Inhibition and recovery in a fixed microbial film leachate treatment system subject to shock loading of copper and zinc.
The impacts of shock loadings of copper and zinc (up to 50 mg l(-1)) on the treatment efficiency of a mesoscale-fixed microbial film landfill leachate treatment system were investigated. Treatment inhibition and recovery were monitored in sequence over two 36 h experimental runs. The fate of added metals was also investigated. Copper, and to a lesser extent zinc, added to the treatment systems accumulated on the biofilm media. Increasing copper inputs (>10 mg l(-1)) progressively inhibited biological treatment of ammoniacal-nitrogen and carbon; this inhibition persisted into the recovery phase for nitrogen but not for carbon. Only the highest input of zinc affected media metal contents and carbon treatment rates; the latter inhibitory effect did not persist into the recovery phase. A small proportion of the metals accumulated on the biofilm media during the inhibition phase was released into the bulk leachate during the recovery experiment. These findings suggest a need to manage metal inputs into leachate treatment systems in order to ensure their continued efficacy.
Scullion
John
J
Institute of Biological Sciences, University of Wales, Penglais, Aberystwyth SY23 3DA, UK. jos@aber.ac.uk
Winson
Michael
M
Matthews
Richard
R
D018441:Biofilms; D003300:Copper / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
D014874:Water Pollutants, Chemical; D003300:Copper; D015032:Zinc