CN109503762A - A kind of complete solvable high-intensitive chemical packer of green and preparation method thereof - Google Patents
A kind of complete solvable high-intensitive chemical packer of green and preparation method thereof Download PDFInfo
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- CN109503762A CN109503762A CN201811466563.4A CN201811466563A CN109503762A CN 109503762 A CN109503762 A CN 109503762A CN 201811466563 A CN201811466563 A CN 201811466563A CN 109503762 A CN109503762 A CN 109503762A
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- green
- packer
- chemical packer
- intensitive
- acrylic acid
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F226/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a single or double bond to nitrogen or by a heterocyclic ring containing nitrogen
- C08F226/06—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a single or double bond to nitrogen or by a heterocyclic ring containing nitrogen by a heterocyclic ring containing nitrogen
- C08F226/10—N-Vinyl-pyrrolidone
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Abstract
The invention discloses a kind of complete solvable high-intensitive chemical packers of green, cause polymerization under initiator effect by material acid, acrylic acid, n-vinyl pyrrolidone and are made.Each raw material component weight percent is as follows: lactic acid 15-20%, acrylic acid 10-15%, n-vinyl pyrrolidone 5-10%, distilled water 53-69%, initiator 0.02-0.05%.The preparation method is as follows: (1) distilled water is added into reaction vessel, it is passed through nitrogen displacement discharge air；(2) reaction vessel is added in lactic acid, acrylic acid, n-vinyl pyrrolidone, is stirring evenly and then adding into initiator, heating makes reacting liquid temperature rise to 120 DEG C, and constant temperature is stirred to react 30min, then adjusts pH value of reaction system 7-8；(3) continuing heating makes reaction solution system be warming up to 150 DEG C, and constant temperature is stirred to react 4h, then, purifies, dry, obtains head product.Chemical packer of the invention is completely dissolved in different temperatures fracturing fluid environment, noresidue solid, degradation rate 100%.
Description
Technical field
The present invention relates to technical field of petroleum extraction, and in particular to a kind of complete solvable high-intensitive chemical packer of green and its
Preparation method.
Background technique
Common stimulation technology be multistage separate stratum fracfturing technology, conventional staged fracturing be using mechanical packer into
Row separate zone stimulation, but this technology construction procedure is complicated, pressing crack construction is at high cost, especially multiple in ultra-deep, high temperature and pressure etc.
Under the conditions of miscellaneous hole condition, staged fracturing effect is also difficult to guarantee.In consideration of it, having developed breaking agent for chemical temporary-plugging, the pitching temporarily technologies such as stifled, the technology
It is poor using the fracture pressure between reservoir each position, staged fracturing is carried out to reservoir, crack is minimum, most fragile in stress first
It is generated in the substratum split, blocks oneself using sealing chemical packer and press off the eyelet and major fracture of interval, force on wellbore pressure
It rising, when reaching another grade of fracture pressure value, fracturing fluid presses off new crack along sub-clustering eyelet, and so on, repeatedly launch chemistry envelope
Every device, until every level-one successively presses off, raising longitudinal profile development degree increases the probability for linking up Accumulation zone.
The temporary stall of sealing, as a kind of effective fracturing reform means, refers in pressing crack construction by one to fracturing technique
The high-intensitive water-soluble granular chemical packer of secondary or multiple dispensing, particle chemical packer are formed in borehole and crack high permeability zone
Filter cake, the old crack of temporary plugging, the pressure improved in pit shaft promote horizontal payzone section other positions crack in conjunction with perforating technology
Unlatching, ultimately form a plurality of new crack, achieve the purpose that intensively to cut reservoir, effectively increase individual well transformation volume.
