CN102562138A - Active decompression and outburst removal method for coal petrography dynamic disasters of expansion region of high gas-containing coal seam - Google Patents
Active decompression and outburst removal method for coal petrography dynamic disasters of expansion region of high gas-containing coal seam Download PDFInfo
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- CN102562138A CN102562138A CN2012100301743A CN201210030174A CN102562138A CN 102562138 A CN102562138 A CN 102562138A CN 2012100301743 A CN2012100301743 A CN 2012100301743A CN 201210030174 A CN201210030174 A CN 201210030174A CN 102562138 A CN102562138 A CN 102562138A
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Abstract
The invention discloses an active decompression and outburst removal method for coal petrography dynamic disasters of an expansion region of a high gas-containing coal seam. The active decompression and outburst removal method is characterized in that the position of a coal petrography dynamic disaster dangerous region is determined by means of monitoring expansion of the coal seam of a working surface, stress of the coal seam and gas pressure of the coal seam in real time, and the stress of the coal seam is effectively reduced and the expansion of the coal seam is eliminated so as to realize near-field decompression and active outburst removal of the coal petrography dynamic disasters of the expansion region of the coal seam of the working surface. The stress of the coal seam of the coal petrography dynamic disaster dangerous region is released effectively, concentrated stress affected by mining is sufficiently reduced, then expansion of the coal seam of the dynamic disaster dangerous region caused by mining of the working surface is avoided, the gas bearing state of the coal seam is improved and pressure of gas is reduced so as to eliminate potential safety hazards possibly causing the coal petrography dynamic disasters, and finally the purpose of active decompression and outburst removal of the coal petrography dynamic disasters of the expansion region of the high gas-containing coal seam is achieved. The active decompression and outburst removal method is simple in operation, high in pertinence and fine in active outburst removal effect to the coal petrography dynamic disasters of the working surface of the high gas-containing coal seam.
Description
Technical field
The present invention relates to a kind of high gas layer dilatation district coal rock dynamic disaster extinction method that initiatively reduces pressure, be used to realize the extinction of initiatively reducing pressure of dilatation district, high gas layer work plane coal seam coal rock dynamic disaster, prevent the generation of high gas layer work plane coal rock dynamic disaster.
Background technology
Coal rock dynamic disaster is the biggest threat of high gas layer work plane safety in production; In the generation of coal rock dynamic disaster and the work plane process of adopting in coal seam mechanical state and the coal seam gas occurrence status relevant; Heavily stressed, the high gas pressure district that dilatancy takes place in the coal seam is the hazardous area that is prone to take place coal rock dynamic disaster; Therefore, realize identification, and extinction technical measures reduction coal seam stress is implemented initiatively to reduce pressure to eliminate the coal seam dilatation in this zone the coal rock dynamic disaster hazardous area through real-time monitoring to coal seam dilatation, coal seam stress and coal-bed gas pressure; Can effectively prevent the generation of high gas layer work plane coal rock dynamic disaster, significant.The detection that does not also have at present to be directed against high gas layer work plane coal seam dilatancy specially reaches the recognition methods to coal rock dynamic disaster hazardous area, dilatation district; Therefore can't accurately judge position, high Gassy Coal Face coal rock dynamic disaster hazardous area; Also do not have through making the release of coal rock dynamic disaster hazardous area eliminate the coal seam dilatancy to realize the initiatively special measures of extinction; Cause the coal rock dynamic disaster preventing and controlling to lack specific aim, can't realize effective active extinction of high Gassy Coal Face coal rock dynamic disaster.
Summary of the invention
The inventive method is to prevent and treat in the method hazardous area and judge the deficiency inaccurate, that extinction measure specific aim is poor, the extinction effect is bad in order to overcome existing high gas layer work plane coal rock dynamic disaster, and coal rock dynamic disaster hazardous area, a kind of effectively detection of coal seam dilatation district, the extinction technical measures are with strong points, extinction the is effective high gas layer dilatation district coal rock dynamic disaster extinction method that initiatively reduces pressure is provided.
