Abstract

In the present study, the bioremoval of Cr(VI) and the removal of total organic carbon (TOC) were achieved with a system composed by an anaerobic filter and a submerged biofilter with intermittent aeration using a mixed culture of microorganisms originating from contaminated sludge. In the aforementioned biofilters, the concentrations of chromium, carbon, and nitrogen were optimized according to response surface methodology. The initial concentration of Cr(VI) was 137.35 mg l(-1), and a bioremoval of 85.23% was attained. The optimal conditions for the removal of TOC were 4 to 8 g l(-1) of sodium acetate, >0.8 g l(-1) of ammonium chloride and 60 to 100 mg l(-1) of Cr(VI). The results revealed that ammonium chloride had the strongest effect on the TOC removal, and 120 mg l(-1) of Cr(VI) could be removed after 156 h of operation. Moreover, 100% of the Cr(VI) and the total chromium content of the aerobic reactor output were removed, and TOC removals of 80 and 87% were attained after operating the anaerobic and aerobic reactors for 130 and 142 h, respectively. The concentrations of cells in both reactors remained nearly constant over time. The residence time distribution was obtained to evaluate the flow through the bioreactors.

Links

Publisher Full Text

Authors

Leles DM, Lemos DA, Filho UC, Romanielo LL, de Resende MM, Cardoso VL

Institution

Faculty of Chemical Engineering, Uberlândia Federal University, P.O. Box 593, Av. João Naves de Ávila, 2121, Campus Santa Mônica, Bloco 1K, Uberlândia, MG, 38408-100, Brazil.

Source

Biodegradation 23:3 2012 Jun pg 441-54

MeSH

Bacteria
Biodegradation, Environmental
Bioreactors
Carbon
Chromium
Environmental Remediation
Kinetics
Micropore Filters
Sewage

Pub Type(s)

Evaluation Studies
Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

22119895