METHOD OF HEAP LEACHING OF METALS FROM DIFFICULTY PERMEABLE HIGHLY ARGILLACEOUS ROCKS Russian patent published in 2002 - IPC

FIELD: mining. SUBSTANCE: method includes formation of impervious base, rock pile to be leached and supply of reagent leaching solutions for dissolving of metals from mined bulk. First, located near impervious base, on area exceeding base area, is flat rock heap not above 2.5 m high. During cold season, as its surface becomes frozen to depth of 0.1-0.15 m, frozen crust is periodically crushed and moved to impervious base, where new pile is formed from lumps of frozen rock. Metal leaching is started after completion of pile formation by supply of reagents of high concentration and temperature to heap. EFFECT: increased filtration coefficient of leached rocks and intensity of leaching process.