CN110671148B - One-hole multi-open ground grouting filling method above coal pillar - Google Patents
One-hole multi-open ground grouting filling method above coal pillar Download PDFInfo
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- CN110671148B CN110671148B CN201911102220.4A CN201911102220A CN110671148B CN 110671148 B CN110671148 B CN 110671148B CN 201911102220 A CN201911102220 A CN 201911102220A CN 110671148 B CN110671148 B CN 110671148B
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- 239000003245 coal Substances 0.000 title claims abstract description 95
- 238000000034 method Methods 0.000 title claims abstract description 37
- 238000005553 drilling Methods 0.000 claims abstract description 24
- 238000005516 engineering process Methods 0.000 claims abstract description 13
- 239000002002 slurry Substances 0.000 claims description 5
- 238000005065 mining Methods 0.000 claims description 4
- 238000011084 recovery Methods 0.000 claims description 4
- 238000000605 extraction Methods 0.000 claims 1
- 238000010276 construction Methods 0.000 abstract description 9
- 239000002910 solid waste Substances 0.000 abstract description 8
- 239000010881 fly ash Substances 0.000 abstract description 3
- -1 gangue Substances 0.000 abstract 1
- 239000010883 coal ash Substances 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000010878 waste rock Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005429 filling process Methods 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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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
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
- E21F15/06—Filling-up mechanically
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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)
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
Abstract
The invention discloses a one-hole multi-open ground grouting filling method above a coal pillar, which is characterized in that a grouting main drill hole is arranged above the coal pillar between working faces, after casing and well cementation are carried out on the grouting main drill hole, a plurality of secondary grouting drill holes are respectively constructed in working face goafs at two sides of the coal pillar through the grouting main drill hole, and the working face goafs at two sides of the coal pillar are subjected to high-pressure grouting filling by using a ground grouting pump, so that the purpose of treating solid wastes such as gangue is achieved. The invention can avoid the construction of grouting drill holes above the goaf, improve the safety of drilling construction and the stability of a drill hole structure, reduce the arrangement number of grouting drill holes, save the grouting cost and improve the applicability of the ground grouting filling technology in the underground filling field of solid wastes such as gangue, fly ash and the like.
Description
Technical Field
The invention relates to a grouting filling method, in particular to a one-hole multi-open ground grouting filling method above a coal pillar, which is suitable for underground disposal of solid wastes such as coal mine waste rocks and the like.
Background
In recent years, with the enhancement of social environmental protection awareness and the continuous tightening of environmental protection policies, the ground discharge resistance of solid wastes such as gangue and fly ash is getting larger and larger. The ground grouting filling technology provides a green treatment mode for solid wastes such as waste rock, coal ash and the like, and the technical principle is that grouting filling is carried out on a separation layer space or a goaf after the mining of a working face through a grouting drill hole constructed above the goaf, so that the purpose of treating the solid wastes such as the waste rock, the coal ash and the like is achieved.
However, the traditional ground grouting filling method has obvious disadvantages, which are mainly shown as follows: firstly, after a working face coal seam is mined, an overlying roof is in continuous movement and can be completely stable for several years, however, the drilling construction of the traditional ground grouting filling method is mostly positioned above a goaf, and certain hidden danger exists in the construction safety; the traditional ground grouting filling adopts single drill holes to perform grouting filling one by one, and due to poor slurry fluidity, a plurality of drill holes need to be arranged in the grouting filling process to complete grouting filling, so that the grouting cost is relatively high. Due to the two reasons, the application of the traditional ground grouting filling technology in the underground filling field of solid wastes such as coal mine gangue is limited to a certain extent, so that a safe, economic and efficient ground grouting filling method is urgently needed.
Disclosure of Invention
The invention aims to provide a one-hole multi-open ground grouting filling method above a coal pillar so as to achieve the purposes of improving the safety of ground drilling construction and reducing grouting filling cost.
