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Effect Of Different Shapes Of Air Diffusers On Removal Of Chemical Oxygen Demand Of Wastewater In Activated Sludge Process

N. Dashora, D. Bhatkhande, M. Deosarkar, S. Khamparia

Abstract


Abstract

One of the challenges faced in activated sludge process is the low solubility of oxygen in wastewater, affecting the microbial activity due to mass transfer limitations and ultimately hampering the effluent quality. To overcome this limitation various types of diffusers have been in use but the configuration in which the aerators must be placed is still an open question. A series of experiments were conducted using different shapes of diffuser namely I, E and Hand efficiency of these were compared for removal of COD at low and high ranges for same amount of hydraulic retention time. Best results were observed for E shaped diffuser at high COD loadings and COD removal efficiency of 79.94% was obtained whereas I and H shape gave removal efficiency of 50% and 70% respectively. At low COD values, H shaped diffuser performed better with COD removal efficiency of 68.497% while E and I shaped diffuser gave COD removal efficiency of 46.153% and 33.625% respectively. I shaped aerator did not produce effective results in both the cases.

Keywords:Activated sludge process, chemical oxygen demand, hydraulic retention time, diffuser configuration.


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References


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