AU2015299587A1 - Enhanced phase-change fracking gas extraction method for low-permeability coal bed - Google Patents
Enhanced phase-change fracking gas extraction method for low-permeability coal bed Download PDFInfo
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- 239000003245 coal Substances 0.000 title claims abstract description 99
- 238000000605 extraction Methods 0.000 title claims abstract description 56
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 96
- 238000002347 injection Methods 0.000 claims abstract description 81
- 239000007924 injection Substances 0.000 claims abstract description 81
- 230000008014 freezing Effects 0.000 claims abstract description 53
- 238000007710 freezing Methods 0.000 claims abstract description 53
- 238000000034 method Methods 0.000 claims abstract description 41
- 230000035699 permeability Effects 0.000 claims abstract description 17
- 230000008569 process Effects 0.000 claims abstract description 13
- 230000002708 enhancing effect Effects 0.000 claims abstract description 10
- 230000008859 change Effects 0.000 claims abstract description 5
- 239000007788 liquid Substances 0.000 claims abstract description 5
- 239000007787 solid Substances 0.000 claims abstract description 5
- 238000007789 sealing Methods 0.000 claims description 13
- 230000007704 transition Effects 0.000 claims description 10
- 238000007796 conventional method Methods 0.000 claims description 7
- 239000011440 grout Substances 0.000 claims description 6
- 239000002775 capsule Substances 0.000 claims description 4
- 230000002159 abnormal effect Effects 0.000 claims description 3
- 230000007423 decrease Effects 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 6
- 238000005553 drilling Methods 0.000 abstract description 5
- 230000007613 environmental effect Effects 0.000 abstract 1
- 239000000155 melt Substances 0.000 abstract 1
- 238000010309 melting process Methods 0.000 abstract 1
- 239000011148 porous material Substances 0.000 abstract 1
- 230000001737 promoting effect Effects 0.000 abstract 1
- 238000005057 refrigeration Methods 0.000 abstract 1
- 238000005065 mining Methods 0.000 description 5
- 238000010276 construction Methods 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 238000005422 blasting Methods 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000011010 flushing procedure Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000012425 Freezing-thawing process Methods 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 238000010257 thawing Methods 0.000 description 1
Classifications
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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
- E21B43/25—Methods for stimulating production
- E21B43/26—Methods for stimulating production by forming crevices or fractures
-
- 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
- E21B43/25—Methods for stimulating production
- E21B43/26—Methods for stimulating production by forming crevices or fractures
- E21B43/261—Separate steps of (1) cementing, plugging or consolidating and (2) fracturing or attacking the formation
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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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- 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)
- Filling Or Discharging Of Gas Storage Vessels (AREA)
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
- Pipe Accessories (AREA)
Abstract
An enhanced phase-change fracking gas extraction method for a low-permeability coal bed, comprising: injecting water at room temperature into a coal bed (1) through a drilling hole, and shutting off a valve after water injection is complete; freezing the coal bed around the water injection hole (2) using a refrigeration and freezing technique, the free water inside the coal bed fractures gradually transitioning from a liquid state to a solid state during the freezing process to expand and break the coal mass and promote generation and expansion of fractures inside the coal mass; after the freezing process is complete, the coal bed absorbs underground environmental heat and melts, further promoting coal mass pore interconnection and fracture expansion, and enhancing the effect of phase change fracking; after the melting process is complete, connecting the water injection hole to a gas extraction pipe and extracting gas, or drilling a gas extraction drilling hole in the coal bed in a phase-change fracking area and extracting gas. In the gas extraction process, phase-change fracking can be applied repeatedly to the drilling hole depending on gas extraction results, thus achieving objectives of improving coal bed permeability and efficiently extracting gas.
Description
Description
ENHANCED PHASE-CHANGE FRACKING GAS EXTRACTION METHOD FOR LOW-PERMEABILITY COAL BED
Field of the Invention
The present invention relates to a gas extraction method, particularly to a method for enhancing gas extraction from a coal seam with high gas concentration and low air permeability by hydraulic phase-transition fracturing.
