A low-cost integrated emulsifier for high-temperature oil-based drilling fluid and its preparation method

Abstract

The present invention belongs to the technical field of oil and gas field chemistry, and specifically discloses a low-cost high-temperature oil-based drilling fluid integrated emulsifier and a preparation method thereof. The high-temperature oil-based drilling fluid integrated emulsifier of the present invention is made of the following components in mass percentage: 94.7%-95.4% of vegetable asphalt, 4.3%-5.0% of diethylenetriamine, and 0.3% of 98wt% concentrated sulfuric acid. The vegetable asphalt undergoes an esterification reaction under the action of concentrated sulfuric acid, and then diethylenetriamine is added. The temperature is raised to undergo comprehensive reactions such as amidation, amide exchange, and esterification, and finally a high-temperature emulsifier for oil-based drilling fluid integrating the functions of the main emulsifier and the auxiliary emulsifier is obtained. The main emulsifier component is mainly the high-grade mixed ester therein, and the auxiliary emulsifier component is mainly polyamide. This product has good stability, a relatively high demulsification voltage, and can withstand a temperature of up to 220°C.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas field chemistry, and particularly relates to a low-cost high-temperature oil-based drilling fluid integrated emulsifier and a preparation method thereof. Background Art

[0002] Drilling is a key link in oil exploitation, and drilling fluid is as important to drilling as blood is to the human body. As the depth of oil well exploitation continues to increase, the formation temperature and pressure are also getting higher and higher. Water-based drilling fluid has poor temperature resistance and inhibition performance, so oil-based drilling fluid must be used in the latter half of drilling. Oil-based drilling fluid is in the form of emulsion, and the key to the temperature resistance performance of oil-based drilling fluid lies in the stability of the emulsion in high-temperature environment, and the emulsifier is the key factor determining the stability of the emulsion. The current oil-based drilling fluid emulsifiers resistant to 220 °C high temperature mainly use high fatty acids, polyethylenepolyamines, polyols, polyacids, polyacid anhydrides, etc. as raw materials. Although the application effect is good, the prices of these raw materials are basically relatively high, resulting in a relatively high overall price of high-temperature oil-based drilling fluid emulsifiers in the industry. Finding low-cost raw materials to reduce the cost of high-temperature oil-based drilling fluid emulsifiers has become an important topic in the industry. Summary of the Invention

[0003] Aiming at the deficiencies existing in the above-mentioned prior art, the purpose of the present invention is to provide a low-cost high-temperature oil-based drilling fluid integrated emulsifier and a preparation method thereof. The high-temperature oil-based drilling fluid integrated emulsifier prepared by the present invention using plant asphalt as the main raw material can achieve good use effect in a high-temperature environment of 220 °C and has low cost.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0005] A low-cost high-temperature oil-based drilling fluid integrated emulsifier is made from the following raw materials by mass percentage: 94.7%-95.4% of plant asphalt, 4.3%-5.0% of diethylenetriamine, and 0.3% of 98wt% concentrated sulfuric acid.

[0006] Its preparation method includes the following steps:

[0007] Step 1: Weigh the raw materials according to the ratio, add plant asphalt into the reaction kettle, turn on heating and stirring, and dropwise add 98wt% concentrated sulfuric acid. After dropping, react at a temperature of 138 °C - 140 °C for 2.0 - 3.0 h;

[0008] Step 2: Start heating up. Add diethylenetriamine into the reaction kettle. First, let it react within the temperature range of 172°C - 176°C for 2.0 - 3.0 h. After the reaction is completed, continue heating up and start vacuum dehydration while adding diethylenetriamine. Then, let it react within the temperature range of 186°C - 190°C for 0.5 - 1.0 h until no more water comes out from the reaction kettle. Cool it down to room temperature to obtain the high-temperature oil-based drilling fluid integrated emulsifier.

[0009] Preferably, in Step 1, react at a temperature of 138°C - 140°C for 2.5 h; in Step 2, first react within the temperature range of 172°C - 176°C for 2.5 h, and then react within the temperature range of 186°C - 190°C for 1.0 h.

