A method for producing a cement leakproof external admixture modified glass fiber

Abstract

The application discloses a production method of cement leakproof external admixture modified glass fiber, and belongs to the technical field of modified glass fiber. The method adopts coupling treatment, active treatment and infiltration treatment, and is used as an inert plugging material for solving the cement slurry leakage problem in cementing operation. The material is easy to disperse in the cement slurry and can quickly form a bridge plug at a fractured leakage formation, thereby preventing further cement slurry leakage to the formation. After the treatment, the cement has good affinity, which is beneficial to increasing the toughness of the cement stone and improving the impact resistance of the cement sheath. The polymeric calcium aluminate powder can play a role in accelerating the cement setting, improve the early strength of the cement stone, and play a synergistic effect with the glass fiber, thereby shortening the cement slurry thickening time. The amino silicone oil emulsion has good alkali resistance and stability, the modified amino silicone oil emulsion in the infiltration liquid can reduce the hydrophilic hydroxyl groups on the surface of the fiber, improve the infiltration property, the fiber has good infiltration property with the matrix, and the EVA emulsion can improve the compactness of the glass fiber blending.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of modified glass fiber, and particularly relates to a production method of cement leakage-proof external admixture modified glass fiber. BACKGROUND

[0002] In order to improve the high-temperature strength recession defect of silicate oil well cement stone, at present, the commonly used method at home and abroad is to select appropriate proportion, particle size and type of quartz sand and other siliceous external admixtures to mix with G-grade oil well cement, to improve the silica-calcium ratio of the cement stone, to form a hydration product with better high-temperature resistance, and to improve the high-temperature resistance of the cement stone. The most common solution is to add silica sand as an external admixture to prevent the strength recession of the oil well cement. Because there are some problems in the use of oil well cement, such as low early strength of the cement stone, high porosity and permeability, etc., it is necessary to use other external admixtures and external admixtures in combination, and the active external admixture is an indispensable material for effectively improving the performance of the oil well cement. Zhao Lian et al. used natural zeolite as an external admixture of oil well cement. Cheng Xiaowei et al. studied the use of rice husk ash as an external admixture of oil well cement, and preliminarily explored the mechanism of rice husk ash in improving the mechanical properties of the cement stone. However, the toughness of the cement stone is poor, and the impact resistance of the cement sheath is not good. The technical personnel in the field are in urgent need of developing a production method of cement leakage-proof external admixture modified glass fiber to meet the existing application market and performance requirements. SUMMARY

[0003] In view of this, the application provides a production method of cement leakage-proof external admixture modified glass fiber.

[0004] A production method of cement leakage-proof external admixture modified glass fiber, comprising the steps of conventional water immersion, dehydration, cutting and drying to obtain short-cut glass fiber, further comprising the following steps: (1) putting the short-cut glass fiber into a kneader, adding 2-3% of a coupling agent by mass to the short-cut glass fiber, and kneading for 5-10 minutes at a temperature of 100-120 DEG C; (2) activation treatment: weighing 12-15 parts of polyaluminum calcium powder, 18-24 parts of polyvinyl alcohol, and 45-64 parts of hot water at 80-90 DEG C, and then mixing the components to obtain an activator; adding 5-10% of the activator by mass to the short-cut glass fiber after step (1), stirring and activating the short-cut glass fiber, and drying at 60-70 DEG C until the weight is constant to obtain activated short-cut glass fiber; (3) infiltration modification: weighing the components according to the following weight ratio: 34-38 parts of amino silicone oil emulsion, 3-5 parts of silane coupling agent, 15-20 parts of EVA emulsion, and 65-75 parts of water, and uniformly mixing to obtain an infiltration liquid; immersing the activated short-cut glass fiber in the infiltration liquid for 30-40 minutes, taking out and drying and solidifying at 65-85 DEG C for 0.5-1 hour to obtain the cement leakage-proof external admixture modified glass fiber.

[0005] Further, the amino silicone oil emulsion of step (3) is a TF-457 amino silicone oil emulsion with a solid content of 4-6% or a SM-17 amino silicone oil emulsion with a solid content of 4-6%.

[0006] Further, the coupling agent is one or more of an aluminum-zirconium coupling agent or an aluminum-titanium composite coupling agent.

[0007] Further, the EVA emulsion of step (3) is an ethylene-vinyl acetate emulsion with a solid content of 2-3%.

