Modified bitumen for drilling fluids and method of making same

Abstract

The application discloses a modified asphalt for drilling fluid and a preparation method thereof. The modified asphalt for drilling fluid comprises the following components in parts by weight: pretreated residue reducing agent, acid anhydride modifier, initiator, stabilizer, modifier and performance regulator. The pretreated residue reducing agent comprises the following components in parts by weight: inferior residue reducing agent: 100 parts; oil sand asphalt: 20-60 parts; and pretreatment agent: 0.1-2 parts. The high softening point asphalt with high softening point and good hydrophilicity is obtained by modifying the difficult-to-handle inferior residue reducing agent and oil sand asphalt, and is suitable for being used as a main material for producing asphalt water-based drilling fluid.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of asphalt, in particular to a modified asphalt for drilling fluid and a preparation method thereof. BACKGROUND

[0002] The asphalt drilling fluid system is mainly based on oil, but the oil-based drilling fluid has certain defects in cost and environmental protection, and the water-based drilling fluid is attracting more and more attention. Although the anhydride modification can improve the softening point and hydrophilic property of asphalt, the asphalt is a relatively inert system, and the reaction capacity with anhydride is poor, and the reaction conversion rate is very low. The unreacted anhydride remains in the asphalt to corrode the equipment, and the small molecule anhydride volatilized after heating is harmful to the human body and the environment, and the low conversion rate also increases the amount of anhydride, and the cost is increased.

[0003] In addition, with the increasing heaviness of crude oil, the yield of vacuum residue is gradually increased, the content of heavy metals and sulfur in the residue is increased, the relative content of saturates and asphaltene in the residue is increased, the relative content of aromatic and resin is reduced, and the association degree of asphaltene is increased, and the form is more complex. The production difficulty of directly preparing high-grade asphalt from poor quality residue is increased. Therefore, for this kind of more and more poor quality residue, if it can be modified to obtain a softening point high, hydrophilic good intermediate for producing drilling fluid asphalt, it will be a better choice.

[0004] CN1415699A discloses a production method of oxidized asphalt, first using a static mixer to mix air and asphalt, so that air is dispersed into asphalt raw materials in the form of small bubbles, and then enters an oxidation device for oxidation reaction. This method can adjust the performance of asphalt when producing ordinary road asphalt and building asphalt, but it is not suitable for producing high softening point asphalt. Because the amount of air existing in asphalt at high temperature is very small, the oxidation efficiency is limited, and the softening point of asphalt cannot be greatly improved, and coking phenomenon exists in the production process.

[0005] CN103805221B discloses a production method of high softening point asphalt, which uses a mixture of coal tar and petroleum asphalt as raw material, and uses the characteristics of coal tar, such as small viscosity and high reactivity at high temperature, to promote the oxidation reaction. However, the oxidation process of coal tar releases a large amount of toxic and harmful gas, which is harmful to the environment and human body, and the prepared high softening point asphalt does not have hydrophilic property, and cannot be used as raw material for preparing asphalt-based water-based drilling fluid.

[0006] In summary, the above methods have problems such as high energy consumption, complex process, environmental pollution, and limited ability to improve the softening point of asphalt in the preparation process. The high softening point asphalt produced has poor hydrophilic property, and is not suitable as raw material for preparing asphalt-based water-based drilling fluid. SUMMARY

[0007] In view of the deficiencies of the prior art, the present application provides a modified asphalt for drilling fluid and a preparation method thereof.The present application uses difficult-to-treat poor residual oil, oil sand asphalt as raw material, and obtains high softening point asphalt with high softening point and good hydrophilicity by modification, which is suitable as main material for producing asphalt water-based drilling fluid.

[0008] The present application provides a modified asphalt for drilling fluid, which comprises the following raw material components by weight fraction: pretreated residual oil: 100 parts; acid anhydride modifier: 2-10 parts, preferably 2-8 parts; initiator: 0.08-0.7 parts, preferably 0.15-0.7 parts; stabilizer: 0.4-1.5 parts, preferably 0.6-1.4 parts; modifier: 0.5-12 parts, preferably 4-10 parts; performance regulator: 0.5-10 parts, preferably 1-8 parts; wherein the pretreated residual oil comprises the following raw material components by weight fraction:

[0009] Poor residual oil: 100 parts;

[0010] Oil sand asphalt: 20-60 parts, preferably 30-50 parts;

[0011] Pretreatment agent: 0.1-2 parts, preferably 0.2-1.2 parts.

[0012] The properties of the poor residual oil include: flash point of 241-256℃, sulfur content of 2.61wt%-3.65wt%, saturated fraction of 26.1%-37.7% by mass fraction, aromatic fraction of 20.2%-34.5% by mass fraction, gum of 18.3%-24.8% by mass fraction, and asphaltene of 21.3%-30.1% by mass fraction, preferably asphaltene of 21.3%-26.0% by mass fraction.