[0010] Further, in Step 1, start heating to 138°C, set the stirring speed to 140 - 200 r / min, preferably 160 r / min, and then dropwise add 98 wt% concentrated sulfuric acid.

[0011] Further, in Step 2, start heating up to 172°C, set the stirring speed to 80 - 120 r / min, preferably 100 r / min, and then add diethylenetriamine.

[0012] Further, the amine value of the high-temperature oil-based drilling fluid integrated emulsifier obtained in Step 2 is 8.5 - 11.3. The unit of amine value in this application document is mgKOH / g.

[0013] Further, the high-temperature oil-based drilling fluid integrated emulsifier obtained in Step 2 can withstand a temperature of up to 220°C.

[0014] The plant asphalt undergoes an esterification reaction under the action of concentrated sulfuric acid, and then diethylenetriamine is added. When the temperature is raised to 172°C - 176°C, comprehensive reactions such as amidation, amide exchange, and esterification occur. Continue heating up to 186°C - 190°C to make the amidation reaction more complete; however, it is not advisable to react for too long within the temperature range of 186°C - 190°C, as it will cause the previously formed esterification products to decompose. The high-temperature oil-based drilling fluid integrated emulsifier of the present invention is an emulsifier product that combines the functions of a main emulsifier and an auxiliary emulsifier. The main emulsifier component is mainly the high-level mixed ester therein, while the auxiliary emulsifier component is mainly polyamide. The combination of the two brings excellent emulsification stability.

[0015] The plant asphalt is the waste residue in the process of vegetable oil processing, containing components such as higher fatty acids, phytol, vegetable oil, vitamin E, wax, etc. The component with the highest content is higher fatty acids, and it is commonly used as a binder. The acid value of the plant asphalt is 80 - 90, preferably 85 ± 2. The unit of acid value in this application document is mgKOH / g.

[0016] The present invention also provides a high-temperature oil-based drilling fluid prepared by formulating the above high-temperature oil-based drilling fluid integrated emulsifier. The high-temperature oil-based drilling fluid includes: white oil, the high-temperature oil-based drilling fluid integrated emulsifier, calcium chloride aqueous solution, and a high-temperature filtration loss reducer, and may further include a viscosifier, an alkalinity regulator, a weighting agent, and a plugging agent.

[0017] In the high-temperature oil-based drilling fluid, the oil-water ratio is (69 - 88):(12 - 31), and the mass percentage of calcium chloride in the mud is not higher than 13%.

[0018] In the high-temperature oil-based drilling fluid, the mass percentage of the high-temperature oil-based drilling fluid integrated emulsifier in the mud is 1% - 5%.

[0019] The high-temperature filtration loss reducer may be modified lignite, such as sulfonated lignite; the viscosifier may be organophilic clay; the alkalinity regulator may be calcium oxide; the weighting agent may be barite; the plugging agent may be a mixture of nut shell particles.

[0020] This application mainly uses the low-cost environmental protection raw material plant asphalt, and the proportion of the relatively higher-priced diethylenetriamine is not higher than 5%. This is both to reduce production costs and to increase the degree of amidation reaction and reduce the amine value of the emulsifier system (a high amine value of the emulsifier system has an inhibitory effect on the water-in-oil emulsion system). Through two reasonable reaction processes, the conversion rates of the esterification reaction and the amidation reaction are increased, and the effective components (mainly higher mixed esters, polyamides, a small amount of higher mixed acids, higher mixed alcohols, and other complex organic compounds containing oxygen elements) of the high-temperature oil-based drilling fluid integrated emulsifier can reach about 80%. The non-effective components are mainly hydrocarbons and hydrocarbon-like compounds with very few elements other than carbon and hydrogen in the molecule, and the proportion of macromolecular organic amine salts is very small. The overall compatibility of the non-effective components with petroleum hydrocarbons is relatively high, which neither significantly affects the emulsification use effect nor harms the oil layer.

