Gas well foam scrubbing agent and preparation and application thereof

Abstract

The invention discloses a gas well foam scrubbing agent as well as preparation and application thereof, and relates to the technical field of gas well foam scrubbing agents, the gas well foam scrubbing agent comprises 10%-20% of sodium alpha-olefin sulfonate, 5%-10% of lauramide propyl amine oxide, 0.3%-0.6% of hydroxypropyl guar gum, 5%-10% of block polyether, 3%-6% of ethoxylated sulfonate, 0.5%-2% of hydrophobic nano silicon dioxide, 3%-8% of a microencapsulation foaming agent, 1%-3% of citric acid, 0.5%-1% of benzotriazole and the balance of deionized water; by compounding foaming, foam stabilizing and anti-interference functional components and introducing a microencapsulated foaming agent and hydrophobic nano silicon dioxide, the adaptability and efficiency of the foam scrubbing agent under complex working conditions are remarkably improved, active ingredients can be controllably released by utilizing a temperature-sensitive microcapsule in a high-temperature environment, and the foam scrubbing agent has a good foam scrubbing effect. Block polyether and nano silicon dioxide are combined to form a stable barrier on a gas-liquid interface, so that the damage of condensate oil is effectively resisted, and meanwhile, ethoxylated sulfonate and citric acid cooperate to maintain the stability of the surfactant under high salinity.

Description

Technical Field

[0001] The invention relates to the technical field of gas well foaming agents, in particular to a gas well foaming agent and the preparation and application thereof. Background Art

[0002] Gas well foaming agent technology is a chemical production-increasing technology used to improve the drainage and gas production efficiency of gas wells. Its core is to inject chemicals with strong foaming and stabilizing capabilities into the wellbore, and use the natural gas flow to carry the bottom well liquid to the ground, thereby removing the liquid and restoring or improving the gas well production capacity.

[0003] In the field of gas well foaming agents, the surfactants in traditional foaming agents are easily degraded or released rapidly at the high-temperature bottom of the well, resulting in a short foam life and reduced drainage efficiency. In addition, in a high-salt environment, calcium, magnesium and other ions easily form precipitation with anionic surfactants, reducing the foaming ability. At the same time, in gas wells with high condensate oil content, the oil phase will penetrate and destroy the foam liquid film, causing the foam to collapse rapidly. Summary of the Invention

[0004] In view of the above existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides a gas well foaming agent and its preparation and application to solve the problem that the surfactants in traditional foaming agents are easily degraded or rapidly released at the high-temperature bottom of the well, resulting in a short foam life and reduced drainage efficiency. In addition, in a high-salt environment, calcium, magnesium and other ions are easily precipitated with anionic surfactants, reducing the foaming ability. At the same time, in gas wells with high condensate oil content, the oil phase will penetrate and destroy the foam liquid film, causing the foam to collapse rapidly.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: In a first aspect, the present invention provides a gas well foaming agent, comprising: Sodium α-olefin sulfonate 10%~20%, lauramide propyl amine oxide 5%~10%, hydroxypropyl guar gum 0.3%~0.6%, block polyether 5%~10%, ethoxylated sulfonate 3%~6%, hydrophobic nano-silica 0.5%~2%, microencapsulated foaming agent 3%~8%, citric acid 1%~3%, benzotriazole 0.5%~1%, and the balance deionized water.

[0007] As a preferred embodiment of the gas well foaming agent of the present invention, the core material of the microencapsulated foaming agent is an aqueous solution of sodium α-olefin sulfonate containing a temperature-sensitive monomer, and the wall material is a gelatin-gum arabic composite.

[0008] As a preferred embodiment of the gas well foaming agent of the present invention, the weight proportion of tetradecane sulfonate in the sodium α-olefin sulfonate is not less than 60%, and the block polyether is a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer.

[0009] As a preferred embodiment of the gas well foaming agent of the present invention, the temperature-sensitive monomer is N-isopropylacrylamide.

