Shale oil reservoir integrated blocking remover and blocking removal method

Abstract

The invention discloses a shale oil reservoir integrated blocking remover and a blocking removal method, and relates to the technical field of oil exploitation. The blocking remover is prepared from the following components in parts by weight: 30-50 parts of inorganic blocking removal liquid, 10-30 parts of organic blocking removal liquid, 10-30 parts of degradable suspended gel balls and 3-10 parts of an oil-water dispersing agent. The blocking removal method comprises the steps that the inorganic blocking removal liquid serves as an agent A, the oil-water dispersing agent and the organic blocking removal liquid are evenly stirred to serve as an agent B, the degradable suspended gel balls serve as an agent C, and the agent A, the agent B and the agent C are mixed, evenly stirred and then injected into the stratum. The device has the characteristic of integrating temporary plugging, inorganic plugging removal and organic plugging removal, has the effect of plugging a crack opening during operation, does not need to consider the influence of fracturing heterogeneity of a long well section, and can also avoid the waste of plugging removal liquid of the long well section, so that the plugging removal procedure can be effectively simplified, the plugging removal efficiency can be effectively improved, and the cost is reduced. The technical problem that an existing acidification blockage removal measure is not suitable for shale oil reservoir blockage removal is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil exploitation, in particular to a shale oil reservoir integrated plugging removal agent and a plugging removal method. BACKGROUND

[0002] With the world energy supply becoming increasingly tight, oil exploration and development is facing the challenges of difficulty in discovering high-quality oil reserves and difficulty in stabilizing the production of developed major oilfields. Developing new oilfields and improving the oil recovery of existing reservoirs has always been the technical focus of oil development. Under such a background, domestic and foreign oilfields are constantly exploring and developing unconventional reservoirs, such as deep, low-permeability, ultra-low-permeability, shale, heavy oil, and natural gas hydrate.

[0003] China has rich shale oil resources, but due to the characteristics of shale oil, such as complex structural conditions, severe multi-stage structural damage, high content of reservoir clay minerals, low formation pressure coefficient, high fluid viscosity, and low gas-oil ratio, it is not easy to exploit shale oil, especially as production proceeds, the production of shale oil wells will rapidly decrease due to insufficient formation energy and plugging damage to the near wellbore and wellbore caused by production. Therefore, how to effectively remove the plug has become the simplest and low-cost measure to improve, maintain the production and prolong the life cycle of shale wells.

[0004] At present, acidizing plugging removal is the most common and low-cost effective measure for conventional wells, but this conventional acidizing plugging removal measure is not suitable for plugging removal in shale oil reservoirs, because: (1) Shale wells are all exploited by horizontal wells, so the well section is long; (2) Shale wells have adopted large-scale staged fracturing measures, so there is a serious heterogeneity in the well section, such as some well sections being fractured and some well sections not being fractured, and it is not known in actual production which well sections in the formation are fractured and which well sections are not fractured; (3) Shale layers have high shale content and low permeability.

[0005] Based on the above reasons, the plugging removal of shale oil reservoirs is difficult in the following aspects: the long well section requires a large amount of acid, and a large amount of acid is wasted in the fractured cracks; the position of the fractured well section is uncertain, so it is not possible to inject acid at a specific point; the poor physical properties of shale reservoirs cause serious damage and plugging, especially the organic and inorganic mixed plugging formed in oil wells. Therefore, if the conventional acidizing plugging removal measure is used to remove the plugging of shale oil reservoirs, there will be technical problems such as multiple rounds of plugging removal being cumbersome, the plugging removal position being unclear, a large amount of plugging removal fluid being wasted, and mixed plugging causing serious damage.

[0006] Therefore, in view of the characteristics of shale oil reservoirs, it is necessary to propose a new plugging removal technology to solve the above technical problems. SUMMARY

[0007] The shale oil reservoir integrated plugging agent and the plugging removal method have the characteristics that temporary plugging, inorganic plugging removal and organic plugging removal are integrated, the shale oil reservoir integrated plugging agent has the effect of plugging the crack opening during operation, the influence of long well section fracturing heterogeneity does not need to be considered, and the waste of the long well section plugging removal liquid can be avoided, so that the plugging removal procedure can be effectively simplified and the plugging removal efficiency can be improved, and the technical problem that the existing acidification plugging removal measure is not suitable for the plugging removal of the shale oil reservoir is solved.

[0008] To achieve the above object, the technical scheme adopted by the present application is as follows: A shale oil reservoir integrated plugging agent, by weight, consists of the following components: 30-50 parts of inorganic plugging removal liquid, 10-30 parts of organic plugging removal liquid, 10-30 parts of degradable suspended gel ball, 3-10 parts of oil-water dispersing agent.

[0009] The total amount of the inorganic plugging removal liquid is 100 parts, and specifically consists of the following components by weight: 5-20 parts of acid, 1-5 parts of fluorine-containing acid / salt, 3-5 parts of chelating agent, 1-5 parts of corrosion inhibitor, 1-5 parts of clay stabilizer, and the rest is water.

[0010] The acid is one or several kinds of hydrochloric acid, formic acid, acetic acid and aminosulfonic acid mixed in any proportion.

[0011] The fluorine-containing acid / salt is one or several kinds of hydrofluoric acid, fluoroboric acid and ammonium fluoride mixed in any proportion.

[0012] The chelating agent is one or several kinds of EDTA, EDTA.2Na, EDTA.4Na, DTPA, HEDTA, NTA, EGTA, ATMP, HEDP, EDTMP, DTPMP, ATP and HPMA mixed in any proportion.

[0013] The corrosion inhibitor is one or several kinds of mercaptan, polyethylene glycol ether, sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate, diethylene triamine, hexamethylene tetramine, butynyl alcohol, butynediol, imidazoline oleic acid, 4-methyl pyridine and 4-vinyl pyridine mixed in any proportion.

[0014] The clay stabilizer is one or several kinds of 2,3 epoxy propyl trimethyl ammonium chloride, gamma-aminopropyl triethoxysilane, polydimethyl diallyl ammonium chloride, hexadecyl trimethyl ammonium chloride and hexadecyl benzyl dimethyl ammonium chloride mixed in any proportion.

[0015] The organic plugging removal liquid is a mixture of petroleum products and biological oil, the total amount of the organic plugging removal liquid is 100 parts, the weight of the biological oil is 30-70 parts, and the rest is petroleum products.