[0021] The high-temperature oil-based drilling fluid integrated emulsifier of this application is an oil-based drilling fluid high-temperature emulsifier that combines the functions of a main emulsifier and an auxiliary emulsifier. The main emulsifier component is mainly the higher mixed esters therein, and the auxiliary emulsifier component is mainly polyamide. This product has good stability, a relatively high demulsification voltage, and can withstand a temperature of up to 220°C. It has good emulsifying properties and filtration loss reduction properties. The rheology and dynamic and static shear forces of the oil-based drilling fluid prepared with the high-temperature oil-based drilling fluid integrated emulsifier of this application are also good, which can meet the working performance requirements of the oil-based drilling fluid and effectively reduce costs. Specific Embodiments

[0022] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0023] The present invention provides a technical solution: a low-cost high-temperature oil-based drilling fluid integrated emulsifier.

[0024] The main raw material, plant asphalt, is purchased from Dongying Huazhi Chemical New Materials Co., Ltd.

[0025] Example 1:

[0026] This emulsifier is made from the following raw materials: 9.47 kg of plant asphalt (acid value 85 ± 2), 0.03 kg of 98 wt% concentrated sulfuric acid, and 0.50 kg of diethylenetriamine. The total of the above components is 10.0 kg.

[0027] It is obtained by the following method:

[0028] Weigh the raw materials according to the ratio. Add 9.47 kg of plant asphalt (acid value 85 ± 2) into the reaction kettle, start heating. When the temperature reaches 138°C, start stirring at a speed of 160 r / min, and dropwise add 0.03 kg of 98 wt% concentrated sulfuric acid. After dropping, let it react at a temperature of 138°C - 140°C for 2.5 h; after the reaction is completed, start heating up. When the temperature rises to 172°C, reduce the stirring speed to 100 r / min, add 0.50 kg of diethylenetriamine, first let it react in the temperature range of 172°C - 176°C for 2.5 h. After the reaction is completed, start heating up to 186°C, and then let it react in the temperature range of 186°C - 190°C for 1.0 h while starting vacuum dehydration. After that, no more water comes out of the reaction kettle; cool to room temperature, and the obtained black paste is the low-cost high-temperature oil-based drilling fluid integrated emulsifier sample. The amine value of the sample is detected to be 10.3. The amine value is determined by the hydrochloric acid - isopropanol titration method, which will not be elaborated below.

[0029] After that, performance tests are carried out on the sample. Each example is tested by the following method:

[0030] 1. High-temperature emulsification rate measurement method

[0031] Weigh 26.00 g (accurate to 0.01 g) of calcium chloride and place it in a 100 mL beaker. Measure 74 mL of distilled water and add it to the beaker containing calcium chloride solid. Stir to dissolve and prepare a 26 wt% calcium chloride solution. Weigh 6.00 g of the emulsifier sample (prepared by the present invention) and place it in a high-speed stirring cup. Measure 240 mL of No. 3 white oil and add it to the high-speed stirring cup containing the emulsifier sample. Stir at a high speed of 10000 r / min for 5 min, then slowly add 9.00 g of calcium oxide. Stir at a high speed of 10000 r / min for 5 min, add 60 mL of 26 wt% calcium chloride solution, and stir at a high speed for 20 min. Then put it into an aging tank and place it in a roller heating furnace, and heat roll at 220 °C for 16 h to prepare a water-in-oil emulsion. Finally, take out the water-in-oil emulsion after constant temperature rolling, cool it to about 50 °C and keep the temperature at 50 ± 1 °C, stir at a high speed for 20 min, pour it to the highest scale line of a 250 mL graduated cylinder, let it stand and observe, and read the number of milliliters of the oil layer separated in 10 min. Calculate the emulsification rate according to the formula E = 250 - V / 250. (In the formula, E is the emulsification rate, and V is the number of milliliters of the oil layer separated in 10 min)

[0032] 2. Determination of the comprehensive emulsification performance of the experimental mud of oil-based drilling fluid

