CN110359879A - A kind of abandoned well method for blocking - Google Patents
A kind of abandoned well method for blocking Download PDFInfo
- Publication number
- CN110359879A CN110359879A CN201810252783.0A CN201810252783A CN110359879A CN 110359879 A CN110359879 A CN 110359879A CN 201810252783 A CN201810252783 A CN 201810252783A CN 110359879 A CN110359879 A CN 110359879A
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- Prior art keywords
- abandoned well
- parts
- slurry
- weight
- well
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Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/13—Methods or devices for cementing, for plugging holes, crevices, or the like
- E21B33/134—Bridging plugs
-
- 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
- E21F17/16—Modification of mine passages or chambers for storage purposes, especially for liquids or gases
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention discloses a kind of abandoned well method for blocking, belong to well workover field.The method for blocking includes: will be in oil pipe tripping in abandoned well at predetermined depth.By oil pipe to the protection plug slurry of injection predetermined amount above the cement plug of the abandoned well, and protection plug slurry is staticly settled, obtains protection plug, complete the closure to abandoned well.Protection plug slurry is prepared by the following method: the blanc fixe of the water of 980-1020 parts by weight, the bentonite of 40-60 parts by weight, the sodium carbonate of 2-3 parts by weight, 1000-1050 parts by weight is mixed; and stir the first preset time; hydration swelling after mixing bentonite, sodium carbonate, blanc fixe with water forms mixture slurry.The diluent of 10-20 parts by weight is added into mixture slurry and stirs the second preset time, forms protection plug slurry.Even if producing gap between abandoned well method for blocking cement plug provided by the invention and the borehole wall of abandoned well, it can also be leaked to avoid the natural gas in abandoned well, improve the plugging effect to abandoned well.
Description
Technical field
The present invention relates to well workover technology field, in particular to a kind of abandoned well method for blocking.
Background technique
Gas storage is a kind of artificial oil gas that the next natural gas of long distance pipeline conveying is refilled the underground space and is formed
Hiding, in order to avoid natural gas leaking occurs for abandoned well unserviceable in gas storage, to influence the safety work of gas storage, palpus
Abandoned well is permanently blocked.
The relevant technologies block abandoned well unserviceable in gas storage using cement plug.Specifically, to wait block
Abandoned well in inject predetermined amount cement slurry can form cement plug after the cement slurry solidify in exhaust gas well, with realization
Closure to abandoned well.
Inventor find the relevant technologies the prior art has at least the following problems:
Cement plug plugged and abandoned well for a period of time after, be easy under the action of strata pressure between the borehole wall of abandoned well
Gap is generated, to cause natural gas leaking, leaves hidden danger for the subsequent safety work of gas storage.
Summary of the invention
The embodiment of the invention provides a kind of abandoned well method for blocking, can solve above-mentioned technical problem.Specific technical solution
It is as follows:
The embodiment of the invention provides a kind of abandoned well method for blocking, the method for blocking includes: to discard oil pipe tripping in
In well at predetermined depth；
By the oil pipe to the protection plug slurry of injection predetermined amount above the cement plug of the abandoned well, and make the guarantor
Shield plug slurry staticly settles, and obtains protection plug, completes the closure to the abandoned well；
The protection plug slurry is prepared by the following method:
By the water of 980-1020 parts by weight, the bentonite of 40-60 parts by weight, the sodium carbonate of 2-3 parts by weight, 1000-1050
The blanc fixe of parts by weight mixes, and stirs the first preset time, makes the bentonite, the sodium carbonate, the blanc fixe
Hydration swelling after mixing with the water forms mixture slurry；
The diluent of 10-20 parts by weight is added into the mixture slurry and stirs the second preset time, forms the guarantor
Shield plug slurry.
In a kind of possible design, first preset time is 25min-35min.
In a kind of possible design, second preset time is 10min-15min.
In a kind of possible design, the predetermined depth is 8m-15m above the cement plug.
In a kind of possible design, in by abandoned well described in the oil pipe tripping at predetermined depth after, to described useless
Abandoned well carries out well-flushing.
In a kind of possible design, in the protection plug for injecting predetermined amount into the abandoned well by the oil pipe
After slurry, the simple to install well head on the abandoned well.
Technical solution provided in an embodiment of the present invention has the benefit that
Abandoned well method for blocking provided in an embodiment of the present invention protects plug slurry by preparation, and by the protection plug slurry
It is injected into above the cement plug of abandoned well and staticly settles, obtain protection plug, to realize the closure to abandoned well.In preparation protection plug
During slurry, by using sodium carbonate, bentonite, blanc fixe and the mixed hydration swelling ability of water can be improved.
