Phosphorus retention and mass balance in an integrated constructed wetland treating domestic wastewater

This research was conducted to investigate the phosphorus forms present in water, soil and sediment and to estimate the phosphorus mass balance in a surface flow constructed wetland (CW). Water quality and sediment samples were collected from each cell along the hydrologic path in the CW from October 2008 to December 2010. At the same time, three dominant plant species (e.g. common reed and cattails) were observed through the measurement of the weight, height and phosphorus content. Based on the results, the orthophosphate constituted 24–34% of total phosphorus in water for each cell. The overall average phosphorus removal efficiency of the CW was approximately 38%. The average inflow and outflow phosphorus loads during the monitoring period were 1,167 kg/yr and 408 kg/yr, respectively. The average phosphorus retention rate was 65%, was mainly contributed by the settling of TP into the bottom sediments (30%). The phosphorus uptake of plants was less than 1%. The estimated phosphorus mass balance was effective in predicting the phosphorus retention and release in the CW treating wastewater. Continuous monitoring is underway to support further assessment of the CW system and design.

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Nitrogen removal in an integrated constructed wetland treating domestic wastewater

Journal of Environmental Science and Health Part A ◽

10.1080/10934529.2011.571592 ◽

2011 ◽

Vol 46 (7) ◽

pp. 742-750 ◽

Cited By ~ 13

Author(s):

Mawuli Dzakpasu ◽

Oliver Hofmann ◽

Miklas Scholz ◽

Rory Harrington ◽

Siobhan N. Jordan ◽

...

Keyword(s):

Nitrogen Removal ◽

Constructed Wetland ◽

Domestic Wastewater ◽

Integrated Constructed Wetland

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Nitrogen transformations and mass balance in an integrated constructed wetland treating domestic wastewater

Water Science & Technology ◽

10.2166/wst.2014.402 ◽

2014 ◽

Vol 70 (9) ◽

pp. 1496-1502 ◽

Cited By ~ 8

Author(s):

Mawuli Dzakpasu ◽

Miklas Scholz ◽

Valerie McCarthy ◽

Siobhán Jordan

Keyword(s):

Mass Balance ◽

Domestic Wastewater ◽

Nitrogen Transformations ◽

Sediment Storage ◽

N Transformations ◽

Total N ◽

N Removal ◽

Load Removal ◽

Integrated Constructed Wetland ◽

Complete Average

Nitrogen (N) transformations and removal in integrated constructed wetlands (ICWs) are often high, but the contributions of various pathways, including nitrification/denitrification, assimilation by plants and sediment storage, remain unclear. This study quantified the contributions of different N removal pathways in a typical multi-celled ICW system treating domestic wastewater. Findings showed near complete average total N retention of circa 95% at 102.3 g m−2 yr−1 during the 4-year period of operation. Variations in total N and NH4–N removal rates were associated with effluent flow volume rates and seasons. According to the mass balance estimation, assimilation by plants and sediment/soil storage accounted for approximately 23% and 20%, respectively, of the total N load removal. These were the major N removal route besides microbial transformations. Thus, the combination of plants with high biomass production offer valuable opportunities for improving ICW performance. The retrieval and use of sequestered N in the ICW sediment/soils require coherent management and provide innovative and valuable opportunities.

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Treatment of Combined Dairy and Domestic Wastewater with Constructed Wetland System in Sicily (Italy). Pollutant Removal Efficiency and Effect of Vegetation

Water ◽

10.3390/w13081086 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1086

Author(s):

Mario Licata ◽

Roberto Ruggeri ◽

Nicolò Iacuzzi ◽

Giuseppe Virga ◽

Davide Farruggia ◽

...

Keyword(s):

Plant Growth ◽

Organic Compounds ◽

Removal Efficiency ◽

Constructed Wetland ◽

Organic Pollutant ◽

Dairy Farm ◽

Domestic Wastewater ◽

Pollutant Removal ◽

Dairy Wastewater ◽

Giant Reed

Dairy wastewater (DWW) contains large amounts of mineral and organic compounds, which can accumulate in soil and water causing serious environmental pollution. A constructed wetland (CW) is a sustainable technology for the treatment of DWW in small-medium sized farms. This paper reports a two-year study on the performance of a pilot-scale horizontal subsurface flow system for DWW treatment in Sicily (Italy). The CW system covered a total surface area of 100 m2 and treated approximately 6 m3 per day of wastewater produced by a small dairy farm, subsequent to biological treatment. Removal efficiency (RE) of the system was calculated. The biomass production of two emergent macrophytes was determined and the effect of plant growth on organic pollutant RE was recorded. All DWW parameters showed significant differences between inlet and outlet. For BOD5 and COD, RE values were 76.00% and 62.00%, respectively. RE for total nitrogen (50.70%) was lower than that of organic compounds. RE levels of microbiological parameters were found to be higher than 80.00%. Giant reed produced greater biomass than umbrella sedge. A seasonal variation in RE of organic pollutants was recorded due to plant growth rate Our findings highlight the efficient use of a CW system for DWW treatment in dairy-cattle farms.

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