TY - JOUR

T1 - A reanalysis of fragmentation data from the Red Dog mine – Part 2

AU - Ouchterlony, Finn

AU - Paley, Norman

PY - 2013

Y1 - 2013

N2 - Detailed fragmentation data for different blast delay timing tests at the Red Dog mine in Alaska are analyzed. This work is a continuation of previous work in which the crusher output was found to be better described by the three-parameter Swebrec function than by the Rosin-Rammler function. For a crusher model, the x50 variable sufficed to describe changing crusher input while b and xmax could be considered fixed. For the crusher output from aggregated stockpile rock, as measured by digital image analysis using Split-Online, the constancy of b was not as apparent. In this paper detailed stockpile data, single Split data series, and sieved belt cuts of crusher product are analyzed using the Swebrec and truncated Rosin-Rammler functions. The variability of b is confirmed. By using specific fraction passing sizes a shortcut is presented that removes the need to do curve fitting to determine the three Swebrec function parameters. Prediction equations are presented for these parameters for the tests involving the effect of inter-hole delay time on crusher output. The slope value at x50 was found to be independent of timing, unrelated to the estimated milling properties, and well approximated by 0,5/(x75-x25).

AB - Detailed fragmentation data for different blast delay timing tests at the Red Dog mine in Alaska are analyzed. This work is a continuation of previous work in which the crusher output was found to be better described by the three-parameter Swebrec function than by the Rosin-Rammler function. For a crusher model, the x50 variable sufficed to describe changing crusher input while b and xmax could be considered fixed. For the crusher output from aggregated stockpile rock, as measured by digital image analysis using Split-Online, the constancy of b was not as apparent. In this paper detailed stockpile data, single Split data series, and sieved belt cuts of crusher product are analyzed using the Swebrec and truncated Rosin-Rammler functions. The variability of b is confirmed. By using specific fraction passing sizes a shortcut is presented that removes the need to do curve fitting to determine the three Swebrec function parameters. Prediction equations are presented for these parameters for the tests involving the effect of inter-hole delay time on crusher output. The slope value at x50 was found to be independent of timing, unrelated to the estimated milling properties, and well approximated by 0,5/(x75-x25).

M3 - Article

VL - 7

SP - 139

EP - 172

JO - Blasting and Fragmentation

JF - Blasting and Fragmentation

SN - 1937-6359

IS - 3

ER -