CN1360016A - Liquid pour depressor for crude and its preparing process - Google Patents
Liquid pour depressor for crude and its preparing process Download PDFInfo
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- CN1360016A CN1360016A CN 00135876 CN00135876A CN1360016A CN 1360016 A CN1360016 A CN 1360016A CN 00135876 CN00135876 CN 00135876 CN 00135876 A CN00135876 A CN 00135876A CN 1360016 A CN1360016 A CN 1360016A
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- vinyl acetate
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Abstract
A liquid pour depressor for the high-set point high-viscosity crude with high contents of wax, gum and asphalt is prepared from ethylene-vinyl acetate copolymer, higher alcohol acrylate-maleic acid anhydride-vinyl acetate polymer, higher alcohol acrylate polymer, epoxy resin, polyester and a special solvent.
Description
The present invention is used to a kind of liquid pour depressor for crude that improves the high pour point and viscous crude oil low-temperature fluidity and preparation method thereof, relates to the composition and the blending means technical field of macromolecular cpd.
In crude oil temperature drop process, macromole wax is separated out from crude oil gradually, and forms tridimensional network, oil is solidified, thereby influence its flowability, and this is a serious problem to pipeline transportation.For high pour point and viscous crude oil, adopt following several method to solve both at home and abroad usually: (1) is mixed thin oil and is carried method; (2) water emulsifying is carried method; (3) heating conveying method; (4) heat treating process; (5) add pour point depressant and carry method.At present, add safety, economical operation that pour point depressant for crude oil is realized long distance pipeline, be considered to one of state-of-the-art in the world crude pipeline transportation method, and pour point depressant for crude oil also has crucial application at the aspects such as exploitation of high pour point and viscous crude oil.
The kind and the quantity of the pour point depressant for crude oil of domestic and foreign literature and patent report are a lot, but pour point depressant for crude oil commonly used mainly contains following several types: ethene-vinyl acetate copolymer and derivative thereof, (methyl) vinylformic acid higher alcohols esters polymer and derivative thereof, vinylbenzene-maleic anhydride-vinylformic acid higher alcohols ester copolymer and derivative thereof, vinylformic acid high-carbon alcohol ester-maleic anhydride-vinyl acetate copolymer and derivative thereof.Chengdu Univ. of Science ﹠ Technology and Pipe Line Sciences Inst. of China Petroleum Natural Gas Corp. are ZL90105871.8 " waxy crude oil fluidity improver " in the patent No. of application on August 18 nineteen ninety, though adopted ethene-vinyl acetate copolymer and vinylformic acid higher alcohols ester copolymer composite, the pour point depression effect improves to some extent, but is only applicable to waxy crude oil.In the above-mentioned pour point depressant use, usually adopting diesel oil, gasoline, kerosene, toluene, dimethylbenzene is solvent, the liquid pour depressor for crude of preparation exists that flash-point is low, volatility is big and shortcoming such as viscosity height, cause on-the-spot injection difficulty, poor stability easily, even cause major accidents such as fire or burn-down of electric motor.And also there is following shortcoming in above-mentioned pour point depressant: (1) to the bad adaptability of different crude oils, a kind of pour point depressant is often effective to certain crude oil, and invalid to another kind of crude oil; (2) effective to the moderate crude Treatment of wax content, and the crude Treatment weak effect high to wax content, (3) are better to the waxy crude oil treatment effect, and to colloid, crude Treatment weak effect that asphalt content is high.
The purpose of this invention is to provide a kind of condensation point and apparent viscosity that can effectively reduce the moderate crude oil of wax content, again content of wax height or colloid, crude oil that asphalt content is high there are the fine effect of improving, and have that solubility property is good, viscosity is low, flash-point is high, volatility is little, the liquid pour depressor for crude of easy storage.
