CN108331560A - A kind of coal bed gas surface well pumping method of minery containing water flooding - Google Patents
A kind of coal bed gas surface well pumping method of minery containing water flooding Download PDFInfo
- Publication number
- CN108331560A CN108331560A CN201810085715.XA CN201810085715A CN108331560A CN 108331560 A CN108331560 A CN 108331560A CN 201810085715 A CN201810085715 A CN 201810085715A CN 108331560 A CN108331560 A CN 108331560A
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- casing
- well
- open
- bed gas
- minery
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- 239000003245 coal Substances 0.000 title claims abstract description 36
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 title claims abstract description 12
- 238000005086 pumping Methods 0.000 title claims abstract description 9
- 230000001681 protective effect Effects 0.000 claims abstract description 10
- 239000000725 suspension Substances 0.000 claims description 11
- 238000005553 drilling Methods 0.000 claims description 7
- 238000005065 mining Methods 0.000 claims description 7
- 239000011435 rock Substances 0.000 claims description 5
- 239000004568 cement Substances 0.000 claims description 3
- 238000009434 installation Methods 0.000 claims description 3
- 238000000605 extraction Methods 0.000 abstract description 10
- 239000004576 sand Substances 0.000 abstract description 8
- 230000006378 damage Effects 0.000 abstract description 5
- 229910000831 Steel Inorganic materials 0.000 abstract description 3
- 239000011148 porous material Substances 0.000 abstract description 3
- 239000010959 steel Substances 0.000 abstract description 3
- 230000000694 effects Effects 0.000 description 3
- 230000000903 blocking effect Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/006—Production of coal-bed methane
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/10—Wear protectors; Centralising devices, e.g. stabilisers
- E21B17/1078—Stabilisers or centralisers for casing, tubing or drill pipes
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/02—Subsoil filtering
- E21B43/08—Screens or liners
- E21B43/086—Screens with preformed openings, e.g. slotted liners
Landscapes
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Fluid Mechanics (AREA)
- Environmental & Geological Engineering (AREA)
- Physics & Mathematics (AREA)
- Geochemistry & Mineralogy (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Dispersion Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Earth Drilling (AREA)
Abstract
Coal bed gas extraction of the present invention field, disclose a kind of coal bed gas surface well pumping method of minery containing water flooding, surface well is arranged to three and driven a well body structure by this method, increase protective device on casing by being opened two, even if two, which open casing, there is movement and deformation or fracture, increased protective device make two to open casing is more together to be protected, to which two destructions for driving a well body be effectively relieved；The steel strainer that sleeve bottom is opened positioned at two ensure that sand grains that stratum water burst carries does not enter three and drives a well body, and the three three-stage designs for opening casing had both prevented the sand grains that stratum water burst carries into shaft bottom or borehole wall sieve pore, the structural stability that surface well can be enhanced again, has preferably ensured extracting result.
Description
Technical field
The invention belongs to coal bed gas extraction fields, and in particular to a kind of coal bed gas surface well of minery containing water flooding extraction side
Method.
Background technology
The technology of existing minery coal bed gas (gas) surface well can preferably solve distressed zone coal bed gas (gas), including
The coal bed gas (gas) for (adopting dynamic stability area) after (mining influence area) and coal back production in coal back production；But for aquifer water-bearing stratum
For, minery coal bed gas surface well extracting result can be impacted.Main reason is that：Surface well will produce change after adopting disturbance
Shape or even slight damage, but gas channel is still unimpeded, and due to the presence in water-bearing layer, water-bearing layer will take blowout and enter well set
It is interior, certain blocking is generated to the mining induced fissure in shaft bottom and the borehole wall, to influence extracting result.Preferable be directed to there is no to contain at present
The method of water stratum minery coal bed gas surface well extraction.
Invention content
In view of this, the purpose of the present invention is to provide a kind of coal bed gas surface well pumping method of minery containing water flooding,
To enhance surface well structural stability, prevent the sand grains that stratum water burst carries into shaft bottom or borehole wall sieve pore.
