Modeling heat and mass exchange processes in ore pile in heap leaching under low ambient temperature

The article presents the computational algorithm developed for modeling metal leaching process in cross section of gold ore pile. The model allows predicting processes of heat and mass convection in the pile body and includes equations of convective heat transfer with regard to possible phase transitions of leaching solution and the solution temperature changes during feeding, as well as equations of convective diffusion of leaching solution and dissolved metal. A separate stage is an approximate solution for diffusion of the same components in lump ore. Overall contributions of diffusion flows from all lump ore in the reaction zone are used as sources and sinks in the related equations of convective diffusion. The model input data are physicochemical, geometrical and operational parameters such as: content of ore to be leached, cyanide concentration and feed rate, size distribution of lump ore and cross dimension of pile. The model enables prediction of both metal recovery and reagent consumption using available input parameters. Modeling can provide justified data for both pre-feasibility study and optimization of operation conditions.

Kurilko A. S., Popov V. I. Modeling heat and mass exchange processes in ore pile in heap leaching under low ambient temperature. MIAB. Mining Inf. Anal. Bull. 2021;(1):111-119. [In Russ]. DOI: 10.25018/0236-1493-2021-1-0-111-119.

A.S. Kurilko¹, Dr. Sci. (Eng.), Chief Researcher,
V.I. Popov₁, Cand. Sci. (Eng.), Senior Researcher, e-mail: popov.gtf@mail.ru,
¹ Chersky Mining Institute of the North, Siberian Branch, Russian Academy of Sciences, 677000, Yakutsk, Republic of Sakha (Yakutia), Russia

V.I. Popov, e-mail: popov.gtf@mail.ru.

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