The reactor was operated at different MLVSS concentrations and HRTs. The settled sludge from the
clarifier was removed from the beaker daily and the desired concentration of MLVSS was maintained
inside the aeration tank manually.A DO level of around 2 mg/ l was maintained inside the aeration
tank throughout the study. The two chosen operating parameters, i.e. MLVSS concentration and HRT
were varied during the course of the study keeping into consideration the generally applied range in
activated sludge process for industrial effluent treatment. The reactor was operated for MLVSS
concentrations of 2500, 3500 and 5000 mg/ land HRT value of 18, 24 and 36, respectively. All the
connections were made with silicon tubes.