Evaluation of Biomass, Lipid and Chlorophyll Production of a Microalgal Consortium Cultured in Dairy Wastewater

Currently, microalgae cultivation requires strategies to improve yield and reduce production costs for biotechnological purposes. Dual-purpose systems are one of the most widely used strategies for these purposes, using culture media supplemented with wastewater. This study evaluated the growth of a microalgal consortium in three treatments with different proportions of dairy wastewater (WWDI) and synthetic BBM-3N medium (Bold Basal Medium), with the aim of optimizing biomass, chlorophyll, and lipid production. The treatment with 60% BBM-3N medium and 40% WWDI (Case 3) showed the best performance under experimental conditions, reaching a biomass concentration of 0.7543 g/L, a chlorophyll production of 10.6890 µg/mL, and a lipid content of 14.63%. These results exceeded those obtained in the cases with 100% BBM-3N or 100% WWDI. In addition, a techno-economic evaluation was carried out via SuperPro Designer simulation, which allowed the annual operating costs for each treatment to be estimated. Case 3 stood out as the most viable option, combining good biological performance with lower operating costs compared to the raw material, demonstrating the potential of using wastewater as a partial source of nutrients in microalgal cultures intended for the production of value-added products.