Water control agent for edge and bottom water thickened oil reservoir and preparation method and application thereof

Abstract

The application discloses a water control blocking agent for edge and bottom water thickened oil reservoir, which is composed of the following components in percentage of the total mass of the water control blocking agent: water-soluble resin 3-40%, flexible polymer 0.1-5%, coagulant 0.01-1%, suspending agent 0.01-2%, and water as the balance. The application also discloses a preparation method of the water control blocking agent for edge and bottom water thickened oil reservoir, which comprises the following steps: (1) pouring water into a reaction container according to the formula, and then sequentially adding water-soluble resin, suspending agent, oxygen scavenger and toughening agent according to the formula, stirring for at least 20 minutes to obtain a first mixed solution; (2) adding flexible polymer to the first mixed solution according to the formula, stirring at room temperature for at least 4 hours until completely dissolved to obtain a second mixed solution; and (3) adding coagulant to the second mixed solution according to the formula, and continuing to stir for at least 30 minutes to obtain the water control blocking agent for edge and bottom water thickened oil reservoir.

Description

Technical Field

[0001] This invention belongs to the field of heavy oil reservoir development technology, specifically relating to a water-controlling and plugging agent for edge-bottom water heavy oil reservoirs, its preparation method, and its application. Background Technology

[0002] Heavy oil generally refers to crude oil. Heavy oil is the residual heavy oil after gasoline and diesel are extracted from crude oil. It is characterized by its large molecular weight and high viscosity. The specific gravity of heavy oil is generally between 0.82 and 0.95, and its calorific value is between 10,000 and 11,000 kcal / kg. Its main components are hydrocarbons, with some sulfur and trace amounts of inorganic compounds.

[0003] Currently, the primary method for developing heavy oil reservoirs is thermal recovery, which includes methods such as steam injection, steam flooding, and thermochemical combined development. However, after multiple rounds of thermal recovery development, heavy oil reservoirs face the contradiction of declining energy and heat, resulting in increasingly poor development outcomes.

[0004] Horizontal wells have advantages such as long production intervals, large drainage area, and low bottom pressure drop, which can effectively improve the utilization of reserves and increase crude oil recovery rate. They are widely used in heavy oil reservoirs.

[0005] Edge-bottom water heavy oil reservoirs are among the most challenging types of heavy oil reservoirs to develop, facing the problems of both high oil viscosity and edge-bottom water intrusion. On one hand, after multiple rounds of steam huff and puff, edge-bottom water heavy oil reservoirs experience significant formation pressure drops, exacerbating reservoir heterogeneity and leading to increased edge-bottom water coning and high water channeling. On the other hand, the high production pressure differential required due to the difference in oil-water mobility in heavy oil intensifies the dynamic heterogeneity of the reservoir, resulting in significant water channeling in well sections with low oil saturation and high permeability.

[0006] Currently, this type of reservoir is mainly developed using horizontal wells. Due to factors such as edge and bottom water, thin oil layers, and heterogeneity, horizontal wells in near-half-water heavy oil reservoirs are in the ultra-high water-cut stage, resulting in high production costs per ton of oil and severely impacting their development efficiency.

[0007] Currently, existing water control systems for this type of reservoir mainly rely on polymeric gel-based plugging agents and particulate plugging agents. For example, Chinese patent CN115703891B discloses a method for preparing nanomaterial-reinforced gels. This involves dissolving an acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, then mixing it with a crosslinking agent, stabilizer, and nano-silica to obtain a gelling solution. After gelation, a nanomaterial-reinforced gel is obtained, which is temperature resistant up to 140℃. Another example is Chinese patent CN115059430B, which discloses a selective cone plugging method for oil wells in edge-bottom water reservoirs. In this method, the plugging agent is a multi-layered network gel formed by the polymerization and crosslinking of monomers such as acrylamide, acrylic acid, methyl methacrylate, and 2-acrylamido-2-methylpropanesulfonic acid. For example, Chinese patent application CN117248856A discloses a method for segmented water shut-off in a horizontal well of a heavy oil edge-bottom water reservoir, which includes at least the following steps: Step 1, determining whether the water outlet position of the horizontal well is the toe or the heel; Step 2, injecting a particulate water-absorbing gel plugging agent into the formation through the horizontal well; Step 3, if the water outlet position is at the toe, proceeding to Step 4; if the water outlet position is at the heel, injecting a predetermined amount of liquid bridge plug temporary plugging agent into the formation where the particulate water-absorbing gel plugging agent has been injected through the horizontal well, and then proceeding to Step 4; Step 4, injecting a high-strength, temperature-resistant inorganic sealing agent into the formation through the horizontal well; Step 5, if the water outlet position is at the toe, drilling to the predetermined toe position and then circulating and flushing the well; if the water outlet position is at the heel, drilling to the artificial bottom of the well and then circulating and flushing the well. The plugging agent used is a combination of particulate water-absorbing gel plugging agent and liquid bridge plug temporary plugging agent. For example, Chinese patent application CN117821042A discloses a deep-drive density-controllable multi-stage expansion pre-crosslinked gel particle and its preparation method. The particle synthesis monomers are acrylamide and triphenylethylphenol polyoxyethylene ether methacrylate, and the crosslinking agents are hydroquinone and hexamethylenetetramine. In addition, polyethylene glycol diacrylate, modified inorganic lightweight additives, and toughening agents are added to the system to improve the temperature resistance, sealing strength, and migration ability of the gel particles.