Liquid pour depressor for crude provided by the invention is the compound by multiple high molecular polymer and special solvent.High molecular polymer is by weight: ethylene-vinyl acetate copolymer 50-90%, vinylformic acid high-carbon alcohol ester-maleic anhydride-vinyl acetate polymer 0-10%, vinylformic acid higher alcohols ester polymer 5-15%, Resins, epoxy 0-25%, polyethers 0-25%.Therein ethylene-vinyl acetate copolymer, vinylformic acid high-carbon alcohol ester-maleic anhydride-vinyl acetate polymer, composite action effect and the sphere of action that has improved single pour point depressant to waxy crude oil of polyacrylic acid higher alcohols ester polymer make it can satisfy the requirement of different waxy crude oil; Resins, epoxy and polyethers react or hydrogen bond action by the functional group on colloid, the bituminous matter in polar functional group and the crude oil, form aggregate, thereby reduce the condensation point and the apparent viscosity of colloid, the high crude oil of asphalt content.Feature of the present invention is: vinyl acetate content is 25-40% in the high molecular polymer ethylene-vinyl acetate copolymer, and molecular weight is 8000-40000; Vinylformic acid high-carbon alcohol ester-maleic anhydride-vinyl acetate polymer is C
16-24Ester and maleic anhydride, vinyl acetate carry out copolyreaction and make, and its molecular weight is 5000-100000, and wherein maleic anhydride and vinyl acetate content are 5-15% and 2-10%; Vinylformic acid higher alcohols ester polymer is C
16-24The homopolymer of alcohol and acroleic acid esterification thing, its molecular weight is 10000-150000; Molecular weight of epoxy resin is 3000-20000, and the pfpe molecule amount is 2000-30000.Special solvent is by one or more composite the forming in different Fu Er ketone, tetraline, methyl phenyl ketone, heavy aromatics, butyl glycol ether and the ethylene glycol dibutyl ether.High molecular polymer and special solvent are in 1: the preparation of 2-20 ratio, preferable ratio is 1: 3-12.
Effect of the present invention depends on pour point depression effect and its physical and chemical performance of liquid pour point depressant.The pour-viscosity reduction effect of pour point depressant is relevant with influence factors such as pour point depressant proportioning, crude oil property, pour point depressant dosage, treatment temp, rate of temperature fall and final cooling temperatures, treatment temp generally is higher than condensation point of crude oil more than 25 ℃, and preferable temperature ranges is 60-100 ℃; The rate of temperature fall preferred range is 0.2-1.0 ℃/min, adds the 0.01-1.0% that pour point depression dosage is generally the crude oil weight ratio, and preferable dosage is 0.02-0.1%.Under top condition, pour point depressant provided by the invention can make the Daqing crude oil zero pour reduce to 14.0 ℃ by 32.0 ℃, can make the zero pour of the Sudan's crude oil reduce to 17.5 ℃ by 34.0 ℃; Can make depression of the freezing point 20 ℃ of Liaohe Oil Field viscous crude, apparent viscosity reduces by 68%, can make east face depression of the freezing point 18.0 ℃ of the defeated intermediate base crude oil of pipe, and apparent viscosity reduces about 85%.
The preparation method of liquid pour depressor for crude of the present invention can press step:
1. preparation special solvent
Press formula rate, one or more mixing with in high boiling point, the different Fu Er ketone of low volatile organic solvent, tetraline, methyl phenyl ketone, heavy aromatics, butyl glycol ether and the ethylene glycol dibutyl ether are mixed with special solvent.
2. preparation liquid pour depressor for crude
Press formula rate, earlier solid-state ethylene-vinyl acetate copolymer is added in the special solvent, Heating temperature is to 75-95 ℃, after treating that it dissolves fully, add vinylformic acid high-carbon alcohol ester-maleic acid anhydride-propenoic acid ester polymer, vinylformic acid higher alcohols ester polymer, Resins, epoxy and polyethers successively, dissolved 2-3 hour, and obtained liquid pour depressor for crude.
Embodiment:
Example 1: liquid pour depressor for crude prescription of the present invention: high molecular polymer ethylene-vinyl acetate (vinyl acetate 25-40%) 10%, vinylformic acid higher alcohols ester polymer 5%, Resins, epoxy 5%, polyethers 5%; Special solvent is a methyl phenyl ketone 10%, heavy aromatics 60%, butyl glycol ether 5%, more than each material be weight ratio.The liquid pour depressor for crude zero pour that is mixed with is 7.0 ℃, and 20 ℃ of apparent viscosity are 120mPa.s, concrete physical and chemical performance and the pour point depression effect of grand celebration, the Sudan's crude oil seen Table 1 and table 2.
