Electrocoagulation coupled adsorption for anaerobic wastewater post-treatment and reuse purposes.

Water reuse is an indispensable reality in the search for an equilibrium between water resources and water scarcity. The recovery and production of reclaimed water with a guarantee of safety of use requires advanced treatment technologies. This study proposes a conjugated system, composed of electrocoagulation followed by adsorption, for the post-treatment of UASB effluent for reuse purposes. For this purpose, initially the electrocoagulation process (EC) was optimized using response surface methodology. The optimum conditions were for a current density of 29.44 A/m² and pH 6.0, with 44.58% of COD removal and energy consumption of 31.1 kWh per kg of COD removed. The EC effluent was treated by adsorption on a fixed bed column of activated carbon. The conjugated system provided the complete removal of COD and BOD, and significant removals of turbidity (96.5%), phosphorus (97.5%) and total and thermotolerant coliforms. The quality of the final treated water reached parameters for reuse according to EPA. [ABSTRACT FROM AUTHOR]