Temperature response type water shutoff agent as well as preparation method and use method thereof

Abstract

The invention belongs to the technical field of petroleum and natural gas development, and particularly discloses a temperature response type water shutoff agent as well as a preparation method and a use method thereof. The temperature response type water plugging agent is composed of a main agent, an auxiliary agent and a conditioning agent, the mass ratio of the main agent to the auxiliary agent is (3-5): 1, the adding amount of the conditioning agent is 2%-8% of the mass of the main agent, and the main agent comprises, by mass, 20%-30% of triallyl isocyanurate, 20%-40% of chloropropene, 1%-5% of anhydrous sodium carbonate and the balance solvent; the auxiliary agent is prepared from the following components in percentage by mass: 40 to 70 percent of acetic acid-2-chloropropene ester, 20 to 30 percent of polyethylene glycol and 10 to 40 percent of p-xylene; the regulator is a hydrogen peroxide solution with the concentration of 30%. The temperature response type water plugging agent is in a liquid state at normal temperature, can be easily injected into an oil and gas reservoir, is stimulated by high temperature of the reservoir after entering the reservoir, generates phase change and is changed into a solid state from the liquid state, so that the water plugging effect is achieved; the plugging agent has a good plugging effect for a long time; the higher the temperature is, the easier the phase change is, and the better the use effect is.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and natural gas development, and specifically relates to a temperature-responsive water plugging agent and a preparation method and a use method thereof. Background Art

[0002] In order to replenish the energy of the oil layer and displace crude oil, oil reservoirs are often developed by water injection. However, due to the heterogeneity of the oil layer, the injected water preferentially flows along the high permeability flow channel (also known as the "dominant flow channel"), resulting in a series of problems such as reduced water drive swept volume, reduced oil recovery efficiency, and premature water breakthrough in the oil well. It is inevitable that the water content of the oil well will remain high when developing oil reservoirs with water injection, especially in advanced water injection oil reservoirs where the oil wells break water early and the water content is high. Therefore, water plugging in oil wells has always been a key research content in the development of oil reservoirs with water injection.

[0003] The disclosed “A well-washing foam water-plugging agent and its preparation method (202010977976.X)” discloses a well-washing foam water-plugging agent, the components and proportions of the foam water-plugging agent are as follows by weight percentage: 0.2-0.8% foaming agent, 0.2%-0.6% foam stabilizer, 0.2-0.8% thickener, and the rest water; its preparation method is: according to the corresponding proportion, the foaming agent, the foam stabilizer, and the thickener are added to the water, and mixed thoroughly to obtain the well-washing foam water-plugging agent; the disclosed “A water-plugging agent, its preparation method and application (202010810572.1)” discloses a water-plugging agent and its preparation method, which is characterized by: according to mass percentage, 65-90% of oil-soluble resin, 2-5% of Industrial gelatin, 3-25% plasticizer, 2-4% softening point regulator, 0.5-1.0% cross-linking agent, 0.3% dispersant. The raw materials of the water plugging agent do not contain inorganic solid particles, which reduces the damage to the formation after the temporary water plugging is dissolved; the disclosed "Selective water plugging agent made from oil residue or oily sludge and its preparation method (201510520553.4)" discloses a selective water plugging agent made from oil residue or oily sludge. The raw materials for preparing the selective water plugging agent include the following components: 20%-40% oil residue or oily sludge, 5%-20% asphalt, 0.2%-1% zwitterionic surfactant, 0.5%-2% hyperdispersant, 1%-10% solid particles and the remainder of water.

[0004] Existing water plugging agents can achieve good water plugging effects to a certain extent, but the following problems still exist: (1) The plugging effect is poor (a water plugging agent and its preparation method and application-202010810572.1, insufficient pressure resistance under long-term conditions); (2) The operating temperature is limited (a well washing foam water plugging agent and its preparation method-202010977976.X, the optimal temperature is 70°C, and the current oil and gas reservoir temperature is generally above 100°C); (3) Difficult to inject (a selective water plugging agent made from oil residue or oil-containing sludge and its preparation method-201510520553.4, oil residue and oil-containing sludge are solid wastes and are difficult to inject into the formation). Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a temperature-responsive water plugging agent, which is liquid at room temperature and can be easily injected into oil and gas reservoirs. After entering the reservoir, it is stimulated by the high temperature of the reservoir and undergoes a phase change from liquid to solid, thereby achieving a water plugging effect. The agent has a good plugging effect over a long period of time. The higher the temperature, the easier it is to change phases, and the better the use effect.

