Laboratory tests and methodology for the design of centrifugal filtration-washing-dewatering cycles

• Published in: Filtration & separation Vol. 29; no. 3; pp. 254,238 - 260,238
• Main Authors: Fournet, F., Klein, J.P., Baluais, G., Remy, J.F., Dodds, J.A., Leclerc, D.
• Format: Magazine Article
• Language: English
• Published: Oxford Elsevier B.V 1992; Elsevier
• Subjects: Applied sciences; Centrifugation, cyclones; Chemical engineering; Exact sciences and technology; Liquid-liquid and fluid-solid mechanical separations; Centrifugal filter; Filtration; Centrifuging; Theoretical study; Laboratory scale; Lixiviation; Particle suspension; Dehydration; Experimental study; Mathematical model; Liquid solid
• ISSN: 0015-1882; 1873-7218
• DOI: 10.1016/0015-1882(92)80256-I

Pilot plant tests of industrial batch centrifuges are costly, difficult to carry out and often pose problems in data analysis. Conventional laboratory filtration tests do not replicate industrial centrifuge cycles and in particular neglect the effects of centrifugal force on cake structure. In this work the performance of a batch centrifuge is compared with predictions based on standard laboratory tests and previously published models of cake structure and fluid flow. Experiments were performed on a 500 mm diameter pilot centrifuge fitted with either its standard basket, or a cylindrical filter cell. A program has been developed to optimise process design based on: (1) Values of specific cake resistance, compressibility, and porosity, measured by standard constant pressure filter tests; (2) Calculated pressure profiles. This methodology is applied to the centrifugal filtration and dewatering of both model and non-ideal suspensions. Predictions of the filtration phase are correct to within 15% and the dewatering phase to better than 20%.