Liquid-solid fluidized beds are used in mineral processing industries to separate particles based on particle size,density,and shape.Understanding the expanded fluidized bed is vital for accurately assessing its performance.Expansion characteristics of the fluidized bed were studied by performing several experiments with iron ore,chromite,quartz,and coal samples.Using water as liquid medium,experiments were conducted to study the effects of particle size,particle density,and superficial velocity on fluidized bed expansion.The experimental data were utilized to develop an empirical mathematical model based on dimensional analysis to estimate the expansion ratio of the fluidized bed in terms of particle characteristics,operating and design parameters.The predicted expansion ratio obtained from the mathematical model is in good agreement with the experimental data. Liquid-solid fluidized beds are used in mineral processing industries to separate particles based on particle size, density, and shape. Understanding the expanded fluidized bed is vital for immediate assessing its performance. Expansion characteristics of the fluidized bed were studied by performing several experiments with iron ore, chromite, quartz, and coal samples. Using water as liquid medium, experiments were conducted to study the effects of particle size, particle density, and superficial velocity on fluidized bed expansion. experimental data were utilized to develop an empirical mathematical model based on dimensional analysis to estimate the expansion ratio of the fluidized bed in terms of particle characteristics, operating and design parameters. The predicted expansion ratio obtained from the mathematical model is in good agreement with the experimental data.