Efficiency of SBR Process with a Six Sequence Aerobic-Anaerobic Cycle for Phosphorus and Organic Material Removal from Municipal Wastewater

Various chemical, physical and biologic treatment methods are being used to remove nitrogen and phosphorus from wastewater. Sequencing batch reactor (SBR) is a modified activated sludge process that removes phosphorus and organic material from sanitary wastewater, biologically.
This study was conducted in 2016.The performance of an aerobic-anaerobic SBR pilot device, located at Ahwaz West Wastewater Treatment Plant, Ahwaz, southern Iran in phosphorus and organic material removal was evaluated to determine the effect of the aerobic-anaerobic step time on the efficiency of nitrogen and phosphorus removal, the effect of changing the sequence of steps and the effect of time ratio on phosphorus removal efficiency. A reactor of 8 L was used. Influent contained 397 and 10.7 mg/l COD and phosphorus, respectively. The pilot plant started with a 24 h cycle including four cycles of 6 h, as follows: 1- Loading (15 min), 2-Anaerobic (2 h)-Aerobic (2 h), 3- Settling (1 h), Idleness (30 min) and 5- decant (15 min).
After reaching steady conditions (6 months), Removal percentages of phosphorus, BOD5, COD, and TSS in The SBR over a period of 6 months was 79%, 86%, 89% and 83%, respectively.
Result of this study can be used for designing and optimum operation of sequencing batch reactors.