Effect of particle size and addition of cocoa pod husk on the properties of sawdust and coal pellets

Abstract

The continuous increase of the world energy demand, the rise of fossil fuels costs, and the strong environmental policies around the globe are some of the reasons for the wood pellets industry increase. However, there are some other available biomass feedstocks capable of being densified for energy production. Among the various options, the use of mixed biomass pellets is becoming remark-able due to the wide variety of species, although more research is needed in order to enhance the mechanical properties of these pellets. This study aims to identify the effect of particle size on the mechanical properties of sawdust and coal pellets when cocoa pod husks are used as an additive. Cocoa pod husks have a similar composition to sawdust and less sulfur and nitrogen than coal. Thus, the use of this additive might decrease the environmental impact during coal pellets combustion. Results show an attractive potential of cocoa pod husks grinds for pellet production, an increase of the durability of coal pellets mixed with this raw material, and similar performance between cocoa pod husks and sawdust pellets. The compression ratio, the compressive and impact resistance varied linearly with the addition of cocoa pod husks.

Keywords

• Biomass
• coal
• cocoa pod husks
• densification
• pellets
• sawdust