TESTING OF REFRACTORY GOLD-COPPER ORES BY THE METHOD OF ACTIVATED PERCOLATION LEACHING

Abstract

One of the largest and most attractive mining projects in the Russian Far East is Malmyzh porphyry copper deposit. Despite the low content of valuable components, the reserves of copper and gold in this deposit are huge. The balance reserves of the Malmyzh deposit are estimated at 5.156 million tons of copper and 278 tons of gold. Testing of primary ores of one of the areas of the Malmyzh deposit revealed their technological refractory and the need to develop new technological approaches for solving the problem of extracting copper and gold from porphyry goldcopper ores. The possibility of extracting valuable
components by leaching by percolation has been studied. This technology is implemented in industry as heap leaching and is characterized by high labor productivity, low capital and operating costs, which is especially important for porphyry copper ores with a low copper content. Testing of refractory gold-copper ores using electro-and-photo-activated non-cyanic leaching solutions revealed the fundamental possibility of using percolation leaching for refractory goldcopper-porphyry ores. Electro and-photo-activation of leaching solutions was carried out sequentially by electrolysis followed by irradiation with an ultraviolet
emitter in order to form reactive oxygen species in the solution volume, which are strong oxidizing agents. When testing the diorite-porphyritic type of ore, a nitric acid-chloride-sulfuric acid scheme with nitrogen-nitrite pre-oxidation was used. A feature of this scheme is the use of a pregnant solution containing iron oxide ions as a reverse one at the pre-oxidation stage.