[0016] The petroleum product is one of diesel, kerosene, gasoline, and petroleum ether, or a mixture of several in any proportion.

[0017] The bio-oil is one of coconut oil, palm oil, and isopropyl myristate, or a mixture of several in any proportion.

[0018] The biodegradable suspension gel spheres are composed of the following components in parts by weight: 50-90 parts water, 2-10 parts biodegradable material, 0-1 part toughening material, 5-20 parts bio-oil, 1-3 parts oil-water dispersant, 0.1-1 part inorganic salt, 0-2 parts acid regulator.

[0019] The method for preparing the biodegradable suspension gel spheres is as follows: S1: Add inorganic salt to water and stir evenly, then add bio-oil and 70-80% oil-water dispersant and stir evenly, then add toughening material and dissolve completely and stir evenly, then add biodegradable material and stir evenly, and finally add acid regulator and stir evenly to obtain the prepared adhesive solution. S2: The adhesive liquid is poured into the molding liquid through a ball-dropping machine to form the gel balls, and then the molding liquid is filtered to separate the gel balls. S3: Add 20-30% oil-water dispersant to the gel balls and stir evenly. Then place them in a curing tank and cure at 50-70℃ for 3-10 minutes to obtain biodegradable suspension gel balls with a particle size of 1-2cm.

[0020] The biodegradable material is one of agar, sodium alginate, pectin, and propylene glycol alginate, or a mixture of several in any proportion.

[0021] The toughening material is one of xanthan gum, guar gum, gum arabic, polyacrylamide, and polyethylene glycol, or a mixture of several in any proportion.

[0022] The bio-oil is the same as the bio-oil in the organic unblocking solution.

[0023] The inorganic salt is one of calcium carbonate, calcium lactate, ferrous chloride, ferrous oxide, dolomite, and limestone, or several mixed in any proportion.

[0024] The acid regulator is one of citric acid, sodium citrate, gluconolactone, ammonium chloride, acetic acid, and sodium acetate, or a mixture of several in any proportion.

[0025] The preparation method of the oil-water dispersant: M1: At room temperature, add acid anhydride, bio-oil, mutual solvent and polyol to the reaction vessel, stir under nitrogen gas, heat to 200-230℃ and react for 2-6 hours to obtain intermediate product; M2: Add the intermediate product to the polyether polyol, then add the alkaline regulator, stir under nitrogen for 30 minutes, then add the catalyst under nitrogen protection and stir evenly, and heat to 150-180℃ to react for 3-5 hours to obtain the oil-water dispersant.

[0026] The acid anhydride is one of succinic anhydride, maleic anhydride, and fumaric anhydride.

[0027] The polyol is one of ethylene glycol, glycerol, pentaerythritol, polytetrahydrofuran glycol, polyoxytetramethylene glycol, or a mixture of several in any proportion.

[0028] The selected bio-oil must be the same as the bio-oil used to prepare the organic unblocking solution and water dispersant.

[0029] The mutual solvent is ethylene glycol butyl ether.

[0030] The selected polyether polyol is a conventional commercially available polyether polyol.

[0031] The catalyst is one of dibutyltin dilaurate and stannous octoate.

[0032] The alkalinity regulator is one of sodium bicarbonate, sodium hydroxide, or ammonia.

[0033] An integrated unblocking method for shale oil reservoirs, the unblocking process of which is as follows: Inorganic unblocking fluid is used as agent A, oil-water dispersant and organic unblocking fluid are mixed evenly and used as agent B, and biodegradable suspended gel balls are used as agent C. Agent A, agent B and agent C are mixed and stirred evenly and then injected into the formation.

[0034] The advantages of using this invention are: 1. This invention mainly consists of 30-50 parts of inorganic unblocking fluid, 10-30 parts of organic unblocking fluid, 10-30 parts of biodegradable suspension gel balls, and 3-10 parts of oil-water dispersant. Through the combination of these components in this specific ratio, organic unblocking, inorganic unblocking, and temporary blockage reversal can be efficiently and organically synergistically achieved, thereby realizing efficient, low-cost, and convenient integrated unblocking.

[0035] Specifically, the organic unblocking fluid is composed of at least one petroleum product and at least one bio-oil. Their synergistic effect effectively cleans organic damage and disperses the entire system. Furthermore, the similar structures of the organic unblocking fluid and the oil-water dispersant prepared from bio-oil not only ensure good miscibility but also allow for effective combination of the organic unblocking fluid and the oil-water dispersant, providing a foundation for efficient dispersion. The biodegradable suspended gel balls used for temporary plugging are aqueous materials. Introducing the same bio-oil as in the organic unblocking fluid gives the temporarily plugged biodegradable suspended gel balls amphiphilic characteristics, resulting in better uniform dispersion in both organic and inorganic unblocking systems. In addition, the biodegradable suspended gel balls are prepared using polysaccharides containing ester structures and high-toughness polymers. The polysaccharides containing ester structures are unstable under acidic conditions, allowing the biodegradable suspended gel balls to possess high strength while gradually transforming into gel degradation in acidic environments, achieving self-cleaning functionality.

[0036] Furthermore, inorganic unblocking fluids are mainly used to dissolve inorganic scale, corrosion products, and transported mineral particles in the formation. Due to heterogeneity, these fluids struggle to penetrate low-permeability areas, and organic damaging films hinder their effective removal of these inorganic pollutants. Biodegradable suspended gel balls can effectively temporarily plug high-permeability areas and perforation pores, while promoting the effective dissolution of severely damaged areas by the inorganic unblocking fluid. Organic unblocking fluids effectively clean organic pollutants, thus promoting the effective removal of inorganic pollutants by the inorganic unblocking fluid. Oil-water dispersants ensure a uniformly mixed and dispersed state throughout the system, enabling different unblocking materials to perform their respective unblocking functions.

[0037] Furthermore, the weight percentages of each component in this invention must not be less than a predetermined range; otherwise, their synergistic unblocking effect will be affected. For example, if the inorganic unblocking fluid is too low, it cannot effectively dissolve inorganic harmful substances; if the organic unblocking fluid is too low, it cannot assist the inorganic unblocking fluid in contacting and dissolving inorganic harmful substances; if the biodegradable suspended gel spheres are too low, the unblocking fluid will enter the hyperpermeable area, resulting in ineffective unblocking; and if the oil-water dispersant is too low, it will be difficult to uniformly disperse the unblocking system for synergistic unblocking.

