Temporary plugging well killing fluid and preparation method thereof

Abstract

The invention relates to the technical field of oil and gas construction downhole operation, in particular to a temporary plugging well killing fluid and a preparation method thereof, and the temporary plugging well killing fluid comprises 1-2% of a first component, 1.5-2.0% of a second component, 2.0-3.0% of a third component, 2.5-3.5% of a fourth component, 1.0-1.5% of a fifth component, 0.5-1.0% of an oil-soluble temporary plugging agent, 0.1-0.5% of cellulose, 0.1-0.5% of lignosulfonate and the balance of well killing fluid. The high-efficiency clay water-absorbing agent provided by the invention has a water-absorbing main agent material with relatively good fluidity, relatively strong pressure-bearing capacity and certain viscosity, and an efficient clay stabilizer. The temporary plugging well killing fluid can be rapidly prepared on site, the construction process is simple and convenient, the temporary plugging well killing fluid provided by the invention can meet injection and flowback processes of well repair of different types of oil and gas wells, oil and gas channels near a well hole in the well repair process can be effectively plugged, and smooth operation of well repair operation is maintained.

Description

Technical Field

[0001] This invention relates to the field of downhole operations technology in oil and gas construction, specifically to a temporary plugging and control fluid and its preparation method. Background Technology

[0002] To reduce well kill fluid loss and water lock damage during well workover, the design concept of the well kill fluid is to use a water-proof / water-absorbing material with a certain pressure-bearing capacity to isolate the flow channel between the reservoir and the liquid in the wellbore, while using a high-efficiency clay stabilizer to prevent the expansion and migration of clay particles and reduce damage to the reservoir.

[0003] Current temporary plugging and kill fluids using ordinary gels and their composite plugging agents exhibit significant viscosity and poor temperature resistance, making their pressure-bearing capacity unsuitable for downhole working environments in formations with ultra-low pressure coefficients. Pluging agents with added solid materials suffer from poor flowback performance, resulting in poor production recovery in low-pressure, low-production fractured gas wells. Autodegradable temporary plugging gels, with their biodegradable fibers, only reinforce the colloid and do not provide adaptive sealing to the producing formation. Furthermore, colloids cross-linked with amphoteric metal ion cross-linking agents generally have low temperature resistance and poor high-temperature adaptability. Summary of the Invention

[0004] Based on this, the present invention proposes a temporary plugging and killing fluid and its preparation method to effectively seal the oil and gas passages near the wellbore during the well workover process and maintain the smooth operation of the well workover operation.

[0005] According to a first aspect of the present invention, a temporary plugging and kill fluid is provided, comprising, by weight percentage:

[0006] The composition consists of 1-2% of the first component, 1.5-2.0% of the second component, 2.0-3.0% of the third component, 2.5-3.5% of the fourth component, 1.0-1.5% of the fifth component, 0.5-1.0% of an oil-soluble temporary plugging agent, 0.1-0.5% of cellulose and 0.1-0.5% of lignin sulfonate, with the remaining components being the kill fluid.

[0007] According to an embodiment of the present invention, the first component comprises, by weight parts:

[0008] 10-15 parts by weight of lignin sulfonate, 15-20 parts by weight of polyvinylpyrrolidone, 5-10 parts by weight of graphene oxide, 10-15 parts by weight of dimethyl sulfoxide, 20-25 parts by weight of glycerol complex aqueous solution, 10-15 parts by weight of oxidized alginate, 15-20 parts by weight of acrylamide, 15-20 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 10-15 parts by weight of polyetheramine, 5-10 parts by weight of 1-butyl-3-methylimidazolium hydrogen sulfate, and 10-20 parts by weight of nano-silica;

[0009] And / or, the second component comprises, by weight parts:

[0010] 10-15 parts by weight of 2-(acryloyloxy)ethyltrimethylammonium chloride, 10-15 parts by weight of 2-phenoxyethyl acrylate, 5-10 parts by weight of diethylacrylamide, 10-15 parts by weight of 3-dimethyl(methacryloyloxyethyl)propanesulfonate ammonium, 10-15 parts by weight of poly(β-cyclodextrin), 10-15 parts by weight of benzimidazole, 15-20 parts by weight of dimethyl sulfoxide, 5-10 parts by weight of montmorillonite, 10-20 parts by weight of cellulose nanofibers, 1-3 parts by weight of methylenebisacrylamide, and 1-3 parts by weight of azobisisobutylamidine.

[0011] According to an embodiment of the present invention, the third component comprises a first solution and a second solution mixed in a mass ratio of 1:3;

[0012] The first solution comprises, by weight parts: 20-30 parts sodium dodecyl diphenyl ether disulfonate, 100-120 parts deionized water, 1-3 parts acrylic acid, 5-8 parts styrene, 3-5 parts butyl acrylate, 3-6 parts isooctyl acrylate, 0.3 parts ammonium persulfate, and 0.25-0.5 parts sodium bicarbonate;

[0013] The second solution comprises, by weight parts: 2-5 parts sodium dodecyl diphenyl ether disulfonate, 80-100 parts deionized water, 3-5 parts acrylic acid, 6-8 parts styrene, 5-8 parts butyl acrylate, 6-9 parts isooctyl acrylate, 0.5-1 parts ammonium persulfate, and 0.5-1 parts sodium bicarbonate.

[0014] According to an embodiment of the present invention, the fourth component includes a first particle, a second particle, and a third particle;

[0015] The mass ratio of the first particle, the second particle, and the third particle is 1:1:2 to 1:2:4;

[0016] The first particle is a powder obtained by centrifugation and drying of 40-60 parts by weight of polylactic acid and 20-30 parts by weight of microcrystalline cellulose.

[0017] The second particle comprises, by weight parts: 10-20 parts cyanuric acid, 5-10 parts ammonium polyphosphate, 30-50 parts anhydrous ethanol and 15-20 parts melamine;

[0018] The third particle, by weight parts, comprises: 50-80 parts poly(butylene adipate / terephthalate), 40-60 parts polycaprolactone, 20 parts γ-aminopropyltriethoxysilane, 5-10 parts pentaerythritol ester, 5-10 parts phosphite, and 25-40 parts polyethylene glycol.

