Performance of continuous electroflotation of O/W emulsion using packed bed type sacrificial electrode as an anode

The performance of continuous electroflotation of an O/W emulsion was examined in apparatus equipped with a flotation cell which was comprised of sacrificial electrodes using aluminum (Al) pellets as an anode. As a result, a first-order kinetic rate model was applied to represent the flotation process. The flow pattern in the cell was approximated by two tanks-in-series model. The equation of the percentage oil removal was a function of the rate constant and the residence time in the cell, and it correlated the data very well. The rate constant was proportional to the dissolution rate of Al per unit time, regardless of pellet type and operating conditions. A linear relationship was obtained between the dissolution rate per unit time and unit surface area of pellets and the electrical current density per unit cross sectional area of packed bed orthogonal to the direction of the electric current. The method was effective for the treatment of emulsion containing various surfactants. © 1996, Society of Chemical Engineers, Japan. All rights reserved.