Tertiary amine modified CCUS anti-corrosion admixture as well as preparation method and application thereof

Abstract

The invention relates to the technical field of corrosion resistance of CCUS well cementation cement sheaths, in particular to a tertiary amine modified CCUS corrosion-resistant admixture as well as a preparation method and application thereof. And uniformly mixing the epoxy resin emulsion with the tertiary amine modified curing agent for reaction to obtain the tertiary amine modified CCUS corrosion-resistant admixture. The tertiary amine modified CCUS corrosion-resistant cement admixture system is prepared from the tertiary amine modified CCUS corrosion-resistant admixture, a fluid loss agent, a coagulation accelerator and a defoaming agent. The CCUS corrosion resistance of a cement matrix is improved by adding a tertiary amine modified CCUS corrosion-resistant cement admixture system into oil well cement. The tertiary amine modified CCUS corrosion-resistant cement system provided by the invention has excellent corrosion resistance, a composite corrosion-resistant structure is constructed through cooperation of a polymer film structure and tertiary amine group carbon adsorption, and the corrosion resistance of a cement matrix is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of CCUS cement sheath corrosion resistance technology, and in particular to a tertiary amine modified CCUS corrosion resistant admixture, its preparation method, and its application. Background Technology

[0002] To address the escalating greenhouse effect and extreme climate change, carbon capture, utilization, and storage (CCUS) technology has garnered increasing attention. This technology primarily involves capturing carbon dioxide and implementing geological storage or resource utilization. Among these technologies, carbon dioxide enhanced recovery technology (CO2-EOR) combines high recovery with carbon sequestration, enabling the extraction of remaining oil from oilfields while simultaneously utilizing industrial carbon emissions through the injection of carbon dioxide into oil wells. It is considered one of the core technologies of CCUS. However, in CCUS projects, carbon dioxide is often compressed to a supercritical state. Supercritical carbon dioxide mixes with water to form a corrosive fluid, causing carbonization corrosion of the oil well cement sheath. This leads to the deterioration of the cement sheath's performance. In severe cases, it can even lead to well destruction and localized carbon dioxide leakage. Therefore, preventing the corrosion of supercritical carbon dioxide is crucial for the large-scale application of CO2-EOR technology.

[0003] Compared to other methods, adding epoxy resin to a cement matrix can form a protective film on the surface of cement particles, thereby preventing corrosion from supercritical carbon dioxide. This is a promising method to enhance the corrosion resistance of cement matrices in extremely hot and high-pressure underground environments. Peng et al. prepared a waterborne epoxy resin based on E-54 and AMPS, successfully achieving corrosion resistance of the cement matrix against CO2 and H2S. Ajir et al. coated a cement matrix with an epoxy resin coating to prevent erosion by corrosive fluids. Zhang et al. developed a water-oil gradient composite epoxy resin modified cement-based repair mortar (MCEP), which significantly improved the impermeability and corrosion resistance of the cement matrix. Min et al. added a corrosion inhibitor composed of epoxy resin emulsion and antibacterial materials to the cement slurry, reducing the permeability and corrosion of the cement slurry.

[0004] Although epoxy resins have been used for corrosion protection of cementitious matrices, some inherent drawbacks limit their widespread application. Since most epoxy resins are oil-based, they must be water-based modified or emulsified to achieve better compatibility with cementitious matrices. The stability of epoxy resin emulsions is difficult to guarantee, and water-based epoxy resins are too expensive due to their complex synthesis processes. Furthermore, epoxy resins need to be used in conjunction with curing agents, making it difficult to control the pumping of cement slurry in actual CCUS projects due to the curing reaction of epoxy resins and the complex underground environment. To form a protective film that physically isolates supercritical carbon dioxide on the surface of cement particles, the amount of epoxy resin added is often quite high (epoxy resin content ≥ 4%). This further increases project costs and the uncertainty of slurry pumping. Therefore, this invention provides a novel tertiary amine-modified CCUS anti-corrosion cement system that significantly improves the corrosion resistance of the cement matrix by synergistically constructing a composite anti-corrosion structure through polymer film structure and tertiary amine group carbon adsorption. Summary of the Invention

[0005] Based on the above, this invention provides a tertiary amine-modified CCUS anti-corrosion admixture, its preparation method, and its application. The tertiary amine-modified CCUS anti-corrosion admixture of this invention is easy to industrialize. The tertiary amine-modified CCUS anti-corrosion cement system prepared using this tertiary amine-modified CCUS anti-corrosion admixture can meet the requirements of CCUS cementing and improve the corrosion resistance of the cement matrix under CCUS conditions.

