title: Anaerobic co-digestion of spent coffee grounds with different waste feedstocks for biogas production.
abstract: Proper management of spent coffee grounds has become a challenging problem as the production of this waste residue has increased rapidly worldwide. This study investigated the feasibility of the anaerobic co-digestion of spent coffee ground with various organic wastes, i.e., food waste, Ulva, waste activated sludge, and whey, for biomethanation. The effect of co-digestion was evaluated for each tested co-substrate in batch biochemical methane potential tests by varying the substrate mixing ratio. Co-digestion with waste activated sludge had an apparent negative effect on both the yield and production rate of methane. Meanwhile, the other co-substrates enhanced the reaction rate while maintaining methane production at a comparable or higher level to that of the mono-digestion of spent coffee ground. The reaction rate increased with the proportion of co-substrates without a significant loss in methanation potential. These results suggest the potential to reduce the reaction time and thus the reactor capacity without compromising methane production.
authors.affiliation: School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea.
authors.forename: Jaai
authors.initials: J
authors.lastname: Kim
authors.affiliation: School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea.
authors.forename: Hakchan
authors.initials: H
authors.lastname: Kim
authors.affiliation: School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea.
authors.forename: Gahyun
authors.initials: G
authors.lastname: Baek
authors.affiliation: School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea. Electronic address: cslee@unist.ac.kr.
authors.forename: Changsoo
authors.initials: C
authors.lastname: Lee
mesh_terms: D000693:Anaerobiosis; D056804:Biofuels / Q000032:analysis*; D019149:Bioreactors; D003069:Coffee / Q000737:chemistry*; D005735:Garbage; D012037:Refuse Disposal; D012722:Sewage / Q000737:chemistry*; D044445:Ulva / Q000378:metabolism*; D018505:Waste Management / Q000379:methods*; D000067796:Whey / Q000737:chemistry*
chemical_list: D056804:Biofuels; D003069:Coffee; D012722:Sewage
keywords: Anaerobic co-digestion; Biochemical methane potential; Kinetic modeling; Spent coffee grounds