[0008] Further, the silane coupling agent of step (3) is one of 3-glycidyloxypropyltrimethoxysilane or gamma-methacryloyloxypropyltrimethoxysilane.

[0009] Further, the chopped glass fiber of step (1) has a diameter of 11-14 μm and a chopped length of 3-15 mm. The cement leak-proof external admixture modified glass fiber production method disclosed in the present application adopts coupling treatment, active treatment, and infiltration treatment to produce inert plugging modified glass fiber that solves the cement slurry leakage problem in cementing water injection operations. The aluminum-zirconium coupling agent or aluminum-titanium coupling agent can form a covalent bond with the surface of the glass fiber through condensation, is easy to disperse in the cement slurry, can quickly form a bridge plug at a fractured leakage formation, and prevents the generation of further cement slurry leakage to the formation. After treatment, the cement has good affinity, which is beneficial to increasing the toughness of the cement stone and improving the impact resistance of the cement sheath. The polymeric calcium aluminate powder can play a role in accelerating the setting of the cement, improve the early strength of the cement stone, and play a synergistic effect with the glass fiber, shorten the cement slurry thickening time, the amino silicone oil emulsion has good alkali resistance, the amino silicone oil emulsion modification in the infiltration liquid can reduce the hydrophilic hydroxyl groups on the surface of the fiber, improve the wettability, the fiber has good wettability with the matrix, and the EVA emulsion can improve the compactness of the glass fiber blending. DETAILED DESCRIPTION Example 1

[0010] Raw materials and equipment: Yongchang Ruitong polymeric calcium aluminate powder, Yangzhou Lida LD139 aluminum-zirconium coupling agent; Dingchuan gantry cutting machine LM-600, cutting knife 580 type; cutting knife purchased from Jingyu mechanical cutter; vibrating screen YAH1548 / YAH1842D2S linear vibrating screen; finished product screen (linear swing screen) linear swing screen 400x800; Riyi fluidized bed drying equipment ZLG7.5x1.2; hot blast stove; Haogu intelligent packaging machine QGD-800K; Henghao mechanical centrifugal dehydrator SS753-600; crane RS485; soaking pool 1.5m x 1.5m x 1.8m. Amino silicone oil emulsion is solid content 6% of transmission TF-457; EVA emulsion is solid content 12% of ethylene-vinyl acetate emulsion DA-102; silane coupling agent is three-fu 3-glycidyl ether oxypropyl trimethoxysilane SF-H560; polyvinyl alcohol GJ-S.

[0011] The production method of cement leak-proof external admixture modified glass fiber comprises the following steps: the medium-fiber alkali-free glass fiber filament is hoisted into the soaking pool by the crane, soaked for 10-15 min, the glass fiber is loaded into the centrifugal dehydrator to dehydrate to 5% water content, the dehydrated glass fiber filament is loaded into the gantry cutting knife for cutting, the cut glass fiber is automatically dropped into the vibrating screen for screening, and then dropped into the fluidized bed dryer for drying, and the dried glass fiber is sent into the finished product screen through the conveying belt for further screening and grading to obtain the chopped glass fiber with a diameter of 11μm and a chopped length of 3mm.

[0012] The production method of cement leak-proof external admixture modified glass fiber further comprises the following steps:

[0013] The first step, the chopped glass fiber is put into the kneader, 3% of the coupling agent by mass is added for kneading treatment, and the temperature is 120℃ and the time is 10 min; the second step, activation treatment: 15 parts of polymeric calcium aluminate powder, 24 parts of polyvinyl alcohol and 64 parts of hot water at 90℃ are weighed according to the weight ratio, and then the components are uniformly mixed to obtain an activator; 10% of the activator by mass is added to the chopped glass fiber after the first step of kneading for stirring and activation treatment, and the temperature is 70℃ and the time is until constant weight, to obtain activated chopped glass fiber; the third step, infiltration modification: the components are weighed according to the following weight ratio: 38 parts of amino silicone oil emulsion, 5 parts of silane coupling agent, 20 parts of EVA emulsion and 75 parts of water, which are uniformly mixed to obtain an infiltration liquid; the activated chopped glass fiber is immersed in the infiltration liquid for 40 min, taken out and dried and solidified at 85℃ for 0.5h, and then packaged by the packaging machine.

