为了研究CO2驱采出液的性质变化规律，利用CO2原油混相装置在模拟地层条件下对长庆原油进行超临界CO2（scCO2）混相处理。分别使用流变仪、电导率仪和显微镜研究了混相处理前后原油及其乳状液的黏度、乳状液的稳定性及油水界面膜形貌。实验结果表明，经scCO2混相处理后长庆原油的饱和分含量减少，而芳香分和胶质、沥青质含量相对升高；scCO2混相处理后长庆原油及其乳状液黏度均有所升高；scCO2处理后的长庆原油胶体体系稳定性被破坏，导致沥青质析出并吸附于油水界面，使得界面膜厚度增大、强度提高，乳状液稳定性增强。上述研究对于CO2驱油技术在长庆油田的应用推广具有重要意义。%In order to investigate the properties of carbon dioxide flooding produced fluid, a self-developed high-pressure CO2-crude mixing container was used to mix up supercritical CO2 (scCO2 ) and Changqing crude oil in miscible flooding under reservoir condition. After scCO2 mixing process, the viscosity of crude oil and its emulsion, the stability of the emul-sion and the morphology of the interfacial film is studied by rheological measurement, con-ductivity meter and microscopic observation. The experimental results show that the content of saturates in Changqing crude oil decreased,and the fractions of resins,asphaltenes and ar-omatics relatively increased through the treatment. The viscosity of Changqing crude oil and its emulsion increased after scCO2 treating. And because the stability of colloidal system is damaged after treated, the asphaltenes which will enhance the strength of the interfacial film dissolve out of the oil and absorb the water/oil interface,, thus the stability of the emulsion is strengthened. This research has guiding significance to the application of CO2 flooding tech-nology in Changqing Oilfield.
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