Abstract
The slugging/bubbling behaviour of a wide-size range of powders has been investigated at gas pressures up to 25 bar in a 0.1 m diameter fluidised bed, by X-ray photography of slugs within the system and by direct observation of the bed surface.
It is found that in a well-fluidised bed (U−Umf > 0.05 m/s) the bubble phase is only affected when fine powders (typically <100μm) are fluidised at elevated pressure. The bubbles then become smaller, more unstable, and the two-phase theory of fluidisation increasingly invalid as the pressure is increased. For larger powders, the bubbles are the same size and just as stable at 25 bar as at 1 bar provided the bed is fluidised at the same value of (U−Umf). The two-phase theory is valid with these systems over the full range of pressure.
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© 1980 Plenum Press, New York
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King, D.F., Harrison, D. (1980). The Bubble Phase in High-Pressure Fluidised Beds. In: Grace, J.R., Matsen, J.M. (eds) Fluidization. Springer, Boston, MA. https://doi.org/10.1007/978-1-4684-1045-7_5
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DOI: https://doi.org/10.1007/978-1-4684-1045-7_5
Publisher Name: Springer, Boston, MA
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