期刊名称:Universal Journal of Environmental Research and Technology
电子版ISSN:2249-0256
出版年度:2011
卷号:1
期号:3
出版社:Euresian Publications
摘要:Constructed wetlands are considered as low cost treatment option for domestic and industrial wastewater in the recent decades. The presence of toxic heavy metals in wastewater is a problematic issue, since these heavy metals have potential to accumulate in the treatment systems. Thus heavy metals greatly influence the efficiency of constructed wetlands. Therefore a feasibility study was proposed for long term usage of constructed wetlands as treatment systems. Initially sediment in a constructed wetland was contaminated with simulated nickel containing groundwater followed by using suitable leaching solution to rejuvenate the heavy metal contaminated sediment. A batch study was performed to identify the optimum pH for nickel adsorption on sand. The efficiency of different leaching solutions to remove the adsorbed nickel from sand was studied. Following this a Pilot scale study was carried out in constructed wetland treatment plant (vertical flow) at Anna University, Chennai, India. The amount of nickel solution charged into the Control Cell (sand) and Test Cell (sand planted with Arundo donax) was 29000 mg/cell. The concentration of nickel adsorbed to sand increased from 0.2mg/Kg to 4.34 mg/Kg in the control cell whereas the increase in test cell was 4.08mg/Kg. Leaching the wetland with EDTA solution resulted in removal of nickel up to its background concentrations on the sand. It can be concluded that the proposed feasibility study can be used to rejuvenate the sediment in a constructed wetland for its long term usage as treatment systems