[0010] In a second aspect, the present invention provides a method for preparing a gas well foaming agent, which comprises: S1. Prepare foaming module solution, foam stabilizing module solution and anti-interference module solution respectively; S2, mixing hydrophobic nano-silica with isopropyl alcohol, and subjecting the mixture to ultrasonic dispersion treatment to obtain the nano-silica pre-dispersed slurry; S3, preparing a microencapsulated foaming agent; S4, compounding and mixing the foaming module solution, the foam stabilizing module solution, the anti-interference module solution, the nano-silica pre-dispersed slurry and the microencapsulated foaming agent; S5. Ripening the compounded mixture to obtain the gas well foaming agent.

[0011] As a preferred embodiment of the method for preparing the gas well foaming agent of the present invention, the steps of preparing the foaming module solution, the foam stabilizing module solution and the anti-interference module solution are as follows: Add deionized water to the reactor, heat to 45 to 55 degrees Celsius, add sodium α-olefin sulfonate under stirring until it is completely dissolved to obtain a foaming module solution; Deionized water was added to the second reactor, and hydroxypropyl guar gum was added at a shear rate of 2,000 rpm. The shearing was continued for 30 minutes, and the shear rate was reduced to 500 rpm. Lauramide propylamine oxide was added and stirred for 60 minutes to obtain a foam stabilizing module solution. Add the block polyether and ethoxylated sulfonate into the third reactor, heat to 55 to 65 degrees Celsius and stir until melted and mixed; add citric acid and benzotriazole, stir and dissolve to obtain an anti-interference module solution.

[0012] As a preferred embodiment of the method for preparing the gas well foaming agent of the present invention, the specific steps of preparing the microencapsulated foaming agent are as follows: Take part of the foaming module solution and add the temperature-sensitive monomer to dissolve to form the core material; The core material is added to an aqueous solution of gelatin and gum arabic at 45 degrees Celsius and a pH value of 4.5, and coated to form microcapsules through a complex coacervation reaction; After gelation, cross-linking and solidification, filtration, washing and drying, a powdery microencapsulated foaming agent is obtained.

[0013] As a preferred embodiment of the method for preparing the gas well foaming agent of the present invention, the specific steps of compounding and mixing are: The remaining foaming module solution was transferred to the finished product reactor, and the foam stabilizing module solution and the anti-interference module solution were added in sequence under stirring and mixed evenly; adding the nano-silica pre-dispersed slurry under shearing; The microencapsulated foaming agent was added with stirring.

[0014] In a third aspect, the present invention provides an application of a gas well foaming agent, which is used for drainage and gas production operations in gas wells with a high condensate oil content, wherein the hydrophobic nano-silica and the block polyether act synergistically to form a stable barrier at the gas-liquid interface, thereby inhibiting the destruction of the foam film by the condensate oil.

[0015] Fourthly, an application of a gas well foaming agent is provided, which is used for drainage and gas production operations in high-temperature and high-mineralization gas wells, wherein the microencapsulated foaming agent is triggered to release under a high-temperature environment at the bottom of the well, and the ethoxylated sulfonate and citric acid act synergistically to maintain the activity of the surfactant in a high-mineralization environment.

[0016] The beneficial effects of the present invention are as follows: by compounding foaming, foam stabilizing and anti-interference functional components, and introducing microencapsulated foaming agents and hydrophobic nano-silica, the adaptability and efficiency of the foaming agent under complex working conditions are significantly improved; the temperature-sensitive microcapsules are used to controllably release active ingredients under high temperature environments; the block polyether and nano-silica are combined to form a stable barrier at the gas-liquid interface, effectively resisting condensate oil damage; at the same time, ethoxylated sulfonates and citric acid synergistically maintain the stability of the surfactant under high salinity, thereby achieving efficient and continuous drainage and gas recovery under harsh conditions such as high temperature, high salinity and high condensate oil content, extending the foaming cycle and improving the gas well productivity. DETAILED DESCRIPTION

[0017] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the specification.