Background of the Invention
Coal is a fundamental energy resource in China. As the mining depth is increased, gas has become a major factor that severely threatens safe production in coal mines. In 90% or more mines in China, the mining work is done by miners. In the mining process in mines with a high gas outburst risk or high coal and gas outburst risk, which account for 51 % or more in the mines in China, a large quantity of gas gushes. The threatening of gas explosion and gas outburst is more and more severe. Therefore, gas disaster has become a principal factor that constrains the development of efficient and intensive coal mining and safe production. In view that most coal seams in China belong to coal seam with high gas concentration and low air permeability, a major measure for solving the gas problem in the mining process of coal seams with high gas concentration and low air permeability is gas extraction from the coal seams in advance. With conventional gas extraction methods, the effective scope of influence is very small, the spacing between the drilled holes is 0.5 to 2m, the hole drilling work load at the working face is heavy, the extraction efficiency is low. In some mines, the extraction time is as long as one or more years, but the gas extraction result still does not meet the gas extraction standard in China. Hence, conventional gas extraction methods cannot attain an ideal effect of gas extraction for coal seams with high gas concentration and low air permeability. In order to meet the gas extraction standard and eliminate gas disasters in coal seams, permeability improvement measures must be taken, and the effective scope of influence per hole must be enlarged, so as to improve the gas extraction effect. At present, the pressure relief and air permeability improvement measures for coal seams with high gas concentration and low air permeability improve the air permeability of the coal seams by loosening the raw coal mass manually in advance, and mainly employ techniques including deep-hole loose blasting technique, water-jet cutting technique, hydraulic flushing technique, and hydraulic fracturing technique for downhole coal seam, etc. The deep-hole loose blasting technique, water-jet cutting technique, and hydraulic flushing technique have many problems, for example, the effective scope of influence per hole is small, the workload is heavy, and the construction process is complex, etc.. The conventional downhole hydraulic fracturing technique can realize a pressure relief in the coal seam at a large scope relatively. Owing to that the conventional downhole hydraulic fracturing technique employs high-pressure water injection at a high flow rate, the high-pressure water is influenced by stress distribution in the coal mass and the main fissure in the coal seam, and the fracture propagation direction can't be controlled, which results in that pressure relief is realized in some parts of the coal mass, and stress concentration occurs in other parts of the coal mass. Namely, high stress concentration areas in which the stress is as high as 3 to 4 times of the original stress exists while a pressure relief effect is attained. Hence, it is difficult to realize pressure relief and air permeability improvement across the entire area.
Contents of the Invention
Technical problem: The present invention provides a new method for enhancing gas extraction from a coal seam with high gas concentration and low air permeability, which utilizes the principle of water phase-transition, uses water injection technique and coal seam freezing technique in combination, and performs coal seam fracturing by means of water phase transition to form a complex fissure network in the coal mass and thereby increase gas flow channels in the coal seam.
