CN114621739B - Temperature-resistant salt-resistant super-hydrophobic particle plugging agent and preparation method thereof - Google Patents
Temperature-resistant salt-resistant super-hydrophobic particle plugging agent and preparation method thereof Download PDFInfo
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- CN114621739B CN114621739B CN202011447413.6A CN202011447413A CN114621739B CN 114621739 B CN114621739 B CN 114621739B CN 202011447413 A CN202011447413 A CN 202011447413A CN 114621739 B CN114621739 B CN 114621739B
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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
- C09K8/42—Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells
- C09K8/46—Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells containing inorganic binders, e.g. Portland cement
- C09K8/467—Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells containing inorganic binders, e.g. Portland cement containing additives for specific purposes
Abstract
The invention provides a temperature-resistant salt-resistant super-hydrophobic particle plugging agent and a preparation method thereof, and relates to the technical field of oilfield plugging agents, wherein the method comprises the following steps: (1) Adding ethyl orthosilicate into an alcohol solution, adding an acid solution, adjusting pH, stirring at constant temperature and refluxing; (2) Adding a mixed solution of an alkali solution and alcohol into the solution obtained in the step (1), heating and stirring for reaction; (3) Adding normal hexane into the solution obtained in the step (2), stirring, standing and centrifuging to obtain a solid substance; (4) And (3) adding the solid substance obtained in the step (3) into the hydrolyzed silane coupling agent, heating and stirring for reaction, and thus obtaining the particle plugging agent. The particle plugging agent comprises nano silicon dioxide particles and hydrophobic materials grafted on the nano silicon dioxide particles, and can realize good plugging effect.
Description
Technical Field
The invention relates to the technical field of oilfield plugging agents, in particular to a temperature-resistant salt-resistant super-hydrophobic particle plugging agent and a preparation method thereof.
Background
Because of poor stratum homogeneity, the clastic rock oil reservoir of the tower river has low success rate of water shutoff of the horizontal well and poor oil increasing effect, and the oil reservoir has extremely strong heterogeneity, the water outlet mechanism of the horizontal well is complex, and the general oil extraction rate is very low. The horizontal well is the main development oil well type of the existing clastic rock oil reservoir of the tower river, but the high water content of the oil well has seriously affected the development effect of the clastic rock horizontal well, and is the main contradiction of the high-efficiency development of the clastic rock horizontal well of the tower river. The water shutoff and profile control process is a main means for controlling water in the high-water-content horizontal well of the clastic rock oil reservoir of the tower river, and the water shutoff effect of the clastic rock horizontal well is always considerable from oil field development to the end of 2013. However, as the exploitation time increases, the potential of the oil well becomes smaller, the effect of the existing water shutoff technology becomes worse, the oil increment of a water shutoff single well gradually decreases, and the water shutoff effective rate is in a decreasing trend along with the water shutoff round. The prior horizontal well simple water shutoff profile control can not meet the profile control requirement of the horizontal well of the clastic rock oil reservoir in the tower river oil field.
Patent CN110387222A reports a porous gel blocking agent, a preparation method and application thereof, and relates to the technical field of gel blocking. The porous gel blocking agent is prepared by the polymerization reaction of raw materials comprising a monomer, a cross-linking agent, an initiator, an inorganic reinforcing material, a gas generating agent and water, and the gel blocking agent has a porous structure. The raw materials of the preparation method of the porous gel plugging agent adopt the raw materials, have the advantages of rapid gel formation and high colloid strength under medium and low temperature oil reservoirs (75-110 ℃), have good permeability, are a temporary plugging system easy to break gel and degrade, and are suitable for being applied to well completion, well repair, leakage prevention and plugging and temporary plugging fracturing acidification of oil and gas wells. The literature (application progress of nano materials in water shutoff and profile control of oil fields, oilfield chemistry [ J ], peng Baoliang and the like, 2016,33 (3): 552-556) reports that the nano materials improve the performance of water shutoff and profile control agents, play an increasingly important role in water shutoff and profile control of oil fields, introduce the structure and performance characteristics of the nano materials, outline the research and application progress of the nano materials in water shutoff and profile control of oil fields, discuss the performance of the nano materials in the aspects of regulating gel forming time, improving the stability and mechanical property of the water shutoff and profile control agents, improving the stability of emulsion and foam, and expand the application prospect of the nano composite materials in water shutoff and profile control of high-temperature deep well oil reservoirs, ultra-high permeability large pore oil reservoirs and low permeability oil reservoirs.