[0006] According to a first aspect of the present invention, a temperature-responsive water plugging agent is provided, which is composed of a main agent, an auxiliary agent, and a regulator, wherein the mass ratio of the main agent to the auxiliary agent is 3-5:1, and the amount of the regulator is 2%-8% of the mass of the main agent, wherein:

[0007] The main agent comprises, by mass percentage, 20%-30% of triallyl isocyanurate, 20%-40% of allyl chloride, 1%-5% of anhydrous sodium carbonate, and the rest is solvent;

[0008] The auxiliary agent comprises, by mass percentage, 40%-70% of 2-chloropropylene acetate, 20%-30% of polyethylene glycol, and 10%-40% of p-xylene;

[0009] The regulator is a 30% concentration of hydrogen peroxide solution.

[0010] According to some embodiments of the present invention, the amount of the conditioning agent added is determined based on the reservoir temperature.

[0011] According to some embodiments of the present invention, the amount of the conditioning agent added decreases as the reservoir temperature increases.

[0012] According to some embodiments of the present invention, when the reservoir temperature is greater than or equal to 140°C, the amount of the regulator added is 2% of the mass of the main agent; when the reservoir temperature is greater than or equal to 120°C and less than 140°C, the amount of the regulator added is 4% of the mass of the main agent; when the reservoir temperature is greater than or equal to 100°C and less than 120°C, the amount of the regulator added is 6% of the mass of the main agent; when the reservoir temperature is less than 100°C, the amount of the regulator added is 8% of the mass of the main agent.

[0013] According to some embodiments of the present invention, the main agent, the auxiliary agent, and the regulating agent are stored separately and are simultaneously injected into the oil and gas reservoir using different pumps when used on site.

[0014] According to some embodiments of the present invention, the main agent, the auxiliary agent, and the regulator are injected into the oil and gas reservoir through an oil and gas well and are fully mixed in the oil and gas well.

[0015] According to some embodiments of the present invention, the solvent is DMF.

[0016] According to a second aspect of the present invention, there is provided a method for preparing the temperature-responsive water plugging agent, comprising the following steps:

[0017] Synthesis of the main agent: dissolving triallyl isocyanurate in a solvent, adding pre-dried and ground anhydrous sodium carbonate, stirring and heating, then dropping allyl chloride, and reacting at a constant temperature for a period of time to obtain the main agent;

[0018] Synthetic auxiliary agent: fully stirring and dissolving 2-chloropropylene acetate, polyethylene glycol and p-xylene at 80° C. to obtain the auxiliary agent;

[0019] The main agent, the auxiliary agent and the regulator are stored separately.

[0020] According to some embodiments of the present invention, the main agent is synthesized by the following method: triallyl isocyanurate and a solvent are mixed, and the mixture is stirred and dissolved at 100° C. for 1.5 hours to obtain a light yellow solution; pre-dried and ground anhydrous sodium carbonate is then added, and the mixture is stirred and heated; allyl chloride is slowly added dropwise, and the addition time is controlled to be about 2 hours. At this time, the temperature is raised to 120° C., and after the addition is completed, the mixture is reacted at a constant temperature for 1.5 hours to obtain the main agent.

[0021] According to a third aspect of the present invention, there is provided a method for using the temperature-responsive water plugging agent, comprising:

[0022] When used on site, different pumps are used to simultaneously inject the main agent, auxiliary agent, and regulator that are stored separately into the oil and gas reservoir.

