Vinasse as a business booster in the biorefinery concept: strategies to overcome anaerobic digestion bottlenecks to generate value-added products

• Grant number: 22/07127-5
• Support Opportunities: Regular Research Grants
• Duration: November 01, 2022 - October 31, 2025
• Field of knowledge: Engineering - Sanitary Engineering - Water Supply and Wastewater Treatment
• Convênio/Acordo: CONFAP - National Council of State Research Support Foundations
• Principal Investigator: Márcia Helena Rissato Zamariolli Damianovic
• Grantee: Márcia Helena Rissato Zamariolli Damianovic
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated researchers: Bruna Soares Fernandes ; Fabricio Motteran ; Valéria Del Nery

Abstract

The processing of wastewater generated in the agro-industrial sector has two main objectives: to mitigate harmful effects on the environment and to produce value-added by-products, converging on the concept of biorefinery. In the present research project, a system of continuous feed reactors is proposed for the anaerobic digestion of sugarcane vinasse in two stages, on a bench scale. The first stage is intended for acidogenesis and sulfetogenesis, aiming to remove sulfur compounds from the liquid phase and generate alkalinity for the subsequent phase. In the second stage of anaerobic digestion, the objective is to produce methane and evaluate the quality of the digested effluent. Structured fixed-bed reactors in sequential bench scale will be used, kept at a temperature of 30°C. Parallel experiments will be carried out in acidogenic batch reactors to increase the concentration of butyric acid present in fresh vinasse, using microbial consortia with Clostridium Butyricum. Sequentially, this effluent rich in butyric acid will feed a batch reactor, aiming to evaluate the elongation of the carbonic chain for the production of caproic acid, using three inoculums previously adapted and enriched under different conditions. Ethanol will be evaluated as a supplementary electron donor to the chain elongation process. In this way, this research project intends to provide biotechnological resources for generating energy from waste, recovering by-products (caproic acid), and reducing the emission of pollutants to the environment, thus contributing to the development of biotechnological DNA in sugar and ethanol plants and to the generation of new business opportunities. (AU)