Degradation of Extracellular Polymeric Substances (EPS) in anaerobic digestion of dewatered sludge

The degradation of extracellular polymeric substances based on high-solid anaerobic digestion was investigated by gel filtration chromatography (GFC) and three-dimensional excitation and emission matrix (EEM) The organic matters of Extracellular Polymeric Substances (EPS) in the sludge decreased 24% and shifted from the tightly bound EPS (TB-EPS) fraction to the Slime fraction during anaerobic digestion. The raw sludge and the digestate had opposite molecular weights (MW) distribution in EPS fractions. From the fluorescence spectra result, tyrosine-like substances were converted to tryptophan-like substances, and more humic-like substance in Slime fration was produced with the reduction of the protein-like substance during anaerobic digestion. (C) 2013 The Authors. Published by Elsevier B.V.