CN104234739A - In-borehole gas explosion coal body cracking forced extraction method - Google Patents
In-borehole gas explosion coal body cracking forced extraction method Download PDFInfo
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Abstract
The invention discloses an in-borehole gas explosion coal body cracking forced extraction method, and is applied to the efficient extraction of underground gas of a coal mine. An air pump is used for pressing air into a sealed borehole, the air and gas gushed from the borehole are premixed to form mixed gas at concentration of 9 to 10 percent, and the mixed gas is detonated by virtue of an ignition device to form explosion waves to crack a coal body to construct a fracture network; meanwhile, by thermal effects achieved by explosion, the adsorption potential of the gas can be remarkably lowered, and the desorption and the flowing of the gas can be promoted, so that the aim of forced gas extraction of a high-gas low-air-permeability coal seam is fulfilled. The method is low in cost, simple, easy, time-saving and labor-saving; the effective pressure relief influence scope of a single hole can be remarkably widened, and the gas extraction efficiency of the coal seam can be improved by over 40 percent.
Description
Technical field
The present invention relates to a kind of gas blastingfracture coal body enhanced gas extraction method in boring, be particularly useful for the efficient extraction of gas of underground coal mine high gassy and low permeability coal seam.
Background technology
The fundamental means that China's coal-mine fire damp is administered is the gas pumping measure based on drilling gas extraction way.Along with China's coal-mine enters deep mining, the low Dominated Factors becoming the efficient extraction of restriction gas gradually of gas permeability of coal seam.Therefore, strengthen anti-reflection becoming and improve gas pumping effect, realize the key technology of deep coal and gas power phenomenon.Blasting shock wave damage coal body enhanced gas extraction method is one of effective measures that facts have proved in recent years.It mainly leans against inside, coal seam and installs explosive, and the shock wave utilizing blast to produce carries out damage to coal body, produces crack, thus increases gas permeability of coal seam, improves gas pumping effect.But this method exists powder charge difficulty or powder charge blind area, restriction is on-the-spot applies or occurs the phenomenon that release is uneven.Explosive is dangerous matter sources inherently, produces also there is certain threat for downhole safety.Therefore, it is very necessary for finding the anti-reflection measure of a kind of strengthening time saving and energy saving, simple and with low cost, and this is to raising mine gas extraction efficiency and prevent coal and gas prominent significant.
Essentially, gas explosion is the vigorous oxidation reaction that certain density methane and air occur.When gas density lower than 5% time, meet fire do not explode, but can flame periphery formed burning zone, when gas density is 9.5%, its brisance maximum (oxygen and gas complete reaction); When gas density is more than 16%, lose its explosivity, but chance fire still can burn in atmosphere.The HTHP that gas explosion produces, impels the gas near quick-fried source outwards to impact with great speed, causes casualties, and destroys tunnel and equipment facility, and a large amount of coal dust make it to participate in blast kicked up, produces larger destructive power.In addition, generate a large amount of pernicious gases after blast, the personnel that cause are poisoned to death.For a long time, gas explosion brings huge threat to the safety in production in colliery.But, when gas explosion realizes controlled, and by the impact force fracturing coal body of gas explosion, build Fracture Networks; Meanwhile, the fuel factor that gas explosion produces reduces gas adsorption potential energy, promotes desorption of mash gas flowing, has a very important role to raising drilling gas extracting result.
Summary of the invention
Technical problem: the object of the invention is the weak point overcome in prior art, provides the anti-reflection measure of strengthening time saving and energy saving, simple and with low cost.
Technical scheme: gas blastingfracture coal body enhanced gas extraction method in one boring of the present invention, comprising: the 1) position, hole of interlaced arrangement drainage holes and explosive hole in coal seam; 2) construct drainage holes, sealing of hole, link gas pumping pipe network and carry out gas pumping; 3) creep into through roof 1m place at position, the hole place of explosive hole with rig, move back brill; Also comprise the steps:
A. by the conducting wire binding of igniter on detector tube, then detector tube is sent at the bottom of explosive hole, makes the wire front end of colligation on detector tube be positioned in the middle part of coal seam;
B. Grouting Pipe, return pipe and air injection pipe are sent in explosive hole, block aperture;
C. open grouting pump, slip casting in explosive hole, when return pipe overfall, stop slip casting;
D., after grout cures, open air pump, in explosive hole, be pressed into air by air injection pipe;
E. open the valve on detector tube, detect the gas density in explosive hole by portable watt of inspection instrument, when gas density reaches 9 ~ 10%, close air pump and valve;
F. starting ignition device, ignites the gas in explosive hole, the coal body around fracturing explosive hole, makes to produce a large amount of cracks in coal body, runs through the drainage holes around explosive hole;
G. open valve, detector tube is incorporated to gas pumping pipe network and carries out gas pumping, complete the operation of an explosive hole.
