Electronic Thesis and Dissertation Repository


Master of Engineering Science


Chemical and Biochemical Engineering


Jesse Zhu

2nd Supervisor

Shahzad Barghi



Gas-solid fluidized beds are widely used in industrial dry coal preparation to separate waste from coal (still a primarily important energy source worldwide). It is the density difference between coal and the waste that enables the separation. Experiments were carried out in a two dimensional gas-solid fluidized bed. Filtered air at room temperature was used as the fluidizing gas, while magnetite, sand (two types) and FCC catalyst particles belonging to Geldart groups A and B were used as bed particles. Image processing and Matlab were applied for bubble size and velocity measurements. Bubble properties and bed expansion in fluidized beds of four single-component particles and binary systems were studied. Bubble size and bubble rise velocity were found to be proportional to the distance above the gas distributor and excess gas velocity. Bubble diameter is reduced by the addition of lighter and smaller particles in a binary system. In addition, a new empirical correlation for estimation of bubble diameter was proposed for single-component and binary fluidization systems. The results were in good agreement with the experimental data.


Coal beneficiation, two-dimensional gas-solid fluidized bed, image processing, bubble size, bubble velocity, bed expansion