CN114426820A - Temporary plugging ball and manufacturing method and application thereof - Google Patents
Temporary plugging ball and manufacturing method and application thereof Download PDFInfo
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- CN114426820A CN114426820A CN202011020847.8A CN202011020847A CN114426820A CN 114426820 A CN114426820 A CN 114426820A CN 202011020847 A CN202011020847 A CN 202011020847A CN 114426820 A CN114426820 A CN 114426820A
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/50—Compositions for plastering borehole walls, i.e. compositions for temporary consolidation of borehole walls
- C09K8/516—Compositions for plastering borehole walls, i.e. compositions for temporary consolidation of borehole walls characterised by their form or by the form of their components, e.g. encapsulated material
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/50—Compositions for plastering borehole walls, i.e. compositions for temporary consolidation of borehole walls
- C09K8/504—Compositions based on water or polar solvents
- C09K8/506—Compositions based on water or polar solvents containing organic compounds
- C09K8/508—Compositions based on water or polar solvents containing organic compounds macromolecular compounds
- C09K8/5083—Compositions based on water or polar solvents containing organic compounds macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
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- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/50—Compositions for plastering borehole walls, i.e. compositions for temporary consolidation of borehole walls
- C09K8/504—Compositions based on water or polar solvents
- C09K8/506—Compositions based on water or polar solvents containing organic compounds
- C09K8/508—Compositions based on water or polar solvents containing organic compounds macromolecular compounds
- C09K8/5086—Compositions based on water or polar solvents containing organic compounds macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
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- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/50—Compositions for plastering borehole walls, i.e. compositions for temporary consolidation of borehole walls
- C09K8/504—Compositions based on water or polar solvents
- C09K8/506—Compositions based on water or polar solvents containing organic compounds
- C09K8/508—Compositions based on water or polar solvents containing organic compounds macromolecular compounds
- C09K8/514—Compositions based on water or polar solvents containing organic compounds macromolecular compounds of natural origin, e.g. polysaccharides, cellulose
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- 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
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/12—Packers; Plugs
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- 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
- E21B43/25—Methods for stimulating production
- E21B43/26—Methods for stimulating production by forming crevices or fractures
- E21B43/261—Separate steps of (1) cementing, plugging or consolidating and (2) fracturing or attacking the formation
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- C09K2208/00—Aspects relating to compositions of drilling or well treatment fluids
- C09K2208/04—Hulls, shells or bark containing well drilling or treatment fluids
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Abstract
The invention discloses a temporary plugging ball, which comprises: a core comprised of a first material selected from one or more of water-soluble polyvinyl alcohol, wood chips, paper sand, bentonite, moldable soluble clay, and a binder; a middle layer completely wrapping the core, composed of a second material selected from one or more of modified polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), polyester Thermoplastic Polyurethane (TPU), high polymerization degree polyvinyl alcohol (PVA); a shell layer completely covering the intermediate layer, and made of a third material selected from one or more of polyester TPU, polyglycolic acid and modified starch.
Description
Technical Field
The invention belongs to the technical field of oil field exploration downhole operation, and particularly relates to a temporary plugging ball which is prepared from water-soluble materials and has a core-shell structure and is used for fracturing steering and a preparation technology thereof, wherein the temporary plugging ball is used for improving oil and gas recovery ratio.
Background
In the process of continuous development, oil and gas are hidden, and the sleeve perforation needs to be subjected to staged fracturing so as to gradually and fully collect formation oil and gas energy. In order to avoid repeated fracturing, a technique of staged, time-shared, directional fracturing has recently emerged in which a regulatable temporary plugging agent material is used. The temporary plugging agent is mainly applied to fracturing steering operation and is used when a well needs to be segmented or steered to fracture and open a seam. The action mechanism of the technology is that a part of temporary plugging agent is squeezed into a stratum before fracturing, and after a well is closed and pressure is built for a period of time, a complex fracture network is opened; or the temporary plugging agent is injected into the holes or the seams to force the holes or the seams to generate new cracks, so that the communication of a new high oil-gas-containing area is enhanced, and the transformation capability of the oil-gas well is improved. The fracturing diversion of the invention mainly aims at the oriented perforation induced fracturing technology, and mainly diverts the bottom perforation of the stratum from the shallow perforation to the preferential fracturing. When the deep fracturing is carried out in the well, the fracturing fluid flows preferentially to the direction with lower resistance, which causes the difficulty that the fracturing fluid flows to the perforation at the deeper position of the stratum, so that the perforation at the shallower position of the stratum needs to be temporarily blocked, and then the fracturing fluid is forced to fill the perforation at the bottom of the stratum under higher pressure.