[0008] However, the plugging agents used in current water control technologies for edge-and-bottom water reservoirs are mostly acrylamide-based polymer gel materials. Under high-temperature conditions, acrylamide monomers are prone to hydrolysis, and the polymers are easily degraded, resulting in a short effective period for the plugging agents. Furthermore, plugging agents, such as polymer gels, have high viscosity before gelation and a short gelation time, making deep injection difficult; they are also diluted upon contact with edge-and-bottom water during formation migration, affecting gelation. Particulate plugging agents generally suffer from low plugging strength. Therefore, it is necessary to develop a suitable, high-temperature-resistant, high-plugging-strength water control system specifically tailored to the development characteristics of edge-and-bottom water heavy oil reservoirs. Summary of the Invention

[0009] Objective: To address the problems of acrylamide-based polymer gel materials used in edge and bottom water control in heavy oil reservoirs, which suffer from short-lived effectiveness due to the easy hydrolysis of acrylamide monomers and easy degradation of polymers under high-temperature conditions; high viscosity and short gelation time before gelation, making deep injection difficult; and dilution upon contact with edge and bottom water during formation migration, affecting gelation. This invention discloses a water control plugging agent for edge and bottom water heavy oil reservoirs, its preparation method, and its application. This invention utilizes a water-soluble resin as the main body of the plugging agent, adds a flexible, heat-resistant polymer as a second network polymer, adds a certain amount of inorganic salt as a coagulant, and adds an oxygen scavenger to improve the stability of the plugging agent, ultimately forming a water control plugging agent for edge and bottom water heavy oil reservoirs with a temperature resistance of 150℃.

[0010] Technical solution: A water-controlling and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs, is composed of the following components:

[0011] The composition consists of 3%-40% water-soluble resin, 0.1%-5% flexible polymer, 0.01%-1% coagulant, 0.01%-2% suspending agent, and the remainder is water.

[0012] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0013] (1) Pour the amount of water in the formula into the reaction vessel, and add the amount of water-soluble resin, the amount of suspending agent, the amount of oxygen scavenger and the amount of toughening agent in the formula in sequence. Stir for at least 20 minutes to obtain the first mixture.

[0014] (2) Add the formulated amount of flexible polymer to the first mixture and stir at room temperature for at least 4 hours until completely dissolved to obtain the second mixture;

[0015] (3) Add the formula amount of coagulant to the second mixture and continue stirring for at least 30 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0016] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0017] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0018] The functions of each component in this invention are as follows:

[0019] Water-soluble resin: Used as the main body of the plugging agent, the aqueous solution of water-soluble resin is a low-viscosity fluid, which has the advantage of easy injection; under certain temperature and mineralization conditions, the water-soluble resin molecules undergo a polymerization reaction and gradually solidify.

[0020] Flexible polymer: Used as a second network polymer in the plugging agent. On one hand, the introduction of the flexible polymer can form an interpenetrating network structure with the rigid resin structure (the structure formed by the cured water-soluble resin), greatly improving the toughness of the plugging agent. On the other hand, the flexible polymer molecules used have amide groups, which can react with the preferred water-soluble resin at high temperatures, further increasing the crosslinking density of the plugging agent, thereby improving the strength of the plugging agent.

[0021] Coagulant: After dissolving in water, it can compress the diffuse electric double layer of water-soluble resin, thereby increasing the collision probability between water-soluble resin molecules and playing a coagulant role.

[0022] Oxygen scavenger: As a sacrificial agent, it preferentially reacts with dissolved oxygen in the water to prevent the polymer from undergoing oxidative degradation, thereby improving the stability of the plugging agent.

[0023] Toughening agent: It does not chemically react with other components in the plugging agent and plays a role in providing physical support. When subjected to external force, the toughening agent in the plugging agent deforms and disperses stress, avoiding stress concentration inside the plugging agent, thereby improving the toughness of the plugging agent.

[0024] Suspension agents, as surfactants, are used to improve the wettability of toughening agents, thereby enhancing the suspension properties of toughening agents in plugging agents.

[0025] Beneficial Effects: The water-controlling and plugging agent for edge-bottom water heavy oil reservoirs disclosed in this invention, its preparation method, and its application have the following beneficial effects:

[0026] 1. The plugging agent has high strength, and its storage modulus after gelation is >1200Pa, which can effectively block high-permeability channels in the formation;

[0027] 2. The plugging agent has high thermal stability; after aging at 150℃ for 180 days, the dehydration rate is <10%, and the sealing effect is long.

