岩石矿物成分对酸岩反应速率影响规律研究

分析酸液与岩石的化学反应速率规律是碳酸盐岩储层酸化改造技术研究的核心问题。岩石矿物成分是酸岩反应速率的重要影响因素。探索岩石中矿物成分对酸岩反应速率的影响规律，既有助于揭示各类矿物之间竞争反应机理，又可以优化各类型碳酸盐岩改造思路。结合X衍射分析与酸岩反应实验，定量测试了不同矿物成分及含量组成下，酸液与岩石的反应速率。研究表明：①碳酸盐岩各类矿物中方解石、白云石与反应速率呈正比，其他矿物与反应速率呈反比；方解石比白云石反应速率更快。②在灰岩中，当白云石含量为0%~15%与15%~40%时，酸岩反应速率随方解石含量增加升高幅度下降51.4%；当其他矿物含量为0%~15%与15%~30%时，酸岩反应速率随方解石含量增加升高幅度下降61%。在白云岩中，当方解石含量为0%~4%与4%~8%时，酸岩反应速率随白云石含量增加升高幅度上升23%；当其他矿物含量为0%~15%与15%~35%时，酸岩反应速率随白云石含量增加升高幅度减小99%。

Reseach on the Influence Law of Rock Mineral Composition on the Reaction Rate of Acid Rock

Analysing the chemical reaction rate law between acid and rock is the core issue in the research of acidification and transformation technology of carbonate reservoirs. The mineral composition of rock is an important influence factor of acid rock reaction rate. Exploring the influence of rock mineral composition on the acid rock reaction rate not only helps to reveal the competitive reaction mechanism between various types of minerals, but also can optimise the reforming ideas of various types of carbonate rocks. Combining X diffraction analysis and acid-rock reaction experiments, the reaction rates between acid and rock under different mineral compositions and content compositions were quantitatively tested. The results are as follows.①Among the various types of carbonate rock minerals, calcite and dolomite are positively proportional to the reaction rate, while other minerals are inversely proportional to the reaction rate; calcite has a faster reaction rate than dolomite. ②In tuff, when the content of dolomite is 0%~15% and 15%~40%, the reaction rate of acid rock decreases by 51.4% with the increase of calcite content. When the content of other minerals is 0%-15% and 15%-30%, the acid rock reaction rate decreases by 61% with the increase of calcite content. In dolomite, the acid rock reaction rate increased by 23% with the increase of dolomite content when the calcite content was 0%~4% versus 4%~8%. When the content of other minerals is 0%~15% and 15%~35%, the acid rock reaction rate decreases by 99% with the increase of dolomite content.