The temporary plugging ball is used for temporarily plugging the perforation of the shallow fracturing of the stratum (namely the perforation at the position with lower flow resistance), and preferentially fracturing the perforation at the position with higher flow resistance and low permeability of the stratum. The conventional fracturing steering technology adopts a metal temporary plug which needs to be drilled and removed after the fracturing steering operation is finished, and then the next stage of fracturing is carried out. Later, low-molecular-weight compound fracturing temporary plugging agents are developed gradually and can be divided into temporary plugging of plugging balls (plastic balls, rubber balls and wax balls), temporary fiber plugging, temporary plugging of large-particle-size propping agents and the like, but the substances are often undegradable or cannot be ablated, and flowback is often required after fracturing. In order to solve the problem that the traditional temporary plugging element or temporary plugging agent cannot be automatically ablated, a temporary plugging agent technology which can meet the requirement of fracturing steering operation in the underground environment within required time, effectively plug fractured layer perforation blastholes and degrade or slowly ablate within set time due to physical or chemical action needs to be developed.
Disclosure of Invention
The invention aims to develop a three-layer core-shell temporary plugging ball prepared from a degradable or water-soluble polymer composite material and a preparation technology thereof, wherein the temporary plugging ball is required to have certain deformation capacity at 120-150 ℃, can plug a perforation hole of 10-15 mm under the underground pressure of more than 50MPa without ball body fragmentation, and can be quickly and completely ablated in a short time after fracturing operation. On one hand, the fracturing steering operation under the underground environment with higher temperature and higher pressure is realized, on the other hand, the difficult problems of later-stage blockage removal and flowback operation are thoroughly solved, the construction procedures are reduced, the fracturing operation efficiency is improved, the cost is reduced, and the oil gas recovery ratio is improved.
Specifically, in a first aspect of the present invention, there is provided a temporary plugging ball comprising:
a core comprised of a first material selected from one or more of water-soluble polyvinyl alcohol, wood chips, paper sand, bentonite, moldable soluble clay, and a binder; these materials are selected because they are spherical when mixed, bonded, molded or molded with water or a binder, have a certain hardness and strength when dried, and soften or disperse when exposed to water.
A middle layer completely wrapping the core, composed of a second material selected from one or more of modified polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), polyester Thermoplastic Polyurethane (TPU), high polymerization degree polyvinyl alcohol (PVA); the materials are soluble in water or can be degraded in water environment, the water solubility or degradation rate of the materials is slower than that of the first material, and the second material has higher compressive mechanical strength;
a shell layer completely covering the intermediate layer, and made of a third material selected from one or more of polyester TPU, polyglycolic acid and modified starch. The water-soluble or degradable rate of the third material of the shell layer is smaller than that of the first material and is higher or not lower than that of the second material, so that the shell layer can be rapidly dissolved in water or degraded under the condition of fracture, and the temporary plugging function of the material of the intermediate layer is not influenced.
In a preferred embodiment of the invention, the second material has a slower degradation rate or water solubility rate than the first material. After the temporary plugging operation is finished, the ball core structure without the temporary plugging fracturing function can be quickly dissolved in water or degraded, so that the temporary plugging operation efficiency is improved.
In a preferred embodiment of the present invention, the diameter of the temporary plugging ball is 15 to 25 mm.
In a preferred embodiment of the present invention, the core has a diameter of 5 to 10 mm.
In a preferred embodiment of the present invention, the thickness of the intermediate layer is 2 to 5 mm.
In a preferred embodiment of the present invention, the shell layer has a thickness of 2 to 5 mm.
In a preferred embodiment of the present invention, the elastic modulus of the shell layer is less than 50 MPa. The low modulus outer shell has better deformability.
In a further preferred embodiment of the invention, the density of the temporary plugging ballThe degree is less than or equal to 1.3g/cm3。
A second aspect of the present invention relates to a method for producing the temporary plugging ball, comprising:
(1) mixing and softening the first material, molding by a mold, and drying to prepare a ball core with the diameter of 5-10 mm;
(2) preparing a second material, placing the prepared ball core into a cavity of an injection mold, plasticizing the second material, injecting and filling the mold, maintaining the pressure, cooling and demolding, and coating an intermediate layer on the outer layer of the ball core;
(3) and (3) placing the ball core coated with the middle layer prepared in the step (2) into a cavity of an injection mold by adopting a pre-embedded injection molding process, plasticizing the third material, injecting and filling the mold, maintaining the pressure, cooling and demolding to finally prepare the temporary plugging ball with the diameter of 15-25 mm.
