Environment-friendly non-water-based drilling fluid base fluid

Abstract

The present application relates to the technical fields of drilling fluid base fluid preparation, in particular to an environment-friendly non-water-based drilling fluid base fluid, comprising the following raw materials by weight: 70-80 parts of base oil, 4-5 parts of perfluoropolyether phosphate, 9-10 parts of functional additives, 1-1.4 parts of dodecyl trimethyl ammonium bromide, 0.9-1.1 parts of brominated methyl castor oil acid ester, 2-3 parts of polyoxyethylene oleyl amine, 0.7-0.9 parts of triethanolamine oleate; the present application is complementary by adding perfluoropolyether phosphate and polyoxyethylene oleyl amine to form a compound, thereby enhancing the high-temperature emulsion stability; by adding modified T501, the phenolic hydroxyl group of modified T501 provides active hydrogen atoms, interrupts white oil oxidation chain reaction, prolongs the oxidation induction period, improves the service life of the base fluid, by adding bone powder-wax composite sol and oil-soluble lignite resin to form a compound, the resin crosslinking enhances the strength of the plugging film at high temperature, reduces the invasion of filtrate into the formation, and reduces the pollution of the base fluid.

Description

Technical Field

[0001] This invention relates to the field of non-water-based drilling fluid preparation technology, specifically to an environmentally friendly non-water-based drilling fluid. Background Technology

[0002] Non-water-based drilling fluid base fluid is the basic medium that constitutes the continuous phase of non-water-based drilling fluid. It is the main component of drilling fluid and plays a key role in bearing, suspending, and lubricating during the drilling process.

[0003] The inherent drawbacks of non-water-based drilling fluids are closely related to their non-water properties, primarily manifesting in cost, environmental impact, safety, and application compatibility. Currently, the industry is mitigating some of these issues through the development of low-toxicity synthetic bases, optimization of recovery processes, and the development of specialized treatment agents, but these problems have not been completely overcome. Therefore, in application, a comprehensive balance must be struck between drilling objectives, geological conditions, and environmental requirements. Summary of the Invention

[0004] The purpose of this invention is to provide an environmentally friendly non-water-based drilling fluid base. The environmentally friendly non-water-based drilling fluid base of this invention focuses on the protection of natural components in raw material processing and processing technology, and does not use harmful chemical additives, ensuring high product safety and suitability for long-term use.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an environmentally friendly non-water-based drilling fluid base fluid, characterized in that it is composed of the following raw materials in parts by weight: 70-80 parts base oil, 4-5 parts perfluoropolyether phosphate, 9-10 parts functional additives, 1-1.4 parts dodecyltrimethylammonium bromide, 0.9-1.1 parts brominated methyl ricinoleate, 2-3 parts polyoxyethylene oleylamine, and 0.7-0.9 parts triethanolamine oleate;

[0006] The preferred preparation steps for the environmentally friendly non-water-based drilling fluid base are as follows:

[0007] S1. Add the base oil to the reactor and heat it to 65°C. Add perfluoropolyether phosphate and polyoxyethylene oleamine. Turn on the stirring speed to 10000r / min and stir for 15 minutes.

[0008] S2. Add functional additives, maintain the temperature at 60-65℃ and stir at 6000r / min for 25 minutes;

[0009] S3. Add dodecyltrimethylammonium bromide and methyl ricinoleate bromide and stir at 5000 r / min for 15 minutes. Then add triethanolamine oleate and stir for 10 minutes to obtain an environmentally friendly non-water-based drilling fluid base.

[0010] Preferably, the functional additive in step S2 is composed of the following materials: 20-25% bentonite oleol, 30-35% bone meal-wax composite sol, 35-40% oil-soluble lignite resin, and 10-15% modified T501.

[0011] The functional additives were added in the following order: bentonite oleol, bone meal-wax composite sol, oil-soluble lignite resin, and modified T501.

[0012] Preferably, the modified T501 comprises: 6-10% T501, 25-30% nano-silica, 6-10% silane coupling agent, 70-90% toluene, and 0.2-0.4% triethylamine.

