Abstract
The aim of this paper was to study the performance of a single-stage rotating biological contactor with supplemental aeration in
terms of removal efficiency of organic and nitrogen content. Research was based on fifteen samples collected during the four
year period. The wastewater was low strength with maximal measured concentration of 362 mg COD/l, 100 mg NH4/l, and 324
mg TSS/L. The maximal measured removal efficiency of COD (chemical oxygen demand) and TSS (total suspend solids) were
71% and 56%, respectively. The high rate of nitrogen removal was achieved using supplemental aeration. The removal efficiency
of NH4, NO2 and NO3 were 83%, 60% and 52%, respectively.