Electrode design for EC removal of emulsified oil in water and mechanism study via COMSOL simulation

The porous electrodes used in the EC treatment of emulsified oil wastewater were designed, and a study of the synergistic electro-flotation mechanism in this process was conducted using COMSOL Multiphysics simulation software. The experimental results showed that the best treatment effect was achieved when the aluminum plate was used as the anode and cathode. Under different plate combination, the combination of perforated anode and perforated cathode showed higher processing efficiency. When the number of perforations was 16, the removal efficiency was the highest, and the removal rate of COD was 97.58% and the removal rate of oil content was 96.09%. In the simulation part, the numerical simulation model of the oil droplets in the O/W emulsion under the action of electric field was constructed by COMSOL software, and the influence of the electric field on the demulsification process of the oil droplets was analyzed. The results showed that the electric field strength of the perforated edge of the perforated plate was significantly enhanced, and the enhanced electric field increased the discharge current, thereby strengthening the electrochemical reaction on the electrode surface, accelerating the formation of flocs, and improving the removal efficiency of pollutants. In addition, air flotation can significantly accelerate the aggregation and fusion of oil droplets, and accelerate the demulsification process of emulsified oil. When the perforated plate was used as the cathode, more hydrogen bubbles can be generated, which further enhanced the air flotation effect and significantly improved the treatment efficiency of emulsified oil wastewater.