TY - JOUR
AU1 - Jayakrishnan, U.
AU2 - Ghosh, Debolina
AU3 - Deka, Deepmoni
AU4 - Das, Gopal
AB - The study investigates the influence of sludge retention time (SRT), accumulation strategies, and acidogenic fermentation of rice mill effluent (RME) in enhancing the bioconversion to polyhydroxybutyrate (PHB) by activated sludge. Volatile fatty acid (VFA) content increased six-fold with acidification of 79.4 ± 0.005% after the fermentation of RME. The short-term feast-famine enrichment enhanced the storage response of activated sludge by six-fold compared to raw sludge. The maximum PHB accumulation of 60.4 ± 0.004% and 29.5 ± 0.01% was observed using acetate and fermented RME as substrate, respectively, under pulse-wise feeding using 10d SRT enriched sludge than other combinations. PHB yield and specific storage rates were also several folds higher for sludge enriched under 10d SRT than 5d SRT. The storage response also increased more than twice using fermented RME than raw RME. Alpha diversity analysis indicates reduced species richness, with classes Clostridia and Gammaproteobacteria performing a significant share of VFA and PHB production, respectively. Biocrude production from sludge wasted during enrichment was also demonstrated in the study. During the short-term enrichment, the limited exposure to selective pressure and washout of a portion of culture due to the faster growth demand of shorter SRT reduces storage capacity compared to longer SRT. In addition, a carbon-excess condition in the fed-batch regime and improved PHB precursor content after acidogenesis of RME maximizes PHB accumulation. Hence, the study’s outcomes would have particular relevance in balancing waste management through valorization in a waste biorefinery approach.
TI - Effect of sludge retention time and feeding strategy on polyhydroxybutyrate production from rice mill effluent using activated sludge
JF - Biomass Conversion and Biorefinery
DO - 10.1007/s13399-022-03321-3
DA - 2022-10-08
UR - https://www.deepdyve.com/lp/springer-journals/effect-of-sludge-retention-time-and-feeding-strategy-on-ucF3mlaSIg
SP - 1
EP - 23
VL - OnlineFirst
IS - 
DP - DeepDyve
ER -