[0013] Preferably, the base oil comprises: 75-80% No. 1 white oil and 20-25% No. 2 white oil;

[0014] Both No. 1 white oil and No. 2 white oil are industrial-grade mineral oils, which are colorless, odorless, and non-fluorescent saturated hydrocarbon mixtures obtained through deep refining of petroleum fractions.

[0015] The No. 1 white oil is the existing No. 3 white oil, and the No. 2 white oil is the existing No. 7 white oil.

[0016] Preferably, the bentonite oleol comprises: 40-50% natural calcium-based bentonite, 8-10% cetyltrimethylammonium bromide, and 45-50% No. 1 white oil.

[0017] Preferably, the bone meal-wax composite sol consists of: 2-4% coral bone meal, 90-95% No. 1 white oil, 0.8-1% methyl brominated ricinoleate, and 1-3% modified polyethylene wax.

[0018] Preferably, the modified polyethylene wax component comprises: 97-99% polyethylene wax, 5-15% benzoyl peroxide tert-butyl ester, 0.5-3% dibenzoyl peroxide, 1-3% stearic acid, and 0.05-0.2% hydroquinone;

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. This invention addresses the core challenges of non-water-based drilling fluids in terms of high temperature, corrosion, and lubrication by using perfluoropolyether phosphate esters through molecular design that combines the chemical inertness of fluorocarbon chains with the surface activity of phosphate esters. Its value lies not only in the improvement of individual performance characteristics but also in the comprehensive optimization of the rheological stability and environmental adaptability of the drilling fluid through mechanisms such as nanomicelle construction and interfacial directional adsorption.

[0021] 2. This invention, by adding modified T501, becomes an "antioxidant barrier" for non-water-based drilling fluids through a dual mechanism of free radical capture and acid product inhibition. Its value is not only reflected in extending the life of the base fluid, but also in comprehensively improving the stability of the system under high temperature and sulfur-containing conditions by protecting the functional structure of emulsifiers, corrosion inhibitors and rheology modifiers.

[0022] 3. This invention significantly reduces the HTHP filtration loss of non-water-based drilling fluids through the dual mechanisms of micron-level physical filling and temperature-sensitive melting sealing by adding bone meal-wax composite sol, thereby improving the safety of operations in fractured reservoirs. When combined with oil-soluble lignite resin, the resin cross-links at high temperatures, enhancing the strength of the sealing membrane and reducing the intrusion of filtrate into the formation. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] It should be noted that all raw materials used in the following experiments are commercially available.

[0025] Example 1: The environmentally friendly non-water-based drilling fluid base fluid is prepared by weighing the following raw materials as needed: 70 parts base oil, 4 parts perfluoropolyether phosphate, 9 parts functional additives, 1 part dodecyltrimethylammonium bromide, 0.9 parts methyl ricinoleate bromide, 2 parts polyoxyethylene oleamine, and 0.7 parts triethanolamine oleate.

[0026] The preparation steps for environmentally friendly non-water-based drilling fluid base fluid are as follows:

[0027] S1. Add the base oil to the reactor and heat it to 65°C. Add perfluoropolyether phosphate and polyoxyethylene oleamine. Turn on the stirring speed to 10000r / min and stir for 15 minutes.

[0028] S2. Add functional additives, maintain the temperature at 60-65℃ and stir at 6000r / min for 25 minutes;

[0029] S3. Add dodecyltrimethylammonium bromide and methyl ricinoleate bromide and stir at 5000 r / min for 15 minutes. Then add triethanolamine oleate and stir for 10 minutes to obtain an environmentally friendly non-water-based drilling fluid base.

[0030] The functional additives are composed of the following materials: 20-25% bentonite oleol, 30-35% bone meal-wax composite sol, 35-40% oil-soluble lignite resin, and 10-15% modified T501.

[0031] The functional additives were added in the following order: bentonite oleol, bone meal-wax composite sol, oil-soluble lignite resin, and modified T501.

[0032] The modified T501 consists of: 6-10% T501, 25-30% nano silica, 6-10% silane coupling agent, 70-90% toluene, and 0.2-0.4% triethylamine.

