Interphase mass transfer coefficient in fluidized bed combustion by Eulerian CFD modeling

• Interphase mass transfer coefficients rise exponentially with particle size.
• Kbe increases exponentially with the fluidization velocity.
• kbe is independent on fluidization velocity, except for Geldart D solids.
• In fine particle beds, interphase mass transfer is controlling reaction rates.

Eulerian gas–solid CFD simulations are applied to derive interphase mass transfer coefficients for the Geldart B and D solids in a bench and a pilot size fluidized bed combustion reactor. The interphase mass transfer coefficients obtained from the bubbling and turbulent churning fluidized bed CFD simulations are compared to the empirical data and correlations, which are primarily available only for the Geldart A solids. Particularly, the effect of fluidization velocity, particle diameter and bubble size on the interphase mass transfer coefficients is evaluated.