Ammonia Removal Processes for Urine in an Upflow Macrophyte System

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• 作者：Neda Farahbakhshazad and Gregory M. Morrison
• 刊名：Environmental Science & Technology
• 出版年：1997
• 出版时间：November 1997
• 年：1997
• 卷：31
• 期：11
• 页码：3314 - 3317
• 全文大小：93K
• 年卷期：v.31,no.11(November 1997)
• ISSN：1520-5851

文摘

Constructed wetlands represent an alternative technologyfor the removal of nitrogen from wastewater, althoughremoval mechanisms are poorly understood. Detailedstudiesof ammonia removal from diluted urine in a vertical upflowmacrophyte system were made in a column fitted withsampling ports, filled with sand, and planted with commonreed (Phragmites australis). Variations in profilesforammonia, nitrate, and dissolved oxygen were interpretedfor a range of initial ammonia concentrations andloadings.The profiles demonstrate that the previously proposedmechanism of root oxygenation promoting bacterial nitrification/denitrification may have been overemphasized. Insystems with sufficient root density and an upflow regime,luxury plant uptake with rhizome storage dominates Nremoval. Plant uptake of ammonia regulates oxygendemandand provides suitable conditions, both in terms of oxygenand ammonia concentrations, for additional bacterialnitrification. Consequently, higher concentrations andloadingrates of ammonia can be treated by an upflow macrophytesystem as compared to a bacterial systemalone.