioned in the water guide fracture zone of the low-level coal seam 4, which means that two layers of coal are relatively close to each other, and the situation that the low-level coal seam 4 is positioned in the bottom plate transverse fracture zone 3 of the high-level coal seam 1 is deep is almost impossible.
(5) If the high-level coal seam 1 is positioned in the water guiding fracture zone 6 of the low-level coal seam 4 to be high, namely the high-level coal seam 1 is positioned in the bending subsidence zone of the low-level coal seam 4;
at this time, when the low-level coal seam 4 is located in the bottom plate transverse fracture zone 3 of the high-level coal seam 1, as shown in fig. 4, an air return gate 7 and a transportation gate 8 are arranged in the high-level coal seam 1, the air return gate 7 and the transportation gate 8 are connected through a coal face 9, a goaf 10 is formed after coal mining of the coal face, a gob-side entry retaining is carried out at the transportation gate 8 to form a transportation entry retaining way 12, a through-layer drilling 14 is constructed from the transportation entry retaining way 12 to the low-level coal seam 4, the through-layer drilling 14 penetrates through the bottom plate transverse fracture zone 3 to reach the low-level coal seam 4, a drainage screen pipe is arranged in the through-layer drilling 14, gas generated by pressure relief of the low-level coal seam 4 in the bottom plate transverse fracture zone 3 is drained through the drainage screen pipe, and the drained gas can be used for power generation or as gas after being processed;
at this time, when the low-level coal seam 4 is positioned at the bottom plate transverse fracture zone 3 of the high-level coal seam 1 to be deep, as shown in fig. 6, the low-level coal seam 4 is mined first; specifically, the high-level coal seam 1 and rock formations near the top and bottom plates thereof are pre-fractured, so that the water guiding fracture zone 6 can develop to a certain position above the high-level coal seam 1 when the low-level coal seam 4 is mined, namely the water guiding fracture zone range of the low-level coal seam is artificially increased; constructing a gas extraction roadway 15 on the upper part of the high-level coal seam 1 and parallel to the advancing direction of the low-level coal seam 4, wherein the gas extraction roadway 15 is parallel to a return air cis-flute and a transportation cis-flute of the low-level coal seam 4, and when the low-level coal seam 4 is mined, gas generated in the low-level coal seam 4 and the high-level coal seam 1 is simultaneously extracted by utilizing the gas extraction roadway 15; the arrangement mode of the gas extraction roadway can extract the gas of two coal beds (residual gas of the low-level coal bed and gas of the high-level coal bed) at one time; the extracted gas can be used for generating electricity or used as fuel gas after being treated. If the high-level coal seam is located at a larger distance outside the range of the water guide fracture zone of the low-level coal seam, the two layers of coal seams are not called as the near-distance coal seam, the low-level coal seam can be mined firstly at this time, the pressure relief effect can still be generated on the upper-level coal seam by the exploitation of the low-level coal seam, the gas extraction can not be carried out on the high-level coal seam by adopting the gas treatment means, and the exploitation and the gas treatment can be independently carried out on the two layers of coal seams.
The high-level coal seam 1 is positioned in the water guide fracture zone of the low-level coal seam 4 to be high, which means that two layers of coal are far apart, and the situation that the low-level coal seam 4 is positioned in the bottom plate longitudinal guide passband 2 of the high-level coal seam 1 is impossible.
Under the above various working conditions, the gas extraction is required to be performed on the coal seam which is firstly extracted and then extracted, and the gas treatment method of the coal seam which is firstly extracted is not described in the foregoing, because the focus of the discussion is on how to plan the extraction sequence so that the coal seam which is currently extracted can generate better pressure relief and permeability improvement effects on the coal seam which is later extracted, the coal seam which is firstly extracted, namely the first extraction layer, adopts the prior art to perform gas pre-extraction and then extraction, and the gas pre-extraction means preferably adopts the method of constructing sequential drilling holes in the coal seam in the cis slots on the two sides of the working face of the coal seam which is firstly extracted.