[0013] The poor residual oil also has the following properties: carbon residue value of 21wt%-29wt%, nitrogen content of 0.14wt%-0.61wt%, total content of nickel and vanadium of 320-365μg / g, and condensation index CI of 0.26-0.35.

[0014] The poor residual oil can be Tahe residual oil or other residual oil meeting the above properties, and the poor residual oil is a fraction with initial boiling point greater than 425℃.

[0015] The oil sand asphalt is one or more of Inner Mongolia oil sand asphalt, Qinghai oil sand asphalt, Indonesia oil sand asphalt, and Kazakhstan oil sand asphalt.

[0016] The properties of the oil sand asphalt include: softening point not less than 50℃, preferably 55-65℃, flash point not less than 232℃, preferably 235-256℃, freezing point of 25-32℃, 100℃ viscosity of 1450-1600mm 2 .S -1, preferably 1500-1600 mm 2 .S -1 , the carbon residue is 9.5wt%-15.1wt%, the sulfur content is 2.0wt%-6.1wt%, the carbon content is 84wt%-87wt%, the hydrogen content is 10wt%-12.4wt%, the nitrogen content is 0.2wt%-0.8wt%, the mass fraction of saturates is 10.1%-30.7%, the mass fraction of aromatics is 15.6%-35.9%, the mass fraction of resins is 30.4%-45.8%, and the mass fraction of asphaltenes is 10.7%-27.3%, preferably the mass fraction of asphaltenes is 11.3%-25.2%.

[0017] The pre-treatment agent is polyphosphoric acid with a high phosphoric acid content, wherein the mass content of phosphoric acid contained is 125%-145% as H3PO4, preferably 130%-140%.

[0018] The acid anhydride modifier is one or more of maleic anhydride, polyisobutylene succinic anhydride, methyl nadic anhydride, modified methyl nadic anhydride MNA-10, dodecenyl succinic anhydride, tung oil anhydride, polyazelaic anhydride, polyglutaric anhydride, polyitaconic anhydride, or hydrolyzed polymaleic anhydride.

[0019] The initiator is one or more of dicumyl peroxide, tert-butyl hydroperoxide, benzoyl peroxide, sodium metabisulfite, azobisisobutyronitrile, azobisisoheptyl nitrile, cumene hydroperoxide.

[0020] The stabilizer comprises polyphosphoric acid with a low phosphoric acid content, and at least one of lauryl alcohol polyoxyethylene ether, cetyl alcohol polyoxyethylene ether, stearyl alcohol polyoxyethylene ether, nonyl phenol polyoxyethylene ether, octyl phenol polyoxyethylene ether, dinonyl phenol polyoxyethylene ether, and docosanol.

[0021] The content of the polyphosphoric acid with a low phosphoric acid content is 20%-50% by mass of the stabilizer, preferably 25%-45%.

[0022] The polyphosphoric acid with a low phosphoric acid content has a mass content of phosphoric acid of 105%-115% as H3PO4, preferably 105%-110%.

[0023] The modifier is one or more of melamine, melamine formaldehyde resin, carbamide, and urea formaldehyde resin.

[0024] The performance regulator is waste activated carbon adsorbent which is specially used for adsorbing organic waste gas of a refinery before being discarded. The waste activated carbon adsorbent adsorbs a large amount of organic waste gas (including aliphatic and aromatic hydrocarbons, alcohols, lipids, ketones, etc.), catalyst solid particles, soot, etc. The activated carbon adsorbent preferably is activated carbon containing copper ions and / or iron ions (the total mass of copper ions and / or iron ions accounts for 1% to 10% of the mass of the activated carbon, preferably 2% to 8%). Among them, micropores (<2nm) account for 20% to 40% of the total pore volume, mesopores (2nm to 50nm) account for 10% to 25% of the total pore volume, and macropores (>50nm) account for 35% to 70% of the total pore volume.

[0025] The second aspect of the present application provides a preparation method of modified asphalt for drilling fluid, comprising:

[0026] (1) adding the poor residual oil to be heated to a flow state to a reaction kettle together with oil sand asphalt and a pretreatment agent, stirring and heating to a reaction temperature, and carrying out heat preservation treatment after the reaction is completed; after the heat preservation is completed, carrying out vacuum deep pulling to obtain pretreated residual oil;

[0027] (2) adding an acid anhydride modifier and an initiator to the material obtained in step (1), stirring and heating to a reaction temperature, and carrying out reaction under protective gas;

[0028] (3) adding a stabilizer to the material obtained in step (2), stirring and heating to a reaction temperature, and carrying out reaction under protective gas; after the reaction is completed, adding a modifier and continuing the reaction;

[0029] (4) moving the material obtained in step (3) to an oxidation reaction kettle, adding a performance regulator, and carrying out oxidation reaction by introducing oxidizing gas under stirring to obtain modified asphalt for drilling fluid.

[0030] In step (1), the temperature for heating the poor residual oil to a flow state is 140℃ to 155℃.

