高性能CaCl_2/聚合物水基钻井液的室内研究

在自制新型烯类聚合单体的基础上,合成出一种新型配套的、抗Ca Cl2至饱和的强抗钙聚合物,初步形成了2种Ca Cl2/聚合物水基钻井液的基本配方:水+1.5%(3.0%)凹凸棒石+0.3%(0.2%)XC+5%KCl+40%(60%)无水Ca Cl2+2%强抗钙聚合物,强抗钙聚合物与Ca Cl2能形成良好的协同效应,是体系的核心。综合性能评价结果表明,Ca Cl2/聚合物钻井液的抑制性能和润滑性能尤为突出,在120℃滚动老化16 h后,一次、二次回收率均为100%,抑制能力超强;体系的黏附系数为0.001 69,润滑系数最低为0.038,达到油基钻井液水平;强抗钙聚合物对凹凸棒石具有较强的吸附和分散能力,可以形成薄而致密的滤饼,显著提高体系降滤失能力;可以用聚合醇或聚电解质作封堵剂;含60%Ca Cl2的配方抗温达120℃。可以得出,该体系具有满足复杂地层钻井要求的潜力,与油基钻井液性能相仿,并且成本低,无污染,满足排放标准,维护简单,具有良好的应用前景。

Study on High Performance CaCl2/Polymer Water Base Drilling Fluid

Two water base drilling fluids were formulated with CaCl2 and polymers highly resistant to calcium contamination. Compared with other water drilling fluids, the CaCl2/polymer drilling fluids had better performance;the inhibitive capacity and lubricity of the drilling fluids were greatly improved. After hot rolling 16 hours at 120℃, the first percent recovery and secondary percent recovery of shale samples were both 100%. Friction coefficient of the drilling fluid was as low as 0.038, almost the same as that of oil base drilling fluid. This drilling fluid was cost effective, pollution-free, and easy to use.