Experimental validation of a fluid dynamics based model of the UF Falcon concentrator in the ultrafine range
Abstract
The process of separating ultrafine particles, say below 80 μm, on the basis of density is a true technical challenge. Indeed, the separation process itself becomes very much size dependent with such fine particles, so that large enough density differentials are necessary for offsetting the strong particle size effect. Our study is concerned with understanding the limitations of the UF Falcon concentrator, an enhanced gravity separator specifically designed for treating slurries with ultrafines. To this end, based on a number of hypotheses, we have already derived and published a theoretical model of the UF Falcon concentrator for treating dilute suspensions. This paper presents the validation and calibration of this model, based on experimental measurements carried out under controlled conditions using a laboratory scale concentrator. By comparing measured and predicted separation results for particles with known size distribution and density, the work validates the key model hypotheses, thereby confirming our understanding of the physics of the separation process. Moreover, by changing operating conditions in a systematic manner, the work is able to calibrate the model so that it can be used to make quantitative prediction of the UF Falcons performance.