Emulsifying wetting agent, non-water-based drilling fluid containing emulsifying wetting agent and preparation method

Abstract

The invention belongs to the technical field of petroleum drilling, and relates to an emulsifying wetting agent, a non-water-based drilling fluid containing the emulsifying wetting agent and a preparation method of the non-water-based drilling fluid. The structural formula of the emulsion wetting agent provided by the invention is as follows: R1O (CR2HCH2O) aCH2CONH (CH2CH2NH) bR3, and / or R1O (CR2HCH2O) aCH2COOR4, and the structural formula of the emulsion wetting agent is as follows: R1O (CR2HCH2O) aCH2COOR4, wherein a is an integer from 1 to 10, and b is an integer from 1 to 4; r1 is a saturated or unsaturated, linear or branched, substituted or unsubstituted hydrocarbyl group having 6 to 18 carbon atoms; r2 is selected from one or more of H <-> and CH3 <->; r3 is selected from one or more of H <-> and-CH2CH2NH2; r < 4 > is selected from one or more of CH < 3->,-CH2CH3,-CH2CH2CH3,-CH < 2 > (CH3) 2,-CH2CH2CH2CH3,-CH2CH2CH < 3 >,-CH < 2 > (CH3) 2,-CH2CH2OH (OH) CH2 (OH). The emulsifying and wetting agent provided by the invention has relatively strong emulsifying capacity, wetting capacity and high-temperature resistance, and the non-water-based drilling fluid prepared from the emulsifying and wetting agent has excellent high-temperature emulsion resistance stability.

Description

Technical Field

[0001] This invention belongs to the field of petroleum drilling technology, and relates to an emulsified wetting agent and a non-water-based drilling fluid containing the same and a preparation method thereof, particularly to an emulsified wetting agent for non-water-based drilling fluid and a high-temperature, high-density non-water-based drilling fluid and a preparation method thereof. Background Technology

[0002] Drilling fluid is an indispensable circulating fluid in the drilling process. During drilling, it plays multiple roles, including carrying rock cuttings, cooling and lubricating the drill bit and drill string, maintaining wellbore stability, and balancing formation pressure. It is often referred to as the "blood" of drilling and is crucial to the success of drilling operations.

[0003] In oil exploration and development in high-temperature and high-pressure operating areas, the high formation temperature, high formation pressure, and long operating time present significant challenges to drilling operations and drilling fluid technology. Drilling fluid systems are required to possess properties such as high-temperature stability, rheological stability under high solids content, and sedimentation stability.

[0004] Non-water-based drilling fluids are drilling fluids that do not use water as a dispersion medium, and primarily use mineral oil, synthetic oil, or other organic liquids as the continuous phase. They are typically water-in-oil reverse emulsion drilling fluids, using inorganic salt aqueous solutions or organic salt aqueous solutions as the dispersed phase.

[0005] The technical challenge of developing high-temperature, high-density non-aqueous drilling fluids lies in the oil-water emulsion stability and solid-liquid interface adsorption stability of water-in-oil reverse emulsion drilling fluids under high-temperature, high-solids-content conditions. The temperature stability, emulsion stability, and anti-settling stability of high-temperature, high-density non-aqueous drilling fluids primarily depend on the temperature stability of the surfactants used in non-aqueous drilling fluids, as well as their adsorption and desorption stability at the oil-water and liquid-solid interfaces.

[0006] When the stability of high-temperature, high-density non-aqueous drilling fluid oil-water emulsions is insufficient, aqueous droplets aggregate and merge due to the destruction of the interfacial film at high temperatures, eventually separating from the oil phase. High temperatures deactivate interfacial active materials, leading to poor dispersion of aqueous droplets and potentially causing abnormal drilling fluid viscosity and shear stress. When the adsorption stability of the solid-liquid interface in high-temperature, high-density non-aqueous drilling fluid is insufficient, solid particles aggregate into large particles due to van der Waals forces, eventually settling. Macroscopically, this manifests as "sand settling" at the bottom of the drilling fluid and a decrease in density at the top. Summary of the Invention

[0007] To address the problems of poor temperature stability, emulsion stability, and anti-settling stability of non-water-based drilling fluids in high-temperature and high-pressure drilling operations in existing technologies, this invention provides an emulsified wetting agent, a non-water-based drilling fluid containing the same, and a preparation method thereof.

[0008] Specifically, in a first aspect, the present invention provides an emulsified wetting agent with the following structural formula:

[0009] R 1 O(CR 2 HCH2O) a CH2CONH(CH2CH2NH) b R 3 , and / or

[0010] R 1 O(CR 2 HCH2O) a CH2COOR 4 ;

[0011] Where a is an integer from 1 to 10, and b is an integer from 1 to 4;

[0012] R 1 It is a saturated or unsaturated, straight or branched, substituted or unsubstituted hydrocarbon group having 6 to 18 carbon atoms;

[0013] R 2 Selected from one or more of H- and CH3-;

[0014] R 3 Selected from one or more of H- and -CH2CH2NH2;

[0015] R 4 It is selected from one or more of CH3-, -CH2CH3, -CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH2CH3, -CH2CH2CH(CH3)2, -CH2CH2OH, and -CH2CH(OH)CH2(OH).

[0016] Of the above-mentioned emulsifying wetting agents, a is 2–6; b is 1–3; R 1 It is a straight-chain or monounsaturated hydrocarbon group with 16 to 18 carbon atoms; R 2 For H; R 3 For H- or -CH2CH2NH2; R 4 It is one or more of -CH2CH3, -CH(CH3)2, -CH2CH2OH, and -CH2CH(OH)CH2OH.

[0017] Secondly, the present invention also provides a method for preparing the above-mentioned emulsifying wetting agent, which is prepared by a dehydration condensation reaction of fatty alcohol polyoxyalkylene ether carboxylic acid and polyethylene polyamine or alcohol.

[0018] The preparation method of the above-mentioned emulsified wetting agent includes the following steps:

[0019] (1) Add 55 to 85 parts by weight of fatty alcohol polyoxyalkylene ether carboxylic acid to the reactor, add 0.001 to 0.003 parts by weight of catalyst, and purge with nitrogen for 0.5 to 1 hour to remove air from the reactor.

[0020] (2) Heat the reactor to 150℃ to 200℃ at a rotation speed of 200 to 600 rpm;

[0021] (3) Slowly add 10-45 parts by weight of polyethylene polyamine to the reaction vessel and react for 2-8 hours. Stop the reaction when the acid value is lower than 10 mg KOH / g to obtain the emulsified wetting agent.