[0031] In step (1), the reaction kettle is a high-pressure reaction kettle, and the initial temperature of the reaction kettle is adjusted to 130℃ to 150℃.

[0032] In step (1), the stirring speed is 600 to 800r / min. The heating to the reaction temperature is carried out by using programmed temperature rising to heat to the reaction temperature, the temperature rising rate is 1℃ to 3℃ / min, the reaction temperature is 140℃ to 180℃, preferably 155℃ to 170℃, and the reaction time is 3 to 6h.

[0033] In step (1), the heat preservation treatment is carried out at 120℃ to 135℃ for 10 to 16h.

[0034] In step (1), the end temperature of the vacuum deep-cut is 453-460℃ (converted to normal pressure).

[0035] In step (2), the stirring speed is 600-800 r / min. The heating to the reaction temperature is carried out by programmed heating to the reaction temperature at a heating rate of 1-3℃ / min. The reaction temperature is 160-180℃, and the reaction time is 6-8 h. The protective gas is inert gas and / or N2. The amount of the protective gas is such that the pressure in the reactor is maintained at 0.3-0.9 MPa, preferably 0.5-0.9 MPa.

[0036] In step (3), after the addition of the stabilizer, the stirring speed is 300-600 r / min, and the reaction temperature is 130-145℃, and the reaction time is 3-6 h. After the addition of the modifier, the reaction temperature is 140-170℃, preferably 145-160℃, and the reaction time is 2-4 h.

[0037] In step (3), the protective gas is inert gas and / or N2. The amount of the protective gas is such that the pressure in the reactor is maintained at 0.3-0.9 MPa, preferably 0.4-0.8 MPa.

[0038] In step (4), the performance regulator is subjected to water treatment before use, specifically, the performance regulator is soaked in distilled water for 15-24 h, and then dried for standby.

[0039] In step (4), the oxidizing gas is oxygen-enriched air (oxygen content 30-55 vol.%), and the gas flow rate is 0.06-0.4 m 3 / kg / h; the oxidation temperature is 210-320℃, preferably 220-300℃, and the oxidation time is 4-8 h, and the stirring speed during the oxidation is 50-200 r / min.

[0040] The obtained drilling fluid is subjected to low-temperature freezing and crushing with the modified point pitch to obtain a modified point pitch for drilling fluid.

[0041] The freezing temperature is -15 to -45℃, preferably -20 to -35℃, and the freezing time is 6-24 h, preferably 12-24 h.

[0042] The crushing process is carried out in a high-speed shearing crusher, a colloid mill, a ball mill crusher or the like, and the crushing time is 30-100 s, preferably 30-60 s.

[0043] Compared with the prior art, the present application has the following advantages:

[0044] (1) The inferior residue and oil sand pitch used in the present application are low value-added raw materials, which are not suitable for producing high-grade road pitch, such as Tahe residue with high asphaltene content and Inner Mongolia oil sand pitch with very special form and extremely poor comprehensive performance. The two raw materials have special properties and cooperate with each other, and after pretreatment and deep vacuum extraction, the structure of the two is further optimized, and the high-temperature softening point and hydrophilicity of the raw material are greatly improved. After subsequent modification treatment, it can be used to prepare high-softening-point pitch for drilling fluid, which expands the use of inferior raw materials and improves their added value.

[0045] (2) The pretreated residue with specific composition is modified by acid anhydride, which not only increases the active sites and contact area of acid anhydride and pitch, makes the Diels-Alder reaction between acid anhydride and pitch easier, but also greatly increases the polarity of the asphaltene surface, enhances the π-π charge transfer effect and hydrogen bond force, and effectively increases the conversion rate of acid anhydride reaction.

[0046] (3) The modifier used in the present application can react with the active components in the pitch, thereby improving the hydrophilic performance of the pitch; the stabilizer further improves the hydrophilic performance of the material and the adhesion to the well wall after reaction, and is resistant to high temperature, hard water, inorganic salt, etc., and is suitable for complex downhole environment; the two can also cooperate to capture unreacted small molecule acid anhydride, which not only improves the reaction conversion rate but also avoids environmental pollution caused by acid anhydride volatilization.

[0047] (4) The performance regulator introduced in the present application contains metal-loaded, catalyst particles, and smoke particles, which can be used as catalysts for oxidation reaction, accelerating the oxidation reaction; the adsorbed organic matter makes it more uniformly dispersed in the pitch, and after water treatment, the water adsorbed in the pores of different sizes is quickly gasified, increasing the contact area between oxygen-rich gas and pitch and improving the reaction rate. The addition of activated carbon further improves the high-temperature stability of the pitch. The performance regulator used in the present application belongs to refinery solid waste, which is low in cost and environmentally friendly. DETAILED DESCRIPTION

[0048] The technical solutions of the present application are further described below by examples, but these examples cannot limit the protection scope of the present application, and the % is mass fraction.

