Evaluating the Potential of Nutrient Amendment and Bioaugmentation to Improve Secondary Treatment Efficiency in Bench Scale Aerated Stabilization Basins

Sufficient macronutrients are critical for biological wastewater treatment, especially in aerated stabilization basins (ASBs), which require continuous bacterial synthesis. However, it is not usually practical to add theoretical nutrient requirements, due to the cost of nutrients and concerns about effluent nutrient concentrations. Bioaugmentation, or the addition of viable bacteria to the system, has been observed to reduce the nutrient requirements in aerated stabilization basins. A bench-scale aerated stabilization basin study was performed to confirm the benefits of bioaugmentation. Six reactors were fed Kraft paper mill wastewater, along with high or low doses of ammonia polyphosphate blends and bioaugmentation/no bioaugmentation. Over the course of the study, all reactors that received supplemental nutrients or bioaugmentation showed better biochemical oxygen demand (BOD) removal than the control reactor, and the reactor that received high nutrient showed similar BOD removal compared to the reactor that received low nutrient and bioaugmentation.