The Effect of Using Baffles on the Rate of Mass Transfer of a Cylindrical Stirred Tank Reactor

Abstract:

Owing to the high mixing capacity, the stirred tank reactor is the key class of reactors in the chemical process industry and pharmaceutical industry. The mass transport nature of a batch stirred tank reactor with a fixed copper wall with a cylinder form was studied using copper dissolution in acidified dichromate which is controlled by diffusion. Variables analyzed included the speed of rotation of the impeller, the shape of the impeller and the physical specifications of the solution and the existence of baffles. The data were correlated for the conditions 3667.323 < Re < 34993.18 and 960 < Sc < 1364, for radial flow by the equation: Sh =0.3453 *Sc^1/3*Re^0.66 but for axial flow by the equation: Sh =0.5866 *Sc^1/3*Re^0.59. Through speed of rotation of the impeller increases,it allows the rate of mass transfer from the fixed bed to the solution to rise. The radial-flow turbine is more effective than the axial-flow turbine in increasing the rate of mass transfer. The usage of baffles plays a significant role in rising the rate of mass transfer. Using baffles; the correlation will be Sh =0.0769 *Sc^1/3*Re^0.84 for radial flow and Sh =0.1157 *Sc^1/3*Re^0.78 for axial flow. The purpose of this research is to estimate the rate of mass transport that can be required in corrosive reactions, and also to maximize the mass transfer rate that can be achieved in other processes, such as electroplating in presence of baffles.

• Periodical: Materials Science Forum (Volume 1008)
• Pages: 168-176
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1008.168
• Online since: August 2020
• Authors: Fathy Shokry*, Dina Ahmed El-Gayar, Marwa Abd El-Fattah, H.A. Farag, Gomaa H. Sedahmed
• Keywords: Baffled Reactor, Cylindrical Reactor, Impeller Geometry, Mass Transfer Coefficient, Rotation Speed

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