Copper Sulfide Ore Research Articles

230Th/U Chronology and Geochemistry of Irinovskoe Hydrothermal Field (Mid-Atlantic Ridge)

The results of 230Th/U dating and mineralogical–geochemical studies of sulfide ores from the Irinovskoe hydrothermal field and the Severo-Zapadnoe ore occurrence (Mid-Atlantic Ridge) are presented. Sulfides are represented primarily by copper–sulfide ores with 12–30% Cu content; sulfur- and zinc-sulfide ores are distributed less frequently. The analysis of a change in the composition of sulfides over time has made it possible to identify three stages of formation. Each stage assumes that mineral associations are changed from high-temperature (sulfur and copper sulfide) to medium temperature (Zn–Cu and Zn-sulfide) sulfide ores. The whole age range of formation of the hydrothermal deposits falls within the time interval of about 58000–8000 for the Irinovskoe field and 69000–11000 years ago for the Severo-Zapadnoe ore occurrence.

Adsorption and flotation of copper sulfide ore with diisopropyldithiophosphate collector

The results of investigation adsorption mechanism of diisopropyldithiophosphate collector on the surface of the sulfide copper ore and flotation has been discussed. The investigation of composition and structure of sulphide copper ore has been carried out by using FT-IR-spectroscopy, Х-ray diffraction spectroscopy and ICP-MS method. The results showed that sorption capacity of ore at pH 10.5-11.5 is a maximum. The role of the oxidation-reduction processes in fixing of diisopropyldithiophosphate ion on the surface of ore was established. It was shown that data of extraction of copper to concentrate and adsorption value of diisopropyldithiophosphate ion are correlating. The IR-Fourier spectroscopic analysis showed that collector is coordinated with the ions of the metal of the crystal lattice of copper-containing minerals through the sulfur atoms of the dithiophosphate group.

ABRASIVENESS EVALUATION OF PRE-CONCENTRATION OF COPPER SULFIDE ORE PRODUCTS THROUGH LCPC TEST

Ore abrasiveness is usually quantified through the Bond Abrasiveness Index (AI), which is based on the capability of a material wearing out and polishing other materials. This index finds widespread application in the assessment of how much wear a given ore is set to cause in ore processing equipment. Several test methods may be used to determine ore abrasiveness, but the Bond Method is the one most frequently used in the mining industry. Despite being simple, this test has certain limitations as to grain size and required amount of ore sample, which very often makes it difficult or even impossible to apply it in the early stages of a project, geometallurgical and pre-concentration laboratory studies. The LCPC test may offer an alternative, as it requires a smaller amount of fine-grained material. The core objective of this study is to use the LCPC test to evaluate the abrasiveness index of a copper sulfide ore that went through a pre-concentration process. One of the findings is that the pre-concentration process produced a concentrate whose abrasiveness is lower than that of the feed, which helps enhance the pre-concentration gains, in addition to the expected gain by reducing the mass and increasing the grade of ore to be fed into the mill.

Application of ecofrendly oxidant ferrate(vi) in the metallurgical processes of copper extraction

This works deals with investigation the efficiency of sodium ferrate, Na 2 FeO 4 , obtained by the elec-trochemical oxidation, as coagulation and flocculation agent for purification of wastewater from the electrolytic refining process from the Bor Copper Refinery and Copper Smelter Plant of the Mining and Smelting Combine Bor. Removal of heavy metals and selenium by barium ferrate in aqueous solutions could be possible up to: 100 % for Cu, 97.18 % for As, 98.37 % for Sb and 6.06 % for Se using fer-rate(VI) in the ratio M : Fe(VI) = 1:12. Also, the efficiency dependence of copper sulphide ore leaching from concentrate by the oxidation of copper sulfide and chalcopyrite with ferrate(VI) on the sulphuric acid concentration was investigated in this work. It is found that leaching of copper from vthe copper sulfide concentrate, carried out by fer-rate(VI), proceeds easily due to the efficient oxidation of sulfide and sulfur, in respect of the classical acid process that usually needs the addition of strong oxidant, such as oxygen or hydrogen peroxide, to increase the process productivity.