[0049] In the present application, the softening point is tested according to the requirements of “Highway Engineering Asphalt and Asphalt Mixture Test Regulations JTG E20-2011”, the contact angle is measured by OCA25 video optical contact angle measuring instrument developed and produced by Germany dataphysics company, and the high-temperature and high-pressure filtration loss is determined according to SY / T5621 method.

[0050] Example 1

[0051] (1) 100 parts of Tahe reduced residue (properties are shown in Table 1) heated to a flowable state and 40 parts of Inner Mongolia oil sand pitch (properties are shown in Table 2) were added to a high-pressure reaction kettle at a temperature of 130°C and stirred, 0.4 parts of polyphosphoric acid with a phosphoric acid content (calculated as H3PO4) of 135% was slowly added to the reaction kettle (added within 3 minutes), and the temperature was programmed to increase to 160°C at a rate of 2°C / min under stirring at a speed of 600 r / min, and the reaction time was 4 hours; after the reaction was completed, the reaction kettle was placed in a heat preservation state, the heat preservation temperature was 120°C, and the heat preservation time was 10 hours. After the heat preservation was completed, vacuum deep-cutting was performed to obtain vacuum residue with a temperature greater than 455°C.

[0052] (2) 4 parts of maleic anhydride and 0.5 parts of dicumyl peroxide were added to the vacuum residue obtained in step (1), the temperature was programmed to increase to 175°C at a rate of 2°C / min under stirring at a speed of 650 r / min, and after the temperature increase was completed, the reaction was performed under a N2 atmosphere, the pressure in the reaction kettle was maintained at 0.6 MPa, and the reaction time was 6 hours.

[0053] (3) 1.0 parts of a stabilizer (a mixture of polyphosphoric acid, lauryl alcohol polyoxyethylene ether, and cetyl alcohol polyoxyethylene ether, wherein the polyphosphoric acid (phosphoric acid content (calculated as H3PO4) is 105%) accounts for 30%, the lauryl alcohol polyoxyethylene ether accounts for 30%, and the cetyl alcohol polyoxyethylene ether accounts for 40% based on the total mass of the stabilizer) was added to the material obtained in step (2), and the reaction was performed at 130°C for 4 hours, after the reaction was completed, the temperature was increased to 150°C and 5 parts of melamine was added, and the reaction was continued for 3 hours; the reactions were all performed under a N2 atmosphere, the pressure in the reaction kettle was maintained at 0.8 MPa, and the stirring speed was 600 r / min.

[0054] (4) The material obtained in step (3) was moved to an oxidation reaction kettle, 6 parts of discarded activated carbon adsorbent (micropores account for 25%, mesopores account for 15%, and macropores account for 60%) soaked in distilled water for 15 hours was added, the activated carbon adsorbent was loaded with copper ions and iron ions and had adsorbed a large amount of organic waste gas, oxygen-enriched air (oxygen content is 45%) was introduced under stirring at a speed of 100 r / min, the gas flow rate was 0.15 m3 / h, the oxidation temperature was 260°C, and the oxidation time was 5 hours to obtain modified pitch for drilling fluid. 3

[0055] (5) 100 g of low-temperature frozen modified pitch for drilling fluid (low-temperature freezing conditions: temperature -30°C, time 12 hours) was added to a high-speed pulverizer, and was pulverized for 30 seconds to obtain modified pitch for drilling fluid particles A1, and the average particle size was 80 μm.

[0056] Example 2

[0057] ​(1) 100 parts of Tahe reduced residue (properties are shown in Table 1) heated to a flowable state and 40 parts of Inner Mongolia oil sand pitch (properties are shown in Table 2) were added to a high-pressure reaction kettle at a temperature of 130°C and stirred, 0.2 parts of polyphosphoric acid with a phosphoric acid content (calculated as H3PO4) of 135% was slowly added to the reaction kettle (added within 3 minutes), and the temperature was programmed to increase to 160°C at a rate of 2°C / min under stirring at a speed of 600 r / min, and the reaction time was 4 hours; after the reaction was completed, the reaction kettle was placed in a heat preservation state, the heat preservation temperature was 130°C, and the heat preservation time was 12 hours. After the heat preservation was completed, vacuum deep-cutting was performed to obtain vacuum residue with a temperature greater than 455°C.

[0058] (2) 4.75 parts of tung oil anhydride and 0.6 parts of dicumyl peroxide were added to the vacuum residue obtained in step (1), the temperature was programmed to increase to 175°C at a rate of 2°C / min under stirring at a speed of 650 r / min, and after the temperature increase was completed, the reaction was performed under a N2 atmosphere, the pressure in the reaction kettle was maintained at 0.6 MPa, and the reaction time was 6 hours.