The pipeline section that described detector tube is positioned at coal seam section is evenly distributed with some apertures; Described air injection pipe is than overfall pipe range 0.5m.
Beneficial effect: owing to have employed technique scheme, air pump is utilized to be pressed into air in the boring of sealing, air and the gas premix gushed out in boring formed concentration 9% ~ 10% high pressure gas mist, mist is ignited by igniter, form explosion wave, fracturing coal body, builds Fracture Networks; The fuel factor produced of simultaneously exploding can significantly reduce gas adsorption gesture, promotes desorption of mash gas and flowing, thus reaches the object of high gassy and low permeability coal seam strengthening gas pumping.The method is with low cost, simple, time saving and energy saving, is not only suitable for perform hole, also has good applicability to lower perform hole and lateral aperture simultaneously, significantly can expand the effective unload effects scope of single hole, makes coal bed gas extraction efficiency improve more than 40%.
Accompanying drawing explanation
Fig. 1 is gas blastingfracture coal body enhanced gas extraction method schematic diagram in boring of the present invention;
In figure: 1-grouting pump, 2-air pump, 3-igniter, 4-Grouting Pipe, 5-return pipe, 6-detector tube, 7-valve, 8-air injection pipe.
Detailed description of the invention
Below in conjunction with accompanying drawing, one embodiment of the present of invention are further described:
As shown in Figure 1, gas blastingfracture coal body enhanced gas extraction method in boring of the present invention, concrete steps are as follows:
A. the position, hole of interlaced arrangement drainage holes and explosive hole in coal seam according to a conventional method;
B. construct drainage holes, sealing of hole, link gas pumping pipe network and carry out gas pumping;
C. creep into through roof 1m place at position, the hole place of explosive hole with rig, move back brill;
D. by the conducting wire binding of igniter 3 on detector tube 6, then detector tube 6 is sent at the bottom of explosive hole, makes the wire front end of colligation on detector tube 6 be positioned in the middle part of coal seam; The pipeline section that detector tube 6 is positioned at coal seam section is evenly distributed with some apertures; Wherein igniter adopts EPD series portable high-energy electric ignition device;
E. Grouting Pipe 4, return pipe 5 and air injection pipe 8 are sent in explosive hole, block aperture; Wherein, air injection pipe 8 0.5m longer than return pipe 5;
F. open grouting pump 1, slip casting in explosive hole, when return pipe 5 overfall, stop slip casting;
G., after grout cures, open air pump 2, in explosive hole, be pressed into air by air injection pipe 8;
H. open the valve 7 on detector tube 6, detect the gas density in explosive hole by portable watt of inspection instrument, when gas density reaches 9 ~ 10%, close air pump 2 and valve 7;
I. starting ignition device 3, ignites the gas in explosive hole, the coal body around fracturing explosive hole, makes to produce a large amount of cracks in coal body, runs through the drainage holes around explosive hole;
J. open valve 7, detector tube 6 is incorporated to gas pumping pipe network and carries out gas pumping, complete the operation of an explosive hole, repeat above-mentioned steps, complete the operation of next explosive hole.
The present invention also can to the extraction carrying out the strengthening of gas explosion fracturing coal body in lateral aperture and descending boring.
Claims (3)
1. a gas blastingfracture coal body enhanced gas extraction method in boring, comprising: the 1) position, hole of interlaced arrangement drainage holes and explosive hole in coal seam; 2) construct drainage holes, sealing of hole, link gas pumping pipe network and carry out gas pumping; 3) creep into through roof 1m place at position, the hole place of explosive hole with rig, move back brill; It is characterized in that, also comprise the steps:
A. by the conducting wire binding of igniter (3) on detector tube (6), then detector tube (6) is sent at the bottom of explosive hole, makes the wire front end of colligation on detector tube (6) be positioned in the middle part of coal seam;
B. Grouting Pipe (4), return pipe (5) and air injection pipe (8) are sent in explosive hole, block aperture;
C. open grouting pump (1), slip casting in explosive hole, when return pipe (5) overfall, stop slip casting;
D., after grout cures, open air pump (2), in explosive hole, be pressed into air by air injection pipe (8);
E. open the valve (7) on detector tube (6), detect the gas density in explosive hole by portable watt of inspection instrument, when gas density reaches 9 ~ 10%, close air pump (2) and valve (7);
F. starting ignition device (3), ignites the gas in explosive hole, the coal body around fracturing explosive hole, makes to produce a large amount of cracks in coal body, runs through the drainage holes around explosive hole;
G. open valve (7), detector tube (6) is incorporated to gas pumping pipe network and carries out gas pumping, complete the operation of an explosive hole.
