An impact-resistant, dilution-resistant, strong-retention, pressure-bearing and leak-stopping material, a preparation method and application thereof

Abstract

The application provides an anti-impact dilution strong retention pressure-bearing plugging material, which comprises the following raw materials in parts by mass: 100 parts of water, 0.5-2.0 parts of a water-sensitive shearing thickening plugging agent, 5-10 parts of mineral particles, 5-20 parts of composite fibers and 1-5 parts of retention material. The application also provides a preparation method and application of the anti-impact dilution strong retention pressure-bearing plugging material. The application is aimed at the active fracture and fracture-cavity type leakage of underground water, and uses the water-sensitive plugging material with the properties of 'water thickening' and'shearing thickening' as the anti-impact dilution core treatment agent; uses the elastic pore network material as the retention core treatment agent, and the small-particle shape memory material is expanded by temperature excitation at the well bottom and is captured by the elastic pore network, and the water-sensitive shearing thickening agent with good interfacial viscosity is used to further improve the retention performance of the plugging material; meanwhile, the composite mineral particles and fibers with different particle sizes and the water-sensitive shearing thickening agent with the high-elasticity gel structure establish a multi-dimensional plugging system, and the plugging effect and pressure-bearing capacity are enhanced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of drilling fluid leak stoppage materials in oil drilling engineering, and particularly relates to an anti-impact and dilution strong retention pressure-bearing leak stoppage material and a preparation method and application thereof. BACKGROUND

[0002] Fracture and cave formation malignant leakage is a major technical problem in drilling engineering, which has not been effectively solved. Although the occurrence probability of such malignant leakage accounts for only about 20% of the total well leakage, the leakage volume accounts for >85%, the loss time accounts for >30%, and the economic loss caused thereby is as high as more than 50%, which is considered as a "neck-stifling" technical problem in current drilling engineering that needs to be solved urgently and has not been effectively solved.

[0003] In the Sichuan-Chongqing region of China, for example, medium fractures and fracture-caves are widely developed, the leakage channel is large, and the connectivity is good, so that malignant leakage is extremely easy to occur, which seriously threatens the life safety of on-site operators and affects the oil and gas exploration and development process. These large-scale fracture and cave type leakage has a large leakage channel and contains underground water, so that the leak stoppage slurry is easily diluted, washed and lost by the underground water in the leakage layer, and the conventional leak stoppage material is difficult to effectively stay and form a firm sealing layer, so that the leak stoppage success rate is low, the drilling risk is large, and the cost is high.

[0004] It is a technical problem faced by solving the fracture-cave type malignant leakage to develop a leak stoppage material with strong retention capability, high filling and plugging degree and water dilution resistance, so that the leak stoppage slurry can "flow in, stay, fill and resist" in the fracture-cave.

[0005] In recent years, domestic and foreign scholars have designed and developed various malignant leakage leak stoppage technologies, mainly focusing on the research on modified cement and polymer gel. For example, shear thickening liquid leak stoppage technology, diesel-oil-bentonite-cement leak stoppage technology, diesel-oil-bentonite slurry technology, downhole mixing thickening method of sealing agent, thixotropic cement technology, bag type leak stoppage technology, delayed crosslinking polymer, water-swelling and water-thickening type leak stoppage material, etc. Various leak stoppage technologies have certain construction effects, but it is still difficult to effectively solve the problem of malignant leakage.

[0006] Cement, as a typical solidification material, has high pressure-bearing capacity of the sealing body formed thereby, and can produce high-strength sealing for large fracture and cave leakage. Cement slurry is used more in the field of malignant leakage leak stoppage. However, the cement slurry solidification leak stoppage material has high strength but low cohesion, is diluted by water in the formation, has poor retention, and the slurry body will flow into the deep formation along the hole or large pore during the process of squeezing and waiting for setting after shutting down, so that the retention amount near the wellbore is small, and the interfacial cementing strength is unstable, which affects the sealing effect. In addition, the solidification time is not easy to control in a high-temperature and high-calcium environment, and the solidification leak stoppage is more likely to fail in the presence of high salinity water. In addition, the solidification time of cement is difficult to control.

[0007] The gel plugging material is not eroded by water, has strong retention, can be deformed under pressure, can adapt to different size leakage channels without being limited by their morphology, forms a gel plug in the formation that can completely isolate the formation from the wellbore fluid, and can achieve overall plugging of the malignant leakage channel. However, the main defect of the gel is low temperature resistance and low bearing strength, and in a high temperature, high salinity, especially high calcium formation water environment, the plugging slurry performance decreases sharply due to the decrease in viscosity. Another fatal defect is that the density is lower than water, especially after shearing and stirring to form a large amount of bubbles, which reduces the density of the plugging slurry, so that the gel floats on the water surface. When the underground water is not active, it can resist dilution and retention, but when the underground water is active, the gel is easily washed away by water, losing the retention plugging effect; and the remaining gel will continue to absorb water and swell, causing the cohesive force of the gel molecular chain to decrease continuously, thereby losing the plugging effect.

[0008] Therefore, at present, for large fracture-fracture-cave type leakage, a gel+cement technology is used to combine the advantages of both.

[0009] One is to use a double liquid method, first inject a gel thick plug to resist dilution, and then inject cement to set and improve the compressive strength. The double liquid method construction causes the uphole plugging procedure to be complicated, and when the underground water is not active, it can resist dilution, but when the underground water is active, the gel is not easy to retain in a flowing water environment due to its low density, and it is easily washed away by water, losing the plugging effect.

[0010] Second, the gel is compounded with cement. For example, CN111268953A discloses a gel cement, an associated polymer and a preparation method. The gel cement includes 0.6-2 parts of an associated polymer and 100 parts of cement by weight. The associated polymer is obtained by polymerization reaction of reaction monomers consisting of 10%-50% acrylamide, 10%-20% sodium acrylate, 10%-20% N-vinyl pyrrolidone, 20%-50% 2-acrylamido-2-methylpropane sulfonic acid and 5%-10% hydrophobic monomer. The gel cement has high temperature resistance and can effectively eliminate the high temperature gelation phenomenon. After being prepared into a cement slurry, the slurry structure is strong, and has excellent dilution resistance and retention capacity. However, the high water content gel is sheared by a large amount of inorganic particles, the cohesive force decreases sharply, the retention capacity is improved, but the dilution resistance effect is significantly reduced, and the cement solidification time is greatly prolonged due to the presence of a large amount of gel with good water retention. Moreover, as the gel continuously absorbs water, the cement solidification time of the composite gel cement is difficult to control, so that the plugging effect of high bearing pressure, strong dilution resistance and strong retention cannot be achieved. SUMMARY

[0011] In order to overcome the problems that the plugging material is difficult to effectively stay in the large size crack and multi-scale cave type lost circulation formation, the plugging material is easily eroded in the flowing water environment, and the pressure bearing capacity is low, the present application provides a pressure bearing plugging material with anti-dilution and strong retention, taking the water-shearing thickening gel with anti-dilution as the core, cooperating with the strong retention resin and the elastic material, and compounding different particle sizes of particles and fibers to form a pressure bearing plugging agent suitable for the large crack or crack-cave in the active underground water, so as to achieve the plugging effect, and the plugging agent is easy to prepare and pump, and does not need to adjust the setting or crosslinking time.