In order to achieve the above objectives, the present invention provides the following technical solutions：A kind of coal bed gas surface well of minery containing water flooding
Pumping method, surface well are arranged to three and drive a well body structure, mainly include the following steps that：
(1) one drives a well body from earth drilling to the following certain distance of basement rock, after install one and open casing and cement the well；
(2) two bodies that drive a well are crept into coal mining overlying strata fissure zone top edge, are installed two and are opened casing and make two to open cannula tip height
Go out earth's surface certain distance；It opens in two corresponding to the violent position section of strata deformation and installs protective device on casing, it is laggard
Row two opens casing cementing；
(3) installation suspension interstage sleeve at casing shoe is opened two；
(4) three bodies that drive a well drill coal seam to following certain distance, are installed in earth's surface to the above certain distance in coal seam is interregional
Three open casing；Described three, which open casing, is from top to bottom followed successively by " sieve tube segment-casing section-sieve tube segment ", the sieve tube segment of middle and lower part
It drives a well body bottom surface to hereinafter, the two body bottom surface above sections that drive a well are then " sieve tube segment-casing section " since two；
(5) it is opened three and hanging sleeve and strainer is installed below casing, strainer is located above hanging sleeve；Three, which open cannula tip, passes through fixation
Plate is opened casing with two and is mutually fixed, and lower section then hangs on the two suspension interstage sleeves for opening casing shoe by the hanging sleeve correspondence being disposed thereon
On.
Further, a drilling distance for driving a well body is a in the step (1), and a is basement rock or less 10m；The step
(2) two open cannula tip and are higher by earth's surface 0.3m in；A drilling distance for driving a well body is d in the step (4), and the d is from earth's surface
It is drilled into coal seam or less 10m-15m.
Further, the suspension interstage sleeve in the step (3) is equipped with multistage and arranges up and down.
Further, the strainer in the step (5) has two layers and arranges up and down.
The beneficial effects of the present invention are：The surface well is three to drive a well body structure, wherein two open on casing and increase anti-
Protection unit, even if two open casing and movement and deformation or fracture occur, increased protective device make two to open casing is more to be protected together, energy
Two destructions for driving a well body are effectively relieved；The steel strainer of sleeve bottom is opened positioned at two can ensure the sand grains of stratum water burst carrying not
It drives a well body into three, and the three three-stage designs for opening casing had both prevented the sand grains that stratum water burst carries to be sieved into shaft bottom or the borehole wall
Hole, and the structural stability of surface well can be enhanced, preferably ensure extracting result.
Description of the drawings
In order to keep the purpose of the present invention, technical solution and advantageous effect clearer, the present invention provides following attached drawing and carries out
Explanation：
Fig. 1 is the schematic diagram of the present invention.
Specific implementation mode
Below in conjunction with attached drawing, the preferred embodiment of the present invention is described in detail.
To solve the problems, such as the extraction of the coal bed gas surface well of minery containing water flooding, as shown, the present embodiment is by surface well
It is arranged to three to drive a well body structure, mainly includes the following steps that：
(1) one drives a well body 10m below from earth drilling to basement rock, after install one and open casing 1 and cement the well；
(2) two bodies that drive a well are crept into coal mining overlying strata fissure zone top edge, are installed two and are opened casing 2 and make two to open 2 top of casing
It is higher by 0.2~0.4m of earth's surface；It opens in two corresponding to the violent position section of strata deformation and installs protective device on casing, after
It carries out two and opens casing cementing；It two opens cannula tip herein and is higher by the setting of earth's surface ground scene extraction system can be enable preferably to pacify
If to facilitate extraction；And the protective device opened on casing two is set can open casing for two and certain deformation space is provided, make
Two open casing can certain stretcher strain in tension in the axial direction, to not damage well bore, i.e., at " strata deformation is violent "
In the case of open casing to two and play a certain protective role.
