# Flue Gas Composition and Treatment Potential of a Waste Incineration Plant
## 3 Results  
### Model Calculations  
A set of the model equations was used to find the volumetric flow rate of the flue gas, the excess air needed, and the gas fractions forming the flue gas itself. The results from this model were compared with the results achieved by Epsilon as a first step in the design of the proposed flue gas cleaning system. The reason for using this equation model and inserting the governing parameters of the suggested waste incineration plant was to validate Epsilon's results and to build a comprehensive emission calculation model that can be used easily and for free. However, careful consideration must be given to specifying the constitution of the elements of the waste and the capacity of the incineration facility. The findings showed that the results from the equations model were close to Epsilon's. Furthermore, Equations (2) and (4) perfectly matched the mass flowrate of air in Epsilon's and could be considered for the calculation of air mass flow required for the incineration of MSW. The CO\({}_{2}\) specification methodology also matched Epsilon's results, where the percentage of CO\({}_{2}\) was calculated as a function of O\({}_{2}\). These matches were validated for different values of excess air ratios and different MSW mass flows. In all cases, the results from the calculated air mass flow, oxygen volume, and CO\({}_{2}\) percentage matched Epsilon's results.  
Note: O\({}_{2}\) volume must still be divided by the calculated flue gas volumetric flowrate to get the percentage of O\({}_{2}\). According to the calculation model, the theoretical flue gas volumetric flow rate was 2.55 m\({}^{3}\)/kg for 25 kg/s with MSW mass flow and an excess air ratio of 1.5. Thus, the percentage of O\({}_{2}\) in the flue gas volume was around 5%. The source of water vapor in the flue gas was attributed to the presence of water content in the MSW, meaning that dry air was considered (see Figure 4). To validate this calculation model with the results from Epsilon, the governing parameters of the emission fractions (mass flow of MSW and excess air ratio) were checked for each step change as seen in Table 10. As can be seen from the model calculations, the CO\({}_{2}\) volume had the major fraction of the flue gas volume constitution at around 21%, which makes sense since carbon formed around 11% of the combustible fraction of the analyzed sample of MSW taken in Jordan. At the same time, the SO\({}_{2}\) volume and N\({}_{2}\) had the lowest contribution in the flue gas volume with 0.00035 and 1.48%, respectively.  
The findings from both methodologies (model equations and Epsilon) showed approximately the same results for O\({}_{2}\), CO\({}_{2}\), volumes in flue gas, and air mass flow as required in the furnace. Any deviations in the results were small. The volume portions of O\({}_{2}\) and CO\({}_{2}\) were not affected by the change in the mass flow of the MSW, but did change with the excess air ratio. The volume of CO\({}_{2}\) decreased when the excess air ratio increased, and as previously mentioned, this is what should happen. The mass flow rate of air required to achieve the combustion process in the furnace was affected by both the excess air ratio and the MSW mass flow. The air mass flow rate was proportional to the excess air ratio and the MSW mass flow. This makes sense, as increasing the mass flow of MSW requires more excess air to match the increment in the MSW loaded into the furnace which requires an increase in the amount of air pumped into the furnace (air mass flow) and vice versa. The results from the model equations can be considered and adapted for the pre-design steps of any waste incineration plant to be erected when the MSW composition (elementary analysis), LCV, and plant capacity are specified.