[0028] 3. The plugging agent has low viscosity, less than 150 mPa·s at room temperature, which allows for large-volume injection into deep formations to achieve deep profile control.

[0029] 4. When used for water control in heavy oil reservoirs with water at the edge and bottom, it can block water channeling, increase the sweep efficiency, and improve crude oil recovery.

[0030] 5. Low construction risk, high success rate, and long validity period;

[0031] 6. Water-soluble resin, as the main plugging agent, is cured under the promotion of a coagulant. It has the advantages of low initial viscosity, easy injection, stability at high temperature, and long-term sealing. Attached Figure Description

[0032] Figure 1This is a flowchart of a method for preparing a water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water, as disclosed in this invention. Detailed Implementation

[0033] The specific embodiments of the present invention are described in detail below.

[0034] The "range" disclosed in this invention is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 10–50 is listed for a specific parameter, it is also expected that ranges of 10–40 and 20–50 are also included. Furthermore, if the minimum range values ​​are 1 and 2, and the maximum range values ​​are 3, 4, and 5, then the following ranges are all expected: 1–3, 1–4, 1–5, 2–3, 2–4, and 2–5. In this application, unless otherwise stated, the numerical range "a–b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0–5" means that all real numbers between "0–5" have been listed herein; "0–5" is merely a shortened representation of these numerical combinations.

[0035] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0036] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0037] Unless otherwise specified, all steps in this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0038] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0039] Unless otherwise specified, the reaction will proceed under normal temperature and pressure conditions.

[0040] Unless otherwise specified, all parts or percentages are by weight or by weight percentage.

[0041] In this invention, all the substances used are known substances that can be purchased or synthesized by known methods.

[0042] In this invention, all the devices or equipment used are conventional devices or equipment known in the art and are readily available.

[0043] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0044] The composition consists of 3%-40% water-soluble resin, 0.1%-5% flexible polymer, 0.01%-1% coagulant, 0.01%-2% suspending agent, and the remainder is water.

[0045] Further, the composition includes 5%-20% water-soluble resin, 0.5%-4% flexible polymer, 0.05%-0.2% coagulant, 0.1%-1% suspending agent, and the remainder is water.

[0046] Furthermore, it also includes 0.05%-2% oxygen scavenger, preferably 0.1%-0.5%.

[0047] Furthermore, it also includes 0.1%-5% toughening agent, preferably 0.5%-5%.

[0048] Furthermore, the water-soluble resin is one or more of water-soluble phenolic resin, water-soluble urea-formaldehyde resin, and water-soluble furan resin, preferably water-soluble phenolic resin.

[0049] Furthermore, the water-soluble resin has a viscosity-average molecular weight of 100,000 to 2,000,000.

[0050] Furthermore, the flexible polymer is one or more of polyvinylpyrrolidone, acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate copolymer, and acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, preferably acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer.

[0051] Furthermore, the viscosity-average molecular weight of the flexible polymer is 2 million to 20 million, preferably 2 million to 4 million.

[0052] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate copolymer is copolymerized from an equimolar ratio of acrylamide monomer and sodium 2-acrylamido-2-methylpropanesulfonate monomer, and / or

[0053] The acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

[0054] Furthermore, the coagulant is one or more of sodium chloride, calcium chloride, magnesium chloride, and aluminum chloride, preferably sodium chloride.

[0055] Furthermore, the oxygen scavenger is one or more of thiourea, sodium sulfite, and urea, with thiourea being preferred.

[0056] Furthermore, the toughening agent is one or more of fly ash, slag, ultrafine cement, and cellulose, preferably cellulose.

[0057] Furthermore, the molecular weight of the cellulose is 50,000-250,000, preferably 50,000-80,000.

[0058] Furthermore, the average particle size of fly ash, slag, and ultrafine cement is 5-100 μm.

[0059] Furthermore, the suspending agent is one or more of polyoxyethylene sorbitan fatty acid ester, sodium lauryl sulfate, dodecylphenol polyoxyethylene ether, and cocamidopropyl hydroxysulfonate betaine.

[0060] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0061] (1) Pour the amount of water in the formula into the reaction vessel, and add the amount of water-soluble resin, the amount of suspending agent, the amount of oxygen scavenger and the amount of toughening agent in the formula in sequence. Stir for at least 20 minutes to obtain the first mixture.

[0062] (2) Add the formulated amount of flexible polymer to the first mixture and stir at room temperature for at least 4 hours until completely dissolved to obtain the second mixture;

[0063] (3) Add the formula amount of coagulant to the second mixture and continue stirring for at least 30 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0064] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0065] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0066] In one embodiment:

[0067] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0068] The composition consists of 3% water-soluble resin, 0.1% flexible polymer, 0.01% coagulant, 0.01% suspending agent, and the remainder is water.

[0069] Furthermore, it also includes 0.05% oxygen scavenger.

