CN104594866A - New method for rapid gas drainage technology based on low permeability coal bed gas phase fracturing - Google Patents

New method for rapid gas drainage technology based on low permeability coal bed gas phase fracturing Download PDF

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Publication number
CN104594866A
CN104594866A CN201410608701.3A CN201410608701A CN104594866A CN 104594866 A CN104594866 A CN 104594866A CN 201410608701 A CN201410608701 A CN 201410608701A CN 104594866 A CN104594866 A CN 104594866A
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gas
gas phase
pressure break
coal seam
coal
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Inventor
曹运兴
张军胜
田林
曹永恒
石玢
郭德涛
马兵
孙丙周
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HENAN SHENHUA ENERGY ENGINEERING Co Ltd
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HENAN SHENHUA ENERGY ENGINEERING Co Ltd
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Priority to CN201410608701.3A priority Critical patent/CN104594866A/en
Publication of CN104594866A publication Critical patent/CN104594866A/en
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    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/25Methods for stimulating production
    • E21B43/26Methods for stimulating production by forming crevices or fractures
    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21FSAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
    • E21F7/00Methods or devices for drawing- off gases with or without subsequent use of the gas for any purpose

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Drilling And Exploitation, And Mining Machines And Methods (AREA)

Abstract

Provided is a new method for rapid gas drainage technology based on low permeability coal bed gas phase fracturing. 'High pressure gas fracturing' is adopted as a basic method, the state of the crustal stress of a coal bed is changed, fractures of the coal bed are increased and the gas permeability of the coal bed is improved, gas desorption and release are accelerated, gas pressure and content are reduced, coal and gas outburst dangerousness is remitted, and coal and gas outbursts are prevented from occurring. The method comprises the specific steps that drilling is conducted on the to-be-tapped coal bed of a gas outburst high dangerous working face, a gas phase fracturing rod is put into a hole drilled, the hole drilled is sealed, a high pressure tube is started so that high pressure gas can be released to fracture the coal bed, and the high pressure tube is taken out later. The new method for the rapid gas drainage technology based on the low permeability coal bed gas phase fracturing can be applied to roadway coal tunneling and a working face to prevent the coal and gas outbursts, and can also be applied to the prevention of rock and CO<2> outbursts and mining dynamic disasters such as rock bursts.