The temporary stall of sealing is to fracturing mechanism: since reservoir is generally there are heterogeneity, the reservoir properties of different reservoir section and
Fracture pressure is also different, usually first presses off the interval that reservoir properties are good, fracture pressure is low, then launches high-intensitive water-soluble
Property chemical packer block the crack of pressure break, and improve seam internal stress to force fluid to turn to, promote opening for secondary crack
It opens, achievees the purpose that press off new crack, repeatedly launching chemical packer can promote a plurality of secondary crack volume to open, and be finally reached more
The relative equilibrium of crack extends, and cuts compact reservoir to the greatest extent.It is exemplified below: assuming that the different perforating sites of horizontal well
Fracture pressure value be it is different, corresponding fracture pressure is respectively 20MPa, 25MPa, 30MPa, 35MPa.When shaft bottom is pressed
When power reaches 20MPa, the first crack is first pressed off；It is subsequently injected into chemical packer and realizes that the first crack sealing temporarily blocks up, well
It builds the pressure in cylinder, bottom pressure starts to increase, and when bottom pressure is increased to 25MPa, the second crack is pressed off；Continue injectionization
It learns packer and blocks Article 2 crack, build the pressure in pit shaft, bottom pressure continues to increase, when bottom pressure is increased to 30MPa, the
Three cracks are pressed off, and so on.The condition that interlayer turns to is that bottom pressure increment is greater than interlayer fracture pressure difference.The skill
The advantages of art: on the basis of not increasing segmentation tool, can in the construction process by deliver chemical packer number with
Quantity come realize it is each segmentation internal fissure quantity, spacing and scale control.
But the existing generally existing deficiency of chemical packer, firstly, dissolubility is poor, degradation rate is low, in fracturing fluid only
It can be partly dissolved, there are solid residues；Secondly, compression strength is low, stability resistant to high temperatures is poor；Directly influence pressing crack construction.
Patent CN201710118249.6 discloses a kind of low-density, high-strength degradable chemical packer and its preparation side
Method, including with the component of weight percent: polylactic acid 60-85%, starch 5-20%, polycaprolactone 5-10%, solubilizer 2-
5%, toughener 2-5%.It is blended using the same starch of polylactic acid, polycaprolactone, solubilizer, the toughener after polymerization, extrusion molding
Molding, the preparation method belong to Physical Processing preparation process.The bearing strength of the packer is greater than 52MPa, and blocking agent is in reservoir temperature
48 hours when degree loses mechanical strength, final degradation time 168 hours；30 DEG C to 90 DEG C reservoirs of preference temperature.But above-mentionedization
The bearing strength for learning packer is not high enough, and degradation time is longer, and just 90 DEG C of preference temperature highest, the application range of packer has
Limit.
Summary of the invention
The purpose of the present invention is poor for dissolubility existing for existing chemical packer, degradation rate is low, and compression strength is low, resists
The disadvantages of poor high temperature stability, provides a kind of complete solvable high-intensitive chemical packer of green.
The complete solvable high-intensitive chemical packer of green provided by the invention, by material acid, acrylic acid, N- vinyl pyrrole
Alkanone causes polymerization under initiator effect and is made.Each raw material component weight percent is as follows: lactic acid 15-20%, acrylic acid 10-
15%, n-vinyl pyrrolidone 5-10%, distilled water 53-69%, initiator 0.02-0.05%.The initiator is over cure
Sour ammonium and sodium hydrogensulfite.
The packer temporarily blocks up construction suitable for 150 DEG C or more of oil/gas well.
The preparation method of the above-mentioned complete solvable high-intensitive chemical packer of green, includes the following steps:
(1) distilled water is added into reaction vessel, is passed through nitrogen displacement discharge air；
(2) reaction vessel is added in lactic acid, acrylic acid, n-vinyl pyrrolidone, is stirring evenly and then adding into initiator, adds
Heat makes reacting liquid temperature rise to 120 DEG C, and constant temperature is stirred to react 30min, and alkaline matter is then added and adjusts pH value of reaction system 7-
8；
(3) continuing heating makes reaction solution system be warming up to 150 DEG C, and constant temperature is stirred to react 4h, then, purifies, dry, obtains
Head product.
Preferably, the alkaline matter in step (2) is magnesium hydroxide, sodium hydroxide or potassium hydroxide.
