Performance of two new electrochemical treatment systems for wastewaters

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.