Perbandingan kinerja penyisihan amonia nitrogen dari air limbah domestik dengan menggunakan membrane aerated biofilm reactor (MABR) dan bio-kleen sewage system di PT. Gs battery, Sunter = Perfomance comparison of ammonia nitrogen removal from domestic wastewater by using membrane aerated biofilm reactor (MABR) and bio kleen domestic sewage system in PT. Gs battery, Sunter