Assessment of long-term phosphorus retention in an integrated constructed wetland treating domestic wastewater

Dzakpasu, M; Scholz, M; McCarthy, V; Jordan, S

Abstract

Due to the nature of the phosphorus (P) removal mechanisms associated with constructed wetlands, the sustainability of P treatment is usually of high interest. As a result, a 4-year dataset from a typical multi-celled integrated constructed wetland (ICW) located at Glaslough in Co. Monaghan, Ireland was evaluated to determine the effects of long-term P loadings and hydrological inputs on P treatment. The ICW was intensively monitored year-round from February 2008 through March 2012 for total P and molybdate reactive phosphate (MRP). Domestic wastewater was loaded at 16.4 ± 0.96 g m(2) year(-1) for total P and 11.2 ± 0.74 g m(2) year(-1) for MRP. Average mass reductions over the monitoring period were 91.4 and 90.1%, respectively. The area-based kinetic coefficients (K(20)) of 11.8 for total P and 15.6 m year(-1) for MRP indicated a high area-specific retention rate. The ICW appeared to have a sustained capacity for P adsorption and retention, but the treatment was influenced mainly by external hydrological inputs and fluctuations in wastewater loadings. Linear regression analyses showed a reduction in mass retention of both total P and MRP with increased effluent flow volumes. Monthly mass reductions exceeded 90% when the effluent flow volumes were less than 200 m(3) day(-1). When monthly effluent flow volumes exceeded 200 m(3) day(-1), nonetheless, mass reductions became highly variable. Designs and management of ICW systems should adopt measures to limit external hydrological loadings in order to maintain sufficient P treatment.

Citation

Dzakpasu, M., Scholz, M., McCarthy, V., & Jordan, S. (2015). Assessment of long-term phosphorus retention in an integrated constructed wetland treating domestic wastewater. Environmental Science and Pollution Research, 22(1), 305-313. https://doi.org/10.1007/s11356-014-3350-5

• Journal Article Type: Article
• Acceptance Date: Jul 17, 2014
• Online Publication Date: Jul 27, 2014
• Publication Date: Jan 1, 2015
• Deposit Date: Mar 16, 2015
• Journal: Environmental Science and Pollution Research
• Print ISSN: 0944-1344
• Electronic ISSN: 1614-7499
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 22
• Issue: 1
• Pages: 305-313
• DOI: https://doi.org/10.1007/s11356-014-3350-5
• Publisher URL: http://dx.doi.org/10.1007/s11356-014-3350-5
• Related Public URLs: http://link.springer.com/journal/11356
• Additional Information: Funders : Funder not known