Physical properties of solid biomass

The international biomass market is growing, and is expected to be a large-scale trading market in the long term future. The demand within the European Union, however, cannot be met by local supply. Therefore, a large-scale biomass bulk terminal for both solid and liquid biomass and liquid biofuels is required to accommodate the biomass flows. The capacity for the large-scale biomass bulk terminal is set at a maximum of 40 million tons per annum, with the estimated share of solid biomass of 40-50 percent. Although some of the issues or concerns (e. g. particle breakage that leads to downstream segregation problems) with regard to storage and handling of biomass can be addressed with the knowledge gained from existing dry bulk terminals, little information is available from the perspective of biomass. Therefore, experiments have been done to determine physical properties of some biomass materials. They are required to allow the design of suitable equipment (e.g. hopper) and handle biomass materials properly, i.e. the materials are handled based on first in first out stock rotation within storage vessel and/or ground storage scheme. Failure to achieve this goal will lead to the risk of negative effects and incidents such as material degradation (due to e.g. fermentation, biological reactions), selfheating (due to exothermic reaction), health hazard, and explosion. The objective of this paper is to present various decisive physical material properties of three types of solid biomass fuels: wood pellets, wood chips and torrefied pellets. The properties studied are physical material properties and the characteristics when the materials interact with the storage and handling equipment. In addition to the results, among which particle size distribution and angle of internal friction, the experimental setup as well as the relevant standards (e.g. ASTM and CEN) will be described. (C) 2011 Elsevier Ltd. All rights reserved.