Solid delayed acid composition and preparation method thereof

Abstract

The invention relates to the technical field of acid fracturing of oil and gas wells, in particular to a solid delayed acid composition and a preparation method thereof, the solid delayed acid composition comprises a component A and a component B in a weight ratio of (1-4): 1; the component A comprises the following components in parts by weight: 2-9 parts of an organic solvent, 10-40 parts of solid acid, 0.1-2 parts of a complexing agent, 1-5 parts of a stabilizer, 4-12 parts of a corrosion inhibitor, 2-8 parts of a demulsifier and 40-80 parts of water, and the component B comprises the following components in parts by weight: 3-10 parts of a nonionic surfactant, 3-10 parts of an anionic surfactant, 2-10 parts of a thickening agent, 10-20 parts of a solvent and 40-70 parts of water. According to the solid delayed acid composition and the preparation method thereof, the solid delayed acid composition can be used for high-temperature deep carbonate rock acid fracturing construction, the problems of short effective distance and low effective hydrogen ion concentration of acid liquor are solved, and the purposes of high-temperature retarding and staged corrosion are achieved.

Description

Technical Field

[0001] This invention relates to the field of acid fracturing technology for oil and gas wells, and in particular to a solid delayed acid composition and its preparation method. Background Technology

[0002] With the development of the global oil and gas industry, oil and gas exploration and development have extended from shallow to deep and ultra-deep layers, and from medium and low temperatures to high temperatures. High-temperature deep carbonate rock acid fracturing places higher demands on the high-temperature slowing and dissolving capabilities of acid systems. Currently, the most commonly used acid fracturing system is the soil-acid system, which uses hydrochloric acid as a pre-fluid and hydrofluoric acid as the main treatment fluid. Solid acid fracturing systems are a gradually developing new type of fracturing system. Solid acids are powdered acids, which are easy to transport and store, solving the transportation safety issues of liquid acid fracturing systems.

[0003] Existing solid acid unblocking systems are essentially designed based on the principle of acid unblocking systems using hydrochloric acid as a pre-fluid and hydrofluoric acid as the main treatment fluid, such as hydrochloride salts and ammonium fluoride salts. These solid acids are still not suitable for use in deep reservoirs and far wells. For example, in the prior art, there is a Chinese invention patent document with publication number CN103224780A and publication date of July 31, 2013. The technical solution disclosed in this patent document is as follows: a slow-speed, low-damage acid system suitable for acidizing high-temperature condensate gas reservoirs. This acid system is suitable for acidizing high-temperature, deep wells, especially condensate gas reservoirs. Its components and weight parts are as follows: hydrofluoric acid 0.5~3 parts or fluoroboric acid 6~12 parts, organic ester 8~10 parts, catalyst 0.01~0.05 parts, corrosion inhibitor 0.1~1 parts, iron ion stabilizer 0.1~1 parts, clay stabilizer 0.1~1 parts, drainage aid 1~2 parts, and water 80~100 parts. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention proposes a solid delayed acid composition and its preparation method, which can be used for high-temperature deep carbonate rock acid fracturing construction, solving the problems of short effective distance of acid solution and low effective hydrogen ion concentration, and achieving the purpose of high-temperature slow-speed and staged dissolution.

[0005] This invention is achieved by adopting the following technical solution: A solid delayed acid composition comprising component A and component B in a weight ratio of (1-4):1; by weight, component A comprises 2-9 parts organic solvent, 10-40 parts solid acid, 0.1-2 parts complexing agent, 1-5 parts stabilizer, 4-12 parts corrosion inhibitor, 2-8 parts demulsifier, and 40-80 parts water; component B comprises 3-10 parts nonionic surfactant, 3-10 parts anionic surfactant, 2-10 parts thickener, 10-20 parts solvent, and 40-70 parts water.

[0006] The weight ratio of the thickener to the solvent is 3:(4.5~6); the weight ratio of the thickener, nonionic surfactant and anionic surfactant is (1.5~2.5):1:(1~1.8).