[0023] Due to the adoption of the above technical solution, the present invention has the following beneficial effects compared with the prior art:

[0024] The temperature-responsive water plugging agent provided by the present invention is injected into the reservoir in liquid form, has the characteristics of easy injection, reacts into the solid state at the reservoir temperature after entering the reservoir, has high plugging pressure and good water plugging effect, can be used in reservoirs with a temperature higher than 140°C, and has good temperature resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a production data chart of the BX oil well after water plugging construction using the temperature-responsive water plugging agent provided by the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] According to the first aspect of the present invention, a temperature-responsive water plugging agent is provided, which is composed of a main agent, an auxiliary agent, and a regulator. The mass ratio of the main agent to the auxiliary agent is 3-5:1, and the amount of the regulator is 2%-8% of the mass of the main agent, wherein: the main agent includes, by mass percentage: triallyl isocyanurate 20%-30%, allyl chloride 20%-40%, anhydrous sodium carbonate 1%-5%, and the rest is a solvent; the auxiliary agent includes, by mass percentage: 2-chloropropene acetate 40%-70%, polyethylene glycol 20%-30%, p-xylene 10%-40%; the regulator is a 30% concentration of hydrogen peroxide solution. In some embodiments, the solvent is DMF.

[0028] In the main agent, triallyl isocyanurate is the building unit, allyl chloride is the functional unit, and anhydrous sodium carbonate is the cosolvent. In the process, the functional unit allyl chloride is added to the supramolecular building unit to modify the building unit to obtain the main agent; 2-chloropropene acetate, polyethylene glycol, and p-xylene are used as organic synthetic raw materials to prepare the auxiliary agent, and the role of the auxiliary agent is to adjust the temperature response characteristics of the main agent; after the main agent, auxiliary agent, and regulator are mixed, the functional unit is changed, the molecular structure is modified, and the molecular function is better. Among them, the role of the regulator is to adjust the phase change time of the main agent.

[0029] The temperature-responsive water-plugging agent provided by the present invention is in liquid state at room temperature and can be easily injected into oil and gas reservoirs. After entering the reservoirs, it is stimulated by the high temperature of the reservoirs and undergoes a phase change from liquid to solid state, thereby achieving a water-plugging effect. It has a good plugging effect over a long period of time. The higher the temperature, the easier it is to change phases, and the better the use effect.

[0030] In some embodiments, the amount of the regulator is determined based on the reservoir temperature. Specifically, the amount of the regulator decreases as the reservoir temperature increases. Preferably, when the reservoir temperature is greater than or equal to 140°C, the amount of the regulator is 2% of the mass of the main agent; when the reservoir temperature is greater than or equal to 120°C and less than 140°C, the amount of the regulator is 4% of the mass of the main agent; when the reservoir temperature is greater than or equal to 100°C and less than 120°C, the amount of the regulator is 6% of the mass of the main agent; when the reservoir temperature is less than 100°C, the amount of the regulator is 8% of the mass of the main agent.

[0031] The temperature-responsive water plugging agent provided by the present invention has a main agent, an auxiliary agent, and a regulating agent stored separately, and is simultaneously injected into the oil and gas reservoir using different pumps when used on site. The main agent, the auxiliary agent, and the regulating agent are injected into the oil and gas reservoir through an oil and gas well, are fully mixed in the oil and gas well, and after entering the reservoir, the mixture is transformed from a liquid state to a solid state under the stimulation of the formation temperature, thereby achieving the purpose of water plugging.

[0032] According to a second aspect of the present invention, there is provided a method for preparing the above-mentioned temperature-responsive water plugging agent, comprising the following steps: synthesizing a main agent: dissolving triallyl isocyanurate in a solvent, adding pre-dried and ground anhydrous sodium carbonate, stirring and heating, then dripping allyl chloride, and reacting at a constant temperature for a period of time to obtain a main agent; synthesizing an auxiliary agent: fully stirring and dissolving 2-chloropropylene acetate, polyethylene glycol, and p-xylene at 80°C to obtain an auxiliary agent; and storing the main agent, the auxiliary agent, and the regulator separately.

[0033] In the present invention, the synthesis process of the main agent is a supramolecular polymerization reaction process, and the synthesis process of the auxiliary agent is a macromolecular polymerization reaction process.