[0038] In summary, the system of this invention, through the synergistic effect of its components, achieves integrated functions of organic deblocking, inorganic deblocking, and temporary deblocking reversal, greatly simplifying the operation process. Simultaneously, the various components of the system are prepared and modified from raw materials through a similar compatibility mechanism, resulting in excellent dispersion and miscibility, thus establishing the foundation for integrated operations.

[0039] 2. Existing unblocking operations typically involve injecting chemical materials with different effects in stages, especially during segmented operations in long well sections. This requires multiple injections of plugging and unblocking agents. If the unblocking agent is further divided into organic and inorganic unblocking agents, the procedure becomes injection of temporary plugging agent, organic unblocking agent, and inorganic unblocking agent. Furthermore, the temporary plugging agent requires a separate carrier fluid to be introduced into the formation, making the entire process cumbersome, involving multiple repetitive container transfers, and difficult to implement. In contrast, this invention only requires mixing and stirring all components thoroughly before directly injecting them into the formation, achieving an integrated unblocking operation and greatly simplifying the construction procedure.

[0040] 3. In existing technologies, the locations of fractures and unblocking in the well section are unclear. Therefore, during long well operations, a large amount of unblocking fluid is injected into the fracture location, resulting in ineffective unblocking. This invention, however, can unblock horizontal wells that have undergone fracturing in a single operation, effectively reducing the waste of unblocking fluid, saving costs, and improving unblocking efficiency.

[0041] 4. Compared with the prior art, the present invention greatly simplifies the operation procedure and improves the efficiency of operation, thus having good application prospects. Detailed Implementation

[0042] In a first aspect, the present invention provides an integrated unblocking agent for shale oil reservoirs, which, by weight, comprises the following components: 30-50 parts inorganic unblocking solution, 10-30 parts organic unblocking solution, 10-30 parts biodegradable suspension gel balls, and 3-10 parts oil-water dispersant.

[0043] The total amount of the inorganic unblocking solution is 100 parts, specifically composed of the following components by weight: 5-20 parts acid, 1-5 parts hydrofluoric acid / salt, 3-5 parts chelating agent, 1-5 parts corrosion inhibitor, 1-5 parts clay stabilizer, and the remainder is water. The acid is one of hydrochloric acid, formic acid, acetic acid, and aminosulfonic acid, or a mixture of several in any proportion.

[0044] The fluorinated acid / salt is one of hydrofluoric acid, fluoroboric acid, and ammonium fluoride, or a mixture of several in any proportion.

[0045] The chelating agent is one or a mixture of several of the following in any proportion: EDTA, EDTA.2Na, EDTA.4Na, DTPA, HEDTA, NTA, EGTA, ATMP, HEDP, EDTMP, DTPMP, ATP, and HPMA.

[0046] The corrosion inhibitor is one or a mixture of several of the following: thiol, polyethylene glycol ether, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, diethylenetriamine, hexamethylenetetramine, butynediol, butynediol, imidazoline oleate, 4-methylpyridine, and 4-vinylpyridine.

[0047] The clay stabilizer is one or a mixture of several of the following: 2,3-epoxypropyltrimethylammonium chloride, γ-aminopropyltriethoxysilane, polydimethyldiallylammonium chloride, hexadecyltrimethylammonium chloride, and hexadecylbenzyldimethylammonium chloride in any proportion.

[0048] The organic unblocking fluid is a mixture of petroleum products and bio-oils, with a total organic unblocking fluid volume of 100 parts, bio-oils comprising 30-70 parts by weight, and the remainder being petroleum products. The petroleum products are one of diesel, kerosene, gasoline, and petroleum ether, or a mixture of several in any proportion.

[0049] The bio-oil is one of coconut oil, palm oil, and isopropyl myristate, or a mixture of several in any proportion.

[0050] The biodegradable suspension gel spheres are composed of the following components in parts by weight: wherein, 50-90 parts water, 2-10 parts biodegradable material, 0-1 part toughening material, 5-20 parts bio-oil, 1-3 parts oil-water dispersant, 0.1-1 part inorganic salt, 0-2 parts acid regulator.

[0051] The method for preparing the biodegradable suspension gel spheres is as follows: S1: First, add inorganic salt to water and stir evenly. Then, add bio-oil and 70-80% oil-water dispersant and stir evenly. Next, add toughening material, dissolve completely and stir evenly. Then, add biodegradable material and stir evenly. Finally, add acid regulator and stir evenly to obtain the prepared adhesive solution.

[0052] S2: The adhesive liquid is poured into the molding liquid through a ball-dropping machine to form the gel balls, and then the molding liquid is filtered to separate the gel balls.

[0053] S3: Add 20-30% oil-water dispersant to the gel balls and stir evenly. Then place them in a curing tank and cure at 50-70℃ for 3-10 minutes. After curing, biodegradable suspension gel balls with a particle size of 1-2cm are obtained.

[0054] The biodegradable material is one of agar, sodium alginate, pectin, and propylene glycol alginate, or a mixture of several in any proportion.

[0055] The toughening material is one of xanthan gum, guar gum, gum arabic, polyacrylamide, and polyethylene glycol, or a mixture of several in any proportion.

[0056] The bio-oil is the same as the bio-oil in the organic unblocking solution.

[0057] The inorganic salt is one of calcium carbonate, calcium lactate, ferrous chloride, ferrous oxide, dolomite, and limestone, or several mixed in any proportion.

[0058] The acid regulator is one of citric acid, sodium citrate, gluconolactone, ammonium chloride, acetic acid, and sodium acetate, or a mixture of several in any proportion.

[0059] The preparation method of the oil-water dispersant: M1: At room temperature, add acid anhydride, bio-oil, mutual solvent and polyol to the reaction vessel, stir under nitrogen gas, heat to 200-230℃ and react for 2-6 hours to obtain intermediate product.

[0060] M2: Add the intermediate product to the polyether polyol, then add the alkaline regulator, stir under nitrogen for 30 minutes, then add the catalyst under nitrogen protection and stir evenly, and heat to 150-180℃ to react for 3-5 hours to obtain the oil-water dispersant.

[0061] The mass of the acid anhydride is 0.5-1.5 times that of the biological oil. The miscible solvent is 3-10% of the combined mass of the acid anhydride and the biological oil. The polyol is 30-50% of the combined mass of the acid anhydride and the biological oil. The polyether polyol has the same mass as the polyanhydride and the biological oil. When an alkaline regulator is added, the pH of the system is adjusted to 8-10.

