【摘要】 稠油乳状液的破乳是油田油水处理的一个重要难题，乳状液稳定性强、破乳困难导致原油脱水成本升高。对稠油成乳机理的分析是采出油破乳研究的基础，针对辽河油田热采稠油包水乳状液产量大、处理难的问题，对稠油性质进行了测试，开展稠油再乳化实验，以研究乳状液形成机理及其影响因素，并结合现场生产实际，分析稠油乳状液产生的原因。结果显示：辽河油田稠油乳状液含水率高达52%,水以小液滴的形式分散在稠油中。稠油含有较高的天然乳化剂成分，是乳状液形成的物质条件。稠油中的固相物质以石英为主，黏土含量较高，且以分散吸附性好的蒙脱石为主，胶质和沥青质组分占比超过24%,酸值高达5.47 mgKOH/g。高温、剪切、超声等外界能量的输入，以及固体微粒、表面活性剂等乳化剂对油水界面膜的稳定机制，是稠油形成乳状液的主要机理。蒸汽吞吐热力采油、复杂管线集输系统的稠油开采工艺，高孔、高渗、高黏土含量的地层条件，以及高酸值、高胶质和沥青质的稠油性质，为热采稠油的乳化提供了能量和物质条件，共同促进了油田现场稠油包水乳状液的大量生成。研究成果为油田后续乳状液破乳提供了实验和理论基础，对原油脱水处理技术具有指示性意义。更多还原

【Abstract】 De-emulsification of heavy oil emulsion is a great challenge to the oilfield production water treatment, which would cost very much due to the strong stability of the emulsion. Analysis of the emulsification mechanism is the fundamental to the further de-emulsification process. For the purpose of the potential treatment of the large amount of produced water-in-oil emulsions in Liaohe oilfield, the heavy oil properties were measured and re-emulsifying tests were conducted to investigate the emulsification mechanism of the heavy oil. The reasons on the heavy oil emulsion formation were also analyzed by considering the field in-situ production practice. Results show that the heavy oil emulsion in Liaohe oilfield has high water ratio up to 52%. The water is dispersed as small droplets in the heavy oil. The heavy oil also possesses high content of natural emulsifying agents based on which the heavy oil emulsion could be formed. The solid particles in the oil are mainly composed by quartz, and also high content of clay particles, most of which is montmorillonite with good dispersion and adsorption properties. The resins and asphaltenes take up to more than 24% in the hydrocarbons. The heavy oil possesses a high acidity of 5.47 mgKOH/g. The emulsifying mechanism of the heavy oil is determined by the external input energy, such as temperature, shearing and ultrasonic energy, and the stable oil-water interface film forms by the adsorption of solid particles and surfactants. The in-situ formed heavy oil emulsion is controlled by three factors of recover and transportation process, including the thermal recovery method and complex pipeline transportation system for the heavy oil, formation properties, including the high porosity, high permeability and high content of clay mineral composition, and heavy oil properties including the high acidity, high content of resins and asphaltenes, which provide favorable energy and substance for the heavy oil emulsification and finally resulting in the formation of large amount of water-in-heavy oil emulsions. The research findings provide experimental and theoretical foundations for subsequent emulsion demulsification in oilfields, offering indicative significance for crude oil dehydration treatment technologies.更多还原