A phase permeability adjusting water control and yield increasing agent for heavy oil reservoir and a preparation method thereof

Abstract

This invention belongs to the field of heavy oil reservoir development technology, specifically relating to a water-controlling and production-enhancing agent for heavy oil reservoirs and its preparation method. The water-controlling and production-enhancing agent for heavy oil reservoirs of this invention comprises a polymer as shown in Formula I: wherein R1 is an alkyl group with 10-18 carbon atoms, and R2 is methyl or H. The water-controlling and production-enhancing agent for heavy oil reservoirs prepared by this invention can change the reservoir wettability to a strongly oleophilic state, establish a water phase pressure differential near the wellbore, and block water production points, thereby reducing the water cut of the oil well. Furthermore, the water-controlling and production-enhancing agent of this invention can reduce crude oil viscosity, improve crude oil flowability, and increase crude oil production, thus achieving the goal of reducing water and increasing oil production, providing a new technical means for the efficient development of heavy oil reservoirs.

Description

Technical Field

[0001] This invention belongs to the field of heavy oil reservoir development technology, specifically relating to a phase permeation regulating and water control agent for heavy oil reservoirs and its preparation method. Background Technology

[0002] Horizontal wells are currently the primary development method for heavy oil reservoirs. However, once a water cone forms in a horizontal well, due to the high viscosity ratio of oil to water and the good fluidity of the water phase compared to the poor fluidity of heavy oil, a pressure funnel will form at the water outlet, reducing the driving pressure differential of the oil phase and resulting in high water cut, which is difficult to manage. In recent years, many new products and technologies have emerged for water shut-off in heavy oil horizontal wells, such as organic chromium gels, phenolic resin gels, water glass, and solid particulate plugging agents. While these technologies have shown some effectiveness, they also have limitations, mainly including the following:

[0003] (1) The plugging agent has a variety of components, which can easily form chromatographic separation in the formation. The formation gelation rate is low, and some plugging agents have strict requirements for gelation temperature, resulting in poor water plugging effect.

[0004] (2) Poor selectivity: after the plugging agent enters the oil layer, there are residues in the oil layer. The driving pressure difference of heavy oil is already high. These damages will further increase the driving pressure difference of heavy oil, resulting in a significant decrease in production capacity.

[0005] (3) The amount and strength of the plugging agent also affect the water shut-off effect. If the plugging agent strength is too high, it cannot penetrate into the deep formation, resulting in a significant reduction in permeability in the near-wellbore zone. If the plugging agent strength is too low, it cannot effectively seal the water outlet.

[0006] Invention patent CN202211298479.2 discloses an oilfield relative permeability regulator and its preparation method. The invention consists of surfactant, synergist, emulsifier and solvent. The synergist is cellulose obtained by acid hydrolysis of straw. It does not have oil-soluble properties. After entering the oil layer, it is easy to block the oil layer. It does not have selective blocking properties and will cause permanent damage to the reservoir permeability.

[0007] CN202311168958.7 discloses an amphiphilic carbon dot phase permeability modifier for water-controlled fracturing in high-temperature, high-salinity gas reservoirs. The phase permeability modifier is a mixture of component A and brine, with component A having a concentration of 0.08–0.6 g / L. Component A is an amphiphilic carbon dot, or a mixture of amphiphilic carbon dot and surfactant in any proportion. The amphiphilic carbon dot is prepared by a hydrothermal method using guar gum, oxidizing acid, and alkylamine as raw materials. The amphiphilic carbon dot of this invention has a small size (1-10 nm) and exhibits good surface activity and wetting properties even in high-temperature and high-salinity environments. It can adjust hydrophobic surfaces to a hydrophilic state, reducing aqueous phase permeability and achieving water-controlled fracturing and increased production in tight gas reservoirs. The main function of this phase permeability modifier is to increase the aqueous phase permeability of tight oil layers; it cannot be used for water control in heavy oil reservoirs.

