滤层曝气对炭砂双层滤池去除氨氮的影响

通过现场中试试验，考察了不同气水比和曝气深度下滤层曝气对炭砂生物滤池氨氮去除效果的影响。试验结果表明滤池对氨氮去除量随着气水比和曝气深度的增加呈现出先增加后不变的趋势，炭砂双层滤池对NH3-N的去除限为2．8～3．0mg／L。在滤池某一深度进行曝气，当气水比小于0．1时，增加气水比，增大的是滤池0～0．5m滤段滤料对氨氮的去除；当气水比为0．1～0．25时，增加气水比，增加的是0．5～0．9m滤段滤料对氨氮的去除。充足的气水比条件下，在0．4m深度以上曝气，提高的是0～0．5m滤段的氨氮去除效果，在0．4～0．8m深度曝气，提高的是0．5～0．9m的氨氮去除效果，0．9m滤段以下滤料对氨氮基本没有去除作用。为保证出水浊度，建议在滤池0．6m深度对滤池进行曝气。

Influence of Ammonia Nitrogen Removal in GAC-Sand Dual Media Filter by Filter Layer Aeration

Throughout the pilot-scale experiments, the effects of different gas-water ratios and aeration depths on ammonia nitrogen removal were studied. The results show removal capacity of ammonia nitrogen increases firstly, then keeps constant with the increasing of gas-water ratios and aeration depths, and the maximum ammonia nitrogen removal capacity of GAC-sand dual media filter is 2.8 - 3.0 mg/L. In a certain depth＇s aeration, when the gas-water ratio is less than 0. 1, the ammonia nitrogen removal of 0 - 0.5 increases with the increasing of the gas-water ratios. When the gas-water ratio is 0. 1 - 0.25, to increase the gas-water ratio, the ammonia nitrogen removal of capacity 0.5 - 0.9 m increases. Under the conditions of adequate dissolved oxygen, when the aeration depth is less than 0.4 m, the ammonia nitrogen removal capacity of 0 - 0.5 m increases, when the aeration depth is between 0.4 - 0.8 m, the ammonia nitrogen removal capacity of 0.5 - 0.9 m increases there is almost no ammonia nitrogen removal of below 0.9 m. To ensure the turbidity of the water, it is suggested that aeration should be in 0.6 m depth of filter.