Two-site colloid transport with reversible and irreversible attachment: Analytical solutions

Analytical solutions for colloid transport in water saturated, one-dimensional, homogeneous porous media, under fully developed uniform flow are presented. The colloids can be either suspended in the aqueous phase or attached reversibly and/or irreversibly onto the solid matrix. Both attachment rates are assumed linear, and any possible blocking or ripening effects are neglected. The colloids can be either of neutral density or denser than the water. For dense colloids, gravity effects are accounted for. Gravity may enhance or hinder the migration of dense colloids, depending on the flow direction. Upstream boundary conditions for both instantaneous and broad-pulse colloid injections are accounted for. The new analytical solutions were used to successfully fit available experimental data.