Impact of anaerobic digestion on organic matter quality in pig slurry Academic Article uri icon

abstract

  • Changes in pig slurry organic matter (OM) during anaerobic digestion (AD) were studied in a reactor to characterize OM evolution through AD. OM maturity and stability were evaluated using different biological and physico-chemical methods. Germination and growth chamber experiments revealed a higher maturity of digested slurry (DS) than raw slurry (RS). Soil incubations showed that DS was more stable than RS with a C-mineralization of 12.0 g CO2-C 100 g-1 Corg after 49 days as compared to 17.6 g CO2-C 100 g-1 Corg. Biochemical fractionation showed a relative increase in stable compounds such as hemicellulose-like and lignin-like molecules. Fourier-transform infrared spectroscopy showed some changes in the chemical structures of OM with a reduction in the aliphatic chain, lipid and polysaccharide levels. A comparison between the evolution of OM during AD and the first weeks of a composting process showed almost identical changes. Finally a theoretical method called Fictitious Atomic-group Separation was applied to the elemental compositions of RS and DS. DS was less humified than RS and presented the properties of a fulvic acid, indicating that the observed stability in DS was mainly due to the biodegradation of the most labile compounds. © 2008 Elsevier Ltd. All rights reserved.

author list (cited authors)

  • Marcato, C., Mohtar, R., Revel, J., Pouech, P., Hafidi, M., & Guiresse, M.

citation count

  • 61

publication date

  • April 2009