CN115492563A - Multi-drill-hole through type fracturing, punching, permeation increasing and pressure relieving device and method for soft coal seam - Google Patents
Multi-drill-hole through type fracturing, punching, permeation increasing and pressure relieving device and method for soft coal seam Download PDFInfo
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- CN115492563A CN115492563A CN202211184025.2A CN202211184025A CN115492563A CN 115492563 A CN115492563 A CN 115492563A CN 202211184025 A CN202211184025 A CN 202211184025A CN 115492563 A CN115492563 A CN 115492563A
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- 239000003245 coal Substances 0.000 title claims abstract description 181
- 238000004080 punching Methods 0.000 title claims abstract description 29
- 238000000034 method Methods 0.000 title claims abstract description 13
- 230000035699 permeability Effects 0.000 claims abstract description 26
- 238000000605 extraction Methods 0.000 claims abstract description 22
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 20
- 239000010959 steel Substances 0.000 claims abstract description 20
- 239000011083 cement mortar Substances 0.000 claims abstract description 9
- 239000003818 cinder Substances 0.000 claims abstract description 8
- 238000000926 separation method Methods 0.000 claims abstract description 5
- 238000005553 drilling Methods 0.000 claims description 2
- 230000035515 penetration Effects 0.000 claims 2
- 238000005336 cracking Methods 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 6
- 238000007599 discharging Methods 0.000 description 9
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 239000002893 slag Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
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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
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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)
- Rigid Pipes And Flexible Pipes (AREA)
Abstract
The invention belongs to the technical field of coal mine underground hydraulic permeation increase, and relates to a soft coal seam multi-drill hole through type fracturing punching permeation increase pressure relief device and a method, wherein the device comprises a coal layer fracturing hole and a plurality of coal unloading holes arranged around the coal layer fracturing hole, the fracturing hole and the coal unloading holes are sealed by cement mortar, and are sealed to coal points, wherein the coal unloading holes are wrapped by the cement mortar to form large-diameter coal unloading steel pipes, and orifices of the large-diameter coal unloading steel pipes are connected with orifice devices; the method can effectively realize large-range permeability increase through fracturing, can realize linkage permeability increase and pressure relief through coal unloading hole punching pressure relief, has strong operability and easy implementation, and solves the problem of poor permeability increase and pressure relief effect of a single hydraulic measure; meanwhile, the orifice device of the coal unloading hole can realize pressure maintaining by closing the gate valve, the orifice device of the coal unloading hole can realize coal and water separation, coal cinder is stored in the coal storage box, and orifice gas is pumped into the low-negative-pressure extraction system, so that the gas overrun caused in the fracturing and punching process is prevented.
Description
Technical Field
The invention belongs to the technical field of underground coal mine hydraulic permeability increasing, and relates to a soft coal seam multi-drill-hole through type fracturing, punching, permeability increasing and pressure relieving device and method.
Background
Hydraulic fracturing destroys coal bodies through water pressure to form a fracture network, is applied to the aspect of coal seam permeability increasing, but the fracturing effect is different. The fracturing is particularly carried out in soft coal, the soft coal has low firmness coefficient, obvious plastic characteristic and low strength, and has lower air permeability than hard coal, and fractures develop and are not communicated. The soft coal is mainly characterized by plastic deformation, crack initiation and permeability increasing rules of the soft coal have obvious difference, and how to simply use hydraulic fracturing effect under the soft coal condition is difficult to guarantee.
The traditional hydraulic punching is more applied in the soft coal permeability increasing engineering practice, and has the defects of small permeability increasing range, and low efficiency because water flow peels off coal bodies through the cavity inside the drill hole.
Disclosure of Invention
In view of the above, the invention aims to provide a multi-drill hole through type fracturing punching permeability increasing and pressure relieving device and method for a soft coal seam, so that high-pressure water can flow out from the inside of a coal body to a drill hole cavity, and the coal stripping efficiency is higher.
