A drag-reducing and freezing-point-lowering agent, its preparation method and application

Abstract

This invention relates to the field of oil and gas field technology, and proposes a drag-reducing and pour point depressant, its preparation method, and its application. The drag-reducing and pour point depressant comprises the following raw materials in parts by weight: 40-60 parts α-olefin polymer, 10-30 parts pour point depressant, 10-20 parts viscosity modifier, 0.1-1 part surfactant, 70-90 parts alcohol-water mixed solvent, 10-20 parts additives, and 3-5 parts nano-diatomaceous earth; the additives are methyl formate benzenesulfonamide and o-aminoacetophenone. This technical solution solves the problem that existing drag-reducing and pour point depressants have limited functionality and cannot cope with the diverse types of crude oil and varied transportation conditions.

Description

Technical Field

[0001] This invention relates to the field of oil and gas field technology, specifically to a drag-reducing and pour point depressant, its preparation method, and its application. Background Technology

[0002] Crude oil, with its high viscosity and density, generates significant frictional resistance during pipeline transportation, leading to decreased flow properties. Furthermore, crude oil is susceptible to temperature fluctuations during transport, causing cooling, condensation, and sedimentation, increasing transportation costs. Therefore, adding drag-reducing and pour point-depressing agents is the most effective method for ensuring smooth crude oil transportation. my country boasts a relatively diverse range of crude oil types, primarily from the Ordos Basin, Daqing Oilfield, Northwest Sichuan Oil and Gas Field, and Bohai Bay offshore oilfields. These crude oils vary in geological composition, viscosity, density, and sulfur content, and transportation conditions are diverse. China's crude oil transportation methods encompass onshore pipelines, offshore pipelines, railways, highways, and waterways. The varying transportation distances between different regions, along with the unique characteristics of transportation environments, climates, and temperatures, necessitate drag-reducing and pour point-depressing agents capable of adapting to diverse transportation conditions to ensure smooth and safe crude oil transportation. Therefore, developing multifunctional drag-reducing and pour point-depressing agents with drag-reducing, pour point-depressing, pipeline cleaning, and crude oil quality improvement capabilities is a pressing issue that needs to be addressed. Summary of the Invention

[0003] This invention proposes a drag-reducing and pour point depressant, its preparation method, and its application, which solves the problem that drag-reducing and pour point depressants in related technologies have a single function and cannot cope with the variety of crude oil types and transportation conditions.

[0004] The technical solution of the present invention is as follows: The present invention proposes a drag-reducing and pour point depressant, comprising the following raw materials in parts by weight: 40-60 parts of α-olefin polymer, 10-30 parts of pour point depressant, 10-20 parts of viscosity modifier, 0.1-1 parts of surfactant, 70-90 parts of alcohol-water mixed solvent, 10-20 parts of additives, and 3-5 parts of nano diatomaceous earth; The additives are methyl formate benzenesulfonamide and o-aminoacetophenone.

[0005] As a further technical solution, the pour point depressant is polyacrylate, the viscosity modifier is an acrylic copolymer, and the alcohol-water mixed solvent is a mixed solvent of ethanol and water in a volume ratio of 1:1 to 3.

[0006] As a further technical solution, the mass ratio of methyl formate benzenesulfonamide and o-aminoacetophenone is 1:2~4.

[0007] As a further technical solution, the surfactant is one or more of ethylene oxide, sodium alkyl sulfonate, and epoxy resin alcohol.

[0008] As a further technical solution, the particle size of the nano-diatomite is 150nm~200nm.

[0009] As a further technical solution, the nano-diatomite is modified nano-diatomite, and the modifier of the modified nano-diatomite is methyl perfluorohexadecanoate, and the mass ratio of methyl perfluorohexadecanoate to the nano-diatomite is 1:20~50.

