接触氧化过滤去除地表水中的氨氮

接触氧化过滤工艺普遍用于去除地下水中的氨氮，在去除地表水中氨氮的应用较少。为了对此工艺去除地表水中的氨氮进行研究，以附有铁锰氧化物的石英砂为滤料填充滤柱，测试了滤柱对地表水中的铁、锰和氨氮的去除效果，并重点分析了影响氨氮去除的主要因素。结果表明：当滤速为8 m·h-1，进水铁、锰、氨氮浓度分别为0.6、1.1和1.8 mg·L-1时，滤柱对3种污染物的去除率分别为83.3%，95.3%和80.6%，3种污染物的出水浓度均达标。此外，升高进水温度、提高进水碱度可增大氨氮的去除率。当温度由8℃增大到14℃时，氨氮去除率提高了近一倍。进水投加NaOH（浓度为4 mg·L-1）时，氨氮的平均去除率比不投加NaOH时高23.1%。

Removing NH4+-N from surface water by contact oxidation filtration

The contact oxidation filtration process is widely used to remove ammonia from groundwater but rarely from surface water. Quartz sand coated with iron and manganese oxides was used as a filter material to test the removal efficiencies of iron, manganese, and ammonia from surface water, and the main influencing factors were analyzed. The experimental results achieved removal efficiencies of 83.3%, 95.3%, and 80.6% for iron, manganese, and ammonia (filtration rate 8 m·h-1; initial concentrations in water:0.6, 1.1, and 1.8 mg·L-1), respectively. Consequently, the concentrations of all three pollutants met their respective effluent standards. Additionally, increasing the temperature and alkalinity of the input water can improve ammonia removal efficiency. When the temperature increased from 8 to 14℃, ammonia removal efficiency was doubled. When NaOH (4 mg·L-1) was added to the input water, average ammonia removal efficiency increased by 23.1% compared to that without the addition of NaOH.