[0019] According to an embodiment of the present invention, the fifth component comprises, by weight, the following:

[0020] 20-30 parts by weight of melamine polyphosphate, 10-20 parts by weight of diethyl phthalate, 100 parts by weight of deionized water, 10-20 parts by weight of β-cyclodextrin, 5-10 parts by weight of urea, 5-10 parts by weight of isocyanate, 1 part by weight of γ-aminopropyltriethoxysilane, 20-30 parts by weight of aluminum diethylphosphinate, 10 parts by weight of silicone-acrylic emulsion, 10-20 parts by weight of silicone oil, and 10-20 parts by weight of ethylene-acetic acid. The mixture comprises: ethylene ester emulsion, 20-30 parts by weight of styrene-acrylate copolymer emulsion, 5-10 parts by weight of alcohol ester dodecyl (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 2-5 parts by weight of sodium hexametaphosphate, 10-15 parts by weight of γ-aminopropyltriethoxysilane, 2-5 parts by weight of dimethylolpropionic acid, 5-10 parts by weight of polypropylene glycol, 5-10 parts by weight of 1,4-butanediol, and 10-20 parts by weight of triethylamine.

[0021] According to a second aspect of the present invention, a method for preparing the above-mentioned temporary plugging and killing fluid is provided, comprising the following steps:

[0022] Preparation of the first component;

[0023] Preparation of the second component;

[0024] Preparation of the third component;

[0025] Preparation of the fourth component;

[0026] Preparation of the fifth component;

[0027] The temporary plugging and killing fluid is obtained by uniformly mixing the first component (1.0-2.0%), the second component (1.5-2.0%), the third component (2.0-3.0%), the fourth component (2.5-3.5%), the fifth component (1.0-1.5%), 0.5-1.0% oil-soluble temporary plugging agent, 0.1-0.5% cellulose, and 0.1-0.5% lignin sulfonate with the kill fluid.

[0028] According to an embodiment of the present invention, the preparation of the first component includes:

[0029] 10-15 parts by weight of lignin sulfonate, 15-20 parts by weight of polyvinylpyrrolidone, and 5-10 parts by weight of graphene oxide were placed in a composite aqueous solution of 10-15 parts by weight of dimethyl sulfoxide and 20-25 parts by weight of glycerol. After reacting at 70°C for 2 hours, 10-15 parts by weight of oxidized alginate, 15-20 parts by weight of acrylamide, 15-20 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 10-15 parts by weight of polyetheramine, 5-10 parts by weight of 1-butyl-3-methylimidazolium hydrogen sulfate, and 10-20 parts by weight of nano-silica were added, and the reaction was continued for 6 hours to obtain the first component.

[0030] The preparation of the second component includes: mixing 10-15 parts by weight of 2-(acryloyloxy)ethyltrimethylammonium chloride, 10-15 parts by weight of 2-phenoxyethyl acrylate, 5-10 parts by weight of diethylacrylamide, 10-15 parts by weight of 3-dimethyl(methacryloyloxyethyl)propanesulfonate ammonium, 10-15 parts by weight of poly(β-cyclodextrin), 10-15 parts by weight of benzimidazole, and 15-20 parts by weight of dimethyl sulfoxide evenly; adding 5-10 parts by weight of montmorillonite and 10-20 parts by weight of cellulose nanofibers and mixing evenly; adding 1-3 parts by weight of methylenebisacrylamide and 1-3 parts by weight of azobisisobutylamidine; heating at 80°C for 6 hours; drying and pulverizing into 60-120 mesh particles to obtain the second component.

[0031] According to an embodiment of the present invention, the preparation of the third component includes:

[0032] Preparation of the first solution: 20-30 parts by weight of sodium dodecyl diphenyl ether disulfonate and 100-120 parts by weight of deionized water were mixed evenly. 1-3 parts by weight of acrylic acid, 5-8 parts by weight of styrene, 3-5 parts by weight of butyl acrylate, and 3-6 parts by weight of isooctyl acrylate were added. The mixture was emulsified at 300 r / min for 30 min. At 85°C, 0.3 parts by weight of ammonium persulfate and 0.25-0.5 parts by weight of sodium bicarbonate were added. The reaction was carried out for 6 hours. Ammonia water was added dropwise to adjust the pH to 8 to obtain the first solution.

[0033] Preparation of the second solution: Mix 2-5 parts by weight of sodium dodecyl diphenyl ether disulfonate and 80-100 parts by weight of deionized water evenly, add 3-5 parts by weight of acrylic acid, 6-8 parts by weight of styrene, 5-8 parts by weight of butyl acrylate and 6-9 parts by weight of isooctyl acrylate, emulsify at 300 r / min for 30 min, add 0.5-1 parts by weight of ammonium persulfate and 0.5-1 parts by weight of sodium bicarbonate at 85℃, react for 6 hours, and adjust the pH to 8 by adding ammonia water dropwise to obtain the second solution;

[0034] The third component is obtained by mixing the first solution and the second solution in a 1:3 ratio.

[0035] According to an embodiment of the present invention, the preparation of the fourth component includes:

[0036] Preparation of the first particle: 40-60 parts by weight of polylactic acid and 20-30 parts by weight of microcrystalline cellulose are dispersed in deionized water, added to a ball mill, the rotor speed is 3000 r / min, the temperature is 25℃, the ball milling time is 3h, and the powder is obtained by centrifugation and drying, thus obtaining the first particle;

[0037] Preparation of the second particle: 10-20 parts by weight of cyanuric acid, 5-10 parts by weight of ammonium polyphosphate, and 30-50 parts by weight of anhydrous ethanol were placed in a three-necked flask, heated to 80°C, and stirred for 2 hours; then 15-20 parts by weight of melamine were added, and the reaction was carried out for 12 hours. The mixture was dried to obtain the second particle.

[0038] Preparation of the third particle: Add 50-80 parts by weight of poly(butylene adipate / terephthalate), 40-60 parts by weight of polycaprolactone, 20 parts by weight of γ-aminopropyltriethoxysilane, 5-10 parts by weight of pentaerythritol ester, 5-10 parts by weight of phosphite, and 25-40 parts by weight of polyethylene glycol into a twin-screw extruder and melt-blend extrude at 130°C. Pulverize into 50-100 mesh powder to obtain the third particle.

[0039] According to an embodiment of the present invention, the preparation of the fifth component includes:

[0040] 20-30 parts by weight of melamine polyphosphate, 10-20 parts by weight of diethyl phthalate and 100 parts by weight of deionized water are dissolved in a beaker and mixed evenly. The mixture is then heated in a water bath at 70°C for 30 minutes to obtain the first mixture.