The inventive method is that the technical scheme that the technical solution problem is adopted is:
1, a kind of high gas layer dilatation district coal rock dynamic disaster extinction method that initiatively reduces pressure is characterized in that carrying out according to the following steps:
A, on crossheading under work plane the place ahead, help to construct respectively coal seam stress test boring and gas pressure testing bore holes; In boring of said coal seam stress test and gas pressure testing bore holes, coal seam measuring stress instrument and gas pressure tester are installed respectively, are formed coal seam stress measuring point and gas pressure measuring point respectively;
B, arrange that above the coal seam is surveyed a tunnel; The place ahead that in said detection tunnel, is arranged in working face wall is surveyed boring by the base plate of surveying the tunnel to coal seam construction dilatation, in said dilatation detection boring, coal body dilatation probe is installed and is formed coal body dilatation measuring point; Said coal body dilatation measuring point is consistent with the horizontal range of coal seam stress measuring point and gas pressure measuring point and work plane;
C, along with the propelling of work plane; In real time coal body dilatation probe, coal seam measuring stress instrument and coal-bed gas pressure tester are advanced monitoring; When coal body dilatation amount, coal seam stress and gas pressure surpass margin of safety simultaneously, confirm that the zone by coal seam stress measuring point, gas pressure measuring point and coal body dilatation measuring point place section to work plane is the coal rock dynamic disaster hazardous area;
D, to the coal rock dynamic disaster hazardous area of confirming; Work plane perpendicular to rib in the coal body in said coal rock dynamic disaster hazardous area, construct be parallel to each other respectively move towards destressing borehole; Utilization is moved towards destressing borehole coal-bed flooding is implemented in said coal rock dynamic disaster hazardous area, makes the softening release of coal body in coal rock dynamic disaster hazardous area;
E, crossheading is parallel to each other to the coal body construction in said coal rock dynamic disaster hazardous area perpendicular to coal group under work plane each along layer destressing borehole, make coal rock dynamic disaster hazardous area coal mass relief.
2, the high gas layer dilatation according to claim 1 district coal rock dynamic disaster extinction method that initiatively reduces pressure, it is characterized in that: the aperture of said gas pressure testing bore holes is 70mm, hole depth is 30m; The aperture of said coal seam stress test boring is 45mm, and hole depth is 10m.
3, the high gas layer dilatation according to claim 1 district coal rock dynamic disaster extinction method that initiatively reduces pressure; It is characterized in that: the said destressing borehole that moves towards runs through said coal rock dynamic disaster hazardous area; The aperture of moving towards destressing borehole is 150mm, and adjacent pitch of holes is 5m.
4, the high gas layer dilatation according to claim 1 district coal rock dynamic disaster extinction method that initiatively reduces pressure, it is characterized in that: said aperture along layer destressing borehole is 150mm, and hole depth is 120m, and the adjacent holes spacing is 5m.
Compared with present technology, beneficial effect of the present invention is embodied in:
The inventive method is through the enforcement monitoring to coal seam stress, coal-bed gas pressure and coal seam dilatancy; Can effectively differentiate high gas layer dilatation district to confirm the position in coal rock dynamic disaster hazardous area; And this regional coal-seam implemented destressing borehole and coal-bed flooding technical measures targetedly; Can significantly reduce coal rock dynamic disaster hazardous area stress in coal bed, eliminate the coal seam dilatancy that possibly cause coal rock dynamic disaster; And improve the gas bearing state, finally reach initiatively the reduce pressure purpose of extinction of high gas layer work plane coal rock dynamic disaster; The inventive method construction is simple, with strong points, extinction is effective, can realize effectively preventing the generation of dilatation district, high gas layer work plane coal seam coal rock dynamic disaster.
