Microbiology of activated sludge treating wastewater containing Ni(II) and Cr(VI)

The species of microorganisms dominating a laboratory-scale once-through activated sludge unit treating simulated wastewater with different influent strengths (650 and 1300 mgl(-1) COD) and containing 5 to 10 mgl(-1) Ni(II) and 1 to 50 mgl(-1) Cr(VI) were identified by standard biochemical tests. Within this framework, combinations of metals and influent COD concentrations were tried. Organisms, namely Proteus rettgeri, Acinetobacter sp., Flavobacterium lutescens, Bacillus cereus var. albolactis, Klebsiella sp., Arthrobacter simplex, and Pseudomonas mendocina, were identified at different stages of the experiments. Copyright (C) 1996 IAWQ.