[0007] The weight ratio of the stabilizer, corrosion inhibitor and demulsifier is (3~5):(5~8):(1~4).

[0008] The solid acid includes aminosulfonic acid and citric acid, and the weight ratio of aminosulfonic acid to citric acid is 1:(0.2~0.5).

[0009] The complexing agent is at least one of ethylenediaminetetraacetic acid disodium salt, aminotrimethylene phosphonic acid, and hydroxyethylidene diphosphonic acid.

[0010] The stabilizer comprises glycidyltrimethylammonium chloride and hexadecyltrimethylammonium chloride, wherein the weight ratio of glycidyltrimethylammonium chloride to hexadecyltrimethylammonium chloride is 1:(2~3.5).

[0011] The demulsifier includes at least one of polysorbate 80, dehydrated sorbitol fatty acid ester, sorbitan monolaurate, OP 20, OP 10, lecithin, sodium caseinate, gum arabic, tamarind polysaccharide gum, and guar gum.

[0012] The nonionic surfactant includes at least one of fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, fatty acid diethanolamide, and polyethylene glycol.

[0013] The anionic surfactant includes at least one of sodium dodecylbenzenesulfonate, sodium fatty acid, sodium oleoylmethyl taurate, sodium dodecyl diphenyl ether disulfonate, petroleum sulfonate, and α-olefin sulfonate.

[0014] A method for preparing a solid delayed acid composition includes the following steps: S1. Prepare component A and component B separately: Add organic solvent, solid acid, complexing agent, stabilizer, corrosion inhibitor and demulsifier to water in sequence and mix well to obtain component A; add nonionic surfactant, anionic surfactant, thickener and solvent to water in sequence and mix well to obtain component B; S2. Mix the obtained components A and B evenly to obtain a solid delayed acid composition.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. In this invention, the synergistic relationship between component A and component B can solve the problems of short effective distance and low effective hydrogen ion concentration of acid solution; it can also solve the problem of poor high temperature resistance of thickener, which affects its slow release effect in the mid-to-long-range high temperature zone, and achieve the final goal of high-temperature slow-release and staged erosion.

[0016] 2. The thickener to solvent weight ratio is 3:(4.5~6), which can improve the acid solubility of solid delayed acid. The addition of a certain proportion of thickener can effectively increase the viscosity of the acid solution and effectively reduce the H+. + The diffusion rate towards the wall slows down the acid-rock reaction rate, while reducing acid loss to the formation and increasing the acid's action distance, giving the acid excellent slowing properties. Furthermore, by rationally configuring the thickener, nonionic surfactant, and anionic surfactant, the weight ratio of thickener, nonionic surfactant, and anionic surfactant is (1.5~2.5):1:(1~1.8). The thickener is an acrylamide polymer, and the hydrophobic groups in the surfactant, combined with the special water-soluble polymer formed on the long molecular chains of the acrylamide polymer with good water solubility, can undergo hydrophobic association in the system. This improves the high-temperature (150℃) slow-release effect of the solid delayed acid, solving the problem of poor high-temperature resistance of the thickener affecting its slow-release effect in the mid-to-high temperature zone.

[0017] 3. The solid acid comprises aminosulfonic acid and citric acid, wherein the weight ratio of aminosulfonic acid to citric acid is 1:(0.2~0.5). This allows for controlled etching, with minimal or no etching in the near-wellbore zone, while effectively etching and modifying the deep reservoir and the far end of the well. Furthermore, this solid acid formulation ensures that the prepared solid delayed acid composition performs better in high-temperature environments.

[0018] 4. In this invention, the weight ratio of stabilizer, corrosion inhibitor and demulsifier is also specified to better improve dispersion performance. Detailed Implementation

[0019] Example 1 This invention includes a solid delayed acid composition comprising component A and component B in a weight ratio of 3:1. By weight, component A comprises 5 parts organic solvent, 13.3 parts solid acid, 1 part complexing agent, 4 parts stabilizer, 7 parts corrosion inhibitor, 3 parts demulsifier, and 66.7 parts water; component B comprises 5 parts nonionic surfactant, 6 parts anionic surfactant, 9 parts thickener, 15 parts solvent, and 65 parts water. The weight ratio of the stabilizer, corrosion inhibitor, and demulsifier is preferred.