The heterogeneity of the clastic rock oil reservoir horizontal well causes low water to be introduced into or flew into, the high water content of the oil well is serious, the water shutoff of the early-stage superfine calcium carbonate has 3 problems, firstly, the controllability of the particle size is poor and bigger, and the depth of an entering stratum is shallow (less than 50 cm); secondly, the blocking strength is low (less than 60 percent); thirdly, the oil-water selectivity is not possessed. The prior horizontal well simple water shutoff profile control can not meet the profile control requirement of the horizontal well of the clastic rock oil reservoir in the tower river oil field. In order to solve the problems at present, a super-hydrophobic particle plugging agent with temperature resistance and salt resistance needs to be searched, so that a good plugging effect is realized.
Disclosure of Invention
Aiming at the problems existing in the prior art, the invention provides a porous nano silicon dioxide particle as a super-hydrophobic particle plugging agent with temperature resistance and salt resistance, which combines the unique quantum size effect and surface effect of nano particles and the auxiliary effects of reducing capillary pressure, wettability reversal, phase permeation change hysteresis effect and the like generated by a system to separate crude oil, paraffin, water and gas from the surface of rock, thereby realizing good plugging effect.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the invention provides a preparation method of a particle plugging agent, which comprises the following steps:
(1) Adding ethyl orthosilicate into an alcohol solution, adding an acid solution, adjusting pH, stirring at constant temperature and refluxing;
(2) Adding an alcohol solution into the solution obtained in the step (1), adding an alkali solution to adjust the pH, heating and stirring to react;
(3) Adding normal hexane into the solution obtained in the step (2), stirring, standing and centrifuging to obtain a solid substance;
(4) And (3) adding the solid substance obtained in the step (3) into the hydrolyzed silane coupling agent, heating and stirring for reaction, and thus obtaining the catalyst.
Further, in the step (1), the ph=2.5-3, the constant temperature is not higher than 20 ℃, and the stirring reflux time is 24-72h. Preferably, the constant temperature is 5-10 ℃, and the stirring reflux time is not less than 2d.
Further, the heating temperature in the step (2) is 40-50 ℃, the pH=8-10, and the stirring reaction time is 12-48h.
Further, in the step (3), the stirring time is 5-7h, the stirring speed is 10-20r/min, and the standing time is at least 12h.
Further, the heating temperature in the step (4) is 190-210 ℃, and the stirring reaction time is 3-10h.
Further, the amount of the silane coupling agent used in the step (4) is based on the immersed solid substance, and preferably the mass ratio of the solid substance to the silane coupling agent after the completion of the hydrolysis is 1:5-10.
Further, the alcohol in the step (1) and the step (2) is methanol or ethanol; the acid in step (1) comprises hydrofluoric acid, acetic acid or formic acid; the alkali in the step (2) comprises ammonia water, sodium hydroxide or potassium hydroxide.
Further, the mass fraction of the acid solution is 5-10%, so that the acid solution has a certain buffering effect on the system, and the problem that the particle size of the nano silicon dioxide particles is increased due to the fact that the pH value of the system is rapidly increased in the reaction process is avoided.
Further, the mass fraction of the ammonia water is 15-30%, and the concentration of the sodium hydroxide or the potassium hydroxide is 0.1mol/L.
Further, the mass ratio of the alcohol solution added in the step (1) to the alcohol solution added in the step (2) is 1:1.5-2.
Further, the molar ratio of the tetraethoxysilane, the alcohol solution and the acid solution in the step (1) is as follows: 1:1.2:0.05.
