Optimization of the step feeding ratio for nitrogen removal by SBR using technique for order preference by similarity to ideal solution (TOPSIS)

The performance of nitrogen (N) removal was investigated by altering the influent step feeding in a sequencing batch reactor (SBR). optimum condition for analyzed using Technique Order Preference Similarity to Ideal Solution (TOPSIS) with entropy weight method, considering C/N ratio range 1.5 4.5. results showed that SBR multi-step-feeding system achieved high rate 92.7% at three-step mode. Nitrogen significantly improved due multi-step feeding, which provided required carbon source anoxic phase nitrate enhanced denitrification process. highest real-time operation observed mode 60% primary 30% secondary and 10% tertiary respectively. TOPSIS analysis also identical SBR.