[0008] CN102732242A discloses an acidification pretreatment solution with percolation regulation function. The reactants and their contents (by mass parts): acrylic acid 5-15 parts; acrylate 2-8 parts; acrylamide 1-8 parts; coupling agent KH570 2-5 parts; deionized water balance. The preparation process is as follows: a) Add the monomers acrylic acid, acrylate, acrylamide, coupling agent KH570, and deionized water sequentially to a reactor and stir until homogeneous; b) Heat to 90℃ and maintain the temperature for 2 hours; c) Purge with nitrogen and stir for 30 minutes to remove oxygen from the solution; d) Add 0.2%-0.8% (by mass) of a solid initiator and initiate the polymerization reaction under normal pressure for 7-9 hours to obtain the target product with a molecular weight of 6.5-7 million. It is mainly used for acidification and water control.

[0009] CN102002348A discloses a phase permeability regulator, the components and proportions of which are: 5-15 parts by weight of acrylic acid, 2-8 parts by weight of propylene, 1-8 parts by weight of sulfonated propylene, and the balance being deionized water. It is mainly used for sand control and water management.

[0010] Based on the above, there is still a need for selective phase permeability regulating and water control agents that can be effectively used in heavy oil reservoirs and have good plugging effects. Summary of the Invention

[0011] To address the aforementioned problems, the main objective of this invention is to provide a water-controlling and production-enhancing agent for heavy oil reservoirs and its preparation method. The water-controlling and production-enhancing agent for heavy oil reservoirs prepared by this invention can alter reservoir wettability to a strongly oleophilic state, establish a water-phase pressure differential near the wellbore, and block water-producing points, thereby reducing the water cut of the oil well. Furthermore, it can reduce crude oil viscosity, improve crude oil flowability, and increase crude oil production, thus achieving the goal of reducing water and increasing oil production, providing a new technical means for the efficient development of heavy oil reservoirs.

[0012] To achieve the above objectives, the present invention adopts the following technical solution:

[0013] In a first aspect, the present invention provides a phase permeation regulating and water control agent for heavy oil reservoirs, comprising a polymer of formula I:

[0014]

[0015] Wherein, R1 is an alkyl group with 10-18 carbon atoms, R2 is a methyl group or H, and a, b, c are the degrees of polymerization.

[0016] The polymer shown in Formula I of this invention can effectively prevent the re-accumulation of macromolecular substances in heavy oil to form gums and asphaltenes, and has a good viscosity-reducing effect.

[0017] Furthermore, the heavy oil reservoir phase permeation regulating and water control production enhancer is composed of the following raw materials by weight: 30-60 parts of the polymer shown in Formula I, 30-60 parts of organic solvent, and 3-15 parts of nanomaterials.

[0018] Furthermore, the organic solvent is one or more of 200# solvent oil, C9 aromatic hydrocarbons, D80 solvent oil, and D100 solvent oil.

[0019] Furthermore, the organic solvent is a mixture of D80 solvent oil and D100 solvent oil.

[0020] Furthermore, the volume ratio of D80 solvent oil to D100 solvent oil is 1-3:1-2.

[0021] The organic solvent used in this invention has a high flash point, is non-flammable and non-explosive, effectively ensuring the safety of on-site construction. Furthermore, the organic solvent described in this invention can disperse the asphaltenes in heavy oil into smaller molecules, reducing the viscosity of the heavy oil.

[0022] Furthermore, the nanomaterial is one or more of nano-silica, nano-titanium dioxide, nano-molybdenum disulfide, and nano-zinc sulfide.

[0023] The nanomaterials in the heavy oil reservoir water control and production enhancement agent of this invention can form an adsorption film on the reservoir surface in combination with other components, which improves the reservoir wettability by being strongly oleophilic, increases the water pressure difference, and increases the water pressure, thereby achieving the purpose of reducing water cut.

[0024] Further, the polymer shown in Formula I is prepared by the following method: by weight, 50-70 parts of D80 solvent oil, 8-20 parts of alkyl acrylate or its derivative, 5-15 parts of divinylbenzene, 5-20 parts of vinyl acetate, and 0.1-0.2 parts of azobisisobutyronitrile.

[0025] Add alkyl acrylate or its derivative, divinylbenzene and vinyl acetate sequentially to D80 solvent oil, heat to 50℃~80℃, stir until completely dissolved, add azobisisobutyronitrile in an inert gas environment, react for 4~10h, and then separate and purify to obtain the product.

