A Comparative Study of Five Up-flow Constructed Wetlands with Different Designs and Plant Species for Industrial Wastewater Treatment

摘要

Combination of anaerobic and aerobic processes could enhance the performance of constructed wetland in treating wastewater containing nutrients and less-biodegradable organic pollutants. The objective of present study was to assess the simultaneous removal of organic pollutants and nutrients by five laboratory scale up-flow constructed wetlands (UFCWs) with and without supplementary aeration, and with different emergent plants. The emergent plants employed were Phragmites australis and Manchurian wild rice. The ORP and DO profile along the wetland bed showed the anaerobic and aerobic regions were well developed at the lower and upper bed,respectively, in the aerated wetland reactors. The COD, T-N, T-P, ammonium-N and nitrate removal efficiencies for UFCWs were in the range of 90 94, 73 92, 29 52, 59 98 and 45 100 %, respectively. The aerated wetland reactors outperformed the non-aerated wetland reactors in terms of organic matter and ammonium-N removal. The Manchurian wild rice performed better in the removals of T-N and T-P compared to the Phragmites australis. The high treatment performance shows the high applicability of this system for simultaneous removal of nutrients and less-biodegradable organic pollutants in industrial wastewater.