Influência de diferentes padrões de escoamento sobre os fenômenos de eletrodeposição do zinco.

Abstract

Zinc is a metal that has a wide applicability due mainly to its preferential corrosion property, making it one of the most produced metals in the world, and the process of obtaining zinc is usually carried out through a hydrometallurgical route, where the last stage consists of the zinc electrowinning process through the passage of an electric current on electrodes submerged in an electrolytic solution contained in a series of reactors. The flow behavior and the way that zinc-rich electrolyte solution is fed has a direct influence on its renewal rate in the region between the electrodes, where directly impacting variables such as current efficiency, metal zinc deposition rate and specific energy consumption. Thus, to evaluate the impact that different flow behavior has on those variables, a fluid dynamic modeling using the finite volume method was developed using the Ansys CFX 15 software. The Eulerian-Eulerian approach was adopted, with the mathematical model formed for equations of mass conservation, linear momentum, turbulence, thermodynamics and electrochemical kinetics. As a result, it was observed that improving the way the solution rich in zinc is fed into the cell, the mass transport by convection to region between electrodes increase, so the rate of zinc deposition and current efficiency increases too.