CORDIS OpenAire Sygma Archivio della ricerca - Università degli studi di Napoli Federico II HAL INRAE Bielefeld Academic Search Engine (BASE) FEDOA - IRIS Università degli Studi Napoli Federico II Crossref HAL Descartes Hal Microsoft Academic Graph European Union Open Data Portal https://www.iris.unina.it/bitstream/11588/743139/1/Batch%20Manuscript%20last%20for%20IRIS.pdf http://link.springer.com/content/pdf/10.1007/s13762-019-02264-z.pdf https://hal.inrae.fr/hal-02961893/file/Batch%20Manuscript_revf.pdf https://doi.org/10.1007/s13762-019-02264-z International Journal of Environmental Science and Technology Open Access 2019-02-12 2023-07-31 2019-03-01 Increasing total solids in anaerobic digestion can reduce the methane yield by highly complex bio-physical–chemical mechanisms. Therefore, understanding those mechanisms and their main drivers becomes crucial to optimize this waste treatment biotechnology. In this study, seven batch experiments were conducted to investigate the effects of increasing the initial total solids in high-solids anaerobic digestion of the organic fraction of municipal solid waste. With inoculum-to-substrate ratio = 1.5 g VS/g VS and maximum total solids ≤ 19.6%, mono-digestion of the organic fraction of municipal solid waste showed a methane yield = 174–236 NmL CH4/g VS. With inoculum-to-substrate ratio ≤ 1.0 g VS/g VS and maximum total solids ≥ 24.0%, mono-digestion experiments acidified. Co-digestion of the organic fraction of municipal solid waste and beech sawdust permitted to reduce the inoculum-to-substrate ratio to 0.16 g VS/g VS while increasing total solids up to 30.2%, though achieving a lower methane yield (117–156 NmL CH4/g VS). At each inoculum-to-substrate ratio, higher total solids corresponded to higher ammonia and volatile fatty acid accumulation. Thus, a 40% lower methane yield for mono-digestion was observed at a NH3 concentration ≥ 2.3 g N–NH3/kg reactor content and total solids = 15.0%. Meanwhile, co-digestion lowered the nitrogen content, being the risk of acidification exacerbated only at total solids ≥ 20.0%. Therefore, the biodegradability of the substrate, as well as the operational total solids and inoculum-to-substrate ratio, are closely interrelated parameters determining the success of methanogenesis, but also the risk of ammonia inhibition in high-solids anaerobic digestion. Environmental Engineering [SDE.IE]Environmental Sciences/Environmental Engineering Organic fraction of municipal solid waste 0211 other engineering and technologies 500 High-solids anaerobic digestion 02 engineering and technology Co-digestion 01 natural sciences 7. Clean energy 6. Clean water 12. Responsible consumption Agricultural and Biological Sciences (all) Thermophilic 13. Climate action Batch experiments 11. Sustainability Environmental Chemistry Volatile fatty acids [SDE.IE] Environmental Sciences/Environmental Engineering Batch experiments; Co-digestion; High-solids anaerobic digestion; Methane yield; Organic fraction of municipal solid waste; Thermophilic; Volatile fatty acids; Environmental Engineering; Environmental Chemistry; Agricultural and Biological Sciences (all) Methane yield 0105 earth and related environmental sciences Eric Trably, Jukka Rintala, Stefano Papirio, Vicente Pastor-Poquet, Vicente Pastor-Poquet, Vicente Pastor-Poquet, Giovanni Esposito, Renaud Escudié, 2019-02-12 journalpaper Increasing total solids in anaerobic digestion can reduce the methane yield by highly complex bio-physical–chemical mechanisms. Therefore, understanding those mechanisms and their main drivers becomes crucial to optimize this waste treatment biotechnology. In this study, seven batch experiments were conducted to investigate the effects of increasing the initial total solids in high-solids anaerobic digestion of the organic fraction of municipal solid waste. With inoculum-to-substrate ratio = 1.5 g VS/g VS and maximum total solids ≤ 19.6%, mono-digestion of the organic fraction of municipal solid waste showed a methane yield = 174–236 NmL CH4/g VS. With inoculum-to-substrate ratio ≤ 1.0 g VS/g VS and maximum total solids ≥ 24.0%, mono-digestion experiments acidified. Co-digestion of the organic fraction of municipal solid waste and beech sawdust permitted to reduce the inoculum-to-substrate ratio to 0.16 g VS/g VS while increasing total solids up to 30.2%, though achieving a lower methane yield (117–156 NmL CH4/g VS). At each inoculum-to-substrate ratio, higher total solids corresponded to higher ammonia and volatile fatty acid accumulation. Thus, a 40% lower methane yield for mono-digestion was observed at a NH3 concentration ≥ 2.3 g N–NH3/kg reactor content and total solids = 15.0%. Meanwhile, co-digestion lowered the nitrogen content, being the risk of acidification exacerbated only at total solids ≥ 20.0%. Therefore, the biodegradability of the substrate, as well as the operational total solids and inoculum-to-substrate ratio, are closely interrelated parameters determining the success of methanogenesis, but also the risk of ammonia inhibition in high-solids anaerobic digestion. High-solids anaerobic digestion requires a trade-off between total solids, inoculum-to-substrate ratio and ammonia inhibition 10.1007/s13762-019-02264-z