The invention is realized by adopting the following technical scheme:
a one-hole multi-open ground grouting filling method above a coal pillar is characterized in that a section coal pillar is reserved between two adjacent coal faces according to a traditional coal face arrangement mode, and after the two adjacent coal faces are mined in sequence, grouting filling is carried out on working face goafs on two sides of the coal pillar through grouting drill holes arranged on the ground above the coal pillar; the grouting drill holes comprise a main grouting drill hole and a secondary grouting drill hole which are communicated from top to bottom; the method specifically comprises the following steps;
a. carrying out stoping operation on the first working face, the second working face and the third working face in sequence according to a traditional coal face arrangement form;
b. if the first working face and the second working face which are adjacent are stoped during grouting operation, arranging a group of main grouting drill holes on the ground above the first coal pillar between the first working face and the second working face, constructing secondary grouting drill holes in the goaf of the first working face and the goaf of the second working face from the main grouting drill holes by utilizing a directional drilling technology, and then sequentially connecting a grouting pipeline to the main grouting drill holes and the secondary grouting drill holes to perform grouting filling on the goaf of the first working face and the goaf of the second working face;
if the coal face is not mined during grouting operation, executing the following steps;
c. before the first working face is recovered, arranging a group of main grouting drill holes on the ground above a first coal pillar between the first working face and a second working face;
d. in the process of advancing the first working face, sequentially passing through each grouting main drilling hole; when the first working face is pushed to the position of 50-200 m from the first main grouting drill hole, constructing a secondary grouting drill hole from the first main grouting drill hole to the goaf of the first working face on the ground by utilizing a directional drilling technology, and then connecting a grouting pipeline to the first main grouting drill hole and the secondary grouting drill hole to perform grouting filling on the goaf of the first working face; the process is repeated along with the continuous propulsion of the first working face, secondary grouting drill holes are constructed in the goaf of the first working face by sequentially utilizing the ground grouting main drill holes, and grouting filling is carried out;
e. before stoping of the second working face, arranging a group of main grouting drill holes on the ground above the second coal pillar between the second working face and the third working face;
f. after the first working face is completely mined, the second working face sequentially passes through main grouting drill holes arranged in coal pillars on two sides of the second working face in the advancing process; when the second working face is pushed to the position of 50-200 m through the main grouting drill holes arranged in the coal pillars on the two sides, constructing a secondary grouting drill hole from the main grouting drill holes arranged in the coal pillars on the two sides to the goaf of the second working face by utilizing a directional drilling technology on the ground, and then connecting a slurry conveying pipeline to the main grouting drill holes arranged in the coal pillars on the two sides of the second working face and the secondary grouting drill hole to perform grouting filling on the goaf of the second working face; the process is repeated along with the continuous propulsion of the second working face, and the goaf is grouted and filled by using the main grouting drill hole and the secondary grouting drill hole which are arranged in the first coal pillar and the second coal pillar on the two sides of the second working face in sequence;
g. and repeating the process, and sequentially performing grouting filling on the subsequent working surface.
The invention is further improved in that the ground grouting main drilling hole is of a single-opening single-pipe structure or a multi-opening multi-pipe structure.
The invention is further improved in that when a secondary grouting drill hole is constructed from the main grouting drill hole to the working face goaf, one or more secondary grouting drill holes are constructed and grouting filling is carried out simultaneously.
The invention has the further improvement that the secondary grouting drill hole enters the caving zone of the working face by at least 5-10 m.
The method is further improved in that the distance between every two adjacent main grouting drill holes is 50-200 m, and the main grouting drill holes are constructed to the mining height 3-10 times higher than the coal seam.
The invention is further improved in that the coal pillar is a section protection coal pillar, a boundary protection coal pillar, a roadway protection coal pillar, a third protection coal pillar or an unexplored coal pillar.
The invention has at least the following beneficial technical effects:
according to the one-hole multi-open ground grouting filling method above the coal pillar, the grouting drill holes are arranged in the stable area above the coal pillar, so that potential safety hazards caused by drilling construction above a goaf can be avoided, the construction difficulty of the drill holes is reduced, and the construction safety and the stability of the drill holes are improved; on the other hand, the arrangement form of drilling holes with one hole and multiple holes is adopted, the arrangement quantity of ground drilling holes can be reduced, the drilling construction cost of grouting filling is reduced, and the applicability of the ground grouting filling technology in the underground filling field of solid wastes such as gangue and fly ash is improved.