[0014] The modified glass fiber product: the final setting time change rate is 95%; the leakage amount is 42mL; the thickening time (52℃, 35.6MPa) is 90min; the initial consistency is 25Bc; the compressive strength (52℃, 24h) is 14.5MPa. Example 2

[0015] Raw materials and equipment: Yongchang Ruitong polyaluminate powder, Yangzhou Lida LD aluminum-titanium coupling agent; Dingchuan gantry electric cutter type 58; cutter purchased from Jingyu Machinery; vibrating screen YAH1548 / YAH1842D2S linear vibrating screen; finished product screen linear swing screen 400×800; Rihong fluidized bed drying equipment ZLG7.5x1.2; hot air furnace; Haopu intelligent packaging machine QGD-800K; Henghao Machinery centrifugal dewatering machine SS753-600; overhead crane RS485; soaking tank 1.5m×1.5m×1.8m. Amino silicone oil emulsion is SM-17 amino silicone oil emulsion with a solid content of 4-6%; EVA emulsion is ethylene-vinyl acetate emulsion CW40-707 with a solid content of 3%; silane coupling agent is Sanfu γ-methacryloyloxypropyltrimethoxysilane SF-X570; polyvinyl alcohol GJ S.

[0016] The production method of modified glass fiber as an admixture for cement leak prevention includes the following steps: medium-density alkali-free glass fiber filaments are immersed in water in a soaking tank by a crane for 10-15 minutes. The glass filaments are then put into a centrifugal dewatering machine to dehydrate to a moisture content of 5%. The dehydrated glass fiber filaments are then cut by a gantry cutter. The cut glass fiber filaments automatically fall into a vibrating screen for sieving. After sieving, they fall into a fluidized bed dryer for drying. After drying, the glass fiber is sent to a finished product screen by a conveyor belt for further sieving and grading to obtain chopped glass fiber with a diameter of 14μm and a chopped length of 15mm.

[0017] Step 1: Place chopped glass fibers in a kneader and add 2% (by weight) of coupling agent for kneading at 100°C for 5 minutes. Step 2: Activation treatment: Weigh 12 parts polyaluminate powder, 18 parts polyvinyl alcohol, and 45 parts hot water (80-90°C) according to the following weight ratios, and mix the components evenly to obtain an activator. Add 5% (by weight) of the activator to the kneaded chopped glass fibers from Step 1 and stir for activation treatment. Dry at 60°C to constant weight to obtain activated chopped glass fibers. Step 3: Impregnation modification: Weigh the following components according to the following weight ratios: 34 parts amino silicone oil emulsion, 3 parts silane coupling agent, 15 parts EVA emulsion, and 65 parts water, and mix evenly to obtain an impregnation solution. Immerse the activated chopped glass fibers in the impregnation solution for 30 minutes, remove, and dry and cure at 65°C for 1 hour to obtain the final product.

[0018] Modified glass fiber products: final setting time change rate 90%; leakage 50mL; thickening time (52℃, 35.6MPa) 95min; initial consistency 20Bc; compressive strength (52℃, 24h) 14.0MPa.