Technical solution: The method for enhancing gas extraction from a low air-permeability coal 1 seam by hydraulic phase-transition fracturing provided in the present invention comprises the following steps: a. arranging phase-transition fracturing units along a down direction towards the coal seam in a roadway, each unit comprises a water injection hole, two freezing holes, and two temperature measuring holes, the procedures is as follows: first, constructing a water injection hole with a hole depth of 80 to 200m in the coal seam with a conventional technique; then, constructing freezing holes parallel to the water injection hole at a position at a distance L of 5 to 10m from the water injection hole at two sides of the water injection hole,respectively; constructing temperature measuring holes having a diameter of 75mm and a hole depth of 30m between each freezing hole and the water injection hole respectively, at a distance N of 3m from the water injection hole; b. running a high-pressure water injection pipe into the water injection hole, sealing the water injection hole with a capsule hole sealer, and then feeding a temperature sensor into the temperature measuring hole to a depth not smaller than 20m; next, sealing the temperature measuring hole by grout injection in a hole sealing section having a length not smaller than 12m; running freezing pipes into the two freezing hole respectively to a depth not smaller than 80% depth of the freezing hole, and then sealing the holes by grout injection; c. connecting the high-pressure water injection pipe to a high-pressure water-injection pump, injecting high-pressure water into the water injection hole through the high-pressure water injection pipe at 3 to 15MPa of water injection pressure, and stopping the water injection when a water seepage phenomenon occurs on the coal wall of the water injection hole, or the water injection pressure decreases suddenly, or continuously injecting water until the water injection pressure has no change persistently; d. connecting the freezing pipe in the freezing hole to an underground freezing system, and performing freezing phase-transition fracturing for the coal seam through the freezing pipe; in the phase-transition fracturing process, transmitting a temperature signal in coal seam to a digital temperature display device through a data wire by the temperature sensor in each temperature measuring hole, so as to monitor the coal seam temperature in the two temperature measuring holes in real time with the digital temperature display device; judging the coal seam in the phase-transition fracturing unit has been frozen when the coal seam temperature in the two temperature measuring holes reaches -3 °C; thus, coal seam is fractured by means of water phase transition, a complex fissure network is formed in the coal mass, and thereby gas flow channels are increased in the coal seam; e. shutting down the freezing system after phase transition fracturing, so that the frozen coal seam gradually absorbs heat from the downhole environment and start to thaw; judging that the water in the frozen coal seam within the scope of phase-transition fracturing has transformed from solid state to liquid state completely when the digital temperature display device indicates that the temperature in all temperature measuring holes is higher than 3°Q thus, the phase transition fracturing process in a unit is finished; f. connecting the water injection hole to a gas extraction pipeline, and performing gas extraction in the unit after phase-transition fracturing with a conventional technique; g. repeating the steps a, b, c, d, e and f to perform phase-transition fracturing and gas extraction in the next unit, and so on, till the phase-transition fracturing and gas extraction is finished in all units.
If the gas concentration or flow rate variation is abnormal in the gas extraction process in the phase-transition fracturing area, water injection and freezing can be repeated in the phase-transition fracturing unit to improve the air permeability in the coal seam in the phase-transition fracturing area, and thereby attain a gas extraction enhancing effect.
Beneficial effects: With the above-mentioned technical solution, the method provided in the present invention utilizes the principle of water phase transition, uses water injection technique and coal seam freezing technique in combination, and carries out coal seam fracturing by means of 2 water phase transition; thus, the coal mass is subjected to an expansion force in the freezing influence area, so that larger fissures in the coal seam propagate and interconnect with each other, and micro-porous fissures are formed and gradually developed, so as to form a regenerated fissure network, which provides gas flow channels in the coal seam, changes the mechanical properties of the coal mass, improves the air permeability in the high gas-containing coal seam, and improves the gas flow state in the coal seam. The radius of influence on gas extraction from the hole may be as large as 10 to 40m; thus, compared with ordinary gas extraction holes, the effective radius of influence on gas extraction per hole can be enlarged by 5 to 20 times, and the number of gas extraction holes can be decreased by 20% to 60%. In addition, secondary fissures are generated and developed continuously in the coal seam owing to hydraulic phase transition; thus, gas flow channels are effectively increased in the coal seam in the freezing area at macroscopic and microscopic levels, the air permeability coefficient of the coal seam can be increased by 30 to 200 times, the average volumetric gas extraction rate in a single hole can be 0.8m3/min., the gas concentration in gas extraction can be as high as 30 to 90%, and the gas extraction ratio at the working face is 50% or higher; in that way, the problems in gas extraction from coal seams with high gas content and low air permeability, such as low gas extraction efficiency, long extraction cycle, and small scope of influence of hole on extraction, etc. are solved. The method is simple, easy to operate, attains a good effect, is highly safe, has high applicability to coal seams, and thereby has extensive practicability in the art.
