Transport and clogging of microplastic particles in porous media: Microscale experiments and statistical analysis.

This article focuses on the transport and clogging behavior of microplastics (MPs) in porous media infiltration systems, which are critical for water treatment processes. Using a two-dimensional porous media flow cell (2D-PMFC) based on real gravel profiles, the study statistically analyzed how particle concentration, particle flux, flow velocity, and pore throat geometry influence the probability and mechanisms of MP-induced clogging. The pore throat diameter-to-particle diameter ratio (dt/dp) was identified as the key factor determining clogging probability, with pore throats classified into persistent, occasional, and non-clogging zones; clogging probability in the occasional zone was further affected by particle flux and flow velocity. Two primary clogging mechanisms were observed: independent clogging (including sieving and deposition) and dependent clogging influenced by neighboring pore states. These findings contribute to understanding MP interception in infiltration systems and have implications for optimizing filtration design and mitigating environmental risks.