[0041] Add 10-20 parts by weight of β-cyclodextrin, 5-10 parts by weight of urea, 5-10 parts by weight of isocyanate, 1 part by weight of γ-aminopropyltriethoxysilane, and 20-30 parts by weight of aluminum diethylphosphinate to the first mixture in sequence into a beaker, and stir at 1000 rpm for 10 min. Then, add 10 parts by weight of silicone-acrylic emulsion to the solution and stir for 20 min to obtain the second mixture.

[0042] Add 10-20 parts by weight of silicone oil and organosilicon, 10-20 parts by weight of ethylene-vinyl acetate emulsion, 20-30 parts by weight of styrene-acrylate copolymer emulsion, 5-10 parts by weight of alcohol ester dodecyl (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 2-5 parts by weight of sodium hexametaphosphate, 10-15 parts by weight of γ-aminopropyltriethoxysilane (KH550), 2-5 parts by weight of dimethylolpropionic acid, 5-10 parts by weight of polypropylene glycol and 5-10 parts by weight of 1,4-butanediol, and 10-20 parts by weight of triethylamine to the second mixture. Stir the solution for 30 minutes to obtain a homogeneous emulsion, which is the fifth component.

[0043] As can be seen from the above technical solutions, the temporary plugging and killing fluid and its preparation method provided by the present invention have the following beneficial effects:

[0044] This invention features a water-absorbing main agent with good fluidity, strong pressure resistance, and a certain viscosity, along with a highly efficient clay stabilizer. It allows for rapid on-site preparation and simplifies the construction process. The temporary plugging and killing fluid provided by this invention can meet the injection and flowback requirements of different types of oil and gas well workover processes, effectively sealing oil and gas channels near the wellbore during the workover process and maintaining the smooth operation of the workover operation. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0046] According to a first aspect of the present invention, a temporary plugging and kill fluid is provided, comprising, by weight percentage:

[0047] The composition consists of 1-2% of the first component, 1.5-2.0% of the second component, 2.0-3.0% of the third component, 2.5-3.5% of the fourth component, 1.0-1.5% of the fifth component, 0.5-1.0% of an oil-soluble temporary plugging agent, 0.1-0.5% of cellulose and 0.1-0.5% of lignin sulfonate, with the remaining components being the kill fluid.

[0048] According to embodiments of the present invention, the first component can effectively seal micro- and nano-sized pores in the reservoir; the second component can seal larger pores or fractures in the reservoir; the third component is an emulsion plugging agent that can increase the sealing performance of the kill fluid system on the core surface through adsorption; the fourth component, while sealing reservoir pores, has certain self-degradation properties, which is beneficial for restoring reservoir permeability after a period of sealing; and the fifth component can form a film-like substance on the core surface, further increasing the sealing effect on the rock surface.

[0049] According to an embodiment of the present invention, the first component comprises, by weight parts:

[0050] 10-15 parts by weight of lignin sulfonate, 15-20 parts by weight of polyvinylpyrrolidone, 5-10 parts by weight of graphene oxide, 10-15 parts by weight of dimethyl sulfoxide, 20-25 parts by weight of glycerol complex aqueous solution, 10-15 parts by weight of oxidized alginate, 15-20 parts by weight of acrylamide, 15-20 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 10-15 parts by weight of polyetheramine, 5-10 parts by weight of 1-butyl-3-methylimidazolium hydrogen sulfate, and 10-20 parts by weight of nano-silica;

[0051] And / or, the second component comprises, by weight parts:

[0052] 10-15 parts by weight of 2-(acryloyloxy)ethyltrimethylammonium chloride, 10-15 parts by weight of 2-phenoxyethyl acrylate, 5-10 parts by weight of diethylacrylamide, 10-15 parts by weight of 3-dimethyl(methacryloyloxyethyl)propanesulfonate ammonium, 10-15 parts by weight of poly(β-cyclodextrin), 10-15 parts by weight of benzimidazole, 15-20 parts by weight of dimethyl sulfoxide, 5-10 parts by weight of montmorillonite, 10-20 parts by weight of cellulose nanofibers, 1-3 parts by weight of methylenebisacrylamide, and 1-3 parts by weight of azobisisobutylamidine.

[0053] According to an embodiment of the present invention, the third component comprises a first solution and a second solution mixed in a mass ratio of 1:3;

[0054] The first solution comprises, by weight parts: 20-30 parts sodium dodecyl diphenyl ether disulfonate, 100-120 parts deionized water, 1-3 parts acrylic acid, 5-8 parts styrene, 3-5 parts butyl acrylate, 3-6 parts isooctyl acrylate, 0.3 parts ammonium persulfate, and 0.25-0.5 parts sodium bicarbonate;

[0055] The second solution comprises, by weight parts: 2-5 parts sodium dodecyl diphenyl ether disulfonate, 80-100 parts deionized water, 3-5 parts acrylic acid, 6-8 parts styrene, 5-8 parts butyl acrylate, 6-9 parts isooctyl acrylate, 0.5-1 parts ammonium persulfate, and 0.5-1 parts sodium bicarbonate.

[0056] According to an embodiment of the present invention, the fourth component includes a first particle, a second particle, and a third particle;

[0057] The mass ratio of the first particle, the second particle, and the third particle is 1:1:2 to 1:2:4;

[0058] The first particle is a powder obtained by centrifugation and drying of 40-60 parts by weight of polylactic acid and 20-30 parts by weight of microcrystalline cellulose.

[0059] The second particle comprises, by weight parts: 10-20 parts cyanuric acid, 5-10 parts ammonium polyphosphate, 30-50 parts anhydrous ethanol and 15-20 parts melamine;

[0060] The third particle, by weight parts, comprises: 50-80 parts poly(butylene adipate / terephthalate), 40-60 parts polycaprolactone, 20 parts γ-aminopropyltriethoxysilane, 5-10 parts pentaerythritol ester, 5-10 parts phosphite, and 25-40 parts polyethylene glycol.

[0061] According to an embodiment of the present invention, the fifth component comprises, by weight, the following:

[0062] 20-30 parts by weight of melamine polyphosphate, 10-20 parts by weight of diethyl phthalate, 100 parts by weight of deionized water, 10-20 parts by weight of β-cyclodextrin, 5-10 parts by weight of urea, 5-10 parts by weight of isocyanate, 1 part by weight of γ-aminopropyltriethoxysilane, 20-30 parts by weight of aluminum diethylphosphinate, 10 parts by weight of silicone-acrylic emulsion, 10-20 parts by weight of silicone oil, and 10-20 parts by weight of ethylene-acetic acid. The mixture comprises: ethylene ester emulsion, 20-30 parts by weight of styrene-acrylate copolymer emulsion, 5-10 parts by weight of alcohol ester dodecyl (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 2-5 parts by weight of sodium hexametaphosphate, 10-15 parts by weight of γ-aminopropyltriethoxysilane, 2-5 parts by weight of dimethylolpropionic acid, 5-10 parts by weight of polypropylene glycol, 5-10 parts by weight of 1,4-butanediol, and 10-20 parts by weight of triethylamine.

