Plate structure optimization and performance study of a new continuous flow electrocoagulation reactor

Abstract

Electrocoagulation (EC) process is an environmentally friendly and effective water treatment method. A folded plate EC reactor has been developed to remove pollutants such as azo dyes and COD from wastewater. There is a dead zone in the corner position of this electrocoagulation reactor, so this study aims to improve this problem and strengthen the EC mass transfer process in the reactor. A circular perforation treatment at the corner of the folded plate electrode is proposed to promote the exchange between the dead zone and the active zone and enhance the mixing strength. Taking methyl orange as the target pollutant, the effects of perforation diameter, perforation spacing and plate arrangement were considered, and these parameters were optimized by Box-Behnken model. The results show that the removal efficiency of 92.16% is obtained when the perforation diameter is 4 mm, the perforation spacing is 20 mm and the plate arrangement is 0.5 L height difference between the front and back plates. In addition, the RTD curve shows that the dead zone of the perforated electrode is lower, the dimensionless variance is larger, and the mixing effect is better. The cost was reduced by perforation design and optimization of operating parameters, and the COD removal efficiency of 16.8% and the decolorization efficiency of 17.4% were increased in pharmaceutical wastewater.