## 3 Results
### Proximate Analysis, Physical, Mechanical, and Energy Characteristics of Agro-Pellets  
Volatile material and fixed carbon of agro-pellets showed statistical differences among mixtures (\(p<0.05\)); values ranged from 83.95 to 91.86% and 7.83 to 15.54%, respectively (Table 1). Moisture content and ash content did not show statistical differences (\(p>0.05\)); they varied in the ranges 5.58-6.77% and 0.44-0.58%, respectively. The bulk density, particle density, compression ratio, impact resistance index, and gross calorific values differed significantly (\(p<0.05\)) among mixtures, presenting the ranges 550-680 Kg m\({}^{-3}\), 1090-1340 Kg m\({}^{-3}\), 3.28-4.74, 105.5-157.5, and 18.84-22.31 (MJ/Kg), respectively (Table 2). Gross calorific values showed statistical differences among mixtures and the values ranged from 18.84 to 22.31 MJ Kg\({}^{-1}\) (Table 2). \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Bionass Mixtures** & \multicolumn{6}{c}{**Oil Palm Residues:Pine Sawdust Mixtures**} \\ \cline{2-7}
**Characteristics** & **100:0** & **80:20** & **60:40** & **40:60** & **20:80** & **0:100** \\ \hline \multicolumn{7}{c}{**Structural compounds and extracts**} \\ Cellulose (\%) & 46.28 (1.13) & 44.16 (1.18) & 45.82 (0.49) & 47.85 (0.14) & 50.64 (0.44) & 56.64 (0.06) \\ Hemicellulose (\%) & 18.81 (0.49) & 18.58 (0.16) & 17.33 (0.63) & 15.92 (0.29) & 14.56 (0.12) & 14.14 (0.20) \\ Lignin (\%) & 13.90 (0.80) & 15.09 (0.90) & 18.73 (0.25) & 20.97 (0.32) & 23.68 (0.25) & 25.02 (0.27) \\ Extracts (\%) & 21.01 (0.65) & 22.17 (0.45) & 18.12 (0.63) & 15.26 (0.44) & 11.12 (0.50) & 4.20 (0.43) \\ \multicolumn{7}{c}{**Proximate analysis**} \\ Moisture content (\%) & 7.58 (0.03) * & 9.84 (0.047) & 9.28 (0.11) & 8.88 (0.18) & 7.66 (0.32) & 10.14 (0.09) \\ Volatile material (\%) & 83.95 (1.98) & 88.75 (1.70) & 87.01 (1.26) & 88.91 (1.99) & 91.86 (1.27) & 88.83 (1.64) \\ Ash (\%) & 0.51 (0.57) & 0.38 (0.05) & 0.36 (0.33) & 0.35 (0.03) & 0.31 (0.03) & 0.36 (0.05) \\ Fixed carbon (\%) & 15.54 (1.92) & 10.86 (1.72) & 12.63 (1.29) & 10.73 (1.97) & 7.83 (1.30) & 10.81 (1.66) \\ \multicolumn{7}{c}{**Physical properties**} \\ Bulk density (g/cm\({}^{3}\)) & 0.12 (0.01) & 0.15 (0.01) & 0.17 (0.01) & 0.20 (0.01) & 0.21 (0.01) & 0.20 (0.01) \\ \hline \hline \end{tabular}
* Statistical significant (\(p<0.05\)), values in parentheses represent the standard deviation.  
\end{table} 
Table 1: Chemical characteristics, proximate analysis, and bulk density of oil palm residues:pine sawdust biomass mixtures. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Pellets Characteristics** & \multicolumn{6}{c}{**Oil Palm Residues:Pine Sawdust Mixtures**} \\ \cline{2-7}  & **100:0** & **80:20** & **60:40** & **40:00** & **20:80** & **0:100** \\ \hline \multicolumn{7}{c}{**Proximate analysis**} \\ Moisture content (\%) & 6.45 (0.26) & 5.83 (0.17) & 6.77 (0.07) & 6.76 (0.89) & 5.84 (9.19) & 5.58 (0.42) \\ Material volatile (\%) & 79.40 (1.90) & 80.04 (1.47) & 80.41 (1.02) & 87.32 (1.92) & 85.68 (1.63) & 89.31 (3.68) \\ Ash (\%) & 0.54 (0.07) & 0.54 (0.05) & 0.58 (0.04) & 0.44 (0.11) & 0.53 (0.07) & 0.44 (0.08) \\ Fixed carbon (\%) & 20.05 (1.83) & 19.42 (1.42) & 19.01 (0.98) & 12.23 (1.81) & 13.79 (1.57) & 10.25 (3.60) \\ \multicolumn{7}{c}{**Physical and mechanical properties**} \\ Bulk density (Kg m\({}^{3}\)) & 540 (170) & 610 (10) & 640 (10) & 660 (10) & 680 (10) & 670 (10) \\ Particle density (Kg m\({}^{3}\)) & 1180 (230) & 1240 (220) & 1190 (270) & 1250 (370) & 1090 (240) & 1340 (520) \\ Compression ratio & 4.74 & 4.13 & 3.74b & 3.29 & 3.28 & 3.29 \\ Impact resistance index & 158 (65.44) & 155 (78.89) & 144 (72.75) & 114 (28.65) & 126 (50.31) & 108 (27.02) \\ \multicolumn{7}{c}{**Energy properties**} \\ Gross calorific value & 21.89 (0.16) & 22.31 (0.02) & 21.19 (0.47) & 20.75 (0.06) & 19.70 (0.13) & 18.84 (0.48) \\ \hline \hline \end{tabular}  
* Values in parentheses represent the standard deviation.  
\end{table}