Influence of operating conditions on extracellular polymeric substances and surface properties of sludge flocs

► Effect of operating conditions on exopolymers and sludge properties was performed. ► Two modes of reactor operation, S-mode and B-mode, were investigated. ► Polysaccharides (PS) and proteins (PN) were the main components of exopolymers. ► LB-EPS content was related to operation modes and sludge-retention time (SRT). ► PS and PN in LB-EPS and TB-EPS were both dependent of operation modes and SRT.