Tecnologia de Ponto-de-Uso (POU) para desinfecção de água para consumo humano: reator UV-ozônio

Abstract

In pursuit of universal access to basic sanitation, particularly safe drinking water for human consumption, various technologies have been developed for individual water treatment in small communities, known as point-of-use (POU) technologies. Chlorine, ozone, UV radiation, and solar radiation are well-known disinfection agents, but UV radiation-based technologies have been gaining prominence in research on potable water disinfection. In light of this, the present study developed a UV-O3 reactor on a bench scale for combined disinfection of surface water. The project's development was divided into three stages: the first stage aimed to analyze ozone generation by the UV lamp (254 nm and 185 nm); the second stage aimed to analyze the inactivation efficiency using only UV radiation; the third stage involved combined disinfection using UV radiation and ozone generated by the UV lamp (UV-O3 reactor). The UV-O3 reactor showed greater disinfection efficiency compared to UV radiation individual treatment for the inactivation of total coliforms, E. coli, and aerobic bacteria spores. However, UV radiation disinfection was more efficient in inhibiting photoreactivation and dark recovery for E. coli and total coliforms. The disinfection processes did not result in significant reductions in the physical-chemical characteristics of the water, but the variation in the concentration of DOC (Dissolved Organic Carbon) during the experiment may have interfered with the disinfection efficiency, especially in the UV-O3 treatment. The UV-O3 reactor demonstrated inactivation potential for indicator and resistant microorganisms, but reducing organic content before disinfection could potentially improve system performance.