Description

A kind of new method based on the quick extraction technology of hypotonic coal seam gas phase pressure break gas
Technical field
The invention belongs to control coal and gas prominent technical field, relate to the method for the control coal and gas prominent of a kind of change primitive coalbed crustal stress states before high gas layer exploitation and gas bearing state.
Background technology
Coal and gas prominent is the most serious disaster of world's coal industry.The coal and gas prominent disaster of China takes place frequently, and along with the increase of coal mining depth, geostatic stress and gas pressure also increase thereupon, and gas bearing capacity increases.Gas Disaster is produced to the safe coal of China and is brought grave danger, seriously governs the sustainable development of coal industry.
Change the main technological approaches that crustal stress states, increase gas permeability, reduction gas pressure and gas bearing capacity are control coal and gas prominent.The measure of China's current control coal and gas prominent mainly contains regional outburst prevention measures and locality outburst prevention measures, comprises the methods such as the intensive drilling technique in this coal seam, hydraulic fracturing technology, hydraulic flushing technology, hydraulic turbulence, deep hole standing shot technology.These technical methods serve the effect of control coal and gas prominent to a certain extent, but still have certain limitation.As explosive blasting extinction measure increases direct disaster incidence, the easy crossfire of fracturing even destroys extraction system.
Summary of the invention
The object of this invention is to provide a kind of control coal and gas prominent method, high pressure vapor fracturing process provided by the invention can greatly alleviate geostatic stress concentration phenomenon, open coal seam cleat system, strengthen the gas permeability in coal seam, improve desorption of mash gas speed and extraction efficiency, reduce gas pressure and gas bearing capacity, alleviate gas outburst risk.
The following technical scheme of main employing:
The method adopts gas phase pressure break pole pair high methane dangerous seam with potential to carry out the effect of gas phase pressure break; In the middle of described gas phase pressure break bar be cavity to store the high pressure body of gases at high pressure, its one end is snifting valve, is provided with several fumaroles; The other end is charge valve, and it is connected with can for the inflation end injecting gases at high pressure, and inflation end is inner is equipped with the pressure inlet stretching into main body in high-voltage tube cavity, and with outside electrode lead body; When carrying out gas phase pressing crack construction, external exploder is by wire connecting electrode and pressure inlet and open quick-fried gases at high pressure, and gases at high pressure act on coal seam and pressure break coal seam.
Further, it comprises the following steps:
A holes: implement boring in the coal seam of high methane outburst face, and hole dark 5 ~ 200 meters or darker, aperture is less than or equal to 200 millimeters;
B high-voltage tube is put: the high-voltage tube being no less than 1 is inserted boring, connects upper conductor and draws outside boring;
C. borehole sealing: use hole sealing device sealing boring;
D. start: lead-in wire of blowing out connects booster, and start booster, high-voltage tube discharges gases at high pressure and carries out gas phase pressure break to coal seam;
E. dismantle hole sealing device, take out high-voltage tube.
Further, in step a, high methane is given prominence on driving face, and along cloth hole, tunnelling direction staged fracturing, but boring should be continuously uninterrupted, should not occur borehole fracturing clear band, single hole depth 1-200 rice.
Further, in step a, on high methane stope, along cloth hole, roadway workface direction staged fracturing, pitch-row 2-30 rice, single hole depth 2-200 rice.
Further, in step a, between pressure break boring, be furnished with the auxiliary bore hole for pressure release or mash gas extraction.
Further, the spacing of described auxiliary bore hole can according to pressure break demand arrangement pitch voluntarily, and the spacing of auxiliary bore hole and pressure break boring is not less than 1 meter.
Further, in step c, described hole sealing device is arranged in boring and is not less than 3 meters of depths apart from aperture.
Its beneficial effect is:
Carry out gas phase pressure break to coal seam, geostatic stress is redistributed, homogenising is stress concentration phenomenon partly, effectively can alleviate intensity and the frequency of coal and gas prominent.
Gas phase pressure break is carried out to coal seam, original hugger-fissure system in coal seam can be restarted, strengthen the gas permeability in coal seam greatly, improve desorption of mash gas speed and extraction efficiency, quick reduction gas bearing capacity and gas pressure, alleviate Gas Outburst tendentiousness, and then the generation of control Gas Outburst.
Coal seam pressure relief and elimination are given prominence to: coal seam crustal stress states after pressure break changes thereupon, gas fast desorption and discharge, and gas pressure and gas bearing capacity reduce, and gas outburst risk is alleviated;
Gas release is alleviated outstanding: connect extraction pipeline and boring, with negative pressure or the continuous extraction borehole gas pressure relief of normal pressure, can reduce gas pressure and content further, control coal and gas prominent;
The useful effect radius of a pressure break destressing borehole can reach 1 ~ 10 meter through test, even large to 50 meters with far.The spacing of pressure break boring should at 1 ~ 50 meter.