[0006] To achieve the above objectives, the present invention provides the following solution: One of the technical solutions of this invention is a method for preparing a tertiary amine modified CCUS anti-corrosion additive, which involves mixing an epoxy resin emulsion with a tertiary amine modified curing agent and reacting the mixture to obtain the tertiary amine modified CCUS anti-corrosion additive.

[0007] In a preferred embodiment of the present invention, the epoxy resin emulsion is a bisphenol A epoxy resin emulsion, a bisphenol F epoxy resin emulsion, or a bisphenol S epoxy resin emulsion; the tertiary amine modified curing agent is dimethylaminopropylamine, dimethylaminopropylmethacrylamide, or N,N-diethyl-1,3-propanediamine.

[0008] In a preferred embodiment of the present invention, the mass ratio of the epoxy resin emulsion to the tertiary amine modified curing agent is (40~50):(50~60).

[0009] In a preferred embodiment of the present invention, the reaction conditions are set as follows: the reaction is carried out at 40~60°C for 4~6 hours.

[0010] The second technical solution of the present invention is a tertiary amine modified CCUS anti-corrosion additive prepared by the above preparation method.

[0011] The third technical solution of the present invention is a tertiary amine modified CCUS anti-corrosion cement admixture system, wherein, by mass parts, the raw materials include 40-55 parts of the above-mentioned tertiary amine modified CCUS anti-corrosion admixture, 40-55 parts of water loss reducing agent, 4-4.5 parts of setting accelerator and 0.5-1 parts of defoamer.

[0012] In a preferred embodiment of the present invention, the water loss reducing agent is DRF-1S, G301 or SMAS-1; the coagulant is sodium sulfate, calcium sulfate or aluminum sulfate; and the defoamer is P80A, D70F or P805.

[0013] The fourth technical solution of the present invention is the application of the above-mentioned tertiary amine modified CCUS anti-corrosion admixture and the above-mentioned tertiary amine modified CCUS anti-corrosion cement admixture system in the CCUS anti-corrosion cement system.

[0014] The fifth technical solution of the present invention is a tertiary amine modified CCUS anti-corrosion cement system, comprising the above-mentioned tertiary amine modified CCUS anti-corrosion cement admixture system and oil well cement.

[0015] In a preferred embodiment of the present invention, the mass ratio of the tertiary amine modified CCUS anti-corrosion cement admixture system to the oil well cement is (2~6):(94~98).

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The tertiary amine modified CCUS anti-corrosion cement admixture system provided by this invention is inexpensive and suitable for large-scale use.

[0017] 2. The tertiary amine modified CCUS anti-corrosion cement system provided by the present invention meets the requirements of CCUS cementing and has good rheological properties and thermal stability.

[0018] 3. The tertiary amine modified CCUS anti-corrosion cement system provided by the present invention has excellent anti-corrosion performance. By synergistically constructing a composite anti-corrosion structure through polymer film structure and carbon adsorption of tertiary amine groups, the anti-corrosion ability of the cement matrix is ​​significantly improved. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1The images shown are scanning electron microscope (SEM) images and X-ray energy dispersive spectroscopy (EDS) images of the tertiary amine modified CCUS anti-corrosion admixture prepared in Example 1 in a cement matrix. Among them, (a) is a morphology image of the tertiary amine modified CCUS anti-corrosion admixture in a cement matrix, (b) is a magnified view of a portion of the tertiary amine modified CCUS anti-corrosion admixture in a cement matrix, (c) is a carbon element distribution map, (d) is a nitrogen element distribution map, (e) is a silicon element distribution map, and (f) is an oxygen element distribution map. Figure 2 The thermogravimetric curves of the tertiary amine-modified CCUS anti-corrosion additive prepared in Example 1 are compared with the first derivative curves of the thermogravimetric curves. Figure 3 Carbonation depth diagrams of the blank cement system prepared as a control example and the tertiary amine modified CCUS anti-corrosion cement system prepared in Example 1 under CCUS conditions for 0 / 14 / 28 days; Figure 4 Pore ​​size distribution diagrams of the blank cement system prepared as a control example and the tertiary amine modified CCUS anti-corrosion cement system prepared in Example 1 under CCUS conditions for 0 / 14 / 28 days of corrosion. Figure 5 Rheological test diagrams of the blank cement system prepared as a control example and the tertiary amine modified CCUS anti-corrosion cement systems prepared in Examples 1-3. Detailed Implementation

[0021] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0022] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0023] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0024] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0025] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0026] The first aspect of this invention provides a method for preparing a tertiary amine modified CCUS anti-corrosion additive, wherein an epoxy resin emulsion is mixed with a tertiary amine modified curing agent and reacted to obtain the tertiary amine modified CCUS anti-corrosion additive.

