## 3 Results  
### Physical Properties  
The particle density of the briquettes showed statistically significant differences (\(p\leq 0.05\)) among treatments (Table 3). The Kruskal-Wallis test (\(p<0.05\)) presented four statistically homogeneous groups, with T3 (0:0:100) constituting the first; this was different from all treatments and had the highest particle density (1.02 g cm\({}^{-3}\)). Values ranged from 0.9 to 1.0 g/cm\({}^{3}\) with T0 (12:71:17), which showed no differences with T4 (33:33:33), but also with neither T2 (0:100:0) nor T6 (67:0:33). T7 (0:67:33), T8 (0:33:67), T6 (67:0:33), T4 (33:33:33), and T2 (0:100:0) were all in statistical group two. Group three included T9 (33:67:0) and T5 (67:33:00). The treatments with the lowest density and grouped into statistical group four were T1 (100:0:0) (0.92 g/cm\({}^{3}\)) and T10 (33:0:67).  
Volumetric swelling of briquettes showed significant statistical differences (\(p\leq 0.05\)) among treatments (Table 3). The Kruskal-Wallis test (\(p<0.05\)) presented two statistically homogeneous groups. The first group was formed by treatment T7 (0:67:33) (3.9%) with the highest volumetric swelling, which registered no statistically significant differences (\(p>0.05\)) with T2 (0:100:0), T3 (0:0:100), T8 (0:33:67), or T10 (33:0:67). In contrast, treatment T5 (67:33:0) showed the lowest volumetric swelling (1%), followed by T6 (67:0:33) and T4 (33:33:33), with 1.6%. These were all grouped into statistical group two because there were no significant statistical differences (\(p>0.05\)) among them.  
Figure 3: Simplex reticular design (3, 3) (Elaborated from [PERSON] and [PERSON] [17]).  
\begin{table}
\begin{tabular}{l c c c c c c c c c c c c c c} \hline \hline  & \multicolumn{2}{c}{**Particle Density**} & \multicolumn{2}{c}{**Volumetric Swelling**} & \multicolumn{2}{c}{**Compression**} & \multicolumn{2}{c}{**Impact Resistance**} & \multicolumn{2}{c}{**Gross Calorific Value**} \\
**Treatment** & \multicolumn{2}{c}{**(g cm\({}^{-3}\))**} & \multicolumn{2}{c}{**(\%)**} & \multicolumn{2}{c}{**Resistance (N mm\({}^{-2}\))**} & \multicolumn{2}{c}{**Index (\%)**} & \multicolumn{2}{c}{**(MJ kg\({}^{-1}\))**} \\ \cline{2-13}
**(Mixture)** & \multicolumn{2}{c}{**Mean**} & \multicolumn{2}{c}{**Std.**} & \multicolumn{2}{c}{**Mean**} & \multicolumn{2}{c}{**Std.**} & \multicolumn{2}{c}{**Mean**} & \multicolumn{2}{c}{**Std.**} & \multicolumn{2}{c}{**Mean**} & \multicolumn{2}{c}{**Std.**} \\ \hline T0 (12-71-17) & 1.00 & 0.01 & b * & 1.86 & 0.78 & b & 29.06 & 1.63 & bc & 76.67 & 20.00 & ab & 19.93 & 0.26 & c \\ T1 (100-0-0) & 0.92 & 0.01 & f & 2.01 & 1.49 & b & 18.45 & 1.05 & e & 53.33 & 6.67 & c & 21.63 & 0.13 & a \\ T2 (0-100-0) & 0.99 & 0.02 & c & 3.75 & 1.17 & a & 26.13 & 3.61 & bcd & 100.00 & 51.64 & a & 20.11 & 0.04 & bc \\ T3 (0-100-100) & 1.01 & a & 3.00 & 0.45 & a & 37.09 & 2.51 & a & 99.73 & 0.37 & a & 19.48 & 0.15 & d \\ T4 (33-33-33) & 0.99 & 0.01 & bc & 1.63 & 0.99 & bc & 28.06 & 2.79 & bcd & 93.33 & 13.33 & a & 19.53 & 0.09 & d \\ T5 (67-33-0) & 0.96 & 0.01 & e & 0.96 & 0.61 & c & 24.53 & 2.89 & bcd & 60.00 & 8.16 & bc & 20.51 & 0.32 & abc \\ T6 (67-03-03) & 0.98 & 0.01 & cd & 1.57 & 0.86 & bc & 29.24 & 1.88 & bc & 76.67 & 20.00 & a, b & 19.44 & 0.22 & d \\ T7 (0-67-33-67) & 0.97 & 0.01 & d & 3.95 & 1.21 & a & 23.35 & 1.31 & cdc & 106.67 & 48.99 & a & 19.82 & 0.04 & c \\ T8 (0-33-67) & 0.98 & 0.01 & d & 3.45 & 0.75 & a & 25.66 & 2.57 & bcd & 86.67 & 16.33 & a & 19.35 & 0.18 & d \\ T9 (33-67-0) & 0.96 & 0.01 & e & 1.77 & 1.07 & bc & 22.71 & 3.33 & de & 93.33 & 56.37 & a & 20.99 & 0.13 & ab \\ T10 (33-0-67) & 0.94 & 0.01 & f & 2.99 & 1.18 & a & 23.48 & 1.06 & cde & 73.33 & 13.33 & abc & 19.54 & 0.10 & d \\ \hline \hline \end{tabular}
* * Different lowercase letters on a column indicate statistically significant differences among treatments based on the Tukey or Kruskal-Wallis tests (\(p<0.05\)).  
\end{table}
Table 3: Means and standard deviations of physical, mechanical, and energy properties of briquettes produced with different percentages of sawdust particle sizes.