Different from explosive pre-splitting method, using the present invention without the need to arranging large aperture control hole between pressure break boring, having simplified pressing crack construction and extraction system cost.
When needs short-term rapid outburst elimination, can be used for reducing gas pressure and gas bearing capacity, auxiliary bore hole spacing 1 ~ 20 meter fast by intensive layout auxiliary bore hole between pressure break boring, or nearer.
Generally apart from, 1 ~ 20 meter, aperture, hole sealing device is set, by tight for pressure break borehole sealing in pressure break boring.
The main purpose that pressure break boring arranges sealing of hole makes pre-splitting hole tight closure and arranges borehole gases pressure monitor, immense pressure useful effect that boring inner high voltage gas pressure break generates can be made in coal seam, and do not discharge boring.
After coal bed fracturing, open hole sealing device when borehole fracturing gas pressure reduces to 0.2MPa, ensure bore operation Environmental security.
High pressure vapor pressure break coal seam technology, can form effective crack and unload trim ring, unload in trim ring in crack, can improve gas pumping speed, and control coal and gas prominent, realizes the effect of Comprehensive Gas Control.
High pressure vapor pressure break coal seam technology, can be applied to control coal and gas prominent, also can be applied to the anti-reflection quick enhanced gas extraction of low air permeability coal seam.
High pressure vapor pressure break coal seam technology, has fast pressure relief effect on a large scale, has the effect alleviating bump and Rock projection, can be applied to control bump, and Rock projection and CO2 give prominence to.
High pressure vapor pressure break coal seam technology, has quick-speed large-scale fracturing and release effect, can be applied to coal mining and rock mining.
The present invention can control within the scope of 20 ~ 280MPa to the gas phase detonation pressure of coal body, and this pressure is far smaller than the detonation pressure of explosive, can cause coal fracturing instead of comminuted destruction.
Use high pressure vapor fracturing technique control coal and gas prominent not have naked light to produce, itself does not have explosivity, outside flammable and combustion-supporting property, also has the effect suppressing blast and burning, can reach the basic demand of essential safety, safe and reliable.
The present invention, for preventing and treating coal and gas prominent and the strong extraction of gas, is all of great importance to safety of coal mines, gas control, energy-conservation, economic benefit, social stability etc.This technology has and reduces gas pressure fast, effectively improves gas density, quick mash gas extraction, shortens the gas pre-drainage time, reduces gas pumping cost, improve coal production efficiency, enhance the comprehensive benefit of coal mine production safety.Therefore, the present invention is significant to control of coalmine gas.
Accompanying drawing explanation
Fig. 1 is the structural representation of the gas phase pressure break bar that the present invention uses.
In Fig. 1: 1, snifting valve; 2, fumarole; 3, sheet is sheared; 4, sealing ring; 5, gas phase fracturing unit; 6, pressure inlet; 7, electrode; 8, electrode lead body; 9, insulation sleeve; 10, insulation spacer; 11, two poles; 12 filling channels; 13, charge valve.
Detailed description of the invention:
The method adopts gas phase pressure break pole pair high methane dangerous seam with potential to carry out the effect of gas phase pressure break; In the middle of described gas phase pressure break bar be cavity to store the high pressure body of gases at high pressure, its one end is snifting valve 1, is provided with several fumaroles 2; The other end is charge valve 13, and it is connected with can for the inflation end injecting gases at high pressure, and inflation end is inner is equipped with the pressure inlet 6 stretching into main body in high-voltage tube cavity, and with outside electrode 11 lead body; When carrying out gas phase pressing crack construction, external exploder is by wire connecting electrode and pressure inlet 6 and open quick-fried gases at high pressure, and gases at high pressure act on coal seam and pressure break coal seam.
Certain ore deposit 1300 work plane assists return airway to test:
Meet head on to hit exactly layout 1 pressure break hole, pressure break hole left and right sides arranges 3 via holes respectively, and in the drill site of left and right, 12 borings are as via hole, add up to 18 via holes.Drill site via hole can before fracturing work pore-forming, via hole of meeting head on must be constructed after pressure break.
Gas phase pressing crack construction is carried out 7 times at this driving face, carry out 7 P. drechsleri, on June 20th, 2013, on July 19th, 2013, on August 1st, 2013, on September 19th, 2013, on October 19th, 2013, on November 10th, 2013, on December 1st, 2013 respectively, the statistics front tunnel of pressure break adopts conventional intensive inhaling as tunneling measure and intensive gas release boring extinction technology of meeting head on, within the scope of driving 140m, K1 value exceedes threshold 4 times, and hundred meters of number of times that exceed standard are 2.86 times.
After implementing gas phase pressure break, K1 value declines obviously, and after pressure break within the scope of tunnelling 420m, K1 value exceedes threshold 1 time, and hundred meters of number of times that exceed standard are 0.24 time, reduce 90%, successful, and after gas phase pressure break, safety tunnels 420m continuously.