[0012] Therefore, in a first aspect, the present application provides an anti-dilution and strong retention pressure bearing plugging material, which comprises the following raw materials in mass parts:

[0013] 100 parts of water, 0.5-2.0 parts of water-sensitive shear thickening plugging agent, 5-10 parts of mineral particles, 5-20 parts of composite fibers, and 1-5 parts of retention material.

[0014] As a specific embodiment of the present application, preferably, the water-sensitive shear thickening plugging agent comprises the following raw materials in mass parts:

[0015] 100-200 parts of solvent oil, 10-20 parts of hydrophobic monomer, 40-60 parts of hydrophilic monomer, 10-30 parts of emulsifier, and 0.02-0.1 parts of initiator; preferably, 100-200 parts of solvent oil, 10-20 parts of hydrophobic monomer, 40-60 parts of hydrophilic monomer, 20-30 parts of emulsifier, and 0.04-0.1 parts of initiator;

[0016] Preferably, the solvent oil is selected from at least one of white oil and kerosene; and / or the hydrophobic monomer is selected from at least one of alkyl allyl ammonium chloride and substituted or unsubstituted alkyl acrylate; and / or the hydrophilic monomer comprises acrylamide, acrylic acid and 2-acrylamide-2-methylpropanesulfonic acid, preferably the molar ratio of acrylamide, acrylic acid and 2-acrylamide-2-methylpropanesulfonic acid is 0.8-2:0.5-2:0.6-2, more preferably 0.8-1.2:0.5-1:0.6-1.5; and / or the emulsifier is selected from at least one of sorbitan monooleate, polyoxyethylene octyl phenol ether-10 and polysorbate-80; and / or the initiator comprises redox initiator and thermal decomposition initiator.

[0017] As a specific embodiment of the present application, preferably, the water-sensitive shear thickening plugging agent provided by the present application further comprises the following raw materials in mass parts: 100-300 parts of water, preferably 160-200 parts or 100-150 parts.

[0018] As a specific embodiment of the present application, preferably, the substituted alkyl acrylate (substituted hydrogen on the olefin) contains at least one substituent, preferably the substituent is methyl, preferably the hydrophobic monomer is selected from at least one of octadecyl acrylate, octadecyl methacrylate, alkyl allyl ammonium chloride, alkyl dimethyl allyl ammonium chloride.

[0019] As a specific embodiment of the present application, preferably, the carbon number of the alkyl group in the alkyl acrylate is 10-30, preferably the carbon number is 15-25; the carbon number of the alkyl group in the alkyl allyl ammonium chloride is 10-30, preferably the carbon number is 15-25.

[0020] As a specific embodiment of the present application, preferably, the initiator is composed of a redox initiator and a thermal decomposition initiator; and / or the redox initiator is selected from at least one of ammonium persulfate ((NH4)2S2O8), sodium bisulfite (NaHSO3), potassium persulfate (K2S2O8); and / or the thermal decomposition initiator is selected from at least one of azobisisobutyronitrile (AIBN), azoisobutyrylformamide (V30).

[0021] As a specific embodiment of the present application, preferably, the amount of the emulsifier is 5%-15% of the mass of the solvent oil; and / or the amount of the initiator is 0.01%-0.03% of the mass of the solvent oil; and / or the total mass of the hydrophilic monomer and the hydrophobic monomer is 25%-40% of the mass of the solvent oil; and / or the molar ratio of the hydrophilic monomer to the hydrophobic monomer is 1:(0.01-0.05).

[0022] As a specific embodiment of the present application, preferably, the preparation method of the water-sensitive shear thickening plugging agent comprises the following steps:

[0023] S1: uniformly mix the solvent oil, the hydrophobic monomer, the initiator and the emulsifier to obtain an oil phase;

[0024] S2: prepare a monomer aqueous solution by mixing the hydrophilic monomer with the initiator;

[0025] S3: add the monomer aqueous solution to the oil phase, stir and emulsify to obtain a uniform and stable inverse emulsion system;

[0026] S4: continuously introduce inert gas into the inverse emulsion system, then add the aqueous solution of the initiator to initiate the polymerization reaction; stop adding the aqueous solution of the initiator and stop introducing the inert gas when the temperature of the inverse emulsion system rises to 60-70℃, and continue the heat preservation reaction;

[0027] Optionally, S5: after cooling, add the emulsifier to obtain a stable emulsion polymer;

[0028] Preferably, in step S1, the mass ratio of the solvent oil, the hydrophobic monomer, the initiator and the emulsifier is 1:(0.1-0.2):(0.0001-0.0005):(0.1-0.3); and / or in step S2, the mass ratio of the hydrophilic monomer, the initiator and water is (0.27-0.6):(0.00013-0.001):1; and / or in step S3, the volume ratio of the monomer aqueous solution and the oil phase is 0.5-1:1.

[0029] Preferably, in step S3, the rate of adding the monomer aqueous solution into the oil phase is 5 mL / min-10 mL / min, preferably, the volume of the reaction container for adding the monomer aqueous solution into the oil phase is 500-1000 mL, for example, a three-necked flask with a volume of 500-1000 mL; and / or the stirring rate is 200 rpm-3000 rpm.

[0030] Preferably, in step S4, the inert gas is selected from one of nitrogen N2 and helium He, and / or the flow rate of the inert gas is 50-200 mL / min; and / or the ratio of the mass of the initiator aqueous solution to the mass of the inverse emulsion system is (0.01-0.03):1; and / or the initiator aqueous solution is added after the inert gas is introduced for 0.2-2 hours; and / or the reaction is continued for 2-7 hours.

