— Heap and dump leaching tend to be the technologies of choice for low-grade secondary copper sulfide ores and, to a much less extent, primary copper sulfide ores such as chalcopyrite (Domic, 2007). Sulfide minerals in heaps and dumps represent natural habitats for acidophilic microorganisms but there is limited information on those that …
— If copper recovery depends on (1/d p) and the copper leaching rate depends on (1/d p) 2, leaching of ROM ore in dumps should be impossible, or at least so slow and marginal as to not be profitable. And yet dump leaching of copper secondary sulphides is practiced widely, with good recoveries and at rates rapid enough to be measurable ( …
— This paper takes the generally accepted assumptions by operators about lixiviant flow in the unsaturated heap leach ore and exposes the myths and corrects the misunderstandings.
Heap leaching is most commonly found in the gold and copper industries, but is also gaining acceptance amongst a variety of other materials as well, including: Silver; Uranium; Nickel; Zinc; Rare Earths; What the Heap Leaching Process Looks Like: Crushing & Agglomeration. In heap leaching, mined ore is first commonly crushed in order make the ...
— The use of heap leaching for primary copper mineralization is now advancing rapidly with the goal of avoiding the costly grinding necessary to prepare …
Physicochemical Problems of Mineral Processing, 42 (2008), 29-36 ... Heap leaching of oxide copper ores and cathode copper recovery by solvent extraction (SX) and elec-
— The drum agglomeration is considered as a pretreatment step for the heap leaching of copper and gold ores whereas the agglomeration of uranium and nickel ores has received less attention over the past years. ... nickel, silver and gold ores. Several heap leach operations have experienced problems associated with poor recovery due to …
— PDF | Heap leaching technology is finding increasingly widespread application to recover values from low-grade ores, especially in the gold and copper... | Find, read and cite all the...
— Heap leaching is a low-cost technology used in industrial mining to recover precious metals such as gold and uranium, along with several other highly sought after metals like copper, from their primary resources (ores and minerals). For many decades, there has been a growing demand for heap leaching due to its environmental benefits. …
— 1. Introduction. Heap leaching is a low-cost, flexible hydrometallurgical process for recovering valuable metals from low-grade ores (Nosrati et al., 2012).In this process, the ore bed must be porous and permeable to permit flow of the leach solution (Lewandowski and Kawatra, 2009a).However, fine particles usually migrate into the …
— General structure of the heap leaching system obtained for the ore grade analysis by the Disjunctive and Mellado model. H1, H2, H3, and SX denote the heap 1, 2, 3, and the solvent extraction unit ...
Heap leaching is the most important method of hydrometallurgical copper extraction. Heap leaching is used for treating oxide and lower-grade secondary sulfide ores that contain …
leach pads in Western Montana and Southern California in 1979. Geomembrane lined copper heap leach pads started in Mexico and Arizona as early as 1983, however the copper heap leach dump operations have gradually changed to geomembrane lined foundations and interlift liners within the last 5 to 10 years. An early geomembrane lined …
— Heap leaching has been implemented in different mining operations in order to recover copper, gold, and uranium. It has been especially cost-effective for treating low-grade ores [1,2,3,4]. In particular, the heap leaching method to treat copper ores has been used in Chile since the 1980s. It currently produces over 1.5 Mt/year of cathodes ...
— Leaching of copper from a Jordanian copper ore has been studied using a stirred batch reactor with hydrochloric acid as the main lixiviant, under the following conditions: temperature 25 – 45 oC ...