In a preferred embodiment of the invention, the temperature in the injection mould cavity is room temperature.
The third aspect of the invention also discloses an application of the temporary plugging ball in fracturing steering operation. The temporary plugging ball has good water solubility, and after the shell layer of the temporary plugging ball is ablated or broken, the ball core structure of the temporary plugging ball can be ablated rapidly in the underground environment, and plugging removal operation after fracturing steering operation is not needed.
ADVANTAGEOUS EFFECTS OF INVENTION
(1) The shell layer with low modulus has better deformation capability and resists pressure of at least 50 Mpa;
(2) the high-temperature-resistant steel can bear a high working temperature environment of 100-150 ℃;
(3) the temporary plugging ball core structure has good water solubility, and after the temporary plugging ball shell is ablated or broken, the temporary plugging ball core structure can be rapidly ablated in an underground environment, and plugging removal operation after fracturing steering operation is not needed.
Drawings
FIG. 1 is a schematic diagram of a core-shell type temporary plugging ball structure.
Detailed Description
The invention will be further explained with reference to the drawings.
In order to make the technical solutions and advantages of the present invention clearer, the following embodiments are used to clearly and completely describe the solutions of the present invention.
The invention is described in further detail below with reference to the accompanying drawings:
example 1: in the core-shell type temporary plugging ball in the embodiment, the shell layer 1 adopts polyester TPU with the hardness of Shore 70A, the main component of the shell layer 2 is PBAT, and the component of the ball core 3 is PVA with low polymerization degree (the polymerization degree is 500, the alcoholysis degree is 50-75%, and the molecular weight is 2.5-3.5 ten thousand); the diameter of the ball core 3 is 10mm, and the ball core 3 is prepared by injection molding; the middle layer 2 is made of PBAT material, the thickness is 3mm, the ball core 3 is pre-arranged in a mould, the temperature of the mould is room temperature, and the PBAT is plasticized and injected into the mould to prepare a temporary plugging ball blank with the diameter of 16 mm; the thickness of the shell layer 1 is 2mm, the temporary plugging ball blank is pre-placed into a die, the temperature of the die is room temperature, and the TPU is plasticized and then injected into the die to finally obtain the temporary plugging ball with the diameter of 20 mm.
Example 2: a core-shell type temporary plugging ball composed of degradable or water-soluble high polymer materials is characterized in that a shell layer 1 is polyester TPU with the hardness of 70A Shore, a middle layer 2 is mainly composed of PLA, and a ball core 3 is composed of a mixture of paper sand and dextrin; the diameter of the ball core 3 is 10mm, and the ball core 3 is prepared by injection molding; the middle layer 2 is made of PLA material, the thickness is 3mm, the ball core 3 is pre-arranged in a mould, the temperature of the mould is room temperature, and the plasticized PLA is injected into the mould to prepare a temporary plugging ball blank with the diameter of 16 mm; the thickness of the shell layer 1 is 2mm, the temporary plugging ball blank is pre-placed into a die, the temperature of the die is room temperature, and the TPU is plasticized and then injected into the die to finally obtain the temporary plugging ball with the diameter of 20 mm.
Example 3: a core-shell type temporary plugging ball composed of degradable or water-soluble high polymer materials is characterized in that a shell layer 1 is made of polyglycolic acid, a middle layer 2 is mainly composed of PBAT, and a ball core 3 is a mixture of PVA with low polymerization degree and fine wood chips; the diameter of the ball core 3 is 10mm, and the ball core 3 is prepared by injection molding; the middle layer 2 is made of PBAT material, the thickness is 2mm, the ball core 3 is pre-arranged in a mould, the temperature of the mould is room temperature, and the PBAT is plasticized and injected into the mould to prepare a temporary plugging ball blank with the diameter of 14 mm; and the thickness of the shell layer 1 is 2mm, the temporary plugging ball blank is pre-placed into a die, the temperature of the die is room temperature, polyglycolic acid is plasticized and then injected into the die, and finally the temporary plugging ball with the diameter of 18mm is prepared.
Example 4: a core-shell temporary plugging ball composed of degradable or water-soluble high polymer materials is characterized in that a shell layer 1 is made of modified starch, a middle layer 2 mainly comprises polyester TPU with the hardness of Shore 70A, and a ball core 3 mainly comprises a mixture of bentonite and plastic soluble clay; the diameter of the ball core 3 is 5mm, and the ball core 3 is prepared by injection molding; the middle layer 2 is made of TPU material, the thickness is 2mm, the ball core 3 is pre-arranged in a die, the temperature of the die is room temperature, and the TPU is plasticized and then injected into the die to prepare a temporary plugging ball blank with the diameter of 10 mm; and the thickness of the shell layer 1 is 5mm, the temporary plugging ball blank is pre-placed into a die, the temperature of the die is room temperature, polyglycolic acid is plasticized and then injected into the die, and finally the temporary plugging ball with the diameter of 15mm is prepared.