[0063] According to a second aspect of the present invention, a method for preparing the above-mentioned temporary plugging and killing fluid is provided, comprising the following steps:

[0064] Preparation of the first component;

[0065] Preparation of the second component;

[0066] Preparation of the third component;

[0067] Preparation of the fourth component;

[0068] Preparation of the fifth component;

[0069] The temporary plugging and killing fluid is obtained by uniformly mixing the first component (1.0-2.0%), the second component (1.5-2.0%), the third component (2.0-3.0%), the fourth component (2.5-3.5%), the fifth component (1.0-1.5%), 0.5-1.0% oil-soluble temporary plugging agent, 0.1-0.5% cellulose, and 0.1-0.5% lignin sulfonate with the kill fluid.

[0070] According to an embodiment of the present invention, the preparation of the first component includes:

[0071] 10-15 parts by weight of lignin sulfonate, 15-20 parts by weight of polyvinylpyrrolidone, and 5-10 parts by weight of graphene oxide were placed in a composite aqueous solution of 10-15 parts by weight of dimethyl sulfoxide and 20-25 parts by weight of glycerol. After reacting at 70°C for 2 hours, 10-15 parts by weight of oxidized alginate, 15-20 parts by weight of acrylamide, 15-20 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 10-15 parts by weight of polyetheramine, 5-10 parts by weight of 1-butyl-3-methylimidazolium hydrogen sulfate, and 10-20 parts by weight of nano-silica were added, and the reaction was continued for 6 hours to obtain the first component.

[0072] The preparation of the second component includes: mixing 10-15 parts by weight of 2-(acryloyloxy)ethyltrimethylammonium chloride, 10-15 parts by weight of 2-phenoxyethyl acrylate, 5-10 parts by weight of diethylacrylamide, 10-15 parts by weight of 3-dimethyl(methacryloyloxyethyl)propanesulfonate ammonium, 10-15 parts by weight of poly(β-cyclodextrin), 10-15 parts by weight of benzimidazole, and 15-20 parts by weight of dimethyl sulfoxide evenly; adding 5-10 parts by weight of montmorillonite and 10-20 parts by weight of cellulose nanofibers and mixing evenly; adding 1-3 parts by weight of methylenebisacrylamide and 1-3 parts by weight of azobisisobutylamidine; heating at 80°C for 6 hours; drying and pulverizing into 60-120 mesh particles to obtain the second component.

[0073] According to an embodiment of the present invention, the preparation of the third component includes:

[0074] Preparation of the first solution: 20-30 parts by weight of sodium dodecyl diphenyl ether disulfonate and 100-120 parts by weight of deionized water were mixed evenly. 1-3 parts by weight of acrylic acid, 5-8 parts by weight of styrene, 3-5 parts by weight of butyl acrylate, and 3-6 parts by weight of isooctyl acrylate were added. The mixture was emulsified at 300 r / min for 30 min. At 85°C, 0.3 parts by weight of ammonium persulfate and 0.25-0.5 parts by weight of sodium bicarbonate were added. The reaction was carried out for 6 hours. Ammonia water was added dropwise to adjust the pH to 8 to obtain the first solution.

[0075] Preparation of the second solution: Mix 2-5 parts by weight of sodium dodecyl diphenyl ether disulfonate and 80-100 parts by weight of deionized water evenly, add 3-5 parts by weight of acrylic acid, 6-8 parts by weight of styrene, 5-8 parts by weight of butyl acrylate and 6-9 parts by weight of isooctyl acrylate, emulsify at 300 r / min for 30 min, add 0.5-1 parts by weight of ammonium persulfate and 0.5-1 parts by weight of sodium bicarbonate at 85℃, react for 6 hours, and adjust the pH to 8 by adding ammonia water dropwise to obtain the second solution;

[0076] The third component is obtained by mixing the first solution and the second solution in a 1:3 ratio.

[0077] According to an embodiment of the present invention, the preparation of the fourth component includes:

[0078] Preparation of the first particle: 40-60 parts by weight of polylactic acid and 20-30 parts by weight of microcrystalline cellulose are dispersed in deionized water, added to a ball mill, the rotor speed is 3000 r / min, the temperature is 25℃, the ball milling time is 3h, and the powder is obtained by centrifugation and drying, thus obtaining the first particle;

[0079] Preparation of the second particle: 10-20 parts by weight of cyanuric acid, 5-10 parts by weight of ammonium polyphosphate, and 30-50 parts by weight of anhydrous ethanol were placed in a three-necked flask, heated to 80°C, and stirred for 2 hours; then 15-20 parts by weight of melamine were added, and the reaction was carried out for 12 hours. The mixture was dried to obtain the second particle.

[0080] Preparation of the third particle: Add 50-80 parts by weight of poly(butylene adipate / terephthalate), 40-60 parts by weight of polycaprolactone, 20 parts by weight of γ-aminopropyltriethoxysilane, 5-10 parts by weight of pentaerythritol ester, 5-10 parts by weight of phosphite, and 25-40 parts by weight of polyethylene glycol into a twin-screw extruder and melt-blend extrude at 130°C. Pulverize into 50-100 mesh powder to obtain the third particle.

[0081] According to an embodiment of the present invention, the preparation of the fifth component includes:

[0082] 20-30 parts by weight of melamine polyphosphate, 10-20 parts by weight of diethyl phthalate and 100 parts by weight of deionized water are dissolved in a beaker and mixed evenly. The mixture is then heated in a water bath at 70°C for 30 minutes to obtain the first mixture.

[0083] Add 10-20 parts by weight of β-cyclodextrin, 5-10 parts by weight of urea, 5-10 parts by weight of isocyanate, 1 part by weight of γ-aminopropyltriethoxysilane, and 20-30 parts by weight of aluminum diethylphosphinate to the first mixture in sequence into a beaker, and stir at 1000 rpm for 10 min. Then, add 10 parts by weight of silicone-acrylic emulsion to the solution and stir for 20 min to obtain the second mixture.