In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a many drilling through type fracturing of soft coal seam punches a hole and increases and oozes pressure relief device, includes coal layer fracture hole to and set up a plurality of coal discharge holes around coal layer fracture hole, fracturing hole and coal discharge hole all adopt cement mortar hole sealing, and the hole sealing sees the coal point, and wherein coal discharge hole has major diameter coal discharge steel pipe with cement mortar parcel, and the drill way of major diameter coal discharge steel pipe is connected with the drill way device.
Optionally, the orifice device comprises an orifice tee connected with the large-diameter coal unloading steel pipe, and a coal storage tank and a low negative pressure extraction pipeline which are respectively communicated with the orifice tee.
Optionally, the orifice tee is connected with the large-diameter coal unloading steel pipe through an orifice gate valve, and a low-negative-pressure extraction pipe gate valve is further arranged between the low-negative-pressure extraction pipeline and the orifice tee.
Optionally, a filter screen is further arranged at the joint of the low negative pressure extraction pipeline and the orifice tee.
Optionally, the side face of the coal storage box is provided with a hollow skeleton structure, and a fine mesh steel wire mesh is wrapped, so that coal and water separation is effectively realized.
Optionally, a sensor is arranged in the coal storage tank, and the sensor is connected with a coal cinder information display board arranged on the coal storage tank and used for measuring the quality and humidity of coal cinder in the metering tank.
Optionally, the diameter phi of the large-diameter coal unloading steel pipe is greater than 60mm.
The method for increasing permeability and relieving pressure of the soft coal seam multi-drill hole through type fracturing punching is applied to the soft coal seam multi-drill hole through type fracturing punching permeability and pressure increasing device and comprises the following steps:
s1, injecting water into coal bed coal through a fracturing hole, carrying out fracturing in a region between the fracturing hole and a coal unloading hole, and allowing coal and gas to burst out of the coal unloading hole to enter an orifice device of the coal unloading hole when a crack penetrates through the coal unloading hole;
s2, opening a gate valve of a low-negative-pressure extraction pipe, enabling gas to enter a low-negative-pressure extraction pipeline, enabling coal to enter a coal storage box through a hose at the bottom of an orifice tee joint, forming a U-shaped channel in a fracturing hole and a coal unloading hole, and injecting water through the fracturing hole to realize punching and coal unloading of the coal unloading hole;
and S3, after the designed coal unloading amount is reached, closing the orifice gate valve of the coal unloading hole, continuing fracturing, after the pressure is suppressed, driving the high-pressure water to other coal unloading holes, and after the high-pressure water penetrates through other coal unloading holes, repeating the operation until the coal unloading of the coal unloading holes nearby the fracturing hole is finished.
Optionally, the orifice gate valve is in an open state at the beginning of fracturing, and the bottom outlet of the tee is connected with the coal storage tank through a hose.
The invention has the beneficial effects that: the soft coal seam multi-drill hole through type fracturing punching permeability increasing and pressure relieving device and method can effectively realize large-range permeability increasing through fracturing, can realize linkage permeability increasing and pressure relieving through coal unloading hole punching pressure relief, have strong operability and are easy to implement, and solve the problem of poor permeability increasing and pressure relieving effect of a single hydraulic measure; meanwhile, the orifice device of the coal unloading hole can realize pressure maintaining by closing the gate valve, the orifice device of the coal unloading hole can realize coal and water separation, coal cinder is stored in the coal storage box, and orifice gas is pumped into the low-negative-pressure extraction system, so that the gas overrun caused in the fracturing and punching process is prevented.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims thereof.
Drawings
For the purposes of promoting a better understanding of the objects, aspects and advantages of the invention, reference will now be made to the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic view of the operation of a first coal discharge hole of the present invention;
FIG. 2 is a schematic view of the arrangement of fracturing holes and coal discharge holes of the present invention.
Reference numerals are as follows: the device comprises a fracturing hole 1, a first coal unloading hole 2, a second coal unloading hole 3, a third coal unloading hole 4, a fourth coal unloading hole 5, a large-diameter coal unloading steel pipe 6, cement mortar 7, an orifice gate valve 8, an orifice tee joint 9, a low-negative-pressure extraction pipe gate valve 10, a low-negative-pressure extraction pipeline 11, a coal cinder information display board 12, a coal storage box 13 and a hollow framework 14.
