CN108301811A - A kind of efficient pumping method of hypotonicity coal-bed gas - Google Patents

A kind of efficient pumping method of hypotonicity coal-bed gas Download PDF

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Publication number
CN108301811A
CN108301811A CN201810255559.7A CN201810255559A CN108301811A CN 108301811 A CN108301811 A CN 108301811A CN 201810255559 A CN201810255559 A CN 201810255559A CN 108301811 A CN108301811 A CN 108301811A
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China
Prior art keywords
gas
coal
pressure
drilling
hypotonicity
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Withdrawn
Application number
CN201810255559.7A
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Chinese (zh)
Inventor
张延松
李伟
孟祥豹
孟祥军
张新燕
陈海燕
刘博�
杜文洲
王相
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Yankuang Group Corp Ltd
Shandong University of Science and Technology
Yanzhou Coal Mining Co Ltd
Yanzhou Coal Industry Co Ltd
Original Assignee
Yankuang Group Corp Ltd
Shandong University of Science and Technology
Yanzhou Coal Industry Co Ltd
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Application filed by Yankuang Group Corp Ltd, Shandong University of Science and Technology, Yanzhou Coal Industry Co Ltd filed Critical Yankuang Group Corp Ltd
Priority to CN201810255559.7A priority Critical patent/CN108301811A/en
Publication of CN108301811A publication Critical patent/CN108301811A/en
Withdrawn legal-status Critical Current

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    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP 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
    • E21B43/006Production of coal-bed methane
    • EFIXED CONSTRUCTIONS
    • E21EARTH 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

Abstract

The present invention proposes a kind of efficient pumping method of hypotonicity coal-bed gas, includes the following steps:Step 1: coal body mechanical property measures;Step 2: determining the highest gas injection pressure of high pressure gas gas injection;Step 3: coal body drills;Step 4: Uncoincided charge;Step 5: reserved pressure duct in drilling;Step 6: drilling and sealing;Step 7: high pressure gas gas injection;Step 8: ignition charge presplitting is anti-reflection;Step 9: gas pumping.Beneficial effects of the present invention:It is construction safety, reliable, reasonable Arrangement drills in waiting for working seam, inject high pressure gas (mixed gas of hydrogen and air), realize hydrogen and explosive detonation collaboration, the porosity for waiting for working seam is significantly greatly increased, presplitting is anti-reflection radius is big, effect is good, big to hypotonicity coal bed gas extraction radius, and the extracting result of hypotonicity coal-bed gas is greatly improved.