[0033] In order to evaluate the important performance of the emulsifier of the present invention, we prepared an oil-based drilling fluid with it for testing. The basic formula of the oil-based drilling fluid is: 255 ml of No. 3 white oil + 6 g of emulsifier (prepared by the present invention) + 45 ml of 26 wt% CaCl2 aqueous solution + 3 g of organophilic clay + 15 g of CaO + 6 g of high-temperature filtration loss reducer (modified lignite, XP-20N product from Schlumberger) + 12 g of barite. Put the prepared experimental slurry into an aging tank, place it in a roller heating furnace, heat roll at 220 °C for 16 h, take it out and cool it to the required temperature, stir at a speed of 1000 r / min for 5 min, and then determine the demulsification voltage, plastic viscosity, yield point, gel strength, high-temperature high-pressure filtration loss of the experimental slurry of the oil-based drilling fluid after heat rolling at 220 °C according to the basic method of GB / T 16783.2—2012 "Petroleum and natural gas industries - Drilling fluids - Field testing - Part 2: Oil-based drilling fluids", and determine the interfacial tension of the experimental slurry of the oil-based drilling fluid after heat rolling at 220 °C according to the method of SY / T5730-2018 "Determination method of surface and interfacial tension".

[0034] The test data of each index of the emulsifier sample prepared in Example 1 are shown in Table 1 below:

[0035] Table 1

[0036]

[0037] As can be seen from the results in Table 1, the performance of the emulsifier sample prepared in Example 1 is excellent.

[0038] Example 2:

[0039] This emulsifier is made from the following raw materials: 9.54 kg of plant asphalt (acid value 85 ± 2), 0.03 kg of 98 wt% concentrated sulfuric acid, and 0.43 kg of diethylenetriamine. The total of the above components is 10.0 kg.

[0040] It is obtained by the following method:

[0041] Weigh the raw materials according to the ratio. Add 9.54 kg of plant asphalt (acid value 85 ± 2) into the reaction kettle, turn on the heating. When the temperature reaches 138 °C, start stirring at a speed of 160 r / min, and dropwise add 0.03 kg of 98 wt% concentrated sulfuric acid. After dropping, let it react at a temperature of 138 °C - 140 °C for 2.5 h; after the reaction is completed, turn on the temperature increase. When the temperature rises to 172 °C, reduce the stirring speed to 100 r / min, add 0.43 kg of diethylenetriamine, first let it react in the temperature range of 172 °C - 176 °C for 2.5 h. After the reaction is completed, turn on the temperature increase to 186 °C, and then let it react in the temperature range of 186 °C - 190 °C for 1.0 h while starting vacuum dehydration. After that, no more water comes out of the reaction kettle; cool to room temperature, and the obtained black paste is the sample of the high-temperature oil-based drilling fluid integrated emulsifier with low cost. The amine value of the sample is detected to be 8.9.

[0042] The test data of each index of the emulsifier sample prepared in Example 2 are shown in Table 2 below:

[0043] Table 2

[0044]

[0045]

[0046] As can be seen from the results in Table 2, the performance of the emulsifier sample prepared in Example 2 is excellent.

[0047] Example 3:

[0048] This emulsifier is made from the following raw materials: 9.45 kg of plant asphalt (acid value 85 ± 2), 0.03 kg of 98 wt% concentrated sulfuric acid, and 0.52 kg of diethylenetriamine. The total of the above components is 10.0 kg.

[0049] It is obtained by the following method:

[0050] Weigh the raw materials according to the ratio. Add 9.45 kg of plant asphalt (acid value: 85 ± 2) into the reaction kettle, start heating. When the temperature reaches 138 °C, start stirring at a speed of 160 r / min, and dropwise add 0.03 kg of 98 wt% concentrated sulfuric acid. After dropping, make it react at a temperature of 138 °C - 140 °C for 2.5 h; after the reaction is completed, start heating up. When the temperature rises to 172 °C, reduce the stirring speed to 100 r / min, add 0.52 kg of diethylenetriamine, first make it react in the temperature range of 172 °C - 176 °C for 2.5 h. After the reaction is completed, start heating up to 186 °C, then make it react in the temperature range of 186 °C - 190 °C for 1.0 h while starting vacuum dehydration, and then no more water comes out of the reaction kettle; cool to room temperature, and the obtained black paste is the sample of the low-cost high-temperature oil-based drilling fluid integrated emulsifier. The amine value of the sample is detected to be 12.4.

