Investigation of the Excess Sludge Reduction in SBR by Oxidizing Some Sludge by Ozone

Document Type : Research Article

Authors

1 Department of Environmental Health, Ahvaz Jondishapoor University, Ahvaz, I.R. IRAN

2 Department of Environmental Engineering, University of Tehran, Tehran, I.R. IRAN

3 Department of Environmental Engineering, Islami Azad University, Ahar Branch , I.R. IRAN

Abstract

The excessive biological sludge production is one of the disadvantages of aerobic process such as SBR. So the problem of excess sludge production along with its treatment , and disposal in aerobic processes in municipal and industrial waste water can be seen in many parts of the world even in our country . to solve the problem of excess sludge production , reducing in by oxidizing some of the sludge by Ozone is a suitable idea , thus reducing the biomass coefficient as well as the sewage sludge disposal.   In this study, Two SBR reactors with of 20 liter being controlled by on-line system are used. After providing the steady state in the reactors, along the 8 month research sampling and testing parameters such as COD, MLSS, MLVSS, DO, SOUR, SVI, residual ozone and Yield coefficient were done. The results showed that during the solid retention time of 10 days the kinetic coefficient of Y and Kd was 0.58 (mg Biomass / mg COD) and  0.058 (1/day) respectively. At the next stage of research, different concentrations of ozone in one liter of  the returned sludge to   reactor were used to reduced the excess biological sludge production. The results showed that the 20 mg ozone per gram of MLSS in one liter of the returned sludge to   reactor is able to reduce Yield coefficient from 0.58 to 0. 28 (mg Biomass/mg COD),In other words, the biological excess sludge by 52 % .but the soluble COD increased slightly in the effluent and the removal percentage decreased  from 92 in blank reactor to 64 in test reactor. While the amount of SVI and SOUR in this consumed ozone concentration reduced 9 mgO2/h.gVSS and 20 ml/g respectively. No sludge was seen in the 25 mg ozone concentration per gram of MLSS in one liter of  the  returned sludge to reactor.

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References

[1] Metcalf and Eddy, “Wastewater Eng. Treatment”, Disposal and Reuse, NewYork, USA. McGraw Hill, Chapter 11(2003).
[2] Bitton, G., “Wastewater Microbiology”, New York, Willey-Liss, Chapter 9 ( 2002).
[3] Canales, A., Pareilleux, A., Rols, J.,. Decreased Sludge Production Strategy for Domestic Waste Water Treatment, Water Sci., 30, 106(1994).
[4] Liu, Y., Tay, J., A Kinetic Model for Energy Spilling Associated Product Formation in Substrate-Sufficient Continuous Culture, J. Appl. Microbiol., 88, 663 (2000).
[5] Liu, Y., (2000). Effect of Chemical Uncouple on the Observed Growth Yield in Batch Culture of Activated Sludge, Water Res., 3, 2025 (2000).
[6] Liu, Y., Tay, J., Strategy for Minimization of Excess Sludge Production from the Activated Sludge Process, Biotech Adv., 2, 97 (2001).
[7] Liu, Y., Chemically Reduced Excess Sludge Production in the Activated Sludge Process, Chemosphere, 50, 7(2003).
[8] Rocher, M., Goma, G., Begue, AP., Louvel, L., Rols, JL., Towards a Reduction in Excess Sludge Production in Activated Sludge Processes, Biomass Physicochemical Treatment and Biodegradation, Appl. Microbial Biotech., 51, 883 (1999).
[9] Rocher, M., Roux, G., Goma, G., Begue, AP., Louvel, L., Rols, JL., Excess Sludge Reduction in Activated Sludge Processes by Integrating Biomass Alkaline Heat Treatment, Water Sci. Tech., 44, 437 (2001).
[10] Abbassi, B., Dullstein, S., Rabiger, N., Minimization of Excess Sludge Production by Increase of Oxygen Concentration in Activated Sludge, Wat. Res., 34, 20 (2000).
[11] Low, E., Chase, H., Reducing Production of Excess Biomass During Waste Water Treatment, Wat. Res., 5, 1119 (1999).
[12] Low, E., Chase, H., The Use of Chemical Uncouples for Reducing Biomass Production During Biodegradation, Water Sci. Tech., 7, 399 (1998).
[13] Low, W., Chase, H., Milner, M., Curtis, T., Uncoupling of Metabolism to Reduce Biomass Production in the Activated Sludge Process, Water Res., 34, 3204 (2000).
[14] Gallard, H., Von Gunten, U., Chlorination of Natural Organic Matter: Kinetics of Chlorination and of THM Formation, Water Res., 36, 65 (2002).
[15] Saby, S., Djafer, M., Chen, GH., Feasibility of Using a Chlorination Step to Reduce Excess Sludge in Activated Sludge Process, Water Res., 36, 656 (2002).
[16] Sabya, S., Djafera, M., HaoChenb, G., Effect of Low ORP in Anoxic Sludge Zone on Excess Sludge Production In OSA Activated Sludge Process, Water Res., 37, 11 (2003).
[17] Wunderlich, R., Barry, J., Greenwood, D., Startup of a High-Purity Oxygen Activated Sludge System at the Los Angeles Country Sanitation Districts,J. Wat. Poll. Control Fed., 57, 1012 (1985).
[18] Chen, G., Saby, S., New Approaches to Minimize Excess Sludge in Activated Sludge System,
Water Sci. Techno., 44 , 203 (2003).
[19] Park, Y.G.,. Impact of Ozonation on Biodegradation of Trihalomethanes in Biological Filtration System, J. Ind. Eng. Chem., 7, 349 (2001).
[20] Sakai, Y., Fukase, T., Yasui, H., Shibata, M., An Activated Sludge Process Without Excess Sludge Production, Water Sci. Tech., 36, 163 (1997).
[21] Wojtenko, I., Stinson, M.K., Field, R., Performance of Ozone as a Disinfectant for Combined Sewer Overflow, Critical Rev. Environ. Sci. Tech., 31, 295 (2001).
[22] Yasui, H., Nakamura, K., Sakuma, S., Iwasaki, M., Sakai, Y., A Full-Sale Operation of a Novel Activated Sludge Process Without Excess Sludge Production, Water Sci. Tech., 34, 395 (1996).
[23] Yasui, H., Shibata, M., An Innovative Approach to Reduce Excess Sludge Production in the Activated Sludge Process, 30, 11 (1994).
[24] Huang, X., Liang, P., Qian, Y., Excess Sludge Reduction Induced by Tubifex in a Recycle Sludge Reactor, J. of Biotechnology, 127, 443 (2007).
[25] Kamiya, T., Hirotsuji, J., New Combined System of Biological Process and Intermittent Ozonation for Advanced Wastewater Treatment, Water Sci., 38, 145 (1998).
[26] Liang, P., Huang, X., Qain, Y., Excess Sludge Reduction in Activated Sludge Process Through Predation of Aeolosoma Hemperichi, Chem. Eng. J., 28, 117 (2006). 
[27] Liang, C., Huang, X., Qian, Y., Wei, Y., Ding, G., Determination and Comparison of Sludge Reduction Rates Caused by Microfaunas, Predation, Bioresource Tech., 97, 854 (2006).
[28] APHA; AWWA; WPCF, “Standard Method for the Examination of Water and Wastewater”, 22th Edition, APHA; NW Washington D.C (1995).
Iranian Journal of Chemistry and Chemical Engineering
Volume 28, Issue 4 - Serial Number 52
December 2009
Pages 95-104

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