Preferably, the head product that step (3) obtains passes through screw extruder heating melting and squeezes out, and is cut with pelletizer
It is granulated, is shaped to partial size in the particle of 3-8mm, alternatively, being machined to the temporary plugging ball of 5-25mm with injection molding.
Compared with prior art, the invention has the following advantages:
(1) using natural lactic acid as one of raw material, lactic acid carries out more the present invention with n-vinyl pyrrolidone, acrylic acid
First copolyreaction obtains the copolymer of soluble high molecular weight, and the copolymer is then processed into particle or spherical, is obtained
Chemical packer no biotoxicity, it is environmentally protective, there is good biological degradability, degradation solution is small to formation damage；Experiment knot
Fruit shows that the chemical packer is completely dissolved in different temperatures fracturing fluid environment, noresidue solid, degradation rate 100%；Pressure break
When diverting agent adds 5-10% in liquid, compression strength reaches 80MPa or more, and recovery of core permeability can reach after diverting agent degradation
99, and degradation solution is nontoxic, clean and environmental protection.
(2) chemical packer compression strength is high, reaches as high as 80Mpa, and heat-resistant stable is good, be suitable for 150 DEG C with
On oil/gas well temporarily block up construction.
(3) the chemical packer scope of application is big, strong applicability, can dissolve in clear water, acid solution, lye, Ke Yiyong
It is temporarily blocked up in pressure break, it can also be used to which acidification is temporarily stifled.
Further advantage, target and feature of the invention will be partially reflected by the following instructions, and part will also be by this
The research and practice of invention and be understood by the person skilled in the art.
Detailed description of the invention
Fig. 1, XX45006 well pressing crack construction figure.
Yield mapping after Fig. 2, XX45006 well pressure.
Fig. 3, XX41081 well pressing crack construction figure.
Yield mapping after Fig. 4, XX41081 well pressure.
Specific embodiment
Present invention will be described in further detail below with reference to the accompanying drawings, to enable those skilled in the art referring to specification text
Word can be implemented accordingly.
Embodiment 1
A kind of preparation method of the complete solvable high-intensitive chemical packer of green, includes the following steps: that (1) is anti-at 500 milliliters
200 grams of distilled water of addition in flask are answered, nitrogen displaced air is led to；(2) by 40 grams of lactic acid, 15 acrylic acid, 20 grams of N- vinylpyridines
Pyrrolidone monomer is added in flask and opens stirring, and 0.08 gram of persulfuric acid ammonium and 0.04 sodium sulfite is then added as initiation
Agent, and reaction solution system is gradually heated to 120 DEG C, adjusting reaction solution system pH to addition sodium hydroxide after constant temperature 30min is
7-8；(3) system temperature is risen into 150 DEG C and isothermal reaction 4.0h, obtained product is subjected to purification is dried to obtain head product to be total to
Polymers；(4) copolymer is passed through into screw extruder heating melting and squeezed out, cut and be granulated with pelletizer, be shaped to partial size in 3-
The particle of 8mm, or the temporary plugging ball of 5-25mm is machined to injection molding.
It is configured to temporarily block up slippery water fracturing fluid using the graininess chemistry plugging device of preparation, be formulated as follows:
The packing of+8% particle chemistry of+0.2% clay stabilizer of 0.1% drag reducer+0.1% cleanup additive of+0.1% fungicide
Device, wherein the percentage of each component refers to the weight percent of the component and fracturing fluid.
Experiment is tested for the property at 90 DEG C, chemical packer the performance test results are shown in Table 1.It can be seen that the chemistry
Packer degradation time 60h, degradation rate 100% is degradable, and compression strength is higher than 80MPa.
