页岩气井油基钻屑氟碳除油剂的研制及作用机理

Research on fluorocarbon cleaning agent and action mechanism of oil-based drilling cuttings in shale gas well

谢水祥 任雯 司庆柯 张明栋 刘光全 邵志国 夏宇 李宗锟

XIE Shuixiang REN Wen SI Qingke ZHANG Mingdong LIU Guangquan SHAO Zhiguo XIA Yu LI Zongkun

石油石化污染物控制与处理国家重点实验室 中国石油集团安全环保技术研究院有限公司 长庆实业集团陕西长实建设工程有限公司 长江大学石油工程学院

State Key Laboratory of Petroleum Pollution Control, Beijing 102206, China CNPC Research Institute of Safety and Environmental Technology Co., Ltd., Beijing 102206, China Changqing Industrial Group Shaanxi Changshi Construction Engineering Co., LTD., Xi’an 710021, Shaanxi, China School of Petroleum Engineering, Yangtze University, Wuhan 430100, Hubei, China

页岩气开发钻井过程中会产生油基钻屑，化学热洗法是处理油基钻屑的主要技术之一，但应用过程中存在现有除油剂除油效率低、新药剂开发缺少理论指导等不足。采用接触角测量仪、X射线衍射仪等分析手段，研究了油基钻屑表面油类吸附机理，合成了新型“疏水疏油”氟碳除油剂，并对合成产物的分子结构进行了红外光谱和核磁共振光谱分析表征。研究结果表明，不同油类对油基钻屑润湿性影响不同，柴油更易于在黏土矿物含量低的油基钻屑表面铺展；不同油类在干净钻屑表面吸附量0.1~0.2 g/g，且2~3 h即可达吸附平衡；吸附的有机物主要为C₁₆~C₂₀正构和异构烷烃，占有机物总量的56.5%；油基钻屑经“疏水疏油”氟碳除油剂洗油处理后，含油率由处理前的7%~10%降低至0.15%~0.97%，低于现场含油钻屑除油剂SDS的 2.08%~2.79%。通过接触角测定和分子模拟等方法研究了氟碳除油剂改变油相接触角、降低油基钻屑的油水界面张力和改变其润湿性等作用机理，为油基钻屑除油剂的开发及应用提供理论支持。

Oil-based drilling cuttings will be produced during the drilling process of shale gas development. Thermochemical cleaning is one of the main technologies to treat oil-based drilling cuttings. However, there are shortcomings in the application process, such as low oil removal efficiency of existing oil removal agents and lack of theoretical guidance for the development of new drugs. Using contact angle measuring instrument, X-ray diffractometer and other analytical methods, the adsorption mechanism of oil on the surface of oil-based drilling cuttings was studied, and a new “hydrophobic and oleophobic” fluorocarbon oil cleaning agent was synthesized, and the molecular structure of the synthesized product was analyzed. Infrared spectroscopy and nuclear magnetic resonance spectroscopy and other analytical characterization. The research results show that different oils have different effects on the wettability of oil-based drilling cuttings. Diesel oil is easier to spread on the surface of oil-based cuttings with low clay mineral content. Different oils have a large adsorption capacity 0.1-0.2 g/g on the surface of clean drill cuttings, and the adsorption equilibrium can be reached within 2-3 hours. The adsorbed organics were mainly C-C normal and isoparaffins, accounting for 56.5% of the total organics. After oil-based drilling cuttings are washed with "hydrophobic and oleophobic" fluorocarbon oil washing agent, the oil content is reduced from 7%~10% before treatment to 0.15%-0.97%. And it is lower than the SDS 2.08%-2.79% of the oil-bearing drilling cuttings degreaser on site. And the mechanism of "hydrophobic and oleophobic" degreaser changing the oil phase contact angle, reducing the oil-water interfacial tension of oil-based drilling cuttings and changing its wettability is studied, which can provide information for the development and application of oil cleaning agent for oil-based drilling cuttings.

10.13639/j.odpt.2022.05.006