[0031] Preferably, in step S5, the emulsifier is added after cooling to 30-50℃, and / or the ratio of the amount of the emulsifier to the mass of the inverse emulsion system is (0.05-0.3):1.

[0032] As a specific embodiment of the present application, preferably, the mineral particles include at least one of quartz sand, mica powder, barium sulfate and galena; and / or the mineral particles include three kinds of particles with different particle sizes of 2-4 mm, 0.5-1.5 mm and 30-100 um, and preferably, the mass ratio of the three kinds of particles is 1-5:2-7:5-15.

[0033] As a specific embodiment of the present application, preferably, the composite fiber comprises at least two of walnut shell, cottonseed shell, plastic fiber, preferably at least one of polyester fiber, polypropylene fiber and polylactic acid fiber; and / or the composite fiber comprises at least three of 1-3 mm cellulose particles, 3-5 mm cellulose particles, 5-8 mm cellulose particles and 0.1*5-0.2*10 mm (for example 0.1*5 refers to fiber width*length, which can also be understood as 0.1 mm in transverse dimension and 5 mm in longitudinal dimension) fiber, preferably the mass ratio of 1-3 mm cellulose particles, 3-5 mm cellulose particles, 5-8 mm cellulose particles and 0.1*5-0.2*10 mm fiber in the composite fiber is 4-10:2-8:1-5:1-2.

[0034] Specifically, the composite fiber comprises at least two of walnut shell, cottonseed shell, plastic fiber, and can also comprise at least two of walnut shell-derived fiber, cottonseed shell-derived fiber and plastic fiber.

[0035] As a specific embodiment of the present application, preferably, the retained material comprises at least one of elastic mesh, alloy wire, shape memory alloy and shape memory polymer;

[0036] Preferably, the elastic mesh comprises at least one of high-elasticity mesh I and high-elasticity mesh II; and / or the alloy wire is irregular alloy wire, preferably with a diameter of 2-3 mm, and / or is preferably S-shaped or U-shaped alloy wire; and / or the shape memory alloy is shape memory alloy type temperature-controlled expansion plugging agent SMA, preferably with a mesh size of 20-40; and / or the shape memory polymer is shape memory polymer type temperature-controlled expansion plugging agent SMP, preferably with a mesh size of 40-80.

[0037] To this end, in a second aspect, the present application further provides a preparation method of the above-mentioned impact-resistant and dilution-resistant strong retained pressure plugging material, comprising the following steps:

[0038] (1) preparing a retained plugging slurry: adding mineral particles into water, performing first stirring, adding composite fiber, performing second stirring, adding retained material, performing third stirring to uniformly stir the mixture;

[0039] (2) preparing an impact-resistant and dilution-resistant strong retained plugging slurry: adding water-sensitive shear thickening plugging agent into the retained plugging slurry, and stirring to obtain the impact-resistant and dilution-resistant strong retained pressure plugging material;

[0040] Preferably, in step (1), the stirring speed is 300-500 rpm and the stirring time is 1-3 min; and / or the stirring speed of the second stirring is 300-500 rpm and the stirring time is 5-10 min; and / or the stirring speed of the third stirring is 300-500 rpm and the stirring time is 5-10 min.

[0041] Preferably, in step (2), the stirring condition is: rotation speed 100-300 rpm, stirring time 30 s-120 s.

[0042] For this purpose, in a third aspect, the present application also provides the use of the anti-impact, dilution, strong retention and pressure-bearing plugging material described above or prepared by the preparation method described above in a fracture-vug type lost circulation formation, characterized in that the fracture-vug type lost circulation formation is a malignant lost circulation formation, and preferably, the fracture-vug type lost circulation formation includes a large-pore formation, a fractured formation, a vuggy formation, a large-pore formation with a flowing water environment, a fractured formation with a flowing water environment, and a vuggy formation with a flowing water environment.

[0043] The present application has the following advantages:

[0044] The present application is aimed at the fracture and fracture-vug type lost circulation in an active underground water, uses a water-sensitive plugging material with "water-thickening" and "shear-thickening" as an anti-impact and dilution core treatment agent, uses an elastic pore network material as a retention core treatment agent, and uses a small-particle shape memory material to expand at the well bottom after temperature excitation, which is captured by the elastic pore network and further improves the retention performance of the plugging material in cooperation with a water-sensitive shear-thickening agent with good interfacial viscosity.

[0045] 1. Anti-impact, dilution and strong retention: the plugging material of the present application has a rapid increase in its own viscosity and a significant increase in its consistency under the action of shear after being contacted with water, with a high viscosity of up to 247021 mPa.s, and the gel bridge slurry system formed after thickening has a stable phase interface and is not easy to mix with free-flowing water, so that water is difficult to dilute it, has high elasticity and high viscosity, and has strong adhesion resistance with the rock wall surface, so that it can form effective filling and strong retention in the formation, with a retention capacity of 12.4 MPa / 10 m and an anti-impact dilution degree as low as 2.2%.

[0046] 2. After being contacted with high-temperature and high-salinity formation water in the well, the hydroxyl groups and other active groups in the molecules further undergo multi-stage stereoscopic crosslinking reactions under the action of Ca 2+ , Mg 2+ ions, so that the gel strength is improved and the gel strength and retention capacity are improved.

[0047] 3. Although the plugging material is very thick at the well bottom, the viscosity of the plugging system is similar to that of free water before the water-sensitive shear-thickening agent is added, which is beneficial to preparation and pumping; during the process of going down to the well bottom in the well bore, the viscosity of the water-sensitive shear-thickening agent is significantly increased after being contacted with water and being continuously sheared, which is beneficial to retention, filling of fractures or vugs, and isolation of underground water at the well bottom.

[0048] 4. The lost circulation material not only does not dilute under flowing water conditions, but also stops and stays firmly, and effectively plugs the leakage, and improves the sealing and pressure-bearing capacity of the anti-dilution plugging material, reduces the leakage amount; has good temperature resistance, the temperature resistance reaches 150℃ and above, and the leakage amount is only 2mL when the pressure is 13.5MPa. Not only can effectively solve the low-temperature shallow well fracture-vug type leakage, but also can effectively solve the high-temperature deep well fracture leakage formation, greatly reduce the leakage cost, and improve the economic and social benefits of plugging. DETAILED DESCRIPTION

[0049] The application will be further described below in combination with examples, but does not limit the application. The raw materials used are widely available and can be produced industrially.