[0020] The solid acid includes at least one selected from aminosulfonic acid, chloroacetic acid, citric acid, chloroacetate, and oxalic acid. Preferably, the solid acid includes aminosulfonic acid and citric acid, and the weight ratio of aminosulfonic acid to citric acid is 1:(0.2~0.5). More preferably, and also used in this embodiment, the weight ratio of aminosulfonic acid to citric acid is 1:0.3.

[0021] The complexing agent includes at least one selected from disodium ethylenediaminetetraacetate, aminotrimethylenephosphonic acid, hydroxyethylidene diphosphonic acid, diethylenetriaminepentamethylenephosphonic acid, humic acid, or sodium gluconate. Preferably, the complexing agent includes at least one selected from disodium ethylenediaminetetraacetate, aminotrimethylenephosphonic acid, and hydroxyethylidene diphosphonic acid. More preferably, and also used in this embodiment, the complexing agent is disodium ethylenediaminetetraacetate.

[0022] The stabilizer comprises at least one selected from quaternary ammonium chloride, KCl saline, glycidyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, and choline chloride. Preferably, the stabilizer comprises glycidyltrimethylammonium chloride and hexadecyltrimethylammonium chloride, wherein the weight ratio of glycidyltrimethylammonium chloride to hexadecyltrimethylammonium chloride is 1:(2~3.5). More preferably, and also used in this embodiment, the weight ratio of glycidyltrimethylammonium chloride to hexadecyltrimethylammonium chloride is 1:2.8.

[0023] The corrosion inhibitor comprises at least one of aldehyde, ketone or amine condensates, imidazoline derivatives, pyridine, quinoline quaternary ammonium salts, and heteropolyamines. Preferably, the corrosion inhibitor comprises an imidazoline derivative. More preferably, and also used in this embodiment, the corrosion inhibitor is lauryl imidazoline betaine, purchased from Shandong Yingheshenglai Biotechnology Co., Ltd.

[0024] The demulsifier includes at least one of Tween-80 (polysorbate-80), Span 80 (sorbitol fatty acid ester), Span 20 (sorbitan monolaurate), OP-20 (CAS: 9002-93-1), OP-10 (dodecylphenol polyoxyethylene ether), lecithin, sodium caseinate, gum arabic, tamarind polysaccharide gum, and guar gum. Preferably, and also used in this embodiment, the demulsifier is OP-10 (dodecylphenol polyoxyethylene ether).

[0025] The nonionic surfactant includes at least one of fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, fatty acid diethanolamide, and polyethylene glycol. Preferably, the nonionic surfactant includes alkylphenol polyoxyethylene ether. More preferably, and also used in this embodiment, the nonionic surfactant is nonylphenol polyoxyethylene ether.

[0026] The anionic surfactant includes at least one of sodium dodecylbenzenesulfonate, sodium fatty acid, sodium oleoylmethyl taurate, sodium dodecyl diphenyl ether disulfonate, petroleum sulfonate, and α-olefin sulfonate. Preferably, and also used in this embodiment, the anionic surfactant is sodium fatty acid (CAS: 61790-25-8).

[0027] The organic solvent includes one of ethyl acetate and butyl acetate. Preferably, and also used in this embodiment, the organic solvent is ethyl acetate. Preferably, the solvent includes n-alkanes. More preferably, and also used in this embodiment, the solvent is n-dodecane.

[0028] The thickener includes at least one of acrylamide polymers and ethylene polymers. Preferably, the thickener includes an acrylamide polymer. More preferably, and also used in this embodiment, the thickener is an acrylamide-2-acrylamide-2-methylpropanesulfonic acid copolymer (CAS: 40623-75-4).

