Determining C/N ratios for typical organic wastes using biodegradable fractions
Puyuelo Sánchez, Belén (Universitat Autònoma de Barcelona. Departament d'Enginyeria Química, Biològica i Ambiental)
Ponsá Salas, Sergio (Universitat Autònoma de Barcelona. Departament d'Enginyeria Química, Biològica i Ambiental)
Gea Leiva, Teresa (Universitat Autònoma de Barcelona. Departament d'Enginyeria Química, Biològica i Ambiental)
Sanchez, Antoni (Universitat Autònoma de Barcelona. Departament d'Enginyeria Química, Biològica i Ambiental)

Date:	2011
Abstract:	It is well established that an optimal aerobic and anaerobic microbial metabolism is achieved with a C/N ratio between 20 and 30. Most studies are currently based on chemically-measured carbon and nitrogen contents. However, some organic wastes can be composed of recalcitrant carbon fractions that are not bioavailable. To know the biodegradable C/N ratio, two different methods to determine the aerobic and anaerobic biodegradable organic carbon (BOC AE [subíndex] and BOC AN [subíndex]) are proposed and used to analyze a wide variety of different organic samples. In general, raw wastes and digested products have more amount of BOCAE. On the contrast, the samples collected after an aerobic treatment have higher content of BOC AN [subíndex]. In any case, all the BOC fractions are lower than the total organic carbon (TOC). Therefore, the C/N ratios based on BOC are always lower than the total C/N ratio based on the TOC measure. The knowledge of the real bioavailable C/N ratio is crucial for the biological treatments of organic materials. To reduce the test time necessary for BOC determination, the values of BOC for all the samples obtained at different times were compared and correlated with the final BOC. A method that allows for the determination of BOC AE [subíndex] in 4 d is proposed. In relation to the anaerobic assay, the biogas potential calculated after 21 and 50 d was positively correlated with the final potential defined after 100 d of assay.
Grants:	Ministerio de Ciencia e Innovación CTM2009-14073-C02-01
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió sotmesa a revisió
Subject:	Biodegradable organic carbon (BOC) ; Total organic carbon (TOC) ; Bioavailability ; Respiration index ; Biogas potential ; C/N ratio
Published in:	Chemosphere, Vol. 85, Issue 4 (Oct. 2011) , p. 653-659, ISSN 1879-1298

DOI: 10.1016/j.chemosphere.2011.07.014

Pre-print 30 p, 593.6 KB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Engineering > Composting Research Group (GICOM)
Articles > Research articles
Articles > Published articles