Gradient Clogging in Depth Filtration

TL;DR

This paper studies the clogging process in depth filtration, revealing a power law distribution of trapped particles and the conditions under which non-trivial permeability behavior occurs in highly anisotropic systems.

Contribution

It introduces a detailed analysis of gradient clogging in depth filtration, highlighting the scaling laws and conditions for non-trivial permeability behavior.

Findings

Clogging follows a power law distribution of trapped particles.

Permeability behavior depends on extreme anisotropic geometry.

System length scales with the logarithm of width for non-pathological clogging.

Abstract

We investigate clogging in depth filtration, in which a dirty fluid is ``cleaned'' by the trapping of dirt particles within the pore space during flow through a porous medium. This leads to a gradient percolation process which exhibits a power law distribution for the density of trapped particles at downstream distance x from the input. To achieve a non-pathological clogging (percolation) threshold, the system length L should scale no faster than a power of ln w, where w is the width. Non-trivial behavior for the permeability arises only in this extreme anisotropic geometry.