[0070] Furthermore, it also includes 0.1% toughening agent.

[0071] Furthermore, the water-soluble resin is a water-soluble phenolic resin.

[0072] Furthermore, the water-soluble phenolic resin has a viscosity-average molecular weight of 100,000.

[0073] Furthermore, the flexible polymer is polyvinylpyrrolidone.

[0074] Furthermore, the viscosity-average molecular weight of the flexible polymer is 2 million.

[0075] Furthermore, the coagulant is sodium chloride.

[0076] Furthermore, the oxygen scavenger is thiourea.

[0077] Furthermore, the toughening agent is fly ash.

[0078] Furthermore, the average particle size of fly ash is 5 μm.

[0079] Furthermore, the suspending agent is polyoxyethylene sorbitan fatty acid ester.

[0080] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0081] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble resin, suspending agent, oxygen scavenger and toughening agent of the formula in sequence. Stir for 20 minutes to obtain the first mixture.

[0082] (2) Add the formulated amount of flexible polymer to the first mixture and stir at room temperature for 4 hours until completely dissolved to obtain the second mixture;

[0083] (3) Add the formula amount of coagulant to the second mixture and continue stirring for 30 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0084] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by the above-mentioned preparation method.

[0085] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0086] In another embodiment:

[0087] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0088] The composition consists of 40% water-soluble resin, 5% flexible polymer, 1% coagulant, 2% suspending agent, and the remainder is water.

[0089] Furthermore, it also includes 2% oxygen scavenger.

[0090] Furthermore, it also includes 5% toughening agent.

[0091] Furthermore, the water-soluble resin is a water-soluble urea-formaldehyde resin.

[0092] Furthermore, the water-soluble urea-formaldehyde resin has a viscosity-average molecular weight of 2 million.

[0093] Furthermore, the flexible polymer is an acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate copolymer.

[0094] Furthermore, the viscosity-average molecular weight of the flexible polymer is 20 million.

[0095] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate copolymer is copolymerized from acrylamide monomer and sodium 2-acrylamido-2-methylpropanesulfonate monomer in an equimolar ratio.

[0096] Furthermore, the coagulant is calcium chloride.

[0097] Furthermore, the oxygen scavenger is sodium sulfite.

[0098] Furthermore, the toughening agent is slag.

[0099] Furthermore, the average particle size of the slag is 100 μm.

[0100] Furthermore, the suspending agent is sodium dodecyl sulfate.

[0101] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0102] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble resin, suspending agent, oxygen scavenger and toughening agent of the formula in sequence. Stir for 60 minutes to obtain the first mixture.

[0103] (2) Add the formulated amount of flexible polymer to the first mixture and stir at room temperature for 8 hours until completely dissolved to obtain the second mixture;

[0104] (3) Add the formula amount of coagulant to the second mixture and continue stirring for 120 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0105] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by the above-mentioned preparation method.

[0106] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0107] In yet another embodiment:

[0108] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0109] The composition consists of 5% water-soluble resin, 0.5% flexible polymer, 0.05% coagulant, 0.1% suspending agent, and the remainder is water.

[0110] Furthermore, it also includes 0.1% oxygen scavenger.

[0111] Furthermore, it also includes 0.5% toughening agent.

[0112] Furthermore, the water-soluble resin is a water-soluble furan resin.

[0113] Furthermore, the water-soluble furan resin has a viscosity-average molecular weight of 1 million.

[0114] Furthermore, the flexible polymer is an acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer.

[0115] Furthermore, the viscosity-average molecular weight of the flexible polymer is 4 million.

[0116] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

[0117] Furthermore, the coagulant is magnesium chloride.

[0118] Furthermore, the oxygen scavenger is urea.

[0119] Furthermore, the toughening agent is ultrafine cement.

[0120] Furthermore, the average particle size of the ultrafine cement is 10 μm.

[0121] Furthermore, the suspending agent is dodecylphenol polyoxyethylene ether.

[0122] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0123] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble resin, suspending agent, oxygen scavenger and toughening agent of the formula in sequence. Stir for 40 minutes to obtain the first mixture.

[0124] (2) Add the formulated amount of flexible polymer to the first mixture and stir at room temperature for 6 hours until completely dissolved to obtain the second mixture;

[0125] (3) Add the formula amount of coagulant to the second mixture and continue stirring for 60 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0126] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0127] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0128] In yet another embodiment:

[0129] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0130] The composition consists of 20% water-soluble resin, 4% flexible polymer, 0.2% coagulant, 1% suspending agent, and the remainder is water.

[0131] Furthermore, it also includes 0.5% oxygen scavenger.

[0132] Furthermore, it also includes 5% toughening agent.

[0133] Furthermore, the water-soluble resin is a mixture of water-soluble phenolic resin, water-soluble urea-formaldehyde resin, and water-soluble furan resin in a mass ratio of 1:1:1.