Claims (7)

1., based on a new method for the quick extraction technology of hypotonic coal seam gas phase pressure break gas, the method adopts gas phase pressure break pole pair high methane dangerous seam with potential to carry out the effect of gas phase pressure break; In the middle of described gas phase pressure break bar be cavity to store the high pressure body of gases at high pressure, its one end is snifting valve, is provided with several fumaroles; The other end is charge valve, and it is connected with can for the inflation end injecting gases at high pressure, and inflation end is inner is equipped with the pressure inlet stretching into main body in high-voltage tube cavity, and with outside electrode lead body, described electrode is enclosed with insulation sleeve and insulation spacer; When carrying out gas phase pressing crack construction, external exploder is by wire connecting electrode and pressure inlet and open quick-fried gases at high pressure, and gases at high pressure act on coal seam and pressure break coal seam.
2. a kind of new method based on the quick extraction technology of hypotonic coal seam gas phase pressure break gas according to claim 1, is characterized in that comprising the following steps:
A holes: implement boring in the coal seam of high methane outburst face, and hole dark 5 ~ 200 meters or darker, aperture is less than or equal to 200 millimeters;
B high-voltage tube is put: the high-voltage tube being no less than 1 is inserted boring, connects upper conductor and draws outside boring;
C. borehole sealing: use hole sealing device sealing boring;
D. start: lead-in wire of blowing out connects booster, and start booster, high-voltage tube discharges gases at high pressure and carries out gas phase pressure break to coal seam;
E. dismantle hole sealing device, take out high-voltage tube.
3. a kind of new method based on the quick extraction technology of hypotonic coal seam gas phase pressure break gas according to claim 2, it is characterized in that in step a, high methane is given prominence on driving face, along cloth hole, tunnelling direction staged fracturing, but boring should be continuously uninterrupted, should not there is borehole fracturing clear band, single hole depth 1-200 rice.
4. a kind of new method based on the quick extraction technology of hypotonic coal seam gas phase pressure break gas according to claim 2, it is characterized in that in step a, on high methane stope, along cloth hole, roadway workface direction staged fracturing, pitch-row 2-30 rice, single hole depth 2-200 rice.
5. a kind of new method based on the quick extraction technology of hypotonic coal seam gas phase pressure break gas according to claim 2, is characterized in that in step a, is furnished with the auxiliary bore hole for pressure release or mash gas extraction between pressure break boring.
6. a kind of new method based on the quick extraction technology of hypotonic coal seam gas phase pressure break gas according to claim 5, it is characterized in that the spacing of described auxiliary bore hole can according to pressure break demand arrangement pitch voluntarily, the spacing of auxiliary bore hole and pressure break boring is not less than 1 meter.
7. a kind of new method based on the quick extraction technology of hypotonic coal seam gas phase pressure break gas according to claim 2, is characterized in that in step c, and described hole sealing device is arranged in boring and is not less than 3 meters of depths apart from aperture.
CN201410608701.3A 2014-10-31 2014-10-31 New method for rapid gas drainage technology based on low permeability coal bed gas phase fracturing Pending CN104594866A (en)