[0026] Further, the alkyl acrylate is one or more of tetradecyl acrylate, hexadecyl acrylate, octadecyl acrylate, tetradecyl methacrylate, hexadecyl methacrylate, and octadecyl methacrylate.

[0027] In a second aspect, the present invention provides a method for preparing a water-controlling and production-enhancing agent for heavy oil reservoirs, comprising the following steps:

[0028] (1) Weigh out 50-70 parts of D80 solvent oil, 8-20 parts of alkyl acrylate or its derivatives, 5-15 parts of divinylbenzene, 5-20 parts of vinyl acetate, and 0.1-0.2 parts of azobisisobutyronitrile by weight.

[0029] Alkyl acrylate or its derivatives, divinylbenzene, and vinyl acetate were added sequentially to D80 solvent oil. The mixture was heated to 50°C–80°C and stirred until completely dissolved. Azobisisobutyronitrile (AIBN) was then added under an inert gas atmosphere, and the reaction was carried out for 4–10 hours. After separation and purification, the polymer shown in Formula I was obtained.

[0030]

[0031] Wherein, R1 is an alkyl group having 10-18 carbon atoms, and R2 is a methyl group or H;

[0032] (2) Weigh 30-60 parts of the polymer shown in Formula I, 30-60 parts of the organic solvent, and 3-15 parts of the nanomaterials by weight.

[0033] Add an organic solvent to the reactor, heat to 50℃~80℃, start stirring, control the speed to 500r~2000r / min, add the polymer shown in Formula I, stir until the polymer is completely dissolved, add nanomaterials, and continue stirring for 1~3h to obtain the product.

[0034] Furthermore, the organic solvent is one or more selected from 200# solvent oil, C9 aromatic hydrocarbons, D80 solvent oil, and D100 solvent oil;

[0035] More preferably, the nanomaterial is one or more of nano-silica, nano-titanium dioxide, nano-molybdenum disulfide, and nano-zinc sulfide.

[0036] In a third aspect, the present invention provides a relative permeability regulating and water-controlling agent for heavy oil reservoirs as described in the first aspect above, and the application of the relative permeability regulating and water-controlling agent prepared by the method described in the second aspect above in increasing production in heavy oil reservoirs.

[0037] Furthermore, the heavy oil reservoir is simultaneously treated with a relative permeability regulating and water-controlling production-enhancing agent and nitrogen gas during heavy oil reservoir displacement.

[0038] Compared with the prior art, the present invention has the following technical advantages:

[0039] 1. The phase permeability regulating and water control production enhancer for heavy oil reservoirs described in this invention has a low initial viscosity and good injectability. After entering the formation, due to its low viscosity, it preferentially enters the water outlet point, exhibiting good selectivity. It also adjusts the reservoir wettability to oil wettability, forcibly converting the water phase channel into the oil phase channel, thereby increasing the water outlet pressure difference and making it difficult to extract water under formation pressure.

[0040] 2. The phase permeability regulating and water control agent for heavy oil reservoirs described in this invention also has a good viscosity reduction effect. After entering the oil layer, it can significantly reduce the viscosity of crude oil, improve the fluidity of crude oil in the reservoir, reduce the oil-water mobility ratio, and significantly increase the production of heavy oil.

[0041] 3. The phase permeability regulating and water-controlling agent for heavy oil reservoirs described in this invention transforms the formation near a limited water outlet point into a strongly oleophilic formation, thereby increasing the water phase outflow pressure difference at the water outlet point. When the pressure difference is established to a certain extent, it becomes the driving pressure difference for the oil phase, thus achieving the effect of reducing water and increasing oil production.

[0042] 4. The water-controlling and production-enhancing agent for heavy oil reservoirs described in this invention has the dual functions of water shut-off and viscosity reduction. It can have a good synergistic effect with nitrogen. By utilizing the water-pressing cone effect of nitrogen, the water-pressing cone near the wellbore is suppressed, allowing the water-controlling and production-enhancing agent to fully contact the formation and crude oil. The combined use of the two can significantly reduce the water cut of heavy oil wells and increase crude oil production. Attached Figure Description

[0043] Figure 1 The infrared spectrum of the polymer described in Example 1 of this invention. Detailed Implementation

[0044] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0045] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, and / or combinations thereof.

