One way of representing the size and shape of biomass particles in combustion modeling

This study aims to provide a geometrical description of biomass particles that can be used in combustion models. The particle size of wood and herbaceous biomass was compared using light microscope, 2D dynamic imaging, laser diffraction, sieve analysis and focused beam reflectance measurement. The results from light microscope and 2D dynamic imaging analysis were compared and it showed that the data on particle width, measured by these two techniques, were identical. Indeed, 2D dynamic imaging was found to be the most convenient particle characterization method, providing information on both the shape and the external surface area. Importantly, a way to quantify all three dimensions of biomass particles has been established. It was recommended to represent a biomass particle in combustion models as an infinite cylinder with the volume-to-surface ratio (V/A) measured using 2D dynamic imaging.The authors would like to acknowledge the financial support received from the Danish Strategic Research Council (Grant Nr. DSF-10-093956), Kempestiftelse, DONG Energy, Vattenfall and HOFOR. We would like also to thank Ian Haley and Brian O’Sullivan from Mettler Toledo for assisting with FBRM measurements. The authors thank DTU Combustion and Harmful Emission Control group for the fruitful discussions. Erika Christ is acknowledged for the article proof reading.peer-reviewed2019-06-2