Model setup and calibration. The reaction kinetic parameters of the V-SCR catalyst are calibrated to fit the experimental determined NOx, NH3 and N2O concentrations. The results of the NO and NH3 oxidation tests are presented in Figure 3. Oxidation of NO to NO2 is hardly detected even at high temperatures (Figure 3a). NH3 is mainly oxidized to N2 above 300°C and is almost fully oxidized at 500°C (Figure 3b). The same figures include the simulation model results after fitting the kinetic parameters. The model achieves a good agreement with the test results in the whole temperature range.
Model setup and calibration. The kinetic parameters of the Cu-SCR catalyst are adjusted to fit the experimentally determined NOx, NH3 and N2O concentrations. The outcomes of the NO and NH3 oxidation tests are depicted in Figure 8. The conversion of NO to NO2 is barely noticeable, especially at low temperatures (Figure 8a) and is activated above 300°C. NH3 is only oxidized to N2 above 250°C and is fully oxidized at 500°C (Figure 8b). Not any NO or N2O formation is observed during NH3 oxidation. The same figures also feature the simulation model results following the fitting of the reaction kinetic rate parameters. The model exhibits a strong agreement with the test results in the entire temperature window.
Model setup and calibration. The experimental results compared to the simulation model of the Pt-based oxidation catalyst are presented in Figure 13. Here the focus is not only on the conversion rate of NH3 as a function of temperature, but also on the unwanted NOx and N2O produced by the NH3 oxidation reactions. It is worth noting that the calibrated model is capable of capturing these complex trends with respect to NOx byproducts in the whole temperature range with good accuracy. The concentration of NH3 shows a steep decrease from 200°C to 250°C and is fully oxidized around 300°C. Above 200°C, N2O selectivity increases significantly with maximum concentration at 250°C that reaches 100 ppm. Selectivity to NO and NO2 is favoured above 250°C while N2O production is simultaneously decreasing.
Model setup and calibration. The kinetic parameters of the reaction rates were calibrated in order to fit the experimental data for NOx, NH3 and N2O. The results of the experimental data and the simulation model for the NO oxidation to NO2 and the oxidation of NH3 to N2 are presented in Figure 16a and Figure 16b respectively. The oxidation of NO is detected above 200°C with maximum oxidation around 450°C. NH3 is oxidized to N2 above 300°C, while not any NO or N2O formation was observed.
Model setup and calibration. In progress. Carollo completed the initial work required for this task in 2019 and 2020. The 2021 effort will include additional coordination and meetings with Plant staff and additional calibration as needed. Carollo will collect and review flow and water quality data and establish a list of scenarios to be evaluated. Carollo will establish the preliminary process model and demonstrate it during a process workshop to support scenario planning using the what-if and sensitivity analysis functions. Prior to detailed analysis and evaluation, Carollo will first establish a water and solids balance model for both WTPs as well as the relevant components of the distribution systems. The model will include source water and major liquid and solid stream treatment processes for the two plants. The Blue Plan-it® model will serve as an "intelligent process flow diagram" and uses historical turbidity and flow data; tracks flow and mass balance of the raw, treated streams, and residual streams; simulates organics, turbidity and total suspended solids removal by each water treatment process (including pre-sedimentation, final sedimentation, and filtration). The model will also include the WTP solids handling facilities including gravity thickeners, wash water clarifier, and mechanical dewatering or sludge lagoons. The model also includes chemical feeds used for coagulation, pH adjustment, preoxidation, taste and odor (e.g. PAC), and disinfection; and simulates the finished water quality.
