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Showing 1 to 20 of 21 for “"Heap leaching"”.
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Effects of adding acid plant sulfur on heap leaching
… ore deposits are found across the world and heap leaching of copper has been implemented effectively for years. The ore is broken down to copper ions and elemental sulfur in the heap. Acid plants are used in mines to replenish the raffinate leaching the heaps which consists of sulfuric acid. …
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Effect of scale of operation on heap leaching performance
… contribute towards the differences observed in leaching performance between laboratory-scale columns versus commercial-scale heaps was investigated. Furthermore, the contributions of segregation and stratification, which are absent from columns but unavoidable in heaps, were also investigated. …
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Fundamental studies of heap leaching hydrology using magnetic resonance imaging
The recovery of mineral from ore in the heap leaching process requires the mineral to come into contact with the leaching solution. However, heap hydrology is prone to non-uniform behaviour due to the inhomogeneity of the ore particles and the heap structure. The primary aim of this thesis was …
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Acid biodesulphurisation of coal discards using a heap leaching approach
… acidity and precipitate metal pollutants. Heap bioleaching, a technology commonly used in recovering base metals from low-grade metal sulphide ores, offers a sustainable approach to accelerate the reaction of pyritic fractions within coal discards. This method enables the removal of …
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Residence time investigation of artificial silver ores in heap leaching using cyanide lixiviant
Heap Leaching has gained much relevance in the processing of low-grade mineral resources - ores considered uneconomical for beneficiation through conventional concentration and tank leaching. However, it is at the same time characterized by extended leaching periods due to slow mineral conversion …
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Properties governing the flow of solution and air through crushed ore for heap leaching
Heap leaching is used extensively for the processing of low-grade copper and gold ores. Heap leaching of low-grade ores is often restricted by the hydrology of the bed, which limits the rate of dissolution of the target mineral. If the ore has low permeability, it may lead to underperformance or …
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An investigation of cyanide-based heap leaching for extracting precious metals from Platreef ore
Cyanide heap leaching had been proposed as an alternative to the classic crush-mill-loatsmelt-refine route for processing platinum group metals (PGMs) from the Platreef ore body. Overall the process includes two stages of leaching. The first stage involves the thermophile bioleaching of the base …
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Application of HPGR and X-Ray CT to investigate the potential of Witwatersrand gold ore for heap leaching : a process mineralogy approach
… processing options have become limited. Heap leaching is a well-established technology which continues to grow in use and provides several benefits to solve some of these problems. High pressure grinding rolls (HPGR) is another technology with significant potential, especially for its …
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The art of soaking rocks: systematic study of liquid and solute flow in packed rock beds in the context of heap leaching
[Abstract has formulas not accommodated by DSpace]
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On the progression of leaching from large particles in heaps
Although heap leaching is by now a well-established technology choice in the mining industry, the process remains limited by low recoveries and long extraction times. It is becoming increasingly clear that the successful application of heap leaching technology will ultimately depend on having a …
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The anodic dissolution of covellite in acidic, chloride solutions
… in an apparatus, which was designed to resemble leaching of the mineral under conditions applicable to heap leaching of whole ores, where the mineral occurs in cracks or pores in the gangue matrix or is covered (or partially covered) by reaction products.
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Base metal heap and tank leaching of a platreef flotation concentrate using ammoniacal solutions
The technical feasibility of the ammonia leaching process of a Platreef flotation concentrate was investigated in different reactor settings i.e. shake flasks, columns and batch stirred tank reactors, respectively. The process investigated aims to use either a heap leaching environment or tank …
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A techno-economic comparison of three process routes for the treatment of Gamsberg zinc ore
… (SHG) zinc (>99.995% Zn). These routes include heap leaching and refining locally (route 1), preparing a flotation concentrate and refining it locally (route 2) and lastly, preparing a flotation concentrate and shipping it for toll refining in Europe (route 3). Zinc heap leaching has not yet …
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Hydrometallurgical Processing Of Rare Earth Elements From Ion Adsorption Clays
The surface mining and heap leaching of China's ion-adsorption rare-earth resources have caused severe environmental damage, there is a need to better understand Rare Earth leaching from Clay ore with the use of agglomerates that improve the permeability of the ore during heap leaching operation. …
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Effects of intermittent irrigation on the extraction of copper from heap bioleaching systems.
… for the regeneration of leach agents in the heap leaching of mineral sulfide ores is finding increasing application as a hydrometallurgical unit operation applicable to the treatment of the increasing low grade ores. These same microorganisms contribute to the formation of acid rock drainage …
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On the leaching behavior of uranium-bearing resources in carbonate-bicarbonate solution by gaseous oxidants
… method of extraction is developed. Alkaline leaching of uranium from limestone media has been practiced extensively in the past; however, cutting-edge research during the last 20 years has been rather meager. The research reported in this thesis is an investigation into the use of an …
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Comparison of non-reactive solute transport models for the evaluation of fluid flow in leaching beds
Heap leaching is a hydrometallurgical process used for the extraction of minerals within complex and typically low-grade ores. An important factor in the mineral dissolution process is the contact efficiency between the irrigation fluid (lixiviant) and the targeted mineral, which is influenced by …
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Numerical and Experimental Analysis of the Effect of Faults in Open-Pit Mining Stability
… Hydro-Jex® is a new enhanced method for heap leach treatments with significantly higher mineral recovery. In this study, the Hydro-Jex operation is case-studied at the Los Filos mine in Mexico for heap leach stability. This is pursued by numerical modeling of the heap leach pad stability …
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Investigating variables affecting heap (bio)leaching through determining access to sub-surface mineral grains by micro-scale X-ray tomography
Heap bioleaching is a hydrometallurgical technology, used to facilitate the extraction of valuable metals such as copper, gold, nickel and uranium from low-grade, typically sulphidic, ores. The process is highly complex as it is influenced by interactions of different sub-processes including flow …
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Assessment and modelling of chromium release in minerals processing waste deposits
… present work, building on an existing model for heap leaching, which, conceptually, is very similar to the leachate generation process. The model is based on the continuity equation formulated for reaction-diffusion processes at the level of an individual porous particle and for …
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