Hydrodynamics of fluidized bed flotation column: Experimental and statistical analysis--颗粒学报PARTICUOLOGY

a State Key Laboratory of Coking Coal Resources Green Exploitation, China University of Mining and Technology, Xuzhou, 221116, China
b Chinese National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou, 221116, China
c School of Chemical Engineering & Technology, China University of Mining and Technology, Xuzhou, 221116, China

10.1016/j.partic.2025.03.005

Volume 100, May 2025, Pages 14-26

Received 10 December 2024, Revised 5 March 2025, Accepted 6 March 2025, Available online 15 March 2025, Version of Record 20 March 2025.

E-mail: cumtxyw@126.com; guixiahui1985@163.com

Highlights

• Operating conditions effects on hydrodynamics in fluidized bed were investigated.

• Electrical resistance tomography was used to identify flow regimes.

• Radial gas-solid holdup distribution in different flow regimes were detected.

• BBD and ANOVA were used to identify the variables interaction effects.

Abstract

The hydrodynamic characteristics in fluidized bed flotation column (FBFC) are critical for optimizing fluidized flotation processes, yet understanding the interactions between operating parameters remains a complex challenge. This study proposes a novel method to classify flow regimes and identify transition velocities in fluidized bed flotation columns. By analyzing gas-solid holdup variations (ε_g,s) via electrical resistance tomography (ERT), we identified three distinct flow regimes and two transition velocities using ε_g,s-based criteria. Furthermore, we employed pressure transducer and ERT to analyze how gas velocity (U_g), water velocity (U_w), and particle size (D_p) influence pressure fluctuations, minimum liquid fluidization velocity (U_mf), and gas and solid hold-ups distributions. Results showed that U_w and D_p significantly influenced pressure fluctuations, while U_g affected pressure fluctuations mainly for large particles. U_mf increased with D_p but remained unaffected by U_g. Higher U_w and D_p led to more uniform distributions of radial gas and solid hold-ups, with U_g influencing distribution only in the fixed bed regime. Finally, the using Box-Behnken design (BBD) and analysis of variance (ANOVA), significant interactions between U_g and D_p for the average differential pressure, and between U_w and D_p for ε_g,s were identified, with no significant interactions for normalized standard deviation of differential pressure fluctuation. Predictive models with high correlation coefficients were established for these interactions, offering guidance for FBFC optimization.

Graphical abstract

Keywords

Fluidized bed flotation column; Hydrodynamics; Electrical resistance tomography; Pressure transducer; Phase hold-up; Variance analysis

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