Description of drawings
Fig. 1 is the floor map of coal seam stress in the inventive method, gas pressure, coal seam dilatation test;
Fig. 2 is work plane destressing borehole and a coal-bed flooding generalized section in the inventive method;
Fig. 3 is a following crossheading destressing borehole generalized section in the inventive method;
Fig. 4 a is the structural representation of applied coal body dilatation probe in the inventive method;
Fig. 4 b is an applied coal body dilatation survey meter end view in the inventive method;
Fig. 5 is a coal body dilatation probe mounting means sketch map in the inventive method.
Label among the figure: 21 detection tunnels; 22 coal seams; Boring is surveyed in 23 dilatations; 31 along layer destressing borehole; 32 times crossheadings; 33 gas pressure testing bore holes; 34 coal seam stress test borings; 35 move towards destressing borehole; 36 work planes; 37 goafs; 38 coal rock dynamic disaster hazardous areas; 11 large diameter steel pipes; 12 minor-diameter steel-tubes; 3a large-diameter pipe steel shell fragment; 3b small diameter tube steel shell fragment; 14 graduation marks.
The specific embodiment
The coal rock dynamic disaster extinction method that initiatively reduces pressure in high gas layer dilatation district is to carry out according to the following steps in the present embodiment:
1, referring to Fig. 1; Group construct respectively boring 34 of coal seam stress test and gas pressure testing bore holes 33 on crossheading 32 under work plane 36 the place aheads; In boring 34 of coal seam stress test and gas pressure testing bore holes 33, coal seam measuring stress instrument and gas pressure tester are installed respectively, are formed coal seam stress measuring point and gas pressure measuring point respectively with this; In order to guarantee enough observed ranges, the place ahead that coal seam stress measuring point and gas pressure measuring point should be in work plane 36 is not less than the position of 60m.
2, referring to Fig. 1 and Fig. 5; Above coal seam 22, be not less than the 15m position and arrange that is surveyed a tunnel 21; The place ahead that in surveying tunnel 21, is arranged in working face wall by the base plate of surveying tunnel 21 to the coal seam 22 construction dilatations survey boring 23, survey in dilatation and coal body dilatation probe is installed in the boring 23 is formed coal body dilatation measuring point; In the practical implementation, the horizontal range of coal body dilatation measuring point to work plane 36 should be consistent with the horizontal range of coal seam stress measuring point and gas pressure measuring point to work plane 36.
3, along with the propelling of work plane 36; In real time coal body dilatation probe, coal seam measuring stress instrument and coal-bed gas pressure tester are advanced monitoring; When coal body dilatation amount, coal seam stress and gas pressure surpass margin of safety simultaneously, confirm that the zone by coal seam stress measuring point, gas pressure measuring point and coal body dilatation measuring point place section to work plane 36 is coal rock dynamic disaster hazardous area 38; In the practical implementation, margin of safety generally is set at: coal body dilatation cubical expansivity is 1.5%, coal seam stress is initial stress, and 1.6 times, coal-bed gas pressure are 0.7MPa.
4, to the coal rock dynamic disaster hazardous area of confirming 38; Work plane 36 perpendicular to rib in the coal body in coal rock dynamic disaster hazardous area 38, construct be parallel to each other respectively move towards destressing borehole 35; Utilization is moved towards 35 pairs of coal rock dynamic disaster hazardous areas of destressing borehole 38 and is implemented coal-bed flooding, makes the softening release (as shown in Figure 2) of coal body in coal rock dynamic disaster hazardous area 38.
5, crossheading 32 makes coal rock dynamic disaster hazardous area 38 coal mass relief (as shown in Figure 3) perpendicular to each suitable layer destressing borehole 31 that coal group constructs and is parallel to each other to the coal body in coal rock dynamic disaster hazardous area 38 under work plane.
In the practical implementation, the aperture of gas pressure testing bore holes 33 is 70mm, and hole depth is 30m; The aperture of coal seam stress test boring 34 is 45mm, and hole depth is 10m; The aperture of moving towards destressing borehole 35 is 150mm, and adjacent pitch of holes is 5m.Aperture along layer destressing borehole 31 is 150mm, and hole depth is 120m, and the adjacent holes spacing is 5m.