[0062] The acid anhydride is one of succinic anhydride, maleic anhydride, and fumaric anhydride.

[0063] The polyol is one of ethylene glycol, glycerol, pentaerythritol, polytetrahydrofuran glycol, polyoxytetramethylene glycol, or a mixture of several in any proportion.

[0064] The selected bio-oil must be the same as the bio-oil used to prepare the organic unblocking solution and water dispersant.

[0065] The mutual solvent is ethylene glycol butyl ether.

[0066] The selected polyether polyol is a conventional commercially available polyether polyol.

[0067] The catalyst is one of dibutyltin dilaurate and stannous octoate.

[0068] The alkalinity regulator is one of sodium bicarbonate, sodium hydroxide, or ammonia.

[0069] Secondly, this embodiment also provides an integrated unblocking method for shale oil reservoirs, the unblocking process of which is as follows: The unblocking agent is divided into three systems: inorganic unblocking fluid as agent A, oil-water dispersant and organic unblocking fluid mixed evenly as agent B, and biodegradable suspended gel balls as agent C. Agents A, B and C can be mixed in advance or on-site. During operation, agents A, B and C are mixed and stirred evenly before being injected into the formation.

[0070] The present invention will be further described in detail below with reference to specific embodiments.

[0071] Example 1 This embodiment simulates the conversion of temporary plugging agents to acidizing in a laboratory setting using core displacement tests, and utilizes an integrated unblocking agent for shale oil reservoir modification. Before the experiment, the required working fluids are prepared: inorganic unblocking agent A1, agent B1 (a mixture of oil-water dispersant and organic unblocking agent), and biodegradable suspension gel ball agent C1. During the construction phase, agents A1, B1, and C1 are mixed and stirred evenly before being injected into the formation.

[0072] Step 1: Preparation of Agent A1: 5 parts hydrochloric acid + 4 parts hydrofluoric acid + 3 parts EDTA·2Na + 1 part thiol + 1 part 2,3-epoxypropyltrimethylammonium chloride, with the remainder being water. Measure 10 ml of hydrochloric acid, 3 ml of hydrofluoric acid, 2 ml of thiol, and 2 ml of 2,3-epoxypropyltrimethylammonium chloride using a graduated cylinder. Weigh 3 g of EDTA·2Na using an analytical balance. Dissolve all of these in a beaker of deionized water and stir with a magnetic stirrer for 1 hour until fully dissolved to obtain inorganic unblocking agent A1.

[0073] Step 2: Preparation of intermediate oil-water dispersant: 5 parts succinic anhydride + 10 parts coconut oil + 0.45 parts ethylene glycol butyl ether + 4.5 parts ethylene glycol + 15 parts polyether polyol + 0.5 parts alkalinity regulator + 0.2 parts dibutyltin dilaurate. At room temperature, add 5 ml succinic anhydride, 10 ml coconut oil, 0.45 ml ethylene glycol butyl ether, and 4.5 ml ethylene glycol to a reaction vessel. Stir under nitrogen purging and heat to 200℃ for 2 hours to obtain product R1. Mix product R1 with 15 ml polyether polyol until homogeneous, then add 0.5 g sodium bicarbonate and stir under nitrogen purging for 30 minutes. Then, under nitrogen protection, add the catalyst dibutyltin dilaurate and stir until homogeneous. Heat to 150℃ and react for 3 hours to obtain the oil-water dispersant.

[0074] Step 3: Preparation of Agent B1: Step 3.1: 30 parts coconut oil + 70 parts kerosene. Measure 70ml of kerosene and 30ml of coconut oil using a measuring cylinder, mix them evenly, and you will get the organic unblocking solution.

[0075] Step 3.2: Add the organic unblocking solution prepared in step 3.1 and the 3 ml oil-water dispersant prepared in step 2 into a beaker of deionized water, and then stir with a magnetic stirrer for 1 hour to mix them thoroughly to obtain agent B1.

[0076] Step 4: Preparation of Agent C1: 50 parts water + 10 parts bio-oil + 6 parts biodegradable material + 2 parts oil-water dispersant + 0.5 parts toughening material + 0.1 parts inorganic salt + 0.5 parts acid regulator. Measure 50 ml of water and 10 ml of coconut oil using a graduated cylinder. Weigh 6 g of agar, 0.5 g of xanthan gum, 0.1 g of calcium carbonate, and 0.5 g of citric acid using an analytical balance. In the second step, first add the inorganic salt to the water and stir until homogeneous. Then add 80% oil-water dispersant and coconut oil and stir until homogeneous. Next, add xanthan gum and dissolve completely, stirring until homogeneous. Then add agar and stir until homogeneous. Finally, add calcium carbonate and stir until homogeneous to prepare the gel solution. In the third step, pour the gel solution into the molding liquid using a dropper to form gel balls, then filter the molding liquid to separate the gel balls. In the fourth step, add 20% oil-water dispersant to the gel balls and stir until homogeneous. Then place them in a curing tank and cure at 50°C for 3 minutes. This yields biodegradable suspension gel balls.

[0077] Step 5: Mix 45 parts of Agent A1, 25 parts of Agent B1 (Agent B1 includes 20 parts of organic unblocking fluid and 5 parts of oil-water dispersant), and 30 parts of Agent C1 evenly to obtain an integrated unblocking agent for shale oil reservoirs.

[0078] This embodiment uses core displacement tests to simulate temporary plugging agent redirection and acidizing in the laboratory. The experiment uses core 1 and core 2 from the real reservoir (the cores are from the shale cores of the CQ oilfield reservoir, with a 0.5 mm wide and 50 mm long fracture in the middle of the core).

[0079] For core 1, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and the initial permeability of core 1 was measured to be 1.21 mD. Conventional temporary plugging agent was first injected into core 1 at a flow rate of 2 mL / min. When the injection pressure increased to 3 MPa, the injection of interpenetrating network gel temporary plugging agent was stopped. After waiting for 1 hour for the temporary plugging agent to completely gel, 50 mL of 20% hydrochloric acid was injected at a flow rate of 2 mL / min, followed by a 3% NH4Cl solution at a flow rate of 2 mL / min. The permeability was measured to be 4.36 mD, and the modification efficiency was 360.33%.