Description

A kind of efficient pumping method of hypotonicity coal-bed gas
Technical field
The present invention relates to coal bed gas extraction technical fields, more particularly to a kind of efficient extraction of hypotonicity coal-bed gas Method.
Background technology
Coal still occupies very important status in China's energy consumption structure, 2016, and consumption of coal proportion is 62.6%, it is contemplated that 2017 about 60% or so.China coal seam is commonly low-permeability coal seam, and compared to foreign countries, China is oozed in coal seam Permeability generally wants the small 2-3 order of magnitude, hypotonicity to cause many coal mine rock burst accidents in China, coal and gas prominent thing Therefore take place frequently, while highly gassy mine due to coal seam permeability it is relatively low, cause gas pumping difficult, these problems all seriously hinder China's coal-mine highly effective and safe is exploited.In the coal resources that China has found, there is nearly half buried depth to be more than 1000m, it is old at present The gradually atrophy of mining area coal, the exploitation of coal resources in China will be transferred to Deep Mine exploitation in the future.Deep Mine faces highland and answers The case where power, high methane pressure, China coal seam is commonly low-permeability coal seam in addition, easily causes bump, coal and gas The disaster accidents such as prominent seriously restrict the exploitation of mine high-efficiency intensifying and safety in production.Coal mine low-permeability coal seam is also referred to as Low air permeability coal seam needs to ensure the exploitation of low air permeability coal seam high-efficiency intensifying and safety in production to hypotonicity coal seam watt This efficient pumping method is studied.
Currently, the anti-reflection measure of low air permeability coal seam presplitting mainly include deep hole standing shot, hydrofracturing, hydraulic flushing in hole, The methods of Mining Protective Seam, hydraulic slotted liner technique.Wherein deep hole standing shot to drill neighbouring coal seam fried it is very broken, but to from The slightly remote local presplitting effect of drilling declines rapidly, and presplitting radius is smaller, and effect is bad;Additionally, due to the induced detonation of coal mining explosive Distance is smaller, and to prevent from miss-firing, site operation needs primacord to be coupled, therefore, site operation trouble;Besides explosive presplitting, It is possible that cause the region gas explosion be connected by crack, it is dangerous.If hydraulic fracturing hydraulic pressure is small, crack expansion is limited, in advance It is bad to split effect;If hydraulic pressure is big, high pressure water can be flowed out from larger crack, and presplitting is uneven, and effect is bad;And high pressure water exists Flowing in coal seam is uncontrollable.Hydraulic flushing in hole is drilled by sluicing, wash boring hole wall while expanding bore diameter Coal dust, so that the wall of a borehole is had better permeability, due to this method for improve gas permeability of coal seam effect it is very small, at present substantially not It uses again.Mining Protective Seam often closes on liberation layer thickness very little due to the limitation of condition of coal seam occurrence, it is difficult to it exploits, or Coal quality is poor, does not close on Protective Coal Seam without extraction value or even many coal seams so that the technology can not use.Hydraulic slotted liner technique It is limited by equipment so that the implementing process of this technology is complicated, it is difficult to promote and apply at the scene.
Invention content
The purpose of the present invention is to provide a kind of efficient pumping methods of hypotonicity coal-bed gas, solve current hypotonicity The technical problem that coal bed gas extraction radius is small and effect is poor.
The present invention provides a kind of efficient pumping method of hypotonicity coal-bed gas, includes the following steps:
Step 1: coal body mechanical property measures
Coal sample is taken in waiting for working seam, measures the compression strength of coal body, and determination waits for working seam close to track crossheading, glue The crisp band depth of band crossheading position coal body pressure;
Step 2: determining the highest gas injection pressure of high pressure gas gas injection
By the compression strength of coal body divided by the 1.5 highest gas injection pressure as follow-up high pressure gas gas injection;
Step 3: coal body drills
Respectively along track crossheading, adhesive tape crossheading extending direction to waiting for equidistant horizontal drilling in working seam, drilling Depth is 0.3 times of coal working face length, and the vertical height of drilling is 0.5 times of coal working face height;
Step 4: Uncoincided charge
Explosive is packed into drilling using Uncoincided charge mode;
Step 5: reserved pressure duct in drilling
Reserved pressure duct in drilling, pressure duct is located at 0.5 to 0.6 times that the length in drilling is drilling depth, high Drilling is stretched out in the end on pressure pipe road;
Step 6: drilling and sealing
By drilling and sealing, using cement material sealing of hole, the length of cementing is 0.2 to 0.3 times of drilling depth, cement The length of sealing of hole is greater than the crisp band depth of coal body pressure;