[0022] The preparation method of the above-mentioned emulsified wetting agent includes the following steps:

[0023] (1) Add 40-85 parts by weight of fatty alcohol polyoxyalkylene ether carboxylic acid to the reactor and purge with nitrogen for 0.5-1 hour to remove air from the reactor.

[0024] (2) Add 20-60 parts by weight of alcohol and 0.005-0.015 parts by weight of catalyst, and heat the reactor to 70℃-100℃ at a speed of 200-600 rpm, and reflux for 2-8 hours until the acid value is lower than 10 mg KOH / g.

[0025] (3) Heat the reactor to 105-150°C and recover the alcohol until the amount of recovered alcohol no longer increases, thus obtaining the emulsified wetting agent.

[0026] In the above-described method for preparing the emulsifying wetting agent, the fatty alcohol polyoxyalkylene ether carboxylic acid has the following structural formula: R 1 O(CR 2 HCH2O) a CH2COOH;

[0027] Where a is an integer from 1 to 10; R 1 It is a saturated or unsaturated, straight or branched, substituted or unsubstituted hydrocarbon group having 6 to 18 carbon atoms; R 2 Selected from one or more of H- and CH3-.

[0028] In the above-mentioned method for preparing the emulsifying wetting agent, the polyethylene polyamine includes one or more of ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine.

[0029] In the above-mentioned method for preparing the emulsifying wetting agent, the alcohol includes one or more of methanol, ethanol, propanol, isopropanol, ethylene glycol, glycerol, isoamyl alcohol, and 1-pentanol.

[0030] Thirdly, the present invention also provides a non-water-based drilling fluid, comprising: the emulsified wetting agent described above or the emulsified wetting agent prepared by the above preparation method, base oil, aqueous phase, emulsifier, viscosity modifier, shearing agent, filtration loss reducer, alkalinity modifier, and weighting agent.

[0031] The aforementioned non-water-based drilling fluid, with a total volume of base oil and aqueous phase of 100 mL, includes: 70 to 95 mL base oil, 5 to 30 mL aqueous phase, 3 g to 6 g emulsifier, 1 g to 5 g emulsifying wetting agent, 0.25 g to 2 g viscosity modifier, 1 g to 5 g shearing agent, 2 g to 8 g filtration loss reducer, 2 g to 4 g alkalinity modifier, and 1089 g to 3733 g weighting agent.

[0032] The aforementioned non-water-based drilling fluid includes base oil comprising any one or more of diesel, white oil, and gas-derived oil; the aqueous phase is an inorganic salt solution or an organic salt solution with a solute mass fraction of 20 wt% to 40 wt%.

[0033] The emulsifier in the aforementioned non-water-based drilling fluid includes any one or more of fatty acid polyamide emulsifiers; the viscosity modifier is organic clay.

[0034] The aforementioned non-water-based drilling fluid includes, but is not limited to, a cutting agent comprising one or more of vegetable oleic acid and vegetable oleic acid dimer; and a filtration loss reducer selected from any one or more of organic amine-modified humic acid, oxidized asphalt, and sulfonated asphalt with a carbon number of twelve to eighteen.

[0035] The above-mentioned non-water-based drilling fluid includes, as a result, any one or both of calcium oxide and calcium hydroxide as an alkalinity adjuster; and any one or more of barite, limestone powder, galena powder, and manganese ore powder as a weighting agent.

[0036] The aforementioned non-water-based drilling fluid has a density of 1.8 g / cm³. 3 ~2.5g / cm 3 .

[0037] Fourthly, the present invention also provides a method for preparing the above-mentioned non-water-based drilling fluid, comprising:

[0038] (1) Add the emulsifier and the wetting agent to the base oil and stir to mix;

[0039] (2) Add the viscosity modifier, shearing agent and alkalinity modifier, and stir to mix;

[0040] (3) Add the aqueous phase and stir to mix;

[0041] (4) Add the filtration loss reducer and stir to mix;

[0042] (5) Add the weighting agent and stir to adjust the density of the drilling fluid to the desired value to obtain the non-water-based drilling fluid.

[0043] In the above-mentioned method for preparing non-water-based drilling fluid, in steps (1) to (4), the stirring and mixing time is 5 min to 30 min, and the stirring and mixing speed is 8000 rpm to 12000 rpm.

[0044] The technical solution of the present invention has the following beneficial effects:

[0045] (1) The non-water-based drilling fluid of the present invention is a high-temperature and high-density non-water-based drilling fluid that has good rheological properties and anti-settling stability under high temperature and high solid content conditions.

[0046] (2) The emulsifying wetting agent provided by the present invention has strong emulsifying ability, wetting ability and high temperature resistance. The non-water-based drilling fluid prepared by it has excellent high temperature emulsion stability.

[0047] (3) The emulsified wetting agent provided by the present invention can be adsorbed on the surface of inferior contaminated soil, changing the wetting properties of the surface, so that the non-water-based drilling fluid system has better rheological properties and resistance to inferior solid phase pollution. Attached Figure Description

[0048] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention.

[0049] Figure 1 Infrared spectrum of the emulsified wetting agent prepared in Example 1;

[0050] Figure 2 The infrared spectrum of the emulsified wetting agent prepared in Example 2;

[0051] Figure 3 Infrared spectrum of the emulsified wetting agent prepared in Example 3;

[0052] Figure 4 The infrared spectrum of the emulsified wetting agent prepared in Example 4;

[0053] Figure 5 Infrared spectrum of the emulsified wetting agent prepared in Example 5;

[0054] Figure 6 The infrared spectrum of the emulsified wetting agent prepared in Example 6. Detailed Implementation

[0055] To fully understand the purpose, features, and effects of this invention, the following detailed embodiments are provided. Except as described below, the process methods of this invention employ conventional methods or apparatus in the art. Unless otherwise specified, the terms and expressions used below have the meanings commonly understood by those skilled in the art.

[0056] Specifically, this invention provides two emulsifying wetting agents, the structural formulas of which are as follows:

[0057] R 1 O(CR 2 HCH2O) a CH2CONH(CH2CH2NH) b R 3 , and / or

[0058] R 1 O(CR 2 HCH2O) a CH2COOR 4 ;

[0059] Where a is an integer from 1 to 10, and b is an integer from 1 to 4; R 1 It is a saturated or unsaturated, straight or branched, substituted or unsubstituted hydrocarbon group having 6 to 18 carbon atoms; R 2 Selected from one or more of H- and CH3-; R 3 Selected from one or more of H- and -CH2CH2NH2; R 4 It is selected from one or more of CH3-, -CH2CH3, -CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH2CH3, -CH2CH2CH(CH3)2, -CH2CH2OH, and -CH2CH(OH)CH2(OH).

