Response of horizontal sub-surface flow constructed wetlands to sudden organic load changes

Abstract The aim of this study is to evaluate the buffering capacity of constructed wetlands by analyzing the response to sudden organic load changes. Nine horizontal flow experimental beds were divided into three equal groups and monitored in a three-phase experiment. Influent COD mass loads during Phase I were 11.4, 5.3 and 0 g/m 2 /day for Groups A–C, respectively. During Phase II there was a rise in COD mass load and Phase III restored initial conditions. Group A showed a reduction in COD removal efficiencies with mass load increase despite more intense microbiological activity. In Group B planted beds there was a reduction of the mass load removal, which could have been due to a biofilm disturbance caused by an invasive millipede species. When mass load was lowered, removal efficiencies improved. Group C showed residual effluent COD during Phase I but provided adequate removal efficiencies (75–84%) when supplied with 1.7 g/m 2 /day during Phase II. The results of this study suggest that the buffering capacity of constructed wetlands may not be enough to maintain COD removal efficiencies during a sudden organic load increase.

[1]  V. Tsihrintzis,et al.  A small-size vertical flow constructed wetland for on-site treatment of household wastewater , 2012 .

[2]  Peter A Vanrolleghem,et al.  Model-based design of horizontal subsurface flow constructed treatment wetlands: a review. , 2004, Water research.

[3]  Aracelly Caselles-Osorio,et al.  Performance of experimental horizontal subsurface flow constructed wetlands fed with dissolved or particulate organic matter. , 2006, Water research.

[4]  Laura Ortiz,et al.  Initial contaminant removal performance factors in horizontal flow reed beds used for treating urban wastewater. , 2004, Water research.

[5]  R. Haberl,et al.  Constructed wetlands in Europe , 1995 .

[6]  E. Bécares,et al.  Optimization of performance assessment and design characteristics in constructed wetlands for the removal of organic matter. , 2010, Chemosphere.

[7]  Y Comeau,et al.  Effect of loading rate on performance of constructed wetlands treating an anaerobic supernatant. , 2007, Water science and technology : a journal of the International Association on Water Pollution Research.

[8]  O. Stein,et al.  Seasonal effects of 19 plant species on COD removal in subsurface treatment wetland microcosms , 2011 .

[9]  Aracelly Caselles-Osorio,et al.  Impact of different feeding strategies and plant presence on the performance of shallow horizontal subsurface-flow constructed wetlands. , 2007, The Science of the total environment.

[10]  Rafael Mujeriego,et al.  Effect of key design parameters on the efficiency of horizontal subsurface flow constructed wetlands , 2005 .

[11]  C. Yeh,et al.  Biodiversity of constructed wetlands for wastewater treatment , 2011 .

[12]  Rafael Mujeriego,et al.  Spatial variations of temperature, redox potential, and contaminants in horizontal flow reed beds , 2003 .

[13]  Joan García,et al.  Effect of High Organic Loading Rates of Particulate and Dissolved Organic Matter on the Efficiency of Shallow Experimental Horizontal Subsurface-flow Constructed Wetlands , 2007 .

[14]  D McNevin,et al.  Indicators of biofilm development and activity in constructed wetlands microcosms. , 2004, Water research.

[15]  J. Vymazal.  Horizontal sub-surface flow and hybrid constructed wetlands systems for wastewater treatment , 2005 .

[16]  C. Campbell,et al.  Constructed Wetlands in the Sustainable Landscape , 1999 .

[17]  Weidong Zhang,et al.  Comparison of bacterial regrowth in distribution systems using free chlorine and chloramine: a statistical study of causative factors. , 2002, Water research.

[18]  A. Kivaisi.  The potential for constructed wetlands for wastewater treatment and reuse in developing countries: a review , 2001 .

[19]  A. E. Greenberg,et al.  Standard methods for the examination of water and wastewater : supplement to the sixteenth edition , 1988 .

[20]  Aracelly Caselles-Osorio,et al.  Effect of physico-chemical pretreatment on the removal efficiency of horizontal subsurface-flow constructed wetlands. , 2007, Environmental pollution.

[21]  A. O. Rangel,et al.  Treatment of industrial wastewater with two-stage constructed wetlands planted with Typha latifolia and Phragmites australis. , 2009, Bioresource technology.

[22]  Jan Vymazal,et al.  Removal of organics in constructed wetlands with horizontal sub-surface flow: a review of the field experience. , 2009, The Science of the total environment.

[23]  F. Masi,et al.  Tolerance to hydraulic and organic load fluctuations in constructed wetlands. , 2007, Water science and technology : a journal of the International Association on Water Pollution Research.

[24]  Scott Wallace,et al.  Small Scale Constructed Wetland Treatment Systems: Feasibility, Design Criteria and O&m Requirements , 2006 .

[25]  M. L. Solano,et al.  Constructed Wetlands as a Sustainable Solution for Wastewater Treatment in Small Villages , 2004 .

[26]  S. Terzakis,et al.  Pilot-scale comparison of constructed wetlands operated under high hydraulic loading rates and attached biofilm reactors for domestic wastewater treatment. , 2009, The Science of the total environment.

[27]  P. Huck,et al.  Measurement of biomass activity in drinking water biofilters using a respirometric method. , 2001, Water research.

[28]  Vassilios A. Tsihrintzis,et al.  Effect of temperature, HRT, vegetation and porous media on removal efficiency of pilot-scale horizontal subsurface flow constructed wetlands , 2007 .

[29]  Maarten W. Saaltink,et al.  Evaluation of relative importance of different microbial reactions on organic matter removal in horizontal subsurface-flow constructed wetlands using a 2D simulation model , 2008 .

[30]  Raimund Haberl,et al.  Constructed wetlands for the treatment of organic pollutants , 2003 .