The foregoing description is, of course, merely illustrative of preferred embodiments of the present invention, and it should be understood that the present invention is not limited to the above-described embodiments, but is intended to cover all modifications, equivalents and obvious modifications falling within the spirit and scope of the present invention as defined by the appended claims.
Claims (6)
1. The close-range coal seam mining gas control method based on the fracture characteristics of the roof and floor strata is characterized by comprising the following steps of:
(1) Determining the range of a bottom plate longitudinal guide passband and a bottom plate transverse fracture passband during high-level coal seam mining;
(2) Determining the range of a caving zone and a water guide fracture zone during low-level coal seam exploitation;
(3) If the high-level coal seam is positioned in the caving zone of the low-level coal seam;
3.1 When the low-level coal seam is positioned in the bottom plate longitudinal guide passband of the high-level coal seam, arranging a return air gate and a transportation gate in the high-level coal seam, connecting the return air gate and the transportation gate through a coal face, forming a goaf after coal mining by the coal face, forming a return air gate along a gob-side entry at the return air gate, and performing gas extraction on the goaf from the return air gate;
3.2 Or when the low-level coal seam is positioned in a transverse fracture zone of the bottom plate of the high-level coal seam, arranging a return air cis-slot and a transportation cis-slot in the high-level coal seam, connecting the return air cis-slot and the transportation cis-slot through a coal face, forming a goaf after coal mining by the coal face, forming a transportation drift along a gob-side entry retaining at the transportation cis-slot, and performing gas extraction from the transportation drift to a layer penetrating drill hole for low-level coal seam construction;
(4) If the high-level coal seam is positioned in the water guide fracture zone of the low-level coal seam;
4.1 When the low-level coal seam is positioned in the bottom plate longitudinal guide passband of the high-level coal seam, constructing a gas extraction roadway parallel to the advancing direction of the low-level coal seam in the range of the water guide fracture zone of the low-level coal seam at a certain position at the upper part of the high-level coal seam, and simultaneously extracting the gas generated in the low-level coal seam and the high-level coal seam by using the gas extraction roadway;
4.2 Or when the low-level coal seam is positioned in a transverse fracture zone of the bottom plate of the high-level coal seam, arranging a return air cis-slot and a transportation cis-slot in the high-level coal seam, connecting the return air cis-slot and the transportation cis-slot through a coal face, forming a goaf after coal mining by the coal face, forming a transportation drift along a gob-side entry retaining at the transportation cis-slot, and performing gas extraction from the transportation drift to a layer penetrating drill hole for low-level coal seam construction;
(5) If the high-level coal seam is positioned in the bending subsidence zone of the low-level coal seam;
5.1 When the low-level coal seam is positioned in a transverse fracture zone of a bottom plate of the high-level coal seam, arranging a return air cis-slot and a transportation cis-slot in the high-level coal seam, connecting the return air cis-slot and the transportation cis-slot through a coal face, forming a goaf after coal mining by the coal face, forming a transportation drift along a gob-side entry retaining at the transportation cis-slot, and performing gas extraction from the transportation drift retaining to a layer-penetrating drill hole in the low-level coal seam construction;
5.2 Or if the horizontal fracture zone of the bottom plate of the high-level coal bed is deep, pre-fracturing the high-level coal bed and the rock stratum near the top and bottom plates of the high-level coal bed, so that the water guiding fracture zone can develop to a certain position above the high-level coal bed when the low-level coal bed is mined; and constructing a gas extraction roadway on the upper part of the high-level coal seam in parallel to the advancing direction of the low-level coal seam, firstly mining the low-level coal seam, and simultaneously extracting the gas generated in the low-level coal seam and the high-level coal seam by using the gas extraction roadway.
2. The method for controlling gas in short distance coal seam mining according to claim 1, wherein in step 3.1), a bedding drill hole is constructed from a return air retaining roadway into a goaf, and a drainage screen pipe is arranged in the bedding drill hole to conduct gas drainage.
3. The method of claim 1, wherein in steps 3.2), 4.2) and 5.1), the through-bed borehole passes through the floor transverse fracture zone to reach the low seam, and a drainage screen is disposed in the through-bed borehole.
