Enhancing nitrogen removal from domestic sewage with low C/N ratio using a biological aerated filter system with internal reflux-coupled intermittent aeration

Biological aerated filter (BAF) systems with internal reflux-coupled intermittent aeration enhance the removal of nitrogen pollutants from low-C/N ratio domestic sewage. Two experimental systems with the same specifications, a BAF system with internal reflux-coupled intermittent aeration (system A) and a traditional BAF system (system B) was constructed to explore the efficiency of nitrogen removal. Overall, the nitrification in system B was higher than that in system A due to the influence of aeration model. Conversely, the system A can use the alternating anoxic (DO