Example 5: a core-shell type temporary plugging ball composed of degradable or water-soluble high polymer materials is characterized in that a shell layer 1 adopts polyglycolic acid, a middle layer 2 mainly comprises PLA, and a ball core 3 mainly comprises a mixture of PVA with low polymerization degree and fine wood chips; the diameter of the ball core 3 is 8mm, and the ball core 3 is prepared by injection molding; the middle layer 2 is made of PLA material, the thickness is 3mm, the ball core 3 is pre-arranged in a mould, the temperature of the mould is room temperature, and the plasticized PLA is injected into the mould to prepare a temporary plugging ball blank with the diameter of 11 mm; and the thickness of the shell layer 1 is 5mm, the temporary plugging ball blank is pre-placed into a die, the temperature of the die is room temperature, polyglycolic acid is plasticized and then injected into the die, and finally the temporary plugging ball with the diameter of 16mm is prepared.
Example 6: a core-shell type temporary plugging ball composed of degradable or water-soluble high polymer materials is characterized in that a shell layer 1 is made of polyglycolic acid, a middle layer 2 is mainly composed of PBAT, and a ball core 3 is a mixture of PVA with low polymerization degree and fine wood chips; the diameter of the ball core 3 is 8mm, and the ball core 3 is prepared by injection molding; the middle layer 2 is made of PBAT material, the thickness is 4mm, the ball core 3 is pre-arranged in a mould, the temperature of the mould is room temperature, and the PBAT is plasticized and injected into the mould to prepare a temporary plugging ball blank with the diameter of 16 mm; the thickness of the shell layer 1 is 3mm, the temporary plugging ball blank is pre-placed into a mould, the temperature of the mould is room temperature, polyglycolic acid is plasticized and then injected into the mould, and finally the temporary plugging ball with the diameter of 20mm is prepared.
Example 7: in the core-shell type temporary plugging ball in the embodiment, the shell layer 1 adopts polyester TPU with the hardness of Shore 70A, the main component of the middle layer 2 is PBAT, and the component of the ball core 3 is PVA with low polymerization degree (the polymerization degree is 500, the alcoholysis degree is 50-75%, and the molecular weight is 2.5-3.5 ten thousand); the diameter of the ball core 3 is 10mm, and the ball core 3 is prepared by injection molding; the middle layer 2 is made of PBAT material, the thickness is 5mm, the PVA ball core 3 is pre-arranged in a mould, the temperature of the mould is room temperature, and the PBAT is plasticized and injected into the mould to prepare a temporary plugging ball blank with the diameter of 20 mm; and (3) pre-placing the temporary plugging ball blank into a die with the temperature of room temperature when the thickness of the shell layer 1 is 5mm, plasticizing the TPU, and injecting the plasticized TPU into the die to finally obtain the temporary plugging ball with the diameter of 25 mm.
Example 8: a core-shell type temporary plugging ball composed of degradable or water-soluble high polymer materials is characterized in that a shell layer 1 is polyester TPU with the hardness of 70A Shore, a middle layer 2 is mainly composed of PLA, and a ball core 3 is composed of a mixture of paper sand and dextrin; the diameter of the ball core 3 is 10mm, and the ball core 3 is prepared by injection molding; the middle layer 2 is made of PBAT material, the thickness is 5mm, the ball core 3 is pre-arranged in a mould, the temperature of the mould is room temperature, and the plasticized PLA is injected into the mould to prepare a temporary plugging ball blank with the diameter of 18 mm; and (3) pre-placing the temporary plugging ball blank into a die with the temperature of room temperature when the thickness of the shell layer 1 is 5mm, plasticizing the TPU, and injecting the plasticized TPU into the die to finally obtain the temporary plugging ball with the diameter of 23 mm.
Example 9 application example
The temporary plugging balls prepared in examples 1-8 and comparative example 1 (common temporary plugging balls purchased from the market, mainly formed by PGA materials and having no core-shell structure) were subjected to ground plugging pressure test, the temporary plugging balls were placed in a closed cavity with small holes, the bottom of the closed cavity was tapered, the taper angle was 3-8 degrees, the small holes were located at the center of the bottom, and the diameter was 5mm smaller than the temporary plugging balls, so that the temporary plugging balls were placed in the closed cavity and dropped onto the small holes under the action of gravity, the closed cavity was filled with liquid, the entire sealed cavity was placed in a 120 ℃ constant temperature heating box, when the entire closed cavity and the liquid therein reached 120 ℃, the closed cavity was pressurized, and the plugging effect of the temporary plugging balls on the small holes under different pressures was recorded.
