Abstract
One of the major factors that influences the economic feasibility of biogas production is the availability of digestible feedstocks. There is little research on the influence of the chemical composition of biomass on biogas synthesis, especially with regard to the content of lignocellulosic materials. Therefore, the aim of this study was to estimate how differences in the content of cellulose and lignin in lignocellulosic biomass influence the concentrations of individual volatile fatty acids (VFAs) and biogas production. Additionally, the structure of the methanogenic community was examined. The removal of fibrous and non-fibrous materials, the concentrations of individual VFAs, methane production and methanogen community structure were examined during digestion of Zea mays L. and Miscanthus sacchariflorus silages. Organics were removed with higher efficiency during the digestion of Z. mays silage than during digestion of M. sacchariflorus. This was due to the higher non-fibrous carbohydrates content in Z. mays than in M. sacchariflorus. In both digesters, propionate predominated throughout experiment. The methanogenic community in the digester fed with Z. mays was more diverse than that in the digester with M. sacchariflorus. Analysis of 16S rRNA sequences showed that six acetoclastic and four hydrogenotrophic methanogens were present in the digester fed with Z. mays L., while five acetoclastic and three hydrogenotrophic methanogens were in the digester fed with M. sacchariflorus. The abundance of Methanosarcina correlated significantly with the concentration of all analyzed VFAs.
Highlights
Anaerobic digestion (AD) is an important technology for simultaneously utilizing waste and producing biogas
Starch content was estimated by taking the difference between total carbohydrates and neutral detergent fibre (NDF); the content of hemicellulose was calculated as the difference between NDF and acid detergent fibre (ADF); whereas cellulose content, as the difference between ADF and acid detergent lignin (ADL) [8]
The organic loading rate (OLR) was similar in both series, the organics were removed with higher efficiency during the digestion of Z. mays L. silage than during that of M. sacchariflorus
Summary
Anaerobic digestion (AD) is an important technology for simultaneously utilizing waste and producing biogas. Waste and Biomass Valorization (2020) 11:1421–1433 not suitable for producing food, it may be possible to reduce the competition for land between food and energy crops, and mitigate the currently observed increase in demand from the bioenergy sector for vegetable food feedstocks. The pathways leading to formation of individual VFAs depend on several factors, such as the chemical composition of substrate and the operational conditions of digestion [1]. It is commonly believed that an increase in the concentration of VFAs can lead to process failure. One of the most common reasons for process deterioration is reactor acidification due to reactor overload. For this reason, many studies have focused on the relationship between VFAs accumulation and organic loading rate [2]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
