CN113404534B - Method for preventing rock burst by staged fracturing of L-shaped ground horizontal well - Google Patents
Method for preventing rock burst by staged fracturing of L-shaped ground horizontal well Download PDFInfo
- Publication number
- CN113404534B CN113404534B CN202110770986.0A CN202110770986A CN113404534B CN 113404534 B CN113404534 B CN 113404534B CN 202110770986 A CN202110770986 A CN 202110770986A CN 113404534 B CN113404534 B CN 113404534B
- Authority
- CN
- China
- Prior art keywords
- fracturing
- well
- horizontal
- horizontal section
- section
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F17/00—Methods or devices for use in mines or tunnels, not covered elsewhere
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C41/00—Methods of underground or surface mining; Layouts therefor
- E21C41/16—Methods of underground mining; Layouts therefor
- E21C41/18—Methods of underground mining; Layouts therefor for brown or hard coal
Abstract
The invention discloses a method for preventing rock burst by staged fracturing of an L-shaped ground horizontal well, which comprises the following steps: determining a fracturing layer position and fracturing intervals; constructing an L-shaped horizontal well vertical section on the ground, and embedding a sleeve to fix a well wall; beginning deflecting at the design point A and extending to a fracturing horizon, and beginning constructing a horizontal section of the 1# well when drilling to the horizontal direction; adopting a backward fracturing 1# well horizontal section; plugging a deflecting section of the No. 1 well, extending the vertical well, deflecting in the opposite direction at a position which is not smaller than 10m below a design point A, extending to a fracturing layer, and constructing a horizontal section of the No. 2 well when drilling to the horizontal direction; and adopting a backward type fracturing 2# well horizontal section. According to the invention, the hard and difficult-to-collapse rock stratum is covered on the coal face to carry out high-pressure hydraulic sectional fracturing, so that the coal face is regularly collapsed, the rock stratum large-area suspended roof is prevented from suddenly straddling to induce the rock burst of the coal face, and the safe and efficient mining of a mine is realized.
Description
Technical Field
The invention belongs to the technical field of coal face impact disaster prevention and control methods, and particularly relates to a method for preventing and controlling rock burst by staged fracturing of an L-shaped ground horizontal well.
Background
Rock burst is one of main disasters faced by deep mine coal mining, and has been increasingly developed in China in recent years, and immeasurable losses are caused to mines and personnel. According to statistics, the roof-type rock burst of the coal face of the deep mine accounts for more than three fourths of the rock burst accidents of the coal face, the main induction factor of the roof-type rock burst of the coal face is that large dynamic load is generated by sudden falling of large-area suspended roofs of hard and thick rock formations above a roof of a coal bed, and the high static load of the superimposed working faces induces the rock burst of the coal face, so that how to avoid the large-area suspended roofs of the hard roof of the coal face becomes a main research direction for solving the roof-type rock burst.
Disclosure of Invention
The invention aims to provide a method for preventing rock burst by staged fracturing of an L-shaped ground horizontal well, which solves the problem that the rock burst of a coal face is induced by sudden falling of a large-area suspended ceiling of a hard top plate of the existing coal face.
The technical scheme adopted by the invention is as follows: a method for preventing rock burst by staged fracturing of an L-shaped ground horizontal well comprises the following steps:
step 1, determining a fracturing horizon and fracturing intervals;
step 2, constructing an L-shaped horizontal well vertical section on the ground, and embedding a sleeve to fix a well wall;
step 3, deflecting is started at the design point A and extends to a fracturing layer, and a horizontal section of the 1# well is constructed when the horizontal direction is drilled;
step 4, adopting a backward fracturing 1# well horizontal section;
step 5, plugging a deflecting section of the 1# well after the fracturing of the horizontal section of the 1# well is completed, extending the vertical well, deflecting reversely at a position which is not smaller than 10m below a design point A, extending to a fracturing layer, and constructing the horizontal section of the 2# well when drilling to the horizontal direction;
and 6, adopting a horizontal section of the backward fracturing 2# well.
The present invention is also characterized in that,
in the step 1, a key layer of the coal face is determined according to a mine geological synthetic histogram, three-zone observation of an adjacent working face, theoretical calculation and numerical simulation, a direct cross-falling layer is determined according to the mine geological synthetic histogram, a microseismic event and a seismic source position, and then a rock stratum between the key layer and the direct collapse layer is selected to be determined as a fracturing layer.