Step 7: high pressure gas gas injection
High pressure gas is injected into drilling by pressure duct, the pressure for injecting high pressure gas is gradually increased to highest gas injection Pressure is simultaneously kept, and highest gas injection pressure by being determined in step 2, after obviously becoming smaller and stablize still protect by injection high-pressure gas flow It holds highest gas injection pressure several hours, high pressure gas is the mixed gas of hydrogen and air, the volume point of hydrogen in mixed gas Number is 28.6%;
Step 8: ignition charge presplitting is anti-reflection
It is kept in the time of highest gas injection pressure in injection high pressure gas, ignites the explosive in drilling, coal seam carried out pre- It splits anti-reflection;
Step 9: gas pumping
Pressure duct is connected into extraction pipeline, extraction waits for the gas in working seam.
Further, in step 3, the level interval of adjacent drilling is 20m, the drilling nearest apart from coal working face away from It is 10m, bore diameter 96mm from coal working face.
Further, in step 4, the loaded length of explosive is 0.5 to 0.7 times of drillable length.
Further, in step 5, it is 0.5m to 1m that the length of drilling is stretched out in the end of pressure duct.
Further, in step 6, the ratio of cement and water is 1 in cement material:0.2 to 1:0.5.
Further, in step 7, injection high-pressure gas flow still keeps highest gas injection pressure after obviously becoming smaller and stablize 6 hours of power.
Compared with prior art, the efficient pumping method of hypotonicity coal-bed gas of the invention and have the characteristics that with it is excellent Point:
The efficient pumping method of hypotonicity coal-bed gas of the present invention, it is construction safety, reliable, in waiting for working seam rationally Arrangement drilling, injection high pressure gas (mixed gas of hydrogen and air) realize hydrogen and explosive detonation collaboration, are significantly greatly increased and wait for The porosity of working seam, presplitting is anti-reflection radius is big, effect is good, big to hypotonicity coal bed gas extraction radius, is greatly improved The extracting result of hypotonicity coal-bed gas.
After the specific implementation mode of the present invention is read in conjunction with the figure, the features and advantages of the invention will become clearer.
Description of the drawings
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below There is attached drawing needed in technology description to be briefly described, it should be apparent that, the accompanying drawings in the following description is the present invention Some embodiments for those of ordinary skill in the art without creative efforts, can also basis These attached drawings obtain other attached drawings.
Fig. 1 is the flow chart of the efficient pumping method of hypotonicity coal-bed gas of the embodiment of the present invention;
Fig. 2 is the borehole pattern of the efficient pumping method of hypotonicity coal-bed gas of the embodiment of the present invention;
Wherein, 1, coal working face, 2, track crossheading, 3, adhesive tape crossheading, 4, wait for working seam, 5, drilling.
Specific implementation mode
As shown in Figure 1 and Figure 2, the present embodiment provides a kind of efficient pumping methods of hypotonicity coal-bed gas, including following step Suddenly:
Step 1: coal body mechanical property measures
Coal sample is taken in waiting for working seam 4, measures the compression strength of coal body, determination waits for working seam 4 close to track crossheading 2, the 3 crisp band depth of position coal body pressure of adhesive tape crossheading.
Step 2: determining the highest gas injection pressure of high pressure gas gas injection
By the compression strength of coal body divided by the 1.5 highest gas injection pressure as follow-up high pressure gas gas injection.
Step 3: coal body drills
Respectively along track crossheading 2, adhesive tape crossheading 3 extending direction to waiting for equidistant horizontal drilling in working seam 4, drill 5 depth is 0.3 times of 1 length of coal working face, and 5 vertical height of drilling is 0.5 times of 1 height of coal working face.It is adjacent The level interval of drilling 5 is 20m, and the drilling 5 nearest apart from coal working face 1 is 10m, bore diameter apart from coal working face 1 For 96mm.
Step 4: Uncoincided charge
Explosive is packed into drilling 5 using Uncoincided charge mode, the loaded length of explosive be 5 length of drilling 0.5 to 0.7 times.
Step 5: reserving pressure duct in drilling 5
Pressure duct is reserved in drilling 5, pressure duct is located at 0.5 to 0.6 times that the length in drilling 5 is 5 depth of drilling, Drilling 5 is stretched out in the end of pressure duct, and it is 0.5m to 1m that the length of drilling 5 is stretched out in the end of pressure duct.
Step 6: 5 sealing of holes of drilling
To drill 5 sealing of holes, and using cement material sealing of hole, the ratio of cement and water is 1 in cement material:0.2 to 1:0.5. The length of cementing is 0.2 to 0.3 times of 5 depth of drilling, and the length of cementing is greater than the crisp band depth of coal body pressure.
Step 7: high pressure gas gas injection