[0010] In this invention, nano-diatomite is surface-modified with perfluoromethyl hexadecanoate to reduce its interaction with polar substances (such as lipophilic components in crude oil), thereby achieving hydrophobic modification and reducing the absorption of some crude oil by nano-diatomite to form a gel-like substance, thus reducing the increase in crude oil viscosity.

[0011] As a further technical solution, the preparation method of the drag-reducing and pour point depressant includes the following steps: S1. The α-olefin polymer, pour point depressant, and viscosity modifier are mechanically mixed to obtain a solid mixture powder. S2. Stir the solid mixture powder, surfactant, alcohol-water mixture, additives and modified nano-diatomaceous earth at room temperature to prepare a multifunctional drag-reducing and pour point depressant.

[0012] As a further technical solution, the mechanical mixing is a low-temperature pulverization mixing, carried out at -50℃ to -130℃.

[0013] As a further technical solution, the stirring time is 30 min to 60 min, and the stirring speed is 200 to 300 r / min.

[0014] As a further technical solution, the drag-reducing and pour point depressant described herein or the drag-reducing and pour point depressant prepared by the method described herein is applied in crude oil transportation.

[0015] The working principle and beneficial effects of this invention are as follows: In this invention, the sulfonamide functional groups in the additive methyl phthalate benzenesulfonamide not only form a uniform protective film between crude oil and the pipeline wall, thereby reducing the frictional resistance of crude oil in the pipeline, improving fluid flow, and reducing energy loss, but also possess certain anti-corrosion properties, protecting the pipeline wall from corrosion damage, extending pipeline life, and reducing maintenance costs. The amino functional groups in o-aminoacetophenone react chemically with oxides and acids in crude oil to form salts or mixtures, inhibiting crystallization. Nano-diatomaceous earth, as an adsorbent, can adsorb impurities and water molecules suspended in crude oil, promoting rapid separation of crude oil and water, improving oil-water separation efficiency, reducing potential pollution problems during pipeline transportation, preventing precipitation and oxidation reactions during transportation, and maintaining the quality of crude oil. Detailed Implementation

[0016] 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.

[0017] Example 1 A drag-reducing and pour point depressant, its preparation method, and its application, comprising the following steps: S1. Weigh 40 parts of α-olefin polymer, 10 parts of pour point depressant, and 10 parts of viscosity modifier, add them to a cryogenic pulverizer, and mechanically mix them at -50℃ to -130℃ to obtain a solid mixture powder.

[0018] S2. Add the obtained solid mixture powder, 0.1 parts of ethylene oxide, 70 parts of alcohol-water mixed solution (ethanol and water volume ratio of 1:1), 10 parts of additives (5 parts of methyl formate benzenesulfonamide and 5 parts of anthranilone), and 3 parts of nano diatomaceous earth into a flask, and stir at 200 r / min for 30 min at room temperature to obtain drag-reducing and pour point depressant.

[0019] Example 2 A drag-reducing and pour point depressant, its preparation method, and its application, comprising the following steps: S1. Weigh 50 parts of α-olefin polymer, 20 parts of pour point depressant, and 15 parts of viscosity modifier, add them to a cryogenic pulverizer, and mechanically mix them at -50℃ to -130℃ to obtain a solid mixture powder.

[0020] S2. Add the obtained solid mixture powder, 0.5 parts of sodium alkyl sulfonate, 80 parts of alcohol-water mixed solution (ethanol and water volume ratio of 1:2), 12 parts of additives (6 parts of methyl methacrylate benzenesulfonamide and 6 parts of anthranilone), and 4 parts of nano diatomaceous earth into a flask, and stir at 250 r / min for 45 min at room temperature to obtain drag-reducing and pour point depressant.

[0021] Example 3 A drag-reducing and pour point depressant, its preparation method, and its application, comprising the following steps: S1. Weigh 60 parts of α-olefin polymer, 30 parts of pour point depressant, and 20 parts of viscosity modifier, add them to a cryogenic pulverizer, and mechanically mix them at -50℃ to -130℃ to obtain a solid mixture powder.

