The technology of copper enrichment from the ore of the Udokan deposit with the possibility of extracting precious metals

In 2023, Udokan Copper LLC completed the construction of the first stage of the Mining and Metallurgical Combine (MMC) and intends to build the second stage. The planned annual productivity is 40 million tons of processed ore and 400 thousand tons of cathode copper. In the conditions of a difficult economic and geopolitical situation, the company faces the goal of constructing the second stage of the MMC with a high share of domestic technologies and equipment. This article describes technologies for the enrichment of copper from the ore of the Udokan deposit with the use of roller presses instead of semi-self-grinding mills used at the first stage of the MMC, and atmospheric leaching of copper with subsequent extraction/reextraction and electrolysis. The possibility of obtaining silver from leaching cake by cyanidation with subsequent sorption/adsorption is described. Eventually, the company will be able to produce sulfide concentrate, cathode copper that meets the requirements of the London Stock Exchange (LME) in chemical composition, and silver. This production can be carried out with the use of up to 85 % of domestic equipment at the ore preparation and flotation workshops and up to 80 % at the hydrometallurgical workshop. Flotation reagents capable of fully replacing foreign analogues are proposed. The presented technologies will increase the extraction of copper from ore by 1.2-1.5 %. Options for processing enrichment tailings and the possibility of recycling basic resources (water, acids) were also considered. Taking into account the specifics of the MMC's location, the issue of tailings disposal remains open. A variant of creating a temporary tailings storage facility with the possibility of partial loading of tailings into wagons for shipment to enterprises specializing in the production of building materials is proposed.