[0134] Furthermore, the viscosity-average molecular weight of water-soluble phenolic resin is 500,000, that of water-soluble urea-formaldehyde resin is 600,000, and that of water-soluble furan resin is 920,000.

[0135] Furthermore, the flexible polymer is a mixture of polyvinylpyrrolidone, acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate copolymer, and acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, with a mass ratio of 1:1:1.

[0136] Furthermore, the viscosity-average molecular weight of polyvinylpyrrolidone is 2 million; the viscosity-average molecular weight of acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate copolymer is 6 million; and the viscosity-average molecular weight of acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is 20 million.

[0137] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate copolymer is copolymerized from an equimolar ratio of acrylamide monomer and sodium 2-acrylamido-2-methylpropanesulfonate monomer, and / or

[0138] The acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

[0139] Furthermore, the coagulant is aluminum chloride.

[0140] Furthermore, the oxygen scavenger is a mixture of thiourea, sodium sulfite, and urea in equal mass ratios.

[0141] Furthermore, the toughening agent is cellulose.

[0142] Furthermore, the molecular weight of the cellulose is 50,000. In another embodiment, the molecular weight of the cellulose is 250,000. In another embodiment, the molecular weight of the cellulose is 80,000. In yet another embodiment, the molecular weight of the cellulose is 60,000.

[0143] Furthermore, the suspending agent is cocamidopropyl hydroxysulfonate betaine.

[0144] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0145] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble resin, suspending agent, oxygen scavenger and toughening agent of the formula in sequence. Stir for 35 minutes to obtain the first mixture.

[0146] (2) Add the formulated amount of flexible polymer to the first mixture and stir at room temperature for 7 hours until completely dissolved to obtain the second mixture;

[0147] (3) Add the formula amount of coagulant to the second mixture and continue stirring for 90 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0148] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0149] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0150] In yet another embodiment:

[0151] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0152] The composition consists of 10% water-soluble resin, 2% flexible polymer, 0.1% coagulant, 0.5% suspending agent, and the remainder is water.

[0153] Furthermore, it also includes 0.3% oxygen scavenger.

[0154] Furthermore, it also includes 1% toughening agent.

[0155] Furthermore, the water-soluble resin is a water-soluble phenolic resin.

[0156] Furthermore, the water-soluble phenolic resin has a viscosity-average molecular weight of 1.5 million.

[0157] Furthermore, the flexible polymer is an acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer.

[0158] Furthermore, the viscosity-average molecular weight of the flexible polymer is 10 million.

[0159] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

[0160] Furthermore, the coagulant is a mixture of sodium chloride, calcium chloride, magnesium chloride, and aluminum chloride in equal mass ratios.

[0161] Furthermore, the oxygen scavenger is a mixture of thiourea and sodium sulfite in equal mass ratios.

[0162] Furthermore, the toughening agent is a mixture of fly ash, slag, ultrafine cement, and cellulose in equal mass ratios.

[0163] Furthermore, the molecular weight of the cellulose is 70,000.

[0164] Furthermore, the average particle size of fly ash is 20 μm. The average particle size of slag is 50 μm. The average particle size of ultrafine cement is 80 μm.

[0165] Furthermore, the suspending agent is a mixture of polyoxyethylene sorbitan fatty acid ester, sodium lauryl sulfate, dodecylphenol polyoxyethylene ether, and cocamidopropyl hydroxysulfonate in equal mass ratios.

[0166] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0167] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble resin, suspending agent, oxygen scavenger and toughening agent of the formula in sequence. Stir for 60 minutes to obtain the first mixture.

[0168] (2) Add the formulated amount of flexible polymer to the first mixture and stir at room temperature for 6 hours until completely dissolved to obtain the second mixture;

[0169] (3) Add the formula amount of coagulant to the second mixture and continue stirring for 150 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0170] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0171] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0172] Example 1

[0173] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0174] The composition consists of 10% water-soluble phenolic resin, 0.3% acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, 0.1% sodium chloride, 0.2% thiourea, 1.0% cellulose, 0.2% OP-10 (dodecylphenol polyoxyethylene ether), and the balance being water.

[0175] Furthermore, the water-soluble phenolic resin has a viscosity-average molecular weight of 880,000.

[0176] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

[0177] Furthermore, the molecular weight of the cellulose is 60,000.

[0178] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0179] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble phenolic resin, OP-10, thiourea and cellulose of the formula in sequence. Stir for 20 minutes to obtain the first mixture.

[0180] (2) Add the formulated amount of acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer to the first mixture, and stir at room temperature for 4 hours until completely dissolved to obtain the second mixture;

[0181] (3) Add the prescribed amount of sodium chloride to the second mixture and continue stirring for 30 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0182] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0183] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0184] Example 2

[0185] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0186] The composition consists of 15% water-soluble phenolic resin, 0.3% acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, 0.1% sodium chloride, 0.2% thiourea, 1.0% cellulose, 0.2% OP-10 (dodecylphenol polyoxyethylene ether), and the balance being water.