[0029] The method for preparing the above-mentioned solid delayed acid composition includes the following steps: S1. Prepare components A and B separately: Add the above-mentioned organic solvent, solid acid, complexing agent, stabilizer, corrosion inhibitor, and demulsifier to water sequentially, and stir at 500 rpm for 10 min until homogeneous to obtain component A. Add the nonionic surfactant, anionic surfactant, thickener, and solvent to water sequentially, and stir at 500 rpm for 10 min until homogeneous to obtain component B.

[0030] S2. Stir the obtained components A and B at 500 rpm for 10 min until they are mixed evenly to obtain a solid delayed acid composition.

[0031] Example 2 This invention includes a solid delayed acid composition comprising component A and component B in a weight ratio of 3:1. By weight, component A comprises 5 parts organic solvent, 20 parts solid acid, 1 part complexing agent, 4 parts stabilizer, 7 parts corrosion inhibitor, 3 parts demulsifier, and 60 parts water; component B comprises 5 parts nonionic surfactant, 6 parts anionic surfactant, 9 parts thickener, 15 parts solvent, and 65 parts water.

[0032] The solid acid is aminosulfonic acid and citric acid, with a weight ratio of 1:0.3. The complexing agent is disodium ethylenediaminetetraacetate. The stabilizer is glycidyltrimethylammonium chloride and hexadecyltrimethylammonium chloride, with a weight ratio of 1:2.8. The corrosion inhibitor is laurylimidazoline betaine, purchased from Shandong Yingheshenglai Biotechnology Co., Ltd. The demulsifier is OP-10 (dodecylphenol polyoxyethylene ether). The nonionic surfactant is nonylphenol polyoxyethylene ether. The anionic surfactant is sodium fatty acid (CAS: 61790-25-8). The organic solvent is ethyl acetate, and the solvent is n-dodecane. The thickener is acrylamide-2-acrylamide-2-methylpropanesulfonic acid copolymer (CAS: 40623-75-4).

[0033] The preparation method of the above-mentioned solid delayed acid composition is the same as that in Example 1, and will not be repeated in this example.

[0034] Example 3 This invention includes a solid delayed acid composition comprising component A and component B in a weight ratio of 3:1. By weight, component A comprises 5 parts organic solvent, 26.7 parts solid acid, 1 part complexing agent, 4 parts stabilizer, 7 parts corrosion inhibitor, 3 parts demulsifier, and 53.3 parts water; component B comprises 5 parts nonionic surfactant, 6 parts anionic surfactant, 9 parts thickener, 15 parts solvent, and 65 parts water.

[0035] The solid acid is aminosulfonic acid and citric acid, with a weight ratio of 1:0.3. The complexing agent is disodium ethylenediaminetetraacetate. The stabilizer is glycidyltrimethylammonium chloride and hexadecyltrimethylammonium chloride, with a weight ratio of 1:2.8. The corrosion inhibitor is laurylimidazoline betaine, purchased from Shandong Yingheshenglai Biotechnology Co., Ltd. The demulsifier is OP-10 (dodecylphenol polyoxyethylene ether). The nonionic surfactant is nonylphenol polyoxyethylene ether. The anionic surfactant is sodium fatty acid (CAS: 61790-25-8). The organic solvent is ethyl acetate, and the solvent is n-dodecane. The thickener is acrylamide-2-acrylamide-2-methylpropanesulfonic acid copolymer (CAS: 40623-75-4).

[0036] The preparation method of the above-mentioned solid delayed acid composition is the same as that in Example 1, and will not be repeated in this example.

[0037] Example 4 This invention includes a solid delayed acid composition comprising component A and component B in a weight ratio of 3:1. By weight, component A comprises 5 parts organic solvent, 33.3 parts solid acid, 1 part complexing agent, 4 parts stabilizer, 7 parts corrosion inhibitor, 3 parts demulsifier, and 46.7 parts water; component B comprises 5 parts nonionic surfactant, 6 parts anionic surfactant, 9 parts thickener, 15 parts solvent, and 65 parts water.