[0050] Polyester fiber, 1-5mm, from Taian Hongton New Material Co., Ltd.;

[0051] Polylactic acid fiber, 1-3mm, Shenzhen Guanghua Weiye Co., Ltd.;

[0052] High-elasticity pore network plugging agent, type I, from Drilling Fluid Technology Service Center of Shengli Petroleum Engineering Corporation of Sinopec;

[0053] High-elasticity pore network plugging agent, type II, from Drilling Fluid Technology Service Center of Shengli Petroleum Engineering Corporation of Sinopec;

[0054] Shape memory alloy temperature control expansion plugging agent, SMA, from Example 2 of the patent "Memory Alloy Temperature Control Rigid Expansion Plugging Agent and Preparation Method thereof" (Application No. 201911398781.3);

[0055] Irregular alloy wire, S type (2-3mm), from zinc-aluminum alloy wire annealed wire, Jinzhou City Jingteng Wire Drawing Factory;

[0056] Polyacrylamide, molecular weight 800, composite material factory of Shenghua Industry Co., Ltd. of Shengli Oilfield;

[0057] Water-sensitive shear thickening plugging agent can be prepared by the following synthesis method:

[0058] S1: In a three-necked flask equipped with a thermometer, a mechanical stirrer and a nitrogen inlet tube, add white oil 200g, methyl acrylate 12g, azobisisobutyronitrile 0.01g, sorbitol anhydride monooctadecyl ester (Span-80) 5g and polyoxyethylene octyl phenol ether-10 (OP-10) 5g, stir at 2000rpm to disperse uniformly, and heat to 140℃ to obtain an oil phase;

[0059] S2: Take acrylamide, acrylic acid and 2-acrylamide-2-methylpropanesulfonic acid (AMPS) 50 g in a molar ratio of 1:1:1, and 0.01 g ammonium persulfate ((NH4)2S2O8) to prepare a monomer aqueous solution;

[0060] S3: Slowly add the monomer aqueous solution to the oil phase cooled to room temperature, stir at a speed of 500 rpm, and emulsify for 40 min to obtain a uniform and stable inverse emulsion system;

[0061] S4: Continuously pass N2 into the inverse emulsion system, and after 40 min, slowly add 0.01 g of sodium bisulfite (NaHSO3) aqueous solution to initiate the polymerization reaction; stop adding when the reaction system temperature rises to 70℃, and continue to incubate for 4 h.

[0062] S5: After cooling to room temperature, add 2.5 g of sorbitan monooleate (Span-80) and 2.5 g of polyoxyethylene octylphenol ether-10 (OP-10) to obtain a stable emulsion polymer.

[0063] Example 1

[0064] The anti-impact and strong-retention pressure-bearing plugging material suitable for slot-hole leakage provided in this example is prepared by the following synthesis method:

[0065] S1: Composite fiber preparation: Take walnut shells (1-3 mm), cotton seed shells (5-8 mm) and polyester fibers (0.1*5 mm) 10 g in a mass ratio of 5:2:1, put them into a mixer and mix uniformly to obtain composite fibers;

[0066] S2: Retention plugging slurry preparation: Take 100 mL of water, and add quartz (2-4 mm), mica (0.5-2 mm) and barium sulfate (30-100 um) 5 g one by one according to a mass ratio of 3:3:10, stir at 300 rpm for 2 min, then add the composite fibers, stir at the same speed for 6 min, then add high-elasticity pore network plugging agent type I 1 g, and stir at the same speed for 8 min until uniform, to obtain a retention plugging slurry;

[0067] S3: Anti-impact and strong-retention plugging slurry preparation: Add water-sensitive shear thickening plugging agent 0.8 g to the retention plugging slurry, and stir at 200 rpm for 45 s to obtain an anti-impact and strong-retention pressure-bearing plugging material.

[0068] Example 2

[0069] The anti-impact and strong-retention pressure-bearing plugging material suitable for slot-hole leakage provided in this example is prepared according to the preparation steps of Example 1, except that different amounts of retention materials are added in S2 step. The specific preparation details of S2 step are as follows:

[0070] S2: Retention plugging slurry preparation: take 100 mL of water, add quartz (2-4 mm), mica (0.5-2 mm) and barium sulfate (30-100 um) in the order of 3:3:10 mass ratio, a total of 5 g, 300 rpm stirring for 2 min, then add S1, stirring at the same speed for 6 min, then add 2 g of high-elasticity pore network plugging agent type II for drilling fluid, stirring at the same speed for 8 min until uniform stirring, to obtain the retention plugging slurry.

[0071] Example 3

[0072] The anti-impact and strong dilution retention pressure-bearing plugging material suitable for fracture-vug type leakage provided in this embodiment is prepared by the following synthesis method:

[0073] S2: Retention plugging slurry preparation: take 100 mL of water, add quartz (2-4 mm), mica (0.5-2 mm) and barium sulfate (30-100 um) in the order of 3:3:10 mass ratio, a total of 5 g, 300 rpm stirring for 2 min, then add S1, stirring at the same speed for 6 min, then add 2 g of high-elasticity pore network plugging agent type II for drilling fluid, stirring at the same speed for 8 min until uniform stirring, to obtain the retention plugging slurry.

[0074] Example 4

[0075] The anti-impact and strong dilution retention pressure-bearing plugging material suitable for fracture-vug type leakage provided in this embodiment is prepared by the following synthesis method:

[0076] S1: Composite fiber preparation: take walnut shell (1-3 mm), walnut shell (3-5 mm), cotton seed shell (5-8 mm) and polylactic acid fiber (0.2*10 mm) in the order of 5:3:2:1 mass ratio, a total of 15 g, put into a mixer and mix uniformly to obtain the composite fiber;

[0077] S2: Retention plugging slurry preparation: take 100 mL of water, add quartz (2-4 mm), mica (0.5-2 mm) and barium sulfate (30-100 um) in the order of 3:3:10 mass ratio, a total of 5 g, 300 rpm stirring for 2 min, then add S1, stirring at the same speed for 6 min, then add 2 g of high-elasticity pore network plugging agent type II for drilling fluid, stirring at the same speed for 8 min until uniform stirring, to obtain the retention plugging slurry.

[0078] S3: Anti-impact and strong dilution retention plugging slurry preparation: add water-sensitive shear thickening plugging agent 1.2 g to the retention plugging slurry, stir at 200 rpm for 60 s to obtain the anti-impact and strong dilution retention pressure-bearing plugging material.