[0187] Furthermore, the viscosity-average molecular weight of the water-soluble phenolic resin is 880,000.

[0188] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

[0189] Furthermore, the molecular weight of the cellulose is 60,000.

[0190] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0191] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble phenolic resin, OP-10, thiourea and cellulose of the formula in sequence. Stir for 20 minutes to obtain the first mixture.

[0192] (2) Add the formulated amount of acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer to the first mixture, and stir at room temperature for 4 hours until completely dissolved to obtain the second mixture;

[0193] (3) Add the prescribed amount of sodium chloride to the second mixture and continue stirring for 30 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0194] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0195] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0196] Example 3

[0197] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0198] The composition consists of 10% water-soluble phenolic resin, 2.0% acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, 0.1% sodium chloride, 0.2% thiourea, 1.0% cellulose, 0.2% OP-10 (dodecylphenol polyoxyethylene ether), and the balance being water.

[0199] Furthermore, the water-soluble phenolic resin has a viscosity-average molecular weight of 880,000.

[0200] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

[0201] Furthermore, the molecular weight of the cellulose is 60,000.

[0202] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0203] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble phenolic resin, OP-10, thiourea and cellulose of the formula in sequence. Stir for 20 minutes to obtain the first mixture.

[0204] (2) Add the formulated amount of acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer to the first mixture, and stir at room temperature for 4 hours until completely dissolved to obtain the second mixture;

[0205] (3) Add the prescribed amount of sodium chloride to the second mixture and continue stirring for 30 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0206] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0207] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0208] Example 4

[0209] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0210] The composition consists of 10% soluble phenolic resin, 0.3% acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, 0.5% sodium chloride, 0.2% thiourea, 1.0% cellulose, 0.2% OP-10 (dodecylphenol polyoxyethylene ether), and the balance being water.

[0211] Furthermore, the water-soluble phenolic resin has a viscosity-average molecular weight of 880,000.

[0212] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

[0213] Furthermore, the molecular weight of the cellulose is 60,000.

[0214] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0215] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble phenolic resin, OP-10, thiourea and cellulose of the formula in sequence. Stir for 20 minutes to obtain the first mixture.

[0216] (2) Add the formulated amount of acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer to the first mixture, and stir at room temperature for 4 hours until completely dissolved to obtain the second mixture;

[0217] (3) Add the prescribed amount of sodium chloride to the second mixture and continue stirring for 30 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0218] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0219] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0220] Example 5

[0221] A water-control and plugging agent for edge-bottom water heavy oil reservoirs, based on the total mass of the water-control and plugging agent for edge-bottom water heavy oil reservoirs, comprises the following components:

[0222] The composition consists of 10% water-soluble phenolic resin, 0.3% acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, 0.5% sodium chloride, 0.2% thiourea, 3.0% cellulose, 0.2% OP-10 (dodecylphenol polyoxyethylene ether), and the balance being water.

[0223] Furthermore, the water-soluble phenolic resin has a viscosity-average molecular weight of 880,000.

[0224] Furthermore, the acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

[0225] Furthermore, the molecular weight of the cellulose is 60,000.

[0226] A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of the above claims, comprising the following steps:

[0227] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble phenolic resin, OP-10, thiourea and cellulose of the formula in sequence. Stir for 20 minutes to obtain the first mixture.

[0228] (2) Add the formulated amount of acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer to the first mixture, and stir at room temperature for 4 hours until completely dissolved to obtain the second mixture;

[0229] (3) Add the prescribed amount of sodium chloride to the second mixture and continue stirring for 30 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

[0230] A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water is prepared by any one of the preparation methods described above.

[0231] The above-mentioned water-control and plugging agents for edge-bottom water heavy oil reservoirs are used as water-control and plugging agents in the development of edge-bottom water heavy oil reservoirs.

[0232] Comparative Example 1

[0233] A plugging agent, based on its total mass, comprises the following components:

[0234] The composition consists of 3% water-soluble phenolic resin, 0.3% acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, 0.5% sodium chloride, 0.2% thiourea, 1.0% cellulose, 0.2% OP-10, and the balance being water.

[0235] That is, the content of water-soluble phenolic resin in Comparative Example 1 was reduced to below 10% (3%).

[0236] The preparation method of the above-mentioned plugging agent includes the following steps:

[0237] (1) Pour the water of the formula into the reaction vessel, and add the water-soluble phenolic resin, OP-10, thiourea and cellulose of the formula in sequence. Stir for 20 minutes to obtain the first mixture.

[0238] (2) Add the formulated amount of acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer to the first mixture, and stir at room temperature for 4 hours until completely dissolved to obtain the second mixture;

[0239] (3) Add the prescribed amount of sodium chloride to the second mixture and continue stirring for 30 minutes to obtain the blockage agent.

