CN103742188B - Colliery drawing-off gas well and boring method - Google Patents
Colliery drawing-off gas well and boring method Download PDFInfo
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- CN103742188B CN103742188B CN201410007044.7A CN201410007044A CN103742188B CN 103742188 B CN103742188 B CN 103742188B CN 201410007044 A CN201410007044 A CN 201410007044A CN 103742188 B CN103742188 B CN 103742188B
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- 238000000034 method Methods 0.000 title claims abstract description 27
- 239000003245 coal Substances 0.000 claims description 37
- 239000011435 rock Substances 0.000 claims description 5
- 238000009412 basement excavation Methods 0.000 abstract description 13
- 239000012141 concentrate Substances 0.000 abstract description 2
- 238000005553 drilling Methods 0.000 description 5
- 230000008569 process Effects 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 230000000903 blocking effect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Abstract
The invention provides a kind of colliery drawing-off gas well and boring method, wherein, colliery drawing-off gas well includes: straight well；Horizontal well, connects with straight well；Horizontal branch well, connects with horizontal well, and horizontal branch well includes the first horizontal branch well being positioned at the upper area of colliery layer；Boring method includes: offer straight well；Offering the horizontal well connected with straight well, the horizontal well offered is inclined to against ore bed；Offering the horizontal branch well connected with horizontal well, horizontal branch well includes the first horizontal branch well being positioned at the upper area of colliery layer.The drawing-off gas well of present invention offer and boring method, first horizontal branch well is set in the upper area of colliery layer, gas in the layer of colliery the most all concentrates on upper area, so, on the top of colliery layer, horizontal branch well is set, can more up hill and dale before mine excavation by gas exhaust out, reduce repeatedly drawing-off gas during mine excavation, improve the safety of mine excavation.
Description
Technical field
The present invention relates to technical field of coal mine, especially, relate to a kind of colliery drawing-off gas well and boring method.
Background technology
At present, it is that surface orientation horizontal well is with straight that the ground that coal mine gas pump drainage is used connects pump drainage method with down-hole
Well creeps into connection, and horizontal branch well is laid in pinniform.But, due to not enough in early-stage preparations, existing for coal
The well construction of ore deposit drawing-off gas has many deficiencies, thus causes occurring various problem during drawing-off gas,
Wherein, the most serious problem is exactly before mine excavation, and the drawing-off gas well crept into always cannot be utilized to contain
Out, the process at mine excavation yet suffers from larger amount of gas to the pump drainage the most up hill and dale of gas within coal mines,
Add the potential safety hazard of coal production.
Summary of the invention
Present invention aim at providing a kind of colliery drawing-off gas well and boring method, to solve existing colliery pump drainage
The technical problem that gas well easily blocks, gas exhaust amount is limited.
For achieving the above object, according to an aspect of the invention, it is provided a kind of colliery drawing-off gas well, wrap
Include: straight well；Horizontal well, horizontal well is inclined to against ore bed, and connects with straight well；Horizontal branch well, with horizontal well even
Logical, horizontal branch well includes the first horizontal branch well being positioned at the upper area of colliery layer, the first horizontal branch well
Axis and colliery layer end face distance is the thickness there be not ore bed 1/3rd；Horizontal branch well also includes being positioned at
The second horizontal branch well in following coal mine gallery digging district, by the between straight well and following coal mine gallery digging district
Two horizontal branch wells connect indirectly.
Further, horizontal well is positioned at the bottom of colliery layer and extends along the vertical direction moved towards with colliery layer.
Further, horizontal branch well extends along the axially in parallel direction with following coal mine gallery.
According to another aspect of the present invention, additionally provide the boring method of a kind of colliery drawing-off gas well, including:
Offer straight well；Offer the inverse ore bed tendency horizontal well connected with straight well；Offer the horizontal branch connected with horizontal well
Well, wherein, offers the horizontal branch well connected with horizontal well, including: offer the upper area being positioned at colliery layer
The first horizontal branch well, and using the aspect of 1/3rd with the thickness that distance is colliery layer of the end face of colliery layer as
The plane at the axis place of one horizontal branch well offers the first horizontal branch well；Offer the horizontal branch well connected with horizontal well also to wrap
Include: in following coal mine gallery digging district, offer the second horizontal branch well, by the between straight well and following coal mine gallery digging district
Two horizontal branch wells connect indirectly.
