Reuse of By-products from the Sugar and Alcohol Sector for Biogas Production

Greenhouse gas (GHG) emissions are a primary driver of climate change, emphasizing the need for sustainable energy solutions. In Brazil, the sugar and ethanol industry are key components of agribusiness, contributing significantly to the national economy. However, this sector produces large quantities of vinasse and bagasse as by-products of ethanol generation, posing significant environmental challenges. Effective management of these residues is essential for reducing their ecological footprint and enhancing the sustainability of the production chain. This review explores anaerobic biodigestion as a promising strategy for converting vinasse and bagasse into valuable biogas and digestate. Biogas, a renewable energy source primarily composed of methane, can reduce reliance on fossil fuels, while digestate can be used as a biofertilizer, closing the loop in agricultural production. The review discusses the biological processes involved in anaerobic biodigestion, with a focus on microbial communities and key operational parameters that influence process efficiency, such as temperature, pH, and co-digestion strategies. We also examine recent technological advancements and case studies that highlight the feasibility and benefits of integrating anaerobic biodigestion into the sugar and ethanol sector. By detailed literature research, this review underscores the potential of biodigestion to reduce GHG emissions, minimize waste, and contribute to the development of a circular economy. Ultimately, the adoption of anaerobic biodigestion can play a crucial role in supporting Brazil’s transition toward a more sustainable and low-carbon energy future.