[0240] Test case

[0241] The water-control plugging agents for edge-bottom water heavy oil reservoirs prepared in Examples 1-5, and the plugging agent prepared in Comparative Example 1, were used to determine the viscosity before plugging at 150°C, gelation time, storage modulus after gelation, and dehydration rate after 180 days of aging.

[0242] (1) Prepare the plugging agent according to the specified ratio, stir evenly, and then measure the 7.34s using an Anton Paar MCR 101 shear rheometer. -1 The viscosity at that point.

[0243] (2) Pour 50g of the sealant into a heat-resistant glass tube with a stopper and age it in an oven at 150℃. After a period of time, take it out and invert the glass tube. If the sealant loses its fluidity, it is considered to have gelled. Record the aging time as the gelling time.

[0244] (3) Pour 50g of plugging agent into a stoppered heat-resistant glass tube and age it in an oven at 150℃. After aging for 3 days, take it out and use an Anton Paar MCR 101 shear rheometer to determine the storage modulus of the plugging agent at 1% strain and 1Hz frequency.

[0245] (4) After the plugging agent in step (3) has aged for 180 days, remove the glass tube, weigh the water in the glass tube, and measure the dehydration rate:

[0246] Dehydration rate = (mass of water / 50g) × 100%

[0247] The experimental results are shown in Table 1.

[0248] Table 1 Experimental Results

[0249]

[0250]

[0251] As can be seen from Table 1:

[0252] The water-control plugging agent prepared in Example 1 has a low viscosity before gelation, only 42 mPa·s, and a gelation time of up to 4.5 hours, exhibiting good injection capability in the formation. After gelation, it has high strength, with a storage modulus of up to 1432 Pa, and the plugging agent has temperature stability, with a dehydration rate of only 5.6% after aging at 150℃ for 180 days.

[0253] The experimental data from Examples 1-5 show that increasing the amount of water-soluble resin can increase the strength of the plugging agent and slightly reduce the dehydration rate, while the viscosity before gelation and the gelation time remain basically unchanged. Increasing the amount of flexible polymer leads to an increase in the viscosity of the plugging agent before gelation and a slight decrease in the gelation time, but the strength after gelation is significantly improved, and the dehydration rate decreases after aging for 180 days. As shown in Example 4, increasing the amount of coagulant leads to a significant shortening of the gelation time and an increase in the dehydration rate of the plugging agent.

[0254] The experimental data from Comparative Example 1 show that when the amount of water-soluble resin is reduced to 3%, the blocker no longer forms a gel.

[0255] Application examples

[0256] The water-control and plugging agent for heavy oil reservoirs with edge and bottom water prepared in Example 1 was applied in nine wells in the field:

[0257] Application Example 1

[0258] Well #1 was put into production in January 2015. Initially, the water cut was 50%. It was located in a high structural position. The water cut was high due to the edge water advance. Before the measures, the water cut was 96.2%, and the surface crude oil viscosity was 3680 mPa.s.

[0259] To increase production, a gas segmentation water control method for edge-bottom water heavy oil reservoirs was adopted. 250 cubic meters of the edge-bottom water heavy oil reservoir water control plugging agent prepared in Example 1 was injected, followed by 42,000 standard cubic meters of pre-nitrogen slug, 125 tons of carbon dioxide, and 35,000 standard cubic meters of post-nitrogen slug.

[0260] After implementation, the peak daily oil production increased by 5.8 tons compared to before implementation, lasting for more than 6 months, with a cumulative net increase of 729.9 tons of oil (see Table 2 for details).

[0261] Table 21# Well Gas Segmentation Water Control Method Construction Slug and Dosage Design

[0262]

[0263] Application Example 2

[0264] Well No. 2 was put into production in May 2015. Initially, the water cut was 45%. It was located in a high structural position. The water cut was high due to the edge water advance. Before the measures, the water cut was 98.7%, and the surface crude oil viscosity was 7760 mPa.s.

[0265] To increase production, a gas segmentation water control method for edge-bottom water heavy oil reservoirs was adopted. 200 cubic meters of the edge-bottom water heavy oil reservoir water control plugging agent prepared in Example 1 was injected, followed by 40,000 standard cubic meters of pre-nitrogen slug, 125 tons of carbon dioxide, and 35,000 standard cubic meters of post-nitrogen slug.

[0266] After implementation, the peak daily oil production increased by 6.0 t / d compared to before implementation, lasting for more than 6 months, with a cumulative net increase of 723.8 tons of oil (see Table 3 for details).

[0267] Table 32# Well Gas Segmentation Water Control Method Construction Slug and Dosage Design

[0268]

[0269] Application Example 3

[0270] Well No. 3 was put into production in August 2015. Initially, the water cut was 65%. It was located in a high structural position and the crude oil viscosity was high. The edge water fingering was serious. Before the measures were taken, the water cut was 97.1% and the surface crude oil viscosity was 27760 mPa.s.