By using diluent, bentonite and blanc fixe in mixture slurry can be made to precipitate, and as the growth of time exists
It is constantly compacted in abandoned well, forms protection plug, the abandoned well above cement plug is blocked completely.As it can be seen that the embodiment of the present invention mentions
The abandoned well method for blocking of confession is to be blocked again on the basis of cement plug to abandoned well, even if cement plug and discarded
Gap is produced between the borehole wall of well, also be can use protection and is filled in plugged and abandoned well, the natural gas in abandoned well is avoided to let out
Leakage, improves the plugging effect to abandoned well, ensure that the subsequent safety work of gas storage.
Specific embodiment
Unless otherwise defined, all technical terms used in the embodiment of the present invention all have usual with those skilled in the art
The identical meaning understood.It to make the object, technical solutions and advantages of the present invention clearer, below will be to embodiment party of the present invention
Formula is described in further detail.
The embodiment of the invention provides a kind of abandoned well method for blocking, which includes: by oil pipe tripping in abandoned well
At interior predetermined depth.
By oil pipe to the protection plug slurry of injection predetermined amount above the cement plug of abandoned well, and stand protection plug slurry
Precipitating obtains protection plug, completes the closure to abandoned well.
Protection plug slurry is prepared by the following method:
By the water of 980-1020 parts by weight, the bentonite of 40-60 parts by weight, the sodium carbonate of 2-3 parts by weight, 1000-1050
The blanc fixe of parts by weight mixes, and stirs the first preset time, water after mixing bentonite, sodium carbonate, blanc fixe with water
Change expansion, forms mixture slurry.
The diluent of 10-20 parts by weight is added into mixture slurry and stirs the second preset time, forms protection plug slurry.
In " staticly settling protection plug slurry, to obtain protection plug ", bentonite and blanc fixe in protection plug slurry
It can be separated from water, and precipitate, and be constantly compacted with the extension of time of repose under the action of diluent, and then be formed
Protection plug.
Abandoned well method for blocking provided in an embodiment of the present invention protects plug slurry by preparation, and by the protection plug slurry
It is injected into above the cement plug of abandoned well and staticly settles, obtain protection plug, to realize the closure to abandoned well.In preparation protection plug
During slurry, by using sodium carbonate, bentonite, blanc fixe and the mixed hydration swelling ability of water can be improved.
By using diluent, bentonite and blanc fixe in mixture slurry can be made to precipitate, and as the growth of time exists
It is constantly compacted in abandoned well, forms protection plug, the abandoned well above cement plug is blocked completely.As it can be seen that the embodiment of the present invention mentions
The abandoned well method for blocking of confession is to be blocked again on the basis of cement plug to abandoned well, even if cement plug and discarded
Gap is produced between the borehole wall of well, also be can use protection and is filled in plugged and abandoned well, the natural gas in abandoned well is avoided to let out
Leakage, improves the plugging effect to abandoned well, ensure that the subsequent safety work of gas storage.
Wherein, " predetermined amount " is it is to be understood that abandoned well is filled required amount by protection plug slurry.
Bentonitic parts by weight are 40-60 parts, such as 41 parts, 43 parts, 45 parts, 47 parts, 50 parts；The parts by weight of sodium carbonate are
2-3 parts, such as 2 parts, 3 parts；The parts by weight of blanc fixe be 1000-1050, such as 1005 parts, 1010 parts, 1015 parts, 1020 parts,
1025 parts etc.；The parts by weight of diluent are 10-20 parts, such as 11 parts, 13 parts, 15 parts, 17 parts, 19 parts；The parts by weight of water are
980-1020 parts, such as 990 parts, 1000 parts, 1010 parts.By bentonite, sodium carbonate, barite that above-mentioned parts by weight are arranged
Powder, diluent, water, it is ensured that finally formed protection plug is finer and close compared to cement plug, to the plugging effect of abandoned well
More preferably.
Water, bentonite, sodium carbonate, blanc fixe, diluent mixing process can be with carrying out in liquid pool, this is matched
The structure of liquid pool can be a variety of, for example, it can be cylindrical structure, square structure etc., as long as guaranteeing that it can hold
Receive above-mentioned water, bentonite, sodium carbonate, blanc fixe, diluent.