[0080] For core 2, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and the initial permeability of core 2 was measured to be 1.59 mD. After mixing and stirring agents A, B, and C evenly in the storage tank, the storage tank valve was opened, and an integrated shale oil reservoir unblocking agent was injected into core 2 at a flow rate of 2 mL / min. Then, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and its permeability was measured to be 12.33 mD, with a stimulation efficiency of 775.47%.

[0081] The comparison shows that the difference between the indoor simulations of core 1 and core 2 lies in whether or not the integrated shale oil reservoir unblocking agent of the present invention was used. The stimulation efficiency of core 2, which used the integrated shale oil reservoir unblocking agent of the present invention, was 2.53 times that of core 1, indicating that the technical effect achieved by the present invention is better.

[0082] Example 2 This embodiment simulates the shift of temporary plugging agents to acidizing in a laboratory setting using core displacement tests, and utilizes an integrated unblocking agent for shale oil reservoir modification. Before the experiment, the necessary working fluids are prepared: inorganic unblocking agent A2, agent B2 (a mixture of oil-water dispersant and organic unblocking agent), and biodegradable suspended gel balls C2. During the application process, agents A2, B2, and C2 are mixed thoroughly and injected into the formation.

[0083] Step 1: Preparation of Agent A2: 10 parts acetic acid + 3 parts fluoroboric acid + 5 parts EGTA + 3 parts sodium dodecyl sulfonate + 3 parts γ-aminopropyltriethoxysilane, with the remainder being water. Measure 10 ml of acetic acid, 3 ml of fluoroboric acid, 1 ml of sodium dodecyl sulfonate, and 1 ml of γ-aminopropyltriethoxysilane using a graduated cylinder. Weigh 5 g of HEDTA using an analytical balance. Dissolve all of these in a beaker of deionized water and stir with a magnetic stirrer for 1 hour until fully dissolved to obtain the inorganic unblocking solution.

[0084] Step 2: Preparation of intermediate oil-water dispersant: 10 parts maleic anhydride + 10 parts palm oil + 1.5 parts ethylene glycol butyl ether + 8 parts glycerol + 20 parts polyether polyol + 0.5 parts alkalinity regulator + 0.2 parts stannous octoate. At room temperature, add 10 ml maleic anhydride, 10 ml palm oil, 1.5 ml ethylene glycol butyl ether, and 8 ml glycerol to a reaction vessel. Stir under nitrogen purging and heat to 210℃ for 4 hours to obtain product R2. Add 0.5 g sodium hydroxide to product R2 and 20 ml polyether polyol, stir under nitrogen purging for 30 minutes, then stir until homogeneous with the catalyst stannous octoate under nitrogen purging. Heat to 165℃ and react for 4 hours to obtain the oil-water dispersant.

[0085] Step 3: Preparation of Agent B2: Step 3.1: 40 parts palm oil + 60 parts gasoline. Measure 60ml of gasoline and 40ml of palm oil using a measuring cylinder, mix them evenly, and you will get the organic unblocking solution.

[0086] Step 3.2: Add the organic unblocking solution obtained in step 3.1 and 1 ml of oil-water dispersant obtained in step 2 into a beaker of deionized water, and then stir with a magnetic stirrer for 1 hour to mix them thoroughly to obtain agent B2.

[0087] Step 4: Preparation of C2 agent: 70 parts water + 20 parts bio-oil + 1 part oil-water dispersant + 5 parts biodegradable material + 1 part toughening material + 0.5 parts inorganic salt + 2g acid regulator. Measure 70ml water and 20ml palm oil using a graduated cylinder. Weigh 5g sodium alginate, 1g guar gum, 0.5g calcium carbonate, and 2g sodium citrate using an analytical balance. In the second step, first add the inorganic salt to the water and stir until homogeneous. Then add 70% oil-water dispersant and palm oil and stir until homogeneous. Next, add guar gum and dissolve completely, stirring until homogeneous. Then add sodium alginate and stir until homogeneous. Finally, add calcium carbonate and stir until homogeneous to prepare the gel solution. In the second step, pour the gel solution into the molding liquid using a dropper to form gel balls, then filter the molding liquid to separate the gel balls. In the third step, add 30% oil-water dispersant to the gel balls and stir until homogeneous. Then place them in a curing tank and cure at 70℃ for 10 minutes. This yields biodegradable suspension gel balls.

[0088] Step 5: Mix 30 parts of Agent A2, 30 parts of Agent B2 (Agent B2 includes 20 parts of organic unblocking fluid and 10 parts of oil-water dispersant), and 25 parts of Agent C2 evenly to obtain an integrated unblocking agent for shale oil reservoirs.

[0089] In this embodiment, a core displacement test was used to simulate the temporary plugging agent shifting to acidizing in the laboratory. The experiment used real reservoir cores, core 1 and core 2 (the cores came from the shale cores of the CQ oilfield reservoir, with a split in the middle of the core, the width of which was 0.5 mm and the length of which was 50 mm).

[0090] For core 1, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and the initial permeability of core 1 was measured to be 1.54 mD. Conventional temporary plugging agent was first injected into core 1 at a flow rate of 2 mL / min. When the injection pressure increased to 3 MPa, the injection of the temporary plugging agent was stopped, and after waiting for 1 hour for the temporary plugging agent to completely gel, 50 mL of 20% hydrochloric acid was injected at a flow rate of 2 mL / min, followed by a 3% NH4Cl solution at a flow rate of 2 mL / min. The permeability was measured to be 4.61 mD, and the modification efficiency was 299.33%.

[0091] For core 2, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and the initial permeability of core 2 was measured to be 1.73 mD. After mixing and stirring agents A2, B2, and C2 evenly in the storage tank, the storage tank valve was opened, and an integrated shale oil reservoir unblocking agent was injected into core 2 at a flow rate of 2 mL / min. Then, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and its permeability was measured to be 16.22 mD, with a stimulation efficiency of 937.57%.

[0092] The comparison shows that the difference between the indoor simulations of core 1 and core 2 lies in whether or not the integrated shale oil reservoir unblocking agent of the present invention is used. The stimulation efficiency of core 2, which uses the integrated shale oil reservoir unblocking agent of the present invention, is 3.13 times that of core 1, indicating that the technical effect achieved by the present invention is better.

