Large-Scale Experiments in Microbially Induced Calcite Precipitation (MICP): Reactive Transport Model Development and Application

Abstract:

We develop reactive transport model simulation for a large-scale experiment involving MICP in context of geotechnical manipulation of soil strength. A cylindrical tub was loaded with natural unconsolidated sandy porous media, saturated, and then augmented with a suspension of the ureolytic bacterium Sporosarcina Pasteurii. To stimulate MICP, the tank was subjected to cyclic injection of reagent solutions among three wells positioned in the tank to create nonuniform flow patterns. COMSOL/iCP and PHT3D were used separately to model the reactive transport processes including transient nonuniform flow, ureolysis, calcite precipitation, and microbial dynamics. The effect of porosity reduction due to calcite precipitation on hydraulic properties of the porous media is coupled with flow and reactive transport model. We study this coupling in both modeling platforms.