TY - JOUR
T1 - Continuous hydrogen production by anaerobic mixed microflora using a hollow-fiber microfiltration membrane bioreactor
AU - Lee, Kuo Shing
AU - Lin, Ping Jei
AU - Fangchiang, Kai
AU - Chang, Jo Shu
N1 - Funding Information:
The authors gratefully acknowledge the financial support of the National Science Council, Taiwan (Grant Nos. NSC91-2815-C-035-013-E, NSC92-2214-E-035-007, and NSC94-2211-E-166-008) and the Bureau of Energy, Ministry of Economic Affairs, Taiwan (Grant Nos. NSC93-ET-7-006-001-ET, NSC94-ET-7-006-004-ET, 94-D0137-2, and 95-D0137-2). We also thank Mr. L.-H. Yang for their assistance on bioreactor operations.
PY - 2007/6
Y1 - 2007/6
N2 - A membrane bioreactor (MBR) fabricated by connecting a hollow-fiber microfiltration membrane module with a continuous flow stirred tank reactor (CSTR) was used to enhance H2 production through high-dilution rate operations. Three different carbon substrates (glucose, sucrose, and fructose) were examined for their effectiveness in H2 production with a mixed microflora. The results show that in CSTR operation, cell washout occurred at a hydraulic retention time (HRT) of 2-4 h. Using MBR could avoid cell washout, leading to a substantial increase in both H2 production rate (HPR) and biomass concentration. The MBR system was very effective in retaining biomass within the reactor as the system can be stably operated at an extremely low HRT of 1 h with an optimal steady-state HPR of 1.48, 2.07, and 2.75 l/h/l, respectively, for using glucose, sucrose, and fructose as the sole carbon source. Meanwhile, despite operation at a high dilution rate (i.e., HRT = 1 h), the H2 yield (HY) could be maintained at a high level of 1.27, 1.39, and 1.36 mol H2 / mol hexose, for glucose, sucrose, and fructose, respectively. Irrespective of the bioreactor mode (CSTR or MBR), the HPR tended to decrease in the order of fructose > sucrose > glucose. Thus, fructose seems to be the most efficient carbon substrate for H2 production with the H2-producing mixed culture used in this work. Butyrate (HBu) and acetate (HAc) (especially, HBu) were the major soluble metabolites in all cases, contributing to 70-85% of total soluble microbial product (SMP). The HPR and HY could be estimated based on stoichiometric correlation between formation of soluble metabolites (i.e., HBu, HAc, and propionate) and H2 production. The estimated values are in good agreement with the experimental results.
AB - A membrane bioreactor (MBR) fabricated by connecting a hollow-fiber microfiltration membrane module with a continuous flow stirred tank reactor (CSTR) was used to enhance H2 production through high-dilution rate operations. Three different carbon substrates (glucose, sucrose, and fructose) were examined for their effectiveness in H2 production with a mixed microflora. The results show that in CSTR operation, cell washout occurred at a hydraulic retention time (HRT) of 2-4 h. Using MBR could avoid cell washout, leading to a substantial increase in both H2 production rate (HPR) and biomass concentration. The MBR system was very effective in retaining biomass within the reactor as the system can be stably operated at an extremely low HRT of 1 h with an optimal steady-state HPR of 1.48, 2.07, and 2.75 l/h/l, respectively, for using glucose, sucrose, and fructose as the sole carbon source. Meanwhile, despite operation at a high dilution rate (i.e., HRT = 1 h), the H2 yield (HY) could be maintained at a high level of 1.27, 1.39, and 1.36 mol H2 / mol hexose, for glucose, sucrose, and fructose, respectively. Irrespective of the bioreactor mode (CSTR or MBR), the HPR tended to decrease in the order of fructose > sucrose > glucose. Thus, fructose seems to be the most efficient carbon substrate for H2 production with the H2-producing mixed culture used in this work. Butyrate (HBu) and acetate (HAc) (especially, HBu) were the major soluble metabolites in all cases, contributing to 70-85% of total soluble microbial product (SMP). The HPR and HY could be estimated based on stoichiometric correlation between formation of soluble metabolites (i.e., HBu, HAc, and propionate) and H2 production. The estimated values are in good agreement with the experimental results.
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U2 - 10.1016/j.ijhydene.2006.09.018
DO - 10.1016/j.ijhydene.2006.09.018
M3 - Article
AN - SCOPUS:34248637608
SN - 0360-3199
VL - 32
SP - 950
EP - 957
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
IS - 8
ER -