Performance evaluation of eight years experience of constructed wetland systems in Catalonia as alternative treatment for small communities

Effectiveness and Temporal Variation of a Full-Scale Horizontal Constructed Wetland in Reducing Nitrogen and Phosphorus from Domestic Wastewater

“…A statistical analysis of the seasonality variable has shown there was significant effect of season in TN, NH4 + -N and NOx-N removal efficiencies. In fact, we observed that autumn-winter average removal efficiencies were significantly (p < 0.05) lower for TN (0%), In a study on the performance of 11 HSSF-CWs systems in Catalonia (Spain), Vera et al [33] reported mean removal percentages for TN that are in the range of 48% and 66%, values that are consistent with the values found by Puigagut et al [34] who indicated a mean RE of 51% for TN in HSSF-CWs also in Spain. In addition, Mietto and Borin [35], when evaluating the performance of HSSF-CW treating domestic wastewater in northern Italy in the first two years of operation, obtained a TN removal efficiency of 59% for an HRT of eight days.…”

“…is recommended for eliminating organic matter and suspended solids, but is insufficient to achieve complete nitrification. However, Vera et al [33], in a study on 11 HSSF-CWs in Spain, did not find a clear and direct relationship between TN removal and the surface area. The quality of treated effluent was unstable in time and, considering the discharge requirements imposed by Portuguese Decrees Nos.…”

“…In a study based on data collected worldwide regarding the removal of P in HSSF-CWs, Vymazal [24] reported an average mass-based efficiency of 32%, while IWA [29] reported a better performance (50%) for systems operating in Europe. For 11 HSSF-CWS in Catalonia, Spain, Vera et al [33] a maximum mean of 58% for TP removal efficiency was achieved. In addition, Gagnon [49] reported a poor P removal in three wetlands where DP was the dominant P form in the inflow and found in fact the wetlands acted as net sources of P on an annual basis during establishment.…”

Seasonal Performance of Sequencing Batch Biofilm Reactors and Ecosystem Sewage Treatment Hybrid Processes in Small Towns of the Three Gorges Reservoir Area in China

“…comparing to such reports (5,7,12,23,26), our hybrid system can be considered a more effective and more economical (low cost) small-town sewage treatment technology with higher organic matter and more variation in water quality of the sewage, which was, however, inconvenient for design and management of the leachate treatment technics. Subsequent studies are needed to further optimize the hybrid system.…”

“…For example, Vera et al (23) described and characterized the performance of 11 wastewater treatment plants (WWtPs) with secondary horizontal subsurface flow (HSSF) constructed wetland systems. Hybrid systems based on an up-flow anaerobic sludge blanket (UASB) reactor have been constructed in combination with vertical and horizontal flow constructed wetlands (12) or with free water surface and subsurface flow constructed wetlands (7).…”