[0022] S2. Add the obtained solid mixture powder, 1 part of epoxy resin alcohol, 90 parts of alcohol-water mixture (ethanol and water volume ratio of 1:3), 20 parts of additives (10 parts of methyl methacrylate benzenesulfonamide and 10 parts of anthranilone), and 5 parts of nano diatomaceous earth into a flask, and stir at 300 r / min for 60 min at room temperature to obtain drag-reducing and pour point depressant.

[0023] Example 4 Compared with Example 2, Example 4 differs in that 12 parts of the adjuvant (6 parts of methyl formate benzenesulfonamide and 6 parts of o-aminoacetophenone) are replaced with 2 parts of methyl formate benzenesulfonamide and 10 parts of o-aminoacetophenone.

[0024] Example 5 Compared with Example 2, Example 5 differs in that 12 parts of the adjuvant (6 parts of methyl formate benzenesulfonamide and 6 parts of o-aminoacetophenone) are replaced with 4 parts of methyl formate benzenesulfonamide and 8 parts of o-aminoacetophenone.

[0025] Example 6 Compared with Example 2, Example 6 differs in that 12 parts of the adjuvant (6 parts of methyl formate benzenesulfonamide and 6 parts of o-aminoacetophenone) are replaced with 3 parts of methyl formate benzenesulfonamide and 9 parts of o-aminoacetophenone.

[0026] Example 7 Compared with Example 2, Example 7 differs in that 12 parts of the adjuvant (6 parts of methyl formate benzenesulfonamide and 6 parts of o-aminoacetophenone) are replaced with 2.4 parts of methyl formate benzenesulfonamide and 9.6 parts of o-aminoacetophenone.

[0027] Example 8 Compared with Example 6, Example 8 differs in that the nano-diatomaceous earth is replaced with an equal amount of modified nano-diatomaceous earth, wherein the mass ratio of perfluorohexadecanoate to the nano-diatomaceous earth is 1:20. The modification method is as follows: 4 parts of nano-diatomaceous earth are coated with 0.2 parts of perfluorohexadecanoate at 60℃~70℃ for 30 minutes, and after sufficient cooling, after a 5-day storage period, the modified nano-diatomaceous earth is obtained.

[0028] Example 9 The difference between Example 9 and Example 8 is that the mass ratio of perfluorohexadecanoate to the nano-diatomaceous earth is 1:40.

[0029] Example 10 The difference between Example 10 and Example 9 is that the mass ratio of perfluorohexadecanoate to the nano-diatomite is 1:50.

[0030] Comparative Example 1 The difference between Comparative Example 1 and Example 2 is that no additives were added.

[0031] Comparative Example 2 Compared with Example 2, Comparative Example 2 differs in that 12 parts of the adjuvant (6 parts of methyl formate benzenesulfonamide and 6 parts of o-aminoacetophenone) were replaced with 12 parts of methyl formate benzenesulfonamide.

[0032] Comparative Example 3 Compared with Example 2, Comparative Example 3 differs in that 12 parts of the adjuvant (6 parts of methyl phthalate benzenesulfonamide and 6 parts of o-aminoacetophenone) were replaced with 12 parts of o-aminoacetophenone.

[0033] The drag-reducing and pour point depressing agents prepared in Examples 1-10 and Comparative Examples 1-3 were tested according to the following method: 1. Drag Reduction Rate: The prepared drag-reducing and pour point depressant was dissolved in diesel oil and added to crude oil. The drag reduction effect of the product was evaluated on a ring drag reduction test device. 2. Pour point depressant: Referring to standard GB / T3535 "Petroleum Products Determination of Pour Point", the bifunctional drag reducer was added to the high wax crude oil sample at 50 ppm, stirred slowly at 65℃ for 30 min, then subjected to programmed cooling treatment, and then the pour point test was performed to determine the pour point depressant effect of the drag reducer.