[0027] In a preferred embodiment of the present invention, the mixing method is: stirring at 400-600 rpm.

[0028] In a preferred embodiment of the present invention, the epoxy resin emulsion is a bisphenol A epoxy resin emulsion, a bisphenol F epoxy resin emulsion, or a bisphenol S epoxy resin emulsion; the tertiary amine modified curing agent is dimethylaminopropylamine, dimethylaminopropylmethacrylamide, or N,N-diethyl-1,3-propanediamine.

[0029] Other curing agents commonly used in this field do not have a tertiary amine structure or have too low a tertiary amine content, which cannot impart a sufficient concentration of tertiary amine groups to the anti-corrosion additive. Therefore, this invention limits the tertiary amine modified curing agent to dimethylaminopropylamine, dimethylaminopropylmethacrylamide, or N,N-diethyl-1,3-propanediamine.

[0030] In a preferred embodiment of the present invention, the mass ratio of the epoxy resin emulsion to the tertiary amine modified curing agent is (40~50):(50~60).

[0031] In this invention, if the amount of tertiary amine modified curing agent is too small, the effective molecular structure of the additive cannot be formed; if the amount of tertiary amine modified curing agent is too large, the curing agent will be wasted, increasing costs and impurities. Therefore, this invention limits the mass ratio of epoxy resin emulsion to tertiary amine modified curing agent to the above-mentioned range.

[0032] In a preferred embodiment of the present invention, the reaction conditions are set as follows: the reaction is carried out at 40~60°C for 4~6 hours.

[0033] In this invention, excessively high reaction temperatures lead to an uncontrollable, excessively rapid reaction, while excessively low temperatures prevent the curing agent from fully reacting with the epoxy resin emulsion. Excessively long reaction times result in wasted equipment and increased costs, while excessively short reaction times prevent the curing agent from fully reacting with the epoxy resin emulsion. Therefore, this invention limits the reaction conditions to the aforementioned temperature and time range.

[0034] A second aspect of the present invention provides a tertiary amine-modified CCUS anti-corrosion additive prepared by the above preparation method.

[0035] The third aspect of the present invention provides a tertiary amine modified CCUS anti-corrosion cement admixture system, wherein, by mass parts, the raw materials include 40-55 parts of the above-mentioned tertiary amine modified CCUS anti-corrosion admixture, 40-55 parts of a water loss reducing agent, 4-4.5 parts of a setting accelerator, and 0.5-1 parts of a defoamer.

[0036] In this invention, excessive addition of the water loss reducing agent leads to increased costs of the admixture system and decreased cement strength, while insufficient addition fails to achieve the desired water loss reduction effect. Excessive addition of the setting accelerator causes premature setting of the cement paste, while insufficient addition results in delayed setting and substandard strength. Excessive addition of the defoamer reduces the strength of the cement matrix, while insufficient addition prevents the cement matrix from effectively eliminating air bubbles. Therefore, this invention limits the addition amounts of the water loss reducing agent, setting accelerator, and defoamer in the tertiary amine-modified CCUS anti-corrosion cement admixture system to the aforementioned parameter ranges.

[0037] In a preferred embodiment of the present invention, the water loss reducing agent is DRF-1S, G301 or SMAS-1; the coagulant is sodium sulfate, calcium sulfate or aluminum sulfate; and the defoamer is P80A, D70F or P805.

[0038] In this invention, the reasons for selecting the above-mentioned types of water loss reducing agent, coagulant accelerator, and defoamer are as follows: The above-mentioned water loss reducing agent, coagulant accelerator, and defoamer are the optimal system selected based on the anti-corrosion admixture, which can meet the construction requirements. Other admixtures have poor compatibility with anti-corrosion admixtures.

[0039] In a preferred embodiment of the present invention, the preparation method of the tertiary amine modified CCUS anti-corrosion cement admixture system is as follows: the raw materials are mixed and stirred at 400~600 rpm until homogeneous.

