CN113818878A - Hydraulic fracturing rock breaking method and system - Google Patents
Hydraulic fracturing rock breaking method and system Download PDFInfo
- Publication number
- CN113818878A CN113818878A CN202111266773.0A CN202111266773A CN113818878A CN 113818878 A CN113818878 A CN 113818878A CN 202111266773 A CN202111266773 A CN 202111266773A CN 113818878 A CN113818878 A CN 113818878A
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- 239000011435 rock Substances 0.000 title claims abstract description 64
- 238000000034 method Methods 0.000 title claims abstract description 25
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 88
- 238000007789 sealing Methods 0.000 claims abstract description 16
- 229910003460 diamond Inorganic materials 0.000 claims description 11
- 239000010432 diamond Substances 0.000 claims description 11
- 238000005553 drilling Methods 0.000 claims description 11
- 238000003860 storage Methods 0.000 claims description 9
- 230000008569 process Effects 0.000 abstract description 9
- 239000000428 dust Substances 0.000 abstract description 4
- 238000003912 environmental pollution Methods 0.000 abstract 1
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical group O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 8
- 238000005422 blasting Methods 0.000 description 8
- 239000003795 chemical substances by application Substances 0.000 description 7
- 229910002092 carbon dioxide Inorganic materials 0.000 description 4
- 239000001569 carbon dioxide Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000002360 explosive Substances 0.000 description 4
- 238000005520 cutting process Methods 0.000 description 3
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 238000005507 spraying Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000005065 mining Methods 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000010009 beating Methods 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000012634 fragment Substances 0.000 description 1
- 230000003116 impacting effect Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000000053 physical method Methods 0.000 description 1
- 239000008400 supply water Substances 0.000 description 1
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Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C37/00—Other methods or devices for dislodging with or without loading
- E21C37/06—Other methods or devices for dislodging with or without loading by making use of hydraulic or pneumatic pressure in a borehole
- E21C37/12—Other methods or devices for dislodging with or without loading by making use of hydraulic or pneumatic pressure in a borehole by injecting into the borehole a liquid, either initially at high pressure or subsequently subjected to high pressure, e.g. by pulses, by explosive cartridges acting on the liquid
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
- Earth Drilling (AREA)
Abstract
The invention discloses a hydraulic fracturing rock-breaking method, which is characterized in that a plurality of holes are punched in advance at the position of rock to be broken in a mine, water is pressurized by utilizing a pressurizing device to obtain high-pressure water, an outlet of the pressurizing device is communicated into the holes through a high-pressure pipe, a sealing device is arranged at the joint of the high-pressure pipe and the holes, the high-pressure water is injected into the holes, the water pressure of the high-pressure water is continuously increased until the pressure in the holes exceeds the highest crack extension pressure of a rock mass, and the rock mass is broken. Therefore, the hydraulic fracturing rock breaking method has no dust and vibration in the rock breaking process, and does not produce environmental pollution. The invention also discloses a hydraulic fracturing rock breaking system.
Description
Technical Field
The invention relates to the field of mine rock breaking, in particular to a hydraulic fracturing rock breaking method and a hydraulic fracturing rock breaking system.
Background
In the mining process of mine rocks, the rocks need to be crushed and stripped, the current common method adopts explosive blasting, however, the blasting mode has the problems of difficult control of the explosive amount, misfire and the like, and the process has the safety and environmental protection problems of vibration, flyrock, dust, noise and the like, and the explosive blasting cannot control the crushing direction of the rocks.