The physical and chemical performance of table 1 liquid pour depressor for crude prescription
| Solvent | Zero pour (℃) | Apparent viscosity (mPa.s) | Flash-point (℃) | Density (g/cm 3) | 24 hours volatility (%) |
| Special solvent | ????7.0 | ????120 | ????67 | ????0.912 | ????2.317 |
| Diesel oil | ????17.0 | ????722 | ????31 | ????0.855 | ????20.528 |
| Dimethylbenzene | ????15.5 | ????486 | ????36 | ????0.872 | ????17.419 |
Table 2 grand celebration, the Sudan's crude oil add the pour point depression effect of liquid pour point depressant
| The crude oil type | Zero pour (℃) | Treatment temp (℃) | Add dosage (g/t) | Processing after coagulation point (℃) | The pour point depression amplitude (℃) |
| Daqing crude oil | ????32.0 | ????60 | ??200 | ????14.5 | ????17.5 |
| The Sudan's crude oil | ????34.0 | ????85 | ??300 | ????19.0 | ????15.0 |
Example 2: liquid pour depressor for crude prescription of the present invention: high molecular polymer ethylene-vinyl acetate (vinyl acetate 25-40%) 12%, Resins, epoxy 10%, polyethers 3%; Special solvent is a heavy aromatics 60%, butyl glycol ether 15%, more than each material be weight ratio.The liquid pour depressor for crude zero pour that is mixed with is 12.5 ℃, and 20 ℃ of apparent viscosity are 186mPa.s, and flash-point is 64.2 ℃, and density is 0.907g/cm
3, volatility was 3.274% in 24 hours, and Liaohe River viscous crude and eastern pour point depression effect of facing the defeated intermediate base crude oil of pipe are seen Table 3.
The pour point depression effect of the defeated intermediate base crude oil of pipe with pour point depressant faced in table 3 Liaohe River viscous crude, east
| The crude oil type | Treatment temp (℃) | Add dosage (g/t) | Zero pour (℃) | The pour point depression amplitude (℃) | Apparent viscosity (mPa.s) | Viscosity break ratio (%) |
| Liaohe River viscous crude | ??0 | ????6.0 | ????20.0 | ????7000 | ????68.0 | |
| ????80 | ??800 | ????-14.0 | ????2240 | |||
| Crude oil is faced in east | ??0 | ????17.0 | ????18.0 | ????941 | ????85.0 | |
| ????60 | ??200 | ????-1.0 | ????141 |
Example 3: liquid pour depressor for crude prescription of the present invention: high molecular polymer ethylene-vinyl acetate (vinyl acetate 25-40%) 8%, vinylformic acid high-carbon alcohol ester-maleic acid anhydride-propenoic acid ester polymer 6%, Resins, epoxy 6%; Special solvent is different Fu Er ketone 6%, heavy aromatics 50%, butyl glycol ether 15%, ethylene glycol dibutyl ether 5%, methyl phenyl ketone 4%, more than each material be weight ratio.Press formula rate, earlier solid-state ethylene-vinyl acetate copolymer is added in the special solvent, Heating temperature to 85 ℃, after treating that it dissolves fully, add vinylformic acid high-carbon alcohol ester-maleic acid anhydride-propenoic acid ester polymer, vinylformic acid higher alcohols ester polymer, Resins, epoxy and polyethers successively, dissolved 2-3 hour, and obtained liquid pour depressor for crude.The liquid pour depressor for crude zero pour that is mixed with is 5.5 ℃, and 20 ℃ of apparent viscosity are 81mPa.s, and flash-point is 66.2 ℃, and density is 0.909g/cm
3, volatility was 2.871% in 24 hours.Pour point depression effect to grand celebration, the Sudan's crude oil sees Table 4.
Table 4 grand celebration, the Sudan's crude oil add the pour point depression effect of liquid pour point depressant
| The crude oil type | Zero pour (℃) | Treatment temp (℃) | Add dosage (g/t) | Processing after coagulation point (℃) | The pour point depression amplitude (℃) |
| Daqing crude oil | ????32.0 | ????65 | ??100 | ????18.5 | ????13.5 |
| ??200 | ????15.5 | ????16.5 | |||
| ??300 | ????14.0 | ????18.0 | |||
| The Sudan's crude oil | ????34.0 | ????85 | ??200 | ????19.5 | ????14.5 |
| ??400 | ????18.0 | ????16.0 | |||
| ??600 | ????17.5 | ????16.5 |
As seen, the present invention's liquid pour depressor for crude is applicable to the coagulation and viscosity reducing of general paraffin content and high paraffin content and high colloid, high pitch crude oil, and the coagulation and viscosity reducing effect is obvious especially; This pour-point depressant solubility property is good simultaneously, viscosity is low, flash-point is high, volatility is little, the long term storage performance is good, can satisfy on-the-spot directly injection condition, can avoid a large amount of volatilizations of solvent to cause the on-the-spot accidents such as difficulty and motor damage of injecting, have efficiently, safety, convenience and the easy characteristics of preparation method.