[0040] The fourth aspect of the present invention provides the above-mentioned tertiary amine modified CCUS anti-corrosion admixture and the application of the above-mentioned tertiary amine modified CCUS anti-corrosion cement admixture system in CCUS anti-corrosion cement system.

[0041] The fifth aspect of the present invention provides a tertiary amine modified CCUS anti-corrosion cement system, including the above-mentioned tertiary amine modified CCUS anti-corrosion cement admixture system and oil well cement.

[0042] In a preferred embodiment of the present invention, the mass ratio of the tertiary amine modified CCUS anti-corrosion cement admixture system to the oil well cement is (2~6):(94~98).

[0043] In a preferred embodiment of the present invention, the tertiary amine modified CCUS anti-corrosion cement system further includes water, with a water-cement ratio of 0.44.

[0044] Unless otherwise specified, the technical solutions described in this invention are all conventional solutions in the field, and the reagents or raw materials used are all purchased from commercial channels or are publicly available unless otherwise specified.

[0045] The G-grade oil well cement used in this embodiment of the invention was produced by Sichuan Jiahua Enterprise Co., Ltd.; the DRF-1S used was from China Petroleum Engineering Technology Research Institute Co., Ltd.; P80A was from Jiangsu Ningbao Materials Technology Co., Ltd.; G301 was from Weihui Chemical Co., Ltd.; D70F was from Jiangsu Ningbao Materials Technology Co., Ltd.; SMAS-1 was from China Petroleum Engineering Technology Research Institute Co., Ltd.; and P805 was from Shandong Landu New Materials Co., Ltd. However, this invention is not limited, and the above-mentioned raw materials obtained through other commercial channels can also be used in this invention.

[0046] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0047] Example 1 A method for preparing a tertiary amine-modified CCUS anti-corrosion cement system, comprising the following steps: (1) Preparation of tertiary amine modified CCUS anti-corrosion additive: Bisphenol A type epoxy resin emulsion and dimethylaminopropylamine (DMAPA) were mixed at a mass ratio of 1:1, stirred evenly at 400 rpm, and reacted at 40℃ for 4 h to obtain tertiary amine modified CCUS anti-corrosion additive.

[0048] (2) Preparation of tertiary amine modified CCUS anti-corrosion cement system: tertiary amine modified CCUS anti-corrosion admixture, DRF-1S, sodium sulfate and P80A were mixed and stirred at 400 rpm to obtain tertiary amine modified CCUS anti-corrosion cement admixture system. A tertiary amine-modified CCUS anti-corrosion cement admixture system, water, and Grade G oil well cement were prepared at a water-cement ratio of 0.44. The mass ratio of the tertiary amine-modified CCUS anti-corrosion cement admixture system to Grade G oil well cement was 6:94. The system was prepared according to GB / T 19139-2012 and cured in a curing chamber at 90℃±2℃ for 28 days to obtain the tertiary amine-modified CCUS anti-corrosion cement system. The mass fraction of the tertiary amine-modified CCUS anti-corrosion admixture in the tertiary amine-modified CCUS anti-corrosion cement admixture system was 55.0%; the mass fraction of DRF-1S in the tertiary amine-modified CCUS anti-corrosion cement admixture system was 40.0%; the mass fraction of sodium sulfate in the tertiary amine-modified CCUS anti-corrosion cement admixture system was 4.0%; and the mass fraction of P80A in the tertiary amine-modified CCUS anti-corrosion cement admixture system was 1.0%.

[0049] Figure 1 Scanning electron microscope (SEM) image and X-ray energy dispersive spectroscopy (EDS) image of the tertiary amine-modified CCUS anti-corrosion admixture prepared in Example 1 in a cement matrix. Figure 1 As can be seen from (a) and (b), the tertiary amine modified CCUS anti-corrosion cement admixture exhibits a polymer network structure in the cement matrix and has good compatibility with the cement matrix. Among them, the C element (Figure c) mainly comes from the polymer network structure of the tertiary amine modified CCUS anti-corrosion admixture, the N element (Figure d) comes from the tertiary amine groups on the polymer network structure of the tertiary amine modified CCUS anti-corrosion admixture, and the Si element (Figure e) and Ca element (Figure f) come from the cement matrix.

