Document Type

Conference Paper

Publication Date


Publication Details

Gantulga S, Tsend-Ayush Ts, Sarnai A and Altantuya B, Preliminary determination of copper recovery in the leaching process of Erdenetiin-Ovoo oxidized ore deposit, Proceedings of the 2024 Resource Operators Conference, University of Wollongong - Mining Engineering, February 2024, 350-359.


Since the Erdenet plant was put into operation, the low-grade/off-balance, oxidized and upper layer ore bodies of the open-pit mine that did not meet production requirements, defined as economically ineffective and with parameters which made the ore unsuitable to process by existing technological methods has been specially stocked and placed in the external piles of the mine according to certain classifications, creating a large accumulation of this low-grade ore. In particular, 53 million tons of oxidized ore with an average copper content of 0.5 percent, and 228 million tons of ore with a content of 0.25% which is economically efficient under certain conditions were extracted from the mine. It is obvious that the accumulated ore will be processed by Leach-Solvent Extraction/Electrowinning (L-SX/EW) hydrometallurgical technology, which is cheap, has little negative impact on the environment and widely used in copper extraction throughout the world. For several decades the oxidized ore was excavated and stockpiled separately and over the years some properties and parameters of the ore have changed significantly due to such natural factors as rainfall, wind and air temperature. Therefore, it is necessary to accurately determine the content of copper in the piles, phase distribution, minerals contained in the ore, their solubility, and then determine in detail what percentage of the total copper can be leached into sulfuric acid solution.

According to this research, considering the main parameters of the tests carried out so far on the ore from the Erdenetiin-Ovoo deposit, namely particle size P80=16-85mm, leaching time of 79-245 days, total copper content in the range of 0.10-1.19%, percentage of oxidized copper from 2.8-77.4, percentage of secondary copper from 1.4 to 89.4, total iron content in the range of 0.6-5.7% and taking into account the copper recovery in the range of 6.2-80.3% we developed a mathematical model for predicting copper recovery by processing the results of numerous column leaching experiments.