Advances in high-temperature heap leaching of refractory copper
In the case of sulfide leaching, the heat generation could increase the heap surface temperature [11][12] [13], increasing the temperature gradient difference between solid and liquid phases on ...
(PDF) Copper heap leaching: Process, principles and …
2019, Petersen, J and van Staden, P. Chapter 3. Heap leaching: Pr ocess, principles and practical considerations. pp. 52-78 in: Copper Hydrometallurgy: Principles and Practice. Berend Wassink and ...
Agglomeration of fine-sized copper ore in heap leaching …
Heap leaching is a low-cost, flexible hydrometallurgical process for recovering valuable metals from low-grade ores (Nosrati et al., 2012). ... Subsequently, the agglomerates were first cured at 30 °C for 12 h and then cured at room temperature for 36 h. Table 2 presents the preparation conditions of the agglomerates, in which the variable …
Heap leaching of poor nickel laterites by sulphuric …
Chapter. pp 193–208. Cite this chapter. Download book PDF. S. Agatzini-Leonardou & D. Dimaki. 842 Accesses. 12 Citations. Abstract. Column leach tests were conducted to …
The Effect of Aeration on Chalcocite Heap Leaching
The Effect of Aeration on Copper Leaching Kinetics. Figure 2 shows the copper concentration in the PLS and the cumulative extraction with and without aeration. Despite the lower cyanide soluble copper grade and larger particle size in the heap with aeration, which are unfavorable conditions for leaching, the aerated heap yielded PLS …
Temperature control in copper heap bioleaching
Introduction. Temperature is among the key factors that control the kinetics of copper leaching from different copper-bearing sulfide minerals, such as chalcocite and chalcopyrite. Extraction of copper from chalcocite using bacterially-assisted heap leaching has been successfully practiced on a commercial scale (Petersen, 2016).
Progress in bioleaching: part B: applications of microbial
The Zijinshan heap bioleach plant demonstrates that high concentrations of ferric ion, low pH values, and elevated temperature facilitate copper leaching even with apparent low bacteria activity. A copper recovery of 80 % is reported at the Zijinshan plant (Ruan et al. 2011).
Copper Heap Leaching | Encyclopedia MDPI
Heap leaching is a firm extractive metallurgical technology facilitating the economical processing of different kinds of low-grade ores that are otherwise not exploited. hydrometallurgy leaching gangues clays minerals heap leaching agglomeration. 1. Introduction. According to Toro et al. [ 1], copper mining is an industry that is in constant ...
(PDF) Heap leaching as a key technology for …
High temperature heap leaching of chalcopyrite: method of evaluation and process model validation. In International Conference: Percolation l ea ching : The status globally and
BIOHEAPLEACHING IN BOREAL CONDITIONS
This phenomena leads to an idea of temperature indicating leaching process state opening a possibility to follow up the leaching process more detailed. 5. Heap structure A leaching heap is constructed in a field with bottom ground angle of ca. 3 degrees. One heap consists of three sections each of 350 meters wide and 400 m in length. Drainage
(PDF) Heap Leaching: Practice and Fundamentals
PDF | The theory and practice of copper and gold heap leaching | Find, read and cite all the research you need on ResearchGate
Heap Leaching
The leaching reactions are exothermic, so the heap will increase marginally in temperature as the leach liquor percolates through the heap. This further accelerates the rate of leaching; however, significant heat is lost via evaporation from wetted surfaces …
Heap Leaching in Cold Weather & Winter
Loss of leaching availability can be serious, cutting total available leaching time to as little as 8 months per year in many cases. To increase leaching time and precious metal production, several methods have been developed and others can be considered. Some feel that heating of solutions might provide protection against glazing …
Modeling the hydrodynamics of heap leaching in sub-zero …
In the 'test' heap the hydraulic conductivity is assumed to vary by depth which is typical for large heaps. The 'test' heap is leached over a one-year period assuming (1) above zero temperature fluctuations, (2) Seasonal temperature variation with above-, near- and sub-zero temperatures.
Heap leaching
In 2011 leaching, both heap leaching and in-situ leaching, produced 3.4 million metric tons of copper, 22 percent of world production. The largest copper heap leach operations are in Chile, Peru, and the southwestern United States. Although heap leaching is a low cost-process, it normally has recovery rates of 60-70%.
