Work out sbr cycle time instantly with clear inputs, formula shown and shareable results.
A sequencing batch reactor cycles through fill, react, settle, decant and idle in one tank. Total cycle time determines how many batches a day each tank handles and therefore the volume it can treat. Typical cycles are 4-8 hours, with the react phase split into anoxic and aerobic sub-phases for nutrient removal.
Cycle time
Cycle = fill + react + settle + decant and idle
Throughput
Cycles per day = 1440 / cycle time in minutes
At least two so one can accept flow while the other settles and decants, unless upstream balancing storage is provided. Three or more gives smoother operation and redundancy.
Decanting must draw clarified supernatant without disturbing the blanket. Insufficient settle time carries solids over; excessive settle time wastes cycle capacity and can trigger denitrification and rising sludge.