TY - JOUR
T1 - Performance and microbial community analysis in alkaline two-stage enhanced anaerobic sludge digestion system
AU - Maspolim, Yogananda
AU - Guo, Chenghong
AU - Xiao, Keke
AU - Zhou, Yan
AU - Ng, Wun Jern
N1 - Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2016/1/15
Y1 - 2016/1/15
N2 - This study investigated an alkaline two-stage enhanced anaerobic sludge digestion system, which simultaneously combined biological and chemical mode of degradation. The alkaline enhanced mesophilic stage-1 was operated at pH 8 with 3 days hydraulic retention time (HRT), while the mesophilic stage-2 was without pH adjustment at 17 days HRT. The system achieved higher chemical oxygen demand (COD) removal, volatile solids (VS) reduction, and methane yield than the conventional 20 days HRT single-stage system. Further enhancement was obtained by moving the stage-1 from 35 to 55 °C, but it did not yield better energy balance with the 3 + 17 days HRT configuration implemented in this study. 454 pyrosequencing revealed the acclimation of specialized communities in the alkaline two-stage system. Methanosarcina, Methanobrevibacter and Methanothermobacter could survive at pH 8 in the alkaline enhanced stage-1 and contributed to regulating the potentially inhibitory volatile fatty acids (VFA) or hydrogen levels under the enhanced sludge solubilization and acidogenesis condition. Various fermentative populations, distinct to those in the single-stage system, were also enriched in the stage-1s. These populations could grow at pH 8, were transferred into the stage-2, and ensured continuity of the biochemical reactions under mild alkaline condition, leading to the enhanced sludge digestion process.
AB - This study investigated an alkaline two-stage enhanced anaerobic sludge digestion system, which simultaneously combined biological and chemical mode of degradation. The alkaline enhanced mesophilic stage-1 was operated at pH 8 with 3 days hydraulic retention time (HRT), while the mesophilic stage-2 was without pH adjustment at 17 days HRT. The system achieved higher chemical oxygen demand (COD) removal, volatile solids (VS) reduction, and methane yield than the conventional 20 days HRT single-stage system. Further enhancement was obtained by moving the stage-1 from 35 to 55 °C, but it did not yield better energy balance with the 3 + 17 days HRT configuration implemented in this study. 454 pyrosequencing revealed the acclimation of specialized communities in the alkaline two-stage system. Methanosarcina, Methanobrevibacter and Methanothermobacter could survive at pH 8 in the alkaline enhanced stage-1 and contributed to regulating the potentially inhibitory volatile fatty acids (VFA) or hydrogen levels under the enhanced sludge solubilization and acidogenesis condition. Various fermentative populations, distinct to those in the single-stage system, were also enriched in the stage-1s. These populations could grow at pH 8, were transferred into the stage-2, and ensured continuity of the biochemical reactions under mild alkaline condition, leading to the enhanced sludge digestion process.
KW - Anaerobic processes
KW - Biogas
KW - Bioreactors
KW - Microbial community
KW - Two-stage anaerobic digestion
KW - Waste treatment
UR - http://www.scopus.com/inward/record.url?scp=84961879648&partnerID=8YFLogxK
U2 - 10.1016/j.bej.2015.10.004
DO - 10.1016/j.bej.2015.10.004
M3 - 文章
AN - SCOPUS:84961879648
SN - 1369-703X
VL - 105
SP - 296
EP - 305
JO - Biochemical Engineering Journal
JF - Biochemical Engineering Journal
ER -