Comparative analysis of concentration technologies: designing biorefineries for vinasse resource recovery

• Autor(a) principal: Peiter, Fernanda Santana
• Data de Publicação: 2018
• Tipo de documento: Tese
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: http://www.teses.usp.br/teses/disponiveis/18/18138/tde-24052019-142619/
• topic: Anaerobic digestion; Análise de exergia; Biorrefinaria; Concentração; Concentration methods; Digestão anaeróbia; Exergy Analysis; Vinasse biorefinery; Vinhaça

Vinasse, a wastewater rich in organic matter, nutrient and water, is commonly used for fertigation of sugarcane plantation. However, this practice is questionable in the environmental sphere because of problems, such as contamination of groundwater and greenhouse gases emission. Researchers have sought for alternatives that use vinasse in a more sustainable way, e.g., biorefineries that recover resources. In general, the pathways considered are the concentration technologies to reclaim water and nutrient, and the anaerobic digestion (AD) to produce biogas. This thesis reports on a study of five designs of vinasse biorefineries that incorporate anaerobic bioreactors followed by a concentration technology (evaporation (EV), reverse osmosis (RO) or forward osmosis (FO)). Different forms of regeneration of the draw solution (DS) namely evaporation, reverse osmosis and membrane distillation (MD) were also analyzed. The alternatives were compared through an exergy analysis, a method that evaluates efficiency in the conversion of resources by systems. The results showed Alternative 2 (anaerobic digestion + reverse osmosis) was the most efficient (64%), since the treatment of 491.76 m3 vinasse h-1 (exergy content of 60513.8 kW) to recover 80% of water reduced 76% of external water requirement and generated 12% more electricity (2601 kW exergy) for the industry.