Feasibility of dry anaerobic digestion of beer lees for methane production and biochar enhanced performance at mesophilic and thermophilic temperature

Abstract

This study investigated the feasibility of dry anaerobic digestion using beer lees as substrate and the effect of cow manure-derived biochar addition on dry anaerobic digestion performance at mesophilic and thermophilic temperature, respectively. With TS content of 25%, maximum cumulative methane production and yield were achieved to be 5230 ± 91 mL d−1 and 220.1 ± 7.7 mL g−1 VS at mesophilic condition and 7386 ± 134 mL d−1 and 310.4 ± 9.2 mL g−1 VS at thermophilic condition in the control cultures. The biochar addition has a positive effect in improving dry anaerobic digestion performance. The maximum cumulative methane production and yield in the cultures with 10 g L−1 biochar were substantially improved by 82.9% and 82.6% at mesophilic condition and 47.2% and 46.8% at mesophilic condition when compared to the control.