Flocculation kinetics and mechanisms of microalgae- and clay-containing suspensions in different microalgal growth phases

•We studied flocculation of microalgae- and clay-containing suspensions.•Investigations were done in different microalgal growth phases.•A two-class flocculation kinetic model and Bayesian calibration were applied.•Effect of organic matter secreted by algae on flocculation kinetics was evaluated.•Distinct flocculation mechanisms were identified in different microalgal growth phases.