[0060] The emulsifying wetting agent of this invention provides oil-phase affinity through long-chain alkyl groups, regulates hydrophilicity through polyoxyethylene segments, and enhances interfacial adsorption and toughness through polar head groups and polyamine structures. Combined with its stable covalent bond structure, it collectively endows the agent with strong emulsifying, wetting, and high-temperature resistance capabilities. This molecular design effectively solves the problems of emulsion stability, solid-liquid dispersion, and anti-settling stability of non-water-based drilling fluids under high-temperature and high-density conditions. It can remain stable at 180–200℃ and has significant application value.

[0061] In some preferred embodiments, a is 2 to 6; b is 1 to 3; R 1 It is a straight-chain or monounsaturated hydrocarbon group with 16 to 18 carbon atoms; R 2 For H; R 3 For H- or -CH2CH2NH2; R 4It is one or more of -CH2CH3, -CH(CH3)2, -CH2CH2OH, and -CH2CH(OH)CH2OH.

[0062] Wherein, the structural formula is R 1 O(CR 2 HCH2O) a CH2CONH(CH2CH2NH) b R 3 The emulsifying wetting agent is prepared by the dehydration condensation reaction of fatty alcohol polyoxyalkylene ether carboxylic acid and polyethylene polyamine. Specifically, the preparation method is as follows:

[0063] (1) Add 55 to 85 parts by weight of fatty alcohol polyoxyalkylene ether carboxylic acid to the reactor, add 0.001 to 0.003 parts by weight of catalyst, and purge with nitrogen for 0.5 to 1 hour to remove air from the reactor.

[0064] (2) Heat the reactor to 150℃ to 200℃ at a rotation speed of 200 to 600 rpm;

[0065] (3) Slowly add 10-45 parts by weight of polyethylene polyamine to the reaction vessel and react for 2-8 hours. Stop the reaction when the acid value is lower than 10 mg KOH / g to obtain the emulsified wetting agent.

[0066] During the preparation process, fatty alcohol polyoxyalkylene ether carboxylic acid and polyethylene polyamine undergo a dehydration condensation reaction under the catalysis of a catalyst to generate amide bonds and release water molecules.

[0067] In some preferred embodiments, the fatty alcohol polyoxyalkylene ether carboxylic acid has the following structural formula: R 1 O(CR 2 HCH2O) a CH2COOH; where a is an integer from 1 to 10; R 1 It is a saturated or unsaturated, straight or branched, substituted or unsubstituted hydrocarbon group having 6 to 18 carbon atoms; R 2 Selected from one or more of H- and CH3-.

[0068] In some preferred embodiments, the polyethylene polyamine includes one or more of ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine.

[0069] In some preferred embodiments, the catalyst is potassium hydroxide or sodium hydroxide.

[0070] Wherein, the structural formula is R 1 O(CR 2 HCH2O) a CH2COOR 4The emulsifying wetting agent is prepared by the dehydration condensation reaction of fatty alcohol polyoxyalkylene ether carboxylic acid and alcohol. The specific preparation method is as follows:

[0071] (1) Add 40-85 parts by weight of fatty alcohol polyoxyalkylene ether carboxylic acid to the reactor and purge with nitrogen for 0.5-1 hour to remove air from the reactor.

[0072] (2) Add 20-60 parts by weight of alcohol and 0.005-0.015 parts by weight of catalyst, and heat the reactor to 70℃-100℃ at a speed of 200-600 rpm, and reflux for 2-8 hours until the acid value is lower than 10 mg KOH / g.

[0073] (3) Heat the reactor to 105-150°C and recover the alcohol until the amount of recovered alcohol no longer increases, thus obtaining the emulsified wetting agent.

[0074] During the preparation process, fatty alcohol polyoxyalkylene ether carboxylic acid and alcohol undergo esterification reaction under the action of acidic catalyst to generate ester bonds and release water molecules.

[0075] In some preferred embodiments, the fatty alcohol polyoxyalkylene ether carboxylic acid has the following structural formula: R 1 O(CR 2 HCH2O) a CH2COOH; where a is an integer from 1 to 10; R 1 It is a saturated or unsaturated, straight or branched, substituted or unsubstituted hydrocarbon group having 6 to 18 carbon atoms; R 2 Selected from one or more of H- and CH3-.

[0076] In some preferred embodiments, the alcohol includes one or more of methanol, ethanol, propanol, isopropanol, ethylene glycol, glycerol, isoamyl alcohol, and 1-pentanol.

[0077] In some preferred embodiments, the catalyst is p-toluenesulfonic acid.

[0078] On the other hand, the present invention also provides a non-water-based drilling fluid comprising the above-mentioned emulsified wetting agent. The emulsified wetting agent comprises 0.5% to 5% by weight in the non-water-based drilling fluid.

[0079] In some preferred embodiments, the non-water-based drilling fluid provided by the present invention includes an emulsifying wetting agent, base oil, aqueous phase, emulsifier, viscosity modifier, shearing agent, filtration loss reducer, alkalinity modifier, and weighting agent.

[0080] Emulsified wetting agents can synergistically work with other functional components in non-water-based drilling fluid systems to form stable adsorption films at the oil-water and solid-liquid interfaces, improving the interfacial properties and dispersion of solid particles. This allows them to maintain good rheological and emulsion stability under high temperature and high pressure conditions, and effectively inhibit solid sedimentation and stratification. At the same time, by promoting the dispersion and action of other additives, emulsified wetting agents further improve the overall temperature stability, emulsion stability, and anti-settling performance of drilling fluids.

[0081] Specifically, in non-water-based drilling fluids, emulsifying wetting agents work synergistically with emulsifiers and alkalinity regulators to form a stable interfacial film at the oil-water interface, improving the stability of the emulsion at high temperatures; they also work synergistically with viscosity modifiers, shearing agents, and weighting agents to improve the wettability of solid particles and enhance the suspension capacity of the system, thereby effectively preventing sedimentation and stratification; and they work synergistically with filtration loss reducers to promote the formation of a dense filter cake on the wellbore surface and maintain the stability of the adsorption structure at the solid-liquid interface, thereby comprehensively improving the drilling fluid's temperature stability, emulsion stability, and anti-settling performance.

