A behaviour of a catalyst powder flowing down in a dipleg

The dipleg can generally operate in three basic flow regimes; packed-bed, f luidized-bed flow and a dilute flow called streaming flow. The most common perception of an overflow dipleg is that it consists of a fluidized dense p hase at the bottom and a dilute phase in the upper part. This paper present s the tomographic images obtained at three locations along the dipleg. Thes e show the effects of solids mass fluxes and the backpressure on the charac ter of solids distribution along the pipe cross-section. The radial profile s of average solids distribution are compared with the literature data. (C) 2000 Elsevier Science S.A. All rights reserved.