Experimental Study on Reservoir Acidification and Application Effect of Interstratified Illite/Smectite Clay
Keywords:Clay Minerals, Acidification Experiment, Application Effect, Oilfield Development.
AbstractThis paper investigates and studies the advantages and disadvantages of existing acidification plans at home and abroad. In view of the high content of clay matrix in the glutenite reservoir, and in accordance with the mix proportion plan of "HF/HBF4+HCl+oxidants/additives”, the author selects different types of chemical reagents and concentrations, and conducts hydrothermal experiments on smectite and illite by different acidification plans. In the light of mass loss and variation in ion concentration, it is determined through preliminary selection and optimal selection that the best acidification plan is "15%HCl +8%HBF4+ 30%H2O2+ 9%NH4 F”. The proposed acidification plan is applied to clay mineral samples purified from the cores and real core samples, and its effect is analyzed in the light of mass loss, permeability changes, variation in ion concentration, and with the aid of Scanning Electron Microscope (SEM). The experiment reveals that over 40% of the mixed clay minerals are corroded in the reaction, the core samples feature significant increase in the number of corrosion holes and fissures and exponential growth in permeability, and the corroded minerals are mainly interstratified illite/smectite (I/S) and illite. The findings demonstrate that the proposed acidification plan has a good effect on interstratified I/S clay.
How to Cite
Xiyu, Q., Xiaofang, D., Zhen, L., Shoupeng, Z., Weiqing, W., & Zhengwei, F. (2017). Experimental Study on Reservoir Acidification and Application Effect of Interstratified Illite/Smectite Clay. Journal of Mines, Metals and Fuels, 65(8), 444–453. https://doi.org/10.18311/jmmf/2017/26983