[0051] The test data of each index of the emulsifier sample prepared in Example 3 are shown in Table 3 below:

[0052] Table 3

[0053]

[0054] As can be seen from the results in Table 3, the emulsification rate (<90%) of the emulsifier sample prepared in Example 3 in the experimental slurry is unqualified, the demulsification voltage (<500 V) has a deviation, and the high-temperature and high-pressure filtration loss (>15 mL) is unqualified. The performance of the emulsifier sample prepared in Example 3 cannot well meet the application requirements. The reason for the unqualified emulsification rate of the emulsifier sample prepared in Example 3 is that its amine value exceeds the stable critical point of 11.3 of the emulsifier system of this application. When the amine value of the emulsifier system of this application exceeds 11.3, its high-temperature emulsification stability will be significantly reduced, and the high-temperature demulsification voltage and emulsification rate will both decrease accordingly. At the same time, it will bring about a decrease in the viscosity of the mud system. After the high-temperature emulsification stability and viscosity decrease, the high-temperature and high-pressure filtration loss will increase accordingly. Regarding the amine value critical point phenomenon, we guess that because the amino group belongs to a hydrophilic group, when its content exceeds the critical point, it has an inhibitory effect on the water-in-oil emulsion structure or the emulsion film at the oil-water interface. Therefore, the maximum addition amount of diethylenetriamine can only reach 5.0%.

[0055] Example 4:

[0056] This emulsifier is made from the following raw materials: 9.51 kg of plant asphalt (acid value: 85 ± 2), 0.03 kg of 98 wt% concentrated sulfuric acid, 0.46 kg of diethylenetriamine, and the total of the above components is 10.0 kg.

[0057] It is obtained by the following method:

[0058] Weigh the raw materials according to the ratio. Add 9.51 kg of plant asphalt (acid value is 85 ± 2) into the reaction kettle, turn on the heating. When the temperature reaches 138 °C, start stirring at a speed of 160 r / min, and dropwise add 0.03 kg of 98 wt% concentrated sulfuric acid. After dropping, make it react at a temperature of 138 °C - 140 °C for 2.5 h; after the reaction is completed, start heating up. When the temperature rises to 172 °C, reduce the stirring speed to 100 r / min, add 0.46 kg of diethylenetriamine, first make it react in the temperature range of 172 °C - 176 °C for 2.5 h. After the reaction is completed, start heating up to 186 °C, and then make it react in the temperature range of 186 °C - 190 °C for 1.0 h while starting vacuum dehydration. After that, no more water comes out of the reaction kettle; the black paste obtained after cooling to room temperature is the sample of the low-cost high-temperature oil-based drilling fluid integrated emulsifier, and the amine value of the sample is detected to be 9.5.

[0059] The test data of each index of the emulsifier sample prepared in Example 4 are shown in Table 4 below:

[0060] Table 4

[0061]

[0062]

[0063] As can be seen from the results in Table 4, the performance of the emulsifier sample prepared in Example 4 is excellent.

[0064] Example 5:

[0065] This emulsifier is made from the following raw materials: 9.51 kg of plant asphalt (acid value is 85 ± 2), 0.03 kg of 98 wt% concentrated sulfuric acid, 0.46 kg of diethylenetriamine, and the total of the above components is 10.0 kg.

[0066] It is obtained by the following method:

[0067] Weigh the raw materials according to the ratio. Add 9.51 kg of plant asphalt (acid value is 85 ± 2) into the reaction kettle, turn on the heating. When the temperature reaches 138 °C, start stirring at a speed of 160 r / min, and dropwise add 0.03 kg of 98 wt% concentrated sulfuric acid. After dropping, make it react at a temperature of 138 °C - 140 °C for 2.5 h; after the reaction is completed, start heating up. When the temperature rises to 172 °C, reduce the stirring speed to 100 r / min, add 0.46 kg of diethylenetriamine, first make it react in the temperature range of 172 °C - 176 °C for 2.5 h. After the reaction is completed, start heating up to 186 °C, and then make it react in the temperature range of 186 °C - 190 °C for 1.5 h while starting vacuum dehydration. After that, no more water comes out of the reaction kettle; the black paste obtained after cooling to room temperature is the sample of the low-cost high-temperature oil-based drilling fluid integrated emulsifier, and the amine value of the sample is detected to be 9.3.