[0082] In a further preferred embodiment, based on a total volume of 100 mL of base oil and aqueous phase, the emulsifying wetting agent comprises 1 g to 5 g, the base oil comprises 70 to 95 mL, the aqueous phase comprises 5 to 30 mL, the emulsifier comprises 3 g to 6 g, the viscosity modifier comprises 0.25 g to 2 g, the shearing agent comprises 1 g to 5 g, the filtration loss reducer comprises 2 g to 8 g, the alkalinity modifier comprises 2 g to 4 g, and the weighting agent comprises 1089 g to 3733 g.

[0083] In some preferred embodiments, the base oil includes any one or more of diesel oil, white oil, and gas-derived oil.

[0084] In some preferred embodiments, the aqueous phase is an inorganic salt solution or an organic salt solution with a solute mass fraction of 20 wt% to 40 wt%. Optionally, the inorganic salt solution or organic salt solution is selected from any one or more of calcium chloride aqueous solution, sodium chloride aqueous solution, potassium chloride aqueous solution, calcium formate aqueous solution, calcium acetate aqueous solution, sodium formate aqueous solution, sodium acetate aqueous solution, potassium formate aqueous solution, and potassium acetate aqueous solution.

[0085] In some preferred embodiments, the emulsifier includes any one or more of fatty acid polyamide emulsifiers, optionally selected from any one or more of tall oil fatty acid polyamide, oleic acid polyamide and stearic acid polyamide.

[0086] In some preferred embodiments, the viscosity modifier is an organoclay, optionally selected from any one or more of long-chain quaternary ammonium salt modified sodium-based bentonite, wherein the long chain has twelve, fourteen, sixteen, and eighteen carbon atoms, and the number of long chains is one or two.

[0087] In some preferred embodiments, the cutting agent includes one or more of oleic acid and oleic acid dimer.

[0088] In some preferred embodiments, the filtration loss reducing agent is selected from any one or more of organic amine-modified humic acid, oxidized asphalt, and sulfonated asphalt having a carbon number of twelve to eighteen. Optionally, the organic amine in the organic amine-modified humic acid has a carbon number of fourteen, sixteen, or eighteen.

[0089] In some preferred embodiments, the alkalinity regulator includes any one or both of calcium oxide and calcium hydroxide.

[0090] In some preferred embodiments, the weighting agent includes any one or more of barite, limestone powder, galena powder, and manganese ore powder.

[0091] The non-water-based drilling fluid preparation method provided by this invention is simple to operate; it only requires mixing the components evenly according to the specified ratio and order.

[0092] In some preferred embodiments, the method for preparing non-water-based drilling fluid provided by the present invention includes: (1) adding the emulsifier and the wetting agent to the base oil and stirring to mix; (2) adding the viscosity modifier, the shearing agent and the alkalinity modifier and stirring to mix; (3) adding the aqueous phase and stirring to mix; (4) adding the filtration loss reducer and stirring to mix; (5) adding the weighting agent and stirring to adjust the density of the drilling fluid to the desired value, thereby obtaining the non-water-based drilling fluid.

[0093] In steps (1) to (4), the stirring and mixing time is 5 min to 30 min, and the stirring and mixing speed is 8000 rpm to 12000 rpm.

[0094] The non-water-based drilling fluid prepared according to the method of the present invention has a density of 1.8 g / cm³. 3 ~2.5g / cm 3 .

[0095] Through practice, the emulsified wetting agent designed in this invention has good temperature stability and adsorption stability, which can effectively alleviate the problems of temperature stability, emulsion stability and anti-settling stability faced by non-water-based drilling fluids under high temperature and high solid content conditions.

[0096] Example

[0097] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments, unless otherwise specified, are performed according to conventional methods and conditions.

[0098] The raw materials used in the following examples are from the following sources:

[0099] C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid: Sasol (China) Chemical Co., Ltd.;

[0100] Isomeric C13 fatty alcohol polyoxyalkylene ether carboxylic acid: Sasol (China) Chemical Co., Ltd.;

[0101] Tall oil fatty acid polyamide: Blue Ocean Boda Technology Co., Ltd., high-temperature emulsifier EMULHT for oil-based drilling fluids;

[0102] Alkyl quaternary ammonium salt modified organobentonite: Zhejiang Fenghong New Material Co., Ltd., organobentonite FHD-150;

[0103] Organic amine modified humic acid: Kaiping Lianji Chemical Co., Ltd., TP-L3

[0104] Example 1

[0105] The emulsified wetting agent is prepared according to the composition in Table 1, including the following steps:

[0106] 100g of C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid was added to a reaction vessel, along with 0.2g of potassium hydroxide. Nitrogen gas was purged for 0.5h to purge air from the reaction vessel. The reaction vessel was then heated to 160℃ at 600 rpm. 20g of diethylenetriamine was slowly added dropwise to the reaction vessel, and the reaction was carried out for 5h under nitrogen protection at 160℃ and stirring at 600 rpm. The reaction continued until the acid value decreased to below 10mg KOH / g. The reaction product was then cooled to room temperature to obtain the emulsified wetting agent. The infrared spectrum of the obtained emulsified wetting agent is shown below. Figure 1 .

[0107] Depend on Figure 1 It can be seen that the C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid and diethylenetriamine successfully underwent an amidation reaction. This was observed as the characteristic peak of the raw material carboxylic acid (approximately 1730 cm⁻¹). -1 The characteristic peaks of amide I / II disappeared, and the peaks at 1659.60 / 1540.16 cm⁻¹ disappeared. -1 ) appears, while polyoxyethylene ether (1099.39cm) is retained. -1 ) and alkyl chains (2921.84 / 2852.71 / 1456.14 / 1372.81 / 842.01 / 720.28cm) -1 Infrared spectral characteristics of the structure.

[0108] Example 2

[0109] The emulsified wetting agent is prepared according to the composition in Table 1, including the following steps:

[0110] 100g of isomeric C13 fatty alcohol polyoxyalkylene ether carboxylic acid was added to a reaction vessel, along with 0.2g of potassium hydroxide. Nitrogen gas was purged for 0.5h to purge air from the reaction vessel. The reaction vessel was then heated to 160℃ at 600 rpm. 20g of diethylenetriamine was slowly added dropwise to the reaction vessel, and the reaction was carried out for 5h under nitrogen protection at 160℃ and stirring at 600 rpm. The reaction continued until the acid value decreased to below 10mg KOH / g. The reaction product was then cooled to room temperature to obtain the emulsified wetting agent. The infrared spectrum of the obtained emulsified wetting agent is shown below. Figure 2 .

