Removal of bacterial indices of pollution during sewage treatment via rotating biological contactor

Two rotating biological contactors (RBC), one bench scale and the other pilot-plant scale, were assessed by using bacterial indices of pollution. The removal efficiency for the pilot RBC was much better than that obtained under laboratory conditions. However, the residual bacterial densities were high enough to represent a potential health hazard. In addition, five different serotypes of enteropathogenic Escherichia coli were isolated from influent and three from effluent samples and 45% of the tested strains were multiple antibiotic resistant.