High pressure gas is injected into drilling 5 by pressure duct, the pressure for injecting high pressure gas is gradually increased to highest note Atmospheric pressure is simultaneously kept, and highest gas injection pressure is injected after high-pressure gas flow obviously becomes smaller and stablizes still by being determined in step 2 It is kept for 6 hours of highest gas injection pressure, high pressure gas is the mixed gas of hydrogen and air, the volume point of hydrogen in mixed gas Number is 28.6%.
Step 8: ignition charge presplitting is anti-reflection
It is kept in the time of highest gas injection pressure in injection high pressure gas, ignites the explosive in drilling 5, coal seam carried out pre- It splits anti-reflection.
Step 9: gas pumping
Pressure duct is connected into extraction pipeline, extraction waits for the gas in working seam 4.
The efficient pumping method of hypotonicity coal-bed gas of the present embodiment, effect and high pressure of the high pressure gas in drilling In terms of hydrogen and explosive detonation synergistic principle are embodied in following six.
First, after in high pressure hydrogen injection hole 5, high pressure hydrogen enter wait for crack in working seam 4, rimala, hole, Expansion work while micropore, semiclosed hole so that rimala expands unicom into larger crack, while hole, micropore, Semiclosed hole extension becomes crack and larger hole so that the mutually unicom such as initial fissure, regeneration crack, hole forms ventilative Property network, improve and wait for the gas permeability of working seam 4.
Second is that in the gas permeability networks that mutually unicom is formed such as initial fissure, regeneration crack, hole, high pressure hydrogen changes The occurrence status (adsorption/desorption) for waiting for methane in working seam 4 makes first of dissociating in drilling, initial fissure, regeneration crack, hole The amount of alkane becomes smaller, and then makes to wait for that the methane concentration in working seam is less than its explosion limit, improves safety.
Third, after injection high-pressure gas flow obviously becomes smaller and stablizes relatively in drilling 5, it is 6 small persistently to inject high pressure gas When so that high pressure gas by hydrostatic pressure, can preferably act on the cracks in coal seam of unicom and non-unicom, hole, micropore, Semiclosed hole makes cracks in coal seam, hole net unicom network further develop, and improves the gas permeability for waiting for working seam 4.
Fourth, since charging means are Uncoincided charge, the detonation wave that explosive charge generates makes to form radial split inside coal seam Gap, high pressure gas and quick-fried raw high pressure gas in drilling 5 penetrate into Radial crack, play gas wedging action, increase crack front end coal body Interior tensile stress can make to wait for that the crack in working seam 4, hole unicom network are further developed, and raising waits for working seam 4 Gas permeability.
Fifth, it is logical to have high pressure gas when explosive charge, in a large amount of quick-fried raw high pressure gas that explosion initial stage generates, with drilling 5 Hydrostatic pressure is crossed in waiting for the cracks in coal seam of unicom and non-unicom in working seam 4, hole, micropore, semiclosed hole, makes coal seam Crack, hole net unicom network further develop, and improve the gas permeability for waiting for working seam 4.
Sixth, in drilling 5 after explosive initiation, the high temperature and pressure of generation can ignite the height of volume fraction 28.6% in drilling 5 Pressure hydrogen explodes jointly, strengthens explosion and acts on the crack of drilling and its periphery unicom, the extension of pore network, improves and wait exploiting The gas permeability in coal seam 4.
By principles above process, the porosity for waiting for working seam 4 can be greatly increased, is conducive to hypotonicity coal seam watt This efficient extraction.
The efficient pumping method of hypotonicity coal-bed gas of the present embodiment, it is construction safety, reliable, in waiting for working seam 4 Reasonable Arrangement drilling 5 is cooperateed with by the detonation of effect and hydrogen and explosive of the high pressure gas in drilling, is significantly greatly increased and waits out The porosity of mining coal seam, presplitting is anti-reflection, and radius is obviously improved, about 15 to 20 meters, and the most common explosive deep hole loosening of coal mine is quick-fried Broken, presplitting is anti-reflection, and the radius of influence is relatively small, about 3 to 5 meters.Using the most common explosive deep hole standing shot of coal mine, if Reach identical antireflective effect, need encryption drilling 5, sometimes for the preferable antireflective effect of acquisition, it is also necessary to implement a large amount of Control drilling, it is meant that the increase of labor intensity and the reduction of efficiency, while also to increase rendrock dosage are meaned It less efficient.The efficient pumping method of hypotonicity coal-bed gas of the present embodiment, to hypotonicity coal bed gas extraction radius Greatly, the extracting result of hypotonicity coal-bed gas is greatly improved.
Certainly, above description is not limitation of the present invention, and the present invention is also not limited to the example above, this technology neck The variations, modifications, additions or substitutions that the technical staff in domain is made in the essential scope of the present invention should also belong to the present invention's Protection domain.