With the enhancement of management and control and limitation of use of blast mining, a technique of rock crushing using a physical method is widely used. The common physical blasting mode is carbon dioxide gas breakage, hydraulic pressure splitting breakage, expanding agent splitting breakage, physical cutting breakage, water jet cutting breakage and the like, but the physical blasting mode is a small-volume breaking mode except for carbon dioxide gas breakage, the operation efficiency is low, and the operation cost is generally high. And the carbon dioxide gas is broken, and because the blasting mechanism is that the ore is broken by the gas impact force generated by instantly gasifying the carbon dioxide through high-temperature breakdown of the safety film, more safety risks also exist. Moreover, the operations of filling, connecting lines, sealing holes and the like are complicated, and errors are easy to occur, so the operation efficiency is not high; the expansion rock breaking technology can effectively control the blasting range, and the rock body is fractured and broken through the continuous expansion of the expanding agent, but the method needs a large amount of expanding agent, the cost is high, the used expanding agent has the problem of treatment, secondly, because the rock is fractured through the expansion of the expanding agent, the deformation of the expanding agent is limited, the expected expansion effect can not be achieved, and the reaction of the expanding agent generally needs several hours, and the efficiency is low. Similarly, the hydraulic splitting machine has the problems of low efficiency, serious equipment abrasion and the like, and the limitation of explosive blasting technology is more obvious when the rock body cracking direction needs to be controlled under special conditions. Therefore, a novel safe and environment-friendly rock breaking mode is very necessary.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: a hydraulic fracturing rock breaking method is provided.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
a hydraulic fracturing rock breaking method includes pre-drilling a plurality of holes at the position to be broken in a mine, utilizing a pressurizing device to supply water and pressurize to obtain high-pressure water, enabling an outlet of the pressurizing device to be communicated into the holes through a high-pressure pipe, arranging a sealing device at the joint of the high-pressure pipe and the holes, injecting the high-pressure water into the holes, and continuously increasing the water pressure of the high-pressure water until the pressure in the holes exceeds the crack extension pressure of a rock body, so that the rock body is broken.
On the basis of the technical scheme, the invention can be further improved as follows.
Preferably, the perforation holes are formed by impacting water flow jetted by the water jet;
preferably, the volume and direction of fracture of the rock mass are controlled by controlling the number of perforations, perforations.
Compared with the prior art, the invention has the following technical effects:
the invention provides a novel rock crushing method, which comprises the steps of pressurizing water by using a fracturing device, conveying the water to an eyelet drilled in a rock body through a high-pressure pipeline, sealing the eyelet by using a sealing device, completing directional perforation in the eyelet through a perforating device, namely perforation, gradually increasing the pressure in the eyelet along with the continuous injection of high-pressure water, and continuously expanding internal cracks of the rock until the rock body is crushed/stripped in a large volume after the pressure in the eyelet, particularly a perforated area exceeds the crack extension pressure of the rock. By controlling the depth, the number and the layout of the drilling holes and the perforation holes, the crushing volume and the direction of the rock body can be effectively controlled. Violent vibration, dust and the like are avoided in the rock breaking process, and the breaking direction is controllable.
A hydraulic fracturing rock breaking system comprises a water storage device, a pressurizing device and an actuator which are sequentially connected through a water pipe, wherein the water storage device is used for storing water, and the pressurizing device is used for pressurizing the water to obtain high-pressure water;
the head of the actuator is a drill bit, and the drill bit is used for forming holes in a rock body and can be a diamond bit, a roller bit, a drag bit and the like; a water flow passage communicated with a high-pressure water outlet of the pressurizing device is arranged in the actuator, a plurality of water knives communicated with the water flow passage are arranged on the outer wall of the middle part of the actuator, and the water knives are used for directionally spraying high-pressure water flow on a rock body to obtain a perforation; and a sealing element is arranged at the tail part of the actuator and used for sealing a gap between the tail part of the actuator and the inner wall of the hole.
Further, the pressurizing device is a plunger pump;
furthermore, each water jet cutter is provided with an independent control device which can independently control the opening and closing of the water jet cutter;
further, the number of the actuators is several.
Compared with the prior art, the scheme has the following beneficial effects:
1. the crushing volume and direction of the rock body can be effectively controlled by controlling the layout position and the number of the drilling holes and the perforating holes.
2. The water is pressurized by the plunger pump, hydraulic pressurization crushing of the rock mass is effectively completed, safe and environment-friendly crushing of the rock mass is realized, and vibration, flying stones, dust and noise cannot be generated in the process.
3. The plunger pumps and the multifunctional drilling machine are freely matched according to the number of the plunger pumps and the multifunctional drilling machine, and the requirements of the whole equipment scheme under different working conditions and different square quantities are met.