[0038] The solid acid is aminosulfonic acid and citric acid, with a weight ratio of 1:0.3. The complexing agent is disodium ethylenediaminetetraacetate. The stabilizer is glycidyltrimethylammonium chloride and hexadecyltrimethylammonium chloride, with a weight ratio of 1:2.8. The corrosion inhibitor is laurylimidazoline betaine, purchased from Shandong Yingheshenglai Biotechnology Co., Ltd. The demulsifier is OP-10 (dodecylphenol polyoxyethylene ether). The nonionic surfactant is nonylphenol polyoxyethylene ether. The anionic surfactant is sodium fatty acid (CAS: 61790-25-8). The organic solvent is ethyl acetate, and the solvent is n-dodecane. The thickener is acrylamide-2-acrylamide-2-methylpropanesulfonic acid copolymer (CAS: 40623-75-4).

[0039] The preparation method of the above-mentioned solid delayed acid composition is the same as that in Example 1, and will not be repeated in this example.

[0040] Example 5 This invention includes a solid delayed acid composition comprising component A and component B in a weight ratio of 3:1. By weight, component A comprises 5 parts organic solvent, 40 parts solid acid, 1 part complexing agent, 4 parts stabilizer, 7 parts corrosion inhibitor, 3 parts demulsifier, and 40 parts water; component B comprises 5 parts nonionic surfactant, 6 parts anionic surfactant, 9 parts thickener, 15 parts solvent, and 65 parts water.

[0041] The solid acid is aminosulfonic acid and citric acid, with a weight ratio of 1:0.3. The complexing agent is disodium ethylenediaminetetraacetate. The stabilizer is glycidyltrimethylammonium chloride and hexadecyltrimethylammonium chloride, with a weight ratio of 1:2.8. The corrosion inhibitor is laurylimidazoline betaine, purchased from Shandong Yingheshenglai Biotechnology Co., Ltd. The demulsifier is OP-10 (dodecylphenol polyoxyethylene ether). The nonionic surfactant is nonylphenol polyoxyethylene ether. The anionic surfactant is sodium fatty acid (CAS: 61790-25-8). The organic solvent is ethyl acetate, and the solvent is n-dodecane. The thickener is acrylamide-2-acrylamide-2-methylpropanesulfonic acid copolymer (CAS: 40623-75-4).

[0042] The preparation method of the above-mentioned solid delayed acid composition is the same as that in Example 1, and will not be repeated in this example.

[0043] Example 6 This invention includes a solid delayed acid composition comprising component A and component B in a weight ratio of 1:1. By weight, component A comprises 2 parts organic solvent, 10 parts solid acid, 0.1 parts complexing agent, 1 part stabilizer, 4 parts corrosion inhibitor, 2 parts demulsifier, and 80.1 parts water; component B comprises 3 parts nonionic surfactant, 3 parts anionic surfactant, 2 parts thickener, 10 parts solvent, and 82 parts water.

[0044] The solid acid is aminosulfonic acid and citric acid, with a weight ratio of 1:0.2. The complexing agent is disodium ethylenediaminetetraacetate. The stabilizer is glycidyltrimethylammonium chloride and hexadecyltrimethylammonium chloride, with a weight ratio of 1:2. The corrosion inhibitor is lauryl imidazoline betaine, purchased from Shandong Yingheshenglai Biotechnology Co., Ltd. The demulsifier is OP-10 (dodecylphenol polyoxyethylene ether). The nonionic surfactant is nonylphenol polyoxyethylene ether. The anionic surfactant is sodium fatty acid (CAS: 61790-25-8). The organic solvent is ethyl acetate, and the solvent is n-dodecane. The thickener is acrylamide-2-acrylamide-2-methylpropanesulfonic acid copolymer (CAS: 40623-75-4).

