Design and Modeling of Post-Denitrification Single-Sludge Activated Sludge Processes

A step-by-step design approach for sizing oxic/anoxic single- sludge activated sludge systems is presented. A computer model utilizing a Lotus 1–2–3 spreadsheet was also developed which simulates the post- denitrification single-sludge activated sludge process. The biokinetic equations developed by Lawrence and McCarty are utilized in the model. The model was calibrated using data from a full-scale, modified pure oxygen activated sludge process operating in the oxic/anoxic mode. Two- tailed, paired comparison student ‘t-tests’ performed on effluent BOD₅, SS, TKN, NH₃-N, NO^- ₃-N, and TN indicated there was no significant difference between the actual effluent values and that predicted by the model at a 99 percent confidence level.