Claims (5)
1. liquid pour depressor for crude that is used for high pour point and viscous crude oil, comprise high molecular polymer and solvent, it is characterized in that by one or more the composite special solvents in ethylene-vinyl acetate copolymer, vinylformic acid high-carbon alcohol ester-maleic anhydride-vinyl acetate polymer, vinylformic acid higher alcohols ester polymer, Resins, epoxy and the multiple high molecular polymer of polyethers and the different Fu Er ketone of organic solvent, tetraline, methyl phenyl ketone, heavy aromatics, butyl glycol ether and the ethylene glycol dibutyl ether by 1: 2-20 is composite.
2. a kind of liquid pour depressor for crude according to claim 1, it is characterized in that each high molecular polymer is by weight: ethylene-vinyl acetate copolymer 50-90%, vinylformic acid high-carbon alcohol ester-maleic anhydride-vinyl acetate polymer 0-10%, vinylformic acid higher alcohols ester polymer 5-15%, Resins, epoxy 0-25%, polyethers 0-25%.
3. a kind of liquid pour depressor for crude according to claim 1 and 2, it is characterized in that high molecular polymer ethylene-vinyl acetate molecular weight wherein is the multipolymer of 8000-40000, vinylformic acid high-carbon alcohol ester-maleic anhydride-vinyl acetate polymer molecular weight is 5000-100000, vinylformic acid higher alcohols ester polymer molecular weight is 10000-150000, molecular weight of epoxy resin is 3000-20000, and the pfpe molecule amount is 2000-30000.
4. a kind of liquid pour depressor for crude according to claim 1 and 2 is characterized in that vinyl acetate content is 25-40% in the ethylene-vinyl acetate; Vinylformic acid high-carbon alcohol ester-maleic anhydride-vinyl acetate polymer is C
16-24The copolymerization of ester and maleic anhydride, vinyl acetate, wherein maleic anhydride and vinyl acetate content are 5-15% and 2-10%, vinylformic acid higher alcohols ester polymer is C
16-24The homopolymer of alcohol and acroleic acid esterification thing.
5. the compound method of a liquid pour depressor for crude, it is characterized in that by formula rate earlier with one or more mixing in different Fu Er ketone, tetraline, methyl phenyl ketone, heavy aromatics, butyl glycol ether and the ethylene glycol dibutyl ether, again solid-state ethylene-vinyl acetate copolymer is added, be heated to 75-95 ℃, after treating that it dissolves fully, add vinylformic acid high-carbon alcohol ester-maleic acid anhydride-propenoic acid ester polymer, vinylformic acid higher alcohols ester polymer, Resins, epoxy and polyethers successively, dissolved 2-3 hour.