Drawings
FIG. 1 is a schematic plan view of a face layout of a panel of the present invention;
FIG. 2 is a schematic plan view of a grouting drilling arrangement of the present invention;
figure 3 is a schematic cross-sectional view of a grouted borehole arrangement of the present invention.
Description of reference numerals:
1. a coal face; 2. a coal pillar; 3. grouting and drilling; 4. a first working surface; 5. a second working surface; 6. working surface III; 7. a first coal pillar; 8. a second coal pillar; 9. grouting a main drilling hole; 10. secondary grouting and drilling; 11. a slurry conveying pipeline.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
As shown in fig. 1 to 3, according to the one-hole multi-open ground grouting filling method above a coal pillar provided by the invention, according to the arrangement form of a traditional coal face 1, namely, a section coal pillar 2 is reserved between two adjacent coal faces 1, after two adjacent coal faces 1 are mined in sequence, grouting filling is carried out on the working face goafs at two sides of the coal pillar 2 by arranging a grouting drill hole 3 on the ground above the coal pillar 2; the grouting drill holes 3 comprise a main grouting drill hole 9 and a secondary grouting drill hole 10 which are communicated from top to bottom; the method specifically comprises the following steps;
a. carrying out stoping operation on the first working face 4, the second working face 5 and the third working face 6 in sequence according to a traditional coal face arrangement form;
b. if grouting operation is carried out, stoping of the adjacent first working face 4 and second working face 5 is finished, arranging a group of main grouting drill holes 9 on the ground above the first coal pillar 7 between the first working face 4 and the second working face 5, constructing secondary grouting drill holes 10 in goafs of the first working face 4 and the second working face 5 through the main grouting drill holes 9 by utilizing a directional drilling technology, and then sequentially connecting a grouting pipeline 11 to the main grouting drill holes 9 and the secondary grouting drill holes 10 to carry out grouting filling on the goafs of the first working face 4 and the second working face 5;
if the coal face is not mined during grouting operation, executing the following steps;
c. before the first working face 4 is recovered, arranging a group of main grouting drill holes 9 on the ground above a first coal pillar 7 between the first working face 4 and a second working face 5;
d. in the process of pushing the working face 4, the working face sequentially passes through the main grouting drill holes 9; when the first working face 4 pushes the first main grouting drill hole 9 to the position of 50-200 m, constructing a secondary grouting drill hole 10 from the first main grouting drill hole 9 to the goaf of the first working face 4 on the ground by utilizing a directional drilling technology, and then connecting a grouting pipeline 11 to the first main grouting drill hole 9 and the secondary grouting drill hole 10 to perform grouting filling on the goaf of the first working face 4; the process is repeated with the continuous propulsion of the first working face 4, secondary grouting drill holes 10 are constructed in the goaf of the first working face 4 by sequentially utilizing the ground grouting main drill holes 9, and grouting filling is carried out;
e. the recovery of the first working face 4 is about to be completed, and before the recovery of the second working face 5, a group of main grouting drill holes 9 are arranged on the ground above a second coal pillar 8 between the second working face 5 and a third working face 6;
f. after the recovery of the working face I4 is finished, the working face II 5 passes through main grouting drill holes 9 arranged in coal pillars on two sides of the working face I in sequence in the advancing process; when the second working face 5 pushes the main grouting drill holes 9 arranged in the coal pillars at two sides to 50-200 m, constructing secondary grouting drill holes 10 from the main grouting drill holes 9 arranged in the coal pillars at two sides to the goaf of the second working face 5 by utilizing a directional drilling technology on the ground, and then connecting a slurry conveying pipeline 11 to the main grouting drill holes 9 arranged in the coal pillars at two sides of the second working face 5 and the secondary grouting drill holes 10 to perform grouting filling on the goaf of the second working face 5; the process is repeated along with the continuous propulsion of the second working surface 5, and the goaf is grouted and filled by the grouting main drill hole 9 and the secondary grouting drill hole 10 which are arranged in the first coal pillar 7 and the second coal pillar 8 on the two sides of the second working surface 5 in sequence;
g. and repeating the process, and sequentially performing grouting filling on the subsequent working surface.