— Heap leaching is done on ores of semilow grade—that is, high enough to be brought to the surface for treatment. This method is increasing in popularity as larger tonnages of semilow-grade ore are mined. The ore is piled in heaps on pads and sprayed with leach solution, which trickles down through the heaps while dissolving the values. …
The primary disadvantages of heap or dump leaching as compared to milling are. Lower metal recovery, Longer process time, Slow response to process changes, and. No by …
— In situ leaching offers a potentially attractive way to extract copper from the subsurface without costly fragmentation and processing. Applicability of in situ leaching is limited to deposits where sufficient permeability exists and where the copper and gangue mineralogy is amenable to leaching. A key challenge from past projects is establishing …
— 1. Introduction. Heap leaching forms part of the group of technologies known as percolation leaching, which includes in situ leaching, dump leaching, heap leaching and vat leaching (Bartlett, 1998, John, 2011)mon to all these technologies is migration of leach solution through a fixed bed of ore particles, on its path interacting with the solid, …
— The design and planning of heap leaching systems is a coupled problem. Padilla et al. ... This section illustrates the application of the model for the copper heap leaching process in systems of one, two and three heaps to analyze the effects of variables such as copper price, heap size, ore grade, acid price and variable cost on the process ...
Crushed ore heap leaching involves reducing ROM ore to a predetermined optimal target size distribution, sometimes with topsizes as small as 12.5 mm (0.5 in.) or even finer through ... and copper ores, whereas heap leaching has been applied to many different minerals including copper, gold, silver, ura-nium, vanadium, zinc, nickel, and cobalt ...
— Although the main cause of hydrometallurgical plant closures is the depletion of oxidized copper minerals reserves, the lack of new hydrometallurgy projects also contributes to these closures. One solution is to be able to process copper sulphide ores hydrometallurgically. However, it is widely known that sulphide copper ores—and …
The leaching reagent (dilute sulfuric acid) is sprayed through sprinklers on top of the heap pile and allowed to trickle down through the heap, where it dissolves the copper from the ore. The resulting "pregnant" leach solution of sulfuric acid and copper sulfate is collected in a small pool. The copper compound can now be seen at ...
— Problems with copper heap leaching may arise from the ore mineralogy, more specifically, the presence of reagent consuming gangues and clays minerals.
— Heap leaching for rare earth elements poses a serious long-term threat to the adjacent ecological systems in mining areas. The purpose of this research is to thoroughly study the environmental effects of heap leaching in ion-adsorption rare earth element mine tailings after restoration by ecological measures. Soil samples were …
If there are no other economic elements within the ore a mine might choose to extract the uranium using a leaching agent, usually a low molar sulfuric acid. Similar to copper oxide heap leaching, also using dilute sulfuric …
In this study, weak acid in the curing and leaching stages of copper ore was incorporated, and we analyzed its effect on the dissolution of copper and final impurities. The weak acid corresponds to a wastewater effluent from sulfuric acid plants produced in the gas treatment of copper smelting processes. This effluent is basically water with high acidity (pH-value …
— Heap leaching is a well-established extractive metallurgical technology enabling the economical processing of various kinds of low-grade ores, which could not otherwise be exploited.
— 1. Introduction. The global trend towards industrialization supports the increasing demand for industrial metals. It is in this context that low-grade and complex ores, old waste deposits related to past mining worksites and other sources have received attention in recent years, with the latest advances in leaching techniques and …
— Sulfuric acid solution containing ferric iron is the extractant for industrial heap bioleaching of copper sulfides. To start a heap bioleaching plant, sulfuric acid is usually added to the irrigation solution to maintain adequate acidity (pH 1.0–2.0) for copper dissolution. An industrial practice of heap bioleaching of secondary copper sulfide ore …
— The dissolution of carbonate gangue minerals, which are often ubiquitous in copper deposits, leads to the consumption of large amounts of acid during the leaching of such ores, which can make the process uneconomical (Habashi, 1970, Habashi, 1980, You-Cai et al., 2013).Table 1 shows the acid consumption and estimated time to complete …
— To those of us in the gold industry, the question "What is heap leaching?" seems to have an obvious answer. In the simplistic sense, heap leaching involves stacking of metal-bearing ore into a heap on an impermeable pad, irrigating the ore for an extended period of time (weeks, months, or years) with a chemical solution to dissolve the sought …
— PDF | The theory and practice of copper and gold heap leaching | Find, read and cite all the research you need on ResearchGate
