Degradation of the unbiodegradable particulate fraction (XU) from different activated sludges during batch digestion tests at ambient temperature

Efficacy of thermal hydrolysis for boosting specific methane yield depending on temperature-normalized solids retention time in an activated sludge process

“…In brief, WAS consists of active biomass (mainly active heterotrophic biomass X H and a few nitrifying autotrophic biomass X A ), inactive organic fractions like endogenous residues (X U,E ), inert components from the influent wastewater (X U,inf ), and inactive mineral fractions. 32 According to several studies, the fraction X H is mainly anaerobic biodegradable while X U,E and X U,inf remain largely unaffected 1,4,33,34 or have slow degradation rates (<0.012 d −1 ), [35][36][37] which come into effect for aerobic and anaerobic systems operated at long SRTs. The results of this study show that almost all viable cells (i.e.…”