[0111] Depend on Figure 2 It can be seen that the isomer of C13 fatty alcohol polyoxyalkylene ether carboxylic acid successfully underwent an amidation reaction with diethylenetriamine. This was observed as the characteristic peak of the starting carboxylic acid (approximately 1730 cm⁻¹). -1 The characteristic peaks of amide I / II disappeared, and the peaks at 1668.60 and 1537.35 cm⁻¹ disappeared. -1 ) appears, while polyoxyethylene ether (1097.61cm) is retained. -1 ) and alkyl chains (2955.68 / 2921.54 / 2859.64 / 1456.85 / 1374.01 / 848.49cm) -1 Infrared spectral characteristics of the structure.

[0112] Example 3

[0113] The emulsified wetting agent is prepared according to the composition in Table 1, including the following steps:

[0114] 100g of C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid was added to a reaction vessel, along with 0.3g of potassium hydroxide. Nitrogen gas was purged for 0.5h to purge air from the reaction vessel. The reaction vessel was then heated to 180℃ at 600 rpm. 40g of triethylenetetramine was slowly added dropwise to the reaction vessel, and the reaction was carried out for 5h under nitrogen protection at 180℃ and stirring at 600 rpm. The reaction continued until the acid value decreased to below 10mg KOH / g. The reaction product was then cooled to room temperature to obtain the emulsified wetting agent. The infrared spectrum of the obtained emulsified wetting agent is shown below. Figure 3 .

[0115] Depend on Figure 3 It can be seen that the C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid and tetraethylenepentamine successfully underwent an amidation reaction. This was observed as a characteristic peak of the raw material carboxylic acid (approximately 1730 cm⁻¹). -1 The characteristic peaks of amide I / II disappeared (1667.30 / 1539.65cm). -1 ) appears, while polyoxyethylene ether (1101.12cm) is retained. -1) and alkyl chains (2921.94 / 2852.44 / 1456.22 / 1372.70 / 842.28 / 720.86cm) -1 Infrared spectral characteristics of the structure.

[0116] Example 4

[0117] The emulsified wetting agent is prepared according to the composition in Table 2, including the following steps:

[0118] 100g of C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid was added to a reaction vessel, and nitrogen gas was purged for 0.5h to purge air from the reaction vessel. 50g of isopropanol and 1.2g of p-toluenesulfonic acid were added, and the reaction vessel was heated to 88℃ at 600 rpm. The mixture was then refluxed at 600 rpm for 5h with stirring until the acid value decreased to below 10mg KOH / g. The reaction vessel was then heated to 105℃ to recover the alcohol until the amount of recovered alcohol no longer increased. The reaction product was cooled to room temperature to obtain an emulsified wetting agent. The infrared spectrum of the emulsified wetting agent is shown below. Figure 4 .

[0119] Depend on Figure 4 It can be seen that the C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid and isopropanol successfully underwent an esterification reaction. This was observed as the characteristic peak of the raw material carboxylic acid (approximately 1730 cm⁻¹). -1 The peak disappeared, and the characteristic peak of the ester structure (1748.03 cm⁻¹) was also observed. -1 ) appears, while retaining polyoxyethylene ether (1100.66cm) -1 ) and alkyl chains (2922.23 / 2853.03 / 1456.48 / 1373.70 / 1347.72 / 850.76 / 721.47cm) -1 Infrared spectral characteristics of the structure.

[0120] Example 5

[0121] The emulsified wetting agent is prepared according to the composition in Table 2, including the following steps:

[0122] 100g of isomeric C13 fatty alcohol polyoxyalkylene ether carboxylic acid was added to a reaction vessel, and nitrogen gas was purged for 0.5h to purge air from the vessel. 75g of isopropanol and 1.2g of p-toluenesulfonic acid were added, and the reaction vessel was heated to 88℃ at 600 rpm. The mixture was then refluxed at 600 rpm for 5h with stirring until the acid value decreased to below 10mg KOH / g. The reaction vessel was then heated to 105℃ to recover the alcohol until the amount of recovered alcohol no longer increased. The reaction product was cooled to room temperature to obtain the emulsified wetting agent. The infrared spectrum of the emulsified wetting agent is shown below. Figure 5 .

[0123] Depend on Figure 5 It can be seen that the isomeric C13 fatty alcohol polyoxyalkylene ether carboxylic acid and isopropanol successfully underwent an esterification reaction. This was observed as the characteristic peak of the starting carboxylic acid (approximately 1730 cm⁻¹). -1 The peak disappeared, and the characteristic peak of the ester structure (1747.81 cm⁻¹) was observed. -1 ) appears, while polyoxyethylene ether (1100.23cm) is retained. -1 ) and alkyl chains (2957.27 / 2923.00 / 2868.59 / 1456.78 / 1374.40 / 849.32cm) -1 Infrared spectral characteristics of the structure.

[0124] Example 6

[0125] The emulsified wetting agent is prepared according to the composition in Table 2, including the following steps:

[0126] 100g of C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid was added to a reaction vessel, and nitrogen gas was purged for 0.5h to purge air from the reaction vessel. 50g of isoamyl alcohol and 1.5g of p-toluenesulfonic acid were added, and the reaction vessel was heated to 138℃ at 600 rpm. The mixture was then refluxed for 5h under stirring at 600 rpm until the acid value decreased to below 10mg KOH / g. The reaction vessel was then heated to 142℃ to recover the alcohol until the amount of recovered alcohol no longer increased. The reaction product was cooled to room temperature to obtain the emulsified wetting agent. The infrared spectrum of the emulsified wetting agent is shown below. Figure 6 .

[0127] Depend on Figure 6 It can be seen that the C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid and isoamyl alcohol successfully underwent an esterification reaction. This is characterized by the characteristic peak of the raw material carboxylic acid (approximately 1730 cm⁻¹). -1 The peak disappeared, and the characteristic peak of the ester structure (1755.06 cm⁻¹) was lost. -1 ) appears, while polyoxyethylene ether (1103.99cm) is retained. -1 ) and alkyl chains (2923.04 / 2854.31 / 1463.63 / 1373.16 / 836.67 / 720.88cm) -1 Infrared spectral characteristics of the structure.

[0128] Comparative Example 1

[0129] Comparative Example 1 was tested for both emulsification efficiency and wetting efficiency as follows: it contained only base oil and the corresponding necessary inorganic salts / solid phase, and no emulsifying wetting agents; the other operating conditions were consistent with the test method, and it was used as a blank control.

[0130] Comparative Example 1 used for emulsification rate evaluation consisted of 250 mL white oil + 9.0 g calcium hydroxide + 50 mL of 26% CaCl2 solution.