4. The method according to claim 1, wherein in step 4.1), the gas extraction roadway is located outside the caving zone of the high-level coal seam, and the gas extraction roadway is continuously used for extracting gas when the high-level coal seam is extracted.
5. A method of managing coal seam mining gas in close proximity according to any one of claims 1 to 4, wherein the extracted gas is treated for power generation or used as fuel gas.
6. A method of managing coal seam mining gas in close proximity according to any one of claims 1 to 4, wherein the coal seam is mined first by gas extraction and then by mining.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311765594.0A CN117803443A (en) | 2023-12-21 | 2023-12-21 | Close range coal seam mining gas control method based on roof-floor rock stratum breaking characteristics |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311765594.0A CN117803443A (en) | 2023-12-21 | 2023-12-21 | Close range coal seam mining gas control method based on roof-floor rock stratum breaking characteristics |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117803443A true CN117803443A (en) | 2024-04-02 |
Family
ID=90422644
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311765594.0A Pending CN117803443A (en) | 2023-12-21 | 2023-12-21 | Close range coal seam mining gas control method based on roof-floor rock stratum breaking characteristics |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117803443A (en) |
-
2023
- 2023-12-21 CN CN202311765594.0A patent/CN117803443A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107044289B (en) | A kind of bored grouting blocks the water damage control method of overlying strata water producing fractures main channel | |
| CN106907175B (en) | The efficient extraction coal roadway stripe gas of bottom plate concordant long drilled holes staged fracturing and region outburst elimination method | |
| CN107083988B (en) | Mining induced fissure band gas drainage technical method based on km directional drilling | |
| US6968893B2 (en) | Method and system for production of gas and water from a gas bearing strata during drilling and after drilling completion | |
| CN102080518B (en) | Method for extracting gas from coal seam roof complex branched well | |
| CN110242301A (en) | A kind of modified water-protection coal-mining method of two step slip casting of top plate water-bearing layer | |
| CN112593936B (en) | Advanced comprehensive control method for multi-disaster area of deep mine | |
| CN104314610A (en) | Coal road stripe region burst-preventing method | |
| US7493951B1 (en) | Under-balanced directional drilling system | |
| CN108343418B (en) | Method for controlling mining influence range from surface directional hydraulic fracturing pre-cracked bedrock | |
| CN112879011B (en) | Method for controlling height of water guide crack zone by hard overburden rock pre-cracking weakening under aquifer | |
| CN107120137B (en) | A kind of coal roadway tunneling is along seat earth Deephole pre-splitting blasting pumping method | |
| CN108894813B (en) | Gas outburst elimination method combining underground drilling, ground fracturing and underground extraction | |
| CN104963721A (en) | Downhole stereo rapid water drainage method through the combination of horizontal drilling holes and vertical drilling holes | |
| CN109611146B (en) | Separation layer water drainage grouting method | |
| US11976557B2 (en) | Coal bump control method for sectional hydraulic fracturing regions of near vertical ultra thick coal seam | |
| CN109736876B (en) | Large-diameter directional long-drill-hole extraction method for gas roof gushed by mining body | |
| CN115749776A (en) | Coal pillar recovery method based on fault grouting transformation | |
| CN114294046A (en) | Up-down three-dimensional extraction method for full-coverage well in coal mine area | |
| CN111677514B (en) | Roof weakening method | |
| CN103628914B (en) | The separate zone production of a kind of low-angle dip coal seam is visited to lower and is oozed the method for low-permeability thick-layer bedrock aquifer | |
| CN114278372B (en) | Diversion arrangement method for underground directional drilling area of huge thick water-rich layer | |
| CN111894672B (en) | Method for advanced treatment of roof separation water damage of stope by adopting ground drainage drilling | |
| CN117803443A (en) | Close range coal seam mining gas control method based on roof-floor rock stratum breaking characteristics | |
| CN109519210B (en) | A kind of single coal bed working face belly band detection and fixed point outburst elimination method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |