摘要
聚合物对钻井液的高温流变特性具有重要影响。对比了聚合物种类、加量、剪切时间、盐、造浆黏土等对聚合物溶液高温流变性的影响,并对不同温度下的剪切速率-剪切应力关系进行了流变模型拟合。结果表明,温度升高、剪切时间及盐量增加均导致黏度降低,超过190℃后黏度下降速率加剧;含5%甲酸盐与5%卤盐的样品黏度在降温阶段的黏度恢复率分别为86.8%和2.7%;以宾汉模式对造浆黏土与聚合物混合液进行拟合,220℃时的动切力最高达到5.47 Pa。温度升高使得聚合物溶液由假塑性向牛顿性演变的趋势增强。高于130℃时,长时间剪切导致黏度下降的趋势明显,此时含甲酸盐的聚合物溶液黏度较含卤盐的高,且降温阶段的黏度恢复率也较高。黏土的存在增强了混合液的网间结构,有利于高温下携带岩屑。
Polymer has a significant effect on the high temperature rheology of drilling fluid.The effects of polymer type,addition amount,shear time,salt and clay on the HTHP rheological properties were compared and analyzed,and the relationship of shear rate and shear stress was fitted to different rheological models.The increase of temperature,shear time and salt amount all led to the decrease of viscosity,especially when the temperature exceeded 190℃.In the cooling progress,the viscosity recovery rates of polymer solutions containing 5% HCOONa and 5% NaCl are 86.8% and 2.7%,respectively.Bingham model was used to characterize the mixture of polymer and clays,and the maximum yield point was 5.47 Pa at 220℃.Heating increases the tendency of the polymer solution to change from pseudoplastic to Newtonian.Above 130℃,the tendency of viscosity to decrease is obvious duedue to shear time.Meanwhile,the viscosity of the formate-containing polymer salt solution is higher than that of the chlorinated salt,and the viscosity retention rate of the former in the cooling process is also higher.The presence of clay enhances the structure force of the polymer solution,which is helpful for cuttings transportation at high temperatures.
作者
朱旭明
乌效鸣
郑文龙
迪娜·木拉提
蒋子为
Zhu Xuming;Wu Xiaoming;Zheng Wenlong;Mulati Dina;Jiang Ziwei(Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China;College of Geosciences and Engineering,North China University of Water Resources and Electric Power,Zhengzhou 450046,China)
出处
《地质科技通报》
CAS
CSCD
北大核心
2021年第1期200-208,共9页
Bulletin of Geological Science and Technology
基金
中国地质调查局地质调查项目(12120113017600
DD20160209)。
关键词
钻井液
聚合物
高温流变性
流变模型
黏度
drilling fluid
polymer
high temperature rheology
rheological model
viscosity