In the present embodiment; Coal body dilatation survey meter adopts the form of structure shown in Fig. 4 a and Fig. 4 b; The employing tube-in-tube structure is provided with large diameter steel pipe 11 and is applied in the minor-diameter steel-tube 12 in the large diameter steel pipe 11, and minor-diameter steel-tube 12 can axially move in large diameter steel pipe 11; Be umbrella at the front end of large diameter steel pipe 11 and be provided with each large-diameter pipe steel shell fragment 3a, be umbrella at the front end of minor-diameter steel-tube 12 and be provided with each small diameter tube steel shell fragment 3b; Be evenly to distribute in steel pipe front end periphery with four steel shell fragments in the present embodiment, rise each steel shell fragment in boring of support is that form with ratchet makes large diameter steel pipe 11 and minor-diameter steel-tube 12 be separately fixed on the relevant position not displacement backward; Be provided for measuring the graduation mark 14 of the axial relative shift between large diameter steel pipe 11 and the minor-diameter steel-tube 12 vertically at the afterbody of minor-diameter steel-tube 12.
In the practical implementation, the diameter that large diameter steel pipe 11 can be set is 40mm, and each large-diameter pipe steel shell fragment 3a is after opening, and the diameter of the disk that its each steel shell fragment front end is is 60mm; The diameter of minor-diameter steel-tube 12 is 35mm, and each small diameter tube steel shell fragment 3b is after opening, and the diameter of its each steel shell fragment disk that front end is is 55mm; The scale division value that minor-diameter steel-tube 12 afterbody graduation marks 14 are set is 1mm, and range is not less than 500mm.
The mounting means of coal body dilatation probe is as shown in Figure 5; Coal body dilatation probe is placed in the detection boring 23; The bottom, hole that the pipe front end of minor-diameter steel-tube 12 is reached survey boring 23, and make the pipe front end of pipe front end and the minor-diameter steel-tube 12 of large diameter steel pipe 11 be no less than the distance of 1.5m apart; The afterbody scale value L1 of record coal body dilatation this moment probe; When dilatancy that coal body generation volume increases, minor-diameter steel-tube 12 is subjected to displacement to the deep that boring 23 is surveyed in dilatation with respect to large diameter steel pipe 11, and displacement is read by graduation mark 14, judges with this whether coal body dilatation takes place.
In the present embodiment, it is the gas gauge of 0-1.6MPa that the gas pressure tester adopts range, and the piezometer tube of in testing bore holes, packing into during test is installed gas gauge in the pipe outer end behind the injection hole sealing, with advance of the face observation and record gas pressure meter reading; The coal seam measuring stress instrument adopts KS II-1 type borehole stressmeter, and borehole stressmeter is installed in testing bore holes during test, with advance of the face observation and record borehole stressmeter reading.
In the practical implementation, survey the position of tunnel 21 above the work plane coal seam,, can suitably adjust according to concrete field condition to be principle away from the coal seam as far as possible.Gas pressure testing bore holes 33 and the distance of stress test boring 34 in coal seam with work plane are principle to guarantee enough observed ranges, can suitably adjust according to concrete field condition.
