Film-coated plugging agent as well as preparation method and application thereof

Abstract

The invention provides a film-coated plugging agent as well as a preparation method and application thereof, and relates to the technical field of petroleum drilling. The film covering plugging agent comprises a modified resin material, a glass fiber grid material and an elastic material, the glass fiber grid material is in a sheet shape, the sheet-shaped glass fiber grid material is mutually stacked to form an irregular mesh-cage-shaped three-dimensional space structure, the mesh-cage-shaped three-dimensional space structure is filled with the elastic material, and the elastic material is arranged in the mesh-cage-shaped three-dimensional space structure. The modified resin material wraps the surfaces of the glass fiber grid material and the elastic material. The coating plugging agent provided by the invention has good temperature resistance and plugging performance, and can form a coating film on the surface of a well wall to reinforce the well wall and improve the stability of the well wall; meanwhile, a mesh cage formed by glass fibers and an elastic material can be used for plugging well wall cracks, and the plugging effect is improved; and in the crack plugging process, the resin can play a good retention role, so that the plugging effect can be further improved.

Description

Technical Field

[0001] This invention relates to the field of oil drilling technology, specifically to a coating plugging agent, its preparation method, and its application. Background Technology

[0002] Currently, fractured formations exhibit large leakage channels and rapid leakage rates, making it difficult to form a structurally stable, dense, and pressure-bearing sealing layer within the fractures. This results in significant challenges for on-site drilling fluid plugging operations, often leading to substantial economic losses. With the increasing prominence of drilling fluid leakage problems in complex formations, highly efficient leakage prevention and plugging materials have become crucial for the rapid and efficient treatment of well leakage. Domestic and international experts have conducted extensive research on leak prevention and plugging materials. Existing plugging materials can be classified into bridging plugging materials, high-water-loss plugging materials, temporary plugging materials, chemical plugging materials, inorganic cementitious plugging materials, and soft (hard) plugging materials according to different mechanisms and functions. However, the above-mentioned traditional plugging materials do not have intelligent characteristics and cannot deform according to formation temperature. When dealing with well leakage in large-aperture fractured wells, the use of conventional large-particle-size, high-density plugging materials has poor suspension stability, which leads to settling in the mud tank or in the wellbore when dealing with long open-hole sections. On the other hand, it may cause drill string blockage. In addition, traditional bridging plugging materials are highly sensitive to fractures and cannot effectively seal fractures adaptively. They do not have the rigidity, high strength, and expansion "one agent, multiple functions" function.

[0003] With increasing understanding of new materials, more and more resin materials are being applied to drilling plugging. Epoxy resin materials, by adding curing agents, can form a three-dimensional network structure, exhibiting excellent high-temperature resistance. In recent years, domestic and foreign scholars have conducted extensive research on the challenge of crack plugging during drilling. Intelligent plugging products made primarily from shape memory resin materials can achieve automatic bridging and plugging, protecting the reservoir; the plugging time and start-up temperature can be controlled. Thermoplastic resins possess phase change characteristics and shape memory functions, allowing them to better penetrate into fractures. Some resins with deformation functions can adaptively and effectively plug fractures. Wang Qi et al. prepared intelligent shape memory alloy plugging materials using Ni-Ti, Cu-Zn-Al, and other materials; the pressure resistance of this shape memory plugging material exceeds 30 MPa. Tian Lufei et al. successfully prepared a cement-based intelligent plugging material. This plugging material mainly consists of shape memory alloy (Ni-Ti), cement-based coatings, and fillers. After entering the formation, it is affected by temperature, causing the SMAs (shape memory resins) inside the material to deform, resulting in the cracking and detachment of the outer coating until it finally returns to a straight state. Multiple linear SMAs connect to form a bridging blockage, and the internal sodium carbonate causes the plugging fluid to solidify rapidly, promoting the sealing process. However, current shape memory resin plugging materials have problems such as low activation temperature, poor rigidity and toughness, and inability to match the safe construction window of drilling and completion in the field.

[0004] Overall, as a sealing material, resin needs to improve its temperature resistance and dispersion ability in solution to further enhance its sealing effect. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to provide a membrane-coated sealing agent, its preparation method and application, so as to improve the temperature resistance and leakage plugging performance of the membrane-coated sealing agent.

[0006] The objective of this invention is mainly achieved through the following technical solutions:

[0007] In a first aspect, the present invention provides a coating sealing agent comprising a modified resin material, a glass fiber mesh material, and an elastic material, wherein the glass fiber mesh material is in sheet form, and the sheet-like glass fiber mesh materials are stacked to form an irregular cage-like three-dimensional spatial structure, the elastic material fills the interior of the cage-like three-dimensional spatial structure, and the modified resin material coats the surfaces of the glass fiber mesh material and the elastic material.

[0008] As a specific embodiment of the present invention, the modified resin material is a maleic anhydride grafted modified resin; and / or, the glass transition temperature of the modified resin material is 104℃~150℃; preferably, the matrix resin of the maleic anhydride grafted modified resin includes at least one of polypropylene resin, polystyrene resin, and polyvinyl chloride resin.

