Author/Authors :
Farzadkia، Mahdi نويسنده Associate Professor, Department of Environmental Health Engineering , , Ehrampush، Mohammad Hassan نويسنده Department of Environmental Health Engineering, School of Public Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran , , Abouee Mehrizi، Ehsan نويسنده Environment Research Center, Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, and Department of Environmental Health Engineering, Faculty of Public Health, North Khorasan University of Medical Sciences, Bojnurd, Iran , , sadeghi، shahram نويسنده , , Talebi Hematabadi، Parvaneh نويسنده Department of Environmental Engineering, Meybod Branch, Islamic Azad University , Yazd, IR Iran , , Salehi Vaziri، Akbar نويسنده Department of Environmental Engineering, Meybod Branch, Islamic Azad University , Yazd, IR Iran , , Kermani، Majid نويسنده ,
Abstract :
Background: Investigating the performance of naturally operated treatment plants may be due to the fact that they cannot be operated as desired, or that they should be modified to achieve good performance e.g. for nutrients removal. The advantage of kinetic coefficient determination is that the model can be adjusted to fit data and then used for analyzing alternatives to improve the process. This study investigates the efficiency of subsurface artificial wetland and determines its kinetic coefficients for nutrient removal.
Methods: The present study investigated the kinetics of biological reactions that occurred in subsurface wetland to remove wastewater nutrient. Samples were taken from 3 locations of wetlands for 6 months. The nutrient content was determined through measuring Total Kjehldahl Nitrogen (TKN), ammonium, nitrate, and phosphate values.
Results: Average levels for TKN, ammonium, nitrate, and phosphate in effluent of control wetland were 41.15, 23.59, 1.735, and 6.43 mg/L, and in wetland with reeds were 28.91, 19.99, 1.49 and 5.63 mg/L, respectively. First-order, second-order, and Stover-Kincannon models were applied and analyzed using statistical parameters obtained from the models (Umax, KB).
Conclusion: The nutrients removal at Yazd wastewater treatment plant was remarkable, and the presence of reeds in wetland beds was not very efficient in improving system performance. Other more efficient plants are suggested to be evaluated in the system. Stover-Kincannon kinetic model provided predictions having the closest relationship with actual data obtained from the field.
