화학공학소재연구정보센터
Powder Technology, Vol.195, No.2, 73-82, 2009
Percolation segregation of binary mixtures under periodic movement
Three strain rates of 1.0, 0.5, and 0,25 Hz were selected for studying percolation segregation in binary mixtures of urea (spherical) and potash (angular). Mixed binary samples prepared from three mean coarse sizes with their corresponding three and two fines sizes for potash and urea, respectively. Herein, three coarse mean sizes 3675, 3075, and 2580 pm and three mean fine sizes 2180,1850, and 1550 pin were selected for tests. Percolation segregation in mixed binary sample was quantified using the primary segregation shear cell (PSSC-II). Based on experimental results, the segregated fines mass, normalized segregation rate (NSR) and segregation rate of fines for binary mixtures increased with increasing strain rate from 0.25 Hz to 1.0 Hz. The NSR decreased with decreasing strain rate from 1.0 Hz>0.5 Hz>0.25 Hz for size ratios 1.7, 2.0, and 2.4 (p<0.05). At these three strain rates, for size ratio 2.0, the NSR of coarse size 3675 mu m with fines size 1850 mu m was smaller than the NSR of coarse size 3075 pm with fine size 1550 mu m in the binary mixtures (p<0.05). At three strain rates of 1.0, 0.5, and 0.25 Hz, the NSR for potash was higher (53%, 56%. and 46%) than the NSR for urea for the same size ratio (p<0.05). Published by Elsevier B.V.