[0018] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0019] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0020] Example 1 is the first embodiment of the present invention, which provides a gas well foaming agent, including: Sodium α-olefin sulfonate 10%-20%, lauramidopropylamine oxide 5%-10%, hydroxypropyl guar gum 0.3%-0.6%, block polyether 5%-10%, ethoxylated sulfonate 3%-6%, hydrophobic nano-silica 0.5%-2%, microencapsulated foaming agent 3%-8%, citric acid 1%-3%, benzotriazole 0.5%-1%, and the balance deionized water; Furthermore, the core material of the microencapsulated foaming agent is an aqueous solution of sodium α-olefin sulfonate containing a temperature-sensitive monomer, and the wall material is a gelatin-gum arabic composite; The weight proportion of tetradecane sulfonate in the sodium α-olefin sulfonate is not less than 60%, and the block polyether is a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer; The temperature-sensitive monomer is N-isopropylacrylamide; It should be noted that the gas well foaming agent achieves slow-release and controllable release of foaming performance by introducing microencapsulated foaming agents. Especially in high-temperature deep well environments, the temperature-sensitive monomer N-isopropylacrylamide can undergo a phase change at a specific temperature threshold, triggering the microcapsule to rupture and release the core material, thereby improving the adaptability and sustainability of the foaming agent under different well depth conditions. At the same time, the hydrophobic nano-silica works synergistically with block polyether and ethoxylated sulfonate to significantly enhance the foam stability and inhibit the damage of polyvalent metal ions in formation water to the foaming system, thereby improving the anti-interference ability.

[0021] Example 2 is the second embodiment of the present invention, which provides a method for preparing a gas well foaming agent, comprising: S1. Prepare foaming module solution, foam stabilizing module solution and anti-interference module solution respectively; Furthermore, deionized water is added to the reactor, heated to 45 to 55 degrees Celsius, and sodium α-olefin sulfonate is added under stirring until completely dissolved to obtain a foaming module solution; Deionized water was added to the second reactor, and hydroxypropyl guar gum was added at a shear rate of 2,000 rpm. The shearing was continued for 30 minutes, and the shear rate was reduced to 500 rpm. Lauramide propylamine oxide was added and stirred for 60 minutes to obtain a foam stabilizing module solution. Add the block polyether and ethoxylated sulfonate to the third reactor, heat to 55 to 65 degrees Celsius and stir until melted and mixed; add citric acid and benzotriazole, stir and dissolve to obtain an anti-interference module solution; It should be noted that the modular preparation process effectively avoids the mutual interference that may occur among the functional components during the mixing process, especially the compatibility problem of the polymer thickener hydroxypropyl guar gum with surfactants under low shear. The gradient shear control ensures its full swelling and uniform dispersion, thereby ensuring the rheological properties of the foam stabilizing module. At the same time, the step-by-step heating and dissolution strategy is conducive to the stable introduction of heat-sensitive components, improving the repeatability of the overall formula and the feasibility of industrial production.

[0022] S2, mixing hydrophobic nano-silica with isopropyl alcohol, and subjecting the mixture to ultrasonic dispersion treatment to obtain the nano-silica pre-dispersed slurry; Furthermore, the weight ratio of the hydrophobic nano-silica to isopropyl alcohol is 1:1 to 1:2; Ultrasonic dispersion treatment uses a probe-type ultrasonic cell disruptor with a power control range of 500W to 800W and an ultrasonic treatment time of 10 to 20 minutes. An intermittent mode is used during the process to prevent overheating of the system, which may cause solvent volatilization or changes in the surface properties of the nanoparticles. The ultrasonic treatment was carried out under water bath cooling conditions, and the container containing the mixture was placed in an ice water bath to ensure that the temperature during the dispersion process was maintained below 25 degrees Celsius; It should be noted that the use of isopropyl alcohol as the dispersing medium for hydrophobic nano-silica can effectively reduce its tendency to agglomerate. Combined with the high-intensity intermittent treatment of the ultrasonic cell disruptor, efficient disaggregation and stable suspension of the nanoparticles can be achieved under ice-water bath cooling conditions, preventing degradation of the surface hydrophobic properties due to local overheating, ensuring that it can be evenly distributed in the subsequent compounding process and play an interface regulation role, thereby enhancing the mechanical strength and anti-collapse ability of the foam film.

