Mechanistic basis for particle detachment from granular media

Colloids may become detached from surfaces in environmental systems as a result of chemical and physical conditions. Many researchers reporting on colloidal detachment in natural and model systems have stopped short of mechanistically and quantitatively describing their observations. In this work, a mathematical construct is presented that quantitatively determines the effect of thermodynamics and hydrodynamics on particle detachment from surfaces in granular media. Using the Buckingham pi theorem, a mathematical model is structured based on governing dimensionless groupings. Determining dimensionless numbers elucidates conditions conducive for detachment in engineered and natural porous media. Published detachment data are compared to the mathematical model developed herein and provide support for its utility. Extensions of this technique have utility in many applications where fluid interaction with particulate-laden porous media is encountered.