Effect of ammoniacal Nitrogen on methanogenic metabolic pathways during MSW anaerobic digestion

Municipal solid waste (MSW) represents an important renewable energy sources and the sustainable management of organic wastes is a major environmental and economic issue. The anaerobic digestion of MSW, which occurs inlandfills and methanization treatment plants, is a very complex process. The final step of the waste degradation, i.e.methanogenesis, which produces methane, leads to the production of a biogas that could be transformed into heat,electric power and fuel gas (renewable energy). In order to produce more efficiently this renewable energy and toenhance the degradation of the organic fraction of waste, bioreactors landfill and methanization treatment plants are twopromising management strategies.

Further Authors:
J. Epissard - Irstea
M. Lemunier - Suez Environnement

However, these new strategies induce new processes failure. One of those is theaccumulation of ammonia produced from nitrogeneous compounds. The reason is that there is no efficient ammoniaelimination process under anaerobic conditions.An acetate-adapted landfill leachate microbial community was incubated anaerobically under mesophilic conditions(35°C) with acetate (3.3 g.L-1) at four different ammonia concentrations (0.180 g.L-1 to 5.4 g.L-1). Standardphysicochemical parameters were monitored together with CH4 and CO2 stable carbon isotopic signatures. Asmethanogenesis from H2/CO2 results in a larger fractionation against 13C than acetoclastic methanogenesis, the use ofstable isotopic signature of CH4 (δ13CH4) and CO2 (δ13CO2) can then allow to determine by which methanogenicpathways methane is produced. The objective of this study is to monitor methanogenic metabolic changes duringmethanization of acetate at various ammonia concentrations using the natural stable carbon isotopic signature ofmethane and carbon dioxide.Using this new tool, combined with standard physico-chemical monitoring, the results obtained in this work show that asudden increase of ammoniacal nitrogen concentration significantly influenced the methanogenic process of an acetateadapted-landfill inoculum. Indeed, ammonia concentration increase leads to various effects. CH4 stable carbon isotopecomposition evolution indicates a shift from the acetoclastic to hydrogenotrophic methanogenic pathway in function ofthe ammonia concentration. These results demonstrate that at high ammonia concentration acetate is consumed first byacetate oxidation followed by hydrogenotrophic methanogenesis (this reaction is then called syntrophic acetateoxidation). Ammonia concentration could then induce inhibition of acetoclastic methanogenesis. Even if the quantity ofmethane produced was the same at the end of all incubations, reaction rates of methane production were lower whenacetate was oxidized first.This work underlines the potential of the approach using carbon stable isotope measurement to study methanogenicprocesses. Indeed, isotopic approach could be a very useful tool to study AD process at different studies scales (i.e.laboratory and operational) as it allows a rapid and accurate monitoring of metabolic pathways involved duringmethanogenesis. A combination with microbial community structure analysis (using molecular microbiology techniques) could be very powerful to obtain a better understanding of methanogenic reactions.

Copyright: © European Compost Network ECN e.V.
Quelle: Orbit 2012 (Juni 2012)
Seiten: 8
Preis inkl. MwSt.: € 8,00
Autor: Théodore Bouchez
Dr Laurent Mazéas
J. Grossin-Debattista
H. Budzinski

Artikel weiterleiten In den Warenkorb legen Artikel kommentieren

Diese Fachartikel könnten Sie auch interessieren:

Multi-component heat and mass transport model for composting process: Experimental validation
© European Compost Network ECN e.V. (6/2012)
Composting consists in an aerobic process where the organic matter from wastes is biodegraded and converted into a stable granular material called compost. Even if composting is considered to be based on natural phenomenon, it is governed by very complex mechanisms, involving many parameters such as quality and accessibility of the nutriments for micro-organisms, local oxygen content, temperature of the medium, pH, moisture content, and so on (Mustin, 1987, Diaz et al., 2007;). These parameters directly affect biodegradation kinetics. Moreover, they are interdependent and impacted by the operating conditions, which make difficult the understanding of the process.

DINplus – Neue Anforderungen an kompostierbare Bioabfallsammelbeutel und Konsequenzen für die Praxis
© Witzenhausen-Institut für Abfall, Umwelt und Energie GmbH (4/2023)
Viele Haushalte entsorgen weiterhin Teile ihrer Bioabfälle über die Restmülltonne, weil die separate Sammlung als unsauber empfunden wird. Als Lösung werden neben Papierbeuteln auch feuchtigkeitsresistente Kunststoffbeutel angeboten, die als „kompostierbar“ zertifiziert sind. Eine Reihe von Kommunen haben mit solchen Beuteln gute Erfahrungen gemacht, in vielen örE werden sie aber auch abgelehnt – es wird befürchtet, dass die Bürger sie mit herkömmlichen Kunststoffbeuteln verwechseln und in den Verwertungsanlagen der biologische Abbau zu lange dauert. Als Antwort auf diese Befürchtungen sind in der novellierten Bioabfallverordnung konkrete Regelungen formuliert worden. Nachfolgend werden aktuelle Entwicklungen zu diesem Thema beschrieben.

Feldversuche zum Abbauverhalten von kompostierbaren Vorsammelhilfen in der technischen Kompostierung
© Witzenhausen-Institut für Abfall, Umwelt und Energie GmbH (4/2023)
Kompostierbare Vorsammelhilfen (zertifiziert nach EN 13432 und „OK Compost Home“) wurden zwei Versuchsmieten in „realitätsnahen“ Mengen zugesetzt, wobei eine theoretische Befüllung von 1 bis 1,2 kg Bioabfall pro Vorsammelhilfe erreicht wurde. Die Vorsammelhilfen fragmentierten bereits in den ersten beiden Rottewochen und verschwanden zwischen der zweiten und der vierten Woche in der Fraktion > 10 mm vollständig. Geringe Partikelanzahlen vom Typ der untersuchten Vorsammelhilfen konnten in der Fraktion 0,63 bis 0,2 mm in der Anlage 1 nach neun Wochen und in Anlage 2 nach zwölf Wochen nachgewiesen werden, wodurch gezeigt werden konnte, dass die untersuchten Vorsammelhilfen während der ordnungsgemäßen Kompostierung kaum zu Mikrokunststoffen fragmentiert.

Development of local municipal solid waste management in the Western Transdanubia region of Hungary
© Lehrstuhl für Abfallverwertungstechnik und Abfallwirtschaft der Montanuniversität Leoben (11/2020)
Hungarian municipal solid wastes (MSW) management has developed tremendously over the past 15 years. More than 3,000 landfills and dumps had been closed, just to mention one improvement. However, still, lots of work is necessary to accomplish the EU’s ambitious aim of decreasing landfilling and increasing recycling and composting.

Effects of alkaline pretreatment on the anaerobic digestion process of vegetables wastes
© European Compost Network ECN e.V. (6/2012)
Methane is produced by methanogenic bacteria from acetic acid, hydrogen and carbon dioxide and from other substrates of which formic acid and methanol are the most important (Bouallagui et al., 2005) during the anaerobic digestion of organic biomass. The objectives of this study consisted in setting up laboratory–scale biochemical methane potential (BMP) assay digesters at mesophilic conditions to assess the effectiveness of alkaline (NaOH) pretreatment in improving the anaerobic digestion process for biogas production from mixed vegetable wastes. Further Authors: A. Mudhoo - National Research Chair in Solid Waste Management, Mauritius V.D. Ramdeen - National Research Chair in Solid Waste Management, Mauritius



 Angemeldet bleiben

Passwort vergessen?

der Spezialist für biologische
und mechanisch-biologische
Verwertung organischer Stoffe