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104612644A (en) * 2014-11-18 2015-05-13 山西潞安矿业(集团)有限责任公司 Gas phase fracturing and fast gas extraction method for low permeability coal bed
CN105003242A (en) * 2015-08-19 2015-10-28 山西鸿海科贸有限公司 Device capable of increasing fractures of coal-bed gas well
CN105298534A (en) * 2015-11-25 2016-02-03 中国矿业大学(北京) Light dydrocarbon explosion fracturing anti-reflection device
CN105422074A (en) * 2015-11-23 2016-03-23 中北大学 Electric initiating liquid propellant dynamic fracturing device
CN106382108A (en) * 2016-10-21 2017-02-08 河南神华能源工程有限公司 Fracturing and blockage-removal production increase method for oil-gas well based on CO2 gas phase fracturing technique
CN107179029A (en) * 2017-05-16 2017-09-19 深圳市瑞利源工程技术有限公司 A kind of gases at high pressure static expanding broken rock device and rock breaking method
CN107420080A (en) * 2017-06-27 2017-12-01 山西潞安工程有限公司 Wear pre-draining borehole gas phase fracturing process before layer pick in a kind of hypotonic coal seam Di Chou lanes
CN108131120A (en) * 2017-12-12 2018-06-08 中国石油天然气股份有限公司 Completion tubular column, completion method and gas injector mechanism
CN109239770A (en) * 2018-09-12 2019-01-18 中国矿业大学 One kind is with CO2Big gun is the working face lateral wall seismic detection method of focus
WO2019184147A1 (en) * 2018-03-27 2019-10-03 山东科技大学 Method for efficiently preventing impact ground pressure for low gas-permeability coal seam

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CN203685187U (en) * 2013-10-17 2014-07-02 湖南汉寿中煤科技有限公司 Oriented CO2 air cannon device
CN103993880A (en) * 2014-05-20 2014-08-20 湖南汉寿煤矿机械有限公司 Heater of electric firing head and liquid CO2 phase-change fracturing equipment applying heater

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WO1998010169A1 (en) * 1996-09-06 1998-03-12 Alan Colin Mcgowan Blasting device
CN2429630Y (en) * 2000-06-05 2001-05-09 孙朝启 Drawing expansion bar
WO2009039776A1 (en) * 2007-09-19 2009-04-02 Institute Of Rock And Soil Mechanice, Chinese Academy Of Sciences An exploitation system and method for displacing coal bed gas by mixed gas through a pumping drainage way which is under a well
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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104612644A (en) * 2014-11-18 2015-05-13 山西潞安矿业(集团)有限责任公司 Gas phase fracturing and fast gas extraction method for low permeability coal bed
CN105003242A (en) * 2015-08-19 2015-10-28 山西鸿海科贸有限公司 Device capable of increasing fractures of coal-bed gas well
CN105422074A (en) * 2015-11-23 2016-03-23 中北大学 Electric initiating liquid propellant dynamic fracturing device
CN105422074B (en) * 2015-11-23 2018-02-02 中北大学 Electric initiating liquid medicine dynamic fracturing equipment
CN105298534A (en) * 2015-11-25 2016-02-03 中国矿业大学(北京) Light dydrocarbon explosion fracturing anti-reflection device
CN106382108A (en) * 2016-10-21 2017-02-08 河南神华能源工程有限公司 Fracturing and blockage-removal production increase method for oil-gas well based on CO2 gas phase fracturing technique
CN106382108B (en) * 2016-10-21 2019-07-16 河南神华能源工程有限公司 Well fracturing and removal and stimulation method based on CO2 gas phase fracturing technique
CN107179029B (en) * 2017-05-16 2019-05-31 深圳市瑞利源工程技术有限公司 A kind of high pressure gas static expanding broken rock device and rock breaking method
CN107179029A (en) * 2017-05-16 2017-09-19 深圳市瑞利源工程技术有限公司 A kind of gases at high pressure static expanding broken rock device and rock breaking method
CN107420080A (en) * 2017-06-27 2017-12-01 山西潞安工程有限公司 Wear pre-draining borehole gas phase fracturing process before layer pick in a kind of hypotonic coal seam Di Chou lanes
CN108131120A (en) * 2017-12-12 2018-06-08 中国石油天然气股份有限公司 Completion tubular column, completion method and gas injector mechanism
CN108131120B (en) * 2017-12-12 2019-11-08 中国石油天然气股份有限公司 Completion tubular column, completion method and gas injector mechanism
WO2019184147A1 (en) * 2018-03-27 2019-10-03 山东科技大学 Method for efficiently preventing impact ground pressure for low gas-permeability coal seam
CN109239770A (en) * 2018-09-12 2019-01-18 中国矿业大学 One kind is with CO2Big gun is the working face lateral wall seismic detection method of focus

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Application publication date: 20150506