[0079] Example 5

[0080] The anti-dilution strong retention pressure-bearing plugging material suitable for fracture-vug type leakage provided by the embodiment is prepared by the following synthesis method:

[0081] S2: Retention plugging slurry preparation: take 100 mL of water, add quartz (2-4 mm), mica (0.5-2 mm) and galena (30-100 um) in a mass ratio of 3:3:10, a total of 8 g, 400 rpm stirring for 2 min, then add S1, stirring at the same speed for 6 min, then add high-elasticity pore network plugging agent type II 1 g and S-shaped irregular alloy wire (2-3 mm) 1 g, stirring at the same speed for 10 min until uniform stirring, to obtain the retention plugging slurry.

[0082] Example 6

[0083] The anti-dilution strong retention pressure-bearing plugging material suitable for fracture-vug type leakage provided by the embodiment is prepared by the following synthesis method:

[0084] S2: Retention plugging slurry preparation: take 100 mL of water, add quartz (2-4 mm), mica (0.5-2 mm) and galena (30-100 um) in a mass ratio of 3:3:10, a total of 8 g, 400 rpm stirring for 2 min, then add S1, stirring at the same speed for 6 min, then add high-elasticity pore network plugging agent type II 1 g and S-shaped irregular alloy wire (2-3 mm) 1 g, stirring at the same speed for 10 min until uniform stirring, to obtain the retention plugging slurry.

[0085] Example 7

[0086] The anti-dilution strong retention pressure-bearing plugging material suitable for fracture-vug type leakage provided by the embodiment is prepared by the following synthesis method:

[0087] S1: Composite fiber preparation: take walnut shell (1-3 mm), walnut shell (3-5 mm), cotton seed shell (5-8 mm) and polypropylene fiber (0.2*10 mm) in a mass ratio of 5:3:2:1, a total of 20 g, put into a mixer and mix uniformly to obtain the composite fiber;

[0088] S2: Retention plugging slurry preparation: take 100 mL of water, add quartz (2-4 mm), mica (0.5-2 mm) and galena (30-100 um) in a mass ratio of 3:3:10, a total of 8 g, 400 rpm stirring for 2 min, then add S1, stirring at the same speed for 6 min, then add high-elasticity pore network plugging agent type II 1 g and S-shaped irregular alloy wire (2-3 mm) 1 g, stirring at the same speed for 10 min until uniform stirring, to obtain the retention plugging slurry;

[0089] S3: Anti-impact and dilution strong retention and pressure-bearing plugging slurry preparation: add water-sensitive shear thickening plugging agent 1.5 g to the retention and pressure-bearing plugging slurry, stir at 300 rpm for 60 s, and obtain the anti-impact and dilution strong retention and pressure-bearing plugging material.

[0090] Example 8

[0091] The anti-impact and dilution strong retention and pressure-bearing plugging material provided in this example is suitable for fracture and hole type loss. The preparation steps are as in Example 7, except that different retention materials are added in the S2 step. The specific preparation details of the S2 step are as follows:

[0092] S2: Retention and pressure-bearing plugging slurry preparation: take 100 mL of water, and add quartz (2-4 mm), mica (0.5-2 mm), and galena (30-100 um) in a mass ratio of 3:3:10, a total of 8 g. Stir at 400 rpm for 3 min, then add composite fibers, and stir at the same speed for 6 min. Then add high-elasticity pore network plugging agent type II 1 g, shape memory polymer type temperature-controlled expansion plugging agent SMP (40-80 mesh) 2 g, and stir at the same speed for 8 min until uniform, to obtain the retention and pressure-bearing plugging slurry.

[0093] Example 9

[0094] The anti-impact and dilution strong retention and pressure-bearing plugging material provided in this example is suitable for fracture and hole type loss. The preparation steps are as in Example 7, except that different retention materials are added in the S2 step. The specific preparation details of the S2 step are as follows:

[0095] S2: Retention and pressure-bearing plugging slurry preparation: take 100 mL of water, and add quartz (2-4 mm), mica (0.5-2 mm), and galena (30-100 um) in a mass ratio of 3:3:10, a total of 8 g. Stir at 400 rpm for 3 min, then add composite fibers, and stir at the same speed for 6 min. Then add high-elasticity pore network plugging agent type II 1 g, shape memory polymer type temperature-controlled expansion plugging agent SMP (40-80 mesh) 2 g, and shape memory alloy type temperature-controlled expansion plugging agent SMA (20-40 mesh) 1 g, and stir at the same speed for 8 min until uniform, to obtain the retention and pressure-bearing plugging slurry.

[0096] Comparative Example 1

[0097] The anti-impact and dilution strong retention and pressure-bearing plugging material provided in this example is suitable for fracture and hole type loss. The preparation steps are as in Example 9, except that no water-sensitive shear thickening plugging agent is added in the S3 step. The specific preparation steps are as follows:

[0098] S1: Composite fiber preparation: take walnut shell (1-3 mm), walnut shell (3-5 mm), cotton seed shell (5-8 mm), and polypropylene fiber (0.2*10 mm) in a mass ratio of 5:3:2:1, a total of 20 g, and mix in a mixer until uniform, to obtain the composite fiber.

[0099] S2: Retention plugging slurry preparation: take 100 mL of water, add quartz (2-4 mm), mica (0.5-2 mm) and galena (30-100 um) 8 g one by one according to the mass ratio of 3:3:10, stir at 400 rpm for 3 min, then add composite fiber, stir at the same speed for 6 min, then add high-elasticity pore network plugging agent type II 1 g, shape memory polymer type temperature control swelling plugging agent SMP (40-80 mesh) 2 g and shape memory alloy type temperature control swelling plugging agent SMA (20-40 mesh) 1 g, stir at the same speed for 8 min until uniform, get retention plugging slurry, that is, the final product.

[0100] Comparative Example 2

[0101] The anti-impact and strong retention pressure-bearing plugging material suitable for slot-hole type leakage provided by this comparative example has the same preparation steps as Example 9, except that no mineral particles are added in S2. The specific preparation steps are as follows:

[0102] S1: Composite fiber preparation: take walnut shell (1-3 mm), walnut shell (3-5 mm), cotton seed shell (5-8 mm) and polypropylene fiber (0.2*10 mm) 20 g according to the mass ratio of 5:3:2:1, put into the mixer and mix uniformly, get the composite fiber;

[0103] S2: Retention plugging slurry preparation: take 100 mL of water, add composite fiber to it, stir at 400 rpm for 3 min, then add high-elasticity pore network plugging agent type II 1 g, shape memory polymer type temperature control swelling plugging agent SMP (40-80 mesh) 2 g and shape memory alloy type temperature control swelling plugging agent SMA (20-40 mesh) 1 g, stir at the same speed for 8 min until uniform, get retention plugging slurry;

[0104] S3: Anti-impact and strong retention plugging slurry preparation: add water-sensitive shear thickening plugging agent 1.5 g to the retention plugging slurry, stir at 300 rpm for 60 s, get the anti-impact and strong retention pressure-bearing plugging material.