[0009] As a specific embodiment of the present invention, the preparation method of the modified resin material includes: heating a mixture comprising a matrix resin, maleic anhydride, and benzoyl peroxide to 150°C to 220°C for melt grafting; preferably, the mass ratio of the matrix resin, maleic anhydride, and benzoyl peroxide is (7-12):(3-8):(0.1-0.3).

[0010] As a specific embodiment of the present invention, the elastic material includes at least one of elastic graphite, calcium carbonate, and rubber particles.

[0011] In one specific embodiment of the present invention, the average particle size of the elastic material is 0.1 mm to 1 mm.

[0012] As a specific embodiment of the present invention, the surface of the glass fiber mesh material is coated with a coupling agent; preferably, the coupling agent includes at least one of KH550, KH560, and KH580.

[0013] As a specific embodiment of the present invention, the width of the sheet-like glass fiber mesh material is 0.5cm to 1cm and the length is 0.5cm to 1cm.

[0014] As a specific embodiment of the present invention, based on the total mass of the coating sealing agent as 100%, the mass percentage of glass fiber mesh material is 51% to 75%, the mass percentage of elastic material is 15% to 30%, and the mass percentage of modified resin material is 10% to 19%.

[0015] Secondly, the present invention provides a method for preparing a membrane-sealing agent, comprising the following steps:

[0016] Step 1: Prepare modified resin materials;

[0017] Step 2: Stir the sheet-like glass fiber mesh material;

[0018] Step 3: Add the elastic material to the stirred sheet-like glass fiber mesh material and stir;

[0019] Step 4: Add the modified resin material and stir under heating conditions.

[0020] As a specific embodiment of the present invention, step 1 includes the following steps:

[0021] Step 1a: Mix the matrix resin, maleic anhydride, and benzoyl peroxide, and then heat to 150℃~220℃ for melt grafting;

[0022] Step 1b: After cooling, filtration, washing with hot water, and drying, the modified resin material is obtained.

[0023] As a specific embodiment of the present invention, before stirring the sheet-like glass fiber mesh material in step 2, a step of modifying the glass fiber mesh material by coating it with a coupling agent is also included.

[0024] In one specific embodiment of the present invention, in step 4, the heating temperature is 100℃~160℃. Preferably, in steps 2-4, the stirring conditions are the same or different, and each independently includes: stirring speed of 100-500r / min and stirring time of 10-60min.

[0025] Thirdly, the present invention provides an application of a coating sealing agent in well drilling engineering for plugging leaks, oil production water shut-off and profile control, and drilling fracturing.

[0026] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0027] A) The film-coating plugging agent provided by this invention has good temperature resistance and plugging performance. It can form a film on the surface of the well wall to reinforce the well wall and improve its stability. At the same time, it can use glass fiber and elastic materials to form a mesh cage to seal the cracks in the well wall and improve the plugging effect. During the crack plugging process, the resin can play a good retention role, thereby further improving the plugging effect. It can be used in deep well formation plugging and plugging operations.

[0028] B) The coating sealant provided by this invention is a block solid material. It uses resin material to bond elastic material into the space formed by glass fiber mesh to form a cage structure. This structure has a good sealing effect on large cracks and hole-type leaks. It is equivalent to pre-forming a series of sealing units, which improves the sealing speed and effect.

[0029] C) The film-coating plugging agent provided by this invention, after being lowered into the wellbore, the modified resin material reaches the glass transition temperature and undergoes a phase change, changing from a solid to a viscous liquid. It will coat the well wall to form a plugging layer, and at the same time, it will seal the mesh cage to the well wall, further enhancing the wall-fixing effect. Moreover, the resin has a retention effect on the plugging of large pores, preventing the plugging material from being diluted and washed away, thereby losing its plugging ability.

[0030] D) The membrane sealing agent provided by the present invention, before entering the well, uses modified resin material to bond glass fiber mesh material and elastic material together, thereby fixing the elastic material in the space formed by the mesh cage, achieving an effective filling effect. During transportation and wellbore entry, the elastic material will not move due to vibration or scouring, and will not leave the mesh cage space, thus improving the plugging effect. Detailed Implementation

[0031] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0032] As research has deepened, it has been discovered that interfacial modification plays a crucial and positive role in the functionalization of resins. Interfacial modification strengthens the interfacial wetting and adhesion of the system, increases interfacial interactions, and improves the overall mechanical properties of the system. Interfacial properties can be improved through resin matrix treatment. Daemen et al. modified PP with compounds containing COOH groups, significantly improving the mechanical properties of short glass fiber / PP composites. Li Zhijun et al. demonstrated that oxygen plasma treatment of polypropylene effectively improves the interfacial bonding of the material, greatly enhancing its mechanical properties and resistance to damp heat. Therefore, in the field of coating and sealing agents, resin modification can improve the overall performance of coating and sealing agents.