Further, the molar ratio of the n-hexane to the ethanol solution in the step (3) is 1:2.
Further, the silane coupling agent in the step (4) is one or more of methyltrimethoxysilane, gamma- (2, 3-glycidoxypropyl) trimethoxysilane, glycidoxypropyl trimethylsilane, vinyltrimethoxysilane, oxypropyl trimethylsilane methacrylate and aminopropyl trimethoxysilane. Preferably, the silane coupling agent is methyltrimethoxysilane and gamma- (2, 3-glycidoxy) propyltrimethoxysilane, and the mass ratio of the silane coupling agent to the gamma- (2, 3-glycidoxy) propyltrimethoxysilane is 1:1.
Further, the step (2) further comprises adding nano magnetic particles or a suspension of ferrous hydroxide; adding the nano magnetic particles or the suspension of ferrous hydroxide after the pH is adjusted; the particle size of the nano magnetic particles is not more than 30nm; and the molar ratio of the nano magnetic particles to the tetraethoxysilane is 0.01-0.05:1; the suspension of ferrous hydroxide is prepared by dissolving ferrous sulfate in ammonia water, and stirring for reaction; the molar ratio of the sulfated ferrous to the tetraethoxysilane is 0.03:1.
Further, step (4) further comprises adding formamide, acetamide, dimethylformamide or glycerin prior to heating and stirring.
The invention also provides the particle plugging agent prepared by the preparation method. The particle plugging agent comprises nano silicon dioxide particles and hydrophobic materials grafted on the nano silicon dioxide particles.
The invention has the technical effects that:
the invention discloses a temperature-resistant salt-resistant super-hydrophobic particle plugging agent and a preparation method thereof, wherein tetraethoxysilane is used as a raw material, nano silicon dioxide nano particles are obtained through gel, aging and solvent replacement, silane coupling agents with hydrophobic performance are grafted on the surfaces of the nano silicon dioxide particles, nano particles with porous structures are formed through the coupling performance of the silane coupling agents, the prepared particle plugging agent holes are uniformly distributed, the super-hydrophobic performance is achieved, and the nano particles can separate crude oil, paraffin, water and gas from the surfaces of rocks by combining the unique quantum size effect, the surface effect, the auxiliary effects of reducing capillary pressure, wettability reversal, phase permeability change hysteresis effect and the like of the nano particles, and achieve good plugging effect.
Detailed Description
It should be noted that the raw materials used in the present invention are all common commercial products, and therefore the sources thereof are not particularly limited.
Example 1
The invention discloses a temperature-resistant salt-resistant super-hydrophobic particle plugging agent which is prepared by the following method:
(1) Measuring ethanol, and adding water to prepare an ethanol solution with the mass fraction of 20% for later use; diluting hydrofluoric acid with water to be 0.05mol/L of dilute acid solution for standby; weighing ethyl orthosilicate according to the mol ratio of the ethyl orthosilicate to the ethanol of 1:1.2, adding the ethyl orthosilicate into an ethanol solution, then dropwise adding an acetic acid solution with the mass fraction of 10%, and regulating the pH value to be 2.5; stirring and refluxing for 2d at 10 ℃;
(2) Adding 20% ethanol solution by mass fraction into the system, slowly dropwise adding ammonia water under stirring to adjust the pH value of the system to 8-10, heating and stirring to 50 ℃, and continuing stirring and reacting for 16h under constant temperature;
(3) Adding n-hexane according to the molar ratio of n-hexane to ethanol (the total amount of ethanol used in the step (1) and the step (2)) of 1:2, stirring at a low speed for 5h under the condition of 10-20r/min, standing for 24h, and centrifuging to obtain a solid;
(4) And adding the obtained solid into the silane coupling agent after hydrolysis, and stirring and reacting for 8 hours at the temperature of 200 ℃ based on the immersed solid substance to obtain the product.