Bacterial Leaching of an Indonesian Complex Copper Sulfide Ore Using an Iron-Oxidizing Indigenous Bacterium

The bioleaching of an Indonesian complex copper sulfide ore was studied in shake flasks over a period of 14 days using an iron-oxidizing indigenous bacterium at room temperature (28 oC) and various pulp densities (5% and 20%). The bioleaching suspensions were periodically analyzed for Cu and Fe concentrations as well as Eh, pH and DO values. Cu bioleaching efficiencies at 5% pulp density were higher than those at 20% pulp density, which correlated with Fe concentration in solution. Over a period of 14 days, the pH of bioleaching suspension was in the range of 5 ~ 9, indicating that Cu bioleaching was greatly influenced not only by proton H+ dan ferric ion but also by extracellular polymeric substances (EPS) generated by the bacterium. The current study may improve our better understanding on the bacterial action for bioleaching of complex copper sulfide ores that remains debated so far as refractory ores.

Effect of Pretreatment on Leaching Primary Copper Sulfide in Acid-Chloride Media

The aim of this study was to improve the dissolution of copper sulfide ore composed mainly of chalcopyrite (1.21 wt %) and bornite (0.54 wt %) using a pretreatment before leaching. The effect of the pretreatment on copper sulfide dissolution was investigated using different types of leaching. Three sets of experimental tests were performed (flask, reactor and mini-column). Using experimental design, three operational variables in the ore pretreatment were evaluated: chloride concentration (20, 50 and 90 kg/t), repose time (7, 20 and 40 days) and repose temperature (20 and 50 °C). A maximum of 93% copper dissolution was obtained when the ore was treated with 90 kg Cl−/t ore, 40 d of repose time and 50 °C in flask leaching. Without any ore pretreatment, 53% copper dissolution was achieved. Using reactor leaching, an 85% copper dissolution was obtained using pretreatment stage. Without this pretreatment, only 55% copper dissolution was obtained. The final test, which involved leaching a pretreated ore in a mini-column at room temperature, yielded 49% copper dissolution. The data showed that repose time and temperature were the most important variables affecting copper extraction in the pretreatment stage. This study indicates that pretreatment has a positive effect on copper dissolution from primary copper sulfide ore in an acid-chloride medium. It also provides a feasible alternative for treating primary copper sulfide ores at the industrial level.

EVALUATION OF THE ROUGHER FEED AND CONCENTRATE SIZE DISTRIBUTIONS FROM THE SALOBO SULPHIDE COPPER ORE PROCESSING PLANT

Salobo plant processes a gold and copper sulfide ore. The flotation process comprises the rougher, cleaner, and scavenger stages. Concentrate from the rougher and scavenger stages goes through a regrinding process before being fed into the cleaner stage. During the first years of operation, it was noticed that the regrinding feed size was consistently finer than expected, even though the flotation feed size (rougher stage) was within the planned parameters and significantly coarser than the concentrate from the rougher stage. This paper describes the results of field samplings and laboratory tests carried out to identify the factors behind such difference and to quantify it. Moreover, it shows the impacts of such size difference on the concentrate regrinding stage.

Characterization of a low-grade copper-sulphide ore to assess its suitability for in situ recovery

CSIRO Minerals is developing new technologies and approaches for the in situ recovery (ISR) of valuable metals. ISR provides opportunities to process small and/or deep deposits and could create additional revenue for conventional uneconomic mines. Unlike for conventional processing, no standard methodology exists for characterizing sample suitability for ISR. The authors are developing a workflow to understand sample and deposit amenability to ISR processing. A South Australian low-grade iron-oxide-copper-gold sulphide ore was studied. A total of 37 drill cores samples were obtained from the ore sample for detailed mineralogical and leaching characterization. A range of characterization techniques including chemical analysis, X-ray fluorescence mapping, quantitative evaluation of minerals by scanning electron microscopy, computed tomography scanning, and bulk- and micro-X-ray diffraction analyses were applied to understand the ore mineralogy. Leaching tests at 50 °C were performed on selected samples to understanding their leaching behaviour. Mineralogical characterization found that copper was present mostly as discrete secondary copper sulphides distributed in various areas and at various specimen depths, which, in theory should be readily available for leaching, provided sufficient solution access exists. Leaching results showed steady copper recovery under the conditions tested. This study provides insight into understanding the suitability of an ore for ISR processing.

