The Use of Microalgae and Cyanobacteria for Wastewater Treatment and the Sustainable Production of Biomass

Biological and physicochemical wastewater treatment systems are sometimes inefficient and consume high energy. The wastewater discharged usually contains compounds of carbon, nitrogen, phosphor, and other micronutrients in considerable amounts, which can be used for the development of microalgae and cyanobacteria cultures. These microorganisms are photosynthetic and can grow in water bodies with the necessary nutrients. On the other hand, there is a need to reduce the generated costs by the consumption of chemicals in the production of microalgae and cyanobacteria biomass. Therefore, the integration into wastewater systems is emerging as an opportunity to develop efficient treatment methods that allow the profitable production of high value-added and innovative bioproducts with industrial applications that at the same time promote a circular bioeconomy. The aim of this chapter is to identify the current issues and the actual studied trends with the potential use of microalgae and cyanobacteria as a system of water treatment and the generation of biomass. Also, the main mechanisms that influence wastewater treatment with microalgae and cyanobacteria are provided, along with the main bioproducts obtained from the biomass generated in these processes and future trends in this area.