LAUSR

Abstract Agglomeration of solid particles in aqueous liquid flows is generally influenced by the appropriate interacting forces. Between hydrophobic particles, these forces are dramatically increased compared to van der Waals forces due to the formation of capillary bridges, caused by nanobubbles located at the particle surface. In this study, both hydrophobic and hydrophilic agglomerates were generated in water with an agglomeration setup based on a stirred tank reactor. Variating the shear rate leads to different agglomeration sizes and provides information about the agglomerate strength. In principle, both stability and size of the hydrophobic agglomerates are larger than the hydrophilic ones. The presence of the nanobubbles is proved by applying atomic force microscopy to the particle surface.