Integration of Sustainable Biotechnology: Microalgae in Microbial Fuel Cells for Bioremediation and Bioenergy From Livestock Waste

Sustainable waste management has advanced from pollution control to resource recovery. This study explores the integration of microbial fuel cells (MFCs) with microalgae biotechnology for simultaneous wastewater bioremediation, bioelectricity generation, and biomass production. Microalgae enhance the system by photosynthesizing CO₂, supplying oxygen for cathodic reactions, and producing valuable biomass. In Brazil, a major beef producer, livestock waste poses serious environmental risks. This work evaluated the performance of microalgae in wastewater from confined beef cattle production using four concentrations (5%, 20%, 35%, and 50%) in a 1×4 factorial design with triplicates. Bioremediation, energy generation, and biomass characteristics were assessed using SEM and EDX. The 20% concentration delivered optimal results: 50% phosphorus, 30% nitrogen, and 7% potassium reduction; 2.142 μW maximum power; 0.51 μA current; and 4.2 mV voltage. SEM revealed biofilm formation on the anode, while EDX confirmed phosphorus (4.26%) and magnesium (4.03%) bioaccumulation. The integrated system efficiently treats wastewater while generating clean energy and high-value biomass, such as biofuels and animal feed. This approach supports the Sustainable Development Goals (SDGs) and underscores Brazil’s potential to lead in sustainable agribusiness technologies.