Experimental hydrocyclone coping models

Hydrocyclone roping has not been studied and modeled in true grinding circuits. The paper discusses experiments made with a pilot size closed grinding circuit treating 0.5-1.0 t/h crystalline limestone. The equations found in the literature did not all describe roping very well. The best results were obtained by predicting the underflow solids volume flow. Equations based on underflow particle size did not give good results. Roping had mixed effects on the performance of the grinding circuit depending upon how it was obtained. Experiments were made by initiating roping through increasing mill feed rate or decreasing cyclone apex diameter. Varying responses are discussed in the paper. The estimation given in literature, that a circuit has the optimal operational point close to roping, was also confirmed for this set-up. (C) 2000 Elsevier Science B.V. All rights reserved.