Performance of Two New Electrochemical Treatment Systems for Wastewaters

Abstract

Two types of practical electrochemical treatment systems (treatment capacities of 4 and 0.5 m³/h) were constructed. These systems generate radical species for effective oxidation of organic pollutants in wastewater, providing a novel treatment system for treating various kinds of wastewater. A series of experiments was performed using effluents from an anaerobic digester (EAD) of cattle wastewater, supernatants from primary sedimentation in a sewage plant (SPS), and domestic wastewater to evaluate the systems’ treatment abilities. As a result, for both EAD and SPS, the 4 m³/h system was found to remove 87–91% of T-P, 74–96% of T-N, 70–94% of NH₄-N, 88–91% of TOC, 75–87% of COD. Similarly, for wastewater, the 0.5 m³/h system was able to remove 62–90% of T-P, 83–92% of T-N, 90–100% of NH₄-N, 75–83% of TOC, 80–100% of COD. It was further demonstrated that the high-voltage pulses and ultrasonic treatment effectively decomposed NH₄-N and TOC due to the formation of radical species such as hydroxyl radicals and hypochlorite, T-P was removed by the electrocoagulation.

Keywords:

• Electrochemical treatment
• High-voltage pulse
• Ultrasonic treatment
• Wastewater
• Radicals
• Electrocoagulation