碳酸盐岩酸化反应机理分析

AN ANALYSIS OF ACIDIZING REACTION MECHANISM OF CARBONATES

为进一步阐明酸液化学添加剂与碳酸盐岩储层开采的关系,文章通过讨论酸岩反应动力学模式,归纳出酸岩扩散与表面反应控制速率方程,并结合实际酸/岩(液/固)反应动力学分析导出无量纲动力学参数的表达式。鉴于酸液是一种电解质浓溶液,文章还从流体动力学和电解质溶液理论的角度,对影响H+扩散传质的各种影响因素作了理论分析,并通过研究边界层的形成和工作液流动状态下的酸/岩反应,提出盐酸与碳酸盐岩的反应主要受H+液相扩散传质和液/固表面反应动力学影响的观点,而H+液相扩散传质速率又取决于工作液在边界层的流动状态。

In order to further demonstrate the relationship between chemical additives in acid fluid and exploitation of carbonate reservoirs, equations of acid/rock diffusion and surface reaction controlling rate are established based on the kinetic models of acid-rock reaction, and expressions of dimensionless kinetic parameters are derived in combination with analysis of the actual acid/rock (liquid/solid) reaction kinetics. Considering that acid fluid is a kind of concentrated electrolytic solution, various factors that influence H+ diffusion mass transfer are also theoretically analyzed on the basis of fluid kinematics and electrolytic solution theories. Based on studying the formation of boundary layer and the acid/rock reactions in the flowing conditions of operating fluids, it is believed that reaction between chlorhydric acid and carbonates are mainly influenced by H+ diffusion mass transfer of liquid phase and fluid/solid surface reaction kinetics, while the rate of H+ diffusion mass transfer of liquid phase is dependent on the flow conditions of the operating fluid in boundary layer.