Flow of dilute gas-particle suspensions

✍ Scribed by Martin Rhodes; Shihui Zhou; Hadj Benkreira

• Publisher: American Institute of Chemical Engineers
• Year: 1992
• Tongue: English
• Weight: 236 KB
• Volume: 38
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.690381207

✦ Synopsis

A semi-empirical model of the radial segregation of solids in upward flow of dilute gas-particle suspensions in riser systems is presented on the basis of a reduced form of the fundamental two-phase flow governing equations and experimental evidence concerning the solids concentration at the wall. The following simple expression for the radial solids concentration profile is obtained: and is in agreement with experimental data over a wide range of operating conditions: superficial gas velocity from 1.4 to 15.3 m/s, riser diameter from 0.032 to 0.40 m, imposed solids flux from 6.60 to 207 kg/m2.s, mean particle size from 32 to 120 pm and particle density from 1,000 to 3,500 kg/m3.

The model confirms the existence of the core-annulus flow structure in gas-particle suspensions reported in riser reactors, circulating fluidized beds, and the freeboard of bubbling fluidized beds.