[0033] The preparation steps of modified T501 are as follows: silane coupling agent and toluene are added to a reaction vessel and mixed. Triethylamine is added and heated to 65°C, then refluxed for 2 hours to obtain an activated intermediate. Nano-silica and a 30% ethanol aqueous solution are added to an ultrasonic disperser for dispersion. T501 and the activated intermediate are added and heated to 60°C, then allowed to stand for 4 hours. The solvent is removed by filtration. The filtrate is added to a vacuum dryer, heated to 60°C under vacuum, and allowed to stand for 4-6 hours to obtain modified T501.

[0034] The base oil composition is: 75-80% No. 1 white oil and 20-25% No. 2 white oil;

[0035] The preparation steps of the base oil are as follows: add No. 1 white oil and No. 2 white oil into a reaction vessel, heat and stir at 80°C and 500 r / min for 10 minutes to obtain the base oil.

[0036] The components of bentonite oleol are: 40-50% natural calcium-based bentonite, 8-10% cetyltrimethylammonium bromide, and 45-50% No. 1 white oil.

[0037] The preparation method of bentonite oleol is as follows: Natural calcium-based bentonite is ground to 200 mesh using a grinder. The calcium-based bentonite particles are placed in a vacuum drying oven and dried at 105℃ for 4 hours to obtain activated bentonite. The activated bentonite, hexadecyltrimethylammonium bromide, and 50% of the total amount of No. 1 white oil are added to a reaction vessel and heated to 65℃. The mixture is dispersed using a 40kHz ultrasonic processor for 30 minutes at a power of 600W to obtain a modified colloid. The modified colloid is centrifuged using a high-speed centrifuge with a separation factor of 3000g for 10 minutes. The upper layer solution is filtered off, and the lower layer precipitate is retained. The lower layer precipitate is washed 2-3 times with anhydrous ethanol and then vacuum filtered using a vacuum filtration device to obtain a modified filter cake. The modified filter cake and the remaining No. 1 white oil are added to a kneader and heated and mixed at 60℃ for 20 minutes. The mixture is then ground and circulated 3 times using a three-roll mill to obtain bentonite oleol.

[0038] The bone meal-wax composite sol consists of: 2-4% coral bone meal, 90-95% No. 1 white oil, 0.8-1% methyl brominated ricinoleate, and 1-3% modified polyethylene wax.

[0039] The preparation steps of the bone meal-wax composite sol are as follows: Coral bone meal is ground to 800 mesh in a planetary ball mill, soaked in 10% hydrogen peroxide (pH 8.5) for 2 hours, dispersed in distilled water in an ultrasonic disperser for 10 minutes, and then dried in a dryer at 60℃ to obtain dried coral bone meal granules. The dried coral bone meal granules, methyl brominated ricinoleate, and 10% of the total amount of white oil (No. 1) are added to a high-speed shear emulsifier and heated to 60℃, stirred at medium speed for 15 minutes to obtain mixed coral bone meal. The mixed coral bone meal is placed in a constant-temperature sealed container at 25℃ and allowed to stand for 24 hours to obtain modified coral bone meal. The modified bone meal and the remaining white oil (No. 1) are added to a high-pressure homogenizer for homogenization, with pressure ranging from 50 MPa to 100 MPa to 150 MPa. At MPa, the air pressure was stabilized for 2 minutes at each stage to obtain a nano bone powder suspension. Modified polyethylene wax was heated to 70°C using a twin-screw extruder, and the nano bone powder suspension was added and stirred for 5 minutes at a speed of 200 r / min to obtain a bone powder-wax composite sol.

[0040] The modified polyethylene wax composition is: 97-99% polyethylene wax, 5-15% benzoyl peroxide tert-butyl ester, 0.5-3% dibenzoyl peroxide, 1-3% stearic acid, and 0.05-0.2% hydroquinone.

[0041] The preparation steps of modified polyethylene wax are as follows: polyethylene wax and benzoyl tert-butyl peroxide are ground into particles using a pulverizer, polyethylene wax particles are dried in a vacuum drying oven, and benzoyl tert-butyl peroxide is dried in a drying oven.

[0042] Polyethylene wax particles, benzoyl tert-butyl peroxide, stearic acid and hydroquinone were added to a ball mill and mixed for 10 minutes to obtain a mixed powder.

