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A. Bushra ¹, Y. Chandra ¹, S. D. Bhattacharya ¹

Affiliations
1 University of Roorkee, Roorkee, IN

Abstract

The present study deals with the determination of minimum impeller speed for complete liquid-liquid-gas (three-phase) dispersion, N_cdg, in a mechanically agitated baffled vessel of 0.2038 m i.d. using a turbine impeller. Mineral oil (diesel and kerosene) and water were used as the dispersed and continuous phases respectively. Compressed air was used as the gas phase through a ring sparger. N_cdg was determined visually and also by the sampling method. The results of this work show an excellent agreement between the values of N_cdg SO obtained and those obtained using the visual method. A correlation has been proposed for three-phase (liquid-liquid-gas) system for dif'ferent volume fractions of the dispersed phase.

Keywords

Turbine Impeller, Dispersed Fraction, Off-Bottom Clearance, Gas Sparging, Liquid-Liquid Dispersion.

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A. Kumar ¹, S. D. Bhattacharya ¹

Affiliations
1 Department of Chemical Engineering, University of Roorkee, Roorkee-247 667, IN

Abstract

The transport of coal-slurry through pipelines with water as carrier is a viable proposition. During transportation, water gets contaminated as a result of leaching of inorganic and organic carbon from coal. The biochemical and'chemical oxygen demand (BOD and COD respectively) of the wastewater generated in the laboratory were 59.49 mg/l and 343.0 mg/l respectively. Both activated and commercial charcoals were found to be effective in reducing the BOD and COD to acceptable levels. Adsorption kinetics studies were performed and Lagergren model was found to fit the data. Effects of temperature, pH and contact time on adsorption behaviour were also studied.

Keywords

BOD, COD, Commercial Charcoal, Wastewater Treatment, Adrorptibn.

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