Example 2
The invention discloses a temperature-resistant salt-resistant super-hydrophobic particle plugging agent which is prepared by the following method:
(2) Adding 20% ethanol solution by mass fraction into the system, slowly dropwise adding ammonia water under stirring to adjust the pH value of the system to 8-10, adding ethanol dispersion liquid of nano silver particles after the ammonia water is dropwise added, heating and stirring to 50 ℃, and continuing stirring and reacting for 16h under constant temperature conditions; the remaining preparation steps were the same as in example 1, with the addition of nano silver particles in a molar ratio of 0.01:1 to ethyl orthosilicate.
Example 3
The invention discloses a temperature-resistant salt-resistant super-hydrophobic particle plugging agent which is prepared by the following method:
(2) Adding 20% ethanol solution by mass fraction into the system, slowly dropwise adding ammonia water under stirring to adjust the pH value of the system to 8-10, adding suspension of ferrous hydroxide after the ammonia water is dropwise added, heating and stirring to 50 ℃, and continuing stirring and reacting for 16h under constant temperature. The remaining preparation steps were the same as in example 1.
The suspension of ferrous hydroxide is prepared by dissolving ferrous sulfate in ammonia water, stirring and reacting to obtain the product; the molar ratio of ferrous hydroxide to ethyl orthosilicate is 0.03:1.
Example 4
The difference from example 1 was only that dimethylformamide was added before heating and stirring, and the amount of dimethylformamide added was 5% by mass of the solid matter.
Comparative example 1
The only difference from example 1 is that the acid addition step of step (1) is omitted.
Comparative example 2
The only difference from example 1 is that the alkalifying step of step (2) is omitted.
Comparative example 3
The only difference from example 1 is that in step (1) the acid is added but the reaction temperature is higher than 40 ℃.
The properties and parameters of the particulate blocking agents of examples 1-4 and comparative examples are shown in Table 1.
Wherein, the detection of the average particle diameter, specific surface area and water contact angle of the particle blocking agent is obtained by adopting a conventional method.
The water blocking performance at 120 ℃ is detected by adopting the following method: the plugging agent adopts stratum water and an emulsifying system (3.5% oleic acid imidazoline) to prepare a plugging system with the mass fraction of 5%, and then water-sealing plugging performance evaluation is carried out through a simulation experiment, wherein the injection amount is 0.1PV, the constant-temperature aging temperature is 120 ℃, and the constant-temperature aging time is 12h.
The 200000 mineralization degree water plugging performance adopts the following method: the plugging agent adopts stratum water and an emulsifying system (3.5% oleic acid imidazoline) to prepare a plugging system with the mass fraction of 5%, and then water blocking performance evaluation is carried out through a simulation experiment, wherein the injection amount is 0.1PV, and the mineralization degree of water used for water flooding is 200000mg/L.
TABLE 1
As is clear from Table 1, the particle blocking agent obtained in the present invention has a smaller average particle diameter in the range of 6.9-8.2nm and a larger specific surface area of 466-517m 2 The water blocking performance of 120 ℃ per gram is up to 80.9-85.2%, the mineralization degree of 200000 is up to 82.9-85.9%, and the water contact angle is up to 126.9-127.7 degrees, so that the particle blocking agent has good blocking effect. When no acid or alkali is added or the reaction temperature is changed in the preparation process, the plugging effect of the particle plugging agent is obviously reduced.
Finally, it should be noted that the above description is only for illustrating the technical solution of the present invention, and not for limiting the scope of the present invention, and that the simple modification and equivalent substitution of the technical solution of the present invention can be made by those skilled in the art without departing from the spirit and scope of the technical solution of the present invention.
