This article displays a thickness comparison between an industrial scale campaign test and some bench scale tests for sedimentation and proposes correction factors for the classical dimensioning methods for the conventional thickeners. Brazilian iron ore processing has consolidated a substancial modification of the classical Kynch's method (under the Talmage & Fitch's graphical procedure). It involves the adoption of the mass concentration value corresponding to the height of the slurry/supernatant interface after 24 hours of rest in a conventional graduated cylinder test, instead of that corresponding to the nominal underflow concentration in the industrial thickener. The tests indicate that the calculations for the solid-loading area need to be corrected by a multiplicative factor of 0.64 for slime thickeners and 1.3 for pellet feed thickeners.
Thickening; sizing; settling