[0045] The preparation method of the above-mentioned solid delayed acid composition is the same as that in Example 1, and will not be repeated in this example.

[0046] Example 7 This invention includes a solid delayed acid composition comprising component A and component B in a weight ratio of 4:1. By weight, component A comprises 9 parts organic solvent, 40 parts solid acid, 2 parts complexing agent, 5 parts stabilizer, 12 parts corrosion inhibitor, 8 parts demulsifier, and 24 parts water; component B comprises 10 parts nonionic surfactant, 10 parts anionic surfactant, 10 parts thickener, 20 parts solvent, and 50 parts water.

[0047] The solid acid is aminosulfonic acid and citric acid, with a weight ratio of 1:0.5. The complexing agent is disodium ethylenediaminetetraacetate. The stabilizer is glycidyltrimethylammonium chloride and hexadecyltrimethylammonium chloride, with a weight ratio of 1:3.5. The corrosion inhibitor is lauryl imidazoline betaine, purchased from Shandong Yingheshenglai Biotechnology Co., Ltd. The demulsifier is OP-10 (dodecylphenol polyoxyethylene ether). The nonionic surfactant is nonylphenol polyoxyethylene ether. The anionic surfactant is sodium fatty acid (CAS: 61790-25-8). The organic solvent is ethyl acetate, and the solvent is n-dodecane. The thickener is acrylamide-2-acrylamide-2-methylpropanesulfonic acid copolymer (CAS: 40623-75-4).

[0048] The preparation method of the above-mentioned solid delayed acid composition is the same as that in Example 1, and will not be repeated in this example.

[0049] Comparative Example 1 A comparative delayed acid composition was prepared, comprising component A and component B in a weight ratio of 3:1. By weight, component A comprises 5 parts organic solvent, 20 parts solid acid, 1 part complexing agent, 4 parts stabilizer, 7 parts corrosion inhibitor, 3 parts demulsifier, and 60 parts water; component B comprises 5 parts nonionic surfactant, 6 parts anionic surfactant, 9 parts thickener, 15 parts solvent, and 65 parts water. The solid acid is hydrochloric acid, and the remaining compounds are selected as in Example 2.

[0050] Comparative Example 2 A comparative delayed acid composition was prepared, comprising component A and component B in a weight ratio of 3:1. By weight, component A comprised 5 parts organic solvent, 13.3 parts solid acid, 1 part complexing agent, 4 parts stabilizer, 7 parts corrosion inhibitor, 3 parts demulsifier, and 66.7 parts water; component B comprised 8 parts nonionic surfactant, 6 parts anionic surfactant, 6 parts thickener, 15 parts solvent, and 65 parts water. The compounds were selected as in Example 1.

[0051] The delayed acid compositions prepared in Examples 1-5 and Comparative Examples 1-2 were subjected to performance tests, including corrosion performance tests and effective acid concentration tests. The test data are shown in Table 1 below.

[0052] Specifically, the corrosion performance refers to the corrosion performance of the delayed acid compositions in Examples 1-5 and Comparative Examples 1-2 tested according to SY / T 5886-2018 "Evaluation Method for Performance of Acidifying Working Fluids". The specific operation is as follows: (1) Grind the rock blocks with a grinding wheel or coarse sandpaper until the surface is flat and the surface area of ​​each rock block is similar. Place them in a drying oven to dry for later use. (2) The delayed acid compositions prepared in Examples 1-5 and Comparative Examples 1-2 were placed in different reaction vessels at a ratio of 10 mL: 1 g to rock fragments. After heating at 90°C for 20 min, the remaining rock fragments were filtered out using a 200-mesh filter. The remaining liquid was then subjected to harmless treatment. The filtered rock fragments were washed with tap water and dried in a 70°C constant temperature oven for 1 h. The mass m2 was weighed, and the acid solubility was calculated as follows: η = ((1-m2) / 1) * 100%.

[0053] The effective acid concentration specifically refers to the effective acid concentration measured at 25℃, 50℃, 90℃, and 150℃ for 60 minutes. "-" indicates that no test was performed.