[0131] Comparative Example 1 used for wetting efficiency evaluation: 10 mL base oil + 2.0 g (dried at 105℃) barite.

[0132] Comparative Example 2

[0133] The emulsifying wetting agent is tall oil fatty acid.

[0134] Emulsification and wetting performance evaluation

[0135] The emulsifying and wetting properties of the emulsifying wetting agents prepared in Examples 1 to 6 were evaluated.

[0136] 1. Acid value test

[0137] Titration is one of the most commonly used methods for determining acid value. It determines the reaction progress and the content of carboxylate ions in the product by measuring the content of free fatty acids in the sample. The specific procedure involves dissolving the oil sample to be tested in ethanol or ether, adding phenolphthalein indicator, and titrating to the endpoint with standard sodium hydroxide solution to determine the amount of sodium hydroxide solution used and calculate the acid value. The specific test method for determining the acid value of the reaction product emulsion wetting agent adopts the method specified in the Chinese national standard "GB / T 9104-2022 Industrial Stearic Acid Test Methods Part 6 Determination of Acid Value". The acid value determination results of the emulsion wetting agents of Examples 1 to 6 and Comparative Examples 1-2 are shown in Table 1.

[0138] 2. Emulsification efficiency test

[0139] Emulsification efficiency typically refers to the ability to form a stable emulsion during the emulsification process, while emulsification stability refers to the ability of an emulsion to remain stable and not separate during storage. The volumetric method for oil-water separation is a direct and effective way to evaluate the emulsification efficiency of oil-water emulsions. By measuring the volume of oil-water separation under specific conditions, emulsification efficiency can be indirectly assessed. Emulsions with high emulsification efficiency separate smaller volumes of oil or water phases under the same conditions, indicating better stability. The specific test method is as follows:

[0140] (1) Preparation of 26% calcium chloride solution: Weigh 26g of calcium chloride and place it in a 100mL beaker. Measure 74mL of distilled water and add it to the beaker containing the calcium chloride solid. Stir to dissolve and set aside for later use.

[0141] (2) Take 250 mL of white oil into a high-speed stirring cup, add 6.0 g of sample, stir at 10000 RPM for 5 min, slowly add 9.0 g of calcium hydroxide, stir at 10000 RPM for 5 min, add 50 mL of 26% CaCl2 aqueous solution, stir at high speed for 20 min, put it into an aging tank and then put it into a roller furnace, roll it at 150℃ for 16 h (or 24 h), take it out and cool it to room temperature, stir at high speed for 20 min, pour it into the highest mark of a 250 mL graduated cylinder, let it stand and observe, and read the volume of the oil layer separated in 10 min.

[0142] (3) Calculate according to the formula

[0143]

[0144] Where: W1—Emulsification rate, %;

[0145] V – The volume of oil layer separated in 10 minutes, in mL.

[0146] The results of emulsification efficiency determination of the emulsifying wetting agents of Examples 1 to 6 and Comparative Examples 1-2 are shown in Table 1.

[0147] 3. Wetting efficiency test

[0148] The principle of colloidal sedimentation stability is a method for determining wetting efficiency. By observing changes in the sedimentation behavior of barite particles in a liquid medium, the wetting ability of corresponding emulsified wetting agents at the barite-oil phase solid-liquid interface is evaluated. The wetting performance of different emulsified wetting agents is evaluated by measuring the time required to separate 5 mL of clear oil phase. The specific test method for oil separation time is as follows:

[0149] (1) Weigh 50.0g (accurate to 0.01g) of barite sample and put it into an oven. Dry it at 105℃±0.1℃ for 120min. After drying, put it into a desiccator to cool and wait for use.

[0150] (2) Use a pipette to measure two 10 mL portions of base oil and pour them into two 50 mL beakers.

[0151] (3) Weigh 0.2g (accurate to 0.01g) of the sample, add it to one portion of the base oil, seal it with plastic wrap, and stir it with a magnetic stirrer at 500r / min for 10min to prepare a uniform oil solution.

[0152] (4) Weigh 2.0g (accurate to 0.01g) of dried barite in two portions, add them to the two beakers mentioned above, seal them with plastic wrap, and stir with a magnetic stirrer at 500r / min for 60min.

[0153] (5) Then quickly transfer them to two 10mL stoppered test tubes, place them in a 25℃ water bath and let them stand, and start timing at the same time.

[0154] (6) Read and record the time required for 5 mL of clear oil phase to be separated from the upper layer.

[0155] 4. Results and Discussion

[0156] The wetting efficiency test results of the emulsified wetting agents of Examples 1 to 6 and Comparative Examples 1-2 are shown in Table 1.

[0157] Table 1 Performance Evaluation of Emulsifiers

[0158]

[0159] The acid value of the C16-C18 fatty alcohol polyoxyalkylene ether carboxylic acid was 47.69 mg KOH / g. The acid value of the reaction product in Example 1 was 11.22 mg KOH / g, and the acid value of the reaction product in Example 3 was 3.49 mg KOH / g. The decrease in acid value indicates a reduction in free fatty acid content and the occurrence of the corresponding amidation reaction. The acid value of the reaction product in Example 4 was 19.64 mg KOH / g, and the acid value of the reaction product in Example 6 was 6.03 mg KOH / g. The decrease in acid value also indicates a reduction in free fatty acid content and the occurrence of the corresponding esterification reaction.

[0160] The acid value of the isomeric C13 fatty alcohol polyoxyalkylene ether carboxylic acid was 59.66 mg KOH / g. The acid value of the reaction product in Example 2 was 8.75 mg KOH / g, indicating a decrease in free fatty acid content and the occurrence of the corresponding amidation reaction. The acid value of the reaction product in Example 5 was 27.19 mg KOH / g, also showing a decrease, indicating a decrease in free fatty acid content and the occurrence of the corresponding esterification reaction.

[0161] The emulsification efficiencies of Examples 1-6 at 16h and 24h were higher than those of Comparative Examples 1 and 2, indicating that the reaction products have the effect of improving the interfacial stability of oil-water emulsions.

[0162] The oil separation time in Examples 1-6 was higher than that in Comparative Examples 1 and 2, indicating that the reaction product has the effect of improving the wetting stability of the solid-liquid interface.

