Spontaneous ignition of rubber woodchip in Thailand

The self-ignition temperature, the safe pile storage dimension and the activation energy of the rubber woodchip pile were determined by Frank-Kamenetskii approach. The woodchip samples with 278 kg/m3 and 458 kg/m3 of the bulk densities and 10.6% w.b. (wet basis) and 46.1% w.b. of the initial moisture contents were used. The samples were put into the cubic baskets with the widths of 8 cm, 10 cm, and 12 cm and placed in the well-ventilated oven. The results showed that the self-ignition temperatures were varied between 182 ◦C and 199 ◦C. The increase in the basket sizes decreased the self-ignition temperatures. The initial moisture content did not affect the self-ignition temperature. The dimension and shape of the rubber woodchip piles affect the self-ignition temperature. The size of the safe storage pile could be larger if the moisture content increased. The activation energy of the rubber woodchip ignition increased when the moisture content increased. The activation energies were 97.9 kJ/mol and 104.2 kJ/mol, for the moisture contents of 10.6% w.b. and 46.1% w.b., respectively.