[0043] Add the mixed powder to the plow-type mixer, seal and introduce nitrogen gas, heat and start stirring;

[0044] The temperature was cooled to 20-28℃, and the powder was added to a Soxhlet extractor through an 80-mesh sieve. Ethyl acetate was added and the product was refluxed and washed. The washed product was then placed in a vacuum drying oven and heated to obtain modified polyethylene wax.

[0045] Example 2: The environmentally friendly non-water-based drilling fluid base fluid is prepared by weighing the following raw materials as needed: 75 parts base oil, 4.5 parts perfluoropolyether phosphate, 9.5 parts functional additives, 1.2 parts dodecyltrimethylammonium bromide, 1 part methyl ricinoleate bromide, 2.5 parts polyoxyethylene oleamine, and 0.8 parts triethanolamine oleate.

[0046] The preparation steps for environmentally friendly non-water-based drilling fluid base fluid are as follows:

[0047] S1. Add the base oil to the reactor and heat it to 65°C. Add perfluoropolyether phosphate and polyoxyethylene oleamine. Turn on the stirring speed to 10000r / min and stir for 15 minutes.

[0048] S2. Add functional additives, maintain the temperature at 60-65℃ and stir at 6000r / min for 25 minutes;

[0049] S3. Add dodecyltrimethylammonium bromide and methyl ricinoleate bromide and stir at 5000 r / min for 15 minutes. Then add triethanolamine oleate and stir for 10 minutes to obtain an environmentally friendly non-water-based drilling fluid base.

[0050] The functional additive in step S2 consists of the following materials: 20-25% bentonite oleol, 30-35% bone meal-wax composite sol, 35-40% oil-soluble lignite resin, and 10-15% modified T501.

[0051] The functional additives were added in the following order: bentonite oleol, bone meal-wax composite sol, oil-soluble lignite resin, and modified T501.

[0052] The modified T501 consists of: 6-10% T501, 25-30% nano silica, 6-10% silane coupling agent, 70-90% toluene, and 0.2-0.4% triethylamine.

[0053] The preparation steps of modified T501 are as follows: silane coupling agent and toluene are added to a reaction vessel and mixed. Triethylamine is added and heated to 65°C, then refluxed for 2 hours to obtain an activated intermediate. Nano-silica and a 30% ethanol aqueous solution are added to an ultrasonic disperser for dispersion. T501 and the activated intermediate are added and heated to 60°C, then allowed to stand for 4 hours. The solvent is removed by filtration. The filtrate is added to a vacuum dryer, heated to 60°C under vacuum, and allowed to stand for 4-6 hours to obtain modified T501.

[0054] The base oil composition in step S1 is: 75-80% No. 1 white oil and 20-25% No. 2 white oil;

[0055] The preparation steps of the base oil are as follows: add No. 1 white oil and No. 2 white oil into the reaction vessel, heat and stir at 80℃ and 500r / min for 10 minutes to obtain the base oil.

[0056] The components of bentonite oleol are: 40-50% natural calcium-based bentonite, 8-10% cetyltrimethylammonium bromide, and 45-50% No. 1 white oil.

[0057] The preparation method of bentonite oleol is as follows: Natural calcium-based bentonite is ground to 200 mesh using a grinder. The calcium-based bentonite particles are placed in a vacuum drying oven and dried at 105℃ for 4 hours to obtain activated bentonite. The activated bentonite, hexadecyltrimethylammonium bromide, and 50% of the total amount of No. 1 white oil are added to a reaction vessel and heated to 65℃. The mixture is dispersed using a 40kHz ultrasonic processor for 30 minutes at a power of 600W to obtain a modified colloid. The modified colloid is centrifuged using a high-speed centrifuge with a separation factor of 3000g for 10 minutes. The upper layer solution is filtered off, and the lower layer precipitate is retained. The lower layer precipitate is washed 2-3 times with anhydrous ethanol and then vacuum filtered using a vacuum filtration device to obtain a modified filter cake. The modified filter cake and the remaining No. 1 white oil are added to a kneader and heated and mixed at 60℃ for 20 minutes. The mixture is then ground and circulated 3 times using a three-roll mill to obtain bentonite oleol.

[0058] The bone meal-wax composite sol consists of: 2-4% coral bone meal, 90-95% No. 1 white oil, 0.8-1% methyl brominated ricinoleate, and 1-3% modified polyethylene wax.