[0046] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0047] Example 1

[0048] (1) By weight, add 70 parts of D80 solvent oil, 15 parts of octadecyl methacrylate, 5 parts of divinylbenzene and 10 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 60°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 6 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0049] (2) By weight, add 35 parts of D80 solvent oil and 20 parts of D100 solvent oil to the reactor, heat to 50°C, start stirring, control the speed at 500 r / min, add 40 parts of the polymer prepared in step (1), stir until completely dissolved, add 5 parts of nano molybdenum disulfide, and continue stirring for 3 hours to obtain phase permeation regulating water control and yield increasing agent 1#.

[0050] Example 2

[0051] (1) By weight, add 70 parts of D80 solvent oil, 12 parts of hexadecyl methacrylate, 6 parts of divinylbenzene and 12 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 50°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 4 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0052] (2) By weight, add 40 parts of D80 solvent oil and 20 parts of D100 solvent oil to the reactor, heat to 60°C, start stirring, control the speed to 1000 r / min, add 34 parts of the polymer prepared in step (1), stir until completely dissolved, add 6 parts of nano zinc sulfide, and continue stirring for 2 hours to obtain phase permeation regulating water control and yield increasing agent 2#.

[0053] Example 3

[0054] (1) By weight, add 60 parts of D80 solvent oil, 15 parts of tetradecyl methacrylate, 12 parts of divinylbenzene and 13 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 50°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 10 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0055] (2) By weight, add 45 parts of D80 organic solvent and 15 parts of D100 organic solvent to the reactor, heat to 50°C, start stirring, control the speed at 2000 r / min, add 34 parts of the polymer prepared in step (1), stir until completely dissolved, add 6 parts of nano molybdenum disulfide, and continue stirring for 1 hour to obtain phase permeation regulating water control and yield increasing agent 3#.

[0056] Example 4

[0057] (1) By weight, add 65 parts of D80 solvent oil, 10 parts of octadecyl methacrylate, 4 parts of tetradecyl methacrylate, 10 parts of divinylbenzene and 11 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 70°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 8 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0058] (2) By weight, add 25 parts of D80 solvent oil and 30 parts of D100 solvent oil to the reactor, heat to 50°C, start stirring, control the speed at 1000 r / min, add 35 parts of the polymer prepared in step (1), stir until completely dissolved, add 10 parts of nano zinc sulfide, and continue stirring for 3 hours to obtain phase permeation regulating water control and yield increasing agent 4#.

[0059] Example 5

[0060] (1) By weight, add 68 parts of D80 solvent oil, 8 parts of octadecyl methacrylate, 2 parts of tetradecyl methacrylate, 4 parts of divinylbenzene and 18 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 70°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 5 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0061] (2) By weight, add 25 parts of D80 solvent oil and 25 parts of D100 solvent oil to the reactor, heat to 50°C, start stirring, control the speed at 500 r / min, add 43 parts of the polymer prepared in step (1), stir until completely dissolved, add 3 parts of nano zinc sulfide and 4 parts of nano molybdenum disulfide, and continue stirring for 2 hours to obtain phase permeation regulating water control and yield increasing agent 5#.

[0062] Example 6

[0063] (1) By weight, add 63 parts of D80 solvent oil, 9 parts of hexadecyl methacrylate, 1 part of tetradecyl methacrylate, 9 parts of divinylbenzene and 18 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 80°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 4 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0064] (2) By weight, add 30 parts of D80 solvent oil and 25 parts of D100 solvent oil to the reactor, heat to 50°C, start stirring, control the speed at 500 r / min, add 37 parts of the polymer prepared in step (1), stir until the oil-soluble polymer 5# is completely dissolved, add 4 parts of nano zinc sulfide and 4 parts of nano molybdenum disulfide, and continue stirring for 1 hour to obtain nano phase penetration regulator water control and yield increase agent 6#.