[0033] In a first aspect, the present invention provides a coating sealing agent comprising a modified resin material, a glass fiber mesh material, and an elastic material, wherein the glass fiber mesh material is in the form of sheets of different shapes, and the sheet-like glass fiber mesh materials are stacked to form an irregular cage-like three-dimensional spatial structure, the elastic material is filled inside the cage-like three-dimensional spatial structure, and the modified resin material is wrapped around the surface of the glass fiber mesh material and the elastic material.

[0034] It should be noted that the coating and plugging agent provided by the present invention can form a coating on the surface of the well wall, thereby reinforcing the well wall and improving its stability; at the same time, it can use glass fiber and elastic materials to form a mesh cage to seal the cracks in the well wall, thereby improving the plugging effect; during the crack plugging process, the resin can play a good retention role, thereby further improving the plugging effect, and it can be used in deep well formation sealing and plugging operations.

[0035] It should be noted that the film-sealing agent provided by the present invention uses modified resin material to bond elastic material into the space formed by glass fiber mesh to form a cage structure, thereby fixing the elastic material in the space formed by the mesh and achieving an effective filling effect. This structure has a good sealing effect for large cracks and pore-type leakage, which is equivalent to pre-forming a series of sealing units. During transportation and running into the wellbore, the elastic material will not move due to vibration or erosion and will not leave the cage space, thus improving the sealing speed and effect.

[0036] In one specific embodiment of the present invention, the modified resin material is a maleic anhydride grafted modified resin, which includes a matrix resin and a modifier. The matrix resin is selected from at least one of polypropylene resin, polystyrene resin, and polyvinyl chloride resin.

[0037] In one specific embodiment of the present invention, the modifier includes maleic anhydride and benzoyl peroxide. The preparation method of the modified resin material includes: melting and grafting a mixture comprising a matrix resin, maleic anhydride, and benzoyl peroxide to 150°C–220°C.

[0038] In one specific embodiment of the present invention, the mass ratio of the matrix resin, maleic anhydride, and benzoyl peroxide is (7-12):(3-8):(0.1-0.3).

[0039] It should be noted that the modified resin material provided by this invention is a thermoplastic resin, which undergoes a phase transition at its glass transition temperature, changing from a solid state to a viscous liquid state. As a specific embodiment of this invention, the modified resin material has a glass transition temperature of 104℃ to 150℃, and is a deformable resin material.

[0040] It should be noted that after being lowered into the wellbore, the modified resin material reaches its glass transition temperature, undergoing a phase change from solid to viscous liquid. This forms a film on the wellbore wall, creating a sealing layer and simultaneously securing the mesh cage to the wellbore wall, further enhancing the sealing effect. Furthermore, the resin has a retention effect on large pores, preventing the sealing material from being diluted or washed away, thus losing its sealing ability.

[0041] In one specific embodiment of the present invention, the elastic material is selected from at least one of elastic graphite, calcium carbonate, and rubber particles.

[0042] In one specific embodiment of the present invention, the average particle size of the elastic material is 0.1 mm to...

[0043] 1mm.

[0044] As a specific embodiment of the present invention, the mesh size of the glass fiber mesh material can be 4*4mm, 5*5mm, 7*8mm, etc.

[0045] As a specific embodiment of the present invention, the sheet-like glass fiber mesh material can be sheet-like in different shapes, such as circular, polygonal, etc. The polygonal shape can be triangular, square, rectangular, rhomboid, etc. The width of the sheet-like glass fiber mesh material can be 0.5cm to 1cm, and the length can be 0.5cm to 1cm.

[0046] As a specific embodiment of the present invention, the surface of the glass fiber mesh material is coated with a coupling agent.

[0047] As a specific embodiment of the present invention, the coupling agent is selected from one or more of KH550, KH560, and KH580.

[0048] It should be noted that the modification technology of resin and glass fiber is helpful in the construction of the wire mesh structure.

[0049] It should be noted that the resin modification in the membrane-sealing agent provided by this invention primarily results in a non-polar crystalline linear structure of resin molecules with low surface activity and non-polarity. This modification makes the membrane-sealing agent easier to disperse in water or plugging slurry, and the uniform dispersion contributes to improved plugging effectiveness. The modification of the glass fiber mesh fabric makes it easier for the resin to bond with the glass fiber mesh fabric and elastic materials, thus forming a solid structure. The resin coats the surfaces of the glass fiber mesh material and elastic materials, bonding them together at high temperatures. This fixes the elastic material within the space formed by the mesh, achieving effective filling. During transportation and installation into the wellbore, the elastic material will not move due to vibration or erosion, thus preventing it from detaching from the mesh space and achieving a true mesh cage effect, thereby improving the plugging effect.

[0050] As a specific embodiment of the present invention, the total mass of the coating sealing agent is taken as 100%:

[0051] The mass percentage of the glass fiber mesh material is 51% to 75%.

[0052] The mass percentage of elastic material is 15% to 30%;

[0053] The modified resin material comprises 10% to 19% by mass.