[0084] Add 10-20 parts by weight of silicone oil and organosilicon, 10-20 parts by weight of ethylene-vinyl acetate emulsion, 20-30 parts by weight of styrene-acrylate copolymer emulsion, 5-10 parts by weight of alcohol ester dodecyl (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 2-5 parts by weight of sodium hexametaphosphate, 10-15 parts by weight of γ-aminopropyltriethoxysilane (KH550), 2-5 parts by weight of dimethylolpropionic acid, 5-10 parts by weight of polypropylene glycol and 5-10 parts by weight of 1,4-butanediol, and 10-20 parts by weight of triethylamine to the second mixture. Stir the solution for 30 minutes to obtain a homogeneous emulsion, which is the fifth component.

[0085] The technical solution of the present invention will be described in detail below through preferred embodiments. It should be noted that the specific embodiments in the following text are for illustrative purposes only and are not intended to limit the present invention.

[0086] Example 1

[0087] 1.0% first component, 1.5% second component, 2.0% third component, 2.5% fourth component, 1.0% fifth component and 0.5% oil-soluble temporary plugging agent, the remaining components are well kill fluid.

[0088] First component:

[0089] 10 parts by weight of lignin sulfonate, 150 parts by weight of polyvinylpyrrolidone, and 5 parts by weight of graphene oxide were placed in a composite aqueous solution of 10 parts by weight of dimethyl sulfoxide and 20 parts by weight of glycerol, and the mixture was heated to 70°C and reacted for 2 hours. Then, 10 parts by weight of oxidized alginate, 15 parts by weight of acrylamide, 15 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 10 parts by weight of polyetheramine, 5 parts by weight of 1-butyl-3-methylimidazolium hydrogen sulfate, and 10 parts by weight of nano-silica were added, and the reaction was continued for 6 hours to obtain the first component.

[0090] Second component:

[0091] Ten parts by weight of 2-(acryloyloxy)ethyltrimethylammonium chloride, ten parts by weight of 2-phenoxyethyl acrylate, five parts by weight of diethylacrylamide, ten parts by weight of 3-dimethyl(methacryloyloxyethyl)propanesulfonate ammonium, ten parts by weight of poly(β-cyclodextrin), ten parts by weight of benzimidazole, and 15 parts by weight of dimethyl sulfoxide were mixed evenly. Five parts by weight of montmorillonite and ten parts by weight of cellulose nanofibers were added and mixed evenly. One part by weight of methylenebisacrylamide and one part by weight of azobisisobutylamidine were added, and the mixture was heated at 80°C for 6 hours. The mixture was then dried and pulverized into 60-120 mesh particles to obtain the second component.

[0092] Third component:

[0093] (1) Mix 20 parts by weight of sodium dodecyl diphenyl ether disulfonate and 100 parts by weight of deionized water evenly, add 1 part by weight of acrylic acid, 5 parts by weight of styrene, 3 parts by weight of butyl acrylate and 3 parts by weight of isooctyl acrylate, and emulsify at 300 r / min for 30 min. At 85℃, add 0.3 parts by weight of ammonium persulfate and 0.25 parts by weight of sodium bicarbonate, react for 6 hours, and adjust the pH to 8 by adding ammonia dropwise to obtain the first solution.

[0094] (2) Mix 2 parts by weight of sodium dodecyl diphenyl ether disulfonate and 80 parts by weight of deionized water evenly, add 3 parts by weight of acrylic acid, 6 parts by weight of styrene, 5 parts by weight of butyl acrylate and 6 parts by weight of isooctyl acrylate, and emulsify at 300 r / min for 30 min. At 85℃, add 0.5 parts by weight of ammonium persulfate and 0.5 parts by weight of sodium bicarbonate, react for 6 hours, and adjust the pH to 8 by adding ammonia dropwise to obtain the second solution.

[0095] (3) The first solution and the second solution are mixed in a ratio of 1:3 to obtain the third component.

[0096] Fourth component:

[0097] (1) Disperse 40 parts by weight of polylactic acid and 20 parts by weight of microcrystalline cellulose in deionized water, add them to a ball mill, the rotor speed is 3000 r / min, the temperature is 25℃, the ball milling time is 3h, and the powder is obtained by centrifugation and drying to obtain the first particle.

[0098] (2) Add 10 parts by weight of cyanuric acid, 5 parts by weight of ammonium polyphosphate, and 30 parts by weight of anhydrous ethanol to a three-necked flask, heat to 80°C, and stir for 2 hours; then add 15-20 parts by weight of melamine and react for 12 hours. Dry to obtain a solid, thus obtaining the second particle.

[0099] (3) Add 50 parts by weight of poly(butylene adipate / terephthalate), 40 parts by weight of polycaprolactone, 20 parts by weight of γ-aminopropyltriethoxysilane (KH550), 5 parts by weight of pentaerythritol ester, 5 parts by weight of phosphite ester, and 25 parts by weight of polyethylene glycol into a twin-screw extruder and melt-blend extrusion at 130°C. Crush the mixture into 50-mesh powder to obtain the third particle.

[0100] Fifth component:

[0101] (1) First, 20 parts by weight of melamine polyphosphate, 10 parts by weight of diethyl phthalate and 100 parts by weight of deionized water are dissolved in a beaker and mixed evenly. The mixture is then heat-treated in a water bath (70°C) for 30 minutes to obtain the first mixture.

[0102] (2) Add 10 parts by weight of β-cyclodextrin, 5 parts by weight of urea, 5 parts by weight of isocyanate, 1 part by weight of γ-aminopropyltriethoxysilane, and 20 parts by weight of aluminum diethylphosphinate to the first mixture in a beaker, and stir at 1000 rpm for 10 min. Then, add 10 parts by weight of silicone-acrylic emulsion to the solution and stir for 20 min to obtain the second mixture.

[0103] (3) Add 10 parts by weight of silicone oil, 10 parts by weight of ethylene-vinyl acetate emulsion, 20 parts by weight of styrene-acrylate copolymer emulsion, 5 parts by weight of alcohol ester dodecyl (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 2 parts by weight of sodium hexametaphosphate, 10 parts by weight of γ-aminopropyltriethoxysilane (KH550), 2 parts by weight of dimethylolpropionic acid, 5 parts by weight of polypropylene glycol and 5 parts by weight of 1,4-butanediol, and 10 parts by weight of triethylamine to the second mixture. Stir the solution for 30 minutes to obtain a uniform emulsion, which is the fifth component.

[0104] Example 2

[0105] It includes 2.0% first component, 2.0% second component, 2.0% third component, 2.0% fourth component, 1.5% fifth component, and 0.5% oil-soluble temporary plugging agent, with the remaining components being well-killing fluid.

