Diagnóstico da qualidade dos efluentes de uma planta de tratamento de esgotos sanitários e propostas para produção de água industrial

Abstract

The New Legal Framework for Sanitation (Law No. 14.026/2020) sets goals to incentivize reclaimed water production, promoting a cultural shift in water reuse. This work evaluates the quality of raw sewage and treated effluents from a wastewater treatment plant (WWTP) (case study) located in Campinas (São Paulo, Brazil) based on the effluent quality index (EQI). It proposes routes for the complementary effluent treatment to enable industrial water production. The EQI estimation followed the methodology proposed by Kothari et al. (2021). The final EQI indicated that the treatment plant produced class A reclaimed water for most of the analyzed period, except in April 2022 (class B), following the classification standards of SVDS/SMS No. 09/2014 (Campinas/SP). The addition of technologies such as reverse osmosis, nanofiltration, and an integrated system of electrolysis─microfiltration─ion exchange was proposed for the advanced treatment of the effluent produced by the WWTP. Reusing sanitary effluents from WWTPs instead of capturing water from existing sources can be an environmentally and economically attractive strategy. It is noteworthy that selecting the route for the final polishing of the treated sewage requires careful analysis to meet the industry's specific needs. In summary, this study highlights the potential use of the EQI to categorize the effluents from the WWTP and its application in an additional treatment chain, aiming to produce industrial water to meet local industry demands.