[0093] Example 3 This embodiment simulates the temporary plugging agent redirection to acidizing in a laboratory setting using a core displacement test, and utilizes an integrated unblocking agent for shale oil reservoir modification. Before the experiment, the necessary working fluids are prepared: inorganic unblocking agent A3, agent B3 (a mixture of oil-water dispersant and organic unblocking agent), and biodegradable suspended gel ball agent C3. During the application process, agents A3, B3, and C3 are mixed thoroughly and injected into the formation.

[0094] Step 1: Preparation of Agent A3: 15 parts sulfamic acid + 5 parts ammonium fluoride + 4 parts HEDP + 5 parts imidazoline oleate + 5 parts hexadecyltrimethylammonium chloride, with the remainder being water. Measure 15g of sulfamic acid, 2g of ammonium fluoride, 1ml of imidazoline oleate, and 1ml of hexadecyltrimethylammonium chloride using a graduated cylinder. Weigh 3g of HEDP using an analytical balance. Dissolve all of these ingredients in a beaker of deionized water and stir with a magnetic stirrer for 1 hour until fully dissolved to obtain the inorganic unblocking solution.

[0095] Step 2: Preparation of intermediate oil-water dispersant: 15 parts fumaric anhydride + 10 parts isopropyl myristate + 2.5 parts ethylene glycol butyl ether + 12.5 parts pentaerythritol + 25 parts polyether polyol + 0.5 parts alkalinity regulator + 0.2 parts dibutyltin dilaurate. At room temperature, add 15 ml fumaric anhydride, 10 ml isopropyl myristate, 2.5 ml ethylene glycol butyl ether, and 12.5 ml pentaerythritol to a reaction vessel. Stir under nitrogen purging and heat to 230℃ for 6 hours to obtain product R3. Add 0.5 ml ammonia to product R3 and 25 ml polyether polyol, stir under nitrogen purging for 30 minutes, then stir the catalyst dibutyltin dilaurate evenly under nitrogen purging and heat to 180℃ for 5 hours to obtain the oil-water dispersant.

[0096] Step 3: Preparation of Agent B3: Step 3.1: 50 parts petroleum ether + 50 parts gasoline. Measure 50 ml of isopropyl myristate and 50 ml of petroleum ether using a graduated cylinder, mix them evenly, and you will get the organic unblocking solution.

[0097] Step 3.2: Add the organic unblocking solution obtained in step 3.1 and 1 ml of oil-water dispersant obtained in step 2 into a beaker of deionized water, and then stir with a magnetic stirrer for 1 hour to mix them thoroughly to obtain agent B3.

[0098] Step 4: Preparation of C3 agent: 90 parts water + 15 parts bio-oil + 3 parts oil-water dispersant + 10 parts biodegradable material + 1 part inorganic salt. Measure 90 ml of water and 15 ml of isopropyl myristate using a graduated cylinder, and weigh 5 g of pectin and 1 g of calcium lactate using an analytical balance. First, add the inorganic salt to the water and stir until homogeneous. Then add 70% oil-water dispersant and isopropyl myristate and stir until homogeneous. Next, add polyacrylamide and dissolve completely, stirring until homogeneous. Then add pectin and stir until homogeneous. Finally, add calcium carbonate and stir until homogeneous to prepare the gel solution. Second, pour the gel solution into a molding liquid using a dropper to form gel balls, then filter the molding liquid to separate the gel balls. Third, add 25% oil-water dispersant to the gel balls and stir until homogeneous. Then place the gel balls in a curing tank and cure at 60°C for 8 minutes. This yields biodegradable suspension gel balls.

[0099] Step 5: Mix 50 parts of A3 agent, 13 parts of B3 agent (B3 agent includes 10 parts of organic unblocking fluid and 3 parts of oil-water dispersant), and 10 parts of C3 agent evenly to obtain an integrated unblocking agent for shale oil reservoirs.

[0100] In this embodiment, a core displacement test was used to simulate the temporary plugging agent shifting to acidizing in the laboratory. The experiment used real reservoir cores, core 1 and core 2 (the cores came from the shale cores of the CQ oilfield reservoir, with a split in the middle of the core, the width of which was 0.5 mm and the length of which was 50 mm).

[0101] For core 1, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and the initial permeability of core 1 was measured to be 1.29 mD. A conventional temporary plugging agent was first injected into core 1 at a flow rate of 2 mL / min. When the injection pressure increased to 3 MPa, the injection of the temporary plugging agent was stopped, and the injection was allowed to wait for 1 hour for the temporary plugging agent to completely gel. Then, 50 mL of 20% hydrochloric acid was injected at a flow rate of 2 mL / min, followed by a 3% NH4Cl solution at a flow rate of 2 mL / min. The permeability was measured to be 4.12 mD, and the modification efficiency was 319.38%.

[0102] For core 2, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and the initial permeability of core 2 was measured to be 1.36 mD. After mixing and stirring agents A3, B3, and C3 evenly in the storage tank, the storage tank valve was opened, and an integrated shale oil reservoir unblocking agent was injected into core 2 at a flow rate of 2 mL / min. Then, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and its permeability was measured to be 13.26 mD, with a stimulation efficiency of 975%.

[0103] The comparison shows that the difference between the indoor simulations of core 1 and core 2 lies in whether or not the integrated shale oil reservoir unblocking agent of the present invention is used. The stimulation efficiency of core 2, which uses the integrated shale oil reservoir unblocking agent of the present invention, is 3.05 times that of core 1, indicating that the technical effect achieved by the present invention is better.

[0104] Example 4 This embodiment simulates the temporary plugging agent shifting to acidizing in a laboratory setting using a core displacement test, and utilizes an integrated unblocking agent for shale oil reservoir modification. Before the experiment, the necessary working fluids are prepared: inorganic unblocking agent A4, agent B4 (a mixture of oil-water dispersant and organic unblocking agent), and biodegradable suspension gel ball agent C4. During the application process, agents A4, B4, and C4 are mixed thoroughly and injected into the formation.

[0105] Step 1: Preparation of Agent A4: 20 parts formic acid + 3 parts ammonium fluoride + 3 parts DTPA + 4 parts hexamethylenetetramine + 4 parts polydimethyldiallyl ammonium chloride, with the remainder being water. Measure 12 ml of sulfamic acid, 1 ml of imidazoline oleate, and 1 ml of hexadecyltrimethylammonium chloride using a graduated cylinder. Weigh 3 g of ammonium fluoride, 3 g of DTPA, and 1 g of hexamethylenetetramine using an analytical balance. Dissolve all of these in a beaker of deionized water and stir with a magnetic stirrer for 1 hour until fully dissolved to obtain the inorganic unblocking solution.