In the step 1, the caving step distance of the rock stratum above the coal seam roof of the coal face is determined according to the number of microseismic events and the working resistance of the hydraulic support of the working face, and the fracturing step distance is determined to be 1/2-1/3 of the caving step distance.
The step 4 specifically comprises the following steps:
step 4.1, adopting perforating charges to eject 4-6 clusters of perforation holes around the hole wall at the fracturing position;
step 4.2, arranging 2 bridge plugs within a range of 20-50 m before and after shower holes for blocking;
step 4.3, injecting high-pressure water into the 2 bridge plugs, and carrying out 360-degree fracturing on the high-pressure water through perforation;
and 4.4, after the fracturing is completed for a section, repeating the steps 4.1-4.3 at the next fracturing position until the horizontal section of the No. 1 well is completely fractured.
The horizontal section of the 2# well is the same as the horizontal section of the 1# well in a back-off fracturing mode.
The beneficial effects of the invention are as follows: according to the method for preventing and controlling rock burst through staged fracturing of the L-shaped ground horizontal well, the coal face is covered with the hard and difficult-to-collapse rock stratum to be subjected to high-pressure hydraulic staged fracturing, so that the rock stratum is regularly collapsed, the rock stratum is prevented from suddenly straddling and inducing the rock burst of the coal face in a large-area suspended roof, and safe and efficient mining of a mine is achieved.
Drawings
FIG. 1 is a state diagram of an implementation of a method for controlling rock burst by staged fracturing of an L-shaped ground horizontal well;
FIG. 2 is a partial state diagram of a whipstock section in a method for controlling rock burst by staged fracturing of an L-shaped ground horizontal well according to the present invention.
Detailed Description
The invention will be described in detail with reference to the accompanying drawings and detailed description.
The invention provides a method for preventing rock burst by staged fracturing of an L-shaped ground horizontal well, which is shown in fig. 1 and 2 and comprises the following steps:
step 1, determining a key layer of a coal face by mine geological synthetic histogram, three-zone observation (collapse zone, fracture zone and bending sinking zone) of an adjacent working face, theoretical calculation and numerical simulation, determining a direct cross-falling layer according to the mine geological synthetic histogram, a microseismic event and a seismic source position, and then selecting a hard thick rock stratum between the key layer and the direct collapse layer to determine a fracturing layer; determining the caving step distance of a hard thick rock layer above a coal seam roof of the coal face according to the number of microseismic events and the working resistance of a hydraulic support of the working face, wherein the fracturing step distance is determined to be 1/2-1/3 of the caving step distance;
step 2, repairing the road surface, erecting a derrick, constructing an L-shaped horizontal well vertical section on the ground, embedding a sleeve to fix the well wall, and preventing groundwater from invading the well wall;
step 3, starting deflecting at a design point A after the construction of the vertical well section is finished, accurately controlling a drill bit to accurately drill along the design deflecting section by utilizing a comprehensive geosteering drilling technology, and accurately continuing to drill horizontally according to the length of the design horizontal section after the target rock stratum fracturing section horizontally lands, so as to start constructing the 1# well horizontal section;
and 4, after the construction of the horizontal section of the 1# well is completed, starting to carry out staged fracturing on the target rock stratum by using high-pressure water. The hydraulic fracturing adopts a back-off type, and specifically comprises the following steps:
step 4.1, adopting perforating charges to eject 4-6 clusters of perforation holes around the hole wall at the fracturing position;
step 4.2, arranging 2 bridge plugs within a range of 20-50 m (based on the condition that the fracturing interval is not exceeded) before and after the shower hole for blocking;
step 4.3, injecting high-pressure water into the 2 bridge plugs, and carrying out 360-degree fracturing on the high-pressure water through perforation;
step 4.4, after fracturing for a period, repeating the steps 4.1-4.3 at the next fracturing position until the horizontal section of the 1# well is fractured;
step 5, plugging a deflecting section of the 1# well after the fracturing of the horizontal section of the 1# well is completed, extending the vertical well, deflecting reversely at a position which is not smaller than 10m below a design point A, extending to a fracturing layer, and constructing the horizontal section of the 2# well in the same mode as the 1# well when the horizontal section is drilled to the horizontal direction;
and 6, after the construction of the horizontal section of the 2# well is finished, repeating the step 4 to crack the horizontal section of the 2# well by adopting a backward type until the horizontal section of the 2# well is completely cracked.
