The role of starvation in biomass harvesting and lipid accumulation: Co-culture of microalgae-bacteria in synthetic wastewater

摘要

In this study, the microalgae-bacterial culture, composed of Chlorella vulgaris and activated sludge, was cultivated under starvation condition by controlling synthetic wastewater concentrations. After 8-day culturing, nutrients such as organic carbon, ammonium nitrogen and phosphate were basically removed. The dynamic formation phases of the microalgae-bacterial consortium were identified to microalgae adsorbed by sludge flocs, new bacteria adhesion on microalgae and bacteria uniformly distributed and attachment and detachment of biomass in balance. The consortiums had much better settle-ability than pure microalgae, and this phenomenon was particularly obvious in starvation term. Lipid accumulation of microalgae was also critically influenced by starvation cultivation, lipid content and lipid productivity of bioreactor with 5% initial wastewater (IW) were 17.1% and 0.045 g(Lday(-1))(-1). This study gave a new insight into formation processes of microalgae-bacterial consortium, and confirmed that starvation term was an effective strategy to enhance the consortium settle-ability and lipid accumulation capability. (c) 2015 American Institute of Chemical Engineers Environ Prog, 35: 103-109, 2016