RESUMO
This study investigated the impact of different granular activated carbon (GAC) loadings and inoculum enrichment on acidogenic fermentation of food waste in a leachate bed reactor (LBR) operated at a high volumetric organic loading of 49â¯g VS/Lreactor. LBR with a high GAC loading of 0.51â¯g GAC/g VSfood waste achieved hydrolysis yield of 620â¯g SCOD/kg VSadded, significantly (Pâ¯≤â¯0.05) higher to that obtained for LBRs with low or no GAC loading. A high GAC loading also resulted in a higher acidification yield of 507â¯g CODSCFA/kg VSadded. Butyrate dominated the short-chain fatty acid (SCFA) composition by constituting 57-60â¯% of total SCFA at high GAC loadings, while the composition of acetate (38-40â¯%) and butyrate (36-38â¯%) were similar at lower GAC loadings. Inoculum enrichment further improved the hydrolysis and acidogenesis yields by 10-22â¯% resulting in the final hydrolysis yield of 683â¯g SCOD/kg VSadded and acidification yield of 617â¯g CODSCFA/kg VSadded.