页岩气调查井复杂地层有机硅聚合物钻井液体系的研制与应用

页岩气调查井通常地质条件复杂，钻探难度大。在对页岩气调查川沐地2井井壁稳定性分析的基础上，优选了有机硅聚合物钻井液体系，并通过正交试验，明确了有机硅改性聚合物、多级配超细碳酸钙、乳化石蜡和硅氟聚合物等主要处理剂的最优加量，形成了基本配方，在室内实验评价中该体系展现了良好的抗钻屑污染能力、抗钙侵能力、抑制性和封堵性。现场应用表明，川沐地2井在采用有机硅聚合物钻井液体系后，井内复杂情况得到明显改善，有效保障了井内安全，并顺利钻进至设计井深，实现了地质目标，钻进效率相比同区域同类型钻井大幅提高。研究成果可为页岩气调查井复杂地层钻探钻井液的选择与应用提供借鉴。

Research and Application of Organosilicon Polymer Drilling Fluid System in Complex Formation of Shale Gas Survey Well

Shale gas survey wells are usually difficult to drill because of complex geological conditions. On the basis of shale gas survey and wellbore stability analysis of Chuanmudi 2 well, the organic silicon polymer drilling fluid system is selected, and through orthogonal test, the optimum dosage of main treatment agents, such as organosilicon modified polymer, multi-grade ultra-fine calcium carbonate, emulsified paraffin and silicon fluoropolymer, is determined, and the basic formula is formed. The system shows good drilling chips contamination resistance, calcium invasion resistance, etc. in the laboratory test evaluation. Inhibitory and plugging properties. Field application shows that after using organosilicon polymer drilling fluid system, complex conditions in well Chuanmudi 2 have been significantly improved, well safety has been effectively guaranteed, and well has been successfully drilled to the designed well depth, realizing geological objectives, and drilling efficiency has been greatly improved compared with the same type of drilling in the same area. The research results can provide reference for selection and application of drilling fluids in complex formation of shale gas survey wells.