A large amount of rice straw is generated and left as much in paddy fields, which causes greenhouse gas
emissions as methane. Rice straw can be used as bioenergy. Rice straw pellets are a promising technology
because pelletization of rice straw is a form of mass and energy densification, which leads to a product
that is easy to handle, transport, store and utilize because of the increase in the bulk density. The operational
conditions required to produce high quality rice straw pellets have not been determined. This
study determined the optimal moisture content range required to produce rice straw pellets with high
yield ratio and high heating value, and also determined the influence of particle size and the forming temperature
on the yield ratio and durability of rice straw pellets. The optimal moisture content range was
between 13% and 20% under a forming temperature of 60 or 80 C. The optimal particle size was between
10 and 20 mm, considering the time and energy required for shredding, although the particle size did not
significantly affect the yield ratio and durability of the pellets. The optimized conditions provided high
quality rice straw pellets with nearly 90% yield ratio, P12 MJ/kg for the lower heating value, and >95%
durability.
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