Research on the nitrogen removal efficiency and mechanism of deep subsurface wastewater infiltration systems by fine bubble aeration

To respond to the reality that it is difficult and expensive to deal with wastewater rich in ammonia nitrogen (NH4+-N) in the countryside, fine bubble aeration technology and a deep subsurface wastewater infiltration system are coupled to investigate their nitrogen removal efficiency and mechanism. The results show that fine bubble aeration can improve the effectiveness of a deep subsurface wastewater infiltration system in treating wastewater that is rich in ammonia nitrogen, and effective nitrogen degradation can be attained by limited aeration. The effluent Chemical Oxygen Demand (COD), NH4+-N and total phosphorus (TP) can reach the first grade A standard required by “Discharge standard of pollutants for municipal wastewater treatment plants” (GB18918-2002). The effect of the fine bubble aeration technology is beneficial when it is used to strengthen land-treatment technology.