[0054] Table 1 As can be seen from Table 1 above, the effective acid concentration increases with increasing temperature. The delayed acid composition in this invention can control the near-wellbore zone to be un-etched or weakly etched, while etching and modifying the deep reservoir and far wellbore (increasing the effective acid concentration).

[0055] Referring to the standard "Technical Conditions for Water Resistance Reduction in Shale Gas Fracturing", component B in Example 1 was tested, and the test data are listed in Table 2 below: Table 2 As can be seen from Table 2 above, component B alone can achieve ultra-high temperature resistance. Therefore, it can be determined that the specific ratio of thickener, nonionic surfactant and anionic surfactant can improve the sustained-release effect of solid delayed acid at high temperature (150℃).

[0056] In summary, any other corresponding modifications made by those skilled in the art after reading this invention document, without requiring creative mental effort, based on the technical solutions and concepts of this invention, are all within the scope of protection of this invention.

Claims

1. A solid delayed acid composition, characterized in that: It includes component A and component B in a weight ratio of (1~4):1; by weight, component A includes 2~9 parts organic solvent, 10~40 parts solid acid, 0.1~2 parts complexing agent, 1~5 parts stabilizer, 4~12 parts corrosion inhibitor, 2~8 parts demulsifier and 40~80 parts water, and component B includes 3~10 parts nonionic surfactant, 3~10 parts anionic surfactant, 2~10 parts thickener, 10~20 parts solvent and 40~70 parts water.

2. The solid delayed acid composition according to claim 1, characterized in that: The weight ratio of the thickener to the solvent is 3:(4.5~6); the weight ratio of the thickener, nonionic surfactant and anionic surfactant is (1.5~2.5):1:(1~1.8).

3. The solid delayed acid composition according to claim 2, characterized in that: The weight ratio of the stabilizer, corrosion inhibitor and demulsifier is (3~5):(5~8):(1~4).

4. The solid delayed acid composition according to claim 3, characterized in that: The solid acid includes aminosulfonic acid and citric acid, and the weight ratio of aminosulfonic acid to citric acid is 1:(0.2~0.5).

5. The solid delayed acid composition according to claim 3, characterized in that: The complexing agent is at least one of ethylenediaminetetraacetic acid disodium salt, aminotrimethylene phosphonic acid, and hydroxyethylidene diphosphonic acid.

6. The solid delayed acid composition according to claim 3, characterized in that: The stabilizer comprises glycidyltrimethylammonium chloride and hexadecyltrimethylammonium chloride, wherein the weight ratio of glycidyltrimethylammonium chloride to hexadecyltrimethylammonium chloride is 1:(2~3.5).

7. The solid delayed acid composition according to claim 3, characterized in that: The demulsifier includes at least one of polysorbate 80, dehydrated sorbitol fatty acid ester, sorbitan monolaurate, OP 20, OP 10, lecithin, sodium caseinate, gum arabic, tamarind polysaccharide gum, and guar gum.

8. The solid delayed acid composition according to claim 3, characterized in that: The nonionic surfactant includes at least one of fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, fatty acid diethanolamide, and polyethylene glycol.

9. A solid delayed acid composition according to claim 3, characterized in that: The anionic surfactant includes at least one of sodium dodecylbenzenesulfonate, sodium fatty acid, sodium oleoylmethyl taurate, sodium dodecyl diphenyl ether disulfonate, petroleum sulfonate, and α-olefin sulfonate.

10. A method for preparing a solid delayed acid composition according to any one of claims 1 to 9, characterized in that: Includes the following steps: S1. Prepare component A and component B separately: Add organic solvent, solid acid, complexing agent, stabilizer, corrosion inhibitor and demulsifier to water in sequence and mix well to obtain component A; add nonionic surfactant, anionic surfactant, thickener and solvent to water in sequence and mix well to obtain component B; S2. Mix the obtained components A and B evenly to obtain a solid delayed acid composition.

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