[0054] Secondly, the present invention provides a method for preparing a membrane-sealing agent, comprising the following steps:

[0055] Step 1: Prepare modified resin materials;

[0056] Step 2: Stir the sheet-like glass fiber mesh material to form an irregular cage-like three-dimensional spatial structure;

[0057] Step 3: Add elastic material to the stirred sheet-like glass fiber mesh material and continue stirring to fill the mesh cage space with elastic material;

[0058] Step 4: Add the modified resin material, stir and heat to make the modified resin material evenly coat the surface of the glass fiber mesh material and the elastic material.

[0059] As a specific embodiment of the present invention, step 1 includes the following steps:

[0060] Step 1a: Mix the matrix resin, maleic anhydride, and benzoyl peroxide evenly in a high-speed mixer, and then heat to 150℃~220℃ for melt grafting;

[0061] Step 1b: After cooling, filtration, washing with hot water until neutral, and vacuum drying, the modified resin material is obtained.

[0062] In one specific embodiment of the present invention, before stirring the sheet-like glass fibers in step 2, a step of modifying the glass fibers by coating them with a coupling agent is also included. Specifically, step 2 includes the following steps:

[0063] Step 2a: Modification of glass fiber mesh material: Apply coupling agent evenly to the surface of glass fiber mesh material and then dry;

[0064] Step 2b: Cut the modified glass fiber mesh material into sheet-like glass fiber mesh material, and then stir it evenly in a mixer to form a cage-like three-dimensional spatial structure.

[0065] In one specific embodiment of the present invention, in step 4, the heating temperature is 100℃~160℃ and the heating time is 1~5h.

[0066] As a specific embodiment of the present invention, the preparation method further includes step 5: taking out the product, cooling and solidifying it, and cutting and crushing the solidified product into block-shaped film-sealing agent with a width of 0.5cm to 1cm.

[0067] It should be noted that in step 2, stirring causes the sheet-like glass fiber mesh material to be irregularly stacked, forming spaces of varying sizes, thus creating a cage-like three-dimensional spatial structure. In step 3, while adding the elastic material, stirring continues, allowing the sheet-like glass fiber mesh material to form a cage-like three-dimensional spatial structure while simultaneously filling the cage-like three-dimensional spatial structure with the elastic material. In step 4, modified resin material is added, stirred, and heated, maintaining the filling of the spatial structure with the elastic material while ensuring that the modified resin material is evenly coated on the surfaces of the glass fiber and the elastic material.

[0068] It should be noted that the present invention does not limit the stirring method; as long as thorough stirring is achieved, such as by using a blade stirrer.

[0069] In one specific embodiment of the present invention, the stirring conditions in steps 2-4 may be the same or different, and each independently includes: stirring speed of 100-500 r / min, preferably 300 r / min, and stirring time of 10-60 min, preferably 0.5 h.

[0070] It should be noted that if the stirring speed is too slow, below 100 r / min, the cage space formed by the stacked structure of the sheet glass fiber mesh material will be uneven, and the filling of the elastic material will be uneven, affecting the properties of the coating and sealing agent product. If the stirring speed is too fast, above 500 r / min, the glass fiber mesh material will break, which will have an adverse effect on the properties of the coating and sealing agent product.

[0071] As a specific embodiment of the present invention, the specific steps of the above preparation method can be as follows:

[0072] 1) Modification of resin materials: The resin, maleic anhydride, benzoyl peroxide, etc. are weighed in a mass ratio of (7-12):(3-8):(0.1-0.3) and mixed evenly in a high-speed mixer. Then, the mixture is heated to 150℃-220℃ for melt grafting. After cooling, filtration, washing with hot water until neutral, and vacuum drying at 60℃ for 12 hours, the modified resin is obtained.

[0073] 2) Modification of glass fiber mesh material: Apply coupling agent evenly to the surface of glass fiber mesh material and then dry.

[0074] 3) Cut the modified glass fiber mesh material into sheet mesh material, and then stir it evenly in a mixer at a speed of 100-500 r / min, preferably 300 r / min, for a time of 10-60 min, preferably 0.5 h, so that the sheet mesh material forms a cage-like three-dimensional spatial structure.

[0075] 4) Add the elastic material and continue to stir evenly at a stirring speed of 100-500 r / min, preferably 300 r / min, for a stirring time of 10-60 min, preferably 0.5 h, so that the elastic material fills the space inside the mesh cage.

[0076] 5) Add the modified resin material and stir evenly. The stirring speed is 100-500 r / min, preferably 300 r / min, and the stirring time is 10-60 min, preferably 0.5 h. Then, put it into a roller heating furnace for rolling heating for 1-5 h. The heating temperature is 100℃-160℃, and the roller rolling speed is 30-100 r / min, preferably 50 r / min, so that the resin material is evenly coated on the surface of the glass fiber mesh material and the elastic material.

[0077] 6) Remove and cool to solidify, then cut and crush the solidified material into block-shaped film-sealing agent products with a width of 0.5cm to 1cm.

[0078] Thirdly, the present invention provides an application of a coating sealing agent in well drilling engineering for plugging leaks, oil production water shut-off and profile control, and drilling fracturing.

