RESUMO
One of the main problems in application of MBR technology is lack of reliable kinetic parameters for process design. The activated sludge in the aerobic tank of an MBR municipal wastewater treatment plant was investigated therefore. Using oxygen utilization rate method, following kinetic parameters were measured: heterotrophic yield coefficient YH = 0.693, autotrophic yield coefficient Y(A) = 0.263, heterotrophic decay coefficient KdH, = 0.108 d(-1), autotrophic yield coefficient KdA = 0.089 d(-1), specific maximum COD removal rate v(mS), = 1.94 mg x (mg x d)(-1), half saturation constant for COD removal K(S) = 34.6 mg x L(-1), specific maximum ammonia removal rate vmN = 0.18 mg x (mg x d)(-1), half saturation constant for ammonia removal K(N) = 1.06 mg x L(-1). Compared with the normal reported data of conventional activated sludge process (CAS), Y(H), KdH obtained are higher and vmS, vmN are lower. The high sludge concentration condition of MBR process may account for those differences.