Effect of hydraulic retention time on lactic acid production and granulation in an up-flow anaerobic sludge blanket reactor.
In the present work, lactic acid (LA) production performance with granulation was investigated at various hydraulic retention times (HRTs), 8-0.5h. Glucose was used as a feedstock, and anaerobic mixed cultures were inoculated in an up-flow anaerobic sludge blanket reactor. As HRT decreased, the average diameter and hydrophobicity of the granules increased from 0.31 to 3.4mm and from 17.5% to 38.3%, respectively, suggesting the successful formation of granules. With decreasing HRT, LA productivity increased up to 16.7gLA/L-fermenter/h at HRT 0.5h. The existence of rod-shaped organisms with pores and internal channels at granule surface was observed by scanning electron microscope. Next generation sequencing revealed that Lactobacillus was the dominant microorganism, accounting for 96.7% of total sequences, comprising LA-producing granules.
Biomass and Waste Energy Laboratory, Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343, Republic of Korea.
Dong-Hoon
DH
Kim
Biomass and Waste Energy Laboratory, Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343, Republic of Korea.
Mo-Kwon
MK
Lee
Biomass and Waste Energy Laboratory, Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343, Republic of Korea.
Chungman
C
Moon
Department of Civil and Environmental Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
Yeo-Myeong
YM
Yun
School of Civil and Environmental Engineering, Kumoh National Institute of Technology, 1 Yangho-dong, Gumi, Gyeongbuk 730-701, Republic of Korea.
Wontae
W
Lee
Department of Environmental Engineering, Hanbat National University, San 16-1, Duckmyoung-dong, Yuseong-gu, Daejeon, Republic of Korea.
Sae-Eun
SE
Oh
Biomass and Waste Energy Laboratory, Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343, Republic of Korea; Division of Renewable Energy Engineering, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 305-350, Republic of Korea. Electronic address: bmmskim@kier.re.kr.
Mi-Sun
MS
Kim
D000693:Anaerobiosis; D001419:Bacteria / Q000378:metabolism; D019149:Bioreactors / Q000382:microbiology*; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D019344:Lactic Acid / Q000096:biosynthesis*; D010316:Particle Size; D012212:Rheology; D012722:Sewage / Q000382:microbiology*; D013045:Species Specificity; D013997:Time Factors
D012722:Sewage; D019344:Lactic Acid
Granulation; Hydraulic retention time (HRT); Hydrophobicity; Lactic acid; Up-flow anaerobic sludge blanket reactor (UASBr)