[0059] (3) 1.0 parts of a stabilizer (a mixture of polyphosphoric acid, lauryl alcohol polyoxyethylene ether, and cetyl alcohol polyoxyethylene ether, wherein the polyphosphoric acid (phosphoric acid content (calculated as H3PO4) is 105%) accounts for 30%, the lauryl alcohol polyoxyethylene ether accounts for 30%, and the cetyl alcohol polyoxyethylene ether accounts for 40% based on the total mass of the stabilizer) was added to the material obtained in step (2), and the reaction was performed at 130°C for 4 hours, after the reaction was completed, the temperature was increased to 150°C, and 3 parts of melamine and 2 parts of melamine formaldehyde resin were added, and the reaction was continued for 3 hours; the reactions were all performed under a N2 atmosphere, the pressure in the reaction kettle was maintained at 0.8 MPa, and the stirring speed was 600 r / min.

[0060] (4) The material obtained in step (3) was moved to an oxidation reaction kettle, 6 parts of discarded activated carbon adsorbent (micropores account for 25%, mesopores account for 15%, and macropores account for 60%) soaked in distilled water for 24 hours was added (the activated carbon adsorbent was loaded with copper ions and iron ions and had adsorbed a large amount of organic waste gas), oxygen-enriched air (oxygen content is 45%) was introduced under stirring at a speed of 100 r / min, the gas flow rate was 0.15 m3 / h, the oxidation temperature was 280°C, and the oxidation time was 4 hours, to obtain modified pitch for drilling fluid. 3

[0061] (5) 100 g of low-temperature frozen modified pitch for drilling fluid (low-temperature freezing conditions: temperature -32°C, time 10 hours) was added to a high-speed pulverizer, and was pulverized for 40 seconds to obtain modified pitch for drilling fluid particles A2, and the average particle size was 85 μm.

[0062] Example 3

[0063] ​(1) 100 parts of Tahe reduced residue (properties are shown in Table 1) heated to a flowable state and 35 parts of Inner Mongolia oil sand pitch (properties are shown in Table 2) were added to a high-pressure reaction kettle at a temperature of 130°C and stirred, 0.4 parts of polyphosphoric acid with a phosphoric acid content (calculated as H3PO4) of 135% was slowly added to the reaction kettle (added within 3 min), and the temperature was programmed to increase to 160°C at a rate of 2°C / min under stirring at a speed of 600 r / min, and the reaction time was 4 h; after the reaction was completed, the reaction kettle was placed in a heat preservation state, the heat preservation temperature was 120°C, and the heat preservation time was 10 h. After the heat preservation was completed, vacuum deep-cutting was performed to obtain vacuum residue with a temperature greater than 455°C.

[0064] (2) 5 parts of maleic anhydride and 0.5 parts of dicumyl peroxide and 0.1 parts of azobisisobutyronitrile were added to the vacuum residue obtained in step (1), the temperature was programmed to increase to 170°C at a rate of 2°C / min under stirring at a speed of 650 r / min, and after the temperature increase was completed, the reaction was performed under a N2 atmosphere, the pressure in the reaction kettle was maintained at 0.6 MPa, and the reaction time was 6 h.

[0065] (3) 1.2 parts of a stabilizer (a mixture of polyphosphoric acid, lauryl alcohol polyoxyethylene ether, and nonylphenol polyoxyethylene ether, wherein the polyphosphoric acid (phosphoric acid content (calculated as H3PO4) is 105%) accounts for 35%, the lauryl alcohol polyoxyethylene ether accounts for 25%, and the nonylphenol polyoxyethylene ether accounts for 40% based on the total mass of the stabilizer) was added to the material obtained in step (2), and the reaction was performed at 130°C for 4 h, after the reaction was completed, the temperature was increased to 150°C, 5 parts of melamine and 1 part of carbamide were added, and the reaction was continued for 3 h; the reactions were all performed under a N2 atmosphere, the pressure in the reaction kettle was maintained at 0.8 MPa, and the stirring speed was 600 r / min.

[0066] (4) The material obtained in step (3) was moved into an oxidation reaction kettle, 8 parts of discarded activated carbon adsorbent (micropores account for 30%, mesopores account for 15%, and macropores account for 55%) soaked in distilled water for 18 h (the activated carbon adsorbent was loaded with copper ions and iron ions and had adsorbed a large amount of organic waste gas) was added, oxygen-enriched air (oxygen content is 50%) was introduced under stirring at a speed of 150 r / min, the gas flow rate was 0.2 m 3 / kg / h, the oxidation temperature was 240°C, and the oxidation time was 6 h to obtain modified pitch for drilling fluid.

[0067] (5) 100 g of low-temperature frozen modified pitch for drilling fluid (low-temperature freezing conditions: temperature -35°C, time 14 h) was added to a high-speed pulverizer, and was pulverized for 30 s to obtain modified pitch for drilling fluid particles A3 with an average particle size of 95 μm.