[0059] The preparation steps of the bone meal-wax composite sol are as follows: Coral bone meal is ground to 800 mesh in a planetary ball mill, soaked in 10% hydrogen peroxide (pH 8.5) for 2 hours, dispersed in distilled water in an ultrasonic disperser for 10 minutes, and then dried in a dryer at 60℃ to obtain dried coral bone meal granules. The dried coral bone meal granules, methyl brominated ricinoleate, and 10% of the total amount of white oil (No. 1) are added to a high-speed shear emulsifier and heated to 60℃, stirred at medium speed for 15 minutes to obtain mixed coral bone meal. The mixed coral bone meal is placed in a constant temperature sealed container at 25℃ and allowed to stand for 24 hours to obtain modified coral bone meal. The modified bone meal and the remaining white oil (No. 1) are added to a high-pressure homogenizer for homogenization, with pressure ranging from 50 MPa to 100 MPa to 150 MPa. At MPa, the air pressure was stabilized for 2 minutes at each stage to obtain a nano bone powder suspension. Modified polyethylene wax was heated to 70°C using a twin-screw extruder, and the nano bone powder suspension was added and stirred for 5 minutes at a speed of 200 r / min to obtain a bone powder-wax composite sol.

[0060] The modified polyethylene wax composition is: 97-99% polyethylene wax, 5-15% benzoyl peroxide tert-butyl ester, 0.5-3% dibenzoyl peroxide, 1-3% stearic acid, and 0.05-0.2% hydroquinone.

[0061] The preparation steps of modified polyethylene wax are as follows: polyethylene wax and benzoyl tert-butyl peroxide are ground into particles using a pulverizer, polyethylene wax particles are dried in a vacuum drying oven, and benzoyl tert-butyl peroxide is dried in a drying oven.

[0062] Polyethylene wax particles, benzoyl tert-butyl peroxide, stearic acid and hydroquinone were added to a ball mill and mixed for 10 minutes to obtain a mixed powder.

[0063] Add the mixed powder to the plow-type mixer, seal and introduce nitrogen gas, heat and start stirring;

[0064] The temperature was cooled to 20-28℃, and the powder was added to a Soxhlet extractor through an 80-mesh sieve. Ethyl acetate was added and the product was refluxed and washed. The washed product was then placed in a vacuum drying oven and heated to obtain modified polyethylene wax.

[0065] Example 3: The environmentally friendly non-water-based drilling fluid base fluid is prepared by weighing the following raw materials as needed: 80 parts base oil, 5 parts perfluoropolyether phosphate, 10 parts functional additives, 1.4 parts dodecyltrimethylammonium bromide, 1.1 parts brominated methyl ricinoleate, 3 parts polyoxyethylene oleamine, and 0.9 parts triethanolamine oleate.

[0066] The preparation steps for environmentally friendly non-water-based drilling fluid base fluid are as follows:

[0067] S1. Add the base oil to the reactor and heat it to 65°C. Add perfluoropolyether phosphate and polyoxyethylene oleamine. Turn on the stirring speed to 10000r / min and stir for 15 minutes.

[0068] S2. Add functional additives, maintain the temperature at 60-65℃ and stir at 6000r / min for 25 minutes;

[0069] S3. Add dodecyltrimethylammonium bromide and methyl ricinoleate bromide and stir at 5000 r / min for 15 minutes. Then add triethanolamine oleate and stir for 10 minutes to obtain an environmentally friendly non-water-based drilling fluid base.

[0070] The functional additives are composed of the following materials: 20-25% bentonite oleol, 30-35% bone meal-wax composite sol, 35-40% oil-soluble lignite resin, and 10-15% modified T501.

[0071] The functional additives were added in the following order: bentonite oleol, bone meal-wax composite sol, oil-soluble lignite resin, and modified T501.

[0072] The modified T501 consists of: 6-10% T501, 25-30% nano silica, 6-10% silane coupling agent, 70-90% toluene, and 0.2-0.4% triethylamine.