Description of the Drawings
Fig. 1 is a schematic diagram illustrating construction in horizontal direction at a working face according to the present invention;
Fig. 2 is a schematic diagram illustrating construction in vertical direction at working face along A-AofFig. 1;
Fig. 3 is a sectional view of the water injection hole connection system along B-B of Fig. 1;
Fig. 4 is a sectional view of the freezing hole connection system along C-C of Fig. 1;
Fig. 5 is a sectional view of the temperature measuring hole connection system along D-D of Fig. 1.
In the figures: 1 - coal seam; 2 - water injection hole; 3-1 - freezing hole; 3-2 - freezing hole; 4-1 -temperature measuring hole; 4-2 - temperature measuring hole; 5 - high-pressure water injection pipe; 6 - capsule hole sealer; 7 - temperature sensor; 8 - data wire; 9 - digital temperature display device; 10 - grouting and hole sealing section; 11 - freezing pipe; 12 - high-pressure water-injection pump; 13 - stop valve; 14 - freezing system.
Detailed Description of the Embodiments
Hereunder the present invention will be detailed in an embodiment with reference to the accompanying drawings.
The method for enhancing gas extraction from a low air-permeability coal seam by hydraulic phase-transition fracturing provided in the present invention comprises the following steps: a. arranging phase-transition fracturing units along a down direction towards the coal seam 1 in a roadway, each unit comprises a water injection hole 2, two freezing holes 3, and two temperature measuring holes 4., The procedures are as follows: first, constructing a water injection hole 2 having a diameter of 75 to 130mm and a hole depth of 80 to 200m towards the coal seam 1 with a conventional technique; then, constructing freezing holes 3 parallel to the water injection hole 2 at a position at a distance L of 5 to 10m from the water injection hole 2 at two sides of the water injection hole 2 respectively, constructing temperature measuring holes 4 having a diameter of 75mm and a hole depth of 30m between each freezing hole 3 and the water injection hole 2 respectively, at a distance N of 3m from the water injection hole 2; b. running a high-pressure water injection pipe 5 into the water injection hole 2, sealing the water injection hole 2 with a capsule hole sealer 6 used in the conventional technique, and 3 then feeding a temperature sensor 7 into the temperature measuring hole 4 to a depth not smaller than 20m; next, sealing the temperature measuring hole 4 by grout injection in a hole sealing section 10 having a length not smaller than 12m; running freezing pipes 11 into the two freezing holes 3 respectively to a depth not smaller than 80% depth of the freezing hole 3, and then sealing the holes by grout injection; c. connecting the high-pressure water injection pipe 5 to a high-pressure water-injection pump 12, injecting high-pressure water into the water injection hole 2 through the high-pressure water injection pipe 5 at 3 to 15MPa of water injection pressure, so that water at normal temperature is injected into the coal seam through the hole 2; and closing the stop valve 13 at the hole orifice of the water injection hole 2 when a water seepage phenomenon occurs on the coal wall of the water injection hole 2, or the water injection pressure decreases suddenly, or continuously injecting water until the water injection pressure has no change persistently; after the water injection is stopped, the injected water remains in the coal seam and persistently seeps into smaller fissures; d. connecting the freezing pipe 11 in the freezing hole 3 to a downhole freezing system 14, freezing the water injected into the hole in the coal seam and around the hole with a freezing technique, so that the free water in the fractures in the coal seam gradually transforms from liquid state to solid state and has phase change in the freezing process; in the phase transition process, the volume of water expands and increases by about 9.1%, causing expansion damage to the coal mass and thereby prompting the generation and propagation of fissures in the coal mass; performing phase-transition fracturing for the coal seam 1 through the freezing pipe 11; in the phase-transition fracturing process, transmitting a temperature signal in coal seam 1 to a digital temperature display device 9 through a