Research on A Novel Combined Technology Treated High-salt Organic Wastewater

Abstract

In this study, a novel combined technology treated high-salt organic wastewater was proposed by ozone oxidation-coupled electrodialysis technology. Both the decomposition law of organic matter and the migration rule of salt ions during the coupled process were analyzed. The results showed that without adjusting the pH, when the ozone concentration was 20 g/L and the ozone reaction time was 10 min, the removal rates of COD, UV254, and ammonia nitrogen were 53.89%, 42.20%, and 40.29%, respectively. The concentration changes of the major anions and cations were extremely small, and the separation rates of Cl^- and SO₄^2- were only 4.54% and 5.56%, respectively. The chromaticity varied from 2000 to 800. Ozone pretreatment improved the operating environment during electrodialysis. After electrodialysis treatment, the separation efficiencies of Cl^-, SO₄^2-, Na⁺, and K⁺ were significantly improved. Under conditions of 15 V and 1 A and a reaction time of 60 min, the separation efficiencies of Cl^-, SO₄^2-, Na⁺, and K⁺ were 94.24%, 86.37%, 96.12%, and 91.08%, respectively. The total desalination efficiency of the entire process is 92.24%. The combined process provides a new solution for the treatment of high salt and high organic wastewater.