Respirometry for the assessment of biomass activity in Membrane Bioreactors

The aim of the study was to use respirometric techniques for the characterization of biomassbiokinetic behaviour in several MBR pilot plants characterized by different configurations,different operational conditions and fed with wastewater of different features(domestic/industrial). Four different MBR pilot plants were investigated: i) a sequencing batchMBR (SB-MBR) subjected to a gradual salinity increase; ii) a pre-denitrification MBR systemfor the treatment of saline wastewater contaminated by hydrocarbons; iii) a University of CapeTown MBR system (UCT-MBR) for the treatment of domestic wastewater subjected to acarbon-to-nitrogen (C/N) ratio variation; iiii) a UCT-IFAS-MBR for the treatment of domesticwastewater characterized by the variation of several operational parameters. The achievedresults highlighted the significant influence that plant configuration and operational conditionsmight exert on biomass respiratory activity, referring to both autotrophic and heterotrophicbacterial species.