# Flue Gas Composition and Treatment Potential of a Waste Incineration Plant
## 2 Methods and Materials
### CO\({}_{2}\) Emissions and Capturing  
A comprehensive economy requires an enormous amount of energy, which is primarily produced by the combustion of fossil fuels. Many different chemical compounds are released accompanied by the synthesis gas produced from the combustion of fuel, the most concerning of which is CO\({}_{2}\). Carbon dioxide emissions are considered a significant negative side effect of this activity. The cumulative emission of CO\({}_{2}\) contributes to climate change and is considered to be the greatest single contributor to the greenhouse effect [6]. Waste incineration plants are definitely emitting CO\({}_{2}\). Epsilon's intensive numerical model measures the emissions generated according to the designed MSW flow rate capacity of plants. It is worth mentioning here that the average concentration of CO\({}_{2}\) in the Earth's atmosphere in 2018 was 407 ppm, which is about 40% higher than in the preindustrial age [30]. Therefore, worldwide efforts to reduce CO\({}_{2}\) emissions are important for both the global economy and the environment. In the past decades, many technologies and  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Emission Limit mg/Nm\({}^{3}\) Dry** & **IED 2010** & **BREF 2018** \\ \multicolumn{3}{c}{**(Corrected at 11\% O\({}_{2}\))**} \\ \hline SO\({}_{2}\) daily average & 50 & 5–30 \\ HCl daily average & 10 & 2 to 6 \\ HF daily average & 1 & 1\(<\) \\ Dust & - & \(<\)2–5 \\ Cd + TI & - & 0.005–0.02 \\ Sb +As + Pb + Cr + Co + Cu + Mn + & - & 0.01–0.3 \\ Ni + V & - & \\ \hline \hline \end{tabular}
\end{table}
Table 9: Evolution of the emission limit value for waste incineration between the industrial emission directive (IED) and the latest waste incineration (WI) best available technique reference (BREF) document (for heavy metals the average is taken over the sampling period) [29].  
methodologies appear to have helped to achieve this goal. A summarized definition of three technologies with the highest maturity levels is shown in Appendix A.  
However, in this study, it was assumed that carbon particles were already activated and injected in the stream flow of the flue gas of the simulated plant. It must be remembered that the temperature of the flue gas has to be decreased as much as possible before it enters the separation process of the CO\({}_{2}\) unit. It was noticed from the available data in [30] that the adsorption efficiency of CO\({}_{2}\) emissions increased by decreasing the temperature. The adsorption process decreased by 25-30% for each gram of activated carbon when the temperature of the reaction increased from 0 \({}^{\circ}\)C to 25 \({}^{\circ}\)C at constant pressure.  
MSW landfilling is also a major source of methane emissions in the form of landfill gas. Methane is 25 times more potent of a greenhouse gas than CO\({}_{2}\). WTe plants avoid the formation of landfill gas by incinerating the organic methane-producing compounds in MSW and can, therefore, improve net emissions savings.  
According to the inserted data in Epsilon regarding the MSW composition and combustion chamber properties, the flue gas volumetric flow was around 760 m\({}^{3}\)/s, and the CO\({}_{2}\) emissions was around 117,715 ppm, equivalent to 0.2 kg/m\({}^{3}\), which means that there was approximately 152 kg/s for the mass flow of CO\({}_{2}\). It could be concluded that each kg of incinerated MSW generates 30 m\({}^{3}\) of flue gas and that this volumetric flow holds around 6 kg of CO\({}_{2}\). This amount is directly related to the combustion chamber zone.