[0034] In some embodiments, the main agent is synthesized by the following method: a 500mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a constant pressure dropping funnel is placed in a heating mantle, triallyl isocyanurate and DMF are added, and stirred and dissolved at 100°C for 1.5 hours to obtain a light yellow solution; then pre-dried and ground anhydrous sodium carbonate is added, stirred and heated; allyl chloride is slowly added dropwise, and the addition time is controlled to about 2 hours. At this time, the temperature is raised to 120°C. After the addition is completed, the reaction is carried out at a constant temperature for 1.5 hours to obtain the main agent.

[0035] According to a third aspect of the present invention, a method for using the temperature-responsive water plugging agent is provided, comprising: injecting separately stored main agent, auxiliary agent, and regulating agent into the oil and gas reservoir simultaneously using different pumps when used on site.

[0036] The present invention is described in detail below through specific examples. In the following examples, unless otherwise specified, all the raw materials used are commercially available.

[0037] Example 1

[0038] A 500mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a constant pressure dropping funnel was placed in a heating mantle, 40g of triallyl isocyanurate and 78g of DMF were added, and the mixture was stirred and dissolved at 100°C for 1.5h to obtain a light yellow solution; 2g of pre-dried and ground anhydrous sodium carbonate was added, and the mixture was stirred and heated; 80g of allyl chloride was slowly added dropwise, and the addition time was controlled to be about 2h. At this time, the temperature was raised to 120°C. After the addition was completed, the mixture was reacted at a constant temperature for 1.5h to obtain the main agent.

[0039] Add 20 g of 2-chloropropylene acetate, 10 g of polyethylene glycol, and 20 g of p-xylene into a beaker, stir and dissolve them at 80°C to obtain an auxiliary agent.

[0040] The main agent, auxiliary agent and regulator are stored separately and injected into the oil and gas reservoir simultaneously with different pumps when used on site.

[0041] In this embodiment, the mass ratio of the main agent to the auxiliary agent is 4:1; the main agent is calculated by mass percentage: 20% of triallyl isocyanurate, 40% of allyl chloride, 1% of anhydrous sodium carbonate, and 39% of solvent; the auxiliary agent is calculated by mass percentage: 40% of 2-chloroallyl acetate, 20% of polyethylene glycol, and 40% of p-xylene.

[0042] Example 2

[0043] A 500mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a constant pressure dropping funnel was placed in a heating mantle, 50g of triallyl isocyanurate and 84g of DMF were added, and the mixture was stirred and dissolved at 100°C for 1.5h to obtain a light yellow solution; 6g of pre-dried and ground anhydrous sodium carbonate was added, and the mixture was stirred and heated; 60g of allyl chloride was slowly added dropwise, and the addition time was controlled to be about 2h. At this time, the temperature was raised to 120°C. After the addition was completed, the mixture was reacted at a constant temperature for 1.5h to obtain the main agent.

[0044] Add 35 g of 2-chloropropylene acetate, 10 g of polyethylene glycol, and 5 g of p-xylene into a beaker, stir and dissolve them at 80°C to obtain an auxiliary agent.

[0045] The main agent, auxiliary agent and regulator are stored separately and injected into the oil and gas reservoir simultaneously with different pumps when used on site.

[0046] In this embodiment, the mass ratio of the main agent to the auxiliary agent is 4:1; the main agent is calculated by mass percentage: 25% of triallyl isocyanurate, 30% of allyl chloride, 3% of anhydrous sodium carbonate, and 42% of solvent; the auxiliary agent is calculated by mass percentage: 70% of 2-chloroallyl acetate, 20% of polyethylene glycol, and 10% of p-xylene.

[0047] Example 3

[0048] A 500mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a constant pressure dropping funnel was placed in a heating mantle, 60g of triallyl isocyanurate and 50g of DMF were added, and the mixture was stirred and dissolved at 100°C for 1.5h to obtain a light yellow solution; 10g of pre-dried and ground anhydrous sodium carbonate was added, and the mixture was stirred and heated; 80g of allyl chloride was slowly added dropwise, and the addition time was controlled to be about 2h. At this time, the temperature was raised to 120°C. After the addition was completed, the mixture was reacted at a constant temperature for 1.5h to obtain the main agent.