Detailed Description
The following embodiments of the present invention are provided by way of specific examples, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention in a schematic way, and the features in the following embodiments and embodiments may be combined with each other without conflict.
Wherein the showings are for the purpose of illustrating the invention only and not for the purpose of limiting the same, and in which there is shown by way of illustration only and not in the drawings in which there is no intention to limit the invention thereto; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", etc., based on the orientation or positional relationship shown in the drawings, it is only for convenience of description and simplification of description, but it is not an indication or suggestion that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes, and are not to be construed as limiting the present invention, and the specific meaning of the terms may be understood by those skilled in the art according to specific situations.
Referring to fig. 1-2, the device comprises a coal seam fracturing hole 1 and a plurality of coal unloading holes arranged around the coal seam fracturing hole 1, wherein the fracturing hole 1 and the coal unloading holes are sealed by cement mortar 7 and are sealed to coal-visible points, the coal unloading holes are wrapped by the cement mortar 7 and are provided with a large-diameter coal unloading steel pipe 6, an orifice of the large-diameter coal unloading steel pipe 6 is connected with an orifice device, the orifice device comprises an orifice tee 9 connected with the large-diameter coal unloading steel pipe 6, a coal storage box 13 and a low-negative-pressure extraction pipeline 11 which are respectively communicated with the orifice tee 9, the orifice tee 9 is connected with the large-diameter coal unloading phi steel pipe 6 through an orifice gate valve 8, a low-negative-pressure extraction pipe gate valve 10 is arranged between the low-negative-pressure extraction pipeline 11 and the orifice tee 9, a filter screen is further arranged at the connection of the low-negative-pressure extraction pipeline 11 and the orifice tee 9, a hollow framework 14 structure is arranged on the side of the coal storage box 13, a fine-eye steel wire mesh is wrapped, coal and a coal storage box 13 is provided with a coal storage box sensor, the coal storage box 13 is connected with a coal moisture meter and a coal-slag discharge pipe, and is used for moisture and water separation, and the coal-moisture meter box is used for displaying the coal moisture and the coal-slag in the coal-moisture content of the coal-moisture meter 60mm and the coal-moisture meter.
In this embodiment, there are 4 coal discharging holes, which are the first coal discharging hole 2, the second coal discharging hole 3, the third coal discharging hole 4 and the fourth coal discharging hole 5, and this embodiment is illustrated by the working state of the first coal discharging hole 2 alone.
The method for increasing permeability and relieving pressure of the soft coal seam multi-drill hole through type fracturing punching is applied to the soft coal seam multi-drill hole through type fracturing punching permeability and pressure increasing device and comprises the following steps:
s1, injecting water into coal bed coal through a fracturing hole 1, carrying out fracturing in a region between the fracturing hole 1 and a coal unloading hole, and allowing coal and gas to burst out of the coal unloading hole and enter an orifice device of the coal unloading hole when a crack penetrates through the coal unloading hole;
s2, opening a gate valve 10 of a low-negative-pressure extraction pipe, enabling gas to enter a low-negative-pressure extraction pipeline 11, enabling coal to enter a coal storage box 13 through a hose at the bottom of an orifice tee 9, forming a U-shaped channel between the fracturing hole 1 and a coal unloading hole, and injecting water through the fracturing hole 1 to realize punching and coal unloading of the coal unloading hole;
and S3, after the designed coal unloading amount is reached, closing the orifice gate valve 8 of the coal unloading hole, continuing fracturing, after the pressure is suppressed, driving the high-pressure water to other coal unloading holes, and after the high-pressure water penetrates through other coal unloading holes, repeating the operation until the coal unloading holes near the fracturing hole 1 are all used for unloading coal, and finishing the operation.
In this embodiment, the orifice gate valve 8 is in an open state at the start of fracturing.
