Investigation on pre-weakening and crushing of phosphate ore using high voltage electric pulses

Mechanical size reduction processes in the mineral processing industry are energy intensive. In this study, a novel High Voltage Electric Pulses Crusher (HVEPC) was designed and developed to pre-weaken and crush a phosphate ore. To compare the effectiveness of the new HVEPC in crushing with the conventional crushers, several rock samples of a phosphate ore were used and the effect of the capacitor, the voltage level and voltage rise time on the phosphate ore breakage was investigated. Comparing the particle size distribution of the crushed samples using both the HVEPC and the conventional crushers revealed the difference between their breakage mechanisms. The final results showed that applying the high voltage pulses at specific energy of 3-5 kWh/t could significantly increase and extend the cracks and microcrakcs inside the rocks and consequently lead to decline in the Bond crushability and Abrasion indices of the crushed samples by 10.6% and 28.1%, respectively. (C) 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.