Model for the hydrodynamic dispersion of agglomerates incorporating thermoresponsive additives

A phenomenological model for the hydrodynamic dispersion of silica agglomerates modifi ed with a thermoresponsive hydrogel (poly- N -isopropylacrylamide, PNIPAM) is presented. The model well describes experimental observations of the dependence of the dispersion behavior on the presence of additives (water and PNIPAM hydrogels) and applied hydrodynamic stress. Most importantly, the thermosensitivity of the dispersion process is captured by characterizing the agglomerate structure and cohesive force at two different temperatures (above and below the hydrogel transition temperature). The transition in dispersion mechanism between rupture-like and erosion-like regimes with system temperature can also be accommodated within the model.