Reactive transport in porous media exhibits multifaceted interactions that are dependent on the matrix and fluid properties, and which ultimately alter these properties. A set of calcareous rock samples with unique mineralogy and varying petrophysical properties are selected for this study. A capillary rise experiment is performed in each sample, first with deionized water and then with a dilute, pH 2, HCl solution. Pre- and post-acid petrophysical properties such as porosity, permeability, pore size distribution, and contact angle are measured for each sample along with the capillary rise profile. The latter is tracked by applying image analysis on video recording. The rock mineralogy significantly affects the acidic fluid intrusion into the rock samples. Calcite dissolution is the main reaction that results in the opening of the pore space. This is more prominent in all the carbonate samples where a higher proportion of calcite minerals is present. A higher capillary rise is consistently observed compared to the neutral fluid along with an increase in porosity and the mean pore size. The contact angle also undergoes changes making the carbonate matrix from oil-wet to neutral-wet. Coupling capillary interactions with fluid reactivity is often neglected in fluid transport phenomena. This study offers new insights into the relative importance of reactivity at the timescale of spontaneous imbibition. This is important in understanding dissolution and precipitation processes during capillary flow.

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pH 对钙质岩石自吸的影响

多孔介质中的反应传输表现出多方面的相互作用，这些相互作用取决于基质和流体特性，并最终改变这些特性。本研究选择了一组具有独特矿物学和不同岩石物理性质的钙质岩石样品。对每个样品进行毛细管上升实验，首先使用去离子水，然后使用稀释的 pH 2 HCl 溶液。测量每个样品的酸前和酸后岩石物理性质，例如孔隙度、渗透率、孔径分布和接触角以及毛细管上升剖面。后者是通过对视频记录应用图像分析来跟踪的。岩石矿物学显着影响酸性流体侵入岩石样品。方解石溶解是导致孔隙空间打开的主要反应。这在方解石矿物比例较高的所有碳酸盐样品中更为突出。与中性流体相比，始终观察到更高的毛细管上升，同时孔隙率和平均孔径也增加。接触角也发生变化，使碳酸盐基质从油湿性变为中性湿性。在流体输送现象中，毛细管相互作用与流体反应性的耦合常常被忽视。这项研究为自发吸入时间尺度上反应的相对重要性提供了新的见解。这对于理解毛细管流动过程中的溶解和沉淀过程非常重要。