Influence of organic matter and carbonate on the secondary urban effluents disinfection by UV/H2O2

Abstract

The main objective of this research was to study the influence of organic matter and carbonate on UV/H2O2 disinfection, and also to start up the UV/H2O2 reactor to conduct disinfection experiments and to analyze the amount of bacteria (total coliforms and E. coli) during the treatment. The analyzes were carried out with samples from the secondary effluent treatment plant of Faculdade de Tecnologia da Unicamp, the Águas da Serra sewage treatment plant in the city of Limeira and with pure water. The experiments consisted in the treatment of secondary effluent samples ana verify the performance to disinfect analising bacterias in four different times. The relation between the organic matter of the effluent and the disinfection process was studied making a relationship between the bactaria inactivatin and the COD of the effluent. The start up of the UV/H2O2 reactor was positive and allowed the accomplishment of disinfection experiments and later the analysis of concentration of bacteria. For samples from the Águas da Serra effluent, which presented COD of 79 mg/l, the disinfection was extremely efficient with different concentrations of peroxide and there was no indication of the presence of coliforms from the first 10 minutes of treatment.