Seyed Mostafa Khaezri - Department of Environmental Engineering, School of Environment and Energy, Science and Research Branch, Islamic AzadUniversity, Tehran, Iran
Hossein Jafari Mansoorian - Young Researchers and Elite Club, Hamedan Branch, Islamic Azad University, Hamedan, Iran- Environmental Health Engineering Research Center, Department of Environmental Health, Kerman University of Medical Sciences, Kerman, Iran
Gharib Majidi - Research Center for Environmental Pollutants, Qom University of Medical Sciences, Qom, Iran
Farideh Atabi - Department of Environmental Engineering, School of Environment and Energy, Science and Research Branch, Islamic AzadUniversity, Tehran, Iran

Background & Aims of the Study: The Horizontal roughing filters (HRF) are generallyformed with three layers. The size of the course at the beginning of the flow path is large and atthe end is small. This kind of layering increases absorption capacity while the solids entering thebed–depth gradually separate because of the decline in the holes’ diameters. This study aimed toexamine the efficiency of HRFs in removing total suspended solids (TSS) from effluent of awaste stabilization pond.Materials & Methods: This experimental study was conducted in 2013. The pilot project wastransferred to the Karaj wastewater treatment plant (waste stabilization pond), Alborz province ofIran. Then, the installation, equipping and start-up of the system began, using an effluenttreatment plant. Sampling was done from March to August in 3 rates of 0.5, 1 and 1.5 m/h,which was included simultaneous sampling from inlet and outlet HRF to determine theconcentrations of TSS.Results: The results showed that at filtration rates of 0.5, 1, and 1.5 m/h, the average of TSSremoval was equaled to 42.46, 56.65 and 33.22%, respectively. The removal efficiency of TSS atthe rate of 1m/h was more than 0.5 and 1.5 m/h rate (p<0.05). The Outlet value of TSS waslower than the standards which are set by the Environmental Standards Organization (ESO) (P <0.05).Conclusion: According to the results of this study, the HRF function was approximatelyadequate in TSS removal and can be a suitable option for improving the quality of stabilizationponds effluent.

Waste Stabilization PondHorizontal Roughing FilterTotal Suspended SolidIran