关键词: 蒙脱石, 微观结构, 钻井液, 温度, 无机盐

Abstract: The osmosical hydration of montmorillonite has been considered to be one of the most important factors of oil reservoir damages and bit balling. The effects of temperature, inogranic salts (NaCl, KCl, CaCl₂ ) and additive CMC (they are often applied to drilling muds) on the micro structure of montmorillonite were studied. The detection methods of the small angle X-ray diffusion, the micro angle X-ray diffusion and of the Pons' statistic model and fractal theory were used, the results showed that the particle's thickness had increased and developed into 80 crystal sheets from a few crystal sheets of the original. At the same time,the interior order of particle aggregates had also increased.This had made the montmorillonite suspension passing from a gel state to an hydrated solid.The high temperature brought about the particles becoming irreversiblely smaller in the direction vertical to the crystal sheet.

Key words: montmorillonite, microstructure, drilling fluid, temperature, inorganic salt