Purification ability and carbon dioxide flux from surface flow constructed wetlands treating sewage treatment plant effluent

Subsurface Flow Constructed Wetlands for Wastewater Treatment

Design and Season Influence Nitrogen Dynamics in Two Surface Flow Constructed Wetlands Treating Nursery Irrigation Runoff

Constructed wetlands (CWs) are used to remediate runoff from a variety of agricultural, industrial, and urban sources. CW remediation performance is often evaluated at the laboratory scale over durations less than one year. The purpose of this study was to characterize the effect of CW design (cell depth) and residence time on nitrogen (N) speciation and fate across season and years in two free...

Removal of nutrients from septic tank effluent with baffle subsurface-flow constructed wetlands.

Three new baffle flow constructed wetlands (CWs), namely the baffle horizontal flow CW (Z1), baffle vertical flow CW (Z2) and baffle hybrid flow CW (Z3), along with one traditional horizontal subsurface flow CW (Z4) were designed to test the removal efficiency of nitrogen (N) and phosphorus (P) from the septic tank effluent under varying hydraulic retention times (HRTs). Results showed that the...

Nitrifyers in constructed wetlands treating landfill leachates

Landfill leachate is produced many years after a landfill site closes. Hence, treatment by “natural methods”, as e.g. constructed wetlands, with low management requirements is attractive. Constructed wetlands usually provide both shallow and deep areas with aerobic and anaerobic zones, which is suitable for nitrification followed by denitrification of the ammonium-rich leachates. Full-scale tre...

Recirculating Vertical Flow Constructed Wetlands

In parts of the United States where soils are very permeable, conventional septic tank and absorption field systems are considered the largest contributor to waterborne disease and pollution of water bodies. However, an economical, recirculating vertical flow (RVF) constructed wetland, used as a pretreatment system, can significantly improve the performance of conventional onsite wastewater tre...