In addition, protection plug slurry can be injected into abandoned well by way of direct circulation, i.e., protection plug slurry is from oil
Pipe is injected into abandoned well.Also, in order to improve the preparation speed of protection plug, it can use blender and above-mentioned stir twice
Mix operation.
In order to guarantee after bentonite, sodium carbonate, blanc fixe and water are mixed and stirred for can abundant hydration swelling, can will
First preset time is set as 25min-35min (such as 28min, 30min, 32min).
In order to which the mixture slurry for guaranteeing that diluent can be formed with water, bentonite, sodium carbonate, blanc fixe stirs evenly,
It can set the second preset time to 10min-15min (such as 10min, 11min, 12min).
Further, in order to guarantee that protection plug slurry can smoothly inject in the abandoned well above cement plug, while will not
Cement plug is damaged, above-mentioned predetermined depth can be set to 8m-15m (such as 8m, 10m, 12m) above cement plug, is i.e. oil pipe
Bottom end is located at 8m-15m above cement plug.
In order to realize the cleaning to sundries in abandoned well, protection plug is improved to the plugging effect of abandoned well, will be under oil pipe
After entering in abandoned well at predetermined depth, well-flushing is carried out to abandoned well.
The well-flushing it is understood that above-mentioned clean-out service can be positive, or anti-flushing well, as long as ensuring in abandoned well
Sundries can be smoothly discharged to well outer.And in order to guarantee well washing effect, it can be 2-4 weeks (such as 2 to abandoned well circulation well cleanup
Week, 3 weeks etc.).
Sundries is fallen into abandoned well in order to prevent, while the protection plug in abandoned well being avoided to be destroyed, natural gas is caused to be let out
Leakage.After injecting the protection plug slurry of predetermined amount into abandoned well by oil pipe, the simple to install well head on abandoned well.
Wherein, simple wellhead is common for this field, and those skilled in the art can be obtained by commercially available, and citing comes
It says, can be the simple wellhead that the petrolem machinery factory Funing Zhen Ya produces and sells.
Hereinafter the present invention will be further described through by specific embodiment.
In following specific embodiments, condition person is not specified in related operation, according to normal conditions or manufacturer
It is recommended that condition carry out.It is raw materials used production firm is not specified and specification person be can be with conventional products that are commercially available.
Embodiment 1
A kind of abandoned well method for blocking is present embodiments provided, which includes: by the water of oil pipe tripping in abandoned well
Above the bod at 8m.
It uses clear water circulation well cleanup 2 weeks.
By the water of 980 parts by weight, the bentonite of 40 parts by weight, the sodium carbonate of 2 parts by weight, 1000 parts by weight blanc fixe
Mixing, and 25min is stirred, hydration swelling after mixing bentonite, sodium carbonate, blanc fixe with water forms mixture slurry.
The diluent of 10 parts by weight is added into the mixture slurry and stirs 10min, forms protection plug slurry.
Protection plug slurry is filled to the cement plug top of abandoned well by oil pipe, and staticly settles protection plug slurry, is obtained
It is filled in protection, completes the closure to abandoned well.
The abandoned well method for blocking that the embodiment 1 provides can block the abandoned well above cement plug completely.As it can be seen that this
Inventive embodiments provide abandoned well method for blocking be abandoned well is blocked again on the basis of cement plug, even if
Gap is produced between cement plug and the borehole wall of abandoned well, also be can use protection and is filled in plugged and abandoned well, avoids in abandoned well
Natural gas leaks, and improves the plugging effect to abandoned well, ensure that the subsequent safety work of gas storage.
Embodiment 2
A kind of abandoned well method for blocking is present embodiments provided, which includes: by the water of oil pipe tripping in abandoned well
Above the bod at 10m.
It uses clear water circulation well cleanup 2 weeks.
The weight of the water of 1000 parts by weight, the bentonite of 50 parts by weight, the sodium carbonate of 2.5 parts by weight, 1025 parts by weight is brilliant
Mountain flour mixing, and 30min is stirred, hydration swelling after mixing bentonite, sodium carbonate, blanc fixe with water forms mixture slurry.
The diluent of 15 parts by weight is added into the mixture slurry and stirs 12min, forms protection plug slurry.
Protection plug slurry is filled to the cement plug top of abandoned well by oil pipe, and staticly settles protection plug slurry, is obtained
It is filled in protection, completes the closure to abandoned well.
