CN113446051B - Goaf ultrahigh-position drill hole gas extraction method under roof cutting and entry retaining process - Google Patents
Goaf ultrahigh-position drill hole gas extraction method under roof cutting and entry retaining process Download PDFInfo
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- CN113446051B CN113446051B CN202110872921.7A CN202110872921A CN113446051B CN 113446051 B CN113446051 B CN 113446051B CN 202110872921 A CN202110872921 A CN 202110872921A CN 113446051 B CN113446051 B CN 113446051B
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- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000000605 extraction Methods 0.000 title claims abstract description 10
- 239000004047 hole gas Substances 0.000 title description 3
- 238000005553 drilling Methods 0.000 claims abstract description 45
- 238000009423 ventilation Methods 0.000 claims abstract description 16
- 238000010276 construction Methods 0.000 claims abstract description 10
- 239000000463 material Substances 0.000 claims abstract description 3
- 229920002635 polyurethane Polymers 0.000 claims abstract description 3
- 239000004814 polyurethane Substances 0.000 claims abstract description 3
- 238000005065 mining Methods 0.000 claims description 16
- 239000003245 coal Substances 0.000 claims description 8
- 230000000149 penetrating effect Effects 0.000 claims description 3
- 230000035515 penetration Effects 0.000 claims description 2
- 230000000903 blocking effect Effects 0.000 abstract description 3
- 230000001502 supplementing effect Effects 0.000 description 2
- 238000005516 engineering process 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
- 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
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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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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
- E21D9/14—Layout of tunnels or galleries; Constructional features of tunnels or galleries, not otherwise provided for, e.g. portals, day-light attenuation at tunnel openings
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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
- E21F1/00—Ventilation of mines or tunnels; Distribution of ventilating currents
- E21F1/006—Ventilation at the working face of galleries or tunnels
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- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
Abstract
The invention belongs to the technical field of gas extraction, and particularly relates to a goaf ultrahigh-position drilling gas extraction method under a roof cutting and roadway retaining process. Comprises the following steps. S100, under the roof cutting and entry retaining process, a supplementary entry is formed on one side of a goaf of a stope face, the supplementary entry is communicated with a return airway of an adjacent face to form a new air inlet entry, and the ventilation mode of the face is changed from U-shaped ventilation to Y-shaped ventilation. S200, arranging a drill site I at the position of the cut hole adjacent to the working face, and arranging a drill site II at the outer side of the air inlet lane at one side of the lane patching. S300, constructing ultrahigh directional long drill holes in the drill site I and the drill site II by using a kilometer directional drilling machine. S400, after the drilling construction is completed, embedding an end pipe made of the polyurethane material in advance, and then installing a gas drainage pipe in the end pipe to pre-drain gas. The blocking and blocking of the drill hole caused by the collapse of the top plate in the working face stoping process can be effectively reduced, so that the gas in the goaf can be continuously extracted, the gas concentration in the goaf is reduced, and the gas escape in the goaf is reduced.
Description
Technical Field
The invention belongs to the technical field of gas extraction, and particularly relates to a goaf ultrahigh-position drilling gas extraction method under a roof cutting and roadway retaining process.
Background
Under the roof cutting and entry retaining process, one side of a goaf forms an entry-supplementing mode, the original U-shaped ventilation mode of a stope face is changed into a Y-shaped ventilation mode, and although the caving roadway side is subjected to guniting treatment to isolate the goaf, the air leakage phenomenon still exists, gas can overflow the entry-supplementing mode, so that the concentration of the gas in the entry-supplementing mode is over-limited, and great potential safety hazards are brought. Therefore, the problem of over-limit of the concentration of the gas in the roadway repairing is solved, and the important link of mine gas control is formed. And the drilling holes of the traditional high-position drilling process can be blocked or blocked along with the collapse of the top plate of the goaf, so that part of gas still enters the roadway repairing, the concentration of the gas in the roadway repairing is increased, and finally the concentration of the gas in the roadway repairing is over-limit.
Disclosure of Invention
The invention provides a goaf ultrahigh-position drilling gas extraction method under a roof-cutting and roadway-retaining process, aiming at solving the problems that continuous extraction cannot be carried out and roadway-supplementing gas concentration is over-limited in goaf extracted gas.
