SBR Technology

The Sequencing Batch Reactor (SBR) is a fill-and-draw activated sludge system that operates in time-based cycles (typically 4-8 hour cycles) rather than using separate tanks for each treatment stage. All biological treatment, settling, and decanting occur in a single reactor vessel, reducing footprint by 40-60% compared to conventional continuous-flow systems while achieving superior effluent quality (BOD/COD removal >95%, ammonia removal >90%, phosphorus removal >80%).

SBR technology operates through five distinct, programmable stages: Fill (30-50% of cycle time), React (30-40% with aeration), Settle (15-25% quiescent settling), Decant (5-10% effluent removal), and Idle (sludge wasting and preparation). This sequencing allows complete nitrification-denitrification and biological phosphorus removal in a single tank by alternating aerobic, anoxic, and anaerobic conditions. Typical volumetric loading rates of 0.3-0.6 kg BOD/m³/day with MLSS concentrations of 3,000-5,000 mg/L ensure robust treatment performance.

This batch-wise approach provides exceptional operational flexibility, allowing operators to easily adjust cycle times (from 3 to 12 hours), aeration intensity, and fill patterns to accommodate varying influent loads (handling 2-3x design flow surges), seasonal variations, and changing effluent standards without physical modifications. Energy consumption typically ranges from 0.6-1.2 kWh/m³ treated, with 20-30% lower operational costs than conventional activated sludge systems due to the elimination of return sludge pumping and separate clarifiers.