SCALE UP OF AN ELECTROCHEMICAL CELL OF TWO FACING DISKS WITH RADIAL DIVERGENT LAMINAR FLOW

  • F. Cœuret Lab. Thermocinétique, UMR CNRS 6607, E.P.U.N
  • T.Z. Fahidy Dept. of Chemical Engineering, University of Waterloo
Keywords: electrochemical cell, opposite disks, mass transport, scale-up

Abstract

The paper deals with theoretical aspects of scaling-up, and concerns an electrochemical cell working under isothermal mass transport control. The cell contains two closely-facing parallel circular disk electrodes [radius R2, separation distance 2a]. The electrolyte enters the cell through a central circular hole [radius R1] in one disk and flows radially between the disks in the laminar flow regime. Specifically, the work deals with the effect of the scale on stationary liquid-to-disk mass transport. Three cells were used, allowing a maximum scale factor of 12.5. Dimensional analysis of the mass transport problem yields the five dimensionless numbers R2/R1, 2a/(R2-R1), Re, Sh and Sc, to be correlated as:

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where the coefficient and the numerical exponents α, β, γ, follow from experiments. It is shown how scale-up is approached when the objective is to conserve the mass transport characteristics of a cell. The values of the dimensionless numbers calculated from the experimental data allow the establishment of an empirical correlation valid in a given range of the scale factor, and comparison with an approximate theoretical analytical solution. It is shown how scaling-up considerations are handled, what difficulties are and how, in the absence of a rigorous theoretical solution, experimental results can be employed for cell design up to industrial scale.

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Published
2020-07-14
How to Cite
Cœuret, F., & Fahidy, T. (2020). SCALE UP OF AN ELECTROCHEMICAL CELL OF TWO FACING DISKS WITH RADIAL DIVERGENT LAMINAR FLOW. Revista Mexicana De Ingeniería Química, 6(2), 211-217. Retrieved from http://www.rmiq.org/ojs311/index.php/rmiq/article/view/1900
Section
Process engineering