Influence of polymer charge on the compressive yield stress of silica aggregated with adsorbed cationic polymers

Abstract

Flocs were produced by adding three cationic polymers (10% charge density, 3.0 × 105 g/mol molecular weight; 40% charge density, 1.1 × 105 g/mol molecular weight; and 100% charge density, 1.2 × 105 g/mol molecular weight) to 90 nm diameter silica particles. The compressive yield stresses of the consolidated sediment beds from settled and centrifuged flocs were determined using the volume fraction profile method. The polymer charge density plays an important role in influencing the compressive yield stresses of sediment beds. The compressive yield stresses of sediment beds from flocs induced by the 10% charged polymer were observed to increase with an increase in polymer dose, initial solids ..