Table 1, chemical packer performance test data
Embodiment 2
A kind of preparation method of the complete solvable high-intensitive chemical packer of green, includes the following steps: that (1) is anti-at 500 milliliters
200 grams of distilled water of addition in flask are answered, nitrogen displaced air is led to；(2) then by 60 grams of lactic acid, 10 grams of acrylic acid, 25 grams of N- second
Vinyl pyrrolidone monomer is added in flask and opens stirring, and 0.08 gram of ammonium persulfate is then added and 0.04 sodium hydrogensulfite is made
For initiator, and reaction solution system is gradually heated to 120 DEG C, potassium hydroxide tune is added into system after isothermal reaction 30min
Section pH value is 7-8；(3) reaction solution system temperature is risen to 150 DEG C and isothermal reaction 4h, obtained product is subjected to purification drying
Obtain head product copolymer；(4) copolymer of synthesis is passed through into screw extruder heating melting and squeezed out, made with pelletizer cutting
Grain, is shaped to partial size in the particle of 3-8mm, or the temporary plugging ball of 5-25mm is machined to injection molding.
It is configured to temporarily block up slippery water fracturing fluid using the graininess chemistry plugging device of preparation, be formulated as follows:
+ 5% chemical packer powder of+0.2% clay stabilizer of 0.1% drag reducer+0.1% cleanup additive of+0.1% fungicide
End；Wherein, the percentage of each component refers to the weight percent of the component and fracturing fluid.
Experiment is tested for the property at 150 DEG C, chemical packer the performance test results are shown in Table 2.It can be seen that the chemistry
Packer degradation time 48h, degradation rate 100% are degradable；Under 150 DEG C of hot conditions, compression strength 80MPa.
Table 2, chemical packer performance test data
| Project | Index |
| Degradation time, h | 48 |
| Degradation rate, % | 100 |
| Compression strength, MPa | 80 |
| Recovery of core permeability, % | 97.7 |
| Breaking glue solution surface tension after dissolution, mN/m | 25.9 |
| Breaking glue solution anti-dilative after dissolution, % | 89.0 |
Application Example 1
Using XX45006 well as application and construction object, chemical packer prepared by embodiment 1 is applied to XX45006 well
In.The perforated interval situation of the well is shown in Table 3.
Table 3, XX45006 well perforated hole segment table
Put into primary particle chemical packer material to the well, powder chemistry packer material three times, well head pressure on
It rises, show to form new crack and stitches interior complex fracture, specific pressing crack construction is shown in Fig. 1.
Not going out liquid before the well pressure break, initial stage day oil-producing 2.2t, current day oil-producing 3.3t after pressure tires out and increases oil 338.2t,
Yield is shown in Fig. 2 after XX45006 well pressure.
Application example 2
Using XX41081 well as application and construction object, chemical packer prepared by embodiment 2 is applied to XX41081 well
In.The perforated interval situation of the well is shown in Table 4.
Table 4, XX41081 well perforated hole segment table
Put into primary particle chemical packer material to the well, powder chemistry packer material twice, well head pressure on
It rises, show to form new crack and stitches interior complex fracture, specific pressing crack construction is shown in Fig. 3.
Pressure break day before yesterday oil-producing 1.9t, initial stage day oil-producing 9.9t, current day oil-producing 3.3t after pressure, tires out and increases oil 737.9t, measure
Effect is preferable, and yield is shown in Fig. 4 after XX41081 well pressure.
In conclusion the present invention provides a kind of complete solvable high-intensitive chemical packers of green, using natural lactic acid conduct
One of raw material, lactic acid carry out multi-component copolymer with n-vinyl pyrrolidone, acrylic acid and react to obtain soluble high molecular weight
Copolymer, obtained chemical packer no biotoxicity is environmentally protective, has good biological degradability, degradation solution is to stratum
It injures small.The chemical packer compression strength is high, reaches as high as 80Mpa, heat-resistant stable is good, suitable for 150 DEG C or more
Oil/gas well temporarily blocks up construction.
Although the embodiments of the present invention have been disclosed as above, but itself and be only limited to listed fortune in specification and embodiments
With.It can be applied to various suitable the field of the invention completely.It for those skilled in the art, can be easily real
Now other modification.Therefore without departing from the general concept defined in the claims and the equivalent scope, the present invention is not limited to
Specific details and legend shown and described herein.
