An exploratory study of explosion potential of dust from torrefied biomass

Abstract

Torrefaction makes biomass brittle, and as such it is likely to produce more dusts during handling and transportation. So, it could increase the risk of explosion in plant using torrefied biomass. As the torrefaction technology enters commercial market the safety aspect of torrefied wood becomes important. The present paper is one of the first examinations of the question if torrefaction makes the biomass dust more explosive. Effects of torrefaction conditions on two important parameters that define the explosivity of a dust, i.e., minimum ignition temperature (MIT) and minimum explosible concentration (MEC) were studied. Above parameters were measured for Poplar wood before and after torrefaction. Three different particle size distributions of the wood, torrefied at 200, 250 and 300 °C, were tested. Exploratory experiments reported here found negligible effect of torrefaction on measured values of;Deg;ME;Deg;C and MIT of biomass. However, torrefied particles larger than 100 micron showed higher values of MIT than that for raw biomass.