[0068] Example 4

[0069] (1) 100 parts of Tahe reduced residue (properties are shown in Table 1) heated to a flowable state and 50 parts of Inner Mongolia oil sand pitch (properties are shown in Table 2) were added to a high-pressure reaction kettle at a temperature of 130°C and stirred, 0.6 parts of polyphosphoric acid with a phosphoric acid content (calculated as H3PO4) of 135% was slowly added to the reaction kettle (added within 3 min), and the temperature was programmed to increase to 160°C at a rate of 2°C / min under stirring at a speed of 600 r / min, and the reaction time was 4 h; after the reaction was completed, the reaction kettle was placed in a heat preservation oven, the heat preservation temperature was 120°C, and the heat preservation time was 10 h. After the heat preservation was completed, vacuum deep-cutting was performed to obtain vacuum residue with a temperature greater than 455°C.

[0070] (2) 4.6 parts of maleic anhydride and 0.5 parts of dicumyl peroxide and 0.1 parts of azobisisobutyronitrile were added to the vacuum residue obtained in step (1), the temperature was programmed to increase to 170°C at a rate of 2°C / min under stirring at a speed of 650 r / min, and after the temperature increase was completed, the reaction was performed under a N2 atmosphere, the pressure in the reaction kettle was maintained at 0.6 MPa, and the reaction time was 6 h.

[0071] (3) 1.1 parts of a stabilizer (a mixture of polyphosphoric acid, lauryl alcohol polyoxyethylene ether, and nonylphenol polyoxyethylene ether, wherein the polyphosphoric acid (phosphoric acid content (calculated as H3PO4) is 105%) accounts for 35%, the lauryl alcohol polyoxyethylene ether accounts for 25%, and the nonylphenol polyoxyethylene ether accounts for 40% based on the total mass of the stabilizer) was added to the material obtained in step (2), and the reaction was performed at 130°C for 4 h, after the reaction was completed, the temperature was increased to 150°C, 5 parts of melamine and 1 part of urea-formaldehyde resin were added, and the reaction was continued for 3 h; the reactions were all performed under a N2 atmosphere, the pressure in the reaction kettle was maintained at 0.8 MPa, and the stirring speed was 600 r / min.

[0072] (4) The material obtained in step (3) was moved to an oxidation reaction kettle, 7 parts of discarded activated carbon adsorbent (30% micropores, 15% mesopores, and 55% macropores) soaked in distilled water for 18 h (the activated carbon adsorbent was loaded with copper ions and iron ions and had adsorbed a large amount of organic waste gas) was added, oxygen-enriched air (oxygen content is 50%) was introduced under stirring at a speed of 150 r / min, the gas flow rate was 0.2 m 3 / kg / h, the oxidation temperature was 240°C, and the oxidation time was 6 h to obtain modified pitch for drilling fluid.

[0073] (5) 100 g of low-temperature frozen modified pitch for drilling fluid (low-temperature freezing conditions: temperature -30°C, time 20 h) was added to a high-speed pulverizer, and was pulverized for 30 s to obtain modified pitch for drilling fluid particles A4 with an average particle size of 85 μm.

[0074] Comparative Example 1

[0075] Other than Example 1, only 100 parts of Tahe reduced residue (properties see Table 1) and 40 parts of Inner Mongolia oil sand pitch (properties see Table 2) in step (1) are replaced by 140 parts of Inner Mongolia oil sand pitch (properties see Table 2) and stirred in a high-pressure reaction kettle with a temperature of 130°C. Finally, modified pitch particles B2 are obtained.

[0076] Comparative Example 2

[0077] Other than Example 1, only 100 parts of Tahe reduced residue (properties see Table 1) and 40 parts of Inner Mongolia oil sand pitch (properties see Table 2) in step (1) are replaced by 140 parts of Inner Mongolia oil sand pitch (properties see Table 2) and stirred in a high-pressure reaction kettle with a temperature of 130°C. Finally, modified pitch particles B2 are obtained.

[0078] Comparative Example 3

[0079] Other than Example 1, only 100 parts of Tahe reduced residue (properties see Table 1) and 40 parts of Inner Mongolia oil sand pitch (properties see Table 2) in step (1) are replaced by 140 parts of Inner Mongolia oil sand pitch (properties see Table 2) and stirred in a high-pressure reaction kettle with a temperature of 130°C. Finally, modified pitch particles B2 are obtained.

[0080] Comparative Example 4

[0081] Other than Example 1, only 100 parts of Tahe reduced residue (properties see Table 1) and 40 parts of Inner Mongolia oil sand pitch (properties see Table 2) in step (1) are replaced by 140 parts of Inner Mongolia oil sand pitch (properties see Table 2) and stirred in a high-pressure reaction kettle with a temperature of 130°C. Finally, modified pitch particles B2 are obtained.

[0082] Test Example

[0083] The softening point, hydrophilicity, and high-temperature and high-pressure filtration loss of the pitch materials obtained in the examples and comparative examples are tested. The modified pitch particles obtained in the examples and comparative examples are added to the prepared base slurry, and the amount of the modified pitch particles added is 2% of the weight of the base slurry. The filtration loss after aging (16h) at different temperatures is measured under a test pressure of 3.45MPa, and the specific results are shown in Table 3. The base slurry is prepared as follows: 2.75g of anhydrous sodium carbonate is added to 1000mL of water, 60g of bentonite is then added, and high-speed stirring is performed for 20 minutes. The mixture is then cured at room temperature for 24 hours, and finally, 6% of fresh water base slurry is obtained.