[0065] Example 7

[0066] (1) By weight, add 70 parts of D80 solvent oil, 14 parts of octadecyl acrylate, 6 parts of divinylbenzene and 12 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 50°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 4 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0067] (2) By weight, add 38 parts of D80 solvent oil and 22 parts of D100 solvent oil to the reactor, heat to 60°C, start stirring, control the speed to 1000 r / min, add 34 parts of the polymer prepared in step (1), stir until completely dissolved, add 6 parts of nano zinc sulfide, and continue stirring for 2 hours to obtain phase permeation regulating water control and yield increasing agent 7#.

[0068] Example 8

[0069] (1) By weight, add 70 parts of D80 solvent oil, 8 parts of octadecyl acrylate, 6 parts of hexadecyl methacrylate, 6 parts of divinylbenzene and 12 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 50°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 4 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0070] (2) By weight, add 38 parts of D80 solvent oil and 22 parts of D100 solvent oil to the reactor, heat to 60°C, start stirring, control the speed to 1000 r / min, add 35 parts of the polymer prepared in step (1), stir until completely dissolved, add 5 parts of nano molybdenum disulfide, and continue stirring for 2 hours to obtain phase permeation regulating water control and yield increasing agent 8#.

[0071] Example 9

[0072] (1) By weight, add 70 parts of D80 solvent oil, 8 parts of octadecyl acrylate, 6 parts of hexadecyl methacrylate, 6 parts of divinylbenzene and 12 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 50°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 4 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0073] (2) Add 38 parts of 200# solvent oil to the reactor by weight, heat to 60°C, start stirring, control the speed to 1000 r / min, add 35 parts of the polymer prepared in step (1), stir until completely dissolved, add 5 parts of nano molybdenum disulfide, and continue stirring for 2 hours to obtain phase permeation regulating water control and yield increasing agent 9#.

[0074] Example 10

[0075] (1) By weight, add 70 parts of D80 solvent oil, 8 parts of octadecyl acrylate, 6 parts of hexadecyl methacrylate, 6 parts of divinylbenzene and 12 parts of vinyl acetate to a four-necked flask equipped with a reflux condenser. Heat to 50°C, stir until completely dissolved, purge with nitrogen for 30 min, add the initiator azobisisobutyronitrile, reflux for 4 h, and then place the product in a rotary evaporator to distill off the solvent oil under reduced pressure at 85°C to obtain the polymer shown in Formula I.

[0076] (2) Add 38 parts of C9 aromatic hydrocarbons to the reactor by weight, heat to 60°C, start stirring, control the speed to 1000 r / min, add 35 parts of the polymer prepared in step (1), stir until completely dissolved, add 5 parts of nano molybdenum disulfide, and continue stirring for 2 hours to obtain phase permeation regulating water control and yield increase agent 10#.

[0077] Test case

[0078] The phase permeation regulators, water control agents, and yield enhancers prepared in Examples 1-8 above were subjected to the following performance tests, with commercially available oil-soluble viscosity reducers used as controls:

[0079] (1) Viscosity: using a rheometer at 170s -1 The viscosity of the stock solution of the phase permeation regulating water control and yield-increasing agent prepared in Examples 1-8 was tested at 30°C.

[0080] (2) Oil solubility test: Place the phase permeation regulator and water control agent in a 50mL centrifuge tube, centrifuge at 3000r / min for 15min, pour out the supernatant, place the lower precipitate in a 105℃ oven to dry, then accurately put 2g of precipitate (recorded as m0) into 50g of kerosene, place at 60℃ for 1h, filter, dry and weigh, record as m1, and calculate the oil solubility according to formula (1).

[0081]

[0082] (3) Core contact angle test: The core was cut into 3mm thin slices and cleaned with toluene. Then it was dried at 105℃ for 4h. After cooling, the core was placed in the relative permeability regulating water control and production enhancement agent prepared in Examples 1-8 and the commercially available oil-soluble viscosity reducer. The temperature was raised to 60℃ and placed for 48h. After taking it out and wiping the surface dry, the contact angle was tested using a contact angle measuring instrument after treatment with the relative permeability regulating water control and production enhancement agent described in Examples 1-8 of this invention.

[0083] (4) Viscosity reduction test: The viscosity reduction rate of the phase permeability regulating and water control agent was tested according to the method specified in 6.6.3 of "Q / SH CG0065-2021 Technical Requirements for Heavy Oil Viscosity Reducers for Pipeline Transportation and Wellbore". The crude oil used was 139 blocks of crude oil with a blank viscosity of 8039 mPa·s.