Further, before offering straight well, also include: move angle according to the rock in following coal mine gallery digging district and determine directly
Well offer position so that straight well residing ore bed be moved afterwards keep connect with horizontal well.
Further, offer the horizontal well connected with straight well, comprise determining that the ore bed tendency in colliery to be dug；?
Horizontal well is offered along the vertical direction moved towards with ore bed in the bottom of ore bed.
Further, offer, along the axially in parallel direction digging tunnel with future, the level connected with horizontal well to divide
Zhi Jing.
The method have the advantages that
The invention provides a kind of colliery drawing-off gas well and boring method, wherein, colliery drawing-off gas Jing Bao
Include: straight well；Horizontal well, connects with straight well；Horizontal branch well, connects with horizontal well, and horizontal branch well includes position
The first horizontal branch well in the upper area of colliery layer；Boring method includes: offer straight well；Offer and straight well
The horizontal well of connection；Offering the horizontal branch well connected with horizontal well, horizontal branch well includes being positioned at the upper of colliery layer
The first horizontal branch well in region, portion.The drawing-off gas well of present invention offer and boring method, at colliery layer
Arranging the first horizontal branch well in upper area, the gas in the layer of colliery the most all concentrates on upper area, so,
Horizontal branch well is set on the top of colliery layer, it is possible to more up hill and dale before mine excavation by gas exhaust out,
Reduce repeatedly drawing-off gas during mine excavation, improve the safety of mine excavation.
In addition to objects, features and advantages described above, the present invention also has other purpose, feature and excellent
Point.Below with reference to figure, the present invention is further detailed explanation.
Accompanying drawing explanation
The accompanying drawing of the part constituting the application is used for providing a further understanding of the present invention, and the present invention's is schematic
Embodiment and explanation thereof are used for explaining the present invention, are not intended that inappropriate limitation of the present invention.In the accompanying drawings:
Fig. 1 is the structural representation of the colliery drawing-off gas well of the preferred embodiment of the present invention.
Detailed description of the invention
Below in conjunction with accompanying drawing, embodiments of the invention are described in detail, but the present invention can be limited by claim
Multitude of different ways that is fixed and that cover is implemented.
One aspect of the present invention, it is provided that the boring method of a kind of colliery drawing-off gas well, the method includes: first
First, straight well is offered；Then, the horizontal well B connected with this straight well is offered；Finally, offer and connect with horizontal well B
Horizontal branch well, wherein, horizontal branch well includes the first horizontal branch well E being positioned at the upper area of colliery layer,
And using the aspect of 1/3rd with the thickness that distance is colliery layer of the end face of colliery layer as the axis of the first horizontal branch well E
The plane at place offers the first horizontal branch well E, offers the horizontal branch well connected with horizontal well B and also includes: in following colliery
Offer in digging district, tunnel F between the second horizontal branch well D, straight well A and following coal mine gallery digging district F by the second level
Multilateral Wells D connects indirectly.Owing to the gas in colliery is concentrated mainly on upper area, so upper in the layer of colliery
Portion offers horizontal branch well in region, it is possible to being gone out by the most of gas exhaust in the layer of colliery, pump drainage effect is the most thorough
The end, pump drainage efficiency is high.Existing drawing-off gas well due to horizontal well and the restriction offering position of horizontal branch well,
The problem that blocking, water seal and straight well can not reuse easily occurs.
It practice, the three of the thickness that distance is colliery layer of the end face of the axis of the first horizontal branch well E and colliery layer
/ mono-.It is to say, in the first horizontal branch well E is arranged in colliery layer and distance colliery layer end face away from
In the aspect of 1/3rd of the thickness for colliery layer, it is possible to the more effectively gas in the layer of pump drainage colliery.
It addition, horizontal branch well also includes the second horizontal branch well D being positioned at following coal mine gallery digging district F.Will
Multilateral Wells is laid in following digging tunnel, is conducive to the gas in pre-pump drainage digging tunnel, fall before mine excavation
Gas stock in low following digging tunnel, improves safety coefficient.
It practice, indirectly connected by the second horizontal branch well D between straight well A and following coal mine gallery digging district F
Logical.In prior art, generally straight well is crept into and dig in district F with following coal mine gallery, when following coal mine gallery
After digging district F is dug out, straight well A and following coal mine gallery digging district F is formed for the relation directly connected,
So, straight well A just constitutes a branch in mine excavation tunnel, along with the carrying out of mine excavation, due to ore bed
Movement, straight well A will be destroyed, it is impossible to be further continued for use.And in this application straight well A is designed to not
Carry out the form of coal mine gallery digging district F indirect communication, be i.e. do not connect between straight well A and following coal mine gallery digging district F
Logical, straight well A can be made to be in the state independent of mine excavation tunnel, it is to avoid straight well A is destroyed, and makes straight well A
Can be also used for the Multipurpose well of later stage tunnel pump drainage.Actual creep into straight well A when, as long as by straight well A bore
Enter and there is a segment distance between following coal mine gallery digging district F.
