Microalgae cultivation in wastewater

Research on biological processes for wastewater treatment (WWT) over the past decade has focused on the development of compact treatment processes at the expense of a high energy demand or a loss of valuable nutrients. The recent worldwide interest in the cultivation of microalgae for energy production, along with the need for more sustainable WWT processes, has turned microalgae-based WWT into a promising alternative to bacterial-based processes from an economic and environmental viewpoint. The O 2 produced photosynthetically by microalgae is used for the oxidation of organic matter and NH 4+ , while the autotrophic and heterotrophic metabolism of algal-bacteria consortia can support an enhanced nutrient recovery. This chapter presents a critical state-of-the-art review of the basis and applications of microalgae in the context of WWT in this 21st century