Prediction of the minimum fluidization velocity of particles of sugarcane bagasse

Abstract

A B S T R A C TThis study refers to an experimental analysis of the fluid-dynamics of particles of sugarcane bagasse in a fluidization column with an internal diameter of 190 mm, which determined the minimum fluidization velocity of the particles with different characteristic diameters (0 < dp < 9.5 mm), using air as fluidization means. The results have shown that the minimum fluidization velocity has a tendency to increase as the diameter of the particle increases. However, in a certain range of diameter (0.88 mm < dp < 9.5 mm), where the particles have a high aspect ratio (length/diameter), it has not been possible to fluidize them. High superficial air velocities have been used, mainly due to the strong trend to interlace and to develop high adhesion forces in this type of particles, as well as the high porosity that is displayed. Based on the experimental results, two new models have been developed in order to determine the minimum fluidization velocity and the complete fluidization velocity of the sugarcane bagasse with diameters that range from 0.075 to 0.445 mm. The comparisons have been made by using correlations from the literature for the determination of the minimum fluidization velocity, and the experimental results have shown that the new suggested correlations finely predict this parameter, with a maximum error range of 6%, respecting the experimental values.

Fluidization of binary mixtures of biomass and coal with sand: an experimental study

“…Tannous and Lorenço [10] reported that their correlation for determining apparent fluidization velocity was valid for Reynolds number values between 1.4 and 14, as observed in Eq. (9). Mixtures of pinus bark and sand and eucalyptus bark and sand of this experiment were outside the range established by the authors but are nevertheless shown in Table 7.…”

“…Biomass characteristics such as density, size and sphericity directly affect the fluidization. Pérez et al [9] carried out a study on the fluid dynamics of a scale fluidized bed with 190 mm of internal diameter and 2500 mm in height, using air as a fluid phase and sugarcane bagasse as biomass. The authors investigated the effects of particle diameter, density and shape on the fluid dynamics behavior and compared the experimental results of the minimum fluidization velocity with different correlations presented in the literature.…”

Hydrodynamics Behavior of Ternary Biomass Mixtures with Silica Sand in Fluidized Beds: Experiment and Artificial Neural Network Model Development

“…12,56 As shown in Figure 3, it was possible to determine the complete fluidization point from the pressure drop versus superficial gas velocity profiles by identifying the intersection between the rising pressure drop line and the flattened pressure drop line. 12,56 It is clear that silica sand fluidized at relatively lower superficial velocities and had the least pressure drop ΔP/H, which could be attributed to these particles being smaller in diameters and having high sphericity. 4 Due to interparticle cohesive forces, the pressure drop first increased with superficial gas velocity, and then after the minimum fluidization point, it dropped sharply before becoming constant (i.e., it did not change on any further increase in the superficial gas velocity).…”

Mixing Characteristics of Binary Mixture with Biomass in a Gas-Solid Rectangular Fluidized Bed

“…Accurate knowledge of the minimum fluidization velocity is fundamental in understanding the hydrodynamic behavior of binary systems in the fluidized bed [15]. The general method of pressure drop vs. superficial gas velocity is employed to determine the minimum fluidization velocity in this section.…”