[0079] It should be noted that the coating sealant, its preparation method, and its application provided by this invention are prepared by coating glass fibers and elastic materials with resin. The coating sealant can form a film on the surface of the well wall, reinforcing the well wall and improving its stability. At the same time, the glass fibers and elastic materials can form a mesh cage to seal cracks in the well wall, improving the plugging effect. During the crack plugging process, the resin can play a good retention role, thereby further improving the plugging effect.

[0080] The following detailed description of preferred embodiments of the present invention illustrates the principles of the invention and is not intended to limit the scope of the invention.

[0081] In this invention, the high-temperature roller heating furnace was purchased from Qingdao Haitong Yuanda Instrument Co., Ltd., model XGRL-4.

[0082] In this invention, the universal testing machine was purchased from Jiangsu Tianyuan Testing Equipment Co., Ltd., model number TY8000.

[0083] Unless otherwise specified, the drying oven and oil bath can be commercially available in this invention.

[0084] In this invention, the wedge-shaped long crack sealing experimental device is a conventional experimental device in the field and was developed by China University of Petroleum (East China).

[0085] In this invention, the elastic graphite, calcium carbonate, and rubber granules were purchased from Shandong Zhongsheng Chemical Co., Ltd.

[0086] In this invention, the fiberglass mesh was purchased from Hebei Wucheng Wire Mesh Products Co., Ltd., with a thickness of 1mm and a mesh size of 4*4mm.

[0087] In this invention, maleic anhydride, benzoyl peroxide, polypropylene resin, polystyrene resin, and polyvinyl chloride resin were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0088] The coupling agents KH550, KH560, and KH580 used in this invention were purchased from Shandong Huachen New Materials Co., Ltd.

[0089] Example 1

[0090] This embodiment provides a coating sealing agent and its preparation method.

[0091] The raw materials for preparing the coating and plugging agent are: based on 100% of the total mass of the coating and plugging agent.

[0092] The mass percentage of the glass fiber mesh material is 51%.

[0093] The elastic material accounts for 30% of the total mass.

[0094] The modified resin material accounts for 19% by mass.

[0095] 1) Modification of resin material: Polystyrene resin, maleic anhydride and benzoyl peroxide were weighed in a mass ratio of 12:4:0.3 and mixed evenly in a high-speed mixer. Then, the mixture was heated to 150°C for melt grafting. After cooling, filtration, washing with hot water until neutral, and vacuum drying at 60°C for 12 hours, the modified resin material was obtained.

[0096] 2) Modification of glass fiber mesh: Coupling agent KH550 is evenly applied to the surface of glass fiber mesh and then dried.

[0097] 3) The modified glass fiber mesh is cut into 1cm wide sheet mesh materials, and then stirred evenly in a mixer at a speed of 300r / min for 0.5h to form a cage-like three-dimensional spatial structure.

[0098] 4) Add calcium carbonate and continue to stir evenly at a speed of 300 r / min for 0.5 h to allow the calcium carbonate to fill the space inside the mesh cage.

[0099] 5) Add the modified resin material, stir evenly, stir at 300 r / min for 0.5 h, then put it into a roller heating furnace for rolling heating for 5 h at 100℃ and 50 r / min, so that the modified resin material is evenly coated on the surface of the glass fiber mesh material and the elastic material.

[0100] 6) Remove and cool to solidify, then cut and crush the solidified material into block-shaped film-sealing agent products with a width of 0.5cm.

[0101] Example 2

[0102] This embodiment provides a coating sealing agent and its preparation method.

[0103] The raw materials for preparing the coating and plugging agent are: based on 100% of the total mass of the coating and plugging agent.

[0104] The mass percentage of the glass fiber mesh material is 62%.

[0105] The mass percentage of the elastic material is 27%;

[0106] The modified resin material accounts for 11% by mass.

[0107] 1) Modification of resin material: Polypropylene resin, maleic anhydride, benzoyl peroxide, etc. are weighed in a mass ratio of 10:5:0.2 and mixed evenly in a high-speed mixer. Then, the mixture is heated to 180℃ for melt grafting, cooled, filtered, washed with hot water until neutral, and then vacuum dried at 60℃ for 12 hours to obtain modified resin material.

[0108] 2) Modification of glass fiber mesh: Coupling agent KH550 is evenly applied to the surface of glass fiber mesh and then dried.

[0109] 3) Cut the modified glass fiber mesh into sheet-like mesh materials with a width of 0.5cm, and then stir them evenly in a mixer at a speed of 300r / min for 0.5h to form a cage-like three-dimensional spatial structure.

[0110] 4) Add elastic graphite and continue to stir evenly at a stirring speed of 300 r / min for 0.5 h to allow the elastic graphite to fill the space inside the mesh cage.

[0111] 5) Add the modified resin material, stir evenly at a stirring speed of 300 r / min for 0.5 h, and then put it into a roller heating furnace for rolling heating for 3 h at a heating temperature of 120℃ and a roller rolling speed of 50 r / min, so that the modified resin material is evenly coated on the surface of the glass fiber mesh material and the elastic material.