According to the method for preventing and controlling rock burst by staged fracturing of the L-shaped ground horizontal well, the coal face is covered with the hard and difficult-to-collapse rock stratum to be subjected to high-pressure hydraulic staged fracturing, so that the rock stratum is regularly collapsed, the rock stratum is prevented from suddenly straddling and falling over a large area, the rock stratum is prevented from inducing the rock burst of the coal face, and safe and efficient mining of a mine is realized. The method also has the following characteristics:
1. all the devices related by the invention are on the ground, and compared with underground construction, the size, the power and the number of the devices are not limited, so that better, faster and more economical construction can be realized.
2. Compared with conventional blasting, hydraulic fracturing is adopted, so that the hydraulic fracturing is safer.
3. The two-purpose well is realized, the L-shaped horizontal wells in 2 different directions are constructed by repeatedly utilizing the vertical shaft section, and the economical efficiency is better.
Claims (1)
1. The method for preventing rock burst by staged fracturing of the L-shaped ground horizontal well is characterized by comprising the following steps of:
step 1, determining a fracturing horizon and fracturing intervals; the method comprises the following steps: determining a key layer of a coal face according to a mine geological synthetic histogram, three-zone observation of an adjacent working face, theoretical calculation and numerical simulation, determining a direct cross-falling layer according to the mine geological synthetic histogram, a microseismic event and a seismic source position, and then selecting a rock stratum between the key layer and the direct falling layer to determine a fracturing layer; determining the caving step distance of the rock stratum above the coal seam roof of the coal face according to the number of microseismic events and the working resistance of the hydraulic support of the working face, wherein the fracturing step distance is determined to be 1/2-1/3 of the caving step distance;
step 2, constructing an L-shaped horizontal well vertical section on the ground, and embedding a sleeve to fix a well wall;
step 3, deflecting is started at the design point A and extends to a fracturing layer, and a horizontal section of the 1# well is constructed when the horizontal direction is drilled;
step 4, adopting a backward fracturing 1# well horizontal section; the method specifically comprises the following steps:
step 4.1, adopting perforating charges to eject 4-6 clusters of perforation holes around the hole wall at the fracturing position;
step 4.2, arranging 2 bridge plugs within a range of 20-50 m before and after shower holes for blocking;
step 4.3, injecting high-pressure water into the 2 bridge plugs, and carrying out 360-degree fracturing on the high-pressure water through perforation;
step 4.4, after fracturing for a period, repeating the steps 4.1-4.3 at the next fracturing position until the horizontal section of the 1# well is fractured; the horizontal section of the 2# well is the same as the horizontal section of the 1# well in a back-off fracturing mode;
step 5, plugging a deflecting section of the 1# well after the fracturing of the horizontal section of the 1# well is completed, extending the vertical well, deflecting reversely at a position which is not smaller than 10m below a design point A, extending to a fracturing layer, and constructing the horizontal section of the 2# well when drilling to the horizontal direction;
and 6, adopting a horizontal section of the backward fracturing 2# well.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110770986.0A CN113404534B (en) | 2021-07-07 | 2021-07-07 | Method for preventing rock burst by staged fracturing of L-shaped ground horizontal well |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110770986.0A CN113404534B (en) | 2021-07-07 | 2021-07-07 | Method for preventing rock burst by staged fracturing of L-shaped ground horizontal well |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113404534A CN113404534A (en) | 2021-09-17 |
| CN113404534B true CN113404534B (en) | 2023-05-02 |
Family
ID=77685581
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110770986.0A Active CN113404534B (en) | 2021-07-07 | 2021-07-07 | Method for preventing rock burst by staged fracturing of L-shaped ground horizontal well |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113404534B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113847083B (en) * | 2021-10-28 | 2024-03-01 | 重庆大学 | Control method for rock burst of high-level huge-thickness hard top plate area |
