Buffering effects of shock loads in sequencing batch reactor

In this study, we investigated the buffering effect with different COD, NH4+-N and TP shock loads on the performance of lab-scale Sequencing Batch Reactor(SBR) using synthetic wastewater. This study was operated under the following conditions : HRT, 12 hrs : MLSS, 2,000 mg/L : F/M ratio, 0.2 kgCOD/kgMLSSㆍd : SRT, 20days, and was increased by a factor, COD : ranging from 200-2000 mg/L, NH4+-N : ranging from 30-300 mg/L, T-P : ranging from 5-50 mg/L in the reactor. As results, COD removal rate at different shock loads was decreased until 42.1%(stable state : 95%) and concentration with effluent was higher than 695 mg/L(at Run 6). In case of NH4+-N removal rate was decreased until 35.8% from 97.0% and also T-P removal rate was decreased until 5.0%. Effluent concentrations of COD, NH4+-N and T-P were rapidly increased according to shock loads and needed 3, 4 and 6 additional cycle times for recovering the stable condition.