Plugging agent for resisting CO2 gas channeling and preparation method thereof

Abstract

The invention belongs to the technical field of oil-gas exploration and development, and discloses an anti-CO2 gas channeling plugging agent and a preparation method thereof.The preparation method comprises the steps that 100 parts by mass of epoxy resin and 12-16 parts by mass of diluent are added into a reaction container and mixed to be uniform, then deoxygenization is conducted, and reaction liquid is obtained; the preparation method comprises the following steps: mixing diethylenetriamine, methylene dicycloalkyl amine and m-phenylenediamine to obtain a curing agent, and then adjusting the pH value to 6-7 to obtain a mixed solution; and adding 15-20 parts of the mixed solution into the reaction solution, and reacting while heating to obtain the blocking agent for resisting CO2 gas channeling. The blocking agent for resisting CO2 gas channeling has the advantages of being good in fluidity, high in compressive strength, sufficient in toughness reserve, high in corrosion resistance and low in elastic modulus.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas exploration and development, relates to a CO2 gas leakage resistance plugging agent and a preparation method thereof, and is applied to the field of treatment of gas leakage problems occurring in CO2 flooding old wellbores. Background Art

[0002] As the main EOR technology, CO2 flooding has been widely used in North America, with an annual oil production of more than 16 million tons. In low permeability oil fields such as Jilin, the single well production can be increased by 2.3 times compared with water flooding, and the recovery rate in the test area can be increased by more than 10%. In the early stage, according to the needs of the reservoir, a CCUS (Carbon Capture, Utilization and Storage) pilot test was carried out in the old area. After a period of injection, gas appeared in oil wells at different layers, which seriously affected the CO2 recovery efficiency and safe and effective storage. Indoor studies have shown that saturated carbon dioxide corrosion on conventional cement sheaths reduces weight by 20% and strength by more than 45%, which has become one of the main factors affecting normal injection of CO2 flooding. Therefore, in view of the CO2 corrosive medium and the characteristics of a wide escape channel, it is necessary to propose a CO2 gas escape plugging agent and its preparation method to effectively solve the gas seepage phenomenon in oil wells at different layers caused by gas channeling outside the casing due to incomplete cement sheath and cement sheath holes caused by CO2 corrosion.

[0003] Current status of technology and existing problems:

[0004] Patent application No. 201811171792.3 discloses a cement slurry system and its preparation method, which is made of the following raw materials: G-grade oil well cement, high temperature resistant elastic material, high temperature resistant fluid loss agent, high temperature resistant inorganic anti-channeling emulsion, weighting agent, high temperature strength stabilizer, dispersant, slurry regulator, retarder and water. The system has good elastic properties in high temperature and high pressure environment and can effectively ensure interlayer sealing. However, the compressive strength of cement is greater than 18MPa / 7d, and the 60d compressive strength is greater than 30MPa.

[0005] Patent application number 202111087472.1 discloses a resin plugging agent and a preparation method thereof, which is made of the following raw materials: a main agent, a curing agent, a density regulator, a promoter, a hard inorganic material, and a coupling agent. The invention has good plugging effect, high adhesion strength, high compressive strength, and strong temperature resistance. Patent application number 201911152798.0 discloses a plugging agent, a preparation method, and its application, which is made of the following raw materials: preset grade cement, silica powder, anti-cracking agent, anti-channeling agent, water loss reducer, and retarder. The cement slurry system has excellent dispersibility, stability, and pumpability. It can not only effectively plug oil and water wells and prevent gas channeling in oil and water wells, but also has good pressure bearing capacity. The above two patents do not have acid resistance and anti-permeability properties. Summary of the invention

[0006] In order to overcome the problem in the prior art of how to achieve the purpose of blocking and preventing CO2 gas leakage from the wellbore under CCUS injection, storage and oil recovery conditions, the purpose of the present invention is to provide an anti-CO2 gas leakage blocking agent and a preparation method thereof.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0008] A CO2 gas escape resistance plugging agent comprises, by weight, 100 parts of epoxy resin, 12-16 parts of diluent and 15-20 parts of curing agent.

