TY - JOUR
T1 - Biomethanation and microbial community changes in a digester treating sludge from a brackish aquaculture recirculation system
AU - Zhang, Xuedong
AU - Tao, Yu
AU - Hu, Jianmei
AU - Liu, Gang
AU - Spanjers, Henri
AU - van Lier, Jules
PY - 2016
Y1 - 2016
N2 - Using a high-salinity-adapted inoculum and a moderate stepwise-increased organic loading rate (OLR), a stable digester performance was achieved in treating sludge from a brackish aquaculture recirculation system. The specific methane yield was distinctly enhanced, reaching 0.203 L CH4/g CODadded, compared to literature values (0.140–0.154 L CH4/g CODadded) from the salty sludges. OLR adjustment and the fecal substrate substantially influenced population changes in the digester. Within the bacterial subpopulations, the relative abundance of Bacillus and Bacteroides declined, accompanied by the increase of Clostridium and Trigonala over time. The results show Trigonala was derived from the substrate and accumulated inside the digester. The most abundant methanogen was Methanosarcina in the inoculum and the digestates. The Methanosarcina proliferation can be ascribed to its metabolic versatility, probably a feature of crucial importance for high-salinity environments. Other frequently observed methanogens were outcompeted. The population similarity at the genus level between inoculum and digestates declined during the initial stage and afterwards increased.
AB - Using a high-salinity-adapted inoculum and a moderate stepwise-increased organic loading rate (OLR), a stable digester performance was achieved in treating sludge from a brackish aquaculture recirculation system. The specific methane yield was distinctly enhanced, reaching 0.203 L CH4/g CODadded, compared to literature values (0.140–0.154 L CH4/g CODadded) from the salty sludges. OLR adjustment and the fecal substrate substantially influenced population changes in the digester. Within the bacterial subpopulations, the relative abundance of Bacillus and Bacteroides declined, accompanied by the increase of Clostridium and Trigonala over time. The results show Trigonala was derived from the substrate and accumulated inside the digester. The most abundant methanogen was Methanosarcina in the inoculum and the digestates. The Methanosarcina proliferation can be ascribed to its metabolic versatility, probably a feature of crucial importance for high-salinity environments. Other frequently observed methanogens were outcompeted. The population similarity at the genus level between inoculum and digestates declined during the initial stage and afterwards increased.
KW - Anaerobic digestion
KW - Brackish aquaculture recirculation systems
KW - Stepwise increased OLR
KW - Sludge retention time (SRT)
KW - Inoculum
KW - Bacterial and archaeal population
U2 - 10.1016/j.biortech.2016.04.120
DO - 10.1016/j.biortech.2016.04.120
M3 - Article
SN - 0960-8524
VL - 214
SP - 338
EP - 347
JO - Bioresource Technology
JF - Bioresource Technology
ER -