Enhanced gravity closed spiral classifier: Experimental investigation

Traditional gravity classifiers that leverage differential settling velocities in the gravitational field are bulky and ineffective for particles less than 150 mu m. In this study, a newly introduced compact enhanced gravity Closed Spiral Classifier (CSC) is tested experimentally for the classification of slurries containing silica or iron ore fines. The device exploits the differential settling experienced by the particles that are carried by a fluid flowing through a closed rectangular spiral channel. The centrifugal acceleration that is much greater than acceleration due to earth's gravity enhances the particle classification. Many experiments were conducted using a 3D printed CSC to study the effects of solid system, particle loading, feed flow rate, number of turns and splitter location on the performance of the classifier. Regression models for key performance characteristics are built using the experimental observations to aid in the scale-up and design studies. The equipment is explored to a limited extent for its ability to separate desired and undesired minerals in the iron-ore fines exploiting the density differences. (c) 2022 The Society of Powder Technology Japan. Published by Elsevier BV and The Society of Powder Technology Japan. All rights reserved.

Automated summary

A newly introduced compact enhanced gravity Closed Spiral Classifier (CSC) is tested experimentally for the classification of slurries containing silica or iron ore fines. The device exploits the differential settling experienced by the particles that are carried by a fluid flowing through a closed rectangular spiral channel. The experimental observations are used to build regression models for key performance characteristics, aiding in scale-up and design studies.