The performance of ammonia nitrogen removal by using membrane-aerated biofdm reactor as domestic wastewater treatment

High concentration of NH₃-N in wastewater discharges from sewage treatment plant can cause eutrophication of the surface water that has the negative impacts for aquatic ecosystems. Membrane-Aerated Biofilm Reactor (MABR) has been proposed as a wastewater technology to reduce NH₃-N concentration in domestic wastewater. This study observed the performance of NH₃-N removal in domestic wastewater using MABR. Domestic wastewater contains concentration of NH₃-N from 73-104.8 mg/L (0.12-0.24 kg NH₃-N/m³.d) and COD from 332-468 mg/L (0.56-1.05 kg COD/m³d). MABR was supplied by oxygen at the pressure of 20 kPa and study performed for 3 Hydraulic loading rate (HRT) variations which were 8, 10 and 12 h. After 33 days of running, the result showed COD/N ratio were about 3.9-5.72 with maximum efficiency of COD and NH₃-N removal occurred when HRT 12 h, reached 88 and 89.58%, respectively. This indicated that NH₃-N could remove by MABRat low COD/N ratio. Furthermore, autotrophs bacteria that responsible for oxidized NH₃-N to NO₂^- and NO₃^- have slower growth rates compared with heterotrophs bacteria. Thus, longer HRT provided benefit for nitrification process and high NH₃-N removal efficiency has been achieved.