The invention enables high-pressure water to gush out from the inside of the coal body to the cavity of the drill hole, thus the efficiency of coal stripping is higher; in addition, by optimizing the arrangement of the fracturing holes 1 and the punching and coal discharging holes, on one hand, the seepage increasing of a large-range hydraulic fracturing area can be realized, and on the other hand, the seepage increasing and pressure discharging linkage effect is formed by hydraulic punching and coal discharging in a small radial range of a drill hole.
Finally, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (9)
1. The utility model provides a many drilling through fracturing of soft coal seam are punched a hole and are increased and ooze pressure relief device which characterized in that: the coal pressure cracking hole and the coal unloading holes are sealed by cement mortar and the coal points are sealed, wherein the coal unloading holes are wrapped by the cement mortar and are provided with large-diameter coal unloading steel pipes, and the orifices of the large-diameter coal unloading steel pipes are connected with orifice devices.
2. The soft coal seam multi-drill hole through type fracturing, punching, permeability increasing and pressure relieving device of claim 1, which is characterized in that: the orifice device comprises an orifice tee joint connected with the large-diameter coal unloading steel pipe, and a coal storage tank and a low-negative-pressure extraction pipeline which are respectively communicated with the orifice tee joint.
3. The soft coal seam multi-drill hole through type fracturing, punching, permeability increasing and pressure relieving device of claim 2, which is characterized in that: the orifice tee joint is connected with the large-diameter coal unloading steel pipe through the orifice gate valve, and a low negative pressure extraction pipe gate valve is arranged between the low negative pressure extraction pipeline and the orifice tee joint.
4. The soft coal seam multi-drill hole through type fracturing, punching, permeability increasing and pressure relieving device according to claim 3, characterized in that: and a filter screen is arranged at the joint of the low negative pressure extraction pipeline and the orifice tee.
5. The soft coal seam multi-drill hole through type fracturing punching permeability-increasing pressure-relief device of claim 2, wherein: the side face of the coal storage box is provided with a hollow skeleton structure, and a fine mesh steel wire mesh is wrapped, so that coal and water separation is effectively realized.
6. The soft coal seam multi-drill-hole through type fracturing punching permeability-increasing pressure-relief device according to claim 5, characterized in that: a sensor is arranged in the coal storage tank and connected with a coal cinder information display board arranged on the coal storage tank, and the sensor is used for measuring the coal cinder quality and the coal cinder humidity in the metering tank.
7. The soft coal seam multi-drill hole through type fracturing punching permeability-increasing pressure-relief device of claim 1, characterized in that: the diameter phi of the large-diameter coal unloading steel pipe is more than 60mm.
8. A penetration type fracturing, punching, permeability increasing and pressure relieving method for multiple drill holes of a soft coal seam is applied to the penetration type fracturing, punching, permeability increasing and pressure relieving device for multiple drill holes of a soft coal seam according to any one of claims 1 to 7, and is characterized by comprising the following steps:
s1, injecting water into coal bed coal through a fracturing hole, carrying out fracturing in a region between the fracturing hole and a coal unloading hole, and allowing coal and gas to burst out of the coal unloading hole to enter an orifice device of the coal unloading hole when a crack penetrates through the coal unloading hole;
s2, opening a gate valve of a low-negative-pressure extraction pipe, enabling gas to enter a low-negative-pressure extraction pipeline, enabling coal to enter a coal storage box through a hose at the bottom of an orifice tee joint, forming a U-shaped channel in a fracturing hole and a coal unloading hole, and injecting water through the fracturing hole to realize punching and coal unloading of the coal unloading hole;
and S3, after the designed coal unloading amount is reached, closing the orifice gate valve of the coal unloading hole, continuing fracturing, after the pressure is suppressed, driving the high-pressure water to other coal unloading holes, and after the high-pressure water penetrates through other coal unloading holes, repeating the operation until the coal unloading of the coal unloading holes nearby the fracturing hole is finished.