Claims (5)
1. A preparation method of a particle plugging agent is characterized by comprising the following steps: the method comprises the following steps:
(1) Adding ethyl orthosilicate into an alcohol solution, adding an acid solution, adjusting pH, stirring at constant temperature and refluxing;
(2) Adding an alcohol solution into the solution obtained in the step (1), adding an alkali solution to adjust the pH, heating and stirring to react;
(3) Adding normal hexane into the solution obtained in the step (2), stirring, standing and centrifuging to obtain a solid substance;
(4) Adding the solid substance obtained in the step (3) into a silane coupling agent after hydrolysis, heating and stirring for reaction, thus obtaining the catalyst;
the acid in step (1) comprises hydrofluoric acid, acetic acid or formic acid; the alkali in the step (2) comprises ammonia water, sodium hydroxide or potassium hydroxide;
the silane coupling agent in the step (4) is one or more of methyltrimethoxysilane, gamma- (2, 3-glycidoxypropyl) propyltrimethoxysilane, glycidoxypropyl trimethylsilane, vinyltrimethoxysilane, oxypropyl trimethylsilane methacrylate and aminopropyl trimethoxysilane;
in the step (1), the pH=2.5-3, the constant temperature is not higher than 20 ℃, and the stirring reflux time is 24-72h; the heating temperature in the step (2) is 40-50 ℃, the pH=8-10, and the stirring reaction time is 12-48h;
the stirring time in the step (3) is 5-7h, and the standing time is at least 12h;
the heating temperature in the step (4) is 190-210 ℃, and the stirring reaction time is 3-10h.
2. The method of manufacturing according to claim 1, characterized in that: the alcohol in the step (1) and the step (2) is methanol or ethanol.
3. The method of manufacturing according to claim 1, characterized in that: step (2) also comprises adding nano magnetic particles or a suspension of ferrous hydroxide; adding the nano magnetic particles or the suspension of ferrous hydroxide after the pH is adjusted; the particle size of the nano magnetic particles is not more than 30nm; and the molar ratio of the nano magnetic particles to the tetraethoxysilane is 0.01-0.05:1; the suspension of ferrous hydroxide is prepared by dissolving ferrous sulfate in ammonia water, and stirring for reaction; the molar ratio of the sulfated ferrous to the tetraethoxysilane is 0.03:1.
4. The method of manufacturing according to claim 1, characterized in that: step (4) further comprises adding formamide acetamide, dimethylformamide or glycerol prior to heating and stirring.
5. A particulate plugging agent prepared by the preparation method of any one of claims 1 to 4.
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| CN105400503A (en) * | 2015-11-12 | 2016-03-16 | 中国石油大学(北京) | High-temperature-resistant and high-salt-resistant oil reservoir profile modifying water plugging agent and preparation method thereof |
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| CN109233770A (en) * | 2018-09-17 | 2019-01-18 | 天津大学 | A kind of high temperature resistant salt resistance elasticity profile control and water plugging particle and preparation method |
| CN111893766A (en) * | 2020-07-28 | 2020-11-06 | 西安科技大学 | Preparation method of multifunctional pH-responsive super-wetting material and application of multifunctional pH-responsive super-wetting material in oil-water separation |
| CN112029488A (en) * | 2020-08-13 | 2020-12-04 | 重庆地质矿产研究院 | Shale gas temporary plugging material and preparation method and application thereof |
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2020
- 2020-12-09 CN CN202011447413.6A patent/CN114621739B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105400503A (en) * | 2015-11-12 | 2016-03-16 | 中国石油大学(北京) | High-temperature-resistant and high-salt-resistant oil reservoir profile modifying water plugging agent and preparation method thereof |
| CN106115722A (en) * | 2016-06-23 | 2016-11-16 | 中国神华能源股份有限公司 | A kind of preparation method of aerosil |
| CN108165058A (en) * | 2017-12-30 | 2018-06-15 | 浙江工业大学 | A kind of preparation method of the micro-nano secondary structure super hydrophobic surface of silicon substrate |
| CN109233770A (en) * | 2018-09-17 | 2019-01-18 | 天津大学 | A kind of high temperature resistant salt resistance elasticity profile control and water plugging particle and preparation method |
| CN111893766A (en) * | 2020-07-28 | 2020-11-06 | 西安科技大学 | Preparation method of multifunctional pH-responsive super-wetting material and application of multifunctional pH-responsive super-wetting material in oil-water separation |
| CN112029488A (en) * | 2020-08-13 | 2020-12-04 | 重庆地质矿产研究院 | Shale gas temporary plugging material and preparation method and application thereof |
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