原油电场改性降黏率与能量密度的关系及其机理

中国石油大学(北京)机械与储运工程学院 • 油气管道输送安全国家工程研究中心 • 石油工程教育部重点实验室 • 城市油气输配技术北京市重点实验室

含蜡原油;电场处理;电流变效应;降黏率;流动保障

Study on the relationship between viscosity reduction and energy density in electric treatment of crude oil and related mechanisms
ZHANG Chaoyue,LI Hongying,WANG Yu,LI Qibing,KANG Jiabao,LAN Xin,XIE Yiwei,ZHANG Jinjun

College of Mechanical and Transportation Engineering, China University of Petroleum (Beijing)//National Engineering Research Center for Pipeline Safety//MOE Key Laboratory of Petroleum Engineering//Beijing Key Laboratory of Urban Oil and Gas Distribution Technology

waxy crude oil, electric treatment, electrorheological effect, viscosity reduction, flow assurance

DOI: 10.6047/j.issn.1000-8241.2025.01.007

备注

【目的】电场改性是一种新兴的含蜡原油低温流动性改善方法。针对酒东原油的已有研究发现,电场输入能量密度是含蜡原油电场降黏效果的外部决定性因素,且当输入能量足够大时,电场处理可使油样达到该温度下的最大降黏率。为指导原油电场改性的工业应用,需进一步验证该研究成果对其他原油的适用性。【方法】针对长庆原油与大庆原油,通过探究不同电场处理条件(场强0~3kV/mm、处理时间0~1200s、处理量1.0~2.5mL)对原油电场降黏效果影响,研究并验证输入能量与降黏率的关系。【结果】发现并定义了最大降黏率能量密度阈值,即原油达到最大电场降黏率所需输入的最小能量密度。明确了处理温度(累计析蜡量)对最大降黏率与相应能量密度阈值的影响。随着处理温度降低,最大降黏率增大,相应的能量密度阈值减小。结合显微观察与带电胶粒运移、吸附机理,分析其内在原因:在较低处理温度下,有更多的蜡晶颗粒受到了胶质、沥青质作用;更多、更大的蜡晶导致电场作用下蜡晶表面出现更多电荷,从而促进胶质与沥青质在介电泳作用下向蜡晶表面运移,并积聚在蜡晶表面,因此最大降黏率增大且所需能量密度阈值更小。【结论】研究结果深化了相关原油电流变效应机理的认识,能量密度阈值的发现为处理器电源参数确定与优化提供了重要参考。(图 12表2,参[23]
[Objective] Electric treatment is a new method to improve the cold flowability of waxy crude oil. Previous studies on Jiudong crude oil have identified the input energy density of the electric field as a key factor in reducing the viscosity of waxy crude oil. When the input energy is sufficiently high, the electric treatment can achieve the maximum viscosity reduction at a given temperature. To guide the industrial application of electric treatment for crude oil, further verification of this conclusion’s applicability to other crude oils is essential. [Methods] The relationship between input energy and viscosity reduction rate for Changqing crude oil and Daqing crude oil was investigated by examining the influence of varying electric field treatment conditions (field intensity: 0−3 kV/mm, treatment time: 0−1,200 s, treatment capacity: 1.0−2.5 mL) on the viscosity reduction effect. [Results] The energy density threshold for the maximum viscosity reduction was defined for the first time, indicating the minimum energy density required for crude oil to achieve the maximum viscosity reduction through electric field treatment. The impact of treatment temperature (cumulative wax precipitation) on the maximum viscosity reduction and the corresponding energy density threshold was assessed. As treatment temperature decreased, the maximum viscosity reduction increased, while the corresponding energy density threshold decreased. The intrinsic reasons were analyzed through microscopic examination, focusing on the mechanisms of migration and adsorption of charged colloidal particles. At lower treatment temperatures, more wax particles were influenced by resin and asphaltene. The presence of more and larger wax particles increased surface charges under the electric field, promoting the migration of resin and asphaltene to the wax particle surface via dielectrophoresis, resulting in greater accumulation. Consequently, the maximum viscosity reduction increased, and the energy density threshold required became lower. [Conclusion] The research results facilitate the understanding of the mechanism behind the electrorheological effect of crude oil, and the discovery of the energy density threshold offers a valuable reference for determining and optimizing processor power parameters. (12 Figures, 2 Tables, 23 References)
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