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| CNB001358766A CN1141372C (en) | 2000-12-22 | 2000-12-22 | Liquid pour depressor for crude and its preparing process |
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| Application Number | Priority Date | Filing Date | Title |
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| CNB001358766A CN1141372C (en) | 2000-12-22 | 2000-12-22 | Liquid pour depressor for crude and its preparing process |
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| CN1360016A true CN1360016A (en) | 2002-07-24 |
| CN1141372C CN1141372C (en) | 2004-03-10 |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101386659B (en) * | 2008-11-05 | 2010-09-15 | 中国海洋石油总公司 | Method for preparing oil soluble crude oil improved flowable agent |
| CN101712796B (en) * | 2008-10-08 | 2011-10-05 | 中国石油天然气集团公司 | Reaction type crude oil flow modifying agent containing isocyanate organic macromolecule |
| CN101168701B (en) * | 2006-10-27 | 2013-02-13 | 切夫里昂奥罗尼特有限责任公司 | A lubricating oil additive composition and method of making the same |
| CN104327213A (en) * | 2014-10-15 | 2015-02-04 | 山东大学 | High wax thickened oil nanocomposite pour-point depressant and preparation method thereof |
| CN106047329A (en) * | 2016-06-06 | 2016-10-26 | 中国石油化工股份有限公司 | High-temperature-resistant pour-point depressant and preparation method thereof |
| CN106678548A (en) * | 2016-11-22 | 2017-05-17 | 雷笑天 | Preparation method of viscosity reducer for ultra-viscous oil pipeline transportation |
| CN108084982A (en) * | 2016-11-21 | 2018-05-29 | 中国科学院化学研究所 | Nano-viscosity reduction pour-point depressant stable emulsion and its preparation method and application |
| CN111635792A (en) * | 2020-05-27 | 2020-09-08 | 上海中太行之光能源有限公司 | Environment-friendly antifreeze agent for diesel oil and preparation method thereof |
| CN111826145A (en) * | 2020-07-27 | 2020-10-27 | 北京贝斯特佳科技有限公司 | Petroleum wax precipitation regulating and controlling agent and using method and application thereof |
| CN114057763A (en) * | 2020-08-04 | 2022-02-18 | 中国石油化工股份有限公司 | Spiro compound for reducing viscosity and pour point of crude oil, crude oil viscosity reducing pour point depressant and preparation method of spiro compound |
| CN115746811A (en) * | 2022-11-17 | 2023-03-07 | 中国石油天然气集团有限公司 | Wax-proof pour point depressant for shale oil reservoir and preparation method thereof |
-
2000
- 2000-12-22 CN CNB001358766A patent/CN1141372C/en not_active Expired - Lifetime
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101168701B (en) * | 2006-10-27 | 2013-02-13 | 切夫里昂奥罗尼特有限责任公司 | A lubricating oil additive composition and method of making the same |
| CN101712796B (en) * | 2008-10-08 | 2011-10-05 | 中国石油天然气集团公司 | Reaction type crude oil flow modifying agent containing isocyanate organic macromolecule |
| CN101386659B (en) * | 2008-11-05 | 2010-09-15 | 中国海洋石油总公司 | Method for preparing oil soluble crude oil improved flowable agent |
| CN104327213A (en) * | 2014-10-15 | 2015-02-04 | 山东大学 | High wax thickened oil nanocomposite pour-point depressant and preparation method thereof |
| CN106047329A (en) * | 2016-06-06 | 2016-10-26 | 中国石油化工股份有限公司 | High-temperature-resistant pour-point depressant and preparation method thereof |
| CN106047329B (en) * | 2016-06-06 | 2020-03-06 | 中国石油化工股份有限公司 | High-temperature-resistant pour point depressant and preparation method thereof |
| CN108084982A (en) * | 2016-11-21 | 2018-05-29 | 中国科学院化学研究所 | Nano-viscosity reduction pour-point depressant stable emulsion and its preparation method and application |
| CN106678548A (en) * | 2016-11-22 | 2017-05-17 | 雷笑天 | Preparation method of viscosity reducer for ultra-viscous oil pipeline transportation |
| CN111635792A (en) * | 2020-05-27 | 2020-09-08 | 上海中太行之光能源有限公司 | Environment-friendly antifreeze agent for diesel oil and preparation method thereof |
| CN111826145A (en) * | 2020-07-27 | 2020-10-27 | 北京贝斯特佳科技有限公司 | Petroleum wax precipitation regulating and controlling agent and using method and application thereof |
| CN111826145B (en) * | 2020-07-27 | 2021-03-19 | 北京贝斯特佳科技有限公司 | Petroleum wax precipitation regulating and controlling agent and using method and application thereof |
| CN114057763A (en) * | 2020-08-04 | 2022-02-18 | 中国石油化工股份有限公司 | Spiro compound for reducing viscosity and pour point of crude oil, crude oil viscosity reducing pour point depressant and preparation method of spiro compound |
| CN114057763B (en) * | 2020-08-04 | 2023-07-07 | 中国石油化工股份有限公司 | Spiro compound for reducing viscosity and pour point of crude oil, crude oil viscosity and pour point reducer and preparation method thereof |
| CN115746811A (en) * | 2022-11-17 | 2023-03-07 | 中国石油天然气集团有限公司 | Wax-proof pour point depressant for shale oil reservoir and preparation method thereof |
| CN115746811B (en) * | 2022-11-17 | 2024-03-29 | 中国石油天然气集团有限公司 | Wax-proof pour point depressant for shale oil reservoir and preparation method thereof |
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| CN1141372C (en) | 2004-03-10 |
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