Affected in order to avoid straight well A is moved by ore bed in the mining process of colliery and be destroyed, offered straight well A
, also include: move angle according to the rock of following coal mine gallery digging district F and determine that straight well A's offers position before, so that directly
Well A is moved at residing ore bed and keeps afterwards connecting with horizontal well B.Utilize rock to move angle and determine the position of straight well A
Put, it is to avoid the ore bed moved destroys, be soluble to those skilled in the art.Problematically, this
The Normal practice in field is only to utilize straight well A when digging and carrying out pre-drawing-off gas between coal mine gallery, and in colliery
After digging or the most again creep into a bite straight well or utilize horizontal well B to realize the drawing-off gas in later stage.The application
In, change existing conventional method, straight well A is designed to can mine excavation early stage and later stage can by with
Carry out the well of drawing-off gas, improve the utilization rate of straight well A, it is to avoid repeatedly drill through the program of multiple straight well, improve colliery
Gas exhaust method.
The above-mentioned process offering the horizontal well B connected with described straight well A, including: first, determine colliery to be dug
Ore bed bearing of trend；Afterwards, open against ore bed tendency along the vertical direction moved towards with ore bed in the bottom of ore bed
If horizontal well B.Being arranged on bottom ore bed by horizontal well B, horizontal branch well also forms state diagonally downward, so
Can be advantageously in drawing-off gas and elimination water blocking.
According to another aspect of the present invention, a kind of colliery drawing-off gas well, the shape of this drawing-off gas well are additionally provided
One-tenth process is crept into according to above-mentioned boring method and is formed, and therefore, this drawing-off gas well includes: straight well A；Horizontal well B,
Connect with straight well A；Horizontal branch well, connects with horizontal well B, and horizontal branch well includes the top being positioned at colliery layer
The first horizontal branch well E in region.Further, the end face of the axis of the first horizontal branch well E and described colliery layer
/ 3rd of the thickness that distance is described colliery layer.Horizontal branch well also includes being positioned at following coal mine gallery digging district F
In and with the second described horizontal branch well D.By described second between straight well A and following coal mine gallery digging district F
Horizontal branch well D connects indirectly.The bearing of trend of horizontal well B is parallel with described ore bed bearing of trend.
In order to make it easy to understand, combine the boring method that Fig. 1 illustrates that the present invention provides.
First, according to calculating, determine the distance of straight well A and following coal mine gallery digging F place, district aspect；
Second, use big drill bit expanded hole, the cavity connected with straight well A as horizontal well B at colliery layer, and count
Calculate shaft bottom coordinate；
3rd, choose the well location of horizontal well B according to surface condition, use Technology of Directional Drilling and rotary steering technology
Horizontal well B is made to connect with straight well A；
4th, horizontal well B are so that inversely in ore bed tendency, (being perpendicular to the direction of seam strike, ore bed is inclined to by upper inclination
Downwards, horizontal well B tilts upward and creeps into) extend and creep into, after arriving predetermined length, draw back directional tool and carry out level
The drilling well of Multilateral Wells E；
5th, horizontal branch well B are at following coal mine gallery digging district F, parallel digging district horizontal drilling；
6th, under coal bed top, in the layer of colliery, at colliery layer thickness three/mono-, carry out horizontal branch well E
Creep into.
Below, the brightest above-mentioned boring method:
First, on ground, rock according to following coal mine gallery digging district F moves angle and determines the position of straight well A, bores and reaches coal seam
Lower more than 10m, as extraction sediment district；
Second, under enter measuring instrument and carry out the well track parameter measurement of straight well A, calculate well coordinate；
3rd, in straight well A under enter pillar；
4th, then under enter diameter more than the reaming bit of 500mm in colliery layer reaming, as horizontal well B and straight well
The cavity of A connection；
5th, according to ore bed situation and the requirement of horizontal well B, determine horizontal well B；
6th, horizontal well B directional inclination is connected with straight well A, the horizontal segment reverse ore bed tendency of horizontal well B is prolonged
Prepare after reaching design length (this design length needs and the ability of ground drilling equipment determines) according to colliery owner
Start horizontal branch well；
7th, first implement the second horizontal branch well D, the second horizontal branch well D and be positioned at following coal mine gallery digging district F
In；
8th, then draw back the first horizontal branch well E, the first horizontal branch well E that drilling tool implements in colliery layer and be positioned at coal
In ore bed away from colliery layer end face distance for colliery layer thickness 1/3rd at.