data wire 8 by the temperature sensor 7 in each temperature measuring hole 4, so as to monitor the coal seam temperature in the two temperature measuring holes 4 in real time with the digital temperature display device 9; judging the coal seam in the phase-transition fracturing unit has been frozen when the coal seam temperature in the two temperature measuring holes 4 reaches -3°C; e. shutting down the freezing system 14 after the phase-transition fracturing, so that the frozen coal seam 1 gradually absorbs heat from the downhole environment and starts to thaw; in the thawing process, the fissures in the coal mass further interconnect with each other and propagate, and thereby the phase-transition fracturing effect is enhanced; it is believed that the water in the coal seam 1 within the scope of phase-transition fracturing has transformed from solid state to liquid state completely when the digital temperature display device 9 indicates that the temperature in the two temperature measuring holes 4 is higher than 3°Q thus, the phase-transition fracturing process in a unit is finished; f. after the freezing-thawing process is finished, connecting the high-pressure water injection pipeline in the water injection hole 2 to a gas extraction pipeline, and performing gas extraction in the phase-transition fracturing unit with a conventional technique; or, constructing a plurality of gas extraction holes in the coal seam 1 in the area of influence of phase-transition fracturing for gas extraction, so as to improve the gas extraction efficiency; if the gas concentration or flow rate variation is abnormal in the gas extraction process in the phase-transition fracturing area, water injection and freezing can be repeated in the phase-transition fracturing unit to improve the air permeability in the coal seam in the phase-transition fracturing area, and thereby to attain a gas extraction enhancing effect; such abnormalities include: the gas flow rate or concentration is decreased suddenly, or the flow rate is attenuated to a low level (<0.005m3/min.) in a short period (<10 days); g. repeating the steps a, b, c, d, e and f to perform phase-transition fracturing and gas extraction in the next unit, and so on, till the phase-transition fracturing and gas extraction is finished in all units. 4
Claims (2)
- _Claims_1. A method for enhancing gas extraction from a low air-permeability coal seam by hydraulic phase-transition fracturing, wherein said method comprises the following steps: a. arranging phase-transition fracturing units along a down direction towards the coal seam (1) in a roadway, each unit comprises a water injection hole (2), two freezing holes (3), and two temperature measuring holes (4), the procedures are as follows: first, constructing a water injection hole (2) having a hole depth of 80~200m towards the coal seam (1) with a conventional technique; then, constructing freezing holes (3) parallel to the water injection hole (2) at a position at a distance L of 5~10m from the water injection hole (2) at two sides of the water injection hole (2) respectively, constructing temperature measuring holes (4) having a diameter of 75mm and a hole depth of 30m between each freezing hole (3) and the water injection hole (2) respectively, at a distance N of 3m from the water injection hole (2); b. running a high-pressure water injection pipe (5) into the water injection hole (2), sealing the water injection hole (2) with a capsule hole sealer (6), and then feeding a temperature sensor (7) into the temperature measuring hole (4) to a depth not smaller than 20m; next, sealing the temperature measuring hole (4) by grout injection in a hole sealing section (10) having a length not smaller than 12m; running freezing pipes (11) into the two freezing holes (3) respectively to a depth not smaller than 80% depth of the freezing hole (3), and then sealing the hole by grout injection; c. connecting the high-pressure water injection pipe (5) to a high-pressure water-injection pump (12), injecting high-pressure water into the water injection hole (2) through the high-pressure water injection pipe (5) at 3 to 15MPa of water injection pressure, and stopping the water injection when a water seepage phenomenon occurs on the coal wall of the water injection hole (2), or the water injection pressure decreases suddenly, or continuously