[0050] Figure 2 The thermogravimetric analysis (TGA) curves of the tertiary amine-modified CCUS anticorrosion additive prepared in Example 1 are compared with the first derivative curves of the TGA curves. Figure 2 It is known that the thermal decomposition temperature of tertiary amine modified CCUS anti-corrosion additive is 250-450 degrees Celsius, and the weight loss rate is 66.4%.

[0051] Example 2 The only difference from Example 1 is that the mass ratio of the tertiary amine modified CCUS anti-corrosion cement admixture system to Grade G oil well cement is 4:96.

[0052] Example 3 The only difference from Example 1 is that the mass ratio of the tertiary amine modified CCUS anti-corrosion cement admixture system to Grade G oil well cement is 2:98.

[0053] Example 4 A method for preparing a tertiary amine-modified CCUS anti-corrosion cement system, comprising the following steps: (1) Preparation of tertiary amine modified CCUS anti-corrosion additive: Bisphenol F epoxy resin emulsion and dimethylaminopropylmethacrylamide (DMAPMA) were mixed at a mass ratio of 45:55, stirred evenly at 500 rpm, and reacted at 50°C for 5 h to obtain tertiary amine modified CCUS anti-corrosion additive.

[0054] (2) Preparation of tertiary amine modified CCUS anti-corrosion cement system: tertiary amine modified CCUS anti-corrosion admixture, G301, calcium sulfate and D70F are mixed and stirred at 500 rpm to obtain tertiary amine modified CCUS anti-corrosion cement admixture system. A tertiary amine-modified CCUS anti-corrosion cement admixture system, water, and Grade G oil well cement were prepared at a water-cement ratio of 0.44. The mass ratio of the tertiary amine-modified CCUS anti-corrosion cement admixture system to Grade G oil well cement was 6:94. The system was prepared according to GB / T 19139-2012 and cured in a curing chamber at 90℃±2℃ for 28 days to obtain the tertiary amine-modified CCUS anti-corrosion cement system. The mass fraction of the tertiary amine-modified CCUS anti-corrosion admixture system was 45.0%; the mass fraction of G301 was 50.0%; the mass fraction of calcium sulfate was 4.3%; and the mass fraction of D70F was 0.7%.

[0055] Example 5 A method for preparing a tertiary amine-modified CCUS anti-corrosion cement system, comprising the following steps: (1) Preparation of tertiary amine modified CCUS anti-corrosion additive: Bisphenol S epoxy resin emulsion and N,N-diethyl-1,3-propanediamine were mixed at a mass ratio of 4:6, stirred evenly at 600 rpm, and reacted at 60℃ for 6 h to obtain tertiary amine modified CCUS anti-corrosion additive.

[0056] (2) Preparation of tertiary amine modified CCUS anti-corrosion cement system: tertiary amine modified CCUS anti-corrosion admixture, SMAS-1, aluminum sulfate and P805 were mixed and stirred at 600 rpm to obtain tertiary amine modified CCUS anti-corrosion cement admixture system. A tertiary amine-modified CCUS anti-corrosion cement admixture system, water, and Grade G oil well cement were prepared at a water-cement ratio of 0.44. The mass ratio of the tertiary amine-modified CCUS anti-corrosion cement admixture system to Grade G oil well cement was 6:94. The system was prepared according to GB / T 19139-2012 and cured in a curing chamber at 90℃±2℃ for 28 days to obtain the tertiary amine-modified CCUS anti-corrosion cement system. The mass fraction of the tertiary amine-modified CCUS anti-corrosion admixture in the tertiary amine-modified CCUS anti-corrosion cement admixture system was 40.0%; the mass fraction of SMAS-1 was 55.0%; the mass fraction of aluminum sulfate was 4.5%; and the mass fraction of P805 was 0.5%.

[0057] Comparison Example Construction of blank cement system: Water and G-grade oil well cement were mixed at a water-cement ratio of 0.44, prepared according to GB / T19139-2012, and cured in a curing box at 90℃±2℃ for 28 days.

[0058] Figure 3 Carbonation depth diagrams of the cross-sections after 0 / 14 / 28 days of corrosion under CCUS conditions for the blank cement system prepared as a control example and the tertiary amine modified CCUS anti-corrosion cement system prepared in Example 1. Figure 3 As can be seen, after corrosion at 90 degrees Celsius under a 10MPa carbon dioxide environment, the area of ​​the corrosion zone (unstained area) in the control example and Example 1 gradually increased with the increase of corrosion time; under the same corrosion time, the corrosion area of ​​the control example was much larger than that of Example 1, and Example 1 showed a significant anti-corrosion effect.