[0084] (5) Selective plugging test

[0085] The selective plugging capability of the relative permeability regulating, water control, and yield-increasing agent prepared in Example 1 was determined using parallel dual-tube core samples:

[0086] ① Select two artificial rock cores with similar permeability;

[0087] ②After displacing one of the cores with simulated formation water at 90℃ until the pressure stabilized, the original water phase permeability K0 was calculated and used as the simulated water layer;

[0088] ③ At 90℃, crude oil was used to drive one of the simulated cores to the bound water saturation level and the oil phase permeability K2 was calculated, which was then used as the simulated oil layer;

[0089] ④ Connect the two artificial cores in parallel, and inject 0.3PV (using the pore volume of the simulated water layer as the actual pore volume) of plugging agent in reverse at a rate of 1mL / min at 60℃, then shut in the well and age for 7 days.

[0090] ⑤ Simulate the water layer by forward water drive at 0.5 mL / min at 90℃ until the pressure stabilizes, calculate the water phase permeability K1 after plugging, and calculate the water phase plugging rate Ew according to formula (2);

[0091] ⑥ Simulate the oil layer by forward oil displacement at 0.5 mL / min at 60℃ until the pressure stabilizes, and obtain the oil phase permeability K3 after plugging. Calculate the oil phase permeability E according to formula (3). o .

[0092]

[0093] Table 1 Basic Properties of Porcelain Infiltration Modifiers

[0094]

[0095]

[0096] The crude oil blank viscosity of Pile 139 was 8039 mPa·s. Commercially available oil-soluble viscosity reducers reduced the viscosity of this oil by 94.6%. The relative permeability regulating and water-controlling production enhancers prepared in Examples 1-8 of this invention reduced the viscosity of this oil by 93.8%–95.7%, which is comparable to that of commercially available oil-soluble viscosity reducers. However, the contact angle of the core treated with the relative permeability regulating and water-controlling production enhancer of this invention was 154.6°–168.3°, while the contact angle of the core treated with the commercially available oil-soluble viscosity reducer was only 117.4°. Therefore, the relative permeability regulating and water-controlling production enhancer of this invention has a stronger wetting and modification ability.

[0097] Table 2. Experimental results of selective plugging with phase permeation modifier.

[0098]

[0099] As can be seen from the test results in Tables 1 and 2, the phase permeability regulating and water control agent of this invention has low viscosity and is easy to inject on-site. Its oil solubility is above 95%, indicating good oil solubility. It achieves a water layer plugging rate of up to 93.42%, while its oil layer plugging rate is only 19.97%, demonstrating good selectivity and making it suitable for selective water plugging in heavy oil reservoirs.

[0100] (6) Evaluation of the synergistic effect between the phase permeation regulator, water control agent, and N2

[0101] Using an integrated displacement device, the effects of commercially available oil-soluble viscosity reducers, the relative permeability regulating and water-controlling production enhancer prepared in Example 1 of this invention, N2, and the combined use of N2 and the relative permeability regulating and water-controlling production enhancer described in Example 1 of this invention on improving the recovery rate and reducing water cut of heavy oil reservoirs were evaluated. The results are shown in Table 3.

[0102] Table 3 Results of the physical model experiment

[0103]

[0104]

[0105] As shown in Table 3, the phase permeation regulating water-controlling and production-enhancing agent of this invention has a good effect on improving oil recovery and reducing crude oil water cut. Its water-drive oil recovery is higher than that of commercially available oil-soluble viscosity reducers, and its water cut reduction performance is significantly better than that of commercially available oil-soluble viscosity reducers. Furthermore, the phase permeation regulating water-controlling and production-enhancing agent of this invention has a synergistic effect with N2; the combined effect of both is significantly better than using either one alone.

[0106] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A phase permeability regulating and water control agent for heavy oil reservoirs, characterized in that, Including the polymer shown in Formula I: Wherein, R1 is an alkyl group with 10-18 carbon atoms, R2 is a methyl group or H, and a, b, c are the degrees of polymerization.