The main grouting drill hole 9 is of a single-pipe structure or a multi-pipe structure.
When the secondary grouting drill hole 10 is constructed from the main grouting drill hole 9 to the working face goaf, one or more secondary grouting drill holes 10 can be constructed and grouting filling can be carried out simultaneously.
The secondary grouting drilling hole 10 needs to enter a working face caving area for at least 5-10 m.
The distance between every two adjacent main grouting drill holes 9 is 50-200 m, and the main grouting drill holes 9 need to be constructed to the mining height 3-10 times higher than the coal seam.
The coal pillar 2 is a section protection coal pillar, a boundary protection coal pillar, a roadway protection coal pillar, a third lower protection coal pillar or a coal pillar which is not exploited yet.
Claims (6)
1. A one-hole multi-open ground grouting filling method above a coal pillar is characterized in that according to a traditional coal face (1) arrangement mode, namely, a section coal pillar (2) is reserved between two adjacent coal faces (1), and after two adjacent coal faces (1) are mined in sequence, grouting is performed on working face goafs on two sides of the coal pillar (2) by arranging grouting drill holes (3) on the ground above the coal pillar (2); the grouting drill holes (3) comprise a main grouting drill hole (9) and a secondary grouting drill hole (10) which are communicated from top to bottom; the method specifically comprises the following steps;
a. carrying out stoping operation on a first working face (4), a second working face (5) and a third working face (6) in sequence according to a traditional coal face arrangement form;
b. if the stoping of the adjacent first working face (4) and second working face (5) is finished during the grouting operation, arranging a group of main grouting drill holes (9) on the ground above the first coal pillar (7) between the first working face (4) and the second working face (5), constructing secondary grouting drill holes (10) in the goaf of the first working face (4) and the second working face (5) through the main grouting drill holes (9) by utilizing the directional drilling technology, and then sequentially connecting a grouting pipeline (11) to the main grouting drill holes (9) and the secondary grouting drill holes (10) to perform grouting filling on the goaf of the first working face (4) and the second working face (5);
if the coal face is not mined during grouting operation, executing the following steps;
c. before the first working face (4) is mined, arranging a group of main grouting drill holes (9) on the ground above a first coal pillar (7) between the first working face (4) and a second working face (5);
d. in the advancing process of the first working face (4), the first working face sequentially passes through all the main grouting drill holes (9); when the first working face (4) pushes the first main grouting drill hole (9) to a position of 50-200 m, constructing a secondary grouting drill hole (10) from the first main grouting drill hole (9) to the goaf of the first working face (4) on the ground by utilizing a directional drilling technology, and then connecting a grouting pipeline (11) to the first main grouting drill hole (9) and the secondary grouting drill hole (10) to perform grouting filling on the goaf of the first working face (4); the process is repeated along with the continuous propulsion of the first working face (4), secondary grouting drill holes (10) are constructed to the goaf of the first working face (4) by sequentially utilizing the ground grouting main drill holes (9), and grouting filling is carried out;
e. the first working face (4) is about to finish the recovery, and before the second working face (5) recovers, a group of main grouting drill holes (9) are arranged on the ground above a second coal pillar (8) between the second working face (5) and a third working face (6);
f. after the first working face (4) finishes the extraction, the second working face (5) passes through main grouting drill holes (9) arranged in coal pillars on two sides of the first working face in sequence in the advancing process; when the second working face (5) is pushed to the position of 50-200 m through the main grouting drill holes (9) arranged in the coal pillars on the two sides, constructing secondary grouting drill holes (10) from the main grouting drill holes (9) arranged in the coal pillars on the two sides to the goaf of the second working face (5) by utilizing a directional drilling technology on the ground, and then connecting a slurry conveying pipeline (11) to the main grouting drill holes (9) arranged in the coal pillars on the two sides of the second working face (5) and the secondary grouting drill holes (10) to perform grouting filling on the goaf of the second working face (5); the process is repeated along with the continuous propulsion of the second working surface (5), and the goaf is grouted and filled by using the main grouting drill hole (9) and the secondary grouting drill hole (10) which are arranged in the first coal pillar (7) and the second coal pillar (8) on the two sides of the second working surface (5) in sequence;
g. and repeating the process, and sequentially performing grouting filling on the subsequent working surface.