[0059] Figure 4 Pore ​​size distribution diagrams of the blank cement system prepared as a control example and the tertiary amine modified CCUS anti-corrosion cement system prepared in Example 1 under CCUS conditions for 0 / 14 / 28 days. From... Figure 4 As can be seen, after corrosion at 90 degrees Celsius under a 10MPa carbon dioxide environment, the number of 5-50nm pores in the control example and Example 1 increases with the increase of corrosion time; under the same corrosion time, the number of 5-50nm pores in Example 1 is much lower than that in the control example. The tertiary amine modified CCUS anti-corrosion cement system can inhibit the deterioration of the microstructure of the cement matrix caused by CCUS corrosion.

[0060] Figure 5The figures show the rheological test results of the tertiary amine-modified CCUS anti-corrosion cement systems prepared in the control example, Example 1, Example 2, and Example 3. As can be seen from the figures, the tertiary amine-modified CCUS anti-corrosion cement system exhibits Newtonian fluid behavior, with a consistency lower than that of the cement paste in the control example, indicating improved rheological properties of the cement matrix.

[0061] The CCUS corrosion resistance performance of the cement matrix prepared in Examples 2-5 was tested. The test results were similar to those in Example 1. The results show that the tertiary amine modified CCUS corrosion-resistant cement system prepared in this invention has excellent corrosion resistance, good thermal stability, and good rheological properties, which can meet the requirements of CCUS cementing.

[0062] In summary, the tertiary amine modified CCUS anti-corrosion cement system of this invention has a simpler preparation process, is easier to industrialize, is cheaper, is suitable for large-scale use, has good rheological properties and thermal stability, and can synergistically construct a composite anti-corrosion structure through polymer film structure and carbon adsorption of tertiary amine groups, which significantly improves the corrosion resistance of cement matrix and effectively solves the shortcomings of traditional CCUS anti-corrosion cement system in practical application and high price.

[0063] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing a tertiary amine modified CCUS corrosion inhibiting admixture, characterized by, Mixing the epoxy resin emulsion with the tertiary amine modified curing agent and reacting to obtain the tertiary amine modified CCUS corrosion resistant additive.

2. The method of preparing a tertiary amine modified CCUS corrosion inhibiting admixture of claim 1, wherein, The epoxy resin emulsion is a bisphenol A epoxy resin emulsion, a bisphenol F epoxy resin emulsion or a bisphenol S epoxy resin emulsion; the tertiary amine modified curing agent is dimethylaminopropylamine, dimethylaminopropyl methacrylamide or N,N-diethyl-1,3-propanediamine.

3. The method of claim 1, wherein the method is characterized by, The mass ratio of the epoxy resin emulsion to the tertiary amine modified curing agent is (40-50):(50-60).

4. The method of claim 1, wherein the method is characterized by, The reaction conditions are set as follows: reacting at 40-60℃ for 4-6h. 5.A tertiary amine modified CCUS corrosion resistant additive prepared by the preparation method of any one of claims 1-4.

6. A tertiary amine modified CCUS corrosion resistant cement admixture system characterized by, The raw materials include the tertiary amine modified CCUS corrosion resistant additive of claim 5, a fluid loss additive, a coagulant and a defoaming agent, and the mass ratio of the tertiary amine modified CCUS corrosion resistant additive to the fluid loss additive is 40-55:40-55.

7. The tertiary amine modified CCUS corrosion resistant cement admixture system of claim 6, wherein, The fluid loss additive is DRF-1S, G301 or SMAS-1; the coagulant is sodium sulfate, calcium sulfate or aluminum sulfate; and the defoaming agent is P80A, D70F or P805. 8.The application of the tertiary amine modified CCUS corrosion resistant additive of claim 5, or the tertiary amine modified CCUS corrosion resistant cement additive system of claim 6 or 7 in a CCUS corrosion resistant cement system.

9. A tertiary amine modified CCUS corrosion resistant cementitious system characterized by, The tertiary amine modified CCUS corrosion resistant cement additive system of claim 6 or 7 and oil well cement.

10. The tertiary amine modified CCUS corrosion resistant cementitious system of claim 9, wherein, The mass ratio of the tertiary amine modified CCUS corrosion resistant cement additive system to the oil well cement is (2-6):(94-98).

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