title: Effects of Lead and Mercury on Sulfate-Reducing Bacterial Activity in a Biological Process for Flue Gas Desulfurization Wastewater Treatment.
abstract: Biological sulfate-reducing bacteria (SRB) may be effective in removing toxic lead and mercury ions (Pb(II) and Hg(II)) from wet flue gas desulfurization (FGD) wastewater through anaerobic sulfite reduction. To confirm this hypothesis, a sulfite-reducing up-flow anaerobic sludge blanket reactor was set up to treat FGD wastewater at metal loading rates of 9.2 g/m(3)-d Pb(II) and 2.6 g/m(3)-d Hg(II) for 50 days. The reactor removed 72.5 ± 7% of sulfite and greater than 99.5% of both Hg(II) and Pb(II). Most of the removed lead and mercury were deposited in the sludge as HgS and PbS. The contribution of cell adsorption and organic binding to Pb(II) and Hg(II) removal was 20.0 ± 0.1% and 1.8 ± 1.0%, respectively. The different bioavailable concentration levels of lead and mercury resulted in different levels of lethal toxicity. Cell viability analysis revealed that Hg(II) was less toxic than Pb(II) to the sludge microorganisms. In the batch tests, increasing the Hg(II) feeding concentration increased sulfite reduction rates. In conclusion, a sulfite-reducing reactor can efficiently remove sulfite, Pb(II) and Hg(II) from FGD wastewater.
authors.affiliation: School of Chemistry &Environment, South China Normal University, Guangzhou, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: School of Chemistry &Environment, South China Normal University, Guangzhou, China.|SYSU-HKUST Research Center for Innovation Environmental Technology, Sun Yat-sen University, Guangzhou, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Lin
authors.affiliation: School of Chemistry &Environment, South China Normal University, Guangzhou, China.
authors.forename: Jinting
authors.initials: J
authors.lastname: Wang
authors.affiliation: School of Chemistry &Environment, South China Normal University, Guangzhou, China.|Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Guangzhou, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Jiang
authors.affiliation: Department of Civil &Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water, Kowloon, Hong Kong, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wei
authors.affiliation: Department of Civil &Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water, Kowloon, Hong Kong, China.
authors.forename: Guanghao
authors.initials: G
authors.lastname: Chen
authors.affiliation: Key Laboratory of Urban Stormwater System and Water Environment -MoU/R and D Center for Sustainable Wastewater Treatment, Beijing University of Civil Engineering and Architecture, Beijing, China.
authors.forename: Xiaodi
authors.initials: X
authors.lastname: Hao
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology; D005285:Fermentation / Q000187:drug effects; D005740:Gases / Q000737:chemistry*; D007854:Lead / Q000633:toxicity*; D008628:Mercury / Q000633:toxicity*; D050296:Microbial Viability / Q000187:drug effects; D010084:Oxidation-Reduction; D012722:Sewage / Q000382:microbiology; D013431:Sulfates / Q000378:metabolism*; D013440:Sulfides / Q000378:metabolism; D013447:Sulfites / Q000378:metabolism; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D005740:Gases; D007854:Lead; D008628:Mercury; D012722:Sewage; D013431:Sulfates; D013440:Sulfides; D013447:Sulfites; D062065:Wastewater