[0068] The test data of each index of the emulsifier sample prepared in Example 5 are shown in Table 5 below:

[0069] Table 5

[0070]

[0071] In Example 5 and Example 4, the types and proportions of the selected raw materials are the same. The difference in the process is only that it reacts for an additional 0.5 h in the temperature range of 186°C - 190°C. It can be seen from the results in Table 5 that the emulsification rate of the emulsifier sample prepared in Example 5 in the experimental pulp is significantly lower than that in Example 4, while the changes in other indexes are not too large. We found that when the total reaction time in the temperature range of 186°C - 191°C in the second step of the process of this application exceeds 1.0 h, the emulsification rate will decrease. We don't know the exact reason. It is speculated that the decomposition amount of some esters with poor thermal stability increases with the extension of the reaction temperature time of 186°C - 190°C, or the generation amount of other substances unfavorable to the emulsification rate increases.

[0072] Example 6:

[0073] This emulsifier is made from the following raw materials: 9.51 kg of plant asphalt (acid value 51 ± 2), 0.03 kg of 98 wt% concentrated sulfuric acid, and 0.46 kg of diethylenetriamine. The total of the above components is 10.0 kg.

[0074] It is obtained by the following method:

[0075] Weigh the raw materials according to the ratio. Add 9.51 kg of plant asphalt (acid value 51 ± 2) into the reaction kettle, turn on the heating. When the temperature reaches 138°C, start stirring at a speed of 160 r / min, and drop 0.03 kg of 98 wt% concentrated sulfuric acid. After dropping, let it react at a temperature of 138°C - 140°C for 2.5 h; after the reaction is completed, start heating up. When the temperature rises to 172°C, reduce the stirring speed to 100 r / min, add 0.46 kg of diethylenetriamine, first let it react in the temperature range of 172°C - 176°C for 2.5 h. After the reaction is completed, start heating up to 186°C, and then let it react in the temperature range of 186°C - 190°C for 1.0 h while starting vacuum dehydration. After that, no more water comes out of the reaction kettle; cool it to room temperature, and the obtained black paste is the sample of the low-cost high-temperature oil-based drilling fluid integrated emulsifier. The amine value of the sample is detected to be 29.7.

[0076] The test data of the emulsification rate index of the emulsifier sample prepared in Example 6 are shown in Table 6 below:

[0077] Table 6

[0078] Test items (after aging at 220 °C for 16 h) Test results Emulsification rate (50 ± 1 °C), % 58.4

[0079] The plant asphalt selected in this embodiment is not the plant asphalt with an acid value of 85±2 selected in Embodiments 1 to 5, but the plant asphalt with an acid value of 51±2. As can be seen from the results in Table 6, the emulsification rate of the emulsifier sample prepared in Example 6 is only 58.4%. Since the emulsification rate of the sample in Example 6 fails seriously and its emulsification phenomenon is also unstable, it is an absolutely failed sample. Therefore, we did not test other indicators. It was detected that the amine value of the sample reached 29.7, which also shows from the side that there are still many amine groups in diethylenetriamine that did not participate in the amidation reaction. After many experiments, we finally determined that the plant asphalt of this application can only select the plant asphalt with an acid value in the range of 80-90, and preferably the plant asphalt with an acid value of 85±2.

[0080] According to multiple groups of embodiments, we found that when the proportion of diethylenetriamine exceeds 5.0%, the comprehensive performance of the obtained emulsifier will decrease significantly. When the proportion of diethylenetriamine is within 5.0% but the reaction time exceeds 1.0 h at a temperature of 186°C - 190°C, the emulsification rate of the obtained emulsifier will decrease. Generally, the lower the amine value within a certain range, the better the emulsification stability and the higher the demulsification voltage value. There is no absolutely optimal process formula in this application, but Example 4 can be said to be the relatively optimal process formula with the best comprehensiveness. Its emulsification rate value is the highest, and the demulsification voltage, plastic viscosity, dynamic shear force, static shear force, high-temperature high-pressure filtration loss, and interfacial tension are also within the excellent value range, which can well meet the performance requirements of 220°C high-temperature oil-based drilling fluid.