Claims (6)

1. a kind of efficient pumping method of hypotonicity coal-bed gas, which is characterized in that include the following steps:
Step 1: coal body mechanical property measures
Coal sample is taken in waiting for working seam, measures the compression strength of coal body, and determination waits for that working seam is suitable close to track crossheading, adhesive tape The crisp band depth of groove location coal body pressure;
Step 2: determining the highest gas injection pressure of high pressure gas gas injection
By the compression strength of coal body divided by the 1.5 highest gas injection pressure as follow-up high pressure gas gas injection;
Step 3: coal body drills
Respectively along track crossheading, adhesive tape crossheading extending direction to waiting for equidistant horizontal drilling in working seam, the depth of drilling It it is 0.3 times of coal working face length, the vertical height of drilling is 0.5 times of coal working face height;
Step 4: Uncoincided charge
Explosive is packed into drilling using Uncoincided charge mode;
Step 5: reserved pressure duct in drilling
Reserved pressure duct in drilling, pressure duct are located at 0.5 to 0.6 times that the length in drilling is drilling depth, high-voltage tube Drilling is stretched out in the end on road;
Step 6: drilling and sealing
By drilling and sealing, using cement material sealing of hole, the length of cementing is 0.2 to 0.3 times of drilling depth, cementing Length be greater than the crisp band depth of coal body pressure;
Step 7: high pressure gas gas injection
High pressure gas is injected into drilling by pressure duct, the pressure for injecting high pressure gas is gradually increased to highest gas injection pressure And keep, by being determined in step 2, injection high-pressure gas flow is still kept most highest gas injection pressure after obviously becoming smaller and stablize High gas injection pressure several hours, high pressure gas are the mixed gas of hydrogen and air, and the volume fraction of hydrogen is in mixed gas 28.6%;
Step 8: ignition charge presplitting is anti-reflection
It is kept in the time of highest gas injection pressure in injection high pressure gas, ignites the explosive in drilling, presplitting increasing is carried out to coal seam Thoroughly;
Step 9: gas pumping
Pressure duct is connected into extraction pipeline, extraction waits for the gas in working seam.
2. the efficient pumping method of hypotonicity coal-bed gas according to claim 1, it is characterised in that:In step 3, phase The level interval of neighbour's drilling is 20m, and the hole spacing coal working face nearest apart from coal working face is 10m, and bore diameter is 96mm。
3. the efficient pumping method of hypotonicity coal-bed gas according to claim 1, it is characterised in that:In step 4, fry The loaded length of medicine is 0.5 to 0.7 times of drillable length.
4. the efficient pumping method of hypotonicity coal-bed gas according to claim 1, it is characterised in that:It is high in step 5 The length that drilling is stretched out in the end on pressure pipe road is 0.5m to 1m.
5. the efficient pumping method of hypotonicity coal-bed gas according to claim 1, it is characterised in that:In step 6, water The ratio of cement and water is 1 in mud material:0.2 to 1:0.5.
6. the efficient pumping method of hypotonicity coal-bed gas according to claim 1, it is characterised in that:In step 7, note Enter still to keep 6 hours of highest gas injection pressure after high-pressure gas flow obviously becomes smaller and stablizes.
CN201810255559.7A 2018-03-27 2018-03-27 A kind of efficient pumping method of hypotonicity coal-bed gas Withdrawn CN108301811A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109372572A (en) * 2018-12-20 2019-02-22 华北科技学院 A kind of efficient pumping method of low-permeability coal-bed gas
CN109578060A (en) * 2019-02-01 2019-04-05 西安闪光能源科技有限公司 Coal bed gas extraction method based on controllable shock wave technology
CN109723487A (en) * 2019-01-15 2019-05-07 高九华 Air pulsing quantum energy is implanted into presplitting permeability-increasing gas pumping method and device
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

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101644156A (en) * 2009-07-17 2010-02-10 中国矿业大学 Method for weakening coal-rock mass by hydraulic blasting and fracturing
CN101880209A (en) * 2010-06-24 2010-11-10 杜志刚 High-efficiency pollution-free gas explosive tube

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101644156A (en) * 2009-07-17 2010-02-10 中国矿业大学 Method for weakening coal-rock mass by hydraulic blasting and fracturing
CN101880209A (en) * 2010-06-24 2010-11-10 杜志刚 High-efficiency pollution-free gas explosive tube

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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
CN109372572A (en) * 2018-12-20 2019-02-22 华北科技学院 A kind of efficient pumping method of low-permeability coal-bed gas
CN109723487A (en) * 2019-01-15 2019-05-07 高九华 Air pulsing quantum energy is implanted into presplitting permeability-increasing gas pumping method and device
CN109578060A (en) * 2019-02-01 2019-04-05 西安闪光能源科技有限公司 Coal bed gas extraction method based on controllable shock wave technology

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Application publication date: 20180720