[0084] Table 1 Properties of Tahe reduced residue used in examples and comparative examples

[0085]

[0086]

[0087] Table 2 Properties of oil sand pitch used in examples and comparative examples

[0088]

[0089]

[0090] Table 3 Properties of modified bitumens obtained in examples and comparative examples

[0091]

[0092] The scope of protection of the present application is not limited by the foregoing examples, but is defined by the claims. Those skilled in the art can make appropriate modifications to the embodiments without departing from the technical idea and the technical scope of the present application, and such modified embodiments are also included in the scope of protection of the present application.

Claims

1. A modified bitumen for drilling fluid, characterized in that, By weight, it includes the following raw material components: pretreatment slag reduction: 100 parts; acid anhydride modifier: 2~10 parts; Initiator: 0.08~0.7 parts; Stabilizer: 0.4~1.5 parts; Modifier: 0.5~12 parts; Performance regulator: 0.5~10 parts; The pretreatment slag reduction, by weight, includes the following raw material components: Inferior slag reduction: 100 portions; Oil sand asphalt: 20-60 parts; Pretreatment agent: 0.1~2 parts; The pretreatment agent is a high-phosphoric acid polyphosphoric acid, wherein the phosphoric acid content, calculated as H3PO4, is 125%~145% by mass. The anhydride modifier is one or more of maleic anhydride, polyisobutylene succinic anhydride, methyl nadic anhydride, dodecenyl succinic anhydride, tung oil anhydride or hydrolyzed polymaleic anhydride. The stabilizer comprises a low-phosphoric acid polyphosphate, and also contains at least one selected from lauryl alcohol polyoxyethylene ether, hexadecyl alcohol polyoxyethylene ether, octadecyl alcohol polyoxyethylene ether, nonylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether, and dinonylphenol polyoxyethylene ether; the low-phosphoric acid polyphosphate content is 20% to 50% by weight of the stabilizer; the low-phosphoric acid polyphosphate contains 105% to 115% phosphoric acid by weight (H3PO4). The modifier is melamine or a combination of melamine and melamine-formaldehyde resin, or a combination of melamine and carbamide, or a combination of melamine and urea-formaldehyde resin. The performance modifier is waste activated carbon adsorbent, and the waste activated carbon is activated carbon containing copper ions and / or iron ions.

2. The modified bitumen for drilling fluid according to claim 1, characterized in that, By weight, it includes the following raw material components: pretreatment slag reduction: 100 parts; acid anhydride modifier: 2-8 parts; Initiator: 0.15~0.7 parts; Stabilizer: 0.6~1.4 parts; Modifier: 4~10 parts; Performance modifier: 1~8 parts.

3. The modified bitumen for drilling fluid according to claim 1, characterized in that, The pretreatment slag reduction comprises, by weight, the following raw material components: Inferior slag reduction: 100 portions; Oil sand asphalt: 30-50 parts; Pretreatment agent: 0.2~1.2 parts.

4. The modified bitumen for drilling fluid according to claim 1, characterized in that, The properties of the inferior slag include: a flash point of 241℃~256℃, a sulfur content of 2.61wt%~3.65wt%, and by mass fraction, saturated components of 26.1%~37.7%, aromatic components of 20.2%~34.5%, resinous components of 18.3%~24.8%, and asphaltene components of 21.3%~30.1%; and / or, The inferior slag also has the following properties: residual carbon value of 21wt%~29wt%, nitrogen content of 0.14wt%~0.61wt%, total nickel and vanadium content of 320~365μg / g, and condensation index CI of 0.26~0.

35.

5. The modified bitumen for drilling fluid according to claim 1, characterized in that, The oil sands asphalt is one or more of the following: Inner Mongolia oil sands asphalt, Qinghai oil sands asphalt, Indonesian oil sands asphalt, and Kazakhstani oil sands asphalt.

6. The modified bitumen for drilling fluid according to claim 1 or 5, characterized in that, The properties of the oil sands bitumen include: softening point not less than 50℃, flash point not less than 232℃, pour point of 25℃~32℃, and viscosity of 1450~1600 mmol / L at 100℃. 2 .S -1 The residual carbon content is 9.5wt%~15.1wt%, the sulfur content is 2.0wt%~6.1wt%, the carbon content is 84wt%~87wt%, the hydrogen content is 10wt%~12.4wt%, and the nitrogen content is 0.2wt%~0.8wt%. By mass fraction, the saturated components account for 10.1%~30.7%, the aromatic components account for 15.6%~35.9%, the resins account for 30.4%~45.8%, and the asphaltenes account for 10.7%~27.3%.

