Determinación de Parámetros de Diseño Y Desinfección con Ozono de un Efluente Municipal.

This paper presents the ozonization evaluation of a secondary effluent. Parameters of reactor design as the value of the initial demand and the kinetic constant of consumption of ozone were determined. The obtained values were 1,6 mg/L and 0,192 min-1 respectively. As well as, ozone effluent disinfection was evaluated to determine the most appropriate operation conditions, to guarantee a sure disinfection and to diminish the environmental impact. The ozonization effect on the quality effluent parameters was evaluated. They were chemistry oxygen demand, the absorbance value to 254 nm, conductivity, pH, biochemical oxygen demand and total suspended solids total. The ozone disinfection was very effective for the inactivation of total and fecal coliforms with a Ct of 5 mg.min/L. On the other hand, the secondary effluent was inoculated with a concentration of 3,4 x 10² UFC/mL of Pseudomonas aeruginosa, to simulate a potential contamination. This pathogen microorganism is frequent in this wastewater and it is resistant to the chloration. The results indicated that a dose of 7 mg/L during 5 minutes is enough. The ozone reduces the environmental impact as disinfection stage, since the high chlorine doses generate residual concentrations higher than 3 mg/L. Which is not desirable and it constitutes an ecological risk for the population health, that is supplied of the water receiver body. A design of the contact system was proposed. The chlorination tank can be used as ozonization reactor with a minimum of modifications. The investment costs can be reduced. This diminishes the investment cost for construction cost reduction. A bubble reactor with double baffles is proposed. It is composed by two mixing chambers. The countercurrent contact among the phases is guaranteed. In the third chamber ozone is not injected. The double baffles are recommended to avoid the short circuit effect. [ABSTRACT FROM AUTHOR]