| CN115030718B (en) * | 2022-04-26 | 2023-04-14 | 重庆大学 | Method for preventing and controlling impact mine pressure of thick and hard rock stratum through regional hydraulic fracturing |
| CN115288654A (en) * | 2022-07-28 | 2022-11-04 | 陕西彬长孟村矿业有限公司 | Method for relieving pressure and preventing rock burst in blasting of ground horizontal well |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2915624C (en) * | 2015-12-18 | 2022-08-30 | Modern Wellbore Solutions Ltd. | Tool assembly and process for drilling branched or multilateral wells with whipstock |
| CN105807312B (en) * | 2016-03-15 | 2018-01-26 | 大连理工大学 | Coal mine roof plate rock mass vertical zoning based on micro seismic monitoring determines method |
| CN109505577B (en) * | 2018-11-12 | 2020-09-29 | 重庆科技学院 | Method for exploiting dry hot rock |
| CN111520119B (en) * | 2020-04-28 | 2022-04-08 | 中煤科工集团西安研究院有限公司 | Method for efficiently extracting coal bed gas by staged fracturing of large-spacing thin coal seam group multi-bottom horizontal well |
| CN112855087A (en) * | 2021-03-22 | 2021-05-28 | 河北佐和佑石油技术发展有限公司 | Coal bed gas horizontal well system transformation method |
-
2021
- 2021-07-07 CN CN202110770986.0A patent/CN113404534B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113404534A (en) | 2021-09-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113404534B (en) | Method for preventing rock burst by staged fracturing of L-shaped ground horizontal well | |
| CN111005723B (en) | Ground large-range rock stratum pre-splitting area anti-impact method based on up-down combined arrangement | |
| CN112593936B (en) | Advanced comprehensive control method for multi-disaster area of deep mine | |
| CN113404535B (en) | Method for preventing rock burst by hydraulic fracturing of coal mine underground | |
| WO2023273091A1 (en) | Method for preventing and controlling rock bursts in development roadway group | |
| CN104863629A (en) | Method for extracting gas from separation layer below overlying strata, draining water and grouting through combined drill hole | |
| CN103643918B (en) | A kind of searching for Ordovician limestone mining area and the method preventing mine from seeping water | |
| CN112780340B (en) | Method for preventing rock burst in advance in underground coal mine area | |
| CN102392677A (en) | Permeability improvement technology for coal bed gas reservoir cap by using three-dimensional fracture network modification | |
| CN111827878B (en) | Method for quickly and accurately probing hidden water inrush channel of coal seam floor | |
| CN112879011B (en) | Method for controlling height of water guide crack zone by hard overburden rock pre-cracking weakening under aquifer | |
| AU2021106168A4 (en) | High-gas Coal Seam Group Pressure Relief Mining Method Based on Gob-side Entry Retaining in the First Mining Whole Rock Pressure Relief Working Face | |
| CN103953386A (en) | Upstream-blocking and downstream-seepage method for extracting gas in mining area | |
| CN101280687A (en) | Projecting coal bed edge top drill construction technique and method for eliminating pumping blind zone | |
| CN109611146B (en) | Separation layer water drainage grouting method | |
| CN106869966A (en) | A kind of method for blocking of absciss layer water supply source | |
| WO2023197573A1 (en) | Impact-prevention pressure-relief tunneling method for rock burst coal seam roadway | |
| CN103216264A (en) | Method for controlling deformation of surrounding rock of basic rimrock layer on presplitting blasting mining roadway | |
| CN107620581B (en) | Construction method of one-well dual-purpose coal mine shaft inspection hole | |
| CN114294046B (en) | Coal mine area full-coverage underground three-dimensional extraction method | |
| CN113216912A (en) | Perforating gun for reducing mine earthquake grade and method for reducing mine earthquake grade through hydraulic fracturing | |
| CN111946343A (en) | Method for solving hard top plate collapse problem through ground vertical hole composite jet fracturing | |
| Han et al. | Exploitation technology of pressure relief coalbed methane in vertical surface wells in the Huainan coal mining area | |
| CN116771348A (en) | Method for reducing dynamic pressure influence of main roadway in last mining and optimizing stoping line coal pillar | |
| CN113107589B (en) | Advanced pre-drainage method for coal seam roof aquifer ground |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |