Nutrient removal in a sequencing batch biofilm reactor (SBBR) using a vertically moving biofilm system

In this paper, the performance of a sequencing batch biofilm reactor (SBBR) using an anoxic anaerobic phase followed by an aerobic phase for nutrient removal from wastewater was investigated. In the laboratory SBBR unit, biofilm was grown on a plastic biofilm media module, which was vertically moved up into the air and down into the bulk fluid during the aerobic phase. The vertical movement of the biofilm module supplied oxygen to the microorganisms. The module was submerged in the wastewater during the anoxic anaerobic phase. The percentage removals of total chemical oxygen demand (COD), total nitrogen (TN) and soluble orthophosphate (PO4-P) were 95.4%, 68.3% and 89.5% respectively at influent concentrations of COD 773 mg l(-1), TN 49.9 mg l(-1) and PO4-P 16.5 mg l(-1). The effluent COD was 35 mg l(-1), NH4-N 10.2 mg l(-1), NO3-N 5.5 mg l(-1), soluble PO4-P 1.7 mg l(-1) and suspended solids (SS) 19 mg l(-1).