Assessment of self-ignition risks of solid biofuels by thermal analysis

Storage of various types of biomass can result in spontaneous combustion processes, as they are capable of absorbing oxygen to produce exothermic oxidation reactions. Self-combustion is frequent in the storage and handling of biomass products and there are several factors related to their physical and chemical properties that influence their thermal susceptibility, that is, their tendency to oxidise and the subsequent ignition of the substance. Biomass from agriculture, forestry and waste origins with different chemical compositions are studied to analyse their behaviour and to determine the main factors that have an influence on the self-ignition risk. Among those factors, chemical composition, physical treatments and flammability characteristics are studied. Also thermal analysis methods are included in this study. Based on classical techniques of thermogravimetry and differential scanning calorimetry, particular experimental applications are used to assess the self-ignition risk of biomass products. Results are statistically analysed looking for correlations and grouping of samples. Statistical analysis concludes that the chemical composition of the biomass has an overriding role in characterising the self-ignition tendency of these biomasses. (C) 2014 Elsevier Ltd. All rights reserved.