Physical and flow properties of fly ash from biomass combustion

This chapter presents a characterization of different fly ashes from grate-fired biomass combustion (cyclone fly ash, electrostatic precipitator fly ash and fabric filter fly ash) with respect to storage and flow relevant properties. Physical property measurements, including particle size distribution, bulk density, tapped bulk density and particle density, are presented. Powder flowability was measured using a ring shear tester. The flowability of the different fly ashes is compared and discussed with reference to their physical properties. The wall friction angles with different wall materials were measured using a ring shear tester for wall friction tests. Angles of repose were also determined. The application of powder flowability data is important in, for example, the design of hoppers of fly ash collection equipment or fly ash storage silos.