TY - JOUR
T1 - Laboratory-scale bioreactors for soluble selenium removal from selenium refinery wastewater using anaerobic sludge
AU - Soda, Satoshi
AU - Kashiwa, Masami
AU - Kagami, Tsubasa
AU - Kuroda, Masashi
AU - Yamashita, Mitsuo
AU - Ike, Michihiko
PY - 2011/9/15
Y1 - 2011/9/15
N2 - Laboratory-scale bioreactors were constructed to investigate their applicability for recovery of soluble selenium from industrial wastewater. Microbial reduction of soluble selenium into elemental selenium is the key reaction because, as a result of its insoluble characteristics, it can be removed easily from the aqueous phase. Wastewater of a selenium refinery plant showed extremely low pH (<1.0), high salinity (6-7%), and various selenium concentrations (mainly selenite, 13.2-74.0mgl-1). As preconditioning for microbial reduction, the wastewater pH and salinity were adjusted, respectively, to about 7.5 and 1.1%. Granular sludge of an up-flow anaerobic sludge blanket (UASB) reactor and suspended sludge of a sewage sludge digester were seeded respectively to a UASB-type reactor and a suspended sludge bed reactor. The 2.2-l bioreactors were operated at 30°C and hydraulic retention time of about 24h for preconditioned wastewater supplemented with ethanol as a carbon source. The removal of 1.5-3.5mgl-1 soluble selenium was only 60% in the swim-bed reactor. The selenium concentration in effluent of the UASB-type reactor dropped to less than the regulated amount of the effluent concentration of selenium of 0.1mgl-1 by day 15.
AB - Laboratory-scale bioreactors were constructed to investigate their applicability for recovery of soluble selenium from industrial wastewater. Microbial reduction of soluble selenium into elemental selenium is the key reaction because, as a result of its insoluble characteristics, it can be removed easily from the aqueous phase. Wastewater of a selenium refinery plant showed extremely low pH (<1.0), high salinity (6-7%), and various selenium concentrations (mainly selenite, 13.2-74.0mgl-1). As preconditioning for microbial reduction, the wastewater pH and salinity were adjusted, respectively, to about 7.5 and 1.1%. Granular sludge of an up-flow anaerobic sludge blanket (UASB) reactor and suspended sludge of a sewage sludge digester were seeded respectively to a UASB-type reactor and a suspended sludge bed reactor. The 2.2-l bioreactors were operated at 30°C and hydraulic retention time of about 24h for preconditioned wastewater supplemented with ethanol as a carbon source. The removal of 1.5-3.5mgl-1 soluble selenium was only 60% in the swim-bed reactor. The selenium concentration in effluent of the UASB-type reactor dropped to less than the regulated amount of the effluent concentration of selenium of 0.1mgl-1 by day 15.
KW - Anaerobic sludge
KW - Metal refinery wastewater
KW - Selenium
KW - UASB reactor
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U2 - 10.1016/j.desal.2011.06.031
DO - 10.1016/j.desal.2011.06.031
M3 - Article
AN - SCOPUS:80052344433
VL - 279
SP - 433
EP - 438
JO - Desalination
JF - Desalination
SN - 0011-9164
IS - 1-3
ER -