Constructed Wetlands
Thomas More Kempen
Department
Agro- and Biotechnology
Department
Agro- and Biotechnology
Rob Van Deun
Kleinhoefstraat 4
2440 Geel
Belgium
http://www.thomasmore.be
2440 Geel
Belgium
http://www.thomasmore.be
Introduction
The spreadsheet is based on the formula's proposed by Reed, Crites, Middlebrooks, "Natural systems for waste management and treatment" (1995, McGraw-Hill, New York). This first order plug flow kinetic model incorporates flow rate, wetland depth, wetland porosity, a temperature-based rate constant and inflow and outflow concentrations. Reed et al. use volumetric temperature dependent based constants.
The Darcy formula is used to calculate the maximum flow rate.
Fill in the required data in the yellow coloured cells. If you want to clear the form, just refresh or reload the page.
A design procedure can be found in this pdf-file.
The calculations don't take into account the possible bottom slope or side slopes.
Before you start constructing, please read these lines from the "Manual Constructed Wetlands Treatment of Municipal Wastewaters", EPA, 1999, page 16:
"Misconception #1: Wetland design has been well-characterized by published design equations. Constructed wetlands are complex systems in terms of biology, hydraulics and water chemistry. Furthermore, there is a lack of quality data of sufficient detail, both temporally and spatially, on full-scale constructed wetlands. Due to the lack of data, designers have been forced to derive design parameters by aggregating performance data from a variety of wetlands, which leads to uncertainties about the validity of the parameters. ..."
The spreadsheet is based on the formula's proposed by Reed, Crites, Middlebrooks, "Natural systems for waste management and treatment" (1995, McGraw-Hill, New York). This first order plug flow kinetic model incorporates flow rate, wetland depth, wetland porosity, a temperature-based rate constant and inflow and outflow concentrations. Reed et al. use volumetric temperature dependent based constants.
The Darcy formula is used to calculate the maximum flow rate.
Fill in the required data in the yellow coloured cells. If you want to clear the form, just refresh or reload the page.
A design procedure can be found in this pdf-file.
The calculations don't take into account the possible bottom slope or side slopes.
Before you start constructing, please read these lines from the "Manual Constructed Wetlands Treatment of Municipal Wastewaters", EPA, 1999, page 16:
"Misconception #1: Wetland design has been well-characterized by published design equations. Constructed wetlands are complex systems in terms of biology, hydraulics and water chemistry. Furthermore, there is a lack of quality data of sufficient detail, both temporally and spatially, on full-scale constructed wetlands. Due to the lack of data, designers have been forced to derive design parameters by aggregating performance data from a variety of wetlands, which leads to uncertainties about the validity of the parameters. ..."