(3) 2 bottom end of casing installation suspension interstage sleeve 3 is opened two；
(4) three bodies that drive a well drill coal seam to following 10~15m, and three are installed to the above certain distance in coal seam is interregional in earth's surface
Open casing 4；Described three, which open casing, is from top to bottom followed successively by " sieve tube segment-casing section-sieve tube segment ", the sieve tube segment of middle and lower part from
Two drive a well body bottom surface start to hereinafter, top sieve tube segment since earth's surface to following certain distance, middle part is then casing section；Tool
Body, it opens casing 4 by three and is arranged to sieve tube segment-casing section-sieve tube segment form, superposed sieve tube segment is opened for extraction two
Drive a well the coal bed gas that overlying strata crack comes out between body with three, the casing section at middle part for preventing water or sand from blocking extraction channel, and
The sieve tube segment of lower part is then used for the coal bed gas of extraction coal seam and coal seam top gap region；It should be noted that this three opens casing
Bottom end is arranged in coal seam top certain distance, is to prevent the later stage from mining to ensure that screen casing does not influence seam mining and be difficult to handle.
(5) it is opened three and hanging sleeve and strainer 5 is installed below casing 4, strainer 5 is located above hanging sleeve；Three, which open cannula tip, passes through
Fixed plate 6 is opened casing with two and is mutually fixed, and lower section then hangs on two by the hanging sleeve correspondence being disposed thereon and opens the outstanding of casing shoe
It puts into gear on set 3, realizes suspension completion.For fixed plate 6 herein there are two effect, one is to make three to open casing placed in the middle as possible, another
It is a, it is to try to sealing two and opens the gap to drive a well between body with three, prevent gas leakage to earth's surface.Two open the suspension of casing shoe
Interstage sleeve 3 is to be welded on two to open cross interstage sleeve on the inside of casing, and three pairs for opening casing are set on the matched extension of suspension interstage sleeve
Position is answered, is coordinated by the two, ensure that two open the connection opened with three.
Suspension interstage sleeve 3 in step (3) can be equipped with multistage, and arrangement up and down；At least two layers of strainer 5 in step (5)
And it arranges up and down.The steel strainer of sleeve bottom is opened positioned at two can ensure that the sand grains of stratum water burst carrying does not enter three and drives a well
Body, the three of full well bore, which opens casing then, can enhance the stable structure of surface well.
The surface well is three to drive a well body structure, wherein two open on casing and increase protective device, two opens casing at this time and has
The effect of overlying strata movement is resisted, even if two open casing and movement and deformation or fracture occur, increased protective device makes two, and to open casing more
It protects together, two destructions for driving a well body can be effectively relieved, therefore increase ground structure stability or connectivity.And three open casing
Three-stage design then prevent the sand grains that stratum water burst carries into shaft bottom or borehole wall sieve pore, therefore the increase of the casing can be preferably
Ensure extracting result.
Finally illustrate, preferred embodiment above is merely illustrative of the technical solution of the present invention and unrestricted, although logical
It crosses above preferred embodiment the present invention is described in detail, however, those skilled in the art should understand that, can be
Various changes are made to it in form and in details, without departing from claims of the present invention limited range.
Claims (4)
1. a kind of coal bed gas surface well pumping method of minery containing water flooding, it is characterised in that：Surface well is arranged to three and drives a well body
Structure mainly includes the following steps that：
(1) one drives a well body from earth drilling to the following certain distance of basement rock, after install one and open casing and cement the well；
(2) two bodies that drive a well are crept into coal mining overlying strata fissure zone top edge, are installed two and are opened casing and make two to open cannula tip and are higher by ground
Table certain distance；It opens in two corresponding to the violent position section of strata deformation and installs protective device on casing, carry out two afterwards
Open casing cementing；
(3) installation suspension interstage sleeve at casing shoe is opened two；
(4) three bodies that drive a well drill coal seam to following certain distance, install three to the above certain distance in coal seam is interregional in earth's surface and open
Casing；Described three, which open casing, is from top to bottom followed successively by " sieve tube segment-casing section-sieve tube segment ", and the sieve tube segment of middle and lower part is from two
Drive a well body bottom surface start to hereinafter, two drive a well body bottom surface above section then be " sieve tube segment-casing section "；
(5) it is opened three and hanging sleeve and strainer is installed below casing, strainer is located above hanging sleeve；Three open cannula tip by fixed plate with
Two, which open casing, mutually fixes, and lower section then hangs on two by the hanging sleeve correspondence being disposed thereon and opens on the suspension interstage sleeve of casing shoe.