[0112] 6) Remove and cool to solidify, then cut and crush the solidified material into block-shaped film-sealing agent products with a width of 0.5cm.

[0113] Example 3

[0114] This embodiment provides a coating sealing agent and its preparation method.

[0115] The raw materials for preparing the coating and plugging agent are: based on 100% of the total mass of the coating and plugging agent.

[0116] The glass fiber mesh material comprises 75% by mass.

[0117] The elastic material comprises 15% by mass.

[0118] The modified resin material accounts for 10% by mass.

[0119] 1) Modification of resin material: Polyvinyl chloride resin, maleic anhydride and benzoyl peroxide were weighed in a mass ratio of 7:3:0.1 and mixed evenly in a high-speed mixer. Then, the mixture was heated to 220℃ for melt grafting. After cooling, filtration, washing with hot water until neutral, and vacuum drying at 60℃ for 12 hours, the modified resin material was obtained.

[0120] 2) Modification of glass fiber mesh: Coupling agent KH560 is evenly applied to the surface of glass fiber mesh and then dried.

[0121] 3) The modified glass fiber mesh is cut into sheet mesh materials with a width of 0.8cm. Then, it is stirred evenly in a mixer at a speed of 300r / min for 0.5h to form a cage-like three-dimensional spatial structure.

[0122] 4) Add rubber granules and continue to stir evenly at a speed of 300 r / min for 0.5 h, so that the rubber granules fill the space inside the mesh cage.

[0123] 5) Add the modified resin material, stir evenly, stir at 300 r / min for 0.5 h, then put it into a roller heating furnace for 1 h of rolling heating at 160℃ and roller speed of 50 r / min, so that the resin material is evenly coated on the surface of the glass fiber mesh material and the elastic material.

[0124] 6) Remove and cool to solidify, then cut and crush the solidified material into blocks with a width of 1cm for the coating sealant product.

[0125] Example 4

[0126] This embodiment is basically the same as Embodiment 1, except that: the raw materials for preparing the coating and sealing agent are: based on the total mass of the coating and sealing agent as 100%,

[0127] The fiberglass mesh material comprises 56% by mass.

[0128] The elastic material comprises 25% by mass;

[0129] The modified resin material accounts for 19% by mass.

[0130] Example 5

[0131] This embodiment is basically the same as Embodiment 1, except that: the raw materials for preparing the coating and sealing agent are: based on the total mass of the coating and sealing agent as 100%,

[0132] The fiberglass mesh material comprises 65% by mass.

[0133] The elastic material comprises 20% by mass.

[0134] The modified resin material accounts for 15% by mass.

[0135] Example 6

[0136] This embodiment is basically the same as embodiment 1, except that the heating temperature in step 1) of resin material modification is 165°C.

[0137] Example 7

[0138] This embodiment is basically the same as embodiment 1, except that: in step 5), the modified resin material is added and the heating temperature is 140°C.

[0139] Example 8

[0140] This embodiment is basically the same as that of Embodiment 1, except that the mass ratio of polystyrene resin, maleic anhydride and benzoyl peroxide in step 1) is 14:2:0.2.

[0141] Example 9

[0142] This embodiment provides a coating sealing agent and its preparation method. Compared with Example 2, the glass fiber is not modified.

[0143] The raw materials for preparing the coating and plugging agent are: based on 100% of the total mass of the coating and plugging agent.

[0144] The mass percentage of the glass fiber mesh material is 62%.

[0145] The mass percentage of the elastic material is 27%;

[0146] The modified resin material accounts for 11% by mass.

[0147] 1) Modification of resin material: Polypropylene resin, maleic anhydride, benzoyl peroxide, etc. are weighed in a mass ratio of 10:5:0.2 and mixed evenly in a high-speed mixer. Then, the mixture is heated to 180℃ for melt grafting, cooled, filtered, washed with hot water until neutral, and then vacuum dried at 60℃ for 12 hours to obtain modified resin material.

[0148] 2) Cut the fiberglass mesh into 0.5cm wide sheet mesh materials, then mix them evenly in a mixer at a speed of 300r / min for 0.5h to form a cage-like three-dimensional spatial structure.

[0149] 3) Add elastic graphite and continue to stir evenly at a stirring speed of 300 r / min for 0.5 h to allow the elastic graphite to fill the space inside the mesh cage.

[0150] 4) Add the modified resin material, stir evenly, stir at 300 r / min for 0.5 h, then put it into a roller heating furnace for 3 h of rolling heating at 120 ℃ and roller rolling speed of 50 r / min, so that the modified resin material is evenly coated on the surface of the glass fiber mesh material and the elastic material.

[0151] 5) Remove and cool to solidify, then cut and crush the solidified material into block-shaped film-sealing agent products with a width of 0.5cm.

[0152] Example 10

[0153] This embodiment is basically the same as Embodiment 1, except that the raw materials for preparing the coating and sealing agent are: based on the total mass of the coating and sealing agent as 100%,

[0154] The glass fiber content is 49% by weight.

[0155] The mass percentage of elastic material is 32%;

[0156] The resin material comprises 19% by mass.

