Kinetics of Fecal Coliform Removal in Constructed Wetlands Available to Purchase

Major mechanisms influencing the removal of fecal microorganisms in constructed wetlands treating sewage in tropical regions include the effects of temperature, solar radiation, sedimentation, adsorption and filtration. This study aims to develop a model describing the kinetics of fecal coliform removal in free-water-surface (FWS) constructed wetlands. Separate model equations were proposed for removal rate coefficients for each of the major removal mechanisms. The model parameters were assessed from both literature and the performance data of laboratory-scale FWS constructed wetland units planted with cattails (Typha angustifolia). The model parameters and the kinetic model were validated with experimental data of two pilot-scale constructed wetlands. Statistical analyses of the calculated and observed performance data of the pilot-scale units revealed good correlation and were without significant practical difference, suggesting the kinetic model was feasible.