Unbiodegradable soluble COD removal from industrial wastewater by a hybrid moving bed biofilm reactor

In this study, plastics industry wastewater (PIWW) characterized by high total and soluble chemical oxygen demand (tCOD and sCOD, up to ~2200 and ~1500 mg/L, respectively) and remarkable unbiodegradable soluble COD (usCOD, 508±224 mg/L, 31±14% of tCOD) concentrations was treated at laboratory scale using a hybrid moving bed biofilm reactor (MBBR). Interestingly, the MBBR showed average tCOD, sCOD and usCOD removal efficiencies of 26±6, 32±11 and 36±11%, respectively, which were comparable to those achieved by the coagulation/flocculation pre-treatment currently applied at full-scale. Such results encourage the application of MBBR as a cost-effective option for the removal of recalcitrant soluble organics from PIWW and other similar industrial wastewaters.