[0157] Example 11

[0158] This embodiment is basically the same as Embodiment 1, except that the raw materials for preparing the coating and sealing agent are: based on the total mass of the coating and sealing agent as 100%,

[0159] The glass fiber content is 49% by weight.

[0160] The elastic material accounts for 30% of the total mass.

[0161] The resin material accounts for 21% of the total mass.

[0162] Example 12

[0163] This embodiment is basically the same as embodiment 1, except that the heating temperature in step 1) of resin material modification is 138°C.

[0164] Example 13

[0165] This embodiment is basically the same as embodiment 1, except that: in step 5), the modified resin material is added and the heating temperature is 92°C.

[0166] Comparative Example 1

[0167] This comparative example provides a coating sealing agent and its preparation method. It is basically the same as Example 2, except that the resin material is not modified.

[0168] The raw materials for preparing the coating and plugging agent are: based on 100% of the total mass of the coating and plugging agent.

[0169] The mass percentage of the glass fiber mesh material is 62%.

[0170] The mass percentage of the elastic material is 27%;

[0171] The resin material accounts for 11% of the total mass.

[0172] 1) Modification of glass fiber mesh: Coupling agent KH550 is evenly applied to the surface of glass fiber mesh and then dried.

[0173] 2) Cut the modified glass fiber mesh into sheet-like mesh materials with a width of 0.5cm, and then stir them evenly in a mixer at a speed of 300r / min for 0.5h to form a cage-like three-dimensional spatial structure.

[0174] 3) Add elastic graphite and continue to stir evenly at a stirring speed of 300 r / min for 0.5 h to allow the elastic graphite to fill the space inside the mesh cage.

[0175] 4) Add polypropylene resin, stir evenly, stir at 300 r / min for 0.5 h, then put it into a roller heating furnace for 3 h of rolling heating at 120 ℃ and roller rolling speed of 50 r / min, so that the resin material is evenly coated on the surface of the glass fiber mesh material and elastic material.

[0176] 5) Remove and cool to solidify, then cut and crush the solidified material into block-shaped film-sealing agent products with a width of 0.5cm.

[0177] Comparative Example 2

[0178] This comparative example provides a coating sealing agent and its preparation method. It is basically the same as Example 2, except that no elastic material is added.

[0179] The raw materials for preparing the coating and plugging agent are: based on 100% of the total mass of the coating and plugging agent.

[0180] The mass percentage of the glass fiber mesh material is 89%.

[0181] The modified resin material accounts for 11% by mass.

[0182] 1) Modification of resin materials: Polypropylene resin, maleic anhydride, benzoyl peroxide, etc. are weighed in a mass ratio of 10:5:0.2 and mixed evenly in a high-speed mixer. Then, the mixture is heated to 180°C for melt grafting, cooled, filtered, washed with hot water until neutral, and then vacuum dried at 60°C for 12 hours to obtain modified resin.

[0183] 2) Modification of glass fiber mesh: Coupling agent KH550 is evenly applied to the surface of glass fiber mesh and then dried.

[0184] 3) The modified glass fiber mesh is cut into sheet mesh materials with a width of 0.5cm. Then, it is stirred evenly in a mixer at a speed of 300r / min for 0.5h to form a cage-like three-dimensional spatial structure.

[0185] 4) Add the modified resin material, stir evenly, stir at 300 r / min for 0.5 h, then put it into a roller heating furnace for 3 h of rolling heating, with a roller rolling speed of 50 r / min and a heating temperature of 120℃, so that the resin material is evenly coated on the surface of the glass fiber mesh material.

[0186] 5) Remove and cool to solidify, then cut and crush the solidified material into block-shaped film-sealing agent products with a width of 0.5cm.

[0187] Experimental Example 1 - Temperature Resistance Test:

[0188] The test material was heated by rolling in a high-temperature roller furnace and then subjected to a high-temperature resistance evaluation test. The rolling heating temperature was 120℃ and the rolling heating time was 16h.

[0189]

[0190] In the above formula, α is the mass retention rate, %; M1 is the mass of the material before hot rolling, g; and M2 is the mass of the material after hot rolling, g.

[0191] Table 1

[0192]

[0193]

[0194] The results in Table 1 show that the coating and plugging agent prepared in the embodiments of the present invention has a high mass retention rate after high-temperature hot rolling, indicating that the coating and plugging agent prepared in the embodiments of the present invention has good temperature resistance. Furthermore, the mass retention rate of Embodiment 2 of the present invention is greater than that of Comparative Example 1, indicating that the modification of the resin has a very good effect on improving the temperature resistance of the coating and plugging agent.

[0195] Experiment Example 2: Leak-stopping performance test

[0196] The sealing performance of the membrane-coated sealing agents prepared in the embodiments and comparative examples of the present invention was evaluated.

[0197] An evaluation experiment was conducted using a wedge-shaped long crack sealing experimental device. The results of the leakage evaluation experiment are shown in the table below.

