Performance of a haloalkaliphilic bioreactor and bacterial community shifts under different COD/SO₄²⁻ ratios and hydraulic retention times.
Sulfur dioxide from flue gas was converted into sulfate after the absorption of alkaline solutions. Haloalkaliphilic microorganisms have been used in reducing sulfate to decrease expenses and avoid sulfide inhibition. The effects of different COD/SO4(2-) ratios and hydraulic retention times (HRTs) on the sulfate removal efficiency and bacterial community were investigated in model experiments. Ethanol showed better performance as an electron donor than lactate. The optimum COD/SO4(2-) ratio and HRT were 4.0 and 18 h, respectively, with respective sulfate removal efficiency and rate of 97.8 ± 1.11% and 6.26 ± 0.0710 g/Ld. Sulfide concentrations reached 1,603 ± 3.38 mg/L. Based on denaturing gradient gel electrophoresis analysis of 16S rDNA, the major sulfate-reducing bacterium (SRB) was Desulfonatronovibrio sp., which was only detected at a COD/SO4(2-) ratio of 4.0 using ethanol as an electron donor. Different HRTs had no significant effect on the band corresponding to this species. PCR results show that methane-producing archaea (MPA) were from the acetoclastic methanogenic family Methanosarcinaceae. Quantitative real-time PCR did not demonstrate any significant competition between SRB and MPA. The findings of this study indicate that sulfate reduction, nitrate reduction, and sulfide oxidization may occur in the same bioreactor.
National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, PO Box 353, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Jie-Min
JM
Zhou
National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, PO Box 353, Beijing 100190, PR China.
Zi-Yu
ZY
Song
National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, PO Box 353, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Dao-Jiang
DJ
Yan
National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, PO Box 353, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Yi-Lan
YL
Liu
National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, PO Box 353, Beijing 100190, PR China.
Mao-Hua
MH
Yang
National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, PO Box 353, Beijing 100190, PR China.
Hong-Bin
HB
Cao
National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, PO Box 353, Beijing 100190, PR China. Electronic address: jmxing@home.ipe.ac.cn.
Jian-Min
JM
Xing
D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D019641:DNA, Archaeal / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal; D017019:Methanosarcinaceae / Q000235:genetics / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism; D013431:Sulfates / Q000378:metabolism*; D013440:Sulfides / Q000378:metabolism
D019641:DNA, Archaeal; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D009566:Nitrates; D013431:Sulfates; D013440:Sulfides
DGGE; Haloalkaliphilic; Methane-producing archaea; Sulfate-reducing bacteria; Sulfur-oxidizing bacteria