4. The water is used for fracturing and crushing the ores, and the method is environment-friendly and economical.
Drawings
FIG. 1 is a schematic diagram of a hydraulic fracturing rock breaking method of the present invention;
FIG. 2 is a schematic structural view of an actuator according to the present invention;
FIG. 3 is a schematic diagram of an embodiment of the present invention;
fig. 4 is a schematic view of an eyelet formed in a rock mass according to an embodiment of the present invention.
The names of the components represented by the reference numerals in the drawings are as follows:
1. a water storage tank; 2. a plunger pump; 3. an actuator; 3.1, a diamond drill bit; 3.2, water jet; 4. an eyelet; 4.1, perforating; 5. a low-pressure water pipe; 6. a high pressure water pipe; 7. the rock mass.
Detailed Description
The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.
Referring to fig. 1, a hydraulic fracturing system includes a water storage tank 1, a plunger pump 2 and an actuator 3, wherein the water storage tank 1 is used for storing water, the water storage tank 1 is connected with the plunger pump 2 through a low-pressure water pipe 5, the plunger pump 2 is connected with the actuator 3 through a high-pressure water pipe 6, and the plunger pump 2 is used for pressurizing water to obtain high-pressure water;
as shown in fig. 2, the head of the actuator 3 is a diamond bit 3.1, and the diamond bit 3.1 is used for drilling a hole 4 in a rock body 7; a water flow passage communicated with the outlet of the plunger pump 2 is arranged in the actuator 3, a plurality of water knives 3.2 communicated with the water flow passage are arranged on the outer wall of the middle part of the actuator 3, and the water knives 3.2 are used for spraying high-pressure water outwards to realize directional spraying in the holes 4, so that the perforation holes 4.1 are obtained; the tail of the actuator 3 is provided with a sealing element, and the sealing element is used for sealing a gap between the tail of the actuator 3 and the inner wall of the hole 4, so that the water pressure of a sealing area is maintained, the continuous extension of ore cracks is guaranteed, and the final ore crushing is achieved.
In the scheme, the 3.2 pressure of the water jet cutter is 137 Mpa. The water jet knives 3.2 are wide in layout, one part of the water jet knives are positioned at a position close to the diamond drill bit 3.1, the other part of the water jet knives are positioned at the middle position of the actuator 3, and each water jet knife 3.2 can be independently controlled to be opened or closed, for example, the wireless electric control valve block is utilized to realize the independent control of the water jet knives; the impact stress wave superposition effect generated by the jet flow of the water jet cutter 3.2 close to the diamond drill bit 3.1 position is utilized to lead the stress wave to generate cracks in the rock body 7, thereby damaging ores in a grading way and improving the rock breaking efficiency of the jet drill bit. Meanwhile, heat and ore fragments generated by cutting the ore by the diamond drill bit 3.1 are taken away by water flow, so that the loss of the drill bit is reduced, and the drilling quality is improved.
The arrangement of the water jet cutter 3.2 in the middle of the actuator 3 aims to obtain a perforation 4.1 for the directional injection inside the ore perforation 4, and is beneficial to achieving the fracturing effect. Meanwhile, the perforation 4.1 also has the functions of controlling the fracturing direction and reducing the number of drilled holes.
The afterbody of executor 3 is the sealing member, and the sealing member direct action maintains the encapsulated situation in punchhole 4 on the inner wall in punchhole 4, ensures that the water pressure of beating into in punchhole 4 does not reveal, and the guarantee ore crack can constantly extend, reaches final ore breakage.
The whole crushing process is divided into two parts, namely a drilling and perforating process and a fracturing and crushing process.
