Spouting behavior of binary particle mixtures of different densities: Fluid dynamics and particle segregation--颗粒学报PARTICUOLOGY

Santos, K. G., Santana, R. C., Souza, D. L., Murata, V. V., & Barrozo, M. A. S. (2019). Spouting behavior of binary particle mixtures of different densities: Fluid dynamics and particle segregation. Particuology, 42, 58-66. https://doi.org/10.1016/j.partic.2018.02.005

Spouting behavior of binary particle mixtures of different densities: Fluid dynamics and particle segregation

K.G. Santos ^a *, R.C. Santana ^b, D.L. Souza ^a, V.V. Murata ^b, M.A.S. Barrozo ^b

a Federal University of Triangulo Mineiro, Chemical Engineering Department, Univerdecidade Campus, Uberaba, MG, Brazil
b Federal University of Uberlandia, Chemical Engineering School, Uberlandia, MG, Brazil

10.1016/j.partic.2018.02.005

Volume 42, February 2019, Pages 58-66

Received 29 November 2017, Revised 7 February 2018, Accepted 9 February 2018, Available online 3 September 2018, Version of Record 21 January 2019.

E-mail: kassia.santos@uftm.edu.br

Highlights

• Fluid dynamics and segregation in spouted bed of binary mixture differing in density were studied.

• Complete minimum spouting condition was characterized for the binary particle system.

• Effects of mixture composition and static bed height on particle segregation were investigated.

• Particle segregation was strongly affected by the mixture composition.

Abstract

Numerous industrial applications of spouted beds involve a mixture of granular particles, where differences in particle size, density, and shape can cause particle segregation, affecting the quality of flow and decreasing product homogeneity. The aim of this study was to investigate the particle segregation and fluid dynamics of a conical spouted bed operating with a binary mixture of particles of different densities. Using glass beads and polyethylene particles with a diameter of 4 mm, we determined the effects of the mass fraction of denser particles and static bed height on the minimum spouting condition and mixture index. The pressure drop and airflow in the minimum spouting condition increased with an increase in bed height or jetsam concentration. Regarding particle segregation, the jetsam particles tended to concentrate near the bottom, at the spout–annulus interface because they have a shorter trajectory than the lighter particles in the fountain region. Jetsam-rich mixtures with high initial static bed heights exhibited more efficient particle mixing, excluding those at the bottom of the bed.

Graphical abstract

Keywords

Density; Segregation; Spouted bed; Binary mixtures

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