Article - Pore-scale hydrodynamics in a bio-clogged porous medium

Experimental three-dimensional particle tracking of flow tracers provides pore-scale hydrodynamics in a progressively bioclogged porous medium. Biofilm growth induces formation of preferential flow paths and stagnation zones, leading to an increase of anomalous transport. The flow evolves from a parallel pore arrangement under unclogged conditions, toward a more serial arrangement with increasing clogging. Exponentially evolving hydrodynamic metrics agree with an exponential bacterial growth phase and are used to parameterize a correlated continuous time random walk model with a stochastic velocity relaxation. The model accurately reproduces transport observations and can be used to resolve transport behavior at intermediate time points within the exponential growth phase considered.