Composite multipolymer nano oil displacement agent

Abstract

The invention is applicable to the field of composite multi-polymer nano oil displacement agents, and particularly relates to a composite multi-polymer nano oil displacement agent, which is composed of silicon dioxide nanoparticles and a cationic acrylamide copolymer, the cationic acrylamide copolymer is obtained by a so-called Huffman degradation reaction of acrylamide and N, N-methacrylamide under the action of alkaline earth metal hydroxide and alkaline halate; the silicon dioxide nanoparticles are prepared by mixing a silicon powder mixed solution at 45 DEG C with a sodium hydroxide solution and then mixing dopamine hydrochloride with a trihydroxymethyl aminomethane solution with the mass fraction of 20%. According to the composite multipolymer nano oil displacement agent provided by the invention, a cationic acrylamide copolymer and silicon dioxide are used as components of the oil displacement agent, and a high-pressure-resistant benzene ring chain structure is introduced into a molecular chain of the acrylamide copolymer, so that the structural stability of the nano oil displacement agent under high pressure is improved.

Description

Technical Field

[0001] The invention belongs to the field of composite multi-polymer nano oil-displacing agents, and in particular relates to a composite multi-polymer nano oil-displacing agent. Background Art

[0002] The oil recovery process can be divided into primary oil recovery, secondary oil recovery and tertiary oil recovery. The first two oil recovery processes are physical oil recovery, while the tertiary oil recovery process uses chemical methods to improve the properties of oil, gas, water and rock to recover more oil. The most important chemical is the composite multi-polymer nano-oil displacement agent.

[0003] Composite multi-polymer nano-oil-displacing agent (or production-increasing agent) is a kind of agent that changes the properties of the oil-water interface, reduces the viscosity of the oil, enhances the fluidity of the oil, and thus increases the production of oil and gas wells. The application of composite multi-polymer nano-oil-displacing agent is mainly concentrated in the petroleum industry.

[0004] The existing invention patent 201210553889.7 is a high-efficiency composite multi-polymer nano oil-displacing agent, which improves the recovery rate by improving the flow resistance of heavy oil through the use of carboxyl and sulfonic acid groups of hydrophilic groups and carbon-hydrogen bonds in lipophilic group sulfonates. However, in actual use and production processes, the composite multi-polymer nano oil-displacing agent has low stability and is prone to change under high-pressure environments, and the recovery rate is not high in the actual recovery process.

[0005] In summary, a new composite multi-polymer nano-oil-displacing agent is urgently needed to solve the problems of the existing composite multi-polymer nano-oil-displacing agents being unstable and prone to change under high-pressure environments. Utility Model Content

[0006] The embodiment of the present invention provides a composite multi-polymer nano oil-displacing agent, which aims to solve the problem that the existing composite multi-polymer nano oil-displacing agent has low stability and is easily changed under high pressure environment.

[0007] The embodiment of the present invention is implemented as follows:

[0008] A composite multi-polymer nano oil-displacing agent, which is composed of silicon dioxide nanoparticles and cationic acrylamide copolymer;

[0009] Cationic acrylamide copolymers are obtained by the so-called Hofmann degradation reaction of acrylamide and N,N-methyl acrylamide under the action of alkaline earth metal hydroxides and alkaline halogenates;

[0010] The silicon dioxide nanoparticles are prepared by mixing a silicon powder mixture at 45° C. with a sodium hydroxide solution, and then mixing dopamine hydrochloride and a tris(hydroxymethyl)aminomethane solution with a mass fraction of 20%.

[0011] Furthermore, the cationic acrylamide copolymer needs to be treated as follows:

[0012] (1) neutralizing the pH value of the cationic acrylamide copolymer to 6 to obtain a polymer aqueous solution with a concentration D1 equal to 100000 mPa.s;

[0013] (2) Add clean water to the polymer aqueous solution until the pH of the polymer aqueous solution drops to between 2 and 5.

[0014] Furthermore, the specific preparation steps of silicon powder are:

[0015] (1) taking a sodium hydroxide solution with a mass fraction of 15%, placing it at a temperature of 300°C for cracking for 30 to 35 minutes, neutralizing it with a sulfuric acid solution with a mass fraction of 40%, and allowing it to stand for precipitation to obtain a peat cracking solution;

[0016] (2) neutralizing the peat pyrolysis solution with hydrochloric acid, washing the precipitate, and drying and screening the precipitate to obtain mixed silicon powder;

[0017] (3) mixing the mixed silicon powder and sodium hydroxide, heating to 95° C., high-speed centrifuging, filtering to remove the precipitate, and collecting to obtain a purified mixed solution;

[0018] (4) The mixed solution is purified by adjusting hydrochloric acid with a mass fraction of 15%, and filtered to separate to obtain modified silicon powder.