Heap Leaching
Heap leaching had become a fairly sophisticated practice at least 500 years ago. Georgius Agricola, in his book De Re Metallica (publ. 1557) ... Although the rate of dissolution increases with increases in temperature, it is difficult to control temperature in a large heap. Actual temperature measurements within the heaps usually indicate a ...
Gangues and Clays Minerals as Rate-Limiting Factors in Copper Heap
Heap leaching is a firm extractive metallurgical technology facilitating the economical processing of different kinds of low-grade ores that are otherwise not exploited. Nevertheless, regardless of much development since it was first used, the process advantages are restricted by low recoveries and long extraction times. It is becoming …
Towards fundamentally based heap leaching scale-up
Design engineers have resorted to experience-based extrapolation from column-leaching data. Examples are Jansen and Taylor, (2002) (who advocate that the time for a given extraction in a column be multiplied by 1.25 to 1.50 and the final column extraction be multiplied by 0.95 to predict the heap performance); John, (2011) (who …
Current scenario of chalcopyrite bioleaching: A review on …
In contrast, heap leaching operations carried out under harsh environmental conditions such as extreme temperature might experience failures due to damage of geomembrane liner systems with the base temperature of heap leach pad exceeding 50 °C (Guyonnet and Touze-Foltz, 2014 and references therein; Lupo, 2010). It therefore …
Modeling the hydrodynamics of heap leaching in sub-zero …
The 'test' heap is. Conclusions. For real-world leaching predictions, full scale heap simulations must account for changing meteorological conditions and diverse climates. Temperature variations, evaporation, rainfall, freezing and thawing can significantly affect the hydrodynamics of the heap and influence recovery.
Thermophilic heap leaching of a chalcopyrite concentrate
Thermophiles have been shown to be the only micro-organisms to leach chalcopyrite successfully. Heap leaching may be a feasible alternative to conventional bio-reactors, providing a high temperature environment can be maintained within the heap without external heating.. In the present study thermophilic heap leaching of a …
Recent Progress in Hydrometallurgical Processing of Nickel …
3.3 Heap Leaching. HL is an industrial process, and ore is left for steady-state operation at ambient temperature. The process has low recovery, with ~ 68–71% nickel extraction. The heap leach operation prefers a low ratio of limonite to saprolite ore . Two commercial operations were reported for HL in the literature : a.
Principles, Mechanisms And Dynamics Of Chalcocite Heap Bioleaching
INTRODUCTION. Heap leaching is a well established mini ng technology that involves stacking. crushed ore into piles constructed on an impermeable layer fitted with a. solution drainage system, or ...
Bioleaching Modeling—A Review
The heap leaching technology was pioneered in the U.S.A., but significant advancements were made to it in Chile, ... bioleaching is started by adding sulfuric acid and aerating the heap, the temperature of which rises as leaching progresses. The first organisms to act are mesophilic acidophiles (temperature < 40 °C), ...
Heap Leaching
Apr 23 2014. Heap leaching is an industrial mining process of separating precious metals, copper, and other minerals, from ores. It involves a series of chemical processes, …
A Review on the Research of Hydrometallurgical …
Research by Peterson et al. showed that the temperature of thermophilic heap leaching of a chalcopyrite concentrate could increase to 70 °C while successively …
A Review on the Research of Hydrometallurgical Leaching of …
Research by Peterson et al. showed that the temperature of thermophilic heap leaching of a chalcopyrite concentrate could increase to 70 °C while successively introducing various mesophile and thermophile cultures, and that copper extractions in excess of 90% were achieved within 100 days. The activity of microorganisms in the …
Heap Leaching: Modelling and Forecasting Using CFD …
Heap leaching of low grade complex copper sulphide ore bodies must contend with slow leach ... evaporation, temperature X X+ internal liquid freezing Copper sulphide ores have complex minerology and complex leaching behaviour, including oxidation, bacteria effects, gangue and precipitation. Watling [34] gives a review of the bioleaching
Heap Leaching: Modelling and Forecasting Using CFD Technology …
Figure 8 shows the thermal contours within the heap at 17 months; regions of high temperature within the heap develop in areas where the leaching agent is reacting with pyrite and chalcopyrite minerals. In both simulations, the temperature in the reaction zones of the heap reached in excess of 45 °C.
(PDF) Copper heap leaching: Process, principles and …
Heap leaching generates a pregnant leach solution (PLS) containing 1–6 g/L Cu²⁺, which is sent to solvent extraction and electrowinning for copper production.