2. The phase permeability regulating and water control agent for heavy oil reservoirs according to claim 1, characterized in that, By weight, it is composed of the following raw materials: 30-60 parts of the polymer shown in Formula I, 30-60 parts of organic solvent, and 3-15 parts of nanomaterials.

3. The phase permeability regulating and water control agent for heavy oil reservoirs according to claim 1 or 2, characterized in that, The polymer shown in Formula I is prepared by the following method: Weigh out 50-70 parts by weight of D80 solvent oil, 8-20 parts of alkyl acrylate or its derivatives, 5-15 parts of divinylbenzene, 5-20 parts of vinyl acetate, and 0.1-0.2 parts of azobisisobutyronitrile. Add alkyl acrylate or its derivative, divinylbenzene and vinyl acetate sequentially to D80 solvent oil, heat to 50℃~80℃, stir until completely dissolved, add azobisisobutyronitrile in an inert gas environment, react for 4~10h, and then separate and purify to obtain the product.

4. The phase permeability regulating and water control agent for heavy oil reservoirs according to claim 2, characterized in that, The organic solvent is one or more of 200# solvent oil, C9 aromatic hydrocarbons, D80 solvent oil, and D100 solvent oil.

5. The phase permeability regulating and water control agent for heavy oil reservoirs according to claim 2, characterized in that, The nanomaterial is one or more of nano-silicon dioxide, nano-titanium dioxide, nano-molybdenum disulfide, and nano-zinc sulfide.

6. The phase permeability regulating and water control agent for heavy oil reservoirs according to claim 3, characterized in that, The alkyl acrylate is one or more of tetradecyl acrylate, hexadecyl acrylate, octadecyl acrylate, tetradecyl methacrylate, hexadecyl methacrylate, and octadecyl methacrylate.

7. The heavy oil reservoir phase-adjusting, water-controlling, and production-enhancing agent according to claim 4, characterized in that, The organic solvent is a mixture of D80 solvent oil and D100 solvent oil.

8. The phase permeability regulating and water control agent for heavy oil reservoirs according to claim 7, characterized in that, The volume ratio of D80 solvent oil to D100 solvent oil is 1-3:1-2.

9. A method for preparing a phase permeability regulating and water-controlling agent for heavy oil reservoirs, characterized in that, Includes the following steps: (1) Weigh out 50-70 parts of D80 solvent oil, 8-20 parts of alkyl acrylate or its derivatives, 5-15 parts of divinylbenzene, 5-20 parts of vinyl acetate, and 0.1-0.2 parts of azobisisobutyronitrile by weight. Alkyl acrylate or its derivatives, divinylbenzene, and vinyl acetate were added sequentially to D80 solvent oil. The mixture was heated to 50°C–80°C and stirred until completely dissolved. Azobisisobutyronitrile (AIBN) was then added under an inert gas atmosphere, and the reaction was carried out for 4–10 hours. After separation and purification, the polymer shown in Formula I was obtained. Wherein, R1 is an alkyl group with 10-18 carbon atoms, R2 is a methyl group or H, and a, b, c are the degree of polymerization; (2) Weigh 30-60 parts of the polymer shown in Formula I, 30-60 parts of the organic solvent, and 3-15 parts of the nanomaterials by weight. Add an organic solvent to the reactor, heat to 50℃~80℃, start stirring, control the speed to 500r~2000r / min, add the polymer shown in Formula I, stir until the polymer is completely dissolved, add nanomaterials, and continue stirring for 1~3h to obtain the product.

10. The preparation method according to claim 9, characterized in that, The organic solvent is one or more of 200# solvent oil, C9 aromatic hydrocarbons, D80 solvent oil, and D100 solvent oil; Preferably, the nanomaterial is one or more of nano-silica, nano-titanium dioxide, nano-molybdenum disulfide, and nano-zinc sulfide.

11. The relative permeability regulating and water-controlling production enhancer for heavy oil reservoirs according to any one of claims 1-8, and the application of the relative permeability regulating and water-controlling production enhancer prepared by the method of claim 9 or 10 in increasing production in heavy oil reservoirs.

12. The application according to claim 11, characterized in that, The heavy oil reservoir water control and production enhancement agent and nitrogen are simultaneously applied to the displacement of the heavy oil reservoir.

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