[0106] First component:

[0107] 15 parts by weight of lignin sulfonate, 20 parts by weight of polyvinylpyrrolidone, and 10 parts by weight of graphene oxide were placed in a composite aqueous solution of 15 parts by weight of dimethyl sulfoxide and 25 parts by weight of glycerol, and the mixture was heated to 70°C and reacted for 2 hours. Then, 15 parts by weight of oxidized alginate, 20 parts by weight of acrylamide, 20 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 15 parts by weight of polyetheramine, 10 parts by weight of 1-butyl-3-methylimidazolium hydrogen sulfate, and 20 parts by weight of nano-silica were added, and the reaction was continued for 6 hours to obtain the first component.

[0108] Second component:

[0109] 15 parts by weight of 2-(acryloyloxy)ethyltrimethylammonium chloride, 15 parts by weight of 2-phenoxyethyl acrylate, 10 parts by weight of diethylacrylamide, 15 parts by weight of 3-dimethyl(methacryloyloxyethyl)propanesulfonate ammonium, 15 parts by weight of poly(β-cyclodextrin), 15 parts by weight of benzimidazole, and 20 parts by weight of dimethyl sulfoxide were mixed evenly. Then, 10 parts by weight of montmorillonite and 20 parts by weight of cellulose nanofibers were added and mixed evenly. Finally, 3 parts by weight of methylenebisacrylamide and 3 parts by weight of azobisisobutylamidine were added, and the mixture was heated at 80°C for 6 hours. The mixture was then dried and pulverized into 60-120 mesh particles to obtain the second component.

[0110] Third component:

[0111] (1) Mix 30 parts by weight of sodium dodecyl diphenyl ether disulfonate and 120 parts by weight of deionized water evenly, add 3 parts by weight of acrylic acid, 8 parts by weight of styrene, 5 parts by weight of butyl acrylate and 6 parts by weight of isooctyl acrylate, and emulsify at 300 r / min for 30 min. At 85℃, add 0.3 parts by weight of ammonium persulfate and 0.5 parts by weight of sodium bicarbonate, react for 6 hours, and adjust the pH to 8 by adding ammonia water dropwise to obtain the first solution.

[0112] (2) Mix 5 parts by weight of sodium dodecyl diphenyl ether disulfonate and 100 parts by weight of deionized water evenly, add 5 parts by weight of acrylic acid, 8 parts by weight of styrene, 8 parts by weight of butyl acrylate and 9 parts by weight of isooctyl acrylate, and emulsify at 300 r / min for 30 min. At 85℃, add 1 part by weight of ammonium persulfate and 1 part by weight of sodium bicarbonate, react for 6 hours, and adjust the pH to 8 by adding ammonia water dropwise to obtain the second solution.

[0113] (3) The first solution and the second solution are mixed in a ratio of 1:3 to obtain the third component.

[0114] Fourth component:

[0115] (1) Disperse 60 parts by weight of polylactic acid and 30 parts by weight of microcrystalline cellulose in deionized water, add them to a ball mill, the rotor speed is 3000 r / min, the temperature is 25℃, the ball milling time is 3h, and the powder is obtained by centrifugation and drying to obtain the first particle.

[0116] (2) Add 20 parts by weight of cyanuric acid, 10 parts by weight of ammonium polyphosphate, and 50 parts by weight of anhydrous ethanol to a three-necked flask, heat to 80°C, and stir for 2 hours; then add 20 parts by weight of melamine and react for 12 hours. Dry to obtain a solid, and the second particle is obtained.

[0117] (3) Add 80 parts by weight of poly(butylene adipate / terephthalate), 60 parts by weight of polycaprolactone, 20 parts by weight of γ-aminopropyltriethoxysilane (KH550), 10 parts by weight of pentaerythritol ester, 10 parts by weight of phosphite ester, and 40 parts by weight of polyethylene glycol into a twin-screw extruder and melt-blend extrusion at 130°C. Pulverize into 50-100 mesh powder to obtain the third particle.

[0118] Fifth component:

[0119] (1) First, 30 parts by weight of melamine polyphosphate, 20 parts by weight of diethyl phthalate and 100 parts by weight of deionized water are dissolved in a beaker and mixed evenly. The mixture is then heat-treated in a water bath (70°C) for 30 minutes to obtain the first mixture.

[0120] (2) Add 20 parts by weight of β-cyclodextrin, 10 parts by weight of urea, 10 parts by weight of isocyanate, 1 part by weight of γ-aminopropyltriethoxysilane, and 30 parts by weight of aluminum diethylphosphinate to the first mixture in a beaker, and stir at 1000 rpm for 10 min. Then, add 10 parts by weight of silicone-acrylic emulsion to the solution and stir for 20 min to obtain the second mixture.

[0121] (3) Add 20 parts by weight of silicone oil, 20 parts by weight of ethylene-vinyl acetate emulsion, 30 parts by weight of styrene-acrylate copolymer emulsion, 10 parts by weight of alcohol ester dodecyl (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 5 parts by weight of sodium hexametaphosphate, 15 parts by weight of γ-aminopropyltriethoxysilane (KH550), 5 parts by weight of dimethylolpropionic acid, 10 parts by weight of polypropylene glycol and 10 parts by weight of 1,4-butanediol, and 20 parts by weight of triethylamine to the second mixture. Stir the solution for 30 minutes to obtain a uniform emulsion, which is the fifth component.

[0122] Comparative Example 1

[0123] Other temporary plugging and kill fluid formulations, by mass fraction, include:

[0124] The composition includes 3% oil-soluble temporary plugging agent, 1.0% resin, 0.2% carboxymethyl cellulose, 0.5% bentonite, 0.2% polyacrylamide, 0.2% polyethylene polyamine, 0.1% modified starch, and 0.2%... ％ The components are imidazoline corrosion inhibitors and the remaining components are kill fluid.

[0125] Comparative Example 2

[0126] Other temporary plugging and kill fluid formulations, by mass fraction, include:

[0127] The composition consists of 4% oil-soluble temporary plugging agent, 1.0% resin, 0.2% xanthan gum, 0.3% bentonite, 0.1% polyacrylamide, 0.2% polyamino acid, 0.1% humate, and 0.2% imidazoline corrosion inhibitor. The remaining components are kill fluid.