2. gas blastingfracture coal body enhanced gas extraction method in one boring according to claim 1, is characterized in that: the pipeline section that described detector tube (6) is positioned at coal seam section is evenly distributed with some apertures.
3. gas blastingfracture coal body enhanced gas extraction method in one boring according to claim 1, is characterized in that: described air injection pipe (8) 0.5m longer than return pipe (5).
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| CN104612746A (en) * | 2015-01-12 | 2015-05-13 | 中国矿业大学 | Cutting-exploding coupled coal anti-reflection method in drilled hole |
| CN104632270A (en) * | 2015-01-06 | 2015-05-20 | 中国矿业大学 | Oscillating impulse type high-energy gas fracturing and heat injection alternating gas-extracting method |
| CN104632271A (en) * | 2015-01-12 | 2015-05-20 | 中国矿业大学 | Method for increasing permeability in drilling holes in cold expansion and heat driving mode |
| CN105909302A (en) * | 2016-04-21 | 2016-08-31 | 中国矿业大学 | System and process for coal seam permeability improvement by inducing hole drilling extraction later-period gas burning explosion |
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| CN104632270A (en) * | 2015-01-06 | 2015-05-20 | 中国矿业大学 | Oscillating impulse type high-energy gas fracturing and heat injection alternating gas-extracting method |
| CN104632270B (en) * | 2015-01-06 | 2016-11-16 | 中国矿业大学 | A kind of oscillating impulse formula high enegry gas fracturing and heat injection alternation mash gas extraction method |
| CN104533514A (en) * | 2015-01-12 | 2015-04-22 | 中国矿业大学 | Method for thermal displacement type forced gas drainage in drill holes |
| CN104612746A (en) * | 2015-01-12 | 2015-05-13 | 中国矿业大学 | Cutting-exploding coupled coal anti-reflection method in drilled hole |
| CN104632271A (en) * | 2015-01-12 | 2015-05-20 | 中国矿业大学 | Method for increasing permeability in drilling holes in cold expansion and heat driving mode |
| CN104533514B (en) * | 2015-01-12 | 2017-07-07 | 中国矿业大学 | Hot displacement type enhanced gas extraction method in one kind drilling |
| CN105909302A (en) * | 2016-04-21 | 2016-08-31 | 中国矿业大学 | System and process for coal seam permeability improvement by inducing hole drilling extraction later-period gas burning explosion |
| CN105927268A (en) * | 2016-04-21 | 2016-09-07 | 中国矿业大学 | Gas explosion coal seam permeability increasing extraction method in borehole in later period of induction extraction |
| CN105927268B (en) * | 2016-04-21 | 2017-12-15 | 中国矿业大学 | Gas fires the anti-reflection pumping method in coal seam in a kind of induction extraction later stage drilling hole |
| CN106351613A (en) * | 2016-10-14 | 2017-01-25 | 安徽理工大学 | Continuous gas extraction method under condition of multiple times of repeated blasting disturbance of coals |
| CN107701163A (en) * | 2017-10-11 | 2018-02-16 | 山东科技大学 | The blast of a kind of thermal agitation and drilling gas cooperates the secondary permeability improvement device in coal seam and method |
| WO2019184148A1 (en) * | 2018-03-27 | 2019-10-03 | 山东科技大学 | Efficient water injection method for low-permeability coal seam |
| WO2019242190A1 (en) * | 2018-06-22 | 2019-12-26 | 中国矿业大学 | Multi-stage combustion shock wave-induced cracked coal body and heat injection alternating reinforced gas extraction method |
| US10808514B2 (en) | 2018-06-22 | 2020-10-20 | China University Of Mining And Technology | Multi-stage combustion impact wave coal mass cracking and heat injection alternating intensified gas extracting method |
| CN109854210A (en) * | 2019-03-05 | 2019-06-07 | 重庆大学 | Using the gas pumping method and extraction system of liquid nitrogen and steam fracturing coal seam |
| CN110925015A (en) * | 2019-12-16 | 2020-03-27 | 中国矿业大学(北京) | Technology for enhancing permeability of coal seam by utilizing water jet to drill cavity gas explosion |
| CN110925015B (en) * | 2019-12-16 | 2021-09-28 | 中国矿业大学(北京) | Technology for enhancing permeability of coal seam by utilizing water jet to drill cavity gas explosion |
| WO2021128933A1 (en) * | 2019-12-27 | 2021-07-01 | 翟成 | Fluidized mining method for in-situ pyrolysis gas of high gas coal seam |
| CN112943348A (en) * | 2021-03-18 | 2021-06-11 | 华能煤炭技术研究有限公司 | Comprehensive prevention and control system and method for rock burst and gas of coal face |
| CN112943348B (en) * | 2021-03-18 | 2023-08-08 | 华能煤炭技术研究有限公司 | Comprehensive control system and control method for rock burst and gas of coal face |
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