Application of hydrochar as binding material for enhanced fuel properties of torrefied biomass pallets

Abstract

This study aimed to improve the physical and mechanical properties of pellets produced from torrefied sugarcane leaves blended with hydrochar as a binder. The hydrochar was obtained through hydrothermal carbonization of sugarcane leaves. Pellets were produced from blends of torrefied biomass with hydrochar in different ratios. The results showed that adding 10– 50% of the binder significantly increased density and compressive strength of the torrefied pellets. Single pellet density ranged from 1,059.2 kg/m3 to 1,135.5 kg/m3 , while compressive strength increased by 58–160%. The addition of hydrochar also decreased ash content (3.4–25.2%) and reduced sulfur and nitrogen contents (6–28% and 3–16%, respectively). Optimal conditions for pelletizing were determined at 70/30 proportions of torrefied biomass and binder. The resulting pellets had 10.8% ash content, 9.20% moisture content, 1,111.2 kg/m3 single pellet density, 6.66 MPa compressive strength, and 18.37 MJ/kg lower heating value. These findings demonstrate the potential of incorporating hydrochar as a binder to improve the properties of torrefied biomass pellets.

Keywords

• hydrochar
• torrefied pellet
• compressive strength
• torrefaction
• binder