High-strength ethylene glycol wastewater treatment in anaerobic polyvinyl alcohol gel beads based biofilm reactor

In this paper, ethylene glycol wastewater (EGW) treatment was studied by using one anaerobic polyvinyl alcohol (PVA) gel beads based biofilm reactor. Enhanced by PVA-gel beads based biofilm, organic loading rate (OLR) about 11 g COD l^-1 d^-1 was achieved at the end of this study. Black PVA-gel beads with an average settling velocity 322 m h^-1 (9 cm s^-1) and 0.24g VSS g^-1 PVA gel mainly composed of Methanosarcina spp. were got, while no natural granules were found in this experiment. The COD removal efficiency in this study could reach a high value about 95%. Most COD removal was contributed by the PVA-gel beads based biofilm. It could be concluded that the PVA-gel beads based biofilm reactor is appropriate for EGW treatment.