[0163] Example 7

[0164] (1) Formulation of high-temperature, high-pressure anti-settling and stabilizing non-water-based drilling fluid (oil-water ratio of 90:10):

[0165] The base oil was gas-derived oil; the aqueous phase was a 25% CaCl2 aqueous solution; the emulsifier was tall oil fatty acid polyamide (Blue Ocean Boda Technology Co., Ltd., EMUL HT, a high-temperature emulsifier for oil-based drilling fluids); the emulsifying wetting agent was prepared in Example 1; the organoclay was alkyl quaternary ammonium salt modified organobentonite (Zhejiang Fenghong New Material Co., Ltd., organobentonite FHD-150); the shearing agent was dimer acid; the alkalinity regulator was calcium hydroxide; the filtration loss reducer was organic amine modified humic acid (Kaiping Lianji Chemical Co., Ltd., TP-L3); and the weighting agent was barite.

[0166] (2) Methods for preparing drilling fluid:

[0167] Add 16g tall oil fatty acid polyamide emulsifier and 8g emulsifying wetting agent to 360mL of gas-to-oil mixture, and stir at 12000rpm / min for 5min in a high-speed mixer; while stirring at high speed, add 2g organoclay, 8g dimer acid and 12g calcium hydroxide, and stir at high speed for 5min; continue stirring at high speed, add 40mL of 25% CaCl2 aqueous solution, and stir at high speed for 20min; then add 16g of filtration loss reducer, and stir at high speed for 5min; finally, add barite to bring the weight to 2.4g / cm³. 3 Stir at high speed for 20 minutes to obtain a non-water-based drilling fluid.

[0168] Example 8

[0169] The difference from Example 7 is that the emulsifying wetting agent was prepared in Example 4.

[0170] Example 9

[0171] The difference from Example 7 is that 8% calcium clay by mass volume was added to the system formulation to simulate the intrusion of high solid content during the drilling process and to evaluate the effect of the prepared emulsified wetting agent on the drilling fluid’s resistance to high solid contamination.

[0172] Example 10

[0173] The difference from Example 8 is that 8% calcium clay by mass volume was added to the system formulation to simulate the intrusion of high solid content during the drilling process and to evaluate the effect of the prepared emulsified wetting agent on the drilling fluid’s resistance to high solid contamination.

[0174] Comparative Example 3

[0175] The difference from Example 7 is that no emulsifying wetting agent is added.

[0176] Comparative Example 4

[0177] The difference from Example 8 is that no emulsifying wetting agent is added.

[0178] Drilling fluid performance evaluation:

[0179] The density of the drilling fluid was determined using the methods and instruments specified in the Chinese national standard "GB / T 16783.2-2012 Field Testing of Drilling Fluids for Petroleum and Natural Gas Industry - Part 2: Non-Water-Based Drilling Fluids".

[0180] The plastic viscosity of drilling fluid was determined using the methods and instruments specified in the Chinese national standard "GB / T 16783.2-2012 Field Testing of Drilling Fluids for Petroleum and Natural Gas Industry - Part 2: Non-Water-Based Drilling Fluids".

[0181] The dynamic shear force of the drilling fluid was determined using the methods and instruments specified in the Chinese national standard "GB / T 16783.2-2012 Field Testing of Drilling Fluids for Petroleum and Natural Gas Industry - Part 2: Non-Water-Based Drilling Fluids".

[0182] The demulsification voltage of drilling fluid was determined using the methods and instruments specified in the Chinese national standard "GB / T 16783.2-2012 Field Testing of Drilling Fluids for Petroleum and Natural Gas Industry - Part 2: Non-Water-Based Drilling Fluids".

[0183] The high-temperature high-pressure (HTHP) filtration loss of drilling fluid was determined using the methods and instruments specified in the Chinese national standard "GB / T 16783.2-2012 Field Testing of Drilling Fluids for Petroleum and Natural Gas Industry - Part 2: Non-water-based Drilling Fluids". The HTHP filtration loss was measured at a temperature of 176℃ and a pressure of 3.5 MPa.

[0184] The static settling stability of drilling fluid was evaluated using the static settling factor method. The test method for static settling stability was as follows: after the drilling fluid sample completed static aging in an aging tank, the density ρtop at the top of the column (below the free volume layer) and the density ρbottom at the bottom were measured. The static settling factor SF was calculated as follows:

[0185]

[0186] When SF is between 0.50 and 0.53, it indicates that no static settlement has occurred in the drilling fluid system; when SF is greater than 0.53, it indicates that static settlement has occurred.

[0187] The testing sequence is as follows: Before conducting the drilling fluid aging performance test, the rheological properties, electrical stability, and high-temperature and high-pressure filtration properties of the prepared drilling fluid are first tested. Then, the drilling fluid is placed in a high-temperature aging tank and aged at a set aging temperature of 180℃ for 72 hours. After cooling to 65℃, the performance of the drilling fluid after aging is tested.

[0188] The performance test results of the non-water-based drilling fluids in Examples 7 to 10 and Comparative Examples 3 to 4 before and after aging are shown in Tables 2 and 3, respectively.

[0189] Table 2 Performance of non-water-based drilling fluid system before aging

[0190]

[0191] Table 3 Performance of non-water-based drilling fluid system after 72 hours of static aging.

[0192]

[0193] As shown in Tables 2 and 3, the density of the high-temperature, high-pressure non-water-based drilling fluid obtained in Examples 7 and 8 of this invention reaches 2.4 g / cm³. 3 The aging temperature reached 200℃, classifying it as a high-temperature, high-pressure drilling fluid. The rheological properties of the high-temperature, high-pressure non-water-based drilling fluid remained relatively stable after standing at high temperature for 72 hours, without abrupt changes. It exhibited a high demulsification voltage (ES), low high-temperature, high-pressure filtration loss (HTHP), and a sedimentation factor (SF) of less than 0.53. This indicates that the emulsifying wetting agent in this embodiment effectively improved the oil wettability of the solid particles, allowing for good dispersion of the solid particles in the oil-water emulsion. In contrast, Comparative Example 3, lacking the self-made emulsifying wetting agent, experienced severe sedimentation after standing at high temperature for 72 hours.

[0194] Comparing Tables 2 and 3, it can be seen that the high-temperature, high-pressure non-aqueous drilling fluids of Examples 9 and 10 of the present invention exhibit good rheological properties and sedimentation stability even with 8% (by mass / volume) of inferior solid phase contamination. This indicates that the emulsified wetting agent of the present invention effectively improves the surface oil wettability of the high concentration of inferior solid phase, reducing the adverse effects of high concentration of inferior solid phase on the rheological properties and sedimentation stability of the non-aqueous drilling fluid system. In contrast, Comparative Example 4, due to the absence of the self-made emulsified wetting agent, experienced severe sedimentation after standing at high temperature for 72 hours.