Claims (4)
1. high gas layer dilatation district coal rock dynamic disaster extinction method that initiatively reduces pressure is characterized in that carrying out according to the following steps:
A, crossheading (32) attendes group construct the respectively boring of coal seam stress test (34) and gas pressure testing bore holes (33) under work plane (36) the place ahead; In said coal seam stress test boring (34) and gas pressure testing bore holes (33), coal seam measuring stress instrument and gas pressure tester are installed respectively, are formed coal seam stress measuring point and gas pressure measuring point respectively;
B, the top of (22) arranges that is surveyed a tunnel (21) in the coal seam; The place ahead that in said detection tunnel (21), is arranged in working face wall is surveyed boring (23) by the base plate of surveying tunnel (21) to coal seam (22) construction dilatation, coal body dilatation probe is installed in said dilatation detection boring (23) is formed coal body dilatation measuring point; Said coal body dilatation measuring point is consistent with the horizontal range of coal seam stress measuring point and gas pressure measuring point and work plane (36);
C, along with the propelling of work plane (36); In real time coal body dilatation probe, coal seam measuring stress instrument and coal-bed gas pressure tester are advanced monitoring; When coal body dilatation amount, coal seam stress and gas pressure surpass margin of safety simultaneously, confirm that the zone by coal seam stress measuring point, gas pressure measuring point and coal body dilatation measuring point place section to work plane (36) is coal rock dynamic disaster hazardous area (38);
D, to the coal rock dynamic disaster hazardous area of confirming (38); Work plane (36) perpendicular to rib in the coal body in said coal rock dynamic disaster hazardous area (38), construct be parallel to each other respectively move towards destressing borehole (35); Utilization is moved towards destressing borehole (35) coal-bed flooding is implemented in said coal rock dynamic disaster hazardous area (38), makes the softening release of coal body in coal rock dynamic disaster hazardous area (38);
E, crossheading (32) is parallel to each other to the coal body construction in said coal rock dynamic disaster hazardous area (38) perpendicular to coal group under work plane each along layer destressing borehole (31), make coal rock dynamic disaster hazardous area (38) coal mass relief.
2. the high gas layer dilatation according to claim 1 district coal rock dynamic disaster extinction method that initiatively reduces pressure, it is characterized in that: the aperture of said gas pressure testing bore holes (33) is 70mm, hole depth is 30m; The aperture of said coal seam stress test boring (34) is 45mm, and hole depth is 10m.
3. the high gas layer dilatation according to claim 1 district coal rock dynamic disaster extinction method that initiatively reduces pressure; It is characterized in that: the said destressing borehole (35) that moves towards runs through said coal rock dynamic disaster hazardous area (38); The aperture of moving towards destressing borehole (35) is 150mm, and adjacent pitch of holes is 5m.
4. the coal rock dynamic disaster extinction method that initiatively reduces pressure in high gas layer dilatation according to claim 1 district is characterized in that: a said aperture along layer destressing borehole (31) is 150mm, and hole depth is 120m, and the adjacent holes spacing is 5m.
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| CN201210030174.3A CN102562138B (en) | 2012-02-10 | 2012-02-10 | Active decompression and outburst removal method for coal petrography dynamic disasters of expansion region of high gas-containing coal seam |
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| CN201210030174.3A CN102562138B (en) | 2012-02-10 | 2012-02-10 | Active decompression and outburst removal method for coal petrography dynamic disasters of expansion region of high gas-containing coal seam |
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| CN108223010A (en) * | 2017-12-29 | 2018-06-29 | 黑龙江科技大学 | Dynamic mine disaster integral early warning method and device |
| CN112343647A (en) * | 2020-10-22 | 2021-02-09 | 煤炭科学技术研究院有限公司 | Method for preventing and controlling self-discharging pressure-eliminating outburst-eliminating rapid tunneling gas of adjacent air tunnel |
| CN114961696A (en) * | 2022-05-31 | 2022-08-30 | 西安科技大学 | Method for detecting gas parameters in directional long drill hole of coal seam |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108223010A (en) * | 2017-12-29 | 2018-06-29 | 黑龙江科技大学 | Dynamic mine disaster integral early warning method and device |
| CN112343647A (en) * | 2020-10-22 | 2021-02-09 | 煤炭科学技术研究院有限公司 | Method for preventing and controlling self-discharging pressure-eliminating outburst-eliminating rapid tunneling gas of adjacent air tunnel |
| CN114961696A (en) * | 2022-05-31 | 2022-08-30 | 西安科技大学 | Method for detecting gas parameters in directional long drill hole of coal seam |
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