E-Andrew Sindt Creative Component S11.pdf

could be due to the reduced nitrite oxidation or possibly the observed denitrification was better thansimulated, or some combination of both was present.The observed effluent TP concentration was much higher than that simulated. This could be due tosomething inhibiting PAOs that is currently not accounted for in the simulator. The over-prediction ofeffluent TP could also be due in part to the way the simulator handles the significantly higher RBCODfraction determined by the influent specifier. This possibility of RBCOD fraction affecting effluent TPconcentrations is investigated further in sub-section 4.5.2.Total nitrogen, the effluent parameter that was most difficult to adjust in regular mode, was alreadywell within the 20% margin for error at 11.4% for default simulator parameter values for the BNR-S1 SBRmode.Table 4.4- BNR-S1 mode effluent quality for default simulator parameter settingsTSS pH cBOD TN NH 3-N NO - 2 -N NO - 3 -N TP COD F. CODObserved (mg/L) 7.9 6.9 - 6.6 1.4 1.3 2.6 1.5 - 29.3Default (mg/L) 5.6 7.0 3.4 7.4 0.3 0.1 4.7 0.3 40.1 33.3% deviation -29.3 1.9 11.4 -75.5 -89.6 81.0 -78.9 13.7Table 4.5 compares observed effluent quality for the BNR-S1 mode to predicted effluent quality for theBNR-S1 mode using the regular mode calibrated simulator parameter values. Improvements fromdefault predictions were made to TSS, NO 2 - , TP and filtered COD. Regular mode calibrated simulatorparameters created increased deviations from observed values in TN and NO 3 - .Table 5.5- BNR-S1 mode effluent quality with calibrated regular mode simulator parametersTSS pH cBOD TN NH3-N NO2-N NO3-N TP COD F. CODObserved (mg/L) 7.9 6.9 - 6.6 1.4 1.3 2.6 1.5 - 29.3regular mode calibration (mg/L) 8.9 7.0 3.9 11.4 0.7 1.7 6.6 1.1 42.3 31.9% deviation 12.2 1.4 72.4 -47.8 29.8 153.7 -25.1 8.9Calibration of the BNR-S1 mode built upon the calibration of the regular mode in that the first step ofthe BNR-S1 mode calibration was to optimize the settings for OHO yield and NOB and AOB maximumspecific growth rate (Figure 4.15). Similar to the regular mode, these three parameters had the mostsignificant effects on the largest number of effluent parameters. Side effects of simulator parameteradjustment were greatly reduced by optimizing these three first before adjusting the simulatorparameters with more targeted effects. The simulator parameters that yielded more targeted effluentparameter concentration changes and the effluent parameter they target include maximum Vesilindsettling velocity for effluent TSS, AOB substrate half-saturation concentration for effluent NH 3 , andaerobic P/PHA uptake for effluent TP.57