[0023] S3, preparing a microencapsulated foaming agent; Furthermore, a portion of the foaming module solution is added to the temperature-sensitive monomer to dissolve and form the core material; The core material is added to an aqueous solution of gelatin and gum arabic at 45 degrees Celsius and a pH value of 4.5, and coated to form microcapsules through a complex coacervation reaction; After gelation, cross-linking and curing, filtering, washing and drying, a powdered microencapsulated foaming agent is obtained; It should be noted that the microencapsulation process adopts the gelatin-gum arabic complex coacervation method, which utilizes the electrostatic interaction between the two near the isoelectric point to form a dense capsule wall. Combined with the temperature-sensitive properties of N-isopropylacrylamide, the microcapsules remain stably closed at room temperature. In the high-temperature environment underground (above 32°C), a volume phase change occurs, causing the capsule wall to rupture and release the core material sodium α-olefin sulfonate, realizing temperature-responsive intelligent release and significantly extending the effective action period of the foaming agent.

[0024] S4, compounding and mixing the foaming module solution, the foam stabilizing module solution, the anti-interference module solution, the nano-silica pre-dispersed slurry and the microencapsulated foaming agent; Furthermore, the remaining foaming module solution is transferred to the finished product reactor, and the foam stabilizing module solution and the anti-interference module solution are added in sequence under stirring and mixed evenly; adding the nano-silica pre-dispersed slurry under shearing; adding the microencapsulated foaming agent under stirring; It should be noted that the order of mixing the liquid modules first and then adding the solid or slurry components in sequence during the compounding process can effectively avoid the premature rupture of the microencapsulated foaming agent under high shear conditions and ensure its structural integrity. At the same time, the addition of nano-silica pre-dispersed slurry under shear conditions helps it to be evenly distributed in the system. The final composite foaming agent has the characteristics of rapid foaming, long-lasting foam stability and strong anti-pollution ability, and is suitable for continuous or intermittent drainage and gas production operations in gas wells under complex working conditions.

[0025] S5, aging the compounded mixture to obtain the gas well foaming agent; Furthermore, the aging process is to store the compounded mixture in a sealed container at room temperature for 20 to 28 hours; During the aging process, the system does not require any mechanical stirring; It should be noted that this aging step allows the components in the system to complete the transition from mechanical mixing to thermodynamic stability by providing a controlled, undisturbed standing time, ensuring that the nano-synergist, polymer and surfactant molecules can form a stable and synergistic composite interface structure, thereby achieving optimal product performance and excellent storage stability.

[0026] Example 3: The gas well foaming agent and preparation method provided in this example are roughly the same as those in Example 1 and Example 2, with the main differences being: A gas well foaming agent is composed of the following components in weight percentage: 15% sodium α-olefin sulfonate, 8% lauramide propylamine oxide, 0.5% hydroxypropyl guar gum, 8% block polyether, 5% ethoxylated sulfonate, 1.5% hydrophobic nano-silica, 6% microencapsulated foaming agent, 2% citric acid, 0.8% benzotriazole, and the balance deionized water.

[0027] The preparation method of the microencapsulated foaming agent comprises the following steps: I. Take 30% of the foaming module solution described in Example 2, add 4% by mass of N-isopropylacrylamide to the solution, stir and dissolve, to form a core material solution; Ⅱ. Dissolve gelatin and gum arabic in deionized water at a mass ratio of 1:1.2 to prepare a wall material solution with a total concentration of 8%. Adjust the system temperature to 45°C and the pH to 4.5. III. Slowly add the core material solution obtained in step I to the wall material solution in step II under stirring conditions to carry out complex coacervation coating reaction, and continue stirring for 2 hours; IV. Cool the system to 10°C, add 3% by mass glutaraldehyde aqueous solution as a crosslinking agent, and continue stirring and curing for 3 hours; V. The obtained microcapsule slurry was filtered, washed three times with deionized water, and then dried in a vacuum drying oven at 40° C. for 12 hours to obtain a powdered microencapsulated foaming agent product.

[0028] The block polyether is a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer (EO / PO ratio is 3:2) with a molecular weight in the range of 4000 to 6000.

[0029] The weight proportion of carbon tetradecene (C14) paraffin sulfonate in sodium α-olefin sulfonate is 65%.

[0030] The average particle size of hydrophobic nano-silica is 20nm and the specific surface area is 200-300 m² / g.