[0195] The present invention has been disclosed above with reference to preferred embodiments. However, those skilled in the art should understand that these embodiments are merely illustrative of the invention and should not be construed as limiting its scope. It should be noted that any variations and substitutions equivalent to these embodiments should be considered to be covered within the scope of the claims. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. An emulsified wetting agent, characterized in that, Its structural formula is: R 1 O(CR 2 HCH2O) a CH2CONH(CH2CH2NH) b R 3 , and / or R 1 O(CR 2 HCH2O) a CH2COOR 4 ; Where a is an integer from 1 to 10, and b is an integer from 1 to 4; R 1 It is a saturated or unsaturated, straight or branched, substituted or unsubstituted hydrocarbon group having 6 to 18 carbon atoms; R 2 Selected from one or more of H- and CH3-; R 3 Selected from one or more of H- and -CH2CH2NH2; R 4 It is selected from one or more of CH3-, -CH2CH3, -CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH2CH3, -CH2CH2CH(CH3)2, -CH2CH2OH, and -CH2CH(OH)CH2(OH).

2. The emulsified wetting agent according to claim 1, characterized in that, a is 2-6; b is 1-3; R 1 It is a straight-chain or monounsaturated hydrocarbon group with 16 to 18 carbon atoms; R 2 For H; R 3 For H- or -CH2CH2NH2; R 4 It is one or more of -CH2CH3, -CH(CH3)2, -CH2CH2OH, and -CH2CH(OH)CH2OH.

3. The method for preparing the emulsified wetting agent according to any one of claims 1 to 2, characterized in that, It is prepared by dehydration condensation reaction of fatty alcohol polyoxyalkylene ether carboxylic acid with polyethylene polyamine or alcohol.

4. The preparation method according to claim 3, characterized in that, Includes the following steps: (1) Add 55 to 85 parts by weight of fatty alcohol polyoxyalkylene ether carboxylic acid to the reactor, add 0.001 to 0.003 parts by weight of catalyst, and purge with nitrogen for 0.5 to 1 hour to remove air from the reactor. (2) Heat the reactor to 150℃ to 200℃ at a rotation speed of 200 to 600 rpm; (3) Slowly add 10-45 parts by weight of polyethylene polyamine to the reaction vessel and react for 2-8 hours. Stop the reaction when the acid value is lower than 10 mg KOH / g to obtain the emulsified wetting agent.

5. The preparation method according to claim 3, characterized in that, Includes the following steps: (1) Add 40-85 parts by weight of fatty alcohol polyoxyalkylene ether carboxylic acid to the reactor and purge with nitrogen for 0.5-1 hour to remove air from the reactor. (2) Add 20-60 parts by weight of alcohol and 0.005-0.015 parts by weight of catalyst, and heat the reactor to 70℃-100℃ at a speed of 200-600 rpm, and reflux for 2-8 hours until the acid value is lower than 10 mg KOH / g. (3) Heat the reactor to 105-150°C and recover the alcohol until the amount of recovered alcohol no longer increases, thus obtaining the emulsified wetting agent.

6. The preparation method according to claim 3, characterized in that, The structural formula of the fatty alcohol polyoxyalkylene ether carboxylic acid is: R 1 O(CR 2 HCH2O) a CH2COOH; Where a is an integer from 1 to 10; R 1 It is a saturated or unsaturated, straight or branched, substituted or unsubstituted hydrocarbon group having 6 to 18 carbon atoms; R 2 Selected from one or more of H- and CH3-.

7. The preparation method according to claim 3, characterized in that, The polyethylene polyamine includes one or more of ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine.

8. The preparation method according to claim 3, characterized in that, The alcohols include one or more of methanol, ethanol, propanol, isopropanol, ethylene glycol, glycerol, isoamyl alcohol, and 1-pentanol.

9. A non-water-based drilling fluid, characterized in that, include: The emulsified wetting agent according to any one of claims 1 to 2 or the emulsified wetting agent, base oil, aqueous phase, emulsifier, viscosity modifier, shearing agent, filtration loss reducer, alkalinity modifier and weighting agent prepared by the preparation method according to any one of claims 3 to 8.

10. The non-water-based drilling fluid according to claim 9, characterized in that, Based on a total volume of 100 mL for the base oil and the aqueous phase, the product comprises: 70 to 95 mL of base oil, 5 to 30 mL of aqueous phase, 3 to 6 g of emulsifier, 1 to 5 g of emulsifying wetting agent, 0.25 g to 2 g of viscosity modifier, 1 to 5 g of shearing agent, 2 g to 8 g of filtrate reducer, 2 g to 4 g of alkalinity modifier, and 1089 g to 3733 g of weighting agent.

11. The non-water-based drilling fluid according to claim 9, characterized in that, The base oil includes any one or more of diesel, white oil, and gas-derived oil; the aqueous phase is an inorganic salt solution or an organic salt solution with a solute mass fraction of 20 wt% to 40 wt%.

12. The non-water-based drilling fluid according to claim 9, characterized in that, The emulsifier includes any one or more of fatty acid polyamide emulsifiers; the viscosity modifier is an organic clay.

13. The non-water-based drilling fluid according to claim 9, characterized in that, The cutting agent includes one or more of vegetable oleic acid and vegetable oleic acid dimer acid; the filtration loss reducing agent is selected from any one or more of organic amine-modified humic acid, oxidized asphalt, and sulfonated asphalt with 12 to 18 carbon atoms.

14. The non-water-based drilling fluid according to claim 9, characterized in that, The alkalinity regulator includes any one or both of calcium oxide and calcium hydroxide; the weighting agent includes any one or more of barite, limestone powder, galena powder, and manganese ore powder.

15. The non-water-based drilling fluid according to claim 9, characterized in that, The density of the non-water-based drilling fluid is 1.8 g / cm³. 3 ~2.5g / cm 3 .

16. The method for preparing the non-water-based drilling fluid according to any one of claims 9 to 15, characterized in that, include: (1) Add the emulsifier and the wetting agent to the base oil and stir to mix; (2) Add the viscosity modifier, shearing agent and alkalinity modifier, and stir to mix; (3) Add the aqueous phase and stir to mix; (4) Add the filtration loss reducer and stir to mix; (5) Add the weighting agent and stir to adjust the density of the drilling fluid to the desired value to obtain the non-water-based drilling fluid.

17. The preparation method according to claim 16, characterized in that, In steps (1) to (4), the stirring and mixing time is 5 min to 30 min, and the stirring and mixing speed is 8000 rpm to 12000 rpm.

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