[0105] Comparative Example 3

[0106] The anti-impact and strong retention pressure-bearing plugging material suitable for slot-hole type leakage provided by this comparative example has the same preparation steps as Example 9, except that no composite fiber is added. The specific preparation steps are as follows:

[0107] S1: Retention plugging slurry preparation: take 100 mL of water, add quartz (2-4 mm), mica (0.5-2 mm) and galena (30-100 um) in the order of 8 g according to the mass ratio of 3:3:10, stir at 400 rpm for 3 min, then add high-elasticity pore screen plugging agent type II 1 g, shape memory polymer type temperature control swelling plugging agent SMP (40-80 mesh) 2 g and shape memory alloy type temperature control swelling plugging agent SMA (20-40 mesh) 1 g, stir at the same speed for 8 min until uniform, to obtain the mixture retention plugging slurry;

[0108] S2: Anti-impact and strong dilution retention plugging slurry preparation: add water-sensitive shear thickening plugging agent 1.5 g to the retention plugging slurry, stir at 300 rpm for 60 s to obtain the anti-impact and strong dilution retention and pressure-bearing plugging material.

[0109] Comparative Example 4

[0110] The anti-impact and strong dilution retention and pressure-bearing plugging material provided by the present comparative example is suitable for slot-hole type loss, and the preparation steps are as follows:

[0111] S1: Composite fiber preparation: take walnut shell (1-3 mm), walnut shell (3-5 mm), cotton seed shell (5-8 mm) and polypropylene fiber (0.2*10 mm) in the order of 20 g according to the mass ratio of 5:3:2:1, put into a mixer and mix uniformly to obtain the composite fiber.

[0112] S2: Retention plugging slurry preparation: take 100 mL of water, add quartz (2-4 mm), mica (0.5-2 mm) and galena (30-100 um) in the order of 8 g according to the mass ratio of 3:3:10, stir at 400 rpm for 3 min, then add S1, stir at the same speed for 6 min until uniform to obtain the retention plugging slurry.

[0113] S3: Anti-impact and strong dilution retention plugging slurry preparation: add water-sensitive shear thickening plugging agent 1.5 g to the retention plugging slurry, stir at 300 rpm for 60 s to obtain the anti-impact and strong dilution retention and pressure-bearing plugging material.

[0114] Comparative Example 5

[0115] The anti-impact and strong dilution retention and pressure-bearing plugging material provided by the present comparative example is suitable for slot-hole type loss, and the preparation steps are as follows:

[0116] S1: composite fiber preparation: walnut shell (1-3 mm), walnut shell (3-5 mm), cotton seed shell (5-8 mm) and polypropylene fiber (0.2*10 mm) are weighed according to the mass ratio of 5:3:2:1, a total of 20 g, and put into a mixer to mix evenly, to obtain a composite fiber;

[0117] S2: retention and plugging slurry preparation: 100 mL of water is measured, and quartz (2-4 mm), mica (0.5-2 mm) and galena (30-100 um) are added one by one according to the mass ratio of 3:3:10, a total of 8 g, 400 rpm stirring for 3 min, then adding composite fiber, stirring at the same speed for 6 min, then adding high-elasticity mesh plugging agent type II 1 g, shape memory polymer type temperature control expansion plugging agent SMP (40-80 mesh) 2 g and shape memory alloy type temperature control expansion plugging agent SMA (20-40 mesh) 1 g, stirring at the same speed for 8 min until stirring is uniform, to obtain a retention and plugging slurry, which is the final product.

[0118] S3: preparation of anti-impact and strong dilution retention and plugging slurry: polyacrylamide 1.5 g is added to the retention and plugging slurry, and stirred at 300 rpm for 60-120 min to obtain an anti-impact and strong dilution retention and pressure-bearing plugging material.

[0119] Test Example 1: water-thickening performance test

[0120] The viscosity of Examples 1-9 and Comparative Examples 1-5 was measured at 3 r / min using a DV-III Brookfield viscometer and recorded, and the results are shown in Table 1 below.

[0121] Table 1: Water-thickening performance of examples and comparative examples

[0122] Tested slurry Viscosity / mPa.s Example 1 101470 Example 2 101285 Example 3 101173 Example 4 200355 Example 5 200355 Example 6 201487 Example 7 246953 Example 8 247003 Example 9 247021 Comparative Example 1 126 Comparative Example 2 246953 Comparative Example 3 247260 Comparative Example 4 247286 Comparative Example 5 1730

[0123] As can be seen from Table 1, although the viscosity of Comparative Examples 2-4 is higher due to the addition of more water-sensitive shear-thickening plugging agents, the loss amount of Comparative Examples 2-4 is significantly higher than that of Examples 1-9, and the pressure-bearing capacity and retention performance of Examples 4-9 are better than those of Comparative Examples 2-4, while the plugging components of Examples 1-3 are lower than those of Comparative Examples 2-4, and the pressure-bearing capacity is comparable. Therefore, it can be seen that the anti-impact and strong dilution retention and pressure-bearing plugging material provided by the examples has the best comprehensive performance.

[0124] Test Example 2: Anti-impact and dilution retention performance

[0125] This test uses a plugging material anti-impact and dilution retention performance testing device to test the anti-impact and dilution retention performance of Examples 1-9 and Comparative Examples 1-5, and the specific test steps are as follows.

[0126] The steel pipe is filled with the slurry to be tested, recorded as m0; the temperature is raised to 80 DEG C for 15 min to complete gelation, the steel pipe is connected with a nitrogen bottle, and slow pressurization is carried out, the driving pressure of the tested plugging liquid is observed, the driving pressure of a 10 m long slug is converted according to the length of the slug, that is, the retention capacity, the greater the driving pressure, the stronger the retention. The plugging liquid is continuously driven until it passes through a 200 mesh sieve, the free water is filtered out, and then the residual plugging agent is weighed as m1, then the impact resistance release degree = 100 (m1-m0) / m0, the greater the value, the lower the impact resistance release degree. The obtained test data are shown in Table 2.

