Author(s)

Yaneth Bustos, Mabel Vaca, Raymundo López, Erick Bandala, Luis Torres, Neftalí Rojas-Valencia

Departamento de Energía, Ciencias Básicas e Ingeniería, Universidad Autónoma Metropolitana, Azcapotzalco, México.
Departamento de Ingeniería Civil y Ambiental, Universidad de las Américas, Puebla. Sta. Catarina Mártir, Cholula, México.
Unidad Profesional Interdisciplinaria de Biotecnología, Instituto Politécnico Nacional, México D. F., México.
Universidad Nacional Autónoma de México, Instituto de Ingeniería, Coordinación de Ingeniería Ambiental, México D. F., México.

UV radiation and ozonation were investigated as disinfection alternatives for the wastewater treatment plant. The inactivation of total and fecal coliforms using ozone and ultraviolet radiation as separate treatments was evaluated. Different ozone concentrations (3 to 40 mg O₃/L) were applied and UV fluencies ranging from 8.5 to 12 mJ/cm² at different pH values (from 5 to 9) were tested. Best results were obtained for ozone doses near 20 mg/min with removals of 72% and 78% of fecal and total coliforms, respectively. The ozone also was capable of oxidizing organic matter in the effluent measured as COD (the highest removal obtained was 36% for 20 mg O₃/min). Maximum bacterial resistance was observed at pH 7 in both cases. The UV light offered a high bacterial inactivation (over 80%) and the lowest bacterial inactivation was observed at pH 7. Finally, we obtained the electric energy per order (E_EO, kWh/m³/order), defined as the electric energy (kW-h) required to degrade a contaminant by one order of magnitude in a unit volume of contaminated water, being noteworthy that E_EO values for the UV process resulted were lower than those determined for the process with ozone in all the water flow tested.

Disinfection; Ozone Treatment; UV Treatment; Wastewater

Y. Bustos, M. Vaca, R. López, E. Bandala, L. Torres and N. Rojas-Valencia, "Disinfection of Primary Municipal Wastewater Effluents Using Continuous UV and Ozone Treatment," Journal of Water Resource and Protection, Vol. 6 No. 1, 2014, pp. 16-21. doi: 10.4236/jwarp.2014.61003.