The invention adopts the following technical scheme: a goaf ultrahigh-position drill hole gas extraction method under a roof-cutting roadway-retaining process comprises the following steps.
S100, under the roof cutting and entry retaining process, a supplementary entry is formed on one side of a goaf of a stope face, the supplementary entry is communicated with a return airway of an adjacent face to form a new air inlet entry, and the ventilation mode of the face is changed from U-shaped ventilation to Y-shaped ventilation.
S200, arranging a drill site I at the hole cutting position of the adjacent working surface, and arranging a drill site II at the outer side of the air inlet roadway on one side of the roadway repairing.
S300, constructing ultrahigh directional long drill holes in the drill site I and the drill site II by using a kilometer directional drilling machine.
S400, after the drilling construction is completed, embedding an end pipe made of the polyurethane material in advance, and then installing a gas drainage pipe in the end pipe to pre-drain gas.
Furthermore, the distance between the drilling site I and the working face air inlet roadway is 50-100 m, and the height of the drilling site is 2-15 m above the top of the coal seam.
Furthermore, the distance between the drilling sites II is 150-200 m, and the height of the drilling sites is 2-15 m above the top of the coal seam.
Further, in the step S300, hole distribution is performed in the drill site in a 'drilling fan-shaped and final hole parallel mode', a drilling process that 'after hole opening, layer penetration is performed to a target mining height position firstly, then directional construction is performed to a designed hole depth along the target mining height position according to a target azimuth angle and a coal seam inclination angle' is performed in the construction process, a drill hole of the drill site II is constructed in a top plate, a drill hole is formed in an inclined upward direction along a vertical surface of a roadway to the target mining height position, then the drill hole penetrates through the vertical surface of the roadway to be driven into the goaf, during the drill hole construction of the drill site I in the cutting hole, the drill hole reaches the target mining height position on the outer side of a vertical surface of a roadway supplementing position firstly, then penetrates through the vertical surface of the roadway supplementing to be driven into the goaf, and the final hole position of the drill hole is designed to be more than 15 times of the mining height.
Compared with the prior art, the drill sites are respectively constructed in the roadway repairing and the cutting holes, meanwhile, an ultrahigh drilling mode is adopted in the drill sites, compared with the traditional high drilling method, the drilling holes are constructed from the outer side of the roadway and are deeper in drilling depth, and blocking and blockage caused by roof collapse in the working face stoping process can be effectively reduced, so that gas in the goaf can be continuously extracted, the gas concentration in the goaf is reduced, gas escape in the goaf is reduced, and the problem of gas concentration overrun in the roadway repairing is solved.
Drawings
FIG. 1 is a schematic view of an ultra-high position drilling plan layout;
FIG. 2 is a schematic view of a cross-sectional layout of an ultra-high position borehole;
FIG. 3 is a cross-sectional view of a drill hole of drill site I
FIG. 4 is a schematic cross-sectional view of a drill site II
FIG. 5 is a schematic view of 4502 face super elevation drilling in the example;
FIG. 6 is a schematic view of the U-shaped ventilation in the embodiment;
FIG. 7 is a schematic view of the Y-shaped ventilation in the embodiment;
in the figure, 1-stope working face, 2-adjacent working face, 3-mend lane, 4-return lane, 5-air inlet lane, 6-cut hole, 7-drill site I, 8-drill site II, 9-goaf.
Detailed Description
The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings.
Example (b):
4502 the working face adopts a roof cutting and entry retaining process, so that the ventilation mode is changed from U-shaped ventilation to Y-shaped ventilation, and although the caving roadway sides are subjected to guniting treatment to isolate a goaf, air leakage still exists, gas can overflow to the entry patching, so that the concentration of the gas in the entry patching is over-limit, and therefore the gas in the goaf on one side of the entry patching needs to be extracted by adopting an ultra-high drilling method.
