TY - JOUR
T1 - Rapid autohydrogenotrophic denitrification by a membrane biofilm reactor equipped with a fibrous support around a gas-permeable membrane
AU - Terada, A.
AU - Kaku, S.
AU - Matsumoto, S.
AU - Tsuneda, S.
N1 - Funding Information:
We are grateful to Yoshie Kaifu of Waseda University Environment Safety Center for providing useful information regarding the measurement of hydrogen in water. A. Terada was individually supported by a Research Fellowships for Young Scientists from the Japan Society for the Promotion of Science.
PY - 2006/8/1
Y1 - 2006/8/1
N2 - A hydrogen-based membrane biofilm reactor (MBfR), employing fibrous slag as a bacterial carrier, was developed for rapid and stable autohydrogenotrophic denitrification. This reactor allows hydrogen to be supplied through a gas-permeable membrane to the biofilm supported by fibrous slag. The estimation of hydrogen supply rate clearly demonstrated that hydrogen flux (JH2) is dependent on the gas pressure, leading to a possibility to control JH2 by adjusting the pressure. A startup experiment to investigate denitrification rate with time clarified that denitrification rate of 4.35 g N/m2/day was achieved on day 10, exhibiting rapid startup for autohydrogenotrophic denitrification. Continuous denitrification experiment obviously indicated the effectiveness of the fibrous slag as a bacterial support; concretely, mean denitrification efficiency and rate after 70-days operation reached 99% and 6.58 g N/m2/day at a hydrogen pressure of 50 kPa, respectively, which results in the accomplishment of stable and high-speed denitrification. However, hydrogen utilization efficiency (HUE) was approximately 40%. This low efficiency allowed autotrophic sulfate-reducing bacteria (SRB) to grow in the fibrous-membrane matrix; eventually the HUE for sulfate reduction increased up to 28% on day 74. This result clearly indicates the significance of JH2 control through the gas-permeable membrane for suppressing the occurrence of sulfate reduction.
AB - A hydrogen-based membrane biofilm reactor (MBfR), employing fibrous slag as a bacterial carrier, was developed for rapid and stable autohydrogenotrophic denitrification. This reactor allows hydrogen to be supplied through a gas-permeable membrane to the biofilm supported by fibrous slag. The estimation of hydrogen supply rate clearly demonstrated that hydrogen flux (JH2) is dependent on the gas pressure, leading to a possibility to control JH2 by adjusting the pressure. A startup experiment to investigate denitrification rate with time clarified that denitrification rate of 4.35 g N/m2/day was achieved on day 10, exhibiting rapid startup for autohydrogenotrophic denitrification. Continuous denitrification experiment obviously indicated the effectiveness of the fibrous slag as a bacterial support; concretely, mean denitrification efficiency and rate after 70-days operation reached 99% and 6.58 g N/m2/day at a hydrogen pressure of 50 kPa, respectively, which results in the accomplishment of stable and high-speed denitrification. However, hydrogen utilization efficiency (HUE) was approximately 40%. This low efficiency allowed autotrophic sulfate-reducing bacteria (SRB) to grow in the fibrous-membrane matrix; eventually the HUE for sulfate reduction increased up to 28% on day 74. This result clearly indicates the significance of JH2 control through the gas-permeable membrane for suppressing the occurrence of sulfate reduction.
KW - Autohydrogenotrophic denitrification
KW - Biofilms
KW - Environmental preservation
KW - Hollow fibers
KW - Hydrogen utilization efficiency (HUE)
KW - Membrane biofilm reactor (MBfR)
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U2 - 10.1016/j.bej.2006.06.004
DO - 10.1016/j.bej.2006.06.004
M3 - Article
AN - SCOPUS:33747247607
VL - 31
SP - 84
EP - 91
JO - Biochemical Engineering Journal
JF - Biochemical Engineering Journal
SN - 1369-703X
IS - 1
ER -