Roles of oyster shells in an integrated constructed wetland system designed for P removal

This paper investigates the potential for constructed Melaleuca wetlands to provide buffering for sewage spills. The experimental site was a 4.5 m × 32 m surface flow constructed wetland planted with the tree species M. quinquenervia and M. alternifolia. Primary settled sewage was discharged into the wetland at flow rates of 300 and 600 lh−1, and the concentrations of commonly measured sewage pollutants were monitored at the inlet, middle, and outlet. The constructed wetland was an excellent sediment trap, with TSS removals of up to 98%. BOD5 and turbidity had correspondingly high removals of up to 93% and 97% respectively. At both flow rates there were was 100% reduction in faecal coliform. Nitrogen removal was dependent on the flow rate, with removals of 84% and 58% at 300 and 600 lh−1 respectively. Organic P removal was high, however the wetland system was a source of PO4-P. A conceptual model is presented for a constructed Melaleuca wetland designed for tea tree oil production, effluent polishing and emergency buffering for sewage spills.

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Integrated constructed wetland systems employing alum sludge and oyster shells as filter media for P removal

Ecological Engineering ◽

10.1016/j.ecoleng.2009.05.015 ◽

2009 ◽

Vol 35 (8) ◽

pp. 1275-1282 ◽

Cited By ~ 33

Author(s):

W.H. Park

Keyword(s):

Constructed Wetland ◽

Filter Media ◽

Integrated Constructed Wetland ◽

Alum Sludge ◽

P Removal

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Integrated Constructed Wetland (ICW) System a Sustainable Novel Technique for Urban Wastewater Management

10.21203/rs.3.rs-560094/v1 ◽

2021 ◽

Author(s):

Jeyaraman Sethuraman Sudarsan ◽

Ramasamy Annadurai ◽

Subramanian Nithiyanantham

Keyword(s):

Constructed Wetland ◽

Typha Latifolia ◽

Oxygen Demand ◽

Impurity Level ◽

Wastewater Management ◽

System A ◽

Reduction Efficiency ◽

Integrated Constructed Wetland ◽

Wetland System ◽

One Year

Abstract The present study focuses on various aspects of Integrated Constructed Wetland System (ICW) systems with reference to its efficiency, and eco-friendliness in the treatment of domesticwastewater. The biological oxygen demand (BOD) impurity level is in the ranged from 383 mgl-1 to 248 mgl-1, chemical oxygen demand (COD)420 mgl-1 to 340 mgl-1, Total Phosphorus (TP) 10.2 mgl-1 to 5 mgl-1 and Total Nitrogen (TN) 18.9 mgl-1 to 14.8 mgl-1 respectively over a period of one year (SRM University). The influent contaminants are degradable in nature especially with high TP and TN concentrations. Six units of Constructed Wetland System (ICW)units are built with uniform dimensions of 2×1× 0.9 m based on EPA and TVA.The wetland plants chosen areTypha Latifolia and Phragmites Australis. Among the wetland units, Typha oriented units are observed to perform better with a reduction efficiency of 87% for BOD, 86% for COD, 70% for TP and 78% for TN proving that Typha Latifoliais a better aquatic plant for overall wastewater treatment. The removal efficiency increases with time and reaches maximum in 192 hrs. To substantiate the experimental study output, Statistical analysis (ANOVA) and multiple regression analysis with normality plot has carried out. It isevident that thepercentage removal of many parameters especially organic parameters over a period of time in treating with different wetland units is highly significant.

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Enhanced P, N and C removal from domestic wastewater using constructed wetland employing construction solid waste (CSW) as main substrate

Water Science & Technology ◽

10.2166/wst.2012.277 ◽

2012 ◽

Vol 66 (5) ◽

pp. 1022-1028 ◽

Cited By ~ 14

Author(s):

Y. Yang ◽

Z. M. Wang ◽

C. Liu ◽

X. C. Guo

Keyword(s):

Organic Matter ◽

Solid Waste ◽

Constructed Wetland ◽

Tidal Flow ◽

Domestic Wastewater ◽

Treatment System ◽

Ammoniacal Nitrogen ◽

Wetland System ◽

Main Substrate ◽

P Removal

Construction solid waste (CSW), an inescapable by-product of the construction and demolition process, was used as main substrate in a four-stage vertical subsurface flow constructed wetland system to improve phosphorus P removal from domestic wastewater. A ‘tidal flow’ operation was also employed in the treatment system. Under a hydraulic loading rate (HLR) of 0.76 m3/m2 d for 1st and 3rd stage and HLR of 0.04 m3/m2 d for 2nd and 4th stage of the constructed wetland system respectively and tidal flow operation strategy, average removal efficiencies of 99.4% for P, 95.4% for ammoniacal-nitrogen, 56.5% for total nitrogen and 84.5% for total chemical oxygen demand were achieved during the operation period. The CSW-based constructed wetland system presents excellent P removal performance. The adoption of tidal flow strategy creates the aerobic/anoxic condition intermittently in the treatment system. This can achieve better oxygen transfer and hence lead to more complete nitrification and organic matter removal and enhanced denitrification. Overall, the CSW-based tidal flow constructed wetland system holds great promise for enabling high rate removal of P, ammoniacal-nitrogen and organic matter from domestic wastewater, and transforms CSW from a waste into a useful material.

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