[0049] The synthesis method of the auxiliary agent is as follows: 20g of 2-chloropropylene acetate, 15g of polyethylene glycol and 15g of p-xylene are added into a beaker, and the mixture is fully stirred and dissolved at 80°C to obtain the auxiliary agent.

[0050] The main agent, auxiliary agent and regulator are stored separately and injected into the oil and gas reservoir simultaneously with different pumps when used on site.

[0051] In this embodiment, the mass ratio of the main agent to the auxiliary agent is 4:1; the main agent is calculated by mass percentage: 30% of triallyl isocyanurate, 40% of allyl chloride, 5% of anhydrous sodium carbonate, and 25% of solvent; the auxiliary agent is calculated by mass percentage: 40% of 2-chloroallyl acetate, 30% of polyethylene glycol, and 30% of p-xylene.

[0052] Example 4

[0053] A 500mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a constant pressure dropping funnel was placed in a heating mantle, 60g of triallyl isocyanurate and 90g of DMF were added, and the mixture was stirred and dissolved at 100°C for 1.5h to obtain a light yellow solution; 10g of pre-dried and ground anhydrous sodium carbonate was added, and the mixture was stirred and heated; 40g of allyl chloride was slowly added dropwise, and the addition time was controlled to be about 2h. At this time, the temperature was raised to 120°C. After the addition was completed, the mixture was reacted at a constant temperature for 1.5h to obtain the main agent.

[0054] The synthesis method of the auxiliary agent is as follows: 20g of 2-chloropropylene acetate, 15g of polyethylene glycol and 15g of p-xylene are added into a beaker, and the mixture is fully stirred and dissolved at 80°C to obtain the auxiliary agent.

[0055] The main agent, auxiliary agent and regulator are stored separately and injected into the oil and gas reservoir simultaneously with different pumps when used on site.

[0056] In this embodiment, the mass ratio of the main agent to the auxiliary agent is 4:1; the main agent is calculated by mass percentage: 30% of triallyl isocyanurate, 20% of allyl chloride, 5% of anhydrous sodium carbonate, and 45% of solvent; the auxiliary agent is calculated by mass percentage: 40% of 2-chloroallyl acetate, 30% of polyethylene glycol, and 30% of p-xylene.

[0057] Example 5

[0058] A 500mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a constant pressure dropping funnel was placed in a heating mantle, 30g of triallyl isocyanurate and 58.5g of DMF were added, and the mixture was stirred and dissolved at 100°C for 1.5h to obtain a light yellow solution; 1.5g of anhydrous sodium carbonate that had been dried and ground in advance was added, and the mixture was stirred and heated; 60g of allyl chloride was slowly added dropwise, and the addition time was controlled to be about 2h. At this time, the temperature was raised to 120°C. After the addition was completed, the mixture was reacted at a constant temperature for 1.5h to obtain the main agent.

[0059] Add 20 g of 2-chloropropylene acetate, 10 g of polyethylene glycol, and 20 g of p-xylene into a beaker, stir and dissolve them at 80°C to obtain an auxiliary agent.

[0060] The main agent, auxiliary agent and regulator are stored separately and injected into the oil and gas reservoir simultaneously with different pumps when used on site.

[0061] In this embodiment, the mass ratio of the main agent to the auxiliary agent is 3:1; the main agent is calculated by mass percentage: 20% of triallyl isocyanurate, 40% of allyl chloride, 1% of anhydrous sodium carbonate, and 39% of solvent; the auxiliary agent is calculated by mass percentage: 40% of 2-chloroallyl acetate, 20% of polyethylene glycol, and 40% of p-xylene.

[0062] Example 6

[0063] A 500mL four-necked flask equipped with a stirrer, a condenser, a thermometer and a constant pressure dropping funnel was placed in a heating mantle, 50g of triallyl isocyanurate and 97.5g of DMF were added, and the mixture was stirred and dissolved at 100°C for 1.5h to obtain a light yellow solution; 2.5g of anhydrous sodium carbonate that had been dried and ground in advance was added, and the mixture was stirred and heated; 100g of allyl chloride was slowly added dropwise, and the addition time was controlled to be about 2h. At this time, the temperature was raised to 120°C. After the addition was completed, the mixture was reacted at a constant temperature for 1.5h to obtain the main agent.