[0198] The basic formulation of the plugging fluid consists of bentonite slurry, walnut shells, sawdust, and ultrafine calcium carbonate. Based on the weight of the bentonite slurry, the amount of walnut shells added is 3 wt%, the amount of sawdust added is 3 wt%, and the amount of ultrafine calcium carbonate added is 4 wt%. A membrane sealing agent prepared in different embodiments is added to the basic formulation of the plugging fluid at an amount of 5 wt%.

[0199] Table 2

[0200]

[0201]

[0202] The results in Table 2 show that adding the membrane-sealing agent prepared in the embodiments of this invention to the basic formulation of the sealing fluid has a significantly better sealing effect than adding the membrane-sealing agent prepared in the comparative example. This results in the crack sealing area moving forward, the pressure bearing capacity of the sealing layer increasing significantly, and the crack leakage decreasing. Compared with Comparative Example 1, Example 2 shows that the crack sealing area moving forward and the crack leakage decreasing, indicating that the resin modification method has a better sealing effect than the unmodified product. The mesh structure has a better sealing effect for large cracks and pore-type leakage, which is equivalent to pre-forming individual sealing units, improving the sealing speed and effect, thereby giving the membrane-sealing agent better dispersibility and sealing performance.

[0203] Any numerical value mentioned in this invention, if there is only a two-unit interval between any minimum and any maximum value, includes all values ​​that increase by one unit each time from the minimum to the maximum value. For example, if the amount of a component, or the value of a process variable such as temperature, pressure, or time, is stated as 50-90, in this specification it means specifically listing values ​​such as 51-89, 52-88… and 69-71 and 70-71, etc. For non-integer values, it may be appropriately considered that a unit is 0.1, 0.01, 0.001, or 0.0001. These are merely some specifically specified examples. In this application, in a similar manner, all possible combinations of numerical values ​​between the listed minimum and maximum values ​​are considered to have been disclosed.

[0204] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A film-coated occlusive agent, characterized in that, The film plugging agent comprises a modified resin material, a glass fiber grid material and an elastic material, wherein the glass fiber grid material is in a sheet shape, the sheet-shaped glass fiber grid material is stacked to form an irregular mesh cage three-dimensional space structure, the elastic material is filled in the interior of the mesh cage three-dimensional space structure, and the modified resin material is wrapped on the surfaces of the glass fiber grid material and the elastic material.

2. The coated occlusive agent of claim 1, wherein, The modified resin material is a maleic anhydride grafted modified resin; and / or the glass transition temperature of the modified resin material is 104-150 DEG C. Preferably, The base resin of the maleic anhydride grafted modified resin comprises at least one of polypropylene resin, polystyrene resin and polyvinyl chloride resin. And / or the preparation method of the modified resin material comprises: heating a mixture comprising a base resin, maleic anhydride and benzoyl peroxide to 150-220 DEG C. for melt grafting; preferably, the mass ratio of the base resin, maleic anhydride and benzoyl peroxide is (7-12):(3-8):(0.1-0.3).

3. The membrane-coated occlusion agent according to any one of claims 1-2, characterized in that, The elastic material comprises at least one of elastic graphite, calcium carbonate and rubber particles; And / or the average particle size of the elastic material is 0.1-1 mm.

4. The film-coated occlusive agent according to any one of claims 1 to 3, characterized in that, The surface of the glass fiber grid material is coated with a coupling agent; preferably, the coupling agent comprises at least one of KH550, KH560 and KH580, And / or the width of the sheet-shaped glass fiber grid material is 0.5-1 cm, and the length is 0.5-1 cm.

5. The film-coated occlusive agent according to any one of claims 1 to 4, characterized in that, Taking the total mass of the film plugging agent as 100%, The mass percentage of the glass fiber grid material is 51-75%, The mass percentage of the elastic material is 15-30%, The mass percentage of the modified resin material is 10-19%.

6. A method for preparing the film-coated occlusive agent according to any one of claims 1 to 5, characterized in that, The method comprises the following steps: Step 1: preparing a modified resin material; Step 2: stirring the sheet-shaped glass fiber grid material; Step 3: adding the elastic material to the stirred sheet-shaped glass fiber grid material and stirring; Step 4: adding the modified resin material and stirring under heating.

7. The production method according to claim 6, wherein Step 1 comprises the following steps: Step 1a: mixing a base resin, maleic anhydride and benzoyl peroxide, and then heating to 150-220 DEG C. for melt grafting; Step 1b: after cooling, suction filtration and hot water washing, drying to obtain the modified resin material.

8. The production method according to any one of claims 6 to 7, characterized by, Before the sheet-shaped glass fiber grid material is stirred in step 2, the step of applying a coupling agent to the glass fiber grid material for modification is further included.

9. The production method according to any one of claims 6 to 8, characterized by, In step 4, the heating temperature is 100-160 DEG C. Preferably, in steps 2-4, the stirring conditions are the same or different, and each independently comprises: The stirring speed is 100-500 r / min, and the stirring time is 10-60 min.

10. The film plugging agent prepared by the method of any one of claims 1-5 or 6-9 is applied in drilling engineering plugging, oil production water plugging profile control and drilling fracturing.

Images