[0271] To increase production, a gas segmentation water control method for edge-bottom water heavy oil reservoirs was adopted. 180 cubic meters of the edge-bottom water heavy oil reservoir water control plugging agent prepared in Example 1 was injected, followed by 40,000 standard cubic meters of pre-nitrogen slug, 125 tons of carbon dioxide, 10 tons of viscosity reducer, and 35,000 standard cubic meters of post-nitrogen slug.

[0272] After implementation, the peak daily oil production increased by 5.0 t / d compared to before implementation, lasting for more than 5 months, with a cumulative net increase of 476.2 tons of oil (see Table 4 for details).

[0273] Table 43# Well Gas Segmentation Water Control Method Construction Slug and Dosage Design

[0274]

[0275] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water, characterized in that, Based on the total mass of the water-control and plugging agent for the edge-bottom water heavy oil reservoir, it consists of the following components: The composition consists of 3%-40% water-soluble resin, 0.1%-5% flexible polymer, 0.01%-1% coagulant, 0.01%-2% suspending agent, and the remainder is water.

2. The water-controlling and plugging agent for edge-bottom water heavy oil reservoirs as described in claim 1, characterized in that, Water-soluble resin 5%-20%, flexible polymer 0.5%-4%, coagulant 0.05%-0.2%, suspending agent 0.1%-1%, balance water.

3. The water-controlling and plugging agent for edge-bottom water-rich heavy oil reservoirs as described in claim 1, characterized in that, It also includes 0.05%-2% oxygen scavenger, preferably 0.1%-0.5%.

4. The water-controlling and plugging agent for edge-bottom water heavy oil reservoirs as described in claim 1, characterized in that, It also includes 0.1%-5% toughening agent, preferably 0.5%-5%.

5. The water-controlling and plugging agent for edge-bottom water-rich heavy oil reservoirs as described in claim 1, characterized in that, The water-soluble resin is one or more of water-soluble phenolic resin, water-soluble urea-formaldehyde resin, and water-soluble furan resin, preferably water-soluble phenolic resin, and / or The viscosity-average molecular weight of the water-soluble resin is 100,000 to 2,000,000.

6. The water-controlling and plugging agent for edge-bottom water heavy oil reservoirs as described in claim 1, characterized in that, The flexible polymer is one or more of polyvinylpyrrolidone, acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate copolymer, acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, preferably acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer, and / or The flexible polymer has a viscosity-average molecular weight of 2 million to 20 million, preferably 2 million to 4 million, and / or The acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate copolymer is copolymerized from acrylamide monomer and sodium 2-acrylamido-2-methylpropanesulfonate monomer in an equimolar ratio, and / or The acrylamide / sodium 2-acrylamido-2-methylpropanesulfonate / N-vinylpyrrolidone copolymer is copolymerized from acrylamide monomer, sodium 2-acrylamido-2-methylpropanesulfonate monomer, and N-vinylpyrrolidone monomer in an equimolar ratio.

7. The water-controlling and plugging agent for edge-bottom water heavy oil reservoirs as described in claim 1, characterized in that, The coagulant is one or more of sodium chloride, calcium chloride, magnesium chloride, and aluminum chloride, preferably sodium chloride, and / or The oxygen scavenger is one or more of thiourea, sodium sulfite, and urea, preferably thiourea, and / or The toughening agent is one or more of fly ash, slag, ultrafine cement, and cellulose, preferably cellulose.

8. The water-controlling and plugging agent for edge-bottom water-laden oil reservoirs as described in claim 7, characterized in that, The molecular weight of the cellulose is 50,000-250,000, preferably 50,000-80,000, and / or The average particle size of the fly ash, slag, and ultrafine cement is 5-100 μm.

9. The water-controlling and plugging agent for edge-bottom water heavy oil reservoirs as described in claim 1, characterized in that, The suspending agent is one or more of the following: polyoxyethylene sorbitan fatty acid ester, sodium lauryl sulfate, dodecylphenol polyoxyethylene ether, and cocamidopropyl hydroxysulfonate betaine.

10. A method for preparing the water-controlling and plugging agent for edge-bottom water heavy oil reservoirs according to any one of claims 1-9, characterized in that, The steps are as follows: (1) Pour the amount of water in the formula into the reaction vessel, and add the amount of water-soluble resin, the amount of suspending agent, the amount of oxygen scavenger and the amount of toughening agent in the formula in sequence. Stir for at least 20 minutes to obtain the first mixture. (2) Add the formulated amount of flexible polymer to the first mixture and stir at room temperature for at least 4 hours until completely dissolved to obtain the second mixture; (3) Add the formula amount of coagulant to the second mixture and continue stirring for at least 30 minutes to obtain the water control and plugging agent for the heavy oil reservoir with edge and bottom water.

11. A water-controlling and plugging agent for heavy oil reservoirs with edge and bottom water, characterized in that, It is prepared by the preparation method described in claim 10.

12. The application of the water-controlling and plugging agent of any one of claims 1-9 and 11 in the exploitation of heavy oil reservoirs with edge and bottom water as a water-controlling and plugging agent.

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