${\text{CO}}_3^{2？}{\text{/HCO}}_3^{？}$对粘土吸附性能影响研究
Study on the Influence of ${\text{CO}}_3^{2？}{\text{/HCO}}_3^{？}$ on the Adsorption Performance of Clay

钻井液发挥作用主要通过处理剂在粘土上的吸附作用，但在钻井过程中常常会遇到${\text{CO}}_3^{2？}{\text{/HCO}}_3^{？}$ 污染的问题，导致处理剂失效，使钻井液体系流变性和滤失性出现严重恶化。本文通过室内实验模拟CO₂侵入粘土基浆的性能，分析${\text{CO}}_3^{2？}{\text{/HCO}}_3^{？}$ 污染对粘土基浆的流变、滤失性能影响规律，从处理剂角度分析${\text{CO}}_3^{2？}{\text{/HCO}}_3^{？}$ 污染机理。研究结果表明：${\text{CO}}_3^{2？}{\text{/HCO}}_3^{？}$ 污染存在临界值，当${\text{CO}}_3^{2？}{\text{/HCO}}_3^{？}$ 浓度达到1564 mg/L时粘土基浆粘度和滤失量出现大幅上升的趋势，且随着污染程度的加重，粘土颗粒逐渐聚集，形成大颗粒、漏失通道增大；对RSTF吸附实验结果表明，污染前RSTF在粘土上吸附平衡量为103.21 mg/L，污染后吸附平衡量大幅减小，吸附等温线Langmuir方程比Freundlich方程能更好地描述RSTF在粘土颗粒上的吸附过程。
Drilling fluids function mainly through the adsorption of the treatment agent on the clay, but ${\text{CO}}_3^{2？}{\text{/HCO}}_3^{？}$ contamination is often encountered during the drilling process, leading to treatment agent failure and severe deterioration of the rheology