[0073] The preparation steps of modified T501 are as follows: silane coupling agent and toluene are added to a reaction vessel and mixed. Triethylamine is added and heated to 65°C, then refluxed for 2 hours to obtain an activated intermediate. Nano-silica and a 30% ethanol aqueous solution are added to an ultrasonic disperser for dispersion. T501 and the activated intermediate are added and heated to 60°C, then allowed to stand for 4 hours. The solvent is removed by filtration. The filtrate is added to a vacuum dryer, heated to 60°C under vacuum, and allowed to stand for 4-6 hours to obtain modified T501.

[0074] The base oil composition in step S1 is: 75-80% No. 1 white oil and 20-25% No. 2 white oil;

[0075] The preparation steps of the base oil are as follows: add No. 1 white oil and No. 2 white oil into the reaction vessel, heat and stir at 80℃ and 500r / min for 10 minutes to obtain the base oil.

[0076] The components of bentonite oleol are: 40-50% natural calcium-based bentonite, 8-10% cetyltrimethylammonium bromide, and 45-50% No. 1 white oil.

[0077] The preparation method of bentonite oleol is as follows: Natural calcium-based bentonite is ground to 200 mesh using a grinder. The calcium-based bentonite particles are placed in a vacuum drying oven and dried at 105℃ for 4 hours to obtain activated bentonite. The activated bentonite, hexadecyltrimethylammonium bromide, and 50% of the total amount of No. 1 white oil are added to a reaction vessel and heated to 65℃. The mixture is dispersed using a 40kHz ultrasonic processor for 30 minutes at a power of 600W to obtain a modified colloid. The modified colloid is centrifuged using a high-speed centrifuge with a separation factor of 3000g for 10 minutes. The upper layer solution is filtered off, and the lower layer precipitate is retained. The lower layer precipitate is washed 2-3 times with anhydrous ethanol and then vacuum filtered using a vacuum filtration device to obtain a modified filter cake. The modified filter cake and the remaining No. 1 white oil are added to a kneader and heated and mixed at 60℃ for 20 minutes. The mixture is then ground and circulated 3 times using a three-roll mill to obtain bentonite oleol.

[0078] The bone meal-wax composite sol consists of: 2-4% coral bone meal, 90-95% No. 1 white oil, 0.8-1% methyl brominated ricinoleate, and 1-3% modified polyethylene wax.

[0079] The preparation steps of the bone powder-wax composite sol are as follows: Coral bone powder is ground to 800 mesh in a planetary ball mill, soaked in 10% hydrogen peroxide at pH 8.5 for 2 hours, dispersed in distilled water in an ultrasonic disperser for 10 minutes, and the dispersed particles are dried in a dryer at 60°C to obtain dried coral bone powder particles. The dried coral bone powder particles, methyl brominated ricinoleate, and 10% of the total amount of No. 1 white oil are added to a high-speed shear emulsifier and heated to 60°C, stirred at medium speed for 15 minutes to obtain mixed coral bone powder. The mixed coral bone powder is placed in a constant temperature sealed container at 25°C and left to stand for 24 hours to obtain modified coral bone powder. The modified bone powder and the remaining No. 1 white oil are added to a high-pressure homogenizer for homogenization, with pressure ranging from 50 MPa to 100 MPa to 150 MPa. At MPa, the air pressure was stabilized for 2 minutes at each stage to obtain a nano bone powder suspension. Modified polyethylene wax was heated to 70°C using a twin-screw extruder, and the nano bone powder suspension was added and stirred for 5 minutes at a speed of 200 r / min to obtain a bone powder-wax composite sol.

[0080] The modified polyethylene wax composition is: 97-99% polyethylene wax, 5-15% benzoyl peroxide tert-butyl ester, 0.5-3% dibenzoyl peroxide, 1-3% stearic acid, and 0.05-0.2% hydroquinone.

[0081] The preparation steps of modified polyethylene wax are as follows: polyethylene wax and benzoyl tert-butyl peroxide are ground into particles using a pulverizer, polyethylene wax particles are dried in a vacuum drying oven, and benzoyl tert-butyl peroxide is dried in a drying oven.

[0082] Polyethylene wax particles, benzoyl tert-butyl peroxide, stearic acid and hydroquinone were added to a ball mill and mixed for 10 minutes to obtain a mixed powder.

