Effect of arsenic on nitrification of simulated mining water.
Mining and mineral processing of gold-bearing ores often release arsenic to the environment. Ammonium is released when N-based explosives or cyanide are used. Nitrification of simulated As-rich mining waters was investigated in batch bioassays using nitrifying cultures enriched in a fluidized-bed reactor (FBR). Nitrification was maintained at 100mg AsTOT/L. In batch assays, ammonium was totally oxidized by the FBR enrichment in 48 h. As(III) oxidation to As(V) occurred during the first 3h attenuating arsenic toxicity to nitrification. At 150 and 200mg AsTOT/L, nitrification was inhibited by 25%. Candidatus Nitrospira defluvii and other nitrifying species mainly colonized the FBR. In conclusion, the FBR enriched cultures of municipal activated sludge origins tolerated high As concentrations making nitrification a potent process for mining water treatment.
Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FIN-33101 Tampere, Finland. Electronic address: stefano.papirio@tut.fi.
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Papirio
Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FIN-33101 Tampere, Finland.
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Zou
Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FIN-33101 Tampere, Finland.
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Ylinen
Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FIN-33101 Tampere, Finland; Department of Civil, Architectural and Environmental Engineering, University of Napoli "Federico II", 80125 Napoli, Italy.
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Di Capua
Department of Civil, Architectural and Environmental Engineering, University of Napoli "Federico II", 80125 Napoli, Italy.
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Pirozzi
Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FIN-33101 Tampere, Finland.
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Puhakka
D000468:Alkalies / Q000032:analysis; D064751:Ammonium Compounds / Q000032:analysis; D001151:Arsenic / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000378:metabolism; D061249:Batch Cell Culture Techniques; D001681:Biological Assay; D019149:Bioreactors / Q000382:microbiology; D058645:Denaturing Gradient Gel Electrophoresis; D006863:Hydrogen-Ion Concentration; D008906:Mining; D009566:Nitrates / Q000032:analysis; D058465:Nitrification / Q000187:drug effects*; D009573:Nitrites / Q000032:analysis; D062065:Wastewater / Q000737:chemistry*
D000468:Alkalies; D064751:Ammonium Compounds; D001151:Arsenic; D009566:Nitrates; D009573:Nitrites; D062065:Wastewater
Ammonium; Arsenic; Mining; Nitrification; Nitrifying microbial communities