荧光示踪微球研制及示踪性能

Preparation and tracing performance of fluorescent tracer microspheres

为满足矿场采出液聚合物微球质量浓度检测技术需求,提高对聚合物微球在储层内运移规律的认识,利用荧光分光光度计、高压汞灯紫外光光反应器、全自动酶标仪和荧光显微镜等仪器分析了荧光碳点性能和荧光示踪微球性能。结果表明:荧光碳点具有良好光照耐受性、pH适应性和生物安全性;以种子二次聚合法将荧光碳点与聚合物微球相结合制备荧光示踪微球,可以避免采出液的背底荧光;以采出液的荧光强度峰值计算采出液微球质量浓度并及时调整调驱方案;荧光示踪微球的聚并现象可提高采收率;将荧光碳点与聚合物微球复合注入地层可提高荧光碳点的热稳定性;普通微球和荧光示踪微球均具有较好的注入性能,封堵性能差异不大。研究成果为渤海油田实现大规模聚合物微球的化学调驱提供了有力的技术支持。

In order to meet the technical requirements of mass concentration detections of polymer microspheres in field produced fluid and enhance the understanding of the migration law of polymer microspheres in the reservoir, the performances of fluorescent carbon dots and fluorescent tracer microspheres are analyzed by means of fluorescence spectrophotometer, high-pressure mercury lamp ultraviolet photoreactor, automatic microplate reader and fluorescent microscope. The results show that fluorescent carbon dots have good light tolerance, pH adaptability and biosafety. The fluorescent tracer microspheres are prepared by combination of fluorescent carbon dots and polymer microspheres by secondary seed polymerization, which can avoid back-bottom fluorescence of produced solution. The mass concentration of microspheres are calculated by the peak fluorescent intensity of produced fluid and profile-control displacement scheme is adjusted in time.Coalescence phenomenon of fluorescent tracer microspheres can enhance recovery.Thermal stability of fluorescent carbon dots can be improved by composite injection of fluorescent carbon dots and polymer microspheres into formation.Common microspheres and fluorescent tracer microspheres have better injection performances, and the sealing performance is not different. The research results provide technical support for chemical profile-control flooding of large-scale polymer microspheres with the help of the fluorescent tracer microspheres in Bohai Oilfield.