[0019] The beneficial effects achieved by the present invention are:

[0020] The invention provides a composite multi-polymer nano oil-displacing agent. Cationic acrylamide copolymer and silicon dioxide are used as components of the oil-displacing agent, and a high-pressure-resistant benzene ring chain structure is introduced into the molecular chain of the acrylamide copolymer to improve the structural stability of the nano oil-displacing agent under high pressure. At the same time, the cationic acrylamide copolymer and silicon dioxide are polymerized by polymerization reaction, and the original preparation equipment can be used without increasing the cost. The invention is easy to operate and popularize. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a flow chart of the cationic acrylamide copolymer provided by the present invention;

[0022] Figure 2 This is a stability experimental data diagram of the composite multi-polymer nano oil-displacing agent of the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] The invention provides a composite multi-polymer nano oil-displacing agent. Cationic acrylamide copolymer and silicon dioxide are used as components of the oil-displacing agent, and a high-pressure-resistant benzene ring chain structure is introduced into the molecular chain of the acrylamide copolymer to improve the structural stability of the nano oil-displacing agent under high pressure. At the same time, the cationic acrylamide copolymer and silicon dioxide are polymerized by polymerization reaction, and the original preparation equipment can be used without increasing the cost. The invention is easy to operate and popularize.

[0025] Embodiment 1

[0026] In the embodiment of the present invention, this embodiment provides a composite multi-polymer nano oil displacement agent composed of silica nanoparticles and cationic acrylamide copolymer;

[0027] Cationic acrylamide copolymers are obtained by the so-called Hofmann degradation reaction of acrylamide and N,N-methyl acrylamide under the action of alkaline earth metal hydroxides and alkaline halogenates;

[0028] The silicon dioxide nanoparticles are prepared by mixing a silicon powder mixture at 45° C. with a sodium hydroxide solution, and then mixing dopamine hydrochloride and a tris(hydroxymethyl)aminomethane solution with a mass fraction of 20%.

[0029] Reference Figure 1 , cationic acrylamide copolymer also needs to be treated, the specific steps are:

[0030] S101: neutralizing the pH value of the cationic acrylamide copolymer to 6, and obtaining a polymer aqueous solution with a concentration D1 equal to 100000 mPa.s;

[0031] S102: adding clean water to the polymer aqueous solution until the pH of the polymer aqueous solution drops to between 2 and 5.

[0032] (1) taking a sodium hydroxide solution with a mass fraction of 15%, placing it at a temperature of 300°C for cracking for 30 to 35 minutes, neutralizing it with a sulfuric acid solution with a mass fraction of 40%, and allowing it to stand for precipitation to obtain a peat cracking solution;

[0033] (2) neutralizing the peat pyrolysis solution with hydrochloric acid, washing the precipitate, and drying and screening the precipitate to obtain mixed silicon powder;

[0034] (3) mixing the mixed silicon powder and sodium hydroxide, heating to 95° C., high-speed centrifuging, filtering to remove the precipitate, and collecting to obtain a purified mixed solution;

[0035] (4) The mixed solution is purified by adjusting hydrochloric acid with a mass fraction of 15%, and filtered to separate to obtain modified silicon powder.

[0036] By using cationic acrylamide copolymer and silica as components of the oil-displacing agent, a high-pressure-resistant benzene ring chain structure is introduced into the molecular chain of the acrylamide copolymer to improve the structural stability of the nano-oil-displacing agent under high pressure. At the same time, the cationic acrylamide copolymer and silica are polymerized by polymerization reaction, and the original preparation equipment can be used without increasing costs. It is easy to operate and easy to promote.

[0037] In the description of this specification, the description with reference to the terms "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0038] In addition, the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A composite multi-polymer nano oil-displacing agent, characterized in that: The composite multi-polymer nano oil displacement agent is composed of silica nanoparticles and cationic acrylamide copolymer; Cationic acrylamide copolymers are obtained by the so-called Hofmann degradation reaction of acrylamide and N,N-methyl acrylamide under the action of alkaline earth metal hydroxides and alkaline halogenates; The silicon dioxide nanoparticles are prepared by mixing a silicon powder mixture at 45° C. with a sodium hydroxide solution, and then mixing dopamine hydrochloride and a tris(hydroxymethyl)aminomethane solution with a mass fraction of 20%.

2. The composite multi-polymer nano oil-displacing agent according to claim 1, characterized in that: Cationic acrylamide copolymers also need to be treated as follows: (1) neutralizing the pH value of the cationic acrylamide copolymer to 6 to obtain a polymer aqueous solution with a concentration D1 equal to 100000 mPa.s; (2) Add clean water to the polymer aqueous solution until the pH of the polymer aqueous solution drops to between 2 and 5.

3. The composite multi-polymer nano oil-displacing agent according to claim 1, characterized in that: The specific preparation steps of silicon powder are: (1) taking a sodium hydroxide solution with a mass fraction of 15%, placing it at a temperature of 300°C for cracking for 30 to 35 minutes, neutralizing it with a sulfuric acid solution with a mass fraction of 40%, and allowing it to stand for precipitation to obtain a peat cracking solution; (2) neutralizing the peat pyrolysis solution with hydrochloric acid, washing the precipitate, and drying and screening the precipitate to obtain mixed silicon powder; (3) mixing the mixed silicon powder and sodium hydroxide, heating to 95° C., high-speed centrifuging, filtering to remove the precipitate, and collecting to obtain a purified mixed solution; (4) The mixed solution is purified by adjusting hydrochloric acid with a mass fraction of 15%, and filtered to separate to obtain modified silicon powder.

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