Claims (7)
1. a kind of complete solvable high-intensitive chemical packer of green, which is characterized in that by material acid, acrylic acid, N- vinylpyridine
Pyrrolidone causes polymerization under initiator effect and is made.
2. the complete solvable high-intensitive chemical packer of green as described in claim 1, which is characterized in that each raw material component weight hundred
Divide ratio as follows: lactic acid 15-20%, acrylic acid 10-15%, n-vinyl pyrrolidone 5-10%, distilled water 53-69%, causing
Agent 0.02-0.05%.
3. the complete solvable high-intensitive chemical packer of green as claimed in claim 2, which is characterized in that the initiator is over cure
Sour ammonium and sodium hydrogensulfite.
4. the complete solvable high-intensitive chemical packer of green as claimed in claim 2, which is characterized in that the packer is suitable for
150 DEG C or more of oil/gas well temporarily blocks up construction.
5. a kind of preparation method of the complete solvable high-intensitive chemical packer of green as described in claim 1-4 any one,
It is characterized in that, includes the following steps:
(1) distilled water is added into reaction vessel, is passed through nitrogen displacement discharge air；
(2) reaction vessel is added in lactic acid, acrylic acid, n-vinyl pyrrolidone, is stirring evenly and then adding into initiator, heating makes
Reacting liquid temperature rises to 120 DEG C, and constant temperature is stirred to react 30min, then adjusts pH value of reaction system 7-8；
(3) continuing heating makes reaction solution system be warming up to 150 DEG C, and constant temperature is stirred to react 4h, then, purifies, dry, obtains primiparity
Object.
6. the preparation method of the complete solvable high-intensitive chemical packer of green as described in right goes 5, which is characterized in that step (2)
It is middle that reaction system pH is adjusted using magnesium hydroxide, sodium hydroxide or potassium hydroxide.
7. the preparation method of the complete solvable high-intensitive chemical packer of green as described in right goes 6, which is characterized in that step (3)
Obtained head product passes through screw extruder heating melting and squeezes out, and is cut and is granulated with pelletizer, is shaped to partial size 3-8mm's
Particle, alternatively, being machined to the temporary plugging ball of 5-25mm with injection molding.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811466563.4A CN109503762A (en) | 2018-12-03 | 2018-12-03 | A kind of complete solvable high-intensitive chemical packer of green and preparation method thereof |
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| CN201811466563.4A CN109503762A (en) | 2018-12-03 | 2018-12-03 | A kind of complete solvable high-intensitive chemical packer of green and preparation method thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110242269A (en) * | 2019-06-21 | 2019-09-17 | 北京捷贝通石油技术股份有限公司 | A kind of overstocked cracking method of casing deformation well chemical packer segmented body |
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| CA2882213A1 (en) * | 2013-05-30 | 2014-12-04 | Southwest Petroleum University | Gel, plugging method using the same, and plugging and well-killing method using the same |
| CN108300439A (en) * | 2017-12-13 | 2018-07-20 | 北京捷贝通石油技术有限公司 | A kind of temporary stall of well fracturing is to water-soluble diverting agent and preparation method thereof |
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2018
- 2018-12-03 CN CN201811466563.4A patent/CN109503762A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2882213A1 (en) * | 2013-05-30 | 2014-12-04 | Southwest Petroleum University | Gel, plugging method using the same, and plugging and well-killing method using the same |
| CN108300439A (en) * | 2017-12-13 | 2018-07-20 | 北京捷贝通石油技术有限公司 | A kind of temporary stall of well fracturing is to water-soluble diverting agent and preparation method thereof |
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| CN110242269A (en) * | 2019-06-21 | 2019-09-17 | 北京捷贝通石油技术股份有限公司 | A kind of overstocked cracking method of casing deformation well chemical packer segmented body |
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Application publication date: 20190322 |