9th, the rest may be inferred, completes all horizontal branch wells always, thus reaches effective drawing-off gas.
The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for this area
For technical staff, the present invention can have various modifications and variations.All within the spirit and principles in the present invention, institute
Any modification, equivalent substitution and improvement etc. made, should be included within the scope of the present invention.
Claims (7)
1. a colliery drawing-off gas well, it is characterised in that including:
Straight well (A)；
Horizontal well (B), the inverse ore bed of described horizontal well (B) is inclined to, and connects with described straight well (A)；
Horizontal branch well, connects with described horizontal well (B), and described horizontal branch well includes the upper area being positioned at colliery layer
The distance of interior the first horizontal branch well (E), the axis of described first horizontal branch well (E) and the end face of described colliery layer
For the thickness of described colliery layer 1/3rd；
Described horizontal branch well also includes the second horizontal branch well (D) being positioned at following coal mine gallery digging district (F), institute
State between straight well (A) and described following coal mine gallery digging district (F) indirect by described second horizontal branch well (D)
Ground connection.
Colliery the most according to claim 1 drawing-off gas well, it is characterised in that
Described horizontal well (B) is positioned at the bottom of described colliery layer and extends along the vertical direction moved towards with described colliery layer.
Colliery the most according to claim 1 and 2 drawing-off gas well, it is characterised in that
Described horizontal branch well extends along the axially in parallel direction with following coal mine gallery.
4. the boring method of a colliery drawing-off gas well, it is characterised in that including:
Offer straight well (A)；
Offer inverse ore bed tendency horizontal well (B) connected with described straight well (A)；
Offer the horizontal branch well connected with described horizontal well (B),
Wherein,
Described offer the horizontal branch well connected with described horizontal well (B), including: offer the upper area being positioned at colliery layer
In the first horizontal branch well (E), and by three points of thickness that the distance with the end face of described colliery layer is described colliery layer
One of aspect offer described first horizontal branch well as the plane at the axis place of described first horizontal branch well (E)
(E)；
The described horizontal branch well connected with described horizontal well (B) of offering also includes: following coal mine gallery digging district (F)
Inside offer the second horizontal branch well (D), pass through between described straight well (A) and described following coal mine gallery digging district (F)
Described second horizontal branch well (D) connects indirectly.
Boring method the most according to claim 4, it is characterised in that described in offer straight well (A) before, also include:
What the rock according to following coal mine gallery digging district (F) moved that angle determines described straight well (A) offers position, so that described
Straight well (A) is moved at residing ore bed and keeps afterwards connecting with described horizontal well (B).
Boring method the most according to claim 4, it is characterised in that described in offer the horizontal well connected with described straight well (A)
(B), including:
Determine the ore bed tendency in colliery to be dug；
Described horizontal well (B) is offered along the vertical direction moved towards with described colliery layer in the bottom of colliery layer.
Boring method the most according to claim 4, it is characterised in that
The horizontal branch well connected with described horizontal well (B) is offered along the axially in parallel direction digging tunnel with future.
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| CN104963714A (en) * | 2015-04-30 | 2015-10-07 | 山西蓝焰煤层气集团有限责任公司 | Standing air shaft safe coal-uncovering technology of high gassy mine |
| CN104989366A (en) * | 2015-08-03 | 2015-10-21 | 中国神华能源股份有限公司 | Coal mine well and construction method thereof |
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| CN109441525A (en) * | 2018-11-12 | 2019-03-08 | 中国神华能源股份有限公司 | The method of pump drainage coal bed gas |
| CN110306934B (en) * | 2019-07-02 | 2021-03-19 | 中煤科工集团西安研究院有限公司 | Construction method for large-diameter high-position directional long drill hole of double-branch top plate |
| RU2749707C1 (en) * | 2020-12-14 | 2021-06-16 | федеральное государственное бюджетное образовательное учреждение высшего образования «Санкт-Петербургский горный университет» | Method for degassing of overworked adjacent seams |
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