Reza Shokoohi
1, Hossein Movahedian
2, Abdollah Dargah
1*1 Department of Environmental Health Engineering, School of Public Health, Hamadan University of Medical Sciences, Hamadan, IR Iran
2 Department of Environmental Health Engineering, School of Public Health, Isfahan University of Medical Sciences, Isfahan, IR Iran
*Corresponding Author: * Corresponding author: Abdollah Dargahi, Department of Environmental Health Engineering, School of Public Health, Hamadan University of Medical Sciences, Hamadan, IR Iran. Tel: +98-9141597607, E-mail: a.dargahi29@yahoo.com, Email:
a.dargahi29@yahoo.com
Abstract
Phenol is a toxic hydrocarbon that has been found in the wastewater of several industries, including the petroleum and petrochemical
industries. The discharge of untreated wastewater from these industries causes environmental pollution, especially in water.
The aim of this study was to evaluate the efficiency of phenol removal from wastewater using a biofiltration system. In this experimental
study, a cylindrical plexiglass biofilter reactor with an effective volume of 12 liters was used. A total of 30 pcs of plastic grid
discs were placed inside the reactor by plastic pipes to maintain the biofilm media in the reactor. The microorganisms used in this
study were obtained from the biological sludge of a municipal wastewater treatment plant. The reproduction and adaptation of
the microorganisms to 500 mg/L of phenol lasted three months. The effects of pH, phenol, nitrogen, phosphorus, glucose concentration,
and hydraulic retention time on the biofilter system’s performance was evaluated. The results of this study showed that in
optimal conditions, this system can reduce the phenol concentration from 500 mg/L to zero within about 4 hr. Maximum efficiency
occurred in pH = 7, and the proper COD/N/P ratio was 100/10/2, respectively. In general, this biofilter system is capable of removing
500 mg/L of phenol concentrations and an organic load of 4 - 4.5 kg COD/m3
.d within 4 - 5 hr. with high efficiency