Treatment of Ammonia Nitrogen Wastewater in Low Concentration by Two-Stage Ozonization

作者：Xianping Luo, Qun Yan, Chunying Wang, Caigui Luo, Zhou Nana, Chensheng Jian · 发表于：International Journal of Environmental Research and Public Health · 年份：2015 · DOI：10.3390/ijerph120911975 · 被引用次数：104 · 研究领域：Advanced oxidation water treatment、Water Quality Monitoring and Analysis、Industrial Gas Emission Control

Ammonia nitrogen wastewater (about 100 mg/L) was treated by two-stage ozone oxidation method. The effects of ozone flow rate and initial pH on ammonia removal were studied, and the mechanism of ammonia nitrogen removal by ozone oxidation was discussed. After the primary stage of ozone oxidation, the ammonia removal efficiency reached 59.32% and pH decreased to 6.63 under conditions of 1 L/min ozone flow rate and initial pH 11. Then, the removal efficiency could be over 85% (the left ammonia concentration was lower than 15 mg/L) after the second stage, which means the wastewater could have met the national discharge standards of China. Besides, the mechanism of ammonia removal by ozone oxidation was proposed by detecting the products of the oxidation: ozone oxidation directly and ·OH oxidation; ammonia was mainly transformed into NO₃(-)-N, less into NO₂(-)-N, not into N₂.