[0127] Table 2 impact resistance and retention performance of examples and comparative examples

[0128]

[0129] As shown in Table 2, the plugging material has good impact resistance and retention performance, the retention capacity can be up to 12.4 MPa / 10 m, and the impact resistance can be as low as 2.2%.

[0130] Test example 3: plugging pressure bearing performance

[0131] The test uses a drilling fluid dynamic filtration and long fracture plugging simulation experimental device to test the plugging effect of examples 1 to 9 and comparative examples 1 to 4 on a 5*4 mm slit plate fracture, wherein the test temperature of examples 3, 6, 8 and 9 is 150 DEG C, and the test temperature of other examples and comparative examples is 80 DEG C, the pressure bearing and cumulative leakage are recorded, and the results are shown in Table 3.

[0132] Table 3 plugging pressure bearing performance of examples and comparative examples

[0133]

[0134] The plugging material has good plugging pressure bearing capacity for the fracture, the pressure resistance can be up to 13.5 MPa, and the cumulative leakage can be less than 2 mL, and the plugging effect of the example prepared by low concentration of the water-sensitive shear thickening plugging agent is obviously better than that of the comparative example prepared by high concentration.

[0135] The application is aimed at the active fracture and fracture-cave type leakage of underground water, and uses the water-sensitive plugging material with water-thickening and shear thickening as the impact resistance and dilution core treatment agent, uses the elastic pore network material as the retention core treatment agent, and the small particle shape memory material is expanded by temperature excitation at the well bottom, is captured by the elastic pore network, and cooperates with the water-sensitive shear thickening agent with good interfacial viscosity to further improve the retention performance of the plugging material; meanwhile, the composite mineral particles and fibers with different particle sizes and the water-sensitive shear thickening agent with high elastic gel structure establish a multi-dimensional plugging system to enhance the plugging effect and pressure bearing capacity. The characteristic advantages and performance indexes are as follows:

[0136] 1. Anti-dilution and strong retention: the plugging material of the present application has a rapid increase in viscosity and a significant increase in consistency under shear after being contacted with water, up to 247021 mPa.s, and the gel bridge slurry system formed after thickening has a stable phase interface and is not easily mixed with free flowing water phase, and is difficult to be diluted by water, has high elasticity and high viscosity, and strong viscous resistance with the rock wall surface, can form effective filling and strong retention in the formation, the retention capacity reaches 12.4 MPa / 10 m, and the anti-dilution degree can be as low as 2.2%.

[0137] 2. After being contacted with high temperature and high salinity formation water downhole, the hydroxyl groups in the molecules are further subjected to multi-stage stereoscopic crosslinking reactions under the action of Ca 2+ , Mg 2+ ions, and the gel strength is increased by improving the molecular aggregation state.

[0138] 3. Although the plugging material is very thick at the well bottom, the viscosity of the plugging system is similar to that of free water before the addition of the water-sensitive shear thickening agent, which is beneficial to preparation and pumping; during the process of going down to the well bottom, the viscosity of the water-sensitive shear thickening agent is significantly increased only after being continuously sheared after being contacted with water, which is beneficial to retention, filling of cracks or fracture-cavity, and isolation of underground water at the well bottom.

[0139] 4. The plugging material not only is not diluted under flowing water conditions, but also is stopped, firmly retained, and effectively plugged, and the plugging pressure-bearing capacity of the anti-dilution plugging material is improved and the leakage amount is reduced; the temperature resistance is good, and the leakage amount is only 2 mL when the pressure is 13.5 MPa at a temperature resistance of 150℃ or above. Not only can it effectively solve the fracture-cavity type leakage in low temperature shallow wells, but also can effectively solve the crack leakage in high temperature deep wells, greatly reduce the leakage cost, and improve the economic and social benefits of plugging.

[0140] The above description of the embodiments is for the purpose of facilitating understanding and application of the present application by those of ordinary skill in the art. Those skilled in the art can easily make various modifications to the embodiments, and apply the general principles described herein to other embodiments without creative labor. Therefore, the present application is not limited to the embodiments herein, and improvements and modifications made by those skilled in the art without departing from the scope of the present application should be within the scope of protection of the present application. For example, the addition of other functional additives in the preparation of the components of the present application also falls within the scope of protection of the present application.

Claims

1. A shock resistant, dilution resistant, high retention, pressure containing, plugging material, characterized in that, According to the quality parts, including the following raw materials: Water 100 parts, water-sensitive shear thickening plugging agent 0.5-2.0 parts, mineral particles 5-10 parts, composite fibers 5-20 parts, retention material 1-5 parts; The water-sensitive shear thickening plugging agent includes the following raw materials: Solvent oil 100-200 parts, hydrophobic monomer 10-20 parts, hydrophilic monomer 40-60 parts, emulsifier 10-30 parts, initiator 0.02-0.1 parts; The hydrophobic monomer is selected from at least one of alkyl allyl ammonium chloride, substituted or unsubstituted alkyl acrylate; The hydrophilic monomer includes acrylamide, acrylic acid and 2-acrylamide-2-methylpropane sulfonic acid; The composite fiber includes walnut shell, cottonseed hull, plastic fiber, and the plastic fiber includes at least one of polyester fiber, polypropylene fiber and polylactic acid fiber; The retention material includes elastic mesh, and optionally, the retention material further includes at least one of alloy wire, shape memory alloy and shape memory polymer.

2. The lost circulation material of claim 1, wherein, According to the quality parts, the water-sensitive shear thickening plugging agent includes the following raw materials: Solvent oil 100-200 parts, hydrophobic monomer 10-20 parts, hydrophilic monomer 40-60 parts, emulsifier 20-30 parts, initiator 0.04-0.1 parts.

3. The lost circulation material of claim 2, wherein, The solvent oil is selected from at least one of white oil and kerosene; and / or the emulsifier is selected from at least one of sorbitan monooleate, polyoxyethylene octyl phenol ether-10 and polysorbate-80; and / or the initiator includes redox initiator and thermal decomposition initiator.

4. The lost circulation material of claim 3, wherein, The molar ratio of acrylamide, acrylic acid and 2-acrylamide-2-methylpropane sulfonic acid in the hydrophilic monomer is 0.8-2:0.5-2:0.6-2.

5. The lost circulation material of claim 4, wherein, The molar ratio of acrylamide, acrylic acid and 2-acrylamide-2-methylpropane sulfonic acid in the hydrophilic monomer is 0.8-1.2:0.5-1:0.6-1.

5.