[0064] Add 20 g of 2-chloropropylene acetate, 10 g of polyethylene glycol, and 20 g of p-xylene into a beaker, stir and dissolve them at 80°C to obtain an auxiliary agent.

[0065] The main agent, auxiliary agent and regulator are stored separately and injected into the oil and gas reservoir simultaneously with different pumps when used on site.

[0066] In this embodiment, the mass ratio of the main agent to the auxiliary agent is 5:1; the main agent is calculated by mass percentage: 20% of triallyl isocyanurate, 40% of allyl chloride, 1% of anhydrous sodium carbonate, and 39% of solvent; the auxiliary agent is calculated by mass percentage: 40% of 2-chloroallyl acetate, 20% of polyethylene glycol, and 40% of p-xylene.

[0067] Performance Test:

[0068] Taking the water plugging agent prepared in Example 1 as an example, the plugging pressure and temperature resistance performance tests were carried out. Since the main agent, auxiliary agent and regulating agent were stored separately, they were injected into the oil and gas reservoir at the same time with different pumps when used on site. When the performance was evaluated in the laboratory, the main agent, auxiliary agent and regulating agent were directly mixed in a certain proportion, and then the performance test was carried out at the experimental temperature.

[0069] (1) Plugging pressure

[0070] 100g of the main agent prepared in Example 1, 25g of the auxiliary agent, and 4g of 30% hydrogen peroxide were taken for plugging ability test at 130°C. The test method is shown in Section 3.1 of the academic paper published by this team, "Zhao Liqiang et al. Application of liquid diversion technology in XS injection and production wells of Suqiao gas storage [J]. Petroleum Drilling and Production Technology, 2020, 42(6): 762-766". The plugging pressure test results are shown in the following table:

[0071] Table 1 Plugging performance test

[0072] Pipeline length, m 0.3 0.75 1.5 Plugging pressure, MPa 5 8.5 17.2

[0073] The plugging pressure test results show that the water plugging agent can provide a plugging pressure of more than 17MPa, and the larger the plugging volume, the greater the plugging pressure, which can effectively achieve water plugging.

[0074] (2) Heat resistance

[0075] Take 100g of the main agent and 25g of the auxiliary agent prepared in Example 1, and take 2g, 4g, 6g, and 8g of 30% hydrogen peroxide respectively for temperature resistance test. The test temperatures are 150°C, 130°C, 110°C, and 90°C, respectively. The length of the blocked pipeline is 0.75m. The test method is shown in Section 3.1 of the academic paper published by this team, "Zhao Liqiang et al. Application of liquid diversion technology in XS injection and production wells of Suqiao gas storage [J]. Petroleum Drilling and Production Technology, 2020, 42(6): 762-766". The results of the temperature resistance test are shown in the following table:

[0076] Table 2 Temperature resistance test

[0077] Temperature, °C 150 130 110 90 Plugging pressure, MPa 8.9 9.7 10.6 12.1

[0078] The plugging pressure test results show that under temperatures as high as 150°C, the water plugging agent can still provide a plugging pressure of 8.9MPa, which is fully capable of meeting the pressure required for water plugging.

[0079] On-site application effect:

[0080] A water plugging test was carried out on site at the BX oil well in a block of Changqing Oilfield. The initial liquid production of the BX oil well was 5.1m 3 / d, oil production 2.5m3 / d, water output 2.6m 3 / d, with a comprehensive water content of 50.98%. Aiming at the high water content of the produced fluid of BX oil well, water plugging construction was carried out using water plugging agent, injected using 73.0mm oil pipe. The water plugging construction pumping procedure is shown in the table below.