[0034] The test results are shown in the table below: Table 1. Drag reduction rate test results of drag-reducing and pour point depressants prepared in Examples 1-10 and Comparative Examples 1-3

[0035] Table 2. Results of pour point depressing tests on drag-reducing and pour point depressing agents prepared in Examples 1-10 and Comparative Examples 1-3.

[0036] Compared with Comparative Examples 1-3, Examples 1-3 added methyl formate benzenesulfonamide and o-aminoacetophenone in different mass ratios. The results showed that Examples 1-3 had increased drag reduction rate and decreased pour point in different crude oils, indicating that methyl formate benzenesulfonamide and o-aminoacetophenone have a synergistic effect, which can further reduce the drag in different types of crude oil and transportation conditions, while increasing the pour point of crude oil. This improves the problem that drag-reducing and pour point depressing agents have a single function and cannot cope with the variety of crude oil types and transportation conditions.

[0037] Compared with Example 2, the mass ratio of methyl phthalate benzenesulfonamide and o-aminoacetophenone in Examples 4-7 is different. As a result, the drag reduction rate of Examples 5-7 is higher than that of Examples 2 and 4, and the pour point is lower than that of Examples 2 and 4. This indicates that when the mass ratio of methyl phthalate benzenesulfonamide and o-aminoacetophenone is 1:2 to 4, and preferably 1:3, the drag reduction rate of crude oil transportation can be further improved and the pour point of crude oil can be reduced.

[0038] Compared with Example 6, Examples 8-10 used nano-diatomaceous earth modified with different masses of perfluorohexadecanoate methyl ester. The results showed that Example 9 had the highest drag reduction rate and the lowest pour point, indicating that when the mass ratio of perfluorohexadecanoate methyl ester to nano-diatomaceous earth was 1:40, the modified nano-diatomaceous earth obtained had the best drag reduction and pour point depressing effect when applied to drag-reducing and pour point depressing agents.

[0039] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A drag-reducing and pour point depressant, characterized in that, The composition by weight is as follows: 40-60 parts of α-olefin polymer, 10-30 parts of pour point depressant, 10-20 parts of viscosity modifier, 0.1-1 part of surfactant, 70-90 parts of alcohol-water mixed solvent, 10-20 parts of additives, and 3-5 parts of nano-diatomaceous earth; The additives are methyl formate benzenesulfonamide and o-aminoacetophenone; The mass ratio of methyl formate benzenesulfonamide and o-aminoacetophenone is 1:2~4; The nano-diatomite is modified nano-diatomite, and the modifier of the modified nano-diatomite is methyl perfluorohexadecanoate, and the mass ratio of methyl perfluorohexadecanoate to the nano-diatomite is 1:20~50. The surfactant is one or both of ethylene oxide and sodium alkyl sulfonate.

2. The drag-reducing and pour point depressant according to claim 1, characterized in that, The particle size of the nano-diatomite is 150nm~200nm.

3. A method for preparing a drag-reducing and pour point depressant according to any one of claims 1 to 2, characterized in that, Includes the following steps: S1. The α-olefin polymer, pour point depressant, and viscosity modifier are mechanically mixed to obtain a solid mixture powder. S2. The solid mixture powder, surfactant, alcohol-water mixed solvent, additives and modified nano-diatomaceous earth are stirred at room temperature to prepare drag-reducing and pour point depressant.

4. The method for preparing a drag-reducing and pour point depressant according to claim 3, characterized in that, The mechanical mixing is a low-temperature pulverization and mixing process, carried out at -50℃ to -130℃.

5. The method for preparing a drag-reducing and pour point depressant according to claim 3, characterized in that, The stirring time is 30 min to 60 min, and the stirring speed is 200 to 300 r / min.

6. The application of the drag-reducing and pour point depressant according to any one of claims 1 to 2 in crude oil transportation.

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