Modernizized technological scheme for ore processing of the Udokan deposit

This study aims to develop engineering solutions that would facilitate the elimination of the extraction stage from the processing of Udokan ore (Russia), while ensuring complete recovery of the target element into copper cathode. The efficiency of incorporating two cleaning stages into the flotation cycle was evaluated using a sample of oxidized copper ore with an initial copper content of 1.1%. The flotation was carried out using FMP-L1 and FMP-L3 flotation units. To develop the proposed metallurgical process, we obtained a sulfide concentrate with a copper content of 12.2% from sulfide ore containing 2.5% copper. The concentrate was roasted in a tubular rotary furnace. The sulfuric acid leaching of the roasted product was carried out using bubbling with air at a liquid-to-solid ratio (L/S) of 5:1, an acid concentration of 3 g/L, and a temperature of 60–70°C. The phase and elemental compositions of the solid products were determined using a combined X-ray diffraction and X-ray spectroscopy method. The proposed process solutions include: (1) production of a bulk concentrate with a copper content exceeding 15% through two additional cleaning stages during bulk flotation; (2) sulphatising roasting of the resulting concentrate; (3) sulfuric acid leaching of the roasted product under intensive bubbling with air or oxygen-enriched air, followed by iron precipitation, pulp filtration, and solution electrolysis to produce copper cathodes. It was established that the introduction of a preliminary sulfatizing roasting stage prior to the hydrometallurgical cycle results in 95–97% copper extraction into solution under atmospheric leaching conditions. Furthermore, this approach reduces sulfuric acid consumption in side reactions and eliminates the need for sulfide flotation and extraction/re-extraction stages. copper cathode and anode slime for subsequent refining. The exclusion of the extraction cycle from the Udokan ore processing scheme simplifies the process, improves flotation performance and reduces reagent consumption, thereby resulting in a significant decrease in production costs for both flotation concentrate and copper cathode.

mixed copper ore processing, Udokan deposit, flotation, oxidizing roasting, sulfating roasting of bulk concentrate, atmospheric leaching