The abandoned well method for blocking that the embodiment 2 provides can block the abandoned well above cement plug completely.As it can be seen that this
Inventive embodiments provide abandoned well method for blocking be abandoned well is blocked again on the basis of cement plug, even if
Gap is produced between cement plug and the borehole wall of abandoned well, also be can use protection and is filled in plugged and abandoned well, avoids in abandoned well
Natural gas leaks, and improves the plugging effect to abandoned well, ensure that the subsequent safety work of gas storage.
Embodiment 3
A kind of abandoned well method for blocking is present embodiments provided, which includes: by the water of oil pipe tripping in abandoned well
Above the bod at 12m.
It uses clear water circulation well cleanup 2 weeks.
By the water of 1020 parts by weight, the bentonite of 60 parts by weight, the sodium carbonate of 3 parts by weight, 1050 parts by weight barite
Powder mixing, and 35min is stirred, hydration swelling after mixing bentonite, sodium carbonate, blanc fixe with water forms mixture slurry.
The diluent of 20 parts by weight is added into the mixture slurry and stirs 15min, forms protection plug slurry.
Protection plug slurry is filled to the cement plug top of abandoned well by oil pipe, and staticly settles protection plug slurry, is obtained
It is filled in protection, completes the closure to abandoned well.
The abandoned well method for blocking that the embodiment 3 provides can block the abandoned well above cement plug completely.As it can be seen that this
Inventive embodiments provide abandoned well method for blocking be abandoned well is blocked again on the basis of cement plug, even if
Gap is produced between cement plug and the borehole wall of abandoned well, also be can use protection and is filled in plugged and abandoned well, avoids in abandoned well
Natural gas leaks, and improves the plugging effect to abandoned well, ensure that the subsequent safety work of gas storage.
The foregoing is merely presently preferred embodiments of the present invention, the protection scope being not intended to limit the invention, all in this hair
Within bright spirit and principle, any modification, equivalent replacement, improvement and so on should be included in protection scope of the present invention
Within.
Claims (6)
1. a kind of abandoned well method for blocking, which is characterized in that the method for blocking includes: that will preset deeply in oil pipe tripping in abandoned well
At degree；
By the oil pipe to the protection plug slurry of injection predetermined amount above the cement plug of the abandoned well, and fill in the protection
Slurry staticly settles, and obtains protection plug, completes the closure to the abandoned well；
The protection plug slurry is prepared by the following method:
By the water of 980-1020 parts by weight, the bentonite of 40-60 parts by weight, the sodium carbonate of 2-3 parts by weight, 1000-1050 weight
The blanc fixe mixing of part, and the first preset time is stirred, make the bentonite, the sodium carbonate, the blanc fixe and institute
Hydration swelling after water mixes is stated, mixture slurry is formed；
The diluent of 10-20 parts by weight is added into the mixture slurry and stirs the second preset time, forms the protection plug
Slurry.
2. method for blocking according to claim 1, which is characterized in that first preset time is 25min-35min.
3. method for blocking according to claim 1, which is characterized in that second preset time is 10min-15min.
4. method for blocking according to claim 1, which is characterized in that the predetermined depth is 8m- above the cement plug
15m。
5. method for blocking according to claim 1, which is characterized in that will preset in abandoned well described in the oil pipe tripping in
After depth, well-flushing is carried out to the abandoned well.
6. method for blocking according to claim 1, which is characterized in that passing through cement of the oil pipe to the abandoned well
After the protection plug slurry of the predetermined amount of side's injection beyond the Great Wall, the simple to install well head on the abandoned well.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810252783.0A CN110359879B (en) | 2018-03-26 | 2018-03-26 | Abandoned well plugging method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810252783.0A CN110359879B (en) | 2018-03-26 | 2018-03-26 | Abandoned well plugging method |
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| Publication Number | Publication Date |
|---|---|
| CN110359879A true CN110359879A (en) | 2019-10-22 |
| CN110359879B CN110359879B (en) | 2021-11-02 |
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ID=68212203
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810252783.0A Active CN110359879B (en) | 2018-03-26 | 2018-03-26 | Abandoned well plugging method |
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| CN (1) | CN110359879B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113586004A (en) * | 2020-04-30 | 2021-11-02 | 中国石油天然气股份有限公司 | Method for plugging waste well of gas storage |
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| CN113586004A (en) * | 2020-04-30 | 2021-11-02 | 中国石油天然气股份有限公司 | Method for plugging waste well of gas storage |
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| CN110359879B (en) | 2021-11-02 |
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