[0083] Add the mixed powder to the plow-type mixer, seal and introduce nitrogen gas, heat and start stirring;

[0084] The temperature was cooled to 20-28℃, and the powder was added to a Soxhlet extractor through an 80-mesh sieve. Ethyl acetate was added and the product was refluxed and washed. The washed product was then placed in a vacuum drying oven and heated to obtain modified polyethylene wax.

[0085] Comparative Example 1: The difference from Example 1 is that no perfluoropolyether phosphate was added to the raw materials in this comparative example.

[0086] The difference between Comparative Example 2 and Example 2 is that no modified T501 was added to the raw materials in this comparative example.

[0087] Comparative Example 3 differs from Example 1 in that bone meal-wax composite sol was not added to the raw materials in this comparative example.

[0088] Performance testing: The data results of the environmentally friendly non-water-based drilling fluid base fluids prepared in Examples 1, 2, 3, 1, 2, and 3 are shown in Table 1.

[0089] Table 1 - Test Data Tables for Examples 1-3 and Comparative Examples 1-3

[0090]

[0091] Based on the above data, the following conclusions can be drawn:

[0092] (1) The demulsification voltage values ​​of Examples 1-3 are far superior to those of Comparative Examples 1-3. The key point is that the examples use perfluoropolyether phosphate, which achieves super electrical stability under high temperature and high salt calcium environment through molecular structure design.

[0093] (2) The dynamic shear force of Examples 1-3 is far superior to that of Comparative Examples 1-3. The key point is that the examples add modified T501, which is the key regulating component of dynamic shear force. It achieves a breakthrough effect of high temperature long-term viscosity enhancement and shear resistance strengthening through molecular structure.

[0094] (3) The demulsification voltage values ​​of Examples 1-3 are far superior to those of Comparative Examples 1-3. The key point is that the examples use bone meal-wax composite sol, which is compounded with oil-soluble lignite resin. The resin crosslinks at high temperature to enhance the strength of the sealing membrane and reduce the intrusion of filtrate into the formation.

[0095] Through the above demonstrations, the present invention is significantly superior to the control group in terms of demulsification voltage, high-temperature rheological stability YP loss, and sealing membrane permeability, thus verifying the advanced nature and rationality of the preparation method.

[0096] In the description of this specification, references to terms such as "an embodiment," "example," and "specific example" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0097] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. An environmentally friendly non-water-based drilling fluid base, characterized in that, It is composed of the following raw materials in parts by weight: 70-80 parts base oil, 4-5 parts perfluoropolyether phosphate, 9-10 parts functional additives, 1-1.4 parts dodecyltrimethylammonium bromide, 0.9-1.1 parts brominated methyl ricinoleate, 2-3 parts polyoxyethylene oleamine, and 0.7-0.9 parts triethanolamine oleate; The preparation steps for environmentally friendly non-water-based drilling fluid base fluid are as follows: S1. Add the base oil to the reactor and heat it to 65°C. Add perfluoropolyether phosphate and polyoxyethylene oleamine. Turn on the stirring speed to 10000r / min and stir for 15 minutes. S2. Add functional additives, maintain the temperature at 60-65℃ and stir at 6000r / min for 25 minutes; S3. Add dodecyltrimethylammonium bromide and methyl ricinoleate bromide and stir at 5000 r / min for 15 minutes. Add triethanolamine oleate and stir for 10 minutes to obtain an environmentally friendly non-water-based drilling fluid base. The functional additive in step S2 consists of the following materials: 20-25% bentonite oleol, 30-35% bone meal-wax composite sol, 35-40% oil-soluble lignite resin, and 10-15% modified T501. The functional additives are added in the following order: bentonite oleol, bone meal-wax composite sol, oil-soluble lignite resin, and modified T501. The modified T501 comprises: 6-10% T501, 25-30% nano-silica, 6-10% silane coupling agent, 70-90% toluene, and 0.2-0.4% triethylamine; The preparation steps of the modified T501 are as follows: silane coupling agent and toluene are added to a reaction vessel and mixed; triethylamine is added and heated to 65°C, then refluxed for 2 hours to obtain an activation intermediate; nano-silica and a 30% ethanol aqueous solution are added to an ultrasonic disperser for dispersion; T501 and the activation intermediate are added and heated to 60°C, then allowed to stand for 4 hours; the solvent is removed by filtration; the filtrate is added to a vacuum dryer and heated to 60°C under vacuum, then allowed to stand for 4-6 hours to obtain the modified T501; The bone meal-wax composite sol consists of: 2-4% coral bone meal, 90-95% No. 1 white oil, 0.8-1% methyl brominated ricinoleate, and 1-3% modified polyethylene wax. The preparation steps of the bone powder-wax composite sol are as follows: Coral bone powder is ground in a planetary ball mill, soaked in 10% hydrogen peroxide at pH 8.5, dispersed in an ultrasonic disperser with distilled water, and the dispersed particles are dried in a dryer to obtain dried coral bone powder particles. The dried coral bone powder particles, methyl brominated ricinoleate, and 10% of the total amount of No. 1 white oil are added to a high-speed shear emulsifier and heated and stirred at high speed to obtain mixed coral bone powder. The mixed coral bone powder is placed in a constant temperature sealed container and left to stand at 25°C for 24 hours to obtain modified coral bone powder. The modified bone powder and the remaining No. 1 white oil are added to a high-pressure homogenizer for homogenization to obtain a nano bone powder suspension. Modified polyethylene wax is heated using a twin-screw extruder, added to the nano bone powder suspension and stirred to obtain the bone powder-wax composite sol.

