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Updated: Aug 11, 2026
10:56
Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
Flow-Induced Intermittent Transport Shapes Colloid Filtration in Complex Media
Filippo Miele1, Ankur Deep Bordoloi1, Pietro de Anna1
1University of Lausanne, Institute of Earth Sciences, Lausanne 1015, Switzerland.
Physical Review Letters
|August 10, 2026
Summary
Colloidal transport in heterogeneous porous media exhibits intermittent particle movement. A new model links this behavior to deposition and breakthrough curves, improving filtration predictions.
Area of Science:
- Environmental science
- Geology
- Physics
Background:
- Colloidal transport and filtration in porous media are typically modeled using single-collector models.
- These models assume a homogeneous structure, which may not accurately represent real-world conditions.
Purpose of the Study:
- To investigate colloidal transport and filtration in heterogeneous porous media.
- To develop a model that links intermittent colloidal trajectories to macroscopic filtration behavior.
Main Methods:
- Microfluidic experiments
- Particle tracking
- Simulations
- Stochastic continuous-time random walk model
Main Results:
- Colloidal trajectories in heterogeneous porous structures are intermittent, characterized by 'flights' and 'dives' near grain surfaces.
- Attachment events occur during the 'dives' near grain surfaces.
- The proposed model successfully links intermittent behavior to macroscopic deposition profiles and breakthrough curves.
Conclusions:
- Heterogeneity in porous structures significantly impacts colloidal transport dynamics.
- The developed stochastic model provides a more accurate representation of filtration in complex porous media.
- This work enhances the understanding of contaminant transport and filtration processes.
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