[0128] Experimental Example 1:

[0129] Experimental steps:

[0130] Rock samples were displaced using formation water and kerosene, and the liquid phase permeability was determined. A constant medium flow rate method (or a constant displacement pressure method) was employed during displacement. The specific experimental procedure is as follows:

[0131] ① Extract oil from rock samples, dry them to constant weight at 80℃, and measure their nitrogen permeability (kg).

[0132] ② The oil phase permeability K1 of the core was determined by vacuum saturation with standard brine for 24 hours;

[0133] ③ Perform forward contamination using the prepared kill fluid system (contamination pressure differential 4MPa, temperature 120℃, time 12h);

[0134] ④Then, the oil phase permeability K2 of the core is measured in the forward direction, and the permeability plugging rate HR of the core is calculated as (K1-K2) / K1×100%.

[0135] ⑤ The core was aged at 120℃ for 120 hours, and then the reverse permeability K3 of the core was measured at 120℃ and a pressure difference of 4MPa. The permeability recovery rate DR of the core was calculated as (K3 / K1)×100%. The results are shown in Table 1.

[0136] Table 1. Comparison of the effects of temporary plugging and killing fluids in Examples 1-2 and Comparative Examples 1-2

[0137]

[0138] The above embodiments achieved a blocking rate of 99.78% and 99.80%, and a permeability recovery rate of 98.45% and 98.44%.

[0139] The aforementioned comparative examples showed plugging rates of 90.96% and 91.63%, and permeability recovery rates of 89.39% and 87.26%, respectively. This indicates that the temporary plugging and kill fluid formulation in the examples has better plugging performance, capable of forming a dense temporary plugging layer on the core surface during the kill operation. Furthermore, the higher permeability recovery rate of the examples demonstrates better reservoir protection; after the kill operation, the plugging layer can be effectively removed, restoring reservoir permeability.

[0140] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A temporary plugging and kill fluid, characterized in that, By weight percentage, including: The composition consists of 1-2% of the first component, 1.5-2.0% of the second component, 2.0-3.0% of the third component, 2.5-3.5% of the fourth component, 1.0-1.5% of the fifth component, 0.5-1.0% of an oil-soluble temporary plugging agent, 0.1-0.5% of cellulose and 0.1-0.5% of lignin sulfonate, with the remaining components being the kill fluid.

2. The temporary plugging and kill fluid according to claim 1, characterized in that, The first component, in parts by weight, comprises: 10-15 parts by weight of lignin sulfonate, 15-20 parts by weight of polyvinylpyrrolidone, 5-10 parts by weight of graphene oxide, 10-15 parts by weight of dimethyl sulfoxide, 20-25 parts by weight of glycerol complex aqueous solution, 10-15 parts by weight of oxidized alginate, 15-20 parts by weight of acrylamide, 15-20 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 10-15 parts by weight of polyetheramine, 5-10 parts by weight of 1-butyl-3-methylimidazolium hydrogen sulfate, and 10-20 parts by weight of nano-silica; And / or, the second component comprises, by weight parts: 10-15 parts by weight of 2-(acryloyloxy)ethyltrimethylammonium chloride, 10-15 parts by weight of 2-phenoxyethyl acrylate, 5-10 parts by weight of diethylacrylamide, 10-15 parts by weight of 3-dimethyl(methacryloyloxyethyl)propanesulfonate ammonium, 10-15 parts by weight of poly(β-cyclodextrin), 10-15 parts by weight of benzimidazole, 15-20 parts by weight of dimethyl sulfoxide, 5-10 parts by weight of montmorillonite, 10-20 parts by weight of cellulose nanofibers, 1-3 parts by weight of methylenebisacrylamide, and 1-3 parts by weight of azobisisobutylamidine.

3. The temporary plugging and kill fluid according to claim 1, characterized in that, The third component comprises a first solution and a second solution mixed in a mass ratio of 1:3; The first solution comprises, by weight parts: 20-30 parts sodium dodecyl diphenyl ether disulfonate, 100-120 parts deionized water, 1-3 parts acrylic acid, 5-8 parts styrene, 3-5 parts butyl acrylate, 3-6 parts isooctyl acrylate, 0.3 parts ammonium persulfate, and 0.25-0.5 parts sodium bicarbonate; The second solution comprises, by weight parts: 2-5 parts sodium dodecyl diphenyl ether disulfonate, 80-100 parts deionized water, 3-5 parts acrylic acid, 6-8 parts styrene, 5-8 parts butyl acrylate, 6-9 parts isooctyl acrylate, 0.5-1 parts ammonium persulfate, and 0.5-1 parts sodium bicarbonate.

4. The temporary plugging and kill fluid according to claim 1, characterized in that, The fourth component includes a first particle, a second particle, and a third particle; The mass ratio of the first particle, the second particle, and the third particle is 1:1:2 to 1:2:4; The first particle is a powder obtained by centrifugation and drying of 40-60 parts by weight of polylactic acid and 20-30 parts by weight of microcrystalline cellulose. The second particle comprises, by weight parts: 10-20 parts cyanuric acid, 5-10 parts ammonium polyphosphate, 30-50 parts anhydrous ethanol and 15-20 parts melamine; The third particle, by weight parts, comprises: 50-80 parts poly(butylene adipate / terephthalate), 40-60 parts polycaprolactone, 20 parts γ-aminopropyltriethoxysilane, 5-10 parts pentaerythritol ester, 5-10 parts phosphite, and 25-40 parts polyethylene glycol.

5. The temporary plugging and kill fluid according to claim 1, characterized in that, The fifth component, in parts by weight, includes: 20-30 parts by weight of melamine polyphosphate, 10-20 parts by weight of diethyl phthalate, 100 parts by weight of deionized water, 10-20 parts by weight of β-cyclodextrin, 5-10 parts by weight of urea, 5-10 parts by weight of isocyanate, 1 part by weight of γ-aminopropyltriethoxysilane, 20-30 parts by weight of aluminum diethylphosphinate, 10 parts by weight of silicone-acrylic emulsion, 10-20 parts by weight of silicone oil, and 10-20 parts by weight of ethylene-acetic acid. The mixture comprises: ethylene ester emulsion, 20-30 parts by weight of styrene-acrylate copolymer emulsion, 5-10 parts by weight of alcohol ester dodecyl (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 2-5 parts by weight of sodium hexametaphosphate, 10-15 parts by weight of γ-aminopropyltriethoxysilane, 2-5 parts by weight of dimethylolpropionic acid, 5-10 parts by weight of polypropylene glycol, 5-10 parts by weight of 1,4-butanediol, and 10-20 parts by weight of triethylamine.