[0009] Furthermore, the type of the epoxy resin is E-03, E-12, E-20, E-35, E-42, E-44 or E-51.

[0010] Furthermore, the diluent is two of acetone, benzyl alcohol, ethanol, xylene and ethyl acetate.

[0011] Furthermore, the diluent is a mixture of 6-8 parts of acetone and 6-8 parts of xylene, measured by mass; or the diluent is a mixture of ethanol and xylene in a mass ratio of 7:3, or the diluent is a mixture of ethanol and ethyl acetate in a mass ratio of 7:3, or the diluent is a mixture of xylene and ethyl acetate in a mass ratio of 7:3.

[0012] Furthermore, the curing agent is a mixture of diethylenetriamine, methylenebicycloalkylamine and metaphenylenediamine in a mass ratio of 3:4:3.

[0013] A method for preparing a CO2 gas leakage-resistant plugging agent comprises the following steps:

[0014] 100 parts of epoxy resin and 12-16 parts of diluent are added into a reaction container by weight, mixed evenly, and then oxygen is discharged to obtain a reaction solution;

[0015] Diethylenetriamine, methylenebicycloalkylamine and m-phenylenediamine are mixed in a mass ratio of 3:4:3 to obtain a curing agent, and then the pH is adjusted to 6-7 to obtain a mixed solution;

[0016] 15-20 parts of the mixed solution are added to the reaction solution, and the mixture is reacted under heating to obtain a CO2 gas leakage resistance plugging agent.

[0017] Furthermore, the type of the epoxy resin is E-03, E-12, E-20, E-35, E-42, E-44 or E-51.

[0018] Furthermore, the diluent is a mixture of 6-8 parts of acetone and 6-8 parts of xylene, measured by mass; or the diluent is a mixture of ethanol and xylene in a mass ratio of 7:3, or the diluent is a mixture of ethanol and ethyl acetate in a mass ratio of 7:3, or the diluent is a mixture of xylene and ethyl acetate in a mass ratio of 7:3.

[0019] Furthermore, a NaOH solution with a mass fraction of 40% is used to adjust the pH to 6-7.

[0020] Furthermore, the reaction temperature is 65-75°C and the reaction time is 2-4h.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention adopts epoxy resin-based materials to replace traditional silicate gel materials, and synergizes the dilution effect of the diluent with the exothermic enhancement effect of the composite curing agent to prepare an anti-CO2 gas escape plugging agent with good fluidity, high compressive strength, sufficient toughness reserve, strong corrosion resistance and low elastic modulus, thereby overcoming the shortcomings of traditional silicate gel plugging agents such as poor fluidity, increased brittleness after corrosion and severe strength decay.

[0023] Furthermore, since the curing time range of the curing agent is relatively narrow and sensitive, the curing agent in the present invention is a mixture of divinyltriamine, methylenebicycloalkylamine and metaphenylenediamine in a mass ratio of 3:4:3. The mixture can be used as a composite curing agent to broaden the curing time range while reducing its sensitivity, and the curing strength is optimal.

[0024] Furthermore, the present invention uses a mixture of two of acetone, benzyl alcohol, ethanol, xylene and ethyl acetate as a diluent, which has a good dilution effect and effectively slows down the problem of volume shrinkage during curing.

[0025] In the present invention, the epoxy resin and the diluent are uniformly mixed, a curing agent for adjusting pH is added, and a reaction is carried out to obtain an anti-CO2 gas leakage plugging agent. The present invention uses less raw materials, and has a simple preparation method, readily available raw materials, and controllable costs, which is conducive to industrial production.

[0026] Furthermore, the purpose of reacting for 2-4 hours is to sufficiently reduce the viscosity so that the prepared plugging agent has stronger injectability. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 To prepare the process roadmap;

[0028] Figure 2 It is a process flow chart. DETAILED DESCRIPTION

[0029] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood.

[0030] The anti-CO2 gas leakage plugging agent of the present invention mainly comprises epoxy resin, diluent and curing agent. The components are composed as follows by mass: 100 parts of epoxy resin, 12-16 parts of diluent and 15-20 parts of curing agent. All of the above components are industrial products.

[0031] The types of epoxy resin are E-03, E-12, E-20, E-35, E-42, E-44 or E-51.

[0032] The diluent is two of acetone, benzyl alcohol, ethanol, xylene and ethyl acetate.

[0033] Preferably, the diluent is a mixture of acetone and benzyl alcohol in a mass ratio of (6-8): (6-8); or the diluent is a mixture of ethanol and xylene in a mass ratio of 7:3, or the diluent is a mixture of ethanol and ethyl acetate in a mass ratio of 7:3, or the diluent is a mixture of xylene and ethyl acetate in a mass ratio of 7:3. Using the mixture as the diluent has a good dilution effect and effectively slows down the problem of volume shrinkage during solidification.

[0034] The curing agent is a mixture of diethylenetriamine, methylenebicycloalkylamine and metaphenylenediamine in a mass ratio of 3:4:3. The mixture is used as a curing agent with the best curing strength.

[0035] The method for preparing the anti-CO2 gas leakage plugging agent as described above in the present invention comprises the following steps:

[0036] (1) 100 parts of epoxy resin and 12-16 parts of diluent are added to a four-necked flask equipped with a condenser, a stirrer, and a thermometer, and the inverse emulsion system is mechanically stirred for 30 minutes using a high-speed stirrer at room temperature, with a stirring speed of 20000 r / min-25000 r / min, nitrogen is introduced to deoxygenate the system, and the heating system is turned on and nitrogen is introduced to deoxygenate the system;

[0037] (2) Weigh 30 parts of diethylenetriamine, 40 parts of methylenebicycloalkylamine, and 30 parts of m-phenylenediamine, add them into a beaker containing a certain amount of deionized water, stir until completely dissolved, and then adjust the pH of the system to 6-7 with a 40% by mass NaOH solution to obtain a mixed solution;

[0038] (3) Weigh 15-20 portions of the mixed solution prepared in step (2) and place it in a constant pressure dropping funnel and place it on a four-necked flask;

[0039] (4) After the temperature of the system in step (1) rises to 65-75°C and is kept at this temperature for 15 minutes, the mixed solution is added dropwise, and after the addition is completed within 30 minutes, the mixture is reacted at 65-75°C under continuous stirring for 2.0-4.0 hours to obtain an oily anti-CO2 gas leakage plugging agent. The purpose of the reaction in the present invention is to fully reduce the viscosity so that the prepared plugging agent has stronger injectability.

[0040] Example 1

[0041] See also Figure 1 and Figure 2 A method for preparing a CO2 gas leakage-resistant plugging agent comprises the following steps:

[0042] (1) 100 parts of epoxy resin E-44, 6 parts of acetone and 8 parts of benzyl alcohol were weighed by weight and added into a four-necked flask equipped with a condenser, a stirrer and a thermometer. The inverse emulsion system was mechanically stirred for 30 minutes at room temperature using a high-speed stirrer at a stirring speed of 20,000 r / min. Nitrogen was introduced to deoxygenate the system. The heating system was turned on and nitrogen was introduced to deoxygenate the system.

[0043] (2) Weigh 30 parts of diethylenetriamine (CA-1), 40 parts of methylenebicycloalkylamine (CA-2), and 30 parts of metaphenylenediamine (CA-3) into a beaker containing a certain amount of deionized water, stir until completely dissolved, and then adjust the pH of the system to 6 with a 40% by mass NaOH solution to obtain a mixed solution;

[0044] (3) Weigh 16 portions of the mixed solution prepared in step (2) and place them in a constant pressure dropping funnel and place it on a four-necked flask;

[0045] (4) After the temperature of the system in step (1) rises to 70°C and is kept at this temperature for 15 minutes, the mixed solution is added dropwise. After the addition is completed within 30 minutes, stirring is continued for 2.0 hours to obtain an oily anti-CO2 gas leakage plugging agent.

[0046] The anti-CO2 gas leakage plugging agent prepared by the present invention has the following advantages:

[0047] (1) The anti-CO2 gas leakage plugging agent prepared by the present invention has good injectability.

[0048] At room temperature, the viscosity of the plugging agent ranges from 62 to 110 mPa.s. Compared with the plugging agents used on the market, the viscosity reduction rate is as high as 72.5%, which can achieve effective plugging of micro-cracks of different sizes.

[0049] Table 1 Plugging agent viscosity test at different temperatures

[0050]

[0051]

[0052] (2) The anti-CO2 gas leakage plugging agent has excellent pressure resistance and flexibility.

[0053] The 24h compressive strength of the cured plugging agent is as high as 45.6MPa, and the elastic modulus is reduced to 3.62GPa. Compared with conventional plugging agents, the elastic modulus is reduced by 60.5%, the Poisson's ratio is increased by 71.4%, and the deformability is increased by 523%. It has extremely strong compressive resistance and impact toughness.

[0054] Table 2 Comparison of parameters between conventional plugging agents and anti-CO2 gas leakage plugging agents

[0055] Test items Conventional plugging agent <![CDATA[Anti-CO2 gas channeling plugging agent]]> Young's modulus / Gpa 5.95 4.61 Flexibility / Gpa-1 0.168 0.217 Poisson's ratio 0.366 0.384 Bulk elastic modulus / Gpa 7.21 3.62 Volume compliance / Gpa-1 0.139 0.152

[0056] (3) The anti-CO2 gas leakage plugging agent has good resistance to acidic medium corrosion.

[0057] The solidified body of the plugging agent has high density, strong non-permeability and a permeability of 0mD; compared with conventional plugging agents, the solidified body has strong stability, and the compressive strength decay rate is reduced by more than 86.48% after 60 days of CO2 corrosion curing.

[0058] Table 3 Comparison of corrosion compressive strength decline of different plugging agents

[0059]

[0060] The present invention replaces the traditional silicate gel material with epoxy resin-based material, cooperates with the dilution effect of acetone / benzyl alcohol and the heat release enhancement effect of the composite curing agent, and prepares a plugging agent with good fluidity, high compressive strength, sufficient toughness reserve, strong corrosion resistance, and low elastic modulus to resist CO2 gas leakage, thereby overcoming the shortcomings of the traditional silicate gel plugging agent, such as poor fluidity, increased brittleness after corrosion, and severe strength decay. The preparation method is simple, the raw materials are easily available, and the cost is controllable.

[0061] Example 2

[0062] A method for preparing a CO2 gas leakage-resistant plugging agent comprises the following steps:

[0063] (1) 100 parts of epoxy resin E-03, 8 parts of acetone and 7 parts of benzyl alcohol were weighed by weight and added into a four-necked flask equipped with a condenser, a stirrer and a thermometer. The inverse emulsion system was mechanically stirred for 30 minutes at room temperature using a high-speed stirrer at a stirring speed of 20,000 r / min. Nitrogen was introduced to deoxygenate the system. The heating system was turned on and nitrogen was introduced to deoxygenate the system.

[0064] (2) Weigh 30 parts of diethylenetriamine (CA-1), 40 parts of methylenebicycloalkylamine (CA-2), and 30 parts of metaphenylenediamine (CA-3) into a beaker containing a certain amount of deionized water, stir until completely dissolved, and then adjust the pH of the system to 7 with a 40% by mass NaOH solution to obtain a mixed solution;

[0065] (3) Weigh 15 portions of the mixed solution prepared in step (2) and place them in a constant pressure dropping funnel and place it on a four-necked flask;

[0066] (4) After the temperature of the system in step (1) rises to 65°C and is kept at this temperature for 15 minutes, the mixed solution is added dropwise. After the addition is completed within 30 minutes, stirring is continued for 2.0 hours to obtain an oily anti-CO2 gas leakage plugging agent.

[0067] Example 3

[0068] A method for preparing a CO2 gas leakage-resistant plugging agent comprises the following steps:

[0069] (1) 100 parts of epoxy resin E-12, 7 parts of acetone and 6 parts of benzyl alcohol were weighed by weight and added into a four-necked flask equipped with a condenser, a stirrer and a thermometer. The inverse emulsion system was mechanically stirred for 30 minutes at room temperature using a high-speed stirrer at a stirring speed of 25000 r / min. Nitrogen was introduced to deoxygenate the system. The heating system was turned on and nitrogen was introduced to deoxygenate the system.

[0070] (2) Weigh 30 parts of diethylenetriamine (CA-1), 40 parts of methylenebicycloalkylamine (CA-2), and 30 parts of metaphenylenediamine (CA-3) into a beaker containing a certain amount of deionized water, stir until completely dissolved, and then adjust the pH of the system to 6 with a 40% by mass NaOH solution to obtain a mixed solution;

[0071] (3) Weigh 20 portions of the mixed solution prepared in step (2) and place them in a constant pressure dropping funnel and place it on a four-necked flask;

[0072] (4) After the temperature of the system in step (1) rises to 75°C and is kept at this temperature for 15 minutes, the mixed solution is added dropwise. After the addition is completed within 30 minutes, stirring is continued for 2.0 hours to obtain an oily anti-CO2 gas leakage plugging agent.

[0073] Example 4

[0074] A method for preparing a CO2 gas leakage-resistant plugging agent comprises the following steps:

[0075] (1) 100 parts of epoxy resin E-20, 6 parts of acetone and 6 parts of benzyl alcohol were weighed by weight and added into a four-necked flask equipped with a condenser, a stirrer and a thermometer. The inverse emulsion system was mechanically stirred for 30 minutes at room temperature using a high-speed stirrer at a stirring speed of 22000 r / min. Nitrogen was introduced to deoxygenate the system. The heating system was turned on and nitrogen was introduced to deoxygenate the system.

[0076] (2) Weigh 30 parts of diethylenetriamine (CA-1), 40 parts of methylenebicycloalkylamine (CA-2), and 30 parts of metaphenylenediamine (CA-3) into a beaker containing a certain amount of deionized water, stir until completely dissolved, and then adjust the pH of the system to 7 with a 40% by mass NaOH solution to obtain a mixed solution;

[0077] (3) Weigh 18 portions of the mixed solution prepared in step (2) and place them in a constant pressure dropping funnel and place it on a four-necked flask;

[0078] (4) After the temperature of the system in step (1) rises to 68°C and is kept at this temperature for 15 minutes, the mixed solution is added dropwise. After the addition is completed within 30 minutes, stirring is continued for 2.0 hours to obtain an oily anti-CO2 gas leakage plugging agent.

[0079] Example 5

[0080] A method for preparing a CO2 gas leakage-resistant plugging agent comprises the following steps:

[0081] (1) 100 parts of epoxy resin E-35, 8 parts of acetone and 8 parts of benzyl alcohol were weighed by weight and added into a four-necked flask equipped with a condenser, a stirrer and a thermometer. The inverse emulsion system was mechanically stirred for 30 minutes at room temperature using a high-speed stirrer at a stirring speed of 23000 r / min. Nitrogen was introduced to deoxygenate the system. The heating system was turned on and nitrogen was introduced to deoxygenate the system.

[0082] (2) Weigh 30 parts of diethylenetriamine (CA-1), 40 parts of methylenebicycloalkylamine (CA-2), and 30 parts of metaphenylenediamine (CA-3) into a beaker containing a certain amount of deionized water, stir until completely dissolved, and then adjust the pH of the system to 6 with a 40% by mass NaOH solution to obtain a mixed solution;

[0083] (3) Weigh 17 portions of the mixed solution prepared in step (2) and place them in a constant pressure dropping funnel and place them on a four-necked flask;

[0084] (4) After the temperature of the system in step (1) rises to 70°C and is kept at this temperature for 15 minutes, the mixed solution is added dropwise. After the addition is completed within 30 minutes, stirring is continued for 2.0 hours to obtain an oily anti-CO2 gas leakage plugging agent.

[0085] Example 6

[0086] A method for preparing a CO2 gas leakage-resistant plugging agent comprises the following steps:

[0087] (1) 100 parts of epoxy resin E-42 and 16 parts of diluent (a mixture of ethanol and xylene in a mass ratio of 7:3) were weighed and added into a four-necked flask equipped with a condenser, a stirrer, and a thermometer. The inverse emulsion system was mechanically stirred for 30 minutes at room temperature using a high-speed stirrer at a stirring speed of 24000 r / min. Nitrogen was introduced to deoxygenate the system. The heating system was turned on and nitrogen was introduced to deoxygenate the system.

[0088] (2) Weigh 30 parts of diethylenetriamine (CA-1), 40 parts of methylenebicycloalkylamine (CA-2), and 30 parts of metaphenylenediamine (CA-3) into a beaker containing a certain amount of deionized water, stir until completely dissolved, and then adjust the pH of the system to 7 with a 40% by mass NaOH solution to obtain a mixed solution;

[0089] (3) Weigh 15 portions of the mixed solution prepared in step (2) and place them in a constant pressure dropping funnel and place it on a four-necked flask;

[0090] (4) After the temperature of the system in step (1) rises to 73°C and is kept at this temperature for 15 minutes, the mixed solution is added dropwise. After the addition is completed within 30 minutes, stirring is continued for 2.5 hours to obtain an oily anti-CO2 gas leakage plugging agent.

[0091] Example 7

[0092] A method for preparing a CO2 gas leakage-resistant plugging agent comprises the following steps:

[0093] (1) 100 parts of epoxy resin E-51 and 12 parts of diluent (a mixture of ethanol and ethyl acetate in a mass ratio of 7:3) were weighed and added into a four-necked flask equipped with a condenser, a stirrer, and a thermometer. The inverse emulsion system was mechanically stirred for 30 minutes at room temperature using a high-speed stirrer at a stirring speed of 20,000 r / min-25,000 r / min. Nitrogen was introduced to deoxygenate the system. The heating system was turned on and nitrogen was introduced to deoxygenate the system.

[0094] (2) Weigh 30 parts of diethylenetriamine (CA-1), 40 parts of methylenebicycloalkylamine (CA-2), and 30 parts of metaphenylenediamine (CA-3) into a beaker containing a certain amount of deionized water, stir until completely dissolved, and then adjust the pH of the system to 7 with a 40% by mass NaOH solution to obtain a mixed solution;

[0095] (3) Weigh 20 portions of the mixed solution prepared in step (2) and place them in a constant pressure dropping funnel and place it on a four-necked flask;

[0096] (4) After the temperature of the system in step (1) rises to 72°C and is kept at this temperature for 15 minutes, the mixed solution is added dropwise. After the addition is completed within 30 minutes, stirring is continued for 3.0 hours to obtain an oily anti-CO2 gas leakage plugging agent.

