Study on biological phosphorus removal process by Acinetobacter lwoffi: possibility to by-pass the anaerobic phase

Abstract

An Acinetobacter lwoffi culture has been submitted to anaerobic/aerobic conditions in a Sequencing Batch Reactor (SBR) in order to study the ability of this strain in biological phosphorus removal process. Even by feeding a pure sodium acetate substrate, no phosphorus release has been detected during anaerobiosis, while phosphorus uptake beyond metabolic needs has been recorded during the aerobic phase; the anaerobic phase seems to have no influence on the enhanced biological phosphorus removal mechanisms. Hence aerobic batch tests have been carried out in order to verify the ability of Acinetobacter lwoffi to remove phosphorus by “luxury uptake” and “overplus accumulation” without anaerobic stress. Obtained results revealed a phosphorus removal efficiency of 75–80%.