9. The soft coal seam multi-drill hole through type fracturing punching permeability increasing and pressure relieving method according to claim 8, characterized in that: the orifice gate valve is in an open state at the start of fracturing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211184025.2A CN115492563A (en) | 2022-09-27 | 2022-09-27 | Multi-drill-hole through type fracturing, punching, permeation increasing and pressure relieving device and method for soft coal seam |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211184025.2A CN115492563A (en) | 2022-09-27 | 2022-09-27 | Multi-drill-hole through type fracturing, punching, permeation increasing and pressure relieving device and method for soft coal seam |
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| CN115492563A true CN115492563A (en) | 2022-12-20 |
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| CN202211184025.2A Pending CN115492563A (en) | 2022-09-27 | 2022-09-27 | Multi-drill-hole through type fracturing, punching, permeation increasing and pressure relieving device and method for soft coal seam |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102720528A (en) * | 2012-07-03 | 2012-10-10 | 中国矿业大学 | Underground coal mine repeating pulsation hydrofracture strengthened gas extracting method |
| CN103362538A (en) * | 2013-07-15 | 2013-10-23 | 中国矿业大学 | Coal seam cutting, fracturing, pressure pumping and alternating gas extraction method |
| CN103912302A (en) * | 2014-01-26 | 2014-07-09 | 中国矿业大学 | Seam-penetrating drilling hydrofracturing gas extracting method |
| CN104863628A (en) * | 2015-04-15 | 2015-08-26 | 中国矿业大学 | Method for fracturing and permeability improvement to shield coal road excavation by utilizing pulse detonation waves |
| CN106285599A (en) * | 2016-08-05 | 2017-01-04 | 河南能源化工集团研究院有限公司 | A kind of waterpower changing of the relative positions release anti-reflection draining coal seam gas method |
| WO2017075935A1 (en) * | 2015-11-06 | 2017-05-11 | 中国矿业大学 | Method of increasing permeability of coal seam using high-power electric blasting assisted by hydraulic fracturing from bottom drainage roadway |
| WO2017092207A1 (en) * | 2015-11-30 | 2017-06-08 | 中国矿业大学 | Method of performing combined drilling, flushing, and cutting operations on coal seam having high gas content and prone to bursts to relieve pressure and increase permeability |
| CN106930746A (en) * | 2017-03-06 | 2017-07-07 | 中国矿业大学 | The alternative expression coal seam anti-reflection method that drilling acetone invasion and attack are combined with hydraulic fracturing |
-
2022
- 2022-09-27 CN CN202211184025.2A patent/CN115492563A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102720528A (en) * | 2012-07-03 | 2012-10-10 | 中国矿业大学 | Underground coal mine repeating pulsation hydrofracture strengthened gas extracting method |
| CN103362538A (en) * | 2013-07-15 | 2013-10-23 | 中国矿业大学 | Coal seam cutting, fracturing, pressure pumping and alternating gas extraction method |
| CN103912302A (en) * | 2014-01-26 | 2014-07-09 | 中国矿业大学 | Seam-penetrating drilling hydrofracturing gas extracting method |
| CN104863628A (en) * | 2015-04-15 | 2015-08-26 | 中国矿业大学 | Method for fracturing and permeability improvement to shield coal road excavation by utilizing pulse detonation waves |
| WO2017075935A1 (en) * | 2015-11-06 | 2017-05-11 | 中国矿业大学 | Method of increasing permeability of coal seam using high-power electric blasting assisted by hydraulic fracturing from bottom drainage roadway |
| WO2017092207A1 (en) * | 2015-11-30 | 2017-06-08 | 中国矿业大学 | Method of performing combined drilling, flushing, and cutting operations on coal seam having high gas content and prone to bursts to relieve pressure and increase permeability |
| CN106285599A (en) * | 2016-08-05 | 2017-01-04 | 河南能源化工集团研究院有限公司 | A kind of waterpower changing of the relative positions release anti-reflection draining coal seam gas method |
| CN106930746A (en) * | 2017-03-06 | 2017-07-07 | 中国矿业大学 | The alternative expression coal seam anti-reflection method that drilling acetone invasion and attack are combined with hydraulic fracturing |
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