Effect of HPGR comminution scheme on particle properties and heap leaching of gold

© 2020, © 2020 Canadian Institute of Mining, Metallurgy and Petroleum. The effect of high-pressure grinding roll (HPGR) comminution on the physical properties of ore particles and heap leaching of gold was investigated compared with that of conventional jaw crusher comminution. The comminuted products were evaluated in terms of particle size distribution, internal crack density, and saturated water content. Compared to conventional jaw crushers, the HPGR produced finer particles with more internal cracks. Moreover, the HPGR particles contained a higher water content in the ore heap. Under optimum conditions, the HPGR comminution scheme was found to significantly enhance the leach recovery of gold, in addition to reducing cyanide consumption. However, the fine particles generated during mini-column leaching, reduced the permeation velocity drastically for HPGR products