Author/Authors :
Karimi، Ali نويسنده Department of Occupational Health, School of Public Health and Nutrition, Shiraz University of Medical Sciences, Shiraz, Iran Department of Occupational Health, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran , , Golbabaei، Farideh نويسنده , , Neghab، Masoud نويسنده Department of Occupational Health, School of Health and Nutrition, Shiraz University of Medical Sciences, Shiraz, Iran , , Pourmand، Mohammad Reza نويسنده Department of Medical Biotechnology, School of Advanced Technology, Tehran University of Medical sciences, Tehran, IR Iran , , Nikpey، Ahmad نويسنده School of Health, Qazvin University of Medical Sciences, Qazvin , , Mohammad، Kazem نويسنده , , Mehrnia، Momammad Reza نويسنده Biotechnology Group, School of Chemical Engineering, University College of Engineering, University of Tehran, Tehran, Iran ,
Abstract :
The present study examined the biodegradation rate of benzene vapors in a two phase stirred tank bioreactor by a
bacterial consortium obtained from wastewater of an oil industry refinery house. Initially, the ability of the microbial
consortium for degrading benzene was evaluated before running the bioreactor. The gaseous samples from inlet
and outlet of bioreactor were directly injected into a gas chromatograph to determine benzene concentrations.
Carbone oxide concentration at the inlet and outlet of bioreactor were also measured with a CO2 meter to
determine the mineralization rate of benzene. Influence of the second non-aqueous phase (silicon oil) has been
emphasized, so at the first stage the removal efficiency (RE) and elimination capacity (EC) of benzene vapors were
evaluated without any organic phase and in the second stage, 10% of silicon oil was added to bioreactor media as
an organic phase. Addition of silicon oil increased the biodegradation performance up to an inlet loading of
5580 mg/m3, a condition at which, the elimination capacity and removal efficiency were 181 g/m3/h and 95%
respectively. The elimination rate of benzene increased by 38% in the presence of 10% of silicone oil. The finding of
this study demonstrated that two phase partition bioreactors (TPPBs) are potentially effective tools for the
treatment of gas streams contaminated with high concentrations of poorly water soluble organic contaminant,
such as benzene.