Rare metals behavior during the processing of off-balance copper-sulfide ores

Rare metals behavior during the processing of off-balance copper-sulfide ores

Sorption of Rhenium from Sulfuric Acid Solutions with Trialkylamine-Containing Impregnates

The sorption of rhenium (VII) from sulfuric acid solutions with impregnates based on macroporous polymeric carriers (copolymers of styrene with divinylbenzene, a weakly acidic cation-exchange resin), which contain technical trialkylamine (TAA), is investigated in batch conditions. Equilibrium and kinetic characteristics of sorption of rhenium with the K-TAA impregnate based on macroporous cationite having the best capacitive characteristics with respect to rhenium are found. The maximal distribution coefficient of rhenium in the K-TAA impregnate is observed during sorption from solutions with pH 2. The sorption isotherm of rhenium is described by the Langmuir equation with constant K = 29 ± 2 mL/g. Integrated kinetic curves of sorption are found by the method of a limited solution volume at various temperatures and effective diffusion coefficients of rhenium in an impregnate, which are equal to 3.8 × 10–11 (295 K) and 1.3 × 10–10 (308 K) m2/s, are calculated allowing to the half-transformation time. Processing the kinetic data by linearization according to equations of models of the pseudo-first, pseudo-second, internal diffusion, and Elovich showed that kinetic curves are described with the highest degree of correlation by pseudo-second-order equations with rate constants 0.00056 (295 K) and 0.00059 (308 K) g mg–1 min–1. The apparent activation energy of sorption of rhenium of 39 ± 2 kJ/mol is calculated according to the Arrhenius equation. The K-TAA impregnate is approved for the sorption of rhenium from the eluate formed during the desorption of rhenium from the weakly basic anion-exchange resin (Purolite A170) preliminarily saturated with rhenium from a productive leaching solution of processing products of rhenium-containing off-balance copper-sulfide ores with a complex composition.

Complete genome sequence of Acidihalobacter prosperus strain F5, an extremely acidophilic, iron- and sulfur-oxidizing halophile with potential industrial applicability in saline water bioleaching of chalcopyrite

Successful process development for the bioleaching of mineral ores, particularly the refractory copper sulfide ore chalcopyrite, remains a challenge in regions where freshwater is scarce and source water contains high concentrations of chloride ion. In this study, a pure isolate of Acidihalobacter prosperus strain F5 was characterized for its ability to leach base metals from sulfide ores (pyrite, chalcopyrite and pentlandite) at increasing chloride ion concentrations. F5 successfully released base metals from ores including pyrite and pentlandite at up to 30gL−1 chloride ion and chalcopyrite up to 18gL−1 chloride ion. In order to understand the genetic mechanisms of tolerance to high acid, saline and heavy metal stress the genome of F5 was sequenced and analysed. As well as being the first strain of Ac. prosperus to be isolated from Australia it is also the first complete genome of the Ac. prosperus species to be sequenced. The F5 genome contains genes involved in the biosynthesis of compatible solutes and genes encoding monovalent cation/proton antiporters and heavy metal transporters which could explain its abilities to tolerate high salinity, acidity and heavy metal stress. Genome analysis also confirmed the presence of genes involved in copper tolerance. The study demonstrates the potential biotechnological applicability of Ac. prosperus strain F5 for saline water bioleaching of mineral ores.

Recovery of Copper from Pyritic Copper Ores Using a Biosurfactant-Producing Mixotrophic Bacterium as Bioflotation Reagent

In an attempt to investigate the use of bacteria and their metabolites as bioflotation reagents for environmentally friendly mineral processing, laboratory cell flotation tests were carried out using copper sulfide ores bearing a high content of pyrite, which were mixed with a biosurfactant-producing mixotrophic bacterium as bioflotation reagents. The interaction of bacterial cells and their metabolic products with the sulfide ores resulted in the alteration of the surface chemistry of both ores and bacterial cells as evidenced by FTIR and SEM-EDS observations as well as surface tension and contact angle measurements. The change in the surface properties of the sulfide ores in turn enabled the bacterium to function as flotation bioregeants in the flotation of copper sulfide ores as a function of bacterial cell concentration, conditioning time, flotation time and pH. Overall, the bacterium and its metabolites as bioreagents yielded flotation recoveries which might be attributed to the multi-function of the bacterium as depressant, collector and frother. Thus, the bacteria tested in this study could potentially be used as flotation bioreagents, providing an alternative to conventional flotation reagents.

The Impact of Heap Self-Heating on Microbial Activity during the Bioleaching of Low-Grade Copper Sulfide Ores

In this study, a dynamically-controlled column was used to evaluate two ores known to cause heap overheating. This enabled the simulation of heap self-heating under controlled conditions. The lixiviant was inoculated with a consortia of mesophilic and moderately thermophilic microorgaisms, and the impact of rapid temperature increases on biological activity and cell numbers was evaluated. During the leaching of ore sample A, