A self-generating gas reaming sand consolidation resin system and a preparation method thereof

Abstract

The application belongs to the technical field of oil field chemistry, and particularly relates to a self-gas hole-expanding sand-fixing resin system and a preparation method thereof. The self-gas hole-expanding sand-fixing resin system provided by the application comprises resin, a curing agent, a control agent, a reinforcing agent, a gas-producing agent and water. The self-gas hole-expanding sand-fixing resin system has low viscosity and does not solidify under low-temperature conditions, can be injected in an integrated manner, is convenient to use, and the gas-producing agent produces a large amount of harmless gas (nitrogen) under formation conditions, retains a seepage passage, and has a high retention rate of the permeability of a consolidated body.

Description

Technical Field

[0001] This invention belongs to the field of oilfield chemical technology, specifically relating to a self-generating resin system for pore expansion and sand fixation and its preparation method. Background Technology

[0002] With the further development of oil fields, sand production problems are becoming increasingly serious. Mechanical sand control cannot fundamentally solve the problem of reservoir sand production; it has poor sand-blocking effect on fine sand, cannot consolidate sand particles, and has a short effective period. Chemical sand control technology has advantages such as strong formation adaptability, ability to block fine sand, no need for mechanical devices, and simple construction process. However, the current chemical sand control system has high density and high viscosity, which seriously affects the pumpability of the chemical sand control system into the formation. Moreover, it has problems such as complex construction and low retention rate of solidified body permeability during oil field operations.

[0003] Chinese invention patent application number 201510704656.6 discloses a novel low-temperature coating sand, composed of two components, A and B, in a 1:1 weight ratio. Component A includes quartz sand, binder, coupling agent, dispersant, and accelerator; component B includes quartz sand, curing agent, coupling agent, dispersant, and accelerator. The invention offers the following advantages: rapid curing speed, high early strength, and a wide applicable oil layer temperature range. The product can achieve high early strength within 24 hours at temperatures ranging from 45-260℃. The setting time is short. However, the resulting solidified body exhibits low permeability retention.

[0004] Chinese invention patent application number 201010004611.5 discloses a coated sand solidification system suitable for sand control in low-temperature oil reservoirs. This system is a high-reactivity solidification system formed by mixing low-temperature coated sand with a composite phenolic-epoxy resin binder and a water-soluble curing agent, operating in both aqueous and low-temperature environments. Under the action of the water-soluble curing agent, the low-temperature coated sand can solidify within a temperature range of 30–50°C. The resulting solidified body exhibits high compressive strength and permeability retention, as well as strong resistance to temperature, aging, and erosion, meeting the requirements for sand control in low-temperature oil reservoirs. However, this sand-fixing system solidifies at low temperatures. For sand control in filling depleted formations, the solidification occurs before injection into the formation; therefore, it cannot be directly injected into the formation for formation sand fixation. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a self-generating resin system for expanding pores and consolidating sand, and its preparation method.

[0006] Specifically, the self-generating pore-expanding sand-fixing resin system provided by the present invention includes: resin, curing agent, control agent, reinforcing agent, gas-generating agent, and water.

[0007] The above-mentioned self-generating pore-expanding sand-fixing resin system, based on a total weight of 100 parts, includes: 16-20 parts resin, 10-14 parts curing agent, 2-3 parts control agent, 1-3 parts reinforcing agent, 5-7 parts gas-generating agent, and the balance being water.

[0008] The above-mentioned self-generating pore-expanding sand-fixing resin system, based on a total weight of 100 parts, includes: 18 parts resin, 12 parts curing agent, 2.5 parts control agent, 2 parts reinforcing agent, 6 parts gas-generating agent, and the balance being water.

[0009] The resin system for self-generating pore-expanding and sand-fixing described above is a guaiacol / maleic anhydride copolymer.

[0010] In the above-mentioned self-generating pore-expanding and sand-fixing resin system, the curing agent is 4,4-diaminodiphenylmethane.

[0011] In the above-mentioned self-generating resin system for expanding pores and fixing sand, the control agent is citric acid.

[0012] In the above-mentioned self-generating pore-expanding and sand-fixing resin system, the reinforcing agent is polyetheramine D230.

[0013] In the above-mentioned self-generating resin system for expanding pores and consolidating sand, the gas-generating agent is prepared by the following method:

[0014] (1) Microporous silica microspheres were added to a mixture of ethanol and water, KH-550 was added to the microporous silica microsphere suspension, and the mixture was ultrasonically treated to obtain a mixture;

[0015] (2) The mixture was stirred, filtered and dried to obtain microporous silica microspheres-KH-550;

[0016] (3) Add benzenesulfonyl hydrazine to N,N-dimethylformamide solution, add the microporous silica microspheres-KH-550, and stir;

[0017] (4) Discard the supernatant, collect the precipitate, wash it with methanol and filter it to obtain spherical solid particles of gas-generating agent.

[0018] In the above-mentioned self-generating resin system for expanding pores and fixing sand, the weight ratio of the microporous silica microspheres, the KH-550 and the benzenesulfonyl hydrazine is (0.9-1):(1.9-2.1):(0.95-1.05).

[0019] On the other hand, the present invention provides a method for preparing the above-mentioned self-generating pore-expanding and sand-fixing resin system, comprising: first mixing and stirring the resin and curing agent in proportion, then adding the control agent, reinforcing agent, gas-generating agent and water in proportion, mixing and stirring evenly to obtain the self-generating pore-expanding and sand-fixing resin system.

[0020] The technical solution of the present invention has the following beneficial effects:

[0021] (1) The resin system for self-generating pore expansion and sand consolidation of the present invention has low viscosity and does not solidify under low temperature conditions. It can be injected in an "integrated" manner, which is convenient for construction. Furthermore, the gas-generating agent generates a large amount of harmless gas (nitrogen) under formation conditions, retains the seepage channel, and has a high permeability retention rate of the solidified body.

[0022] (2) The present invention uses curing agent 4,4-diaminodiphenylmethane and reinforcing agent polyetheramine D230 to cure the resin, so that the strength of the solidified body can reach 6.68 MPa.

[0023] (3) The present invention reacts at a formation temperature of about 90°C and generates N2 that is harmless to the formation to expand the pores. Some seepage channels are retained, and the permeability retention rate can reach more than 90%, thereby achieving low damage to the formation. Detailed Implementation

[0024] To fully understand the purpose, features, and effects of this invention, the following detailed embodiments are provided. Except as described below, the process methods of this invention employ conventional methods or apparatus in the art. Unless otherwise specified, the terms and expressions used below have the meanings commonly understood by those skilled in the art.

[0025] When a range of values ​​is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0026] Specifically, a self-generating resin system for expanding pores and fixing sand includes: resin, curing agent, control agent, reinforcing agent, gas-generating agent, and water.

[0027] In some preferred embodiments, the resin is a guaiacol / maleic anhydride copolymer, the curing agent is 4,4-diaminodiphenylmethane, the control agent is citric acid, and the reinforcing agent is polyetheramine D230.

[0028] In the self-generating pore-expanding sand-fixing resin system of this invention, the guaiacol / maleic anhydride binary copolymer exhibits low brittleness, toughness, and resistance to cracking after curing, while also being non-shrinking, non-deforming, and possessing strength. As the main component, it serves as a skeleton material with excellent mechanical and adhesive properties. 4,4-Diaminodiphenylmethane plays a curing role in this system, and the curing time can be controlled by adjusting the amount of citric acid added. The reinforcing agent, polyetheramine D230, enhances the bonding of clay, thereby improving compressive strength. The hydroxyl groups of the resin and sand particles interact, adsorbing the curing agent and resin, resulting in a curing reaction that forms a thermosetting material with certain chemical activity and bonding strength. This material binds the sand particles, achieving the purpose of sand fixation. After adsorption, curing occurs under specific temperature conditions. The benzenesulfonyl hydrazine portion of the gas-generating agent begins to oxidize and decompose at a formation temperature of approximately 90°C, producing a large amount of N2, which occupies some seepage channels and is not solidified. The reaction simultaneously generates a large amount of heat, promoting partial curing of the resin. The synergistic effect among the components gives the self-generating pore-expanding and sand-fixing resin system advantages such as low viscosity, non-curing at low temperatures, and high permeability retention of the solidified body.

[0029] In some preferred embodiments, the self-generating pore-expanding sand-fixing resin system of the present invention, based on a total weight of 100 parts, comprises: 16-20 parts resin, 10-14 parts curing agent, 2-3 parts control agent, 1-3 parts reinforcing agent, 5-7 parts gas-generating agent, and the balance being water.

[0030] In practice, too much resin increases costs, while too little resin reduces strength; too much curing agent increases costs, while too little curing agent reduces strength; too little control agent results in a short curing time, while too much control agent results in a long curing time and reduced strength; too much reinforcing agent increases costs, while too little reinforcing agent reduces strength; too much gas-generating agent reduces strength, while too little gas-generating agent reduces gas production and decreases permeability retention.

[0031] More preferably, the self-generating pore-expanding sand-fixing resin system of the present invention, based on a total weight of 100 parts, comprises: 18 parts resin, 12 parts curing agent, 2.5 parts control agent, 2 parts reinforcing agent, 6 parts gas-generating agent, and the balance being water.

[0032] In some preferred embodiments, the resin is prepared by the following method:

[0033] (1) Dissolve guaiacol in dichloroethane, add aluminum trichloride and succinic anhydride in sequence under ice-water bath, and heat to carry out the reaction;

[0034] (2) After the reaction is complete, hydrochloric acid is slowly added, and the product is obtained by filtration, recrystallization and drying.

[0035] (3) Dissolve the first intermediate product in distilled water, add hydrazine hydrate, heat and carry out the reaction;

[0036] (4) After the reaction is complete, cool and adjust the pH to neutral, then filter, wash and dry to obtain the second intermediate product;

[0037] (5) Dissolve the second intermediate product and sodium m-nitrobenzenesulfonate in an alkaline solution, heat, and react.

[0038] (6) After the reaction is complete, adjust the pH to neutral, and obtain the resin by filtration, washing and drying.

[0039] In some preferred embodiments, the gas-generating agent is prepared by the following method: (1) adding microporous silica microspheres to a mixture of ethanol and water, adding KH-550 to the microporous silica microsphere suspension, and ultrasonically treating to obtain a mixture; (2) stirring, filtering, and drying the mixture to obtain microporous silica microspheres-KH-550; (3) adding benzenesulfonyl hydrazine to an N,N-dimethylformamide solution, adding the microporous silica microspheres-KH-550, and stirring; (4) discarding the supernatant, collecting the precipitate, washing with methanol, and filtering to obtain spherical solid particle gas-generating agent.

[0040] The weight ratio of the microporous silica microspheres, the KH-550 and the benzenesulfonyl hydrazine is (0.9-1):(1.9-2.1):(0.95-1.05).

[0041] The microporous silica microspheres were prepared by the following method:

[0042] (1) Dissolve nonylphenol ethoxylated decamethyl ether in water, and then add citric acid to obtain the first mixture;

[0043] (2) Dissolve n-octadecane in ethanol, slowly add it to the first mixture while stirring, and then stir to obtain the second mixture;

[0044] (3) Gradually add silicon dioxide into deionized water and heat while stirring;

[0045] (4) Heat or let stand until the reaction is complete, then filter, wash and dry to obtain the product.

[0046] On the other hand, the present invention also provides a method for preparing a resin system for self-generating pore expansion and sand fixation, comprising: first mixing and stirring the resin and curing agent in proportion, then adding the control agent, reinforcing agent, gas generating agent and water in proportion, mixing and stirring evenly to obtain the resin system for self-generating pore expansion and sand fixation.

[0047] Example

[0048] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments, unless otherwise specified, are performed according to conventional methods and conditions.

[0049] The raw materials used in the examples and comparative examples are from the following sources:

[0050] Polyetheramine D230: Industrial grade, Ousbang New Materials Co., Ltd.

[0051] Citric acid: AR grade, Aladdin Biochemical Technology Co., Ltd.

[0052] KH-550: AR grade, Guangzhou Yuanda New Materials Co., Ltd.

[0053] Benzenesulfonyl hydrazine: AR grade, McLean Biotech Co., Ltd.

[0054] 4,4-Diaminodiphenylmethane: AR grade, McLean Biotech Co., Ltd.

[0055] The preparation method of guaiacol / maleic anhydride binary copolymer is as follows:

[0056] Add 30g of guaiacol and 380ml of dichloroethane to a three-necked flask equipped with a mechanical stirrer, and stir at room temperature until fully dissolved. Then transfer the system to an ice-water bath, maintaining the temperature at 0℃, and slowly add 83.3g of anhydrous aluminum trichloride, continuing stirring for 20min. Next, slowly add 25g of succinic anhydride to the system, and continue stirring at 0℃ for 30min. Then slowly raise the temperature to 30℃ and react at this temperature for 8h. After the reaction is complete, pour the system into ice water, and add 20ml of concentrated hydrochloric acid dropwise. Collect the precipitate by vacuum filtration, and recrystallize the crude product in distilled water. After drying, a white crystalline first intermediate product is obtained. ② Add 22.5g of the first intermediate product obtained in the previous step and 150ml of distilled water to a three-necked flask equipped with a mechanical stirrer and reflux condenser. Heat to reflux until the reactants are completely dissolved. Then, add 15.6 g of 80% pure hydrazine hydrate dropwise to the system and continue the reaction under reflux for 2.5 h. After the reaction is complete, pour the mixture into a beaker, cool to room temperature, and then adjust the pH of the system to 7 with concentrated hydrochloric acid. Filter, collect the product on the filter cake, wash three times with distilled water, and dry to obtain the pale yellow product, the second intermediate. ③ In a three-necked flask equipped with a mechanical stirrer and a reflux condenser, add 11 g of the second intermediate, 14 g of sodium m-nitrobenzenesulfonate, and 550 ml of a 0.5 mol / L sodium hydroxide aqueous solution. Heat to reflux and react for 10 h. After the reaction is complete, pour the system into a beaker, cool to room temperature, and add concentrated hydrochloric acid dropwise until the pH of the system is 7. Filter, collect the product on the filter cake, wash three times with distilled water, and dry to obtain the final yellow product, guaiacol / maleic anhydride copolymer.

[0057] The preparation method of microporous silica microspheres is as follows:

[0058] First, dissolve 0.3 g of nonylphenol ethoxylated decamethyl ether in 60 g of deionized water and stir for 0.5 h to ensure complete dissolution of NP-10. Then, add 5 mL of 1 mol / L citric acid while stirring at room temperature. Dissolve 1 g of n-octadecane in 25 mL of ethanol and slowly add it to the acidified nonylphenol ethoxylated decamethyl ether solution while stirring. The solution immediately turns into a milky white emulsion. Stir the emulsion vigorously at 50 °C for 1 hour. Finally, add 0.8 g of silica to 4 g of deionized water and stir vigorously at 50 °C, adding it gradually. This process adjusts the pH of the solution to 4-5. Then, heat in a 70 °C oven for 4 h or let stand at room temperature for 24 h, followed by heating in a 70 °C oven for 12 h. Filter the white precipitate, wash three times with deionized water, and dry overnight in a vacuum oven at 50 °C. The final product is obtained.

[0059] Gas-generating agent: prepared in the laboratory

[0060] (1) Add 1g of microporous silica microspheres to a mixture of ethanol and water (85ml ethanol and 15ml water), add 2ml KH-550 to the microporous silica microsphere suspension, and sonicate to obtain a mixture; (2) Stir, filter and dry the mixture to obtain microporous silica microspheres-KH-550; (3) Add benzenesulfonyl hydrazine to 15ml N,N-dimethylformamide solution to obtain a 0.4mol / L solution, then add the microporous silica microspheres-KH-550 and stir for 24h; (4) Discard the supernatant, collect the precipitate, wash with methanol and filter to obtain spherical solid particles gas generator.

[0061] Example 1

[0062] A mixture of 16 parts guaiacol / maleic anhydride binary copolymer and 10 parts 4,4-diaminodiphenylmethane was stirred until homogeneous. Then, 2.5 parts citric acid, 2 parts polyetheramine D230, 6 parts gas-generating agent, and the remainder water were added and stirred until homogeneous. The total weight of the above components was 100 parts. The mixture was then stirred until homogeneous to obtain a self-generating resin system for expanding pores and consolidating sand.

[0063] The system was injected into a sand column and aged at 90°C. The permeability retention and compressive strength were observed. The results are shown in Table 1.

[0064] Table 1

[0065]

[0066] Example 2

[0067] Mix 18 parts of guaiacol / maleic anhydride binary copolymer and 12 parts of 4,4-diaminodiphenylmethane in a specific ratio until homogeneous. Then add 2.5 parts of citric acid, 2 parts of polyetheramine D230, 6 parts of gas-generating agent, and the remainder is water in a specific ratio. Mix and stir until homogeneous. The total weight of the above components is 100 parts. Mix the two mixtures again until homogeneous to obtain a self-generating resin system for expanding pores and consolidating sand.

[0068] The system was injected into a sand column and aged at 90°C. The permeability and compressive strength were observed. The results are shown in Table 2.

[0069] Table 2

[0070]

[0071] Example 3

[0072] Mix 18 parts of guaiacol / maleic anhydride binary copolymer and 14 parts of 4,4-diaminodiphenylmethane in a specific ratio until homogeneous. Then add 2.5 parts of citric acid, 2 parts of polyetheramine D230, 6 parts of gas-generating agent, and the remainder is water in a specific ratio. Mix and stir until homogeneous. The total weight of the above components is 100 parts. Mix the two mixtures again until homogeneous to obtain a self-generating resin system for expanding pores and consolidating sand.

[0073] The system was injected into a sand column and aged at 90°C. The permeability and compressive strength were observed. The results are shown in Table 3.

[0074] Table 3

[0075]

[0076] Comparative Example 1

[0077] Mix 18 parts of guaiacol / maleic anhydride binary copolymer and 12 parts of 4,4-diaminodiphenylmethane in a specific ratio until homogeneous. Then add 2.5 parts of citric acid, 2 parts of polyetheramine D230, and the remainder water in a specific ratio, and mix thoroughly. The total weight of the above components is 100 parts. Mix the two mixtures thoroughly again to obtain a self-generating resin system for expanding pores and fixing sand.

[0078] The system was injected into a sand column and aged at 90°C. The permeability and compressive strength were observed. The results are shown in Table 4.

[0079] Table 4

[0080]

[0081] Comparative Example 2

[0082] Mix 18 parts of guaiacol / maleic anhydride binary copolymer and 12 parts of 4,4-diaminodiphenylmethane in a specific ratio until homogeneous. Then add 2.5 parts of citric acid, 2 parts of polyetheramine D230, 12 parts of gas-generating agent, and the remainder is water in a specific ratio. Mix and stir until homogeneous. The total weight of the above components is 100 parts. Mix the two mixtures again until homogeneous to obtain a self-generating resin system for expanding pores and consolidating sand.

[0083] The system was injected into a sand column and aged at 90°C. The permeability and compressive strength were observed. The results are shown in Table 5.

[0084] Table 5

[0085]

[0086] Comparative Example 3

[0087] 24 parts of guaiacol / maleic anhydride binary copolymer and 18 parts of 4,4-diaminodiphenylmethane were mixed and stirred evenly in a certain proportion. Then, 2.5 parts of citric acid, 2 parts of polyetheramine D230, 6 parts of gas-generating agent, and the balance being water were added in a certain proportion and mixed and stirred evenly. The total weight of the above components was 100 parts. The two were then mixed and stirred evenly to obtain a self-generating pore-expanding and sand-fixing resin system.

[0088] The system was injected into a sand column and aged at 90°C. The permeability and compressive strength were observed. The results are shown in Table 6.

[0089] Table 6

[0090]

[0091]

[0092] Comparative Example 4

[0093] Mix 18 parts of guaiacol / maleic anhydride binary copolymer and 12 parts of triethylenetetramine in a specific ratio until homogeneous. Then add 2.5 parts of citric acid, 2 parts of polyetheramine D230, 6 parts of gas-generating agent, and the remainder is water in a specific ratio. Mix and stir until homogeneous. The total weight of the above components is 100. Mix the two mixtures again until homogeneous to obtain a self-generating resin system for expanding pores and consolidating sand.

[0094] The system was injected into a sand column and aged at 90°C. The permeability and compressive strength were observed. The results are shown in Table 7.

[0095] Table 7

[0096]

[0097] Comparative Example 5

[0098] Mix 18 parts of guaiacol / maleic anhydride binary copolymer and 12 parts of 4,4-diaminodiphenylmethane in a specific ratio until homogeneous. Then add 2.5 parts of citric acid, 2 parts of polyetheramine D230, 6 parts of gas-generating agent, and the remainder is water in a specific ratio. Mix and stir until homogeneous. The total weight of the above components is 100 parts. Mix the two mixtures again until homogeneous to obtain a self-generating resin system for expanding pores and consolidating sand.

[0099] The system was injected into a sand column and aged at 50℃, 70℃, and 90℃. The permeability and compressive strength were observed. The results are shown in Table 8.

[0100] Table 8

[0101]

[0102]

[0103] Comparing Tables 2 with 4 and 5, it was found that the permeability retention rate of the sand column was significantly reduced when no gas-generating agent was used. While excessive use of the gas-generating agent had little impact on the permeability retention rate, the excessive gas significantly weakened the compressive strength. Comparing Tables 2 with 7, it was found that using triethylenetetramine as the curing agent resulted in a significant reduction in both permeability retention rate and compressive strength. Comparing Tables 2 with 8, it was found that the system did not cure at a low temperature of 50℃, and curing was incomplete at 70℃, resulting in weak compressive strength. All the tables above indicate that injecting different systems into sand columns and aging them at 90℃, while observing the permeability and compressive strength, showed that using 4,4-diaminodiphenylmethane as the curing agent yielded the best results. The optimal ratio was resin:curing agent:reinforcing agent:control agent:gas-generating agent:water = 18:12:2.5:2:6:59.5. This achieved a permeability retention rate of 90% and a compressive strength of 6.68 MPa. A higher permeability retention rate indicates less damage to the formation from sand fixation, while higher compressive strength indicates higher sand fixation intensity. Furthermore, it does not solidify at low temperatures, facilitating direct injection into the formation for sand fixation during surface construction. In summary, this invention successfully applies self-generating pore-expanding technology to a resin-based sand fixation system, achieving protection of reservoir permeability retention.