TABLE 1
As can be seen from the data of the examples and the comparative examples, the temporary plugging ball of the present invention has very good plugging effect and automatically dissolves after 4 to 7 days. The temporary plugging ball in the prior art has low pressure bearing capacity and general solubility, and cannot meet the repeated fracturing requirements of shale gas and deep wells and ultra-deep wells.
While the invention has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. It is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Claims (10)
1. A temporary plugging ball, comprising:
a core comprised of a first material selected from one or more of water-soluble polyvinyl alcohol, wood chips, paper sand, bentonite, moldable soluble clay, and a binder;
the middle layer completely covers the ball core and is made of a second material, and the second material is selected from one or more of modified polybutylene adipate-terephthalate, polylactic acid, polyester thermoplastic polyurethane and high-polymerization-degree polyvinyl alcohol;
a shell layer completely covering the intermediate layer, and made of a third material selected from one or more of polyester TPU, polyglycolic acid and modified starch.
2. The temporary plugging ball according to claim 1, wherein said temporary plugging ball has a diameter of 15-25 mm.
3. The temporary plugging ball according to claim 1 or 2, wherein said ball core has a diameter of 5-10 mm.
4. The temporary plugging ball according to any one of claims 1-3, wherein said intermediate layer has a thickness of 2-5 mm.
5. The temporary plugging ball according to any one of claims 1 to 4, wherein said shell layer has a thickness of 2 to 5 mm.
6. The temporary plugging ball according to any one of claims 1-5, wherein said shell layer has an elastic modulus lower than 50 MPa.
7. The temporary plugging ball according to any one of claims 1-6, wherein said temporary plugging ball has a density of ≤ 1.3g/cm3。
8. A method of manufacturing the temporary plugging ball according to any one of claims 1 to 7, comprising,
(1) mixing and softening the first material, molding by a mold, and drying to prepare a ball core with the diameter of 5-10 mm;
(2) preparing a second material, placing the prepared ball core into a cavity of an injection mold, plasticizing the second material, injecting and filling the mold, maintaining the pressure, cooling and demolding, and coating an intermediate layer on the outer layer of the ball core;
(3) and (3) placing the ball core coated with the middle layer prepared in the step (2) into a cavity of an injection mold by adopting a pre-embedded injection molding process, plasticizing the third material, injecting and filling the mold, maintaining the pressure, cooling and demolding to finally prepare the temporary plugging ball.
9. The method of claim 8, wherein the temperature within the injection mold cavity is room temperature.
10. Use of the temporary plugging ball according to any one of claims 1-7 in a frac diversion operation.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117264612A (en) * | 2023-11-23 | 2023-12-22 | 西南石油大学 | Controllable self-degrading temporary plugging reservoir protective agent for fractured hydrocarbon reservoir and preparation method |
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| WO2015061553A1 (en) * | 2013-10-23 | 2015-04-30 | Schlumberger Canada Limited | Development and characterization of degradable cross-linking in polyvinyl alcohol |
| CN107573913A (en) * | 2017-09-26 | 2018-01-12 | 中国石油化工股份有限公司 | A kind of perforation holes are temporarily blocked up with solvable degraded temporary plugging ball and preparation method thereof |
| CN110616065A (en) * | 2018-06-20 | 2019-12-27 | 中国石油化工股份有限公司 | High-interface-binding-force fiber particles for well cementation and preparation method thereof |
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| WO2015061553A1 (en) * | 2013-10-23 | 2015-04-30 | Schlumberger Canada Limited | Development and characterization of degradable cross-linking in polyvinyl alcohol |
| CN107573913A (en) * | 2017-09-26 | 2018-01-12 | 中国石油化工股份有限公司 | A kind of perforation holes are temporarily blocked up with solvable degraded temporary plugging ball and preparation method thereof |
| CN110616065A (en) * | 2018-06-20 | 2019-12-27 | 中国石油化工股份有限公司 | High-interface-binding-force fiber particles for well cementation and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117264612A (en) * | 2023-11-23 | 2023-12-22 | 西南石油大学 | Controllable self-degrading temporary plugging reservoir protective agent for fractured hydrocarbon reservoir and preparation method |
| CN117264612B (en) * | 2023-11-23 | 2024-01-30 | 西南石油大学 | Controllable self-degrading temporary plugging reservoir protective agent for fractured hydrocarbon reservoir and preparation method |
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