[0106] Step 2: Preparation of intermediate oil-water dispersant: 12 parts succinic anhydride + 10 parts isopropyl myristate + 2 parts ethylene glycol butyl ether + 6 parts polyoxytetramethylene glycol + 18 parts polyether polyol + 0.5 parts alkalinity regulator + 0.2 parts stannous octoate. At room temperature, add 12 ml succinic anhydride, 10 ml isopropyl myristate, 2 ml ethylene glycol butyl ether, and 6 ml polyoxytetramethylene glycol to a reaction vessel. Stir under nitrogen purging and heat to 210℃ for 3 hours to obtain product R4. Mix product R4 with 18 ml of polyether polyol until homogeneous, then add 0.5 g sodium bicarbonate and stir under nitrogen purging for 30 minutes. Then, under nitrogen protection, add the catalyst stannous octoate and stir until homogeneous. Heat to 170℃ and react for 4.5 hours to obtain the oil-water dispersant.

[0107] Step 3: Preparation of Agent B4: Step 3.1: 70 parts palm oil + 30 parts diesel oil. Measure 30 ml of diesel oil and 70 ml of palm oil using a measuring cylinder, mix them evenly, and you will get the organic unblocking solution.

[0108] Step 3.2: Add the organic unblocking solution obtained in step 3.1 and 1 ml of oil-water dispersant obtained in step 2 to a beaker of deionized water, and then stir with a magnetic stirrer for 1 hour to mix them thoroughly to obtain agent B4.

[0109] Step 4: Preparation of C4 agent: 60 parts water + 5 parts bio-oil + 1 part oil-water dispersant + 2 parts biodegradable material + 1 part toughening material + 1 part inorganic salt + 2 parts acid regulator. Measure 60 ml of water and 5 ml of isopropyl myristate using a graduated cylinder. Weigh 2 g of propylene glycol alginate, 1 g of gum arabic, 1 g of dolomite, and 2 g of sodium acetate using an analytical balance. First, add the inorganic salt to the water and stir until homogeneous. Then add 75% oil-water dispersant and isopropyl myristate and stir until homogeneous. Next, add gum arabic and dissolve completely, stirring until homogeneous. Then add propylene glycol alginate and stir until homogeneous. Finally, add dolomite and stir until homogeneous to prepare the gel solution. Second, pour the gel solution into the molding liquid using a dropper to form gel balls, then filter the molding liquid to separate the gel balls. Third, add 28% oil-water dispersant to the gel balls and stir until homogeneous. Then place the gel balls in a curing tank and cure at 65°C for 7 minutes. This yields biodegradable suspension gel balls.

[0110] Step 5: Mix 35 parts of A4 agent, 40 parts of B4 agent (B2 agent includes 30 parts of organic unblocking fluid and 10 parts of oil-water dispersant), and 25 parts of C4 agent evenly to obtain an integrated unblocking agent for shale oil reservoirs.

[0111] This embodiment uses core displacement tests to simulate temporary plugging agent redirection and acidizing in the laboratory. The experiment uses core 1 and core 2 from the real reservoir (the cores are from the shale cores of the CQ oilfield reservoir, with a 0.5 mm wide and 50 mm long fracture in the middle of the core).

[0112] For core 1, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and the initial permeability of core 1 was measured to be 1.18 mD. Conventional temporary plugging agent was first injected into core 1 at a flow rate of 2 mL / min. When the injection pressure increased to 3 MPa, the injection of interpenetrating network gel temporary plugging agent was stopped. After waiting for 1 hour for the temporary plugging agent to completely gel, 50 mL of 20% hydrochloric acid was injected at a flow rate of 2 mL / min, followed by a 3% NH4Cl solution at a flow rate of 2 mL / min. The permeability was measured to be 3.2 mD, and the modification efficiency was 271.18%.

[0113] For core 2, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and the initial permeability of core 2 was measured to be 1.24 mD. After mixing and stirring agents A4, B4, and C4 evenly in the storage tank, the storage tank valve was opened, and an integrated shale oil reservoir unblocking agent was injected into core 2 at a flow rate of 2 mL / min. Then, a 3% NH4Cl solution was injected at a flow rate of 2 mL / min, and its permeability was measured to be 8.25 mD, with a stimulation efficiency of 665.32%.

[0114] The comparison shows that the difference between the indoor simulations of core 1 and core 2 lies in whether or not the integrated shale oil reservoir unblocking agent of the present invention was used. The stimulation efficiency of core 2, which used the integrated shale oil reservoir unblocking agent of the present invention, was 2.45 times that of core 1, indicating that the technical effect achieved by the present invention is better.

[0115] It should also be noted that the modification effects of Examples 1, 2, 3, and 4 are different. The difference lies in the fact that the inorganic unblocking fluid in Example 1 uses conventional hydrochloric acid and hydrofluoric acid, which have strong dissolving power and a fast reaction speed, resulting in more severe corrosion at the inlet end. Core 1 uses conventional temporary plugging acidizing modification measures, while core 2 uses the integrated shale oil reservoir unblocking agent of this invention. The modification efficiency of core 2 is 2.53 times that of core 1.

[0116] In Example 2, the inorganic unblocking fluid used slow-reacting acids acetic acid and fluoroboric acid, which have a slow reaction rate, long action distance, and good modification effect. Core 1 used conventional temporary plugging acidizing modification measures, while core 2 used the integrated shale oil reservoir unblocking agent of this invention. The modification efficiency of core 2 was 3.13 times that of core 1.

[0117] In Example 3, the inorganic unblocking fluid uses solid acids aminosulfonic acid and ammonium fluoride. While the reaction rate is slow and the effective range is long, it is convenient to transport, facilitates on-site construction, and yields good modification results. Core 1 used conventional temporary plugging and acidizing modification measures, while core 2 used the integrated shale oil reservoir unblocking agent of this invention. The modification efficiency of core 2 was 3.05 times that of core 1.

[0118] In Example 4, the inorganic unblocking fluid used organic acids formic acid and ammonium fluoride, which are relatively weakly acidic, have a slow reaction rate, and generally achieve only moderate modification effects. Core 1 used conventional temporary plugging and acidizing modification measures, while core 2 used the integrated shale oil reservoir unblocking agent of this invention. The modification efficiency of core 2 was 2.45 times that of core 1.