6. The lost circulation material of claim 3, wherein, The substituted alkyl acrylate contains at least one substituent.

7. The lost circulation material of claim 6, wherein, The substituent in the substituted alkyl acrylate is methyl.

8. The lost circulation material of claim 7, wherein, The hydrophobic monomer is selected from at least one of octadecyl acrylate, octadecyl methacrylate, alkyl allyl ammonium chloride and alkyl dimethyl allyl ammonium chloride.

9. The lost circulation material of any one of claims 1-8, wherein, The initiator is composed of redox initiator and thermal decomposition initiator; the redox initiator is selected from at least one of ammonium persulfate ((NH4)2S2O8), sodium bisulfite (NaHSO3) and potassium persulfate (K2S2O8); and / or the thermal decomposition initiator is selected from at least one of azobisisobutyronitrile (AIBN) and azoisobutyrylformamide (V30).

10. The lost circulation material of any one of claims 1-8, wherein, The emulsifier is used in an amount of 5%-15% of the mass of the solvent oil; and / or the initiator is used in an amount of 0.01%-0.03% of the mass of the solvent oil; and / or the total mass of the hydrophilic monomer and the hydrophobic monomer is 25%-40% of the mass of the solvent oil; and / or the molar ratio of the hydrophilic monomer to the hydrophobic monomer is 1:(0.01-0.05).

11. The lost circulation material of any one of claims 1-8, wherein, The water-sensitive shear thickening plugging agent preparation method includes the following steps: S1: uniformly mixing solvent oil, hydrophobic monomer, initiator and emulsifier to obtain oil phase; S2: preparing monomer aqueous solution by mixing hydrophilic monomer and initiator; S3: adding monomer aqueous solution into oil phase, stirring and emulsifying to obtain uniform and stable inverse emulsion system; S4: continuously introducing inert gas into inverse emulsion system, then adding water solution of initiator to initiate polymerization reaction; when the temperature of inverse emulsion system rises to 60-70℃, stop adding and stop introducing inert gas, and continue to heat reaction; Optionally, S5: adding emulsifier after cooling to obtain stable emulsion polymer.

12. The lost circulation material of claim 11, wherein, In step S1, the mass ratio of the solvent oil, the hydrophobic monomer, the initiator and the emulsifier is 1: (0.1-0.2): (0.0001-0.0005): (0.1-0.3); and / or in step S2, the mass ratio of the hydrophilic monomer, the initiator and water is (0.27-0.6): (0.00013-0.001): 1; and / or in step S3, the volume ratio of the monomer aqueous solution and the oil phase is 0.5-1: 1; and / or In step S3, the rate of adding the monomer aqueous solution into the oil phase is 5 mL / min-10 mL / min; and / or the stirring rate is 200 rpm-3000 rpm; and / or In step S4, the inert gas is selected from one of nitrogen N2 and helium He, and / or the introduction rate of the inert gas is 50-200 mL / min; and / or the ratio of the mass of the water solution of the initiator to the mass of the inverse emulsion system is (0.01-0.03): 1; and / or the water solution of the initiator is added after introducing the inert gas for 0.2-2 hours; and / or the heat reaction continues for 2-7 hours; and / or In step S5, the emulsifier is added after cooling to 30-50℃, and / or the ratio of the amount of the emulsifier to the mass of the inverse emulsion system is (0.05-0.3):

1.

13. The lost circulation material of any one of claims 1-8, wherein, The mineral particles include at least one of quartz sand, mica powder, barium sulfate and galena; the mineral particles include three kinds of particles with different particle sizes of 2-4 mm, 0.5-1.5 mm and 30-100 um.

14. The lost circulation material of claim 13, wherein, The mass ratio of the three kinds of particles in the mineral particles is 1-5: 2-7: 5-15.

15. The lost circulation material of any one of claims 1-8, wherein, The composite fiber includes at least three of 1-3 mm cellulose particles, 3-5 mm cellulose particles, 5-8 mm cellulose particles and 0.1*5-0.2*10 mm fibers.

16. The lost circulation material of claim 15, wherein, The mass ratio of 1-3 mm cellulose particles, 3-5 mm cellulose particles, 5-8 mm cellulose particles and 0.1*5-0.2*10 mm fibers in the composite fiber is 4-10: 2-8: 1-5: 1-2.

17. The lost circulation material of any one of claims 1-8, wherein, The elastic mesh includes at least one of high-elasticity mesh I and high-elasticity mesh II; and / or the alloy wire is irregular alloy wire; and / or the shape memory alloy is shape memory alloy temperature control expansion plugging agent SMA; and / or the shape memory polymer is shape memory polymer temperature control expansion plugging agent SMP.

18. The lost circulation material of claim 17, wherein, The diameter of the irregular alloy wire is 2-3 mm; and / or the alloy wire is an S-shaped or U-shaped alloy wire; and / or the shape memory alloy is 20-40 mesh; and / or the shape memory polymer is 40-80 mesh.

19. A process for the preparation of the impact-resistant, dilution-resistant, high-retention, pressure-containing, plugging material according to any one of claims 1 to 18, characterized in that The method comprises the following steps: (1) preparing a retention plugging slurry: adding mineral particles into water, stirring for the first time, then adding composite fibers, stirring for the second time, then adding retention materials, stirring for the third time to uniformly stir the mixture; (2) preparing a strong anti-impact and dilution retention plugging slurry: adding a water-sensitive shear thickening plugging agent into the retention plugging slurry, and stirring to obtain a strong anti-impact and dilution retention and pressure-bearing plugging material.

20. The method of claim 19, wherein, In step (1), the first stirring is performed at a speed of 300-500 rpm for 1-3 min; and / or the second stirring is performed at a speed of 300-500 rpm for 5-10 min; and / or the third stirring is performed at a speed of 300-500 rpm for 5-10 min; and / or In step (2), the stirring is performed at a speed of 100-300 rpm for 30 s-120 s.

21. Use of the impact-resistant, dilution-resistant, strong-retention, pressure-containing, plugging material according to any one of claims 1 to 18 or the impact-resistant, dilution-resistant, strong-retention, pressure-containing, plugging material prepared by the preparation method according to claim 19 or 20 in a fracture-vug type lost circulation formation, characterized in that, The fracture-vug type lost circulation formation is a malignant lost circulation formation.

22. The use according to claim 21, characterized in that, The fracture-vug type lost circulation formation includes a large-pore formation, a fractured formation, a vuggy formation, a large-pore formation with a flowing water environment, a fractured formation with a flowing water environment, and a vuggy formation with a flowing water environment.

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