Our aim was to identify the potential of rice straw (RS) and rice husk (RH) as raw materials for pellet production. Compared to woody biomass, RS and RH can be easily dried, but contain significant levels of ash. Higher heating values of oven-dried RS and RH are slightly lower than those of commercial wood pellets. RS and RH contain substantially more silicon, potassium and calcium than larch sawdust. However, ash and moisture contents of RS was significantly reduced following a 15-week exposure period on rice paddy. These results suggest that RS and RH present suitable alternatives to wood as raw materials for pellet production due to their availability, relatively high calorific value and low moisture content. The durability of RS and RH pellets improved steadily with increasing pelletizing temperature and time. Pelletization under appropriate conditions also enabled the durability and bulk density of RS and RH to be improved, enhancing their potential as alternative combustion fuels.
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