Assessment of Oxygen Transfer, Uptake and Energy Footprint of Full Scale SSM IFAS Systems using Off-gas Testing

Structured sheet media (SSM) integrated fixed-film activated sludge (IFAS) systems have been installed in various existing wastewater treatment plants for enhanced secondary and/or tertiary nitrification especially for under cold weather conditions (Ye et al., 2010c; Flamming et al., 2011; Zhu et al., 2012a and 2012b). The SSM IFAS systems have demonstrated to be compatible with fine bubble diffusers for enhanced biofilm control and oxygen transfer efficiency with dedicated airlift pumping and scouring over the entire media surface (Ye et al., 2009, 2010a, 2010b). The impact of SSM on fine bubble diffuser oxygen transfer efficiency (OTE) in clean water has previously been studied (Zhu et al., 2011). The oxygen transfer, uptake and aeration air use of full scale SSM IFAS systems, however, have not been explored in the past. This paper presents the findings of off-gas testing at the Cocalico Valley Poultry Farm (CVPF), PA, Spring Township, PA and Coldwater, MI wastewater treatment plants (WWTPs).