Anaerobic co-digestion of urban, agro-industrial and agricultural organic wastes: recovery of biogas, nutrients and water

• Grant number: 22/03924-8
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Regular Program Grants
• Start date: July 01, 2023
• End date: June 30, 2025
• Field of knowledge: Engineering - Sanitary Engineering - Water Supply and Wastewater Treatment
• Agreement: Secretaria de Meio Ambiente, Infraestrutura e Logística - Fundação Florestal
• Principal Investigator: Roberto Alves de Oliveira
• Grantee: Roberto Alves de Oliveira
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated researchers: Leonardo Lucas Madaleno ; Maria Inês Tiraboschi Ferro ; Rose Maria Duda ; Valciney Gomes de Barros

Abstract

This work will be supported by the anaerobic co-digestion of solid vegetable waste coming from warehouses, supermarkets and street fairs, with sludge from the water treatment station for public supply (WTP), vinasse and filter cake from the sugarcane industry, and swine wastewater, using different combinations, proportions and strategies for the production of biogas and the recovery of nutrients and water. Co-digestion will be carried out in three sets of up-flow anaerobic sludge blanket reactors (UASB) in two stages on a pilot scale. The work will be divided into six subprojects for co-digestion with the objective of bioenergy production and two subprojects for the post-treatment of effluents aiming to recover nutrients and water. Our co-digest subprojects will be evaluated on the combination of two vegetable residues in different proportions, such as (1) WTP sludge, (2) vinasse and filter cake and (3) swine wastewater. Subsequently, in the second year of the project, the co-digestion of: (4) vegetable waste, WTP sludge, vinasse and filter cake, (5) vegetable waste, vinasse and swine wastewater and (6) vegetable waste, swine wastewater and WTP sludge. One anaerobic continuous stirred-tank reactor (CSTR) will also be operated with the codigestion that present better methane production in the UASB reactors in the first (subprojects 1, 2 or 3) and second (subprojects 4, 5 or 6) years, and in the similar operational conditions (influent suspended solids concentration, hydraulic detention time (HDT), organic loading rate (OLR) and solids retention time (SRT)) more appropriate to CSTR. The effluents from UASB and CSTR reactors, apart from decantation, will be submitted to the advanced oxidation process (Fenton) (subproject 7) to obtain reuse water, and tests will also be carried out for the recovery of nutrients, mainly N, P and Mg in the form of struvite (subproject 8). It is expected that the co-digestion and post-treatment of urban, industrial and agricultural waste can provide a significant reduction in the concentration of carbonaceous material, producing biogas and water for reuse with the recovery of macronutrients for agriculture, allowing the rational use and recovery of the materials and energy contained in these by-products of critical production processes, within a very favourable and sustainable cost-benefit ratio in the social, economic and environmental fields. (AU)