[0019] Note: Standard sieve: square aperture 0.9 mm, with sieve cover and sieve bottom; plugging instrument: DL-07 type; slit plate: slit length 30 mm, slit width 1 mm; mixing device for preparing cement slurry meets the requirements of GB / T10238-2015; setting time tester; distilled water is three-grade water meeting the requirements of GB / T6682-2008; oil well cement: high-sulfate-resistant type (HSR) G-grade cement meeting the requirements of GB / T10238-2015; fluid loss additive: modified polyvinyl alcohol (Weicheng GJ-S); defoaming agent: organic phosphonate (FRSN9-1); take 304 g of distilled water, 48 g of GJ-S and 0.4 g of FRSN9-1 in a slurry cup of a cement slurry mixer, pass the Huayin G-grade oil well cement through a 0.9 mm sieve to remove lumps and impurities, and weigh 800 g. Weigh 3.2 g of modified glass fiber. Turn on the low speed 4000 r / min, pour the oil well cement into the slurry cup within 15 s, and immediately cover the slurry cup cover. Then turn on the high speed 12000 r / min, continue to stir for 35 s. Add the modified glass fiber, and continue to stir at low speed 4000 r / min for 50 s. Meanwhile, prepare a blank cement slurry without adding modified glass fiber. Determine the change rate of final setting time by preparing the test slurry and the blank cement slurry. Coat a thin layer of Handiyangguang No. 2 calcium-based lubricating grease between the inner surface of the setting test mold and the mold plate. It needs to be tightly assembled to prevent slurry leakage. Excess grease on the inner surface, especially in the corners, should be scraped off, and the test mold should be placed on a smooth bottom plate coated with grease. The contact line outside the test mold and the bottom plate should be coated with grease. Stir the test slurry and the blank cement slurry with a wooden stick, and pour them into the prepared two setting test molds to a depth of half, respectively. Use a 6 mm diameter glass or stainless steel rod to tamp 25 times, respectively. Then stir the remaining test slurry or blank cement slurry and pour it into the corresponding test mold to overflow, and tamp 25 times again to fill the corners. Then use a ruler to scrape off the excess test slurry or blank cement slurry from the top of the test mold, and cover it with a cover plate coated with grease. Place the test mold filled with the test slurry and the blank cement slurry into a 60℃ water bath for curing, and the test mold should be fully immersed in water. The first measurement is made when the test piece is in the water bath for 60 min. Take out the test piece from the curing water bath and remove the cover plate, place it under the test needle, lower the test needle to the surface of the cement slurry, tighten the screw, and then suddenly release it. The test needle vertically freely sinks into the cement slurry. Observe the test needle when it stops sinking or release the test needle 30 s later to read the needle. When the test needle sinks to 1 mm-0.5 mm from the surface of the cement slurry, it is in the final setting state. The time from the addition of all cement to the water to the final setting state is the final setting time, and the change rate of the final setting time is calculated. Under the condition that the outlet valve of the plugging tester is closed, pour the prepared cement slurry into the slurry cup.Cover the cup cover, connect the pressure pipeline, pressurize to 0.3MPa; Place the liquid collection cylinder with scale under the outlet; Slowly open the outlet valve, collect the leaked cement paste until no cement paste flows out or only filtrate flows out; Close the outlet valve, pressurize to 0.7MPa again; Slowly open the outlet valve, collect the leaked cement paste until no cement paste flows out or only filtrate flows out; Read the volume of the collected cement paste, which is the leakage amount. The thickening test is carried out according to the 9th chapter of GB / T19139-2012. Read the initial consistency and thickening time. The compressive strength test is carried out according to the 7th chapter of GB / T19139-2012.

Claims

1. A method for producing cement leakproof externally admixture modified glass fiber, comprising the steps of conventional water immersion, dehydration, cutting, drying to obtain chopped glass fiber, characterized in that, The method further comprises the following steps: (1) putting the chopped glass fiber into a kneader and adding 2-3% of coupling agent by mass of the chopped glass fiber for kneading treatment, and kneading for 5-10 minutes at a temperature of 100-120°C; the coupling agent is one or more of aluminum-zirconium coupling agent or aluminum-titanium composite coupling agent; (2) activation treatment: weighing 12-15 parts of polymeric calcium aluminate powder, 18-24 parts of polyvinyl alcohol, and 45-64 parts of hot water at 80-90°C, and then mixing the weighed components to obtain an activator; adding 5-10% of the activator by mass of the chopped glass fiber after the kneading in step (1) for stirring activation treatment, and drying at 60-70°C until constant weight to obtain activated chopped glass fiber; (3) infiltration modification: weighing the components according to the following weight ratio: 34-38 parts of amino silicone oil emulsion, 3-5 parts of silane coupling agent, 15-20 parts of EVA emulsion, and 65-75 parts of water, and uniformly mixing to obtain an infiltration liquid; immersing the activated chopped glass fiber in the infiltration liquid, and infiltrating for 30-40 minutes, taking out and drying and solidifying at 65-85°C for 0.5-1 hour to obtain the product.

2. The method of producing cement leak barrier externally added material modified glass fiber according to claim 1, characterized in that, The amino silicone oil emulsion in step (3) is SM-17 amino silicone oil emulsion with a solid content of 4-6%.

3. The method of producing cement leak barrier externally added material modified glass fiber according to claim 1, characterized in that, The EVA emulsion in step (3) is ethylene-vinyl acetate emulsion with a solid content of 2-3%.

4. The method of producing cement leak barrier externally added material modified glass fiber according to claim 1, characterized by, The silane coupling agent in step (3) is one of 3-glycidyloxypropyltrimethoxysilane or γ-methacryloyloxypropyltrimethoxysilane.

5. The method of producing cement leak barrier externally added material modified glass fiber according to claim 1, characterized by, The chopped glass fiber in step (1) has a diameter of 11-14 μm and a chopped length of 3-15 mm.