[0031] In the preparation of the nano-silica pre-dispersed slurry, the weight ratio of hydrophobic nano-silica to isopropyl alcohol was 1:1.5. Ultrasonic dispersion was performed using 600 W power and intermittent mode (working for 5 seconds and pausing for 3 seconds) for a total of 15 minutes, and the temperature was controlled in an ice water bath throughout the process.

[0032] The aging process is to place the compounded mixture in a sealed container at room temperature (25°C) for 24 hours without any stirring operation.

[0033] Comparative Example 1 The gas well foaming agent and preparation method provided in this embodiment are substantially the same as those in Example 3, with the main difference being that the raw materials do not contain a microencapsulated foaming agent and are replaced with an equal amount of ordinary sodium α-olefin sulfonate (i.e., the total sodium α-olefin sulfonate content is 21%); Comparative Example 2 The gas well foaming agent and preparation method provided in this embodiment are substantially the same as those in Example 3, with the main difference being that the raw material does not contain hydrophobic nano-silica and is replaced by an equal amount of deionized water; Comparative Example 3 The gas well foaming agent and preparation method provided in this embodiment are substantially the same as those in Example 3, with the main difference being that a mixed solution of N-isopropylacrylamide and sodium α-olefin sulfonate without microencapsulation is directly added to the system, while the other components and processes remain unchanged. Comparative Example 4 The gas well foaming agent and preparation method provided in this embodiment are substantially the same as those in Example 3, with the main difference being that an equal amount of sodium dodecylbenzenesulfonate is used instead of ethoxylated sulfonate; Performance Testing Equal amounts of the gas well foaming agents prepared in Example 3 and Comparative Examples 1 to 4 were taken and tested for foaming performance, foam half-life, anti-salinity and anti-condensate oil capacity under simulated wellbore conditions. The obtained data are recorded in the following table: Test items Foaming volume / mL Foam half-life / min <![CDATA[Anti-mineralization ability (10×10 4 mg / LCa²⁺+Mg²⁺)]]> Condensate resistance (15% oil phase) High temperature response release rate (80℃, 2h) / % Foam height retention rate / % Foam height retention rate / % Example 3 480 96 88 85 79.5 Comparative Example 1 510 52 75 72 98.2 Comparative Example 2 460 65 80 68 78.3 Comparative Example 3 495 58 73 70 96.8 Comparative Example 4 430 70 62 75 77.6 By analyzing the relevant data in the above-mentioned tables, it can be known that the gas well foaming agent prepared by Example 3 of the present invention shows excellent performance in foaming ability, foam stability, resistance to high salinity and anti-condensate oil, especially possesses controlled release characteristics under high temperature conditions, significantly extending the foam action cycle; and Comparative Example 1 lacks a microcapsule structure, although the initial foaming amount is high but the foam decays quickly, and high temperature release is too fast to cause poor persistence; Comparative Example 2 lacks nano-silica interface reinforcement, and oil resistance is significantly reduced; Comparative Example 3 is not coated with a temperature-sensitive monomer, and is rapidly released at high temperature, and a sustained-release effect cannot be achieved; Comparative Example 4 uses poor salt resistance of traditional sulfonates, resulting in a significant attenuation of performance under high salinity. Thus it is shown that the present invention, through microencapsulation design, nano-enhancement and anti-interference component collaboration, constructs a kind of efficient and long-lasting foaming system that adapts to complex gas well environments, with good field application prospects and promotion value.

[0034] In summary, the present invention significantly improves the adaptability and efficiency of the foaming agent under complex working conditions by compounding foaming, foam stabilizing and anti-interference functional components and introducing microencapsulated foaming agent and hydrophobic nano-silica. It utilizes temperature-sensitive microcapsules to controllably release active ingredients under high temperature environment, combines block polyether and nano-silica to form a stable barrier at the gas-liquid interface, and effectively resists condensate oil damage. At the same time, ethoxylated sulfonate and citric acid synergistically maintain the stability of the surfactant under high salinity, thereby achieving efficient and continuous drainage and gas recovery under harsh conditions such as high temperature, high salinity and high condensate oil content, extending the foaming cycle and improving gas well productivity.

