Bio-immobilization of Cu and Zn in recirculated bioreactor landfill.
OBJECTIVE
To protect the environmental quality of soil, groundwater, and surface water near the landfill site, it is necessary to make an accurate assessment of the heavy metal mobility. This study aims to present the bio-immobilization behavior of heavy metals in landfill and provide some reference suggestion for the manipulation of heavy metal pollution control after closure.


METHODS
Two simulated bioreactor landfill system loaded with real municipal solid waste (MSW), namely, conventional bioreactor landfill (CL) and leachate recirculated bioreactor landfill (RL), were operated. Cu and Zn, the two conventional heavy metals with the highest contents in MSW, were chosen to track the heavy metal bio-immobilization behavior in landfill.


RESULTS
The MSW in landfill is a great threat to environment because much of the heavy metal is "hidden" in different components. The weight ratio of Cu and Zn in landfill amounts to 0.00427% and 0.00437%, respectively. The accumulated effluent masses of Cu and Zn in CL increased all along, while they still kept at a stable level after day 105 in RL.


CONCLUSIONS
The microbes like sulfate-reducing bacteria mediate the behavior of Cu and Zn in bioreactor landfill system. Cu and Zn can be bio-immobilized in bioreactor landfill system with leachate recirculation like RL.
Long
Yu-Yang
YY
Department of Environmental Engineering, Zhejiang University, Hangzhou 310029, China.
Hu
Li-Fang
LF
Wang
Jing
J
Fang
Cheng-Ran
CR
He
Ruo
R
Shen
Dong-Sheng
DS
D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D003300:Copper / Q000032:analysis / Q000378:metabolism*; D004785:Environmental Pollutants / Q000032:analysis / Q000378:metabolism*; D012037:Refuse Disposal / Q000379:methods*; D015032:Zinc / Q000032:analysis / Q000378:metabolism*
D004785:Environmental Pollutants; D003300:Copper; D015032:Zinc