MEMBRANE PHOTOBIOREACTOR FOR MICROALGAE CULTIVATION: APPLICATION TO EXTRACELLULAR GLYCEROL PRODUCTION AND TERTIARY WASTEWATER TREATMENT.

Abstract

Photosynthetic microalgae can be used as bio-factories to produce value-added chemicals from carbon dioxide, light and nutrients. These microorganisms can also be used in wastewater treatment, to simultaneously capture CO2, generate biomass and remove nutrients. Recently, membrane photobioreactors (MPBR) have emerged as a new technology for continuous microalgae cultivation. In this research, microfiltration-based MPBRs have been designed and operated for glycerol production and for tertiary wastewater treatment. In the first part of the research, the focus was on continuous production of extracellular glycerol from Dunaliella tertiolecta under hypersaline conditions. A high concentration of biomass was obtained in the MPBR, such that a large amount of glycerol could be recovered in the effluent. In the second part, the focus was on tertiary wastewater treatment in an MPBR using Chlorella vulgaris. The MPBR was integrated to a membrane bioreactor operating with activated sludge and treating wastewater from food waste digestate.