[0081] Table 3BX Oil Well Water Plugging Construction Pumping Program

[0082] fluid <![CDATA[Liquid volume, m 3 > <![CDATA[Displacement, m 3 / min]]> Remark Pre-fluid 27.0 3.0～4.0 Active water fracturing fluid Water plugging agent 12.0 1.5～2.0 / Displacement fluid 25.0 1.5～2.5 Guar fracturing fluid (viscosity 40.0mPa·s)

[0083] After the water plugging agent is used for water plugging, the production data of BX oil well is as follows: Figure 1 As shown in the figure, after the water plugging construction, the cumulative liquid production in 68 days was 311.1m 3 , with a total oil production of 204.5m 3 , cumulative water production 106.6m 3 The average water content is 34.27%, compared with the comprehensive water content of 50.98% before water plugging construction, the effect of reducing water and increasing oil is significant.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention, including the combination of various technical features in any other appropriate manner, these simple variations and combinations should also be regarded as the contents disclosed by the present invention and should be included in the protection scope of the present invention.

Claims

1. A temperature-responsive water plugging agent, characterized in that: The temperature-responsive water plugging agent is composed of a main agent, an auxiliary agent, and a regulator. The mass ratio of the main agent to the auxiliary agent is 3-5:1, and the amount of the regulator is 2%-8% of the mass of the main agent, wherein: The main agent comprises, by mass percentage, 20%-30% of triallyl isocyanurate, 20%-40% of allyl chloride, 1%-5% of anhydrous sodium carbonate, and the rest is solvent; The auxiliary agent comprises, by mass percentage, 40%-70% of 2-chloropropylene acetate, 20%-30% of polyethylene glycol, and 10%-40% of p-xylene; The regulator is a 30% concentration of hydrogen peroxide solution.

2. The temperature-responsive water plugging agent according to claim 1, characterized in that: The amount of the regulator added is determined based on the reservoir temperature.

3. The temperature-responsive water plugging agent according to claim 2, characterized in that: The amount of the regulator added decreases as the reservoir temperature increases.

4. The temperature-responsive water plugging agent according to claim 2 or 3, characterized in that: When the reservoir temperature is greater than or equal to 140°C, the amount of the regulator added is 2% of the mass of the main agent; when the reservoir temperature is greater than or equal to 120°C and less than 140°C, the amount of the regulator added is 4% of the mass of the main agent; when the reservoir temperature is greater than or equal to 100°C and less than 120°C, the amount of the regulator added is 6% of the mass of the main agent; when the reservoir temperature is less than 100°C, the amount of the regulator added is 8% of the mass of the main agent.

5. The temperature-responsive water plugging agent according to claim 1, characterized in that: The main agent, the auxiliary agent and the regulating agent are stored separately and are simultaneously injected into the oil and gas reservoir using different pumps when used on site.

6. The temperature-responsive water plugging agent according to claim 5, characterized in that: The main agent, the auxiliary agent and the regulator are injected into the oil and gas reservoir through the oil and gas well and are fully mixed in the oil and gas well.

7. The temperature-responsive water plugging agent according to claim 1, characterized in that: The solvent is DMF.

8. A method for preparing the temperature-responsive water plugging agent according to any one of claims 1 to 7, comprising the following steps: Synthesis of the main agent: dissolving triallyl isocyanurate in a solvent, adding pre-dried and ground anhydrous sodium carbonate, stirring and heating, then dropping allyl chloride, and reacting at a constant temperature for a period of time to obtain the main agent; Synthetic auxiliary agent: fully stirring and dissolving 2-chloropropylene acetate, polyethylene glycol and p-xylene at 80° C. to obtain the auxiliary agent; The main agent, the auxiliary agent and the regulator are stored separately.

9. The method for preparing the temperature-responsive water plugging agent according to claim 8, characterized in that: The main agent is synthesized in the following manner: triallyl isocyanurate and a solvent are mixed, and the mixture is stirred and dissolved at 100° C. for 1.5 hours to obtain a light yellow solution; pre-dried and ground anhydrous sodium carbonate is then added, and the mixture is stirred and heated; allyl chloride is slowly added dropwise, and the addition time is controlled to be about 2 hours. At this time, the temperature is raised to 120° C., and after the addition is completed, the mixture is reacted at a constant temperature for 1.5 hours to obtain the main agent.

10. A method for using the temperature-responsive water plugging agent according to any one of claims 1 to 7, comprising: When used on site, different pumps are used to simultaneously inject the main agent, auxiliary agent, and regulator that are stored separately into the oil and gas reservoir.

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