[0035] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A gas well foaming agent, characterized in that: include: Sodium α-olefin sulfonate 10%~20%, lauramide propyl amine oxide 5%~10%, hydroxypropyl guar gum 0.3%~0.6%, block polyether 5%~10%, ethoxylated sulfonate 3%~6%, hydrophobic nano-silica 0.5%~2%, microencapsulated foaming agent 3%~8%, citric acid 1%~3%, benzotriazole 0.5%~1%, and the balance deionized water.

2. The gas well foaming agent according to claim 1, wherein: The core material of the microencapsulated foaming agent is an aqueous solution of sodium α-olefin sulfonate containing a temperature-sensitive monomer, and the wall material is a gelatin-arabic gum complex.

3. The gas well foaming agent according to claim 2, wherein: The weight proportion of tetradecane sulfonate in the sodium α-olefin sulfonate is not less than 60%, and the block polyether is a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer.

4. The gas well foaming agent according to claim 3, wherein: The temperature-sensitive monomer is N-isopropylacrylamide.

5. A method for preparing a gas well foaming agent, the gas well foaming agent according to claims 1-4, characterized in that: include: S1. Prepare foaming module solution, foam stabilizing module solution and anti-interference module solution respectively; S2, mixing hydrophobic nano-silica with isopropyl alcohol, and subjecting the mixture to ultrasonic dispersion treatment to obtain the nano-silica pre-dispersed slurry; S3, preparing a microencapsulated foaming agent; S4, compounding and mixing the foaming module solution, the foam stabilizing module solution, the anti-interference module solution, the nano-silica pre-dispersed slurry and the microencapsulated foaming agent; S5. Ripening the compounded mixture to obtain the gas well foaming agent.

6. The method for preparing the gas well foaming agent according to claim 5, wherein: The specific steps of preparing the foaming module solution, the foam stabilizing module solution and the anti-interference module solution are as follows: Add deionized water to the reactor, heat to 45 to 55 degrees Celsius, add sodium α-olefin sulfonate under stirring until it is completely dissolved to obtain a foaming module solution; Deionized water was added to the second reactor, and hydroxypropyl guar gum was added at a shear rate of 2,000 rpm. The shearing was continued for 30 minutes, and the shear rate was reduced to 500 rpm. Lauramide propylamine oxide was added and stirred for 60 minutes to obtain a foam stabilizing module solution. Add the block polyether and ethoxylated sulfonate to the third reactor, heat to 55 to 65 degrees Celsius and stir until melt mixed; Add citric acid and benzotriazole, stir and dissolve, and obtain an anti-interference module solution.

7. The method for preparing the gas well foaming agent according to claim 6, wherein: The specific steps of preparing the microencapsulated foaming agent are as follows: Take part of the foaming module solution and add the temperature-sensitive monomer to dissolve to form the core material; The core material is added to an aqueous solution of gelatin and gum arabic at 45 degrees Celsius and a pH value of 4.5, and coated to form microcapsules through a complex coacervation reaction; After gelation, cross-linking and solidification, filtration, washing and drying, a powdery microencapsulated foaming agent is obtained.

8. The method for preparing the gas well foaming agent according to claim 7, wherein: The specific steps of compounding and mixing are: The remaining foaming module solution was transferred to the finished product reactor, and the foam stabilizing module solution and the anti-interference module solution were added in sequence under stirring and mixed evenly; adding the nano-silica pre-dispersed slurry under shearing; The microencapsulated foaming agent was added with stirring.

9. An application of a gas well foaming agent, comprising a method for preparing the gas well foaming agent according to any one of claims 2 to 8, characterized in that: The gas well foaming agent is used for drainage and gas recovery operations in gas wells with high condensate oil content, wherein the hydrophobic nano-silica and the block polyether act synergistically to form a stable barrier at the gas-liquid interface, thereby inhibiting the condensate oil from damaging the foam film.

10. An application of a gas well foaming agent, comprising the method for preparing the gas well foaming agent according to any one of claims 2 to 8, characterized in that: The gas well foaming agent is used for drainage and gas recovery operations in high-temperature and high-salinity gas wells, wherein the microencapsulated foaming agent is triggered to release under a high-temperature environment at the bottom of the well, and the ethoxylated sulfonate and citric acid act synergistically to maintain the activity of the surfactant in a high-salinity environment.