Radial voidage variation in CFB risers

A new correlation for estimating local voidage in CFB risers is provided ba sed on data obtained in a riser of diameter 76 mm and height 6 m using FCC particles at superficial gas velocities between 4 and 8 m/s and solids circ ulation fluxes up to 425 kg/m(2).s. This equation also work, well for a wid e range of operating conditions and risers of larger size and for other par ticles. The correlation appears to have broader applicability than previous ones. It is especially useful for estimating the local voidage in the dens e zone of CFB risers and CFB risers operating under the dense suspension up flow regime where few experimental data are currently available.