2. The environmentally friendly non-water-based drilling fluid according to claim 1, characterized in that, The base oil in step S1 consists of 75-80% No. 1 white oil and 20-25% No. 2 white oil. The preparation steps of the base oil are as follows: add No. 1 white oil and No. 2 white oil into a reaction vessel, heat and stir at 80°C and 500 r / min for 10 minutes to obtain the base oil.

3. The environmentally friendly non-water-based drilling fluid according to claim 2, characterized in that, The bentonite oleol consists of: 40-50% natural calcium-based bentonite, 8-10% cetyltrimethylammonium bromide, and 45-50% No. 1 white oil.

4. The environmentally friendly non-water-based drilling fluid according to claim 3, characterized in that, The preparation method of the bentonite oleol is as follows: natural calcium-based bentonite is ground using a grinder, and the calcium-based bentonite particles are placed in a vacuum drying oven for vacuum drying to obtain activated bentonite. The activated bentonite, hexadecyltrimethylammonium bromide, and 50% of the total amount of No. 1 white oil are added to a reaction vessel and heated. The mixture is dispersed using a 40kHz ultrasonic processor to obtain a modified colloid. The modified colloid is centrifuged using a high-speed centrifuge, the upper layer solution is filtered off, and the lower layer precipitate is retained. The lower layer precipitate is washed 2-3 times with anhydrous ethanol and vacuum filtered using a vacuum filtration device to obtain a modified filter cake. The modified filter cake and the remaining No. 1 white oil are added to a kneader and heated and mixed. The mixture is then ground and circulated 3 times using a three-roll mill to obtain the bentonite oleol.

5. The environmentally friendly non-water-based drilling fluid according to claim 1, characterized in that, The modified polyethylene wax composition is: 97-99% polyethylene wax, 5-15% benzoyl peroxide tert-butyl ester, 0.5-3% dibenzoyl peroxide, 1-3% stearic acid, and 0.05-0.2% hydroquinone.

6. The environmentally friendly non-water-based drilling fluid according to claim 5, characterized in that, The preparation steps of the modified polyethylene wax are as follows: the polyethylene wax and benzoyl tert-butyl peroxide are ground into particles by a pulverizer, the polyethylene wax particles are placed in a vacuum drying oven for drying, and the benzoyl tert-butyl peroxide is placed in a drying oven for drying. Polyethylene wax particles, benzoyl tert-butyl peroxide, stearic acid and hydroquinone were added to a ball mill and mixed for 10 minutes to obtain a mixed powder. Add the mixed powder to the plow-type mixer, seal and introduce nitrogen gas, heat and start stirring; The temperature was cooled to 20-28℃, and the powder was added to a Soxhlet extractor through an 80-mesh sieve. Ethyl acetate was added and the product was refluxed and washed. The washed product was then placed in a vacuum drying oven and heated to obtain modified polyethylene wax.

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