Application of Hybrid Activated Sludge Reactor to Improve Activated Sludge Process for Oily Wastewater Treatment

Document Type : Research Paper

Authors

1 M.Sc. Student, Dept. of Chemical Eng., Sharif University of Tech., Tehran

2 Prof., Dept. of Chemical Eng., Sharif University of Tech., Tehran (Corresponding Author) (+98 21) 66165486 alemzadeh@sharif.edu

3 Prof., Dept. of Chemical Eng., Sharif University of Tech., Tehran

4 B.S. Student, Dept. of Chemical Eng., Sharif University of Tech., Tehran

Abstract

Activated sludge process is one of the well-establish methods for biological treatment of oily wastewater, which use in Iranian oil refineries. However, the process involved many problems such as low efficiency at high concentration of hydrocarbon, instability during hydraulics shocks and bulking phenomena. In this paper attached and suspended growth was used to improve conventional activated sludge treatment process. A hybrid activated sludge reactor, with 34.5 liter capacity, was used in order to treat synthetic high CODs oily wastewater and the results were compared with those obtained from conventional activated sludge reactor. Novel media used in this fixed-film biofilm bioreactor, provided a high surface area-to-volume ratio (600m2/m3). Reactor biodegradability for COD and TPH was evaluated for different hydraulic retention time (HRT) and oil pollution concentration. In optimum condition (T= 27 ºC, pH= 7.5, DO= 4.1mg/l, recycle sludge ratio= 1 and COD/TPH= 2.5) the removal efficiency of HASBR for TPH and COD were 90% and over 95% respectively which showed a significant difference in comparison with the conventional activated sludge reactor in the same conditions. Therefore, existing conventional activated sludge plants could be upgraded and improved by changing the reactor configuration and introducing support media into aeration tank.

Keywords

References

1- Jantrania, A., and Gross, M. (2006). Advanced onsite wastewater systems technologies, J. CRC Press, University of Arkansas, Fayetteville, Arkansas, USA.
2- Hamza, D., Mohammed, A., and Ibrahim, S. (2009). “Kinetics of biological reduction of chemical oxygen demand from petroleum refinery wastewater.” J. of Researcher, 57, 1-12.
3- Wenyu, X., Li, Zh., and Jianjun, CH. (2007). “Treatment of slightly polluted wastewater in an oil refinery using a biological aerated filter process.” J. of Natural Sciences, 12(6), 1094-1098.
4- Chavan, A., and Mukherji, S. (2008). “Treatment of hydrocarbon-rich wastewater using oil degrading bacteria and phototrophic microorganisms in rotating biological contactor: Effect of N:P ratio.” J. of Hazardous Materials, 154, 63-72.
5- Tizghadam, M., Dagot, Ch., and Baudu, M. (2008). “Wastewater treatment in a hybrid activated sludge baffled reactor.” J. of Hazardous Materials, 154, 550-557.
6- Saien, J., and Nejati, H. (2007). “Enhanced photo-catalytic degradation of pollutants in petroleum refinery wastewater under mild conditions.” J. of Hazardous Material, 148, 491-499.
7- Belanche, L., Valdes, J.J., Comas, J., Roda, I.R., and Poch, M. (2000). “Prediction of the bulking phenomenon in wastewater treatment plants.” J. of Artificial Intelligence in Engineering, 14, 307-317.
8- Xianling, L., and Jianping, W. (2005). “The pilot study for oil refinery wastewater treatment using a gas–liquid–solid three-phase flow airlift loop bioreactor.” J. of Biochemical Engineering, 27, 40-44.
9- Tyagi, R.D., and Tran, F.T. (1993). “A pilot study of biodegradation of petroleum refinery wastewater in a polyurethane-attached RBC.” J. of Process Biochemistry, 28, 75-82.
10- Wanner, J., Kucman, K., and Grau, P. (1988). “Activated sludge process combined with biofilm cultivation.” J. of Water Resource, 22, 207-215.
11- Moharram, F., and Renu, B. (2005). “A simplified model for the steady-state biofilm-activated sludge reactor.” J. Environmental Management, 74, 245-253.
12- Lenore, S., Clescerl, A.E., Greenberg, A., and Eaton, D. (1998). Standard method for the examination water and wastewater, 2nd Ed., APHA, AWWA and WPCF, Washington, DC.
13- Sikder, M., and Selimuzzaman, D. (2006). “Treatment of petroleum refinery wastewater using TiO2-Mediated photocatalysis.” M.Sc. Thesis of King Fahad University of Petroleum and Minerals, Saudi Arabia.
14- Hosseini, S.H., and Borghei, S.M. (2005). “The treatment of phenolic wastewater using a moving bed
bio-reactor.” J. of Process Biochemistry, 40, 1027-1031.
15- Rodegers, M. (1999). “Organic carbon removal using a new bioreactor.” J. of Water Resource, 33, 1495-1499.
16- Bihan, Y.L., and Lessard, P. (2000). “Monitoring biofilter clogging: Biochemical characteristics of the biomass.” J. of Water Resource, 34(17), 4284-4294.
17- Saeidi, M., and Khalvati Fahlyani, A. (2009). “COD reduction in effluent from southern Pars gas refinery using electrocoagulation.” J. of Water and Wastewater, 73, 40-48. (In Persian)
Journal of Water and Wastewater; Ab va Fazilab ( in persian )
Volume 24, Issue 1 - Serial Number 1
Serial number:85
March 2013
Pages 43-52

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