Simultaneous Ammonia Nitrogen and Phosphorus Removal from Micro-Polluted Water by Biological Aerated Filters with Different Media

In this study, volcanic rock, ceramsite, and zeolite as media in biological aerated filters (BAFs) were evaluated on simultaneous ammonia nitrogen and phosphorus (SNP) removal performance in micro-polluted water. The highest NH4+-N removal efficiencies were 92.3% for zeolite BAF, and the highest PO43--P removal efficiencies were 67.4% for volcanic rock BAF. Zeolite BAF and volcanic rock BAF were more suitable for ammonia nitrogen and phosphorus removal than ceramsite BAF under various conditions. Ammonia nitrogen and phosphate removal in BAFs were promoted effectively with air/water = 1:1, hydraulic retention time = 3 h, low pollution loads, and a temperature of 10 degrees C. Also, the bacterial community results revealed that the long-time operation stage samples had the highest bacterial diversity in the volcanic rock BAF. The main bacterial species at a family level, including Nocardiaceae, Moraxellaceae, Burkholderiales, and Nitrospia, have a close association with SNP removal. These results demonstrated that volcanic rock BAF is more suitable to treat the micro-polluted water with the low content of ammonia nitrogen and phosphorus.