Production of microalgae in wastewater and brackish waters: kinetic, lipid content, bioremediation and cost analysis studies

The cultivation of microalgae in domestic wastewater offers a sustainable solution for the treatment of effluents, while at the same time producing biomass rich in lipids, potentially usable in the production of biofuels. Furthermore, reuse contributes to the treatment of wastewater, transforming a byproduct into a valuable source of nutrients for the production of microalgae biomass. This study involves the production of microalgae in open cultivation, using domestic effluents as a source of nutrients in brackish environments, to study the potential for biodiesel production. Intracellular lipids were between 17 and 20%. As for the bioremediation capacity, the results showed removal levels greater than 95% of nutrients, as well as bacterial and pollutant load reduction. The growth kinetics and the prediction of theoretical kinetic models through the use of computational tools show significant differences, due to the lack of control of process parameters in open cultivations. Based on the literature review and market research, a cost analysis for large-scale production in open crops was made, comparing with closed crops and finding lower costs in the implementation, maintenance and production of biodiesel in the production open.