Impact of microstructure evolution on the difference between geometric and reactive surface areas in natural chalk

摘要: Abstract The coupling between flow and mineral dissolution drives the evolution of many natural engineered systems. Pore surface changes as microstructure evolves but this transient behaviour has traditionally been difficult to model. We combined a reactor network model with experimental, greyscale tomography data establish morphological grounds for differences among geometric, reactive apparent areas in dissolving chalk. This approach allowed us study effects initial geometry macroscopic rate independently. simulations showed that geometric surface, which represents form local transport heterogeneity, increases an imposed field, even when porous structure is chemically homogeneous. Hence, fluid-reaction leads solid channelisation, further results fluid focusing increase area. Fluid decreases area residence time reactant, both contribute over-normalisation reaction rate. In addition, growing merging microchannels, near entrance, macroscopic, fast rocks.