A comparative study of thermophilic and mesophilic anaerobic co-digestion of food waste and wheat straw : Process stability and microbial community structure shifts
Copyright © 2018. Published by Elsevier Ltd.
Veröffentlicht in: | Waste management (New York, N.Y.). - 1999. - 75(2018) vom: 15. Mai, Seite 261-269 |
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Weitere Verfasser: | , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2018
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Zugriff auf das übergeordnete Werk: | Waste management (New York, N.Y.) |
Schlagworte: | Journal Article Anaerobic co-digestion Food waste and wheat straw Microbial community shift Thermophilic and mesophilic Biofuels Fatty Acids, Volatile Methane OP0UW79H66 |
Zusammenfassung: | Copyright © 2018. Published by Elsevier Ltd. Renewable energy recovery from organic solid waste via anaerobic digestion is a promising way to provide sustainable energy supply and eliminate environmental pollution. However, poor efficiency and operational problems hinder its wide application of anaerobic digestion. The effects of two key parameters, i.e. temperature and substrate characteristics on process stability and microbial community structure were studied using two lab-scale anaerobic reactors under thermophilic and mesophilic conditions. Both the reactors were fed with food waste (FW) and wheat straw (WS). The organic loading rates (OLRs) were maintained at a constant level of 3 kg VS/(m3·d). Five different FW:WS substrate ratios were utilized in different operational phases. The synergetic effects of co-digestion improved the stability and performance of the reactors. When FW was mono-digested, both reactors were unstable. The mesophilic reactor eventually failed due to volatile fatty acid accumulation. The thermophilic reactor had better performance compared to mesophilic one. The biogas production rate of the thermophilic reactor was 4.9-14.8% higher than that of mesophilic reactor throughout the experiment. The shifts in microbial community structures throughout the experiment in both thermophilic and mesophilic reactors were investigated. With increasing FW proportions, bacteria belonging to the phylum Thermotogae became predominant in the thermophilic reactor, while the phylum Bacteroidetes was predominant in the mesophilic reactor. The genus Methanosarcina was the predominant methanogen in the thermophilic reactor, while the genus Methanothrix remained predominant in the mesophilic reactor. The methanogenesis pathway shifted from acetoclastic to hydrogenotrophic when the mesophilic reactor experienced perturbations. Moreover, the population of lignocellulose-degrading microorganisms in the thermophilic reactor was higher than those in mesophilic reactor, which explained the better performance of the thermophilic reactor |
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Beschreibung: | Date Completed 13.08.2018 Date Revised 02.12.2018 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1879-2456 |
DOI: | 10.1016/j.wasman.2018.02.004 |