7. The modified bitumen for drilling fluid according to claim 6, characterized in that, The properties of the oil sands bitumen include: softening point of 55℃~65℃, flash point of 235℃~256℃, and viscosity of 1500~1600 mmol / L at 100℃. 2 .S -1 .

8. The modified bitumen for drilling fluid according to claim 1, characterized in that, The high-phosphoric acid content polyphosphoric acid contains 130% to 140% phosphoric acid by mass, calculated as H3PO4.

9. The modified bitumen for drilling fluid according to claim 1, characterized in that, The initiator is one or more of dicumyl peroxide, tert-butyl hydroperoxide, benzoyl peroxide, sodium metabisulfite, azobisisobutyronitrile, azobisisoheptanenitrile, and cumyl hydroperoxide.

10. The modified bitumen for drilling fluid according to claim 1, characterized in that, The content of the low-phosphoric acid polyphosphoric acid is 20% to 50% by mass of the stabilizer.

11. The modified bitumen for drilling fluid according to claim 1, characterized in that, The content of the low-phosphoric acid polyphosphoric acid is 25% to 45% based on the mass of the stabilizer.

12. The modified bitumen for drilling fluid according to claim 1, 10, or 11, characterized in that, The polyphosphoric acid with low phosphoric acid content contains 105% to 110% phosphoric acid by mass, calculated as H3PO4.

13. The modified bitumen for drilling fluid according to claim 1, characterized in that, The waste activated carbon adsorbent has micropores <2nm accounting for 20%~40% of the total pore volume, mesopores 2nm~50nm accounting for 10%~25% of the total pore volume, and macropores >50nm accounting for 35%~70% of the total pore volume.

14. A method for preparing modified bitumen for drilling fluid according to any one of claims 1-13, comprising: (1) Add the inferior slag heated to a fluid state, oil sand asphalt, and pretreatment agent into the reactor, stir and heat to the reaction temperature, and keep warm after the reaction is completed; After the insulation is completed, decompression and deep drawing are performed to obtain pre-treated slag-reduced material. (2) Add anhydride modifier and initiator to the material obtained in step (1), stir and heat to the reaction temperature, and carry out the reaction under protective gas; (3) Add stabilizer to the material obtained in step (2), stir and heat to the reaction temperature, and carry out the reaction under protective gas; after the reaction is completed, add modifier and continue the reaction; (4) Transfer the material obtained in step (3) into an oxidation reactor, add a performance regulator, and introduce an oxidizing gas under stirring to carry out an oxidation reaction. After the reaction is completed, modified bitumen for drilling fluid is obtained.

15. The method according to claim 14, characterized in that, In step (1), the stirring speed is 600~800 r / min; the heating to the reaction temperature is performed by programmed heating at a rate of 1℃~3℃ / min, the reaction temperature is 140℃~180℃, and the reaction time is 3~6h; the heat preservation conditions are: heat preservation at 120℃~135℃ for 10~16h.

16. The method according to claim 15, characterized in that, In step (1), the reaction temperature is 155℃~170℃.

17. The method according to claim 14, characterized in that, In step (1), the termination temperature of the decompression deep drawing is 453℃~460℃.

18. The method according to claim 14, characterized in that, In step (2), the stirring speed is 600~800 r / min; the heating to the reaction temperature is performed by programmed heating at a rate of 1℃~3℃ / min; the reaction temperature is 160℃~180℃, and the reaction time is 6~8h; the protective gas is an inert gas and / or N2; the amount of protective gas is such that the pressure inside the reactor is maintained at 0.5~0.9MPa.

19. The method according to claim 18, characterized in that, In step (2), the amount of protective gas is such that the pressure inside the reactor is maintained at 0.5~0.9MPa.

20. The method according to claim 14, characterized in that, In step (3), after adding the stabilizer, the stirring speed is 300~600 r / min, the reaction temperature is 130℃~145℃, and the reaction time is 3~6h; and / or, after adding the modifier, the reaction temperature is 140℃~170℃, and the reaction time is 2~4h.

21. The method according to claim 14, characterized in that, In step (3), the reaction temperature after adding the modifier is 145℃~160℃.

22. The method according to claim 14, characterized in that, In step (3), the protective gas is an inert gas and / or N2; the amount of the protective gas is such that the pressure inside the reactor is maintained at 0.3~0.9MPa.

23. The method according to claim 14, characterized in that, In step (3), the amount of protective gas is such that the pressure inside the reactor is maintained at 0.4~0.8 MPa.

24. The method according to claim 14, characterized in that, In step (4), the performance regulator is first treated with water before use. Specifically, the performance regulator is soaked in distilled water for 15-24 hours and then dried before use.

25. The method according to claim 14, characterized in that, In step (4), the oxidizing gas is oxygen-enriched air with an oxygen volume content of 30%~55% and a gas flow rate of 0.06~0.4 m³ / s. 3 / kg / h; the oxidation reaction temperature is 210℃~320℃, the oxidation reaction time is 4~8h, and the stirring speed during the oxidation process is 50~200r / min.

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