The kinetics of protein removal by activated sludge

The removal of bovine serum albumin (BSA) by BSA acclimated activated sludge took place in two stages. Removal during stage 1 was attributed to adsorption. The removal of BSA during stage 2 was slower than stage 1. There was never an accumulation of protein degradation products and removal was accompanied by an increase in the metabolic activity of the activated sludge. The removal of BSA per unit biomass during stage 2 was influenced by both the concentration of BSA and the concentration of activated sludge At high concentrations of BSA, removal was preceded by a lag phase. The rate of removal during stage 2 was constant. Within limits the rate of removal of BSA was related to the substrate to biomass () ratio of the system and to the concentration of BSA expressed per unit biomass remaining in equilibrium following stage 1 of BSA removal.