# Energy Recovery via Thermal Gasification from Waste Insulation Electrical Cables (WIEC)
## 4 Results
### Controlled Gasification Syngas Composition  
In the gasification tests, the samples were taken at 60, 120, and 180 min, as a criterion and in order to be able to observe the evolution of the synthesis gas produced, until the process stabilized. It should be noted that the temperature of the first sample (60 min) is constantly low, it is still a transitory phase of the process, when the temperature is rising. In the second sample, the temperature of the process is still rising, however, the inertia of the equipment is much lower, and the stabilization of the process is more noticeable, not extinguishing a large amount of oxidizing agent, as in the first sample. The third sample is considered to be the stabilization of the process, where the temperature variation is zero or nearly zero. As previously mentioned, the temperature sensors are welded on the outer wall of the reactor, for this reason, the oxidation and reduction temperatures may appear to be lower as compared with a normal gasification process.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c} \hline  & \multicolumn{6}{c}{**100:0**} & \multicolumn{6}{c}{**90:00**} & \multicolumn{6}{c}{**80:20**} & \multicolumn{6}{c}{**70:30**} \\ \hline
**Parameters** & **Units** & **Sample  
Figure 2 illustrates the composition of syngas produced for each experiment. In fact, the WIEC content is responsible for the difference in temperature distribution in the reactor throughout the tests, which is reflected in the syngas composition. It is possible to observe that the temperature increases with an increase in the percentage of WIEC, due to large amounts of volatiles. The volatiles are released as the temperature increases; for lignocellulosic biomass, the devolatilization occurs at higher temperatures, around 500 \({}^{\circ}\)C. WIEC have higher amounts of volatiles that require lower temperatures to devolatilize, which increases temperatures during the thermochemical process. A positive impact is observed with an increase in WIEC on the behavior of the temperature and in the concentrations of H\({}_{2}\) and CO, while other studies have also reported a decrease in CO\({}_{2}\) concentration and an increase in H\({}_{2}\) concentration with higher proportions of polymeric residues in mixtures with pine [36]. The test performed with a mixture of 30% WIEC presented higher temperatures in the combustion and reduction zones and concentrations of H\({}_{2}\) of 17.7% and CO of 20.5%, originating a syngas with a HHV of 5.18 MJ/m\({}^{3}\). Another study by [PERSON] et al. determined an alternative influence with a mixture of lignocellulosic and plastic fuels and concluded that the chars derived from the lignocellulosic fuel absorbed the volatiles of the polymeric fuel, and therefore promoted the cracking of these hydrocarbons. The polymeric radicals acted as H contributors that balanced the radicals formed by the lignocellulosic fuel [37]. These mixtures, contrary to expectations, produced a reduced number of light hydrocarbons, and increased the concentration of CO and H\({}_{2}\). The quality of the syngas is indicative of improved catalytic reform. These results may be related to the formation of lignocellulosic fuel chars.  
With an increase in the percentage of WIEC, and the consequent increase in the reactor temperature, it is possible to observe that the Boudouard reaction (C + CO\({}_{2}\Leftrightarrow\) 2 CO) of CO is favored and, additionally, light hydrocarbons suffer cracking reactions at high temperatures favoring H\({}_{2}\) formation.