[0081] The above description of the embodiments is for the convenience of those of ordinary skill in the art to understand and use the present invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative labor. Therefore, the present invention is not limited to the above embodiments. Those skilled in the art should make improvements and modifications within the scope of the present invention based on the principles of the present invention without departing from the scope of the present invention. The above is only the preferred embodiments of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-temperature oil-based drilling fluid integrated emulsifier, characterized in that: Made of the following raw materials in percentage by weight: 94.7%-95.4% of plant asphalt, 4.3%-5.0% of diethylenetriamine, and 0.3% of 98wt% concentrated sulfuric acid; the acid value of the plant asphalt is 80-90; The preparation method thereof comprises the following steps: Step 1: weigh the raw materials according to the ratio, add the vegetable asphalt into the reactor, turn on the heating and stirring, and drop 98wt% concentrated sulfuric acid. After the drop is completed, react at a temperature of 138℃-140℃ for 2.0-3.0h; Step 2: Start heating, add diethylenetriamine into the reactor, first react it in the temperature range of 172°C-176°C for 2.0-3.0h, after the reaction is completed, continue to heat and start vacuum dehydration, and then react it in the temperature range of 186°C-190°C for 0.5-1.0h until the reactor no longer discharges water; cool to room temperature to obtain the high-temperature oil-based drilling fluid integrated emulsifier; the amine value of the high-temperature oil-based drilling fluid integrated emulsifier obtained in step 2 is 8.5-11.

3.

2. The high-temperature oil-based drilling fluid integrated emulsifier according to claim 1, characterized in that: The acid value of the vegetable asphalt is 85±2.

3. The high-temperature oil-based drilling fluid integrated emulsifier according to claim 1, characterized in that: Step 1, react at a temperature of 138°C-140°C for 2.5 hours; Step 2, first react at a temperature range of 172°C-176°C for 2.5 hours, and then react at a temperature range of 186°C-190°C for 1.0 hour.

4. The high-temperature oil-based drilling fluid integrated emulsifier according to claim 1, characterized in that: Step 1: Turn on the heating to 138°C, set the stirring speed to 140-200 r / min, and then dropwise add 98wt% concentrated sulfuric acid; and / or Step 2: Heat to 172°C, set the stirring speed to 80-120 r / min, and then add diethylenetriamine.

5. The high-temperature oil-based drilling fluid integrated emulsifier according to claim 1, characterized in that: Step 1: Turn on the heating to 138°C, set the stirring speed to 160r / min, and then dropwise add 98wt% concentrated sulfuric acid; and / or Step 2: Heat to 172°C, set the stirring speed to 100 r / min, and then add diethylenetriamine.

6. The high-temperature oil-based drilling fluid integrated emulsifier according to claim 1, characterized in that: The high-temperature oil-based drilling fluid integrated emulsifier obtained in step 2 has a temperature resistance of up to 220°C.

7. A high temperature oil-based drilling fluid, characterized in that: The high-temperature oil-based drilling fluid comprises: white oil, the high-temperature oil-based drilling fluid integrated emulsifier according to any one of claims 1 to 6, a calcium chloride aqueous solution and a high-temperature fluid loss reducer.

8. The high temperature oil-based drilling fluid according to claim 7, characterized in that: In the high-temperature oil-based drilling fluid, the oil-water ratio is (69-88): (12-31), and the mass percentage of calcium chloride in the mud is not higher than 13%.

9. The high temperature oil-based drilling fluid according to claim 7, characterized in that: In the high-temperature oil-based drilling fluid, the mass percentage of the high-temperature oil-based drilling fluid integrated emulsifier in the mud is 1%-5%.

10. The high temperature oil-based drilling fluid according to claim 7, characterized in that: The high temperature oil-based drilling fluid also includes a viscosity enhancer, an alkalinity regulator, a weighting agent and a plugging agent.

11. The high temperature oil-based drilling fluid according to claim 10, characterized in that: The high-temperature fluid loss reducer is modified lignite; the viscosity enhancer is organic soil; the alkalinity regulator is calcium oxide; the weighting agent is barite; and the plugging agent is a mixture of nut shell particles.

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