Biohydrogen production by anaerobic digestion of glycerin in thermophilic condition: evaluation of possible inhibition

• Grant number: 21/05637-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2021
• End date: December 31, 2022
• Field of knowledge: Engineering - Sanitary Engineering - Water Supply and Wastewater Treatment
• Principal Investigator: Giovanna Lovato
• Grantee: Arthur Gregorio Barbosa Tavares
• Host Institution: Escola de Engenharia Mauá (EEM). Instituto Mauá de Tecnologia. São Caetano do Sul , SP, Brazil

Abstract

Glycerin is the major byproduct of the biodiesel industry. For every 100 kg of biodiesel produced, approximately 10 kg of crude glycerol are generated and the excess production of this residue can hardly be sold in full to industries. However, it is a biologically degradable residue and it becomes a substrate in the hydrogen production process by anaerobic digestion. The process of H2 production by anaerobiosis at thermophilic temperatures has advantages over the mesophilic process, such as greater yield and stability, however the group from the Biochemical Engineering Laboratory of the Mauá Institute of Technology found it difficult to produce this biogas at 55 ° C from glycerin. Scientific literature provides evidence that this residue may have antimicrobial properties, but this effect is unknown within the context of anaerobic digestion. Therefore, the present work aims to evaluate a possible inhibition of the hydrogen production process by glycerin anaerobic digestion in thermophilic condition. Assays will be carried out at different temperatures (45 and 50 ° C) with different influent concentrations of glycerin (0, 1150, 2300, 3450 and 4600 mgGlycerin.L-1) using an anaerobic bioreactor operated in sequential batches. Biohydrogen stability and productivity, the yield factor between generated hydrogen and consumed organic matter and the organic matter conversion efficiency will be evaluated. In addition, kinetic and thermodynamic models of biochemical reactions will be adjusted to experimental data to verify the possible occurrence of inhibition. (AU)