Treatment on low carbon-to-nitrogen micro-polluted water by layered biological aerated filter with floating and sunken media

Abstract

In order to improve the TN removal efficiency on low carbon-to-nitrogen micro-polluted water, in this study, a layered biological aerated filter (L-BAF) was built. The results showed that the removal efficiency for CODMn, NH3-N, and TN was 71.6–90.3%, 99.8–99.9%, and 57.8–65.7%, respectively, when the C/N ratio was kept at 3 and the volumetric flow rate was 0.072 m3 d−1. The L-BAF could improve the TN removal efficiency by about 20% compared to a traditional process. The L-BAF and traditional process removal efficiency for NH3-N and CODMn were similar. The kinetic performance of the L-BAF indicated that the relationship of CODMn removal efficiency with the influent CODMn concentration could be described by ln(C/C0) = −(0.0023/Q0C00.9398)H.