Review of the factors relevant to the design and operation of an electrocoagulation system for wastewater treatment

Abstract

Electrocoagulation (EC) is a water treatment technology that has been proven effective at the bench scale for the removal of a wide variety of contaminants from water and wastewater. It is an electrochemical process that involves using a sacrificial anode to generate cations for coagulation. It also evolves hydrogen gas at the cathode, which some researchers have suggested can be used for natural flotation. EC has a number of advantages over conventional chemical coagulation (CC). For instance, solid metal electrodes tend to be easier to move and store than corrosive chemical salts. Furthermore, EC tends to increase solution pH, rather than consume alkalinity like chemical coagulants. However, unlike with CC, there are no standardized procedures for jar testing with EC, or for designing EC systems. Much of the current EC literature focuses on the treatment of a specific water or wastewater using custom EC systems. In an attempt to provide guidance for EC cell design, this paper reviews some of the current literature in four parts: electrodes, electrolyte, power source, and operational parameters.