Effect of Different Configurations of Mechanical Aerators on Oxygen Transfer and Aeration Efficiency with respect to Power Consumption

This paper examines the use of mechanical aerator for oxidation-ditch process. The rotor, which controls the aeration, is the main component of the aeration process. Therefore, the objective of this study is to find out the variations in overall oxygen transfer coefficient (KLa) and aeration efficiency (AE) for different configurations of aerator by varying the parameters viz. speed of aerator, depth of immersion, blade tip angles so as to yield higher values of KLa and AE. Six different configurations of aerator were developed and fabricated in the laboratory and were tested for abovementioned parameters. The curved blade rotor (CBR) emerged as a potential aerator with blade tip angle of 47°. The mathematical models are developed for predicting the behaviour of CBR w.r.t kLa and power. In laboratory studies, the optimum value of KLa and AE were observed to be 10.33 h-1 and 2.269 kg O2/ kWh.

Authors:

• S.B. Thakre
• L.B. Bhuyar
• S.J. Deshmukh

Keywords:

• Aerator
• Aeration efficiency
• Dissolve Oxygen
• Overall oxygen transfer coefficient
• Oxidation ditch.

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