The method comprises the steps of arranging 1 drill site at the outer side of a position 50m away from a 4502 working face of a cutting distance of a 4503 working face, arranging ultrahigh-position directional long drill holes on the drill site, arranging the holes in a mode of hole opening fan-shaped and end hole parallel, constructing by adopting a drilling process of firstly penetrating a layer to a target mining height layer after hole opening and then directionally constructing to a designed hole depth along the target mining height layer according to a target azimuth angle and a coal seam inclination angle, arranging 3 drill holes on the drill site, wherein the average depth is 468m, and the diameter of the final hole of each drill hole is 105 mm. The hole opening distance of each group of adjacent drill holes is 1m, and the final hole distance is 5 m. And the 1#, 2#, and 3# drilling terminal hole ends are controlled at the position 17 times the mining height above the top plate.
3 drilling fields are arranged on the north side wall at 700m, 500m and 300m positions of the upper air inlet lane and the tangent hole horizontal distance of the 4502 working surface, ultrahigh-position directional long drill holes are arranged in the drilling fields in a combined mode along the upper air inlet lane inclination of the 4502 working surface, the holes are distributed in a mode of opening a fan shape and parallel final holes, a drilling process that the holes are drilled firstly, penetrate through the layer to a target mining height position and then are directionally constructed to the designed hole depth along the target mining height position according to a target azimuth angle and a coal seam inclination angle is adopted in construction, 3 drill holes are arranged on each drilling field, the average drilling depth is 279m, and the diameter of the final drilled hole is 105 mm. The hole opening distance of each group of adjacent drill holes is 1m, and the final hole distance is 5 m. The drilling terminal hole end is controlled at the position 16 times the mining height above the top plate.
By adopting the goaf ultrahigh-position drilling technology under the roof-cutting and roadway-retaining process, the safety problem that the 4502 working face roadway-repairing gas concentration exceeds the limit can be effectively solved.
Claims (3)
1. A goaf ultrahigh-position drilling gas extraction method under a roof-cutting and roadway-retaining process is characterized by comprising the following steps: comprises the following steps of (a) preparing a solution,
s100, under the roof cutting and entry retaining process, a supplementary tunnel (3) is formed on one side of a goaf (9) of a stope face (1), the supplementary tunnel (3) is communicated with a return airway (4) of an adjacent face (2) to form a new air inlet tunnel, and the ventilation mode of the stope face is changed from U-shaped ventilation to Y-shaped ventilation;
s200, arranging a drill site I (7) at the position of the cut hole (6) of the adjacent working face (2), and arranging a drill site II (8) in the air inlet lane (5) on one side of the roadway patching (3);
s300, constructing ultrahigh directional long drill holes in a drill site I (7) and a drill site II (8) by using a kilometer directional drilling machine; in the step S300, hole distribution is carried out in a drilling field in a mode of hole opening sector and end hole parallel, a drilling process that hole opening is carried out, layer penetration is carried out firstly to a target mining height position, then directional construction is carried out along the target mining height position to designed hole depth according to a target azimuth angle and a coal seam inclination angle is adopted in construction, drilling holes of a drilling field II (8) are constructed in a top plate, the drilling holes are obliquely upwards drilled to the target mining height position along a vertical surface of a roadway and then are driven into a goaf by penetrating through the vertical surface of the roadway, during drilling construction of a drilling field I (7) in a cutting hole, drilling holes reach the target mining height position on the outer side of a vertical surface of a supplementary roadway (3) and then are driven into the goaf (9) by penetrating through the vertical surface of the supplementary roadway (3), and the position of end holes of the drilling holes is designed to be more than 15 times of the mining height;
S400, after the drilling construction is finished, embedding an end pipe made of the polyurethane material in advance, and then installing a gas drainage pipe in the end pipe to pre-drain gas.
2. The method for extracting gas from the ultrahigh-position drilled hole of the goaf in the roof-cutting roadway-retaining process according to claim 1, wherein the method comprises the following steps: the distance between the drill site I (7) and the working face air inlet roadway is 50-100 m, and the height of the drill site is 2-15 m above the top of the coal seam.
3. The method for extracting gas from the ultrahigh-position drilled hole of the goaf in the roof-cutting roadway-retaining process according to claim 1, wherein the method comprises the following steps: the distance between the drilling sites II (8) is 150-200 m, and the height of the drilling sites is 2-15 m above the top of the coal seam.
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| CN202110872921.7A CN113446051B (en) | 2021-07-30 | 2021-07-30 | Goaf ultrahigh-position drill hole gas extraction method under roof cutting and entry retaining process |
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