(177c) Kinetics and Performance of Phosphate-Removal From Hot Industrial Effluents Using a Continuous Flow Electrocoagulation Reactor

This work investigates the reaction kinetics of phosphate removal from hot industrial effluent streams in a continuous-recirculation electrocoagulation reactor using monopolar aluminum electrodes. The effects of several variables on the unit performance were also investigated. Results show that the rate of phosphate removal follows a first order reaction kinetics and that the percent of phosphate removal increases by increasing the solution circulation flow rate and the solution temperature. Moreover, an economical analysis of the process based on phosphate percent removal per unit energy consumed reveal that the process economy drastically decreases by increasing the employed electrodes current density. Data show that an increase in current density from 5 to 50 mA/cm² leads to around 87% decrease in percent of phosphate removed/unit energy consumed.

Based on data generated in this study, the paper presents a thorough analysis and discussion of the electrocoagulation reaction kinetics, the reaction activation energy, and the reaction rate controlling mechanism as well as the effects of several important parameters on the reactor’s performance and the phosphate-removal process economic viability.