injecting water until the water injection pressure has no change persistently; d. connecting the freezing pipe (11) in the freezing hole (3) to an underground freezing system (14), and performing phase-transition fracturing for the coal seam (1) through the freezing pipe (11); in the phase-transition fracturing process, transmitting a temperature signal in coal seam (1) to a digital temperature display device (9) through a data wire (8) by the temperature sensor (7) in each temperature measuring hole (4), so as to monitor the coal seam temperature in the two temperature measuring holes (4) in real time with the digital temperature display device (9); judging the coal seam in the phase-transition fracturing unit has been frozen when the coal seam temperature in the two temperature measuring holes (4) reaches -3°Q e. shutting down the freezing system (14) after phase transition fracturing, so that the frozen coal seam (1) gradually absorbs heat from the downhole environment and starts to thaw; judging that the water in the frozen coal seam (1) within the scope of phase-transition fracturing has transformed from solid state to liquid state completely when the digital temperature display device (9) indicates that the temperature in the temperature measuring holes (4) is higher than 3°Q thus, the phase transition fracturing process in a unit is finished; f. connecting the water injection hole (2) to a gas extraction pipeline, and performing gas extraction in the unit after phase-transition fracturing with a conventional technique; g. repeating the steps a, b, c, d, e and f to perform phase-transition fracturing and gas extraction in the next unit, and so on, till the phase-transition fracturing and gas extraction is finished in all units.
- 2. The method for enhancing gas extraction from a low air-permeability coal seam by hydraulic phase-transition fracturing according to claim 1, wherein, if the gas concentration or flow rate variation is abnormal in the gas extraction process in the phase-transition fracturing area, water injection and freezing can be repeated in the phase-transition fracturing unit to improve the air permeability in the coal seam in the phase-transition fracturing area, and thereby to attain a gas extraction enhancing effect.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
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CN201410386481.4 | 2014-08-07 | ||
CN201410386481.4A CN104265354B (en) | 2014-08-07 | 2014-08-07 | A kind of low air permeability coal seam waterpower phase transformation fracturing strengthening gas pumping method |
PCT/CN2015/085652 WO2016019825A1 (en) | 2014-08-07 | 2015-07-31 | Enhanced phase-change fracking gas extraction method for low-permeability coal bed |
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AU2015299587B2 AU2015299587B2 (en) | 2018-03-01 |
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AU (1) | AU2015299587B2 (en) |
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CN101915085B (en) * | 2010-08-13 | 2011-09-28 | 山西晋城无烟煤矿业集团有限责任公司 | Low-air-permeability coal-bed gas extraction method |
CN102155254B (en) * | 2011-02-28 | 2013-05-22 | 中国矿业大学 | Method for extracting gas in low air permeability coal layer by pulse fracture anti-reflection |
RU2012121635A (en) * | 2012-05-25 | 2013-11-27 | Общество с ограниченной ответственностью "Газпром добыча Кузнецк" | METHOD FOR EXTRACTION OF METHANE FROM COAL LAYER |
RU2511329C1 (en) * | 2012-11-02 | 2014-04-10 | Федеральное государственное бюджетное учреждение науки ИНСТИТУТ ПРОБЛЕМ КОМПЛЕКСНОГО ОСВОЕНИЯ НЕДР РОССИЙСКОЙ АКАДЕМИИ НАУК (ИПКОН РАН) | Method of action on coal bed |
CN104265354B (en) * | 2014-08-07 | 2016-04-20 | 中国矿业大学 | A kind of low air permeability coal seam waterpower phase transformation fracturing strengthening gas pumping method |
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2014
- 2014-08-07 CN CN201410386481.4A patent/CN104265354B/en active Active
-
2015
- 2015-07-31 AU AU2015299587A patent/AU2015299587B2/en not_active Ceased
- 2015-07-31 WO PCT/CN2015/085652 patent/WO2016019825A1/en active Application Filing
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WO2016019825A1 (en) | 2016-02-11 |
AU2015299587B2 (en) | 2018-03-01 |
CN104265354B (en) | 2016-04-20 |
CN104265354A (en) | 2015-01-07 |
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