[0119] The above embodiments demonstrate that the integrated shale oil reservoir unblocking agent of the present invention can achieve better transformation effects than conventional acidizing when applied to relevant reservoirs, and is convenient to construct, with broad application prospects.

[0120] The above description is merely a specific embodiment of the present invention. Any feature disclosed in this specification may be replaced by other equivalent or similar features unless otherwise specified. All features or steps in the disclosed methods or processes may be combined in any way, except for mutually exclusive features and / or steps.

Claims

1. An integrated unblocking agent for shale oil reservoirs, characterized in that: consists of the following components by weight parts: 30-50 parts of inorganic plugging solution, 10-30 parts of organic plugging solution, 10-30 parts of degradable suspended gel ball, 3-10 parts of oil-water dispersing agent.

2. The shale oil reservoir integrated plugging agent and plugging method according to claim 1, characterized in that: The total amount of the inorganic plugging solution is 100 parts, and specifically consists of the following components by weight parts: 5-20 parts of acid, 1-5 parts of fluoride-containing acid / salt, 3-5 parts of chelating agent, 1-5 parts of corrosion inhibitor, 1-5 parts of clay stabilizer, and the rest is water.

3. The shale oil reservoir integrated plugging agent and plugging method according to claim 2, characterized in that: The acid is one or a mixture of several kinds of hydrochloric acid, formic acid, acetic acid, and sulfamic acid in any ratio; The fluoride-containing acid / salt is one or a mixture of several kinds of hydrofluoric acid, fluoroboric acid, and ammonium fluoride in any ratio; The chelating agent is one or a mixture of several kinds of EDTA, EDTA.2Na, EDTA.4Na, DTPA, HEDTA, NTA, EGTA, ATMP, HEDP, EDTMP, DTPMP, ATP, and HPMA in any ratio; The corrosion inhibitor is one or a mixture of several kinds of mercaptan, polyethylene glycol ether, sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate, diethylene triamine, hexamethylene tetramine, butynyl ethanol, butynyl glycol, imidazoline oleic acid, 4-methyl pyridine, and 4-vinyl pyridine in any ratio; The clay stabilizer is one or a mixture of several kinds of 2,3 epoxy propyl trimethyl ammonium chloride, γ-aminopropyl triethoxysilane, polydimethyl diallyl ammonium chloride, hexadecyl trimethyl ammonium chloride, and hexadecyl benzyl dimethyl ammonium chloride in any ratio.

4. The shale oil reservoir integrated plugging agent and plugging method according to claim 1, characterized in that: The organic plugging solution is a mixture of petroleum products and biological oil, and the total amount of the organic plugging solution is 100 parts, with the weight of the biological oil being 30-70 parts, and the rest being petroleum products; The petroleum product is one or a mixture of several kinds of diesel oil, kerosene, gasoline, and petroleum ether in any ratio; The biological oil is one or a mixture of several kinds of coconut oil, palm oil, and isopropyl myristate in any ratio.

5. The shale oil reservoir integrated plugging agent and plugging method according to claim 1, characterized in that: The degradable suspended gel ball consists of the following components by weight parts: 50-90 parts of water, 2-10 parts of degradable material, 0-1 part of toughening material, 5-20 parts of biological oil, 1-3 parts of oil-water dispersing agent, 0.1-1 part of inorganic salt, and 0-2 parts of acid regulator.

6. The shale oil reservoir integrated plugging agent and plugging method according to claim 5, characterized in that: The preparation method of the degradable suspended gel ball is as follows: S1: Add inorganic salt to water and stir until uniform, then add biological oil and 70-80% of the oil-water dispersing agent and stir until uniform, then add toughening material and stir until completely dissolved, then add degradable material and stir until uniform, and finally add acid regulator and stir until uniform to obtain the prepared glue solution; S2: Pour the glue solution into the forming liquid through a ball dropping machine, then filter the forming liquid to separate the gel ball; S3: Add 20-30% of the oil-water dispersing agent to the gel ball and stir until uniform, then place it in a curing tank and cure at 50-70°C for 3-10 minutes to obtain a degradable suspended gel ball with a particle size of 1-2 cm.

7. The shale oil reservoir integrated plugging agent and plugging method according to claim 5, characterized in that: The degradable material is one or a mixture of several kinds of agar, sodium alginate, pectin, and alginate propylene glycol ester in any ratio; The toughening material is one or a mixture of several kinds of xanthan gum, guar gum, gum arabic, polyacrylamide, and polyethylene glycol in any proportion; The inorganic salt is one or a mixture of several kinds of calcium carbonate, calcium lactate, ferrous chloride, ferrous oxide, dolomite, and limestone in any proportion; The acid regulator is one or a mixture of several kinds of citric acid, sodium citrate, gluconolactone, ammonium chloride, acetic acid, and sodium acetate in any proportion.

8. The shale oil reservoir integrated plugging agent and plugging method according to claim 1, characterized in that: The preparation method of the oil-water dispersant is as follows: M1: add an acid anhydride, biological oil, mutual solvent, and polyol into a reaction container at room temperature, stir under the condition of nitrogen, heat to 200-230℃, and react for 2-6h to obtain an intermediate product; M2: add the intermediate product into polyether polyol, add an alkaline regulator, stir for 30min under the condition of nitrogen, then add a catalyst under the protection of nitrogen and stir uniformly, heat to 150-180℃, and react for 3-5h to obtain the oil-water dispersant.

9. The shale oil reservoir integrated plug breaking agent and method of claim 1, wherein: The acid anhydride is one of succinic anhydride, maleic anhydride, and fumaric anhydride; The polyol is one or a mixture of several kinds of ethylene glycol, glycerol, pentaerythritol, polytetrahydrofuran diol, polyoxytetramethylene glycol, and ethylene glycol in any proportion; The mutual solvent is ethylene glycol butyl ether; The catalyst is one of dibutyl tin dilaurate and stannous octoate; The alkaline regulator is one of sodium bicarbonate, sodium hydroxide, and ammonia.

10. A method of integrated plug removal for a shale oil reservoir, the method comprising: The plugging removal process is as follows: ​ The inorganic plugging removal liquid is used as A agent, the oil-water dispersant and the organic plugging removal liquid are stirred uniformly to obtain B agent, the degradable suspended gel ball is used as C agent, A agent, B agent, and C agent are mixed and stirred uniformly, and then injected into the formation.