(2a) Increasing Power Savings in Removal of Oil from Industrial Effluents Via Electrocoagulation

Electrode passivation raises the power consumption. It is a concern for the longevity of the process, and increases the operating cost. It is thus the greatest operational issue with the electrocoagulation process. The objectives of the current investigation were to define the reactor configuration and optimum working conditions to maximize the amount of oil removal from an industrial effluent with minimum specific energy consumption. We show that power consumption per unit effluent treated can be greatly reduced by using a half-wave rectified alternating-current supply instead of a full alternating-current supply. We also developed a theoretical model for predicting oil separated over time in an electrocoagulator. To this end, we modified the model of Matteson et al [1] by dividing the electrocoagulator space into two regions, viz. the bulk region, where hydrodynamic and/or Brownian forces are dominant, and the electrode region, where the electrophoretic force is dominant. The model was in a good agreement with the experimental data.

[1] Matteson, M.J., Dobson, R.L., Glenn, R.W., Jr., Kukunoor, N.S., Waits, W.H. III, Clayfield, E.J., ?Electrocoagulation and separation of aqueous suspensions of ultrafine particles?, Colloids and Surfaces A: Physicochemical and Engineering Aspects 104 (1995) 101-109.