聚合物纳米组装微泡沫钻井液体系及其性能评价

Polymer nano-assembled micro-foam drilling fluid system and its performance evaluation

姚金星 万里平 高攀明 刘振东 陈永斌

YAO Jinxing WAN Liping GAO Panming LIU Zhendong CHEN Yongbin

西南石油大学油气藏地质及开发工程国家重点实验室 延长油田股份有限公司

State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, Sichuan, China Yanchang Oilfield Co. Ltd., Yan'an 716000, Shaanxi, China

在高温、高含盐井下作业环境下，微泡沫钻井液体系性能极不稳定，为此，从优化泡沫分子构成的思路出发，设计出的微泡沫分子结构由2部分组成：内部结构为气核，外部结构为由连续相表面活性剂、聚合物处理剂、纳米材料（SiO₂）组成的薄膜体系，称此种设计为聚合物纳米组装核-壳结构。微泡沫钻井液体系配方：水+0.4%AOS+0.3%瓜尔胶+ (0.12%~0.18%)纳米SiO₂。通过电子显微镜对该微泡沫钻井液体系进行了微观形态评价，结果表明该微泡沫钻井液体系性能比较稳定；当温度处于140 ℃以上时，在该微泡沫钻井液体系中加入质量分数为4%~8%KCl溶液或0.4%~0.8%CaCl₂溶液，该微泡沫钻井液体系仍具有良好的发泡能力，说明聚合物纳米组装核-壳结构下的微泡沫钻井液体系耐温耐盐性能良好。该设计对提高微泡沫钻井液体系性能具有重要意义。

The properties of microfoam drilling fluid are quite unstably in the downhole environment of high temperature and high salt content. To solve this problem, a new type of microfoam drilling fluid was designed in this paper based on the idea of optimizing the molecular compositions of foam. It structurally consists of two parts, i.e., internal structure and external structure. The internal structure is a gas nucleus and the external structure is a film system which is composed of continuous phase surfactant, polymer processing agent and nanomaterial (SiO). Therefore, this design is named as the nucleus-shell structure of polymer nanometer assembly. The formula of microfoam drilling fluid is water + 0.4% AOS + 0.3% guar + (0.12%-0.18%) nano-SiO. And its microscopic properties were evaluated by means of electron microscope. It is indicated the performance of this microfoam system is stable. When the temperature is above 140 ℃, its foaming capacity is still good if it is added with 4%-8% KCl solution and 0.4%-0.8% CaCl solution. It is demonstrated that the microfoam drilling fluid system with the nucleus-shell structure of polymer nanometer assembly is well resistant to high temperature and high salt content. To sum up, this design is of great significance to improving the performance of microfoam drilling fluid systems.

10.13639/j.odpt.2018.05.008