6. A method for preparing the temporary plugging and killing fluid according to any one of claims 1-5, characterized in that, Includes the following steps: Preparation of the first component; Preparation of the second component; Preparation of the third component; Preparation of the fourth component; Preparation of the fifth component; The temporary plugging and killing fluid is obtained by uniformly mixing the first component (1.0-2.0%), the second component (1.5-2.0%), the third component (2.0-3.0%), the fourth component (2.5-3.5%), the fifth component (1.0-1.5%), 0.5-1.0% oil-soluble temporary plugging agent, 0.1-0.5% cellulose, and 0.1-0.5% lignin sulfonate with the kill fluid.

7. The temporary plugging and kill fluid according to claim 6, characterized in that, The preparation of the first component includes: 10-15 parts by weight of lignin sulfonate, 15-20 parts by weight of polyvinylpyrrolidone, and 5-10 parts by weight of graphene oxide were placed in a composite aqueous solution of 10-15 parts by weight of dimethyl sulfoxide and 20-25 parts by weight of glycerol. After reacting at 70°C for 2 hours, 10-15 parts by weight of oxidized alginate, 15-20 parts by weight of acrylamide, 15-20 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid, 10-15 parts by weight of polyetheramine, 5-10 parts by weight of 1-butyl-3-methylimidazolium hydrogen sulfate, and 10-20 parts by weight of nano-silica were added, and the reaction was continued for 6 hours to obtain the first component. The preparation of the second component includes: mixing 10-15 parts by weight of 2-(acryloyloxy)ethyltrimethylammonium chloride, 10-15 parts by weight of 2-phenoxyethyl acrylate, 5-10 parts by weight of diethylacrylamide, 10-15 parts by weight of 3-dimethyl(methacryloyloxyethyl)propanesulfonate ammonium, 10-15 parts by weight of poly(β-cyclodextrin), 10-15 parts by weight of benzimidazole, and 15-20 parts by weight of dimethyl sulfoxide evenly; adding 5-10 parts by weight of montmorillonite and 10-20 parts by weight of cellulose nanofibers and mixing evenly; adding 1-3 parts by weight of methylenebisacrylamide and 1-3 parts by weight of azobisisobutylamidine; heating at 80°C for 6 hours; drying and pulverizing into 60-120 mesh particles to obtain the second component.

8. The temporary plugging and kill fluid according to claim 1, characterized in that, The preparation of the third component includes: Preparation of the first solution: 20-30 parts by weight of sodium dodecyl diphenyl ether disulfonate and 100-120 parts by weight of deionized water were mixed evenly. 1-3 parts by weight of acrylic acid, 5-8 parts by weight of styrene, 3-5 parts by weight of butyl acrylate, and 3-6 parts by weight of isooctyl acrylate were added. The mixture was emulsified at 300 r / min for 30 min. At 85°C, 0.3 parts by weight of ammonium persulfate and 0.25-0.5 parts by weight of sodium bicarbonate were added. The reaction was carried out for 6 hours. Ammonia water was added dropwise to adjust the pH to 8 to obtain the first solution. Preparation of the second solution: Mix 2-5 parts by weight of sodium dodecyl diphenyl ether disulfonate and 80-100 parts by weight of deionized water evenly, add 3-5 parts by weight of acrylic acid, 6-8 parts by weight of styrene, 5-8 parts by weight of butyl acrylate and 6-9 parts by weight of isooctyl acrylate, emulsify at 300 r / min for 30 min, add 0.5-1 parts by weight of ammonium persulfate and 0.5-1 parts by weight of sodium bicarbonate at 85℃, react for 6 hours, and adjust the pH to 8 by adding ammonia water dropwise to obtain the second solution; The third component is obtained by mixing the first solution and the second solution in a 1:3 ratio.

9. The temporary plugging and kill fluid according to claim 1, characterized in that, The preparation of the fourth component includes: Preparation of the first particle: 40-60 parts by weight of polylactic acid and 20-30 parts by weight of microcrystalline cellulose are dispersed in deionized water, added to a ball mill, the rotor speed is 3000 r / min, the temperature is 25℃, the ball milling time is 3h, and the powder is obtained by centrifugation and drying, thus obtaining the first particle; Preparation of the second particle: 10-20 parts by weight of cyanuric acid, 5-10 parts by weight of ammonium polyphosphate, and 30-50 parts by weight of anhydrous ethanol were placed in a three-necked flask, heated to 80°C, and stirred for 2 hours; then 15-20 parts by weight of melamine were added, and the reaction was carried out for 12 hours. The mixture was dried to obtain the second particle. Preparation of the third particle: Add 50-80 parts by weight of poly(butylene adipate / terephthalate), 40-60 parts by weight of polycaprolactone, 20 parts by weight of γ-aminopropyltriethoxysilane, 5-10 parts by weight of pentaerythritol ester, 5-10 parts by weight of phosphite, and 25-40 parts by weight of polyethylene glycol into a twin-screw extruder and melt-blend extrude at 130°C. Pulverize into 50-100 mesh powder to obtain the third particle.

10. The temporary plugging and kill fluid according to claim 1, characterized in that, The preparation of the fifth component includes: 20-30 parts by weight of melamine polyphosphate, 10-20 parts by weight of diethyl phthalate and 100 parts by weight of deionized water are dissolved in a beaker and mixed evenly. The mixture is then heated in a water bath at 70°C for 30 minutes to obtain the first mixture. Add 10-20 parts by weight of β-cyclodextrin, 5-10 parts by weight of urea, 5-10 parts by weight of isocyanate, 1 part by weight of γ-aminopropyltriethoxysilane, and 20-30 parts by weight of aluminum diethylphosphinate to the first mixture in sequence into a beaker, and stir at 1000 rpm for 10 min. Then, add 10 parts by weight of silicone-acrylic emulsion to the solution and stir for 20 min to obtain the second mixture. Add 10-20 parts by weight of silicone oil and organosilicon, 10-20 parts by weight of ethylene-vinyl acetate emulsion, 20-30 parts by weight of styrene-acrylate copolymer emulsion, 5-10 parts by weight of alcohol ester dodecyl (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 2-5 parts by weight of sodium hexametaphosphate, 10-15 parts by weight of γ-aminopropyltriethoxysilane, 2-5 parts by weight of dimethylolpropionic acid, 5-10 parts by weight of polypropylene glycol and 5-10 parts by weight of 1,4-butanediol, and 10-20 parts by weight of triethylamine to the second mixture. Stir the solution for 30 minutes to obtain a homogeneous emulsion, which is the fifth component.

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