Step 1: the plunger pump 2 converts the low-pressure water in the water storage tank 1 into high-pressure water;
step 2: high-pressure water is conveyed to water knives 3.2 at the bottoms of the actuators 3 according to a designed pipeline, and a plurality of holes 4 are formed in the rock by matching with diamond drill bits 3.1;
and step 3: after drilling is completed, the diamond drill bit 3.1 and the water jet 3.2 beside the diamond drill bit stop working, the water jet 3.2 in the middle of the actuator 3 starts working, directional injection is realized in the perforation 4, and a perforation 4.1 is obtained;
and 5, finishing the fracturing of the section, and continuing to execute the operation process of the subsequent working section until the fracturing operation of the whole rock mass 7 is finished.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (10)
1. A hydraulic fracturing rock breaking method is characterized by comprising the following steps:
s1, drilling a plurality of holes in advance at the position of the rock body to be broken;
s2, pressurizing water to obtain high-pressure water;
and S3, injecting high-pressure water into the sealed hole, and continuously increasing the water pressure of the high-pressure water until the pressure in the hole exceeds the crack extension pressure of the rock mass, so that the rock mass is crushed.
2. A method of hydraulic fracturing rock breaking according to claim 1 wherein the perforations are previously impinged by high pressure water jets in the rock mass bore.
3. A method of hydraulic fracturing rock breaking as claimed in claim 1 or 2, wherein the breaking volume and direction of the rock mass are controlled by controlling the layout and number of perforations and perforations.
4. The hydraulic fracturing rock breaking system is characterized by comprising a water storage device, a pressurizing device and an actuator, wherein the water storage device is used for storing water, and the pressurizing device is used for pressurizing the water to obtain high-pressure water;
the actuator is used for drilling holes in a rock body, and a water flow passage communicated with a high-pressure water outlet of the pressurizing device is arranged in the actuator and used for injecting high-pressure water into the drilled holes.
5. The hydraulic fracturing rock breaking system of claim 4, wherein the head of the actuator is a drill bit; and the outer wall of the middle part of the actuator is provided with a plurality of water jet cutters communicated with the water flow passage, and the water jet cutters are used for utilizing high-pressure water flow to jet directionally in the holes of the rock body to obtain the perforation holes.
6. The hydraulic fracturing rock breaking system of claim 4, wherein each water jet is equipped with an independent control device for independently controlling the opening and closing of the water jet.
7. The hydraulic fracturing rock breaking system of claim 5, wherein the actuator tail is provided with a seal for sealing a gap between the actuator tail and the inner wall of the bore hole.
8. The hydraulic fracturing rock breaking system of claim 4, wherein the pressurizing device is a plunger pump.
9. The hydraulic fracturing rock breaking system of claim 7, wherein the actuator is a plurality of actuators.
10. The hydraulic fracturing rock breaking system of claim 5, wherein the drill bit is one of a roller cone bit, a drag bit, and a diamond bit.
Priority Applications (1)
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CN202111266773.0A CN113818878A (en) | 2021-10-28 | 2021-10-28 | Hydraulic fracturing rock breaking method and system |
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CN202111266773.0A CN113818878A (en) | 2021-10-28 | 2021-10-28 | Hydraulic fracturing rock breaking method and system |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114413695A (en) * | 2022-01-20 | 2022-04-29 | 叶澄 | Static hydraulic blasting device and construction process thereof |
CN115182744A (en) * | 2022-06-22 | 2022-10-14 | 安阳工学院 | Directional breaking device for rock |
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CN112647918A (en) * | 2020-12-29 | 2021-04-13 | 长江大学 | Hydraulic pulse reinforced hydraulic fracturing system |
CN214247218U (en) * | 2021-02-02 | 2021-09-21 | 陈晔 | Auxiliary rock breaking device for well drilling |
CN214247322U (en) * | 2020-12-01 | 2021-09-21 | 煤科集团沈阳研究院有限公司 | Orifice hydraulic device for preventing high-pressure push rod from spraying |
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CN102619469A (en) * | 2012-04-13 | 2012-08-01 | 辽宁工程技术大学 | Device for hole drilling, seam cutting and pressure relief of coal seam |
CN202745846U (en) * | 2012-07-12 | 2013-02-20 | 中国石油天然气股份有限公司 | Perforating, fracturing and sand washing integrated tubular column for coiled tubing |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
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CN114413695A (en) * | 2022-01-20 | 2022-04-29 | 叶澄 | Static hydraulic blasting device and construction process thereof |
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CN115182744A (en) * | 2022-06-22 | 2022-10-14 | 安阳工学院 | Directional breaking device for rock |
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