Mathematical modelling of active chlorine based UV/Electro-Fenton-like process: Elucidation of reactor engineering implications to guide scaling-up

Abstract

Electrochemically-driven processes are emerging as competitive solution for environmental remediation. When considering scaling of processes accurate engineering modeling can aid on process engineering design for real application. This work defines step stones on electrochemical reactor engineering understanding and sets guidelines for UV/Electro-Fenton-like process modelling to ease scale-up to pilot plant. The UV/Electro-Fenton-like process considers the use of a flow-by cell with parallel plate electrodes to electrogenerated in situ active chlorine species. The turbulent convection-diffusion equation was solved for mass transport simulations considering for the first time a simplified kinetic model in recirculation mode of operation to remove a model contaminant. Tertiary current distribution was solved to simulate the electrochemical production of HClO. The theoretical analysis evidences a quasi-uniform current distribution in the working electrode, a continuous consumption of chloride, and sustained production of HClO for effective treatment at larger scale system level. Comparisons between numerical and experimental results evidence high predictability of the designed model that can be effectively translated for other electrochemically-driven processes.