2. the coal bed gas of minery containing water flooding surface well pumping method according to claim 1, it is characterised in that：
A drilling distance for driving a well body is a in the step (1), and a is basement rock or less 10m；
Two open cannula tip and are higher by 0.2~0.4m of earth's surface in the step (2)；
A drilling distance for driving a well body is d in the step (4), and the d is drilled into coal seam or less 10m~15m from earth's surface.
3. the coal bed gas of minery containing water flooding surface well pumping method according to claim 1, it is characterised in that：The step
Suddenly the suspension interstage sleeve in (3) is equipped with multistage and arranges up and down.
4. the coal bed gas of minery containing water flooding surface well pumping method according to claim 1, it is characterised in that：The step
Suddenly the strainer in (5) has two layers and arranges up and down.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810085715.XA CN108331560B (en) | 2018-01-29 | 2018-01-29 | A kind of coal bed gas surface well pumping method of minery containing water flooding |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810085715.XA CN108331560B (en) | 2018-01-29 | 2018-01-29 | A kind of coal bed gas surface well pumping method of minery containing water flooding |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108331560A true CN108331560A (en) | 2018-07-27 |
| CN108331560B CN108331560B (en) | 2019-04-02 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201810085715.XA Active CN108331560B (en) | 2018-01-29 | 2018-01-29 | A kind of coal bed gas surface well pumping method of minery containing water flooding |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109630189A (en) * | 2018-12-12 | 2019-04-16 | 中煤科工集团重庆研究院有限公司 | The method of highly gassy mine minery surface well improvement coal working face gas |
| CN111075349A (en) * | 2019-12-20 | 2020-04-28 | 山西晋城无烟煤矿业集团有限责任公司 | Construction method of ground mining empty well suspension type well body structure |
| CN112796680A (en) * | 2021-01-04 | 2021-05-14 | 中煤科工集团重庆研究院有限公司 | Suspension installation method for protecting casing pipe of pre-pumping ground well to mining well |
| CN113863895A (en) * | 2021-04-30 | 2021-12-31 | 中国矿业大学 | Well body structure of oil and gas well penetrating through recoverable coal seam and construction method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109630189A (en) * | 2018-12-12 | 2019-04-16 | 中煤科工集团重庆研究院有限公司 | The method of highly gassy mine minery surface well improvement coal working face gas |
| CN111075349A (en) * | 2019-12-20 | 2020-04-28 | 山西晋城无烟煤矿业集团有限责任公司 | Construction method of ground mining empty well suspension type well body structure |
| CN111075349B (en) * | 2019-12-20 | 2021-08-27 | 山西晋城无烟煤矿业集团有限责任公司 | Construction method of ground mining empty well suspension type well body structure |
| CN112796680A (en) * | 2021-01-04 | 2021-05-14 | 中煤科工集团重庆研究院有限公司 | Suspension installation method for protecting casing pipe of pre-pumping ground well to mining well |
| CN112796680B (en) * | 2021-01-04 | 2022-05-03 | 中煤科工集团重庆研究院有限公司 | Suspension installation method for protecting casing pipe of pre-pumping ground well to mining well |
| CN113863895A (en) * | 2021-04-30 | 2021-12-31 | 中国矿业大学 | Well body structure of oil and gas well penetrating through recoverable coal seam and construction method |
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| CN108331560B (en) | 2019-04-02 |
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