Evaluation of activated carbon in the post-treatment of effluent from the reuse water production station

Abstract

The Reuse Water Production Station (Estação de Produção de Água de Reuso (EPAR CAPIVARI II)) in Campinas, SP, operates with a Membrane Bioreactor (MBR) and has the capactity to produce non-potable reuse water. EPAR is equipped with a pilot station composed by different polishing techniques, which allows assays with multiple barriers to remove the contaminants of interest. Among the polishing techniques installed at EPAR, activated carbon allows an easy application, low cost and the possibility of using various carbon-based materials for its production, including fewer noble ones. Furthermore, when compared to other polishing techniques, such as advanced oxidation processes, the adsorption does not lead to the formation of undesirable by-products, which may induce greater toxicity than the original compound. In previous work, our group screened the EPAR effluent, selecting marker molecules (recalcitrant compounds), such as caffeine, hydrochlorothiazide, saccharin, sucralose, sulfamethoxazole. The objective of this project is to evaluate different adsorbent materials (different activated carbons) and the activated carbon as support material for titanium dioxide particles, aiming at the simultaneous degradation and removal of recalcitrant compounds in the EPAR. The adsorbent materials will be characterized, and laboratory-scale studies will be carried out to elucidate the kinetics, adsorption capacity (isotherms) and adsorption mechanisms. Adsorption will also be evaluated by fixed bed columns designed based on the "Rapid Small Scale Column Test" method. After understanding the adsorption process, experiments will be carried out at the EPAR pilot station and the removal of recalcitrant compounds, antimicrobial activity, estrogenic activity, among other potability parameters will be evaluated to verify the potential for production of reused drinking water. The quantification of recalcitrant compounds will be performed by two-dimensional liquid chromatography - tandem mass spectrometry. (AU)