# Sugarcane Bagasse Torrefraction for Fluidized Bed Gasification
## 4 Results and Discussion
### Improving Energy Properties of Sugarcane Bagasse by Torrefaction
\begin{table}
\begin{tabular}{c c c c} \hline \hline  & & \multicolumn{3}{c}{**Torrefaction Time (min)**} \\
**Property** & **Raw Bagasse** & **30** & **45** \\ \hline Volatiles (\%) & 88.48 & 85.67 & 85.71 \\ Ash (\%) & 2.11 & 5.97 & 5.48 \\ Fixed Carbon (\%) & 9.41 & 8.36 & 8.81 \\ C (\%) & 41.45 & 47.07 & 46.90 \\ H (\%) & 5.514 & 6.02 & 6.02 \\ O (\%) \({}^{\ast}\) & 50.37 & 40.62 & 41.21 \\ N (\%) & 0.509 & 0.28 & 0.33 \\ C/O & 0.823 & 1.159 & 1.138 \\ H/C & 0.133 & 0.128 & 0.128 \\ Increase C/O ratio (\%) & - & 40.82 & 38.29 \\ Decrease H/C ratio (\%) & - & 3.75 & 3.75 \\ Higher heating value (HHV) (M)/kg product & 15.96 & 19.19 & 19.08 \\ Mass yield DAF (\%) & - & 82.21 & 81.03 \\ Energy yield DAF (\%) & - & 98.85 & 96.87 \\ Energy density (\% Energy yield/\% Mass yield) & - & 1.20 & 1.19 \\ Rise in HHV (\%) & - & 20.24 & 19.55 \\ \hline \hline \end{tabular} \({}^{\ast}\) by difference.  
\end{table} 
Table 4: The proximal and ultimate composition of torrefied sugarcane bagasse at 230 \({}^{\circ}\)C. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & & \multicolumn{3}{c}{**Torrefaction Time (min)**} \\
**Property** & **Raw Bagasse** & **30** & **45** \\ \hline Volatiles (\%) & 88.48 & 81.32 & 79.47 \\ Ash (\%) & 2.11 & 6.34 & 5.32 \\ Fixed Carbon (\%) & 9.41 & 12.34 & 15.21 \\ C (\%) & 41.45 & 48.20 & 49.53 \\ H (\%) & 5.51 & 6.08 & 5.94 \\ O (\%) \({}^{\ast}\) & 50.37 & 39.04 & 39.16 \\ N (\%) & 0.51 & 0.29 & 0.01 \\ C/O & 0.82 & 1.24 & 1.27 \\ H/C & 0.133 & 0.126 & 0.120 \\ Increase C/O ratio (\%) & - & 50.05 & 53.71 \\ Decrease H/C ratio (\%) & - & 5.26 & 9.77 \\ Higher heating value (HHV) (M)/kg product & 15.96 & 19.81 & 20.12 \\ Mass yield DAF (\%) & - & 71.01 & 72.60 \\ Energy yield DAF (\%) & - & 88.10 & 91.41 \\ Energy density (\% Energy yield/\% Mass yield) & - & 1.24 & 1.26 \\ Rise in HHV (\%) & - & 24.11 & 26.05 \\ \hline \hline \end{tabular} \({}^{\ast}\) by difference.  
\end{table} 
Table 5: The proximal and ultimate composition of torrefied sugarcane bagasse at 280 \({}^{\circ}\)C.  
For the residence time of 45 min, the fixed carbon has the same behavior for the temperature of 230 \({}^{\circ}\)C, but with a more significant increment for 280 \({}^{\circ}\)C. Ash content showed the primary increment for the temperature of 230 \({}^{\circ}\)C, with the same tendency for the temperature increase for the residence time of 30 min; ash remains almost in its totality in the solid product of the torrefaction. On the other hand, the tendency is slightly reverted for the residence time of 45 min. The higher heating value shows a similar trend for both residence times, opposite to volatiles and fixed carbon, with the lower increments at the temperature of 280 \({}^{\circ}\)C for both residence times. Figure 3-III presents the variation of fuel properties with residence time increase for the temperature of 230 \({}^{\circ}\)C. Figure 3-IV presents the same effects for the temperature of 280 \({}^{\circ}\)C. For the temperature of 230 \({}^{\circ}\)C, no significant variation is observed after the obtained composition at 30 min. Conversely, for 280 \({}^{\circ}\)C, a substantial enhancement is observed for the fixed carbon content after 30 min. The torrefaction process also causes a noticeable reduction of the volatiles and ash composition for a residence time of 45 min, compared with the obtained composition at 30 min. A slight increment of the higher heating value is observed for a residence time of 45 min. Figure 4 shows the effects on sugarcane bagasse elemental composition of studied torrefaction temperatures and residence times. Figure 4-I presents the carbon, hydrogen, and nitrogen composition at different temperatures, for the residence time of 30 min. Figure 4-II presents the same results for a residence time of 45 min. Figure 3: Effects of torrefaction temperatures (**I,II**) and residence times (**III,IV**) on proximate analysis of sugarcane bagasse. The elemental composition has the same behavior for both residence times when the temperature increases.