A Two-Stage Process for Conversion of Brewer’s Spent Grain into Volatile Fatty Acids through Acidogenic Fermentation

This work is focused on the valorization of brewer’s spent grains (BSG) into volatile fatty acids (VFA) through acidogenic fermentation. VFAs are building blocks for several applications, such as bioplastics’ production. Using acid hydrolysis pre-treatment, batch assays were performed and impact organic load (OL) pH VFA production from BSG hydrolysate was assessed. Regardless condition, produced mainly butyric acetic followed by propionic acid. The OL had a direct total concentration with higher concentrations at highest (40 gCOD L?1). affected individual acid, fermentation products (FP) diversity attained 5.0 40 L?1. To assess potential application biopolymers (such polyhydroxyalkanoates) production, content in hydroxybutyrate (HB) hydroxyvalerate (HV) monomers estimated respective precursors each OL. HV increased pH, maximum 6.0 (ca. 16% C-mol basis). also assessed continuous operation, using an expanded granular sludge bed reactor (EGSB). It shown that successfully converted to without control, achieving productivities than operation mode.