[0104] The present invention has been disclosed above with reference to preferred embodiments. However, those skilled in the art should understand that these embodiments are merely illustrative of the invention and should not be construed as limiting its scope. It should be noted that any variations and substitutions equivalent to these embodiments should be considered to be covered within the scope of the claims. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A self-generating resin system for expanding pores and fixing sand, characterized in that, Based on a total weight of 100 parts, it includes: 16-20 parts resin, 10-14 parts curing agent, 2-3 parts control agent, 1-3 parts reinforcing agent, 5-7 parts gas generating agent, and the balance water; The resin is a guaiacol / maleic anhydride copolymer, the curing agent is 4,4-diaminodiphenylmethane, the control agent is citric acid, and the reinforcing agent is polyetheramine D230. The gas-generating agent is prepared by the following method: (1) Microporous silica microspheres were added to a mixture of ethanol and water, KH-550 was added to the microporous silica microsphere suspension, and the mixture was ultrasonically treated to obtain a mixture; (2) The mixture is stirred, filtered and dried to obtain microporous silica microspheres-KH-550; (3) Add benzenesulfonyl hydrazine to the N,N-dimethylformamide solution, add the microporous silica microspheres-KH-550, and stir; (4) Discard the supernatant, collect the precipitate, wash it with methanol and filter it to obtain spherical solid particles of gas-generating agent; The weight ratio of the microporous silica microspheres, KH-550, and benzenesulfonyl hydrazine is (0.9-1):(1.9-2.1):(0.95-1.05). The resin, a guaiacol / maleic anhydride copolymer, is prepared by the following method: (1) Add 30g of guaiacol and 380ml of dichloroethane to a three-necked flask equipped with a mechanical stirrer and stir at room temperature until fully dissolved; then transfer the system to an ice-water bath and control the system temperature at 0℃. Slowly add 83.3g of anhydrous aluminum trichloride to the system and continue stirring for 20min; then slowly add 25g of maleic anhydride to the system and continue stirring at 0℃ for 30min. Then slowly raise the system temperature to 30℃ and react at this temperature for 8h; after the reaction is completed, pour the system into ice water and add 20ml of concentrated hydrochloric acid dropwise to the system; then collect the precipitate by vacuum filtration and recrystallize the crude product in distilled water. After drying, the first intermediate product in white crystalline form can be obtained. (2) Add 22.5 g of the first intermediate product and 150 ml of distilled water to a three-necked flask equipped with a mechanical stirrer and a reflux condenser; heat to reflux, and after the reactants are completely dissolved, add 15.6 g of hydrazine hydrate with a purity of 80% dropwise to the system, and continue to react under reflux for 2.5 h; after the reaction is completed, pour the mixture into a beaker, cool to room temperature, and then adjust the pH of the system to 7 with concentrated hydrochloric acid; filter, collect the product on the filter cake, wash it three times with distilled water, and dry it to obtain the pale yellow product, the second intermediate product; (3) In a three-necked flask equipped with a mechanical stirrer and a reflux condenser, add 11g of the second intermediate product, 14g of sodium m-nitrobenzenesulfonate, and 550ml of 0.5mol / L sodium hydroxide aqueous solution; heat to reflux and react for 10h; after the reaction is complete, pour the system into a beaker, cool to room temperature, and add concentrated hydrochloric acid dropwise until the pH of the system is 7; filter, collect the product on the filter cake, wash it three times with distilled water, and dry it to obtain the final yellow product guaiacol / maleic anhydride copolymer.

2. The self-generating resin system for expanding pores and fixing sand according to claim 1, characterized in that, The total weight is 100 parts, including: 18 parts resin, 12 parts curing agent, 2.5 parts control agent, 2 parts reinforcing agent, 6 parts gas generating agent, and the balance being water.

3. The method for preparing the self-generating pore-expanding and sand-fixing resin system according to any one of claims 1-2, characterized in that, include: First, mix the resin and curing agent in proportion and stir evenly. Then, add the control agent, reinforcing agent, gas generating agent and water in proportion and mix evenly to obtain a self-generating pore-expanding and sand-fixing resin system.

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