Experimental characterization of the size, shape and ash composition of solid particles from different biomasses and separated by elutriation

Abstract

Biomass particles have a wide variety of size and shape, and their characterization is fundamental for energy generation design, production of biofuels, simulation, and sizing of processes involving two-phase flow, such as fluidized bed, fixed bed, and aerodynamic transport. In order to find design data for projects involving biomass, this study characterized sugarcane bagasse, sugarcane straw, bamboo, and cassava plant branches regarding size and shape, using two methods of particle separation: sieving and elutriation, in addition to image analysis. An experimental bench was built for the separation of biomass by elutriation. Each biomass was separated by sieving in the range 388 to 2360μm openings and drag velocities from 0.6 to 6 m/s. The size distribution (mass, major and minor axis length, area and volume) and the calculation of sphericity resulted in different patterns according to the method used: sieving or elutriation. Biomass portions of smaller physical size, or smaller aerodynamic size, concentrate a higher ash content than larger portions. However, some minerals, such as Fe, Si, and Cl, were more concentrated in larger particles, characteristic details that may be useful for controlling the composition of biomass ash to prevent corrosion or incrustation in thermal process equipment.