2. The method for filling the one-hole multi-open ground grouting above the coal pillar according to the claim 1, characterized in that the ground grouting main drilling hole (9) is of a single-pipe structure or a multi-pipe structure.
3. The above-coal-pillar one-hole multiple-open-type ground grouting filling method according to claim 1, characterized in that when the secondary grouting drill holes (10) are constructed from the main grouting drill holes (9) to the goaf of the working face, one or more secondary grouting drill holes (10) are constructed and grouting filling is carried out simultaneously.
4. The above coal pillar one-hole multiple-open ground grouting filling method as claimed in claim 1, characterized in that the secondary grouting drill hole (10) enters the caving zone of the working face by at least 5-10 m.
5. The method for grouting and filling the ground with one hole and multiple openings above the coal pillar according to claim 1, wherein the distance between two adjacent main grouting drill holes (9) is 50-200 m, and the main grouting drill holes (9) are constructed to the mining height 3-10 times higher than the coal seam.
6. The above-coal-pillar one-hole multi-open ground grouting filling method as claimed in claim 1, characterized in that the coal pillar (2) is a section protection coal pillar, a boundary protection coal pillar, a roadway protection coal pillar, a three-lower protection coal pillar or an unexplored coal pillar.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911102220.4A CN110671148B (en) | 2019-11-12 | 2019-11-12 | One-hole multi-open ground grouting filling method above coal pillar |
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| CN201911102220.4A CN110671148B (en) | 2019-11-12 | 2019-11-12 | One-hole multi-open ground grouting filling method above coal pillar |
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| CN110671148B true CN110671148B (en) | 2020-10-27 |
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| CN111794799A (en) * | 2020-07-16 | 2020-10-20 | 中煤天津设计工程有限责任公司 | Solid waste treatment technology for ground drilling, grouting and filling of old goaf |
| CN113006862A (en) * | 2021-03-29 | 2021-06-22 | 张连杰 | Novel technology for treating coal mining subsidence area by backfilling from ground drilling |
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| SU597863A2 (en) * | 1976-12-15 | 1978-03-15 | Bitimbaev Marat Z | Method of building artificial pillar |
| CN102383779B (en) * | 2011-07-06 | 2015-04-01 | 宏大矿业有限公司 | Double-layer gob drilling exploration method |
| CN103821538B (en) * | 2013-12-26 | 2016-09-07 | 安徽理工大学 | J-type horizontal assistant branched hole surface advance grouting paste-making method |
| CN105822305A (en) * | 2016-03-15 | 2016-08-03 | 淮北矿业（集团）勘探工程有限责任公司 | Overlying strata settlement reducing method for coal mining through isolated grouting and bashing |
| CN106705773B (en) * | 2016-09-14 | 2019-06-04 | 中国矿业大学 | A kind of method of surface drilling presplit blasting shallow embedding room formula goaf top plate |
| CN109854297B (en) * | 2019-02-22 | 2021-01-29 | 中煤科工集团西安研究院有限公司 | Small coal kiln goaf grouting method based on directional drilling process |
| CN109899089A (en) * | 2019-03-07 | 2019-06-18 | 中煤科工集团西安研究院有限公司 | Goaf grouting method based on pinniform horizontal branch directional drilling technique |
| CN110173301B (en) * | 2019-05-09 | 2020-11-24 | 中煤科工集团西安研究院有限公司 | Fully mechanized goaf grouting method based on cluster multilateral well directional drilling |
| CN110273685B (en) * | 2019-06-13 | 2020-12-29 | 太原理工大学 | Microwave heating H-type method for reducing composite strong mine pressure of thick hard roof and left coal pillar |
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