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Use of constructed wetland for the removal of heavy metals from industrial wastewater 总被引:4,自引:0,他引:4
Sardar Khan Irshad Ahmad M. Tahir Shah Shafiqur Rehman Abdul Khaliq 《Journal of environmental management》2009,90(11):3451-3457
This study was conducted to investigate the effectiveness of a continuous free surface flow wetland for removal of heavy metals from industrial wastewater, in Gadoon Amazai Industrial Estate (GAIE), Swabi, Pakistan. Industrial wastewater samples were collected from the in-let, out-let and all cells of the constructed wetland (CW) and analyzed for heavy metals such as lead (Pb), cadmium (Cd), iron (Fe), nickel (Ni), chromium (Cr) and copper (Cu) using standard methods. Similarly, samples of aquatic macrophytes and sediments were also analyzed for selected heavy metals. Results indicate that the removal efficiencies of the CW for Pb, Cd, Fe, Ni, Cr, and Cu were 50%, 91.9%, 74.1%, 40.9%, 89%, and 48.3%, respectively. Furthermore, the performance of the CW was efficient enough to remove the heavy metals, particularly Cd, Fe, and Cu, from the industrial wastewater fed to it. However, it is suggested that the metal removal efficiency of the CW can be further enhanced by using proper management of vegetation and area expansion of the present CW. 相似文献
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Use of cattails in treating wastewater from a Pb/Zn mine 总被引:2,自引:0,他引:2
This article describes the use of a combined treatment system, which includes an aquatic treatment pond withTypha latifolia Linn. (Typhaceae) as the dominant species and a stabilization pond, to treat the wastewater from a Pn/Zn mine at Shaoguan,
Guangdong Province, China.
In 1983, it was noted thatT. latifolia bloomed in areas affected by the wastewater emitted from the mine, hence a combined purification system was subsequently
built.
The influent contained high levels of total suspended solids (4635 mg/liter), chemical oxygen demand (14.5 mg/liter) as well
as Pb (1.6 mg/liter) and Zn (1.9 mg/liter). The results of the effluent after treatment showed that the total suspended solids,
chemical oxygen demand, Pb, and Zn had been reduced by 99%, 55%, 95%, and 80% respectively. The results of plant tissue analysis
indicled thatT. latifolia assimilated significant amounts of Pb and Zn, especially in the root portion.
During 1986 several species of algae and fish were present in the pond, usually with a higher density in areas containing
lower metal concentrations in the water.
Paper was presented in part at the conference “The Use of Constructed Wetlands in Water Pollution Control” held 24–28 September
1990, Cambridge, UK. 相似文献
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There is an increasing need for the accurate delineation of wetlands for planning and conservation purposes. We propose a method based on vegetation zonation which requires three steps. The first step is to examine transects crossing the transition zone from marsh to upland. In each transect the uppermost occurrence of each plant species is located relative to a fixed survey point. The second step is to determine which of these species are hydrophytes (wetland plants). This is assessed using the presence or absence of morphological and physiological adaptations for growing in wet environments. Alternatively, a literature search using botanical manuals may suffice. The third step determines the upper limit of the wetland by finding the upper limit of the uppermost hydrophyte in each transect, and taking the mean value of these over all transects. This mean defines the boundary of the wetland. The method is illustrated using two marshes along the north shore of the St. Lawrence River in Ontario. 相似文献
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