[0097] Example 8

[0098] A method for preparing a CO2 gas leakage-resistant plugging agent comprises the following steps:

[0099] (1) 100 parts of epoxy resin E-44 and 14 parts of diluent (a mixture of xylene and ethyl acetate in a mass ratio of 7:3) were weighed and added into a four-necked flask equipped with a condenser, a stirrer, and a thermometer. The inverse emulsion system was mechanically stirred for 30 minutes at room temperature using a high-speed stirrer at a stirring speed of 21000 r / min. Nitrogen was introduced to deoxygenate the system. The heating system was turned on and nitrogen was introduced to deoxygenate the system.

[0100] (2) Weigh 30 parts of diethylenetriamine (CA-1), 40 parts of methylenebicycloalkylamine (CA-2), and 30 parts of metaphenylenediamine (CA-3) into a beaker containing a certain amount of deionized water, stir until completely dissolved, and then adjust the pH of the system to 6 with a 40% by mass NaOH solution to obtain a mixed solution;

[0101] (3) Weigh 19 portions of the mixed solution prepared in step (2) and place them in a constant pressure dropping funnel and place it on a four-necked flask;

[0102] (4) After the temperature of the system in step (1) rises to 76°C and is kept at this temperature for 15 minutes, the mixed solution is added dropwise. After the addition is completed within 30 minutes, stirring is continued for 4.0 hours to obtain an oily anti-CO2 gas leakage plugging agent.

[0103] The above description is only for the best embodiment of the present invention, but it should not be understood as limiting the claims. The present invention is not limited to the above embodiments, and its specific structure is allowed to be changed. However, all changes made within the protection scope of the independent claims of the present invention are within the protection scope of the present invention.

[0104] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

Claims

1. A plugging agent for preventing CO2 gas leakage, characterized in that: Calculated by mass, it includes 100 parts of epoxy resin, 12-16 parts of diluent and 15-20 parts of curing agent.

2. The anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The types of epoxy resin are E-03, E-12, E-20, E-35, E-42, E-44 or E-51.

3. The anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The diluent is two of acetone, benzyl alcohol, ethanol, xylene and ethyl acetate.

4. The anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: Calculated by mass, the diluent is a mixture of 6-8 parts of acetone and 6-8 parts of xylene; or the diluent is a mixture of ethanol and xylene in a mass ratio of 7:3, or the diluent is a mixture of ethanol and ethyl acetate in a mass ratio of 7:3, or the diluent is a mixture of xylene and ethyl acetate in a mass ratio of 7:

3.

5. The anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The curing agent is a mixture of diethylenetriamine, methylenebicycloalkylamine and metaphenylenediamine in a mass ratio of 3:4:

3.

6. A method for preparing a CO2 gas leakage-resistant plugging agent, characterized in that: The following steps are involved: 100 parts of epoxy resin and 12-16 parts of diluent are added into a reaction container by weight, mixed evenly, and then oxygen is discharged to obtain a reaction solution; Mixing divinyltriamine, methylenebicycloalkylamine and metaphenylenediamine to obtain a curing agent, and then adjusting the pH to 6-7 to obtain a mixed solution; 15-20 parts of the mixed solution are added to the reaction solution, and the mixture is reacted under heating to obtain a CO2 gas leakage resistance plugging agent.

7. The method for preparing the anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The types of epoxy resin are E-03, E-12, E-20, E-35, E-42, E-44 or E-51.

8. The method for preparing the anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: Calculated by mass, the diluent is a mixture of 6-8 parts of acetone and 6-8 parts of xylene; or the diluent is a mixture of ethanol and xylene in a mass ratio of 7:3, or the diluent is a mixture of ethanol and ethyl acetate in a mass ratio of 7:3, or the diluent is a mixture of xylene and ethyl acetate in a mass ratio of 7:

3.

9. The method for preparing the anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The mass ratio of diethylenetriamine, methylenebicycloalkylamine and metaphenylenediamine is 3:4:3; and a NaOH solution with a mass fraction of 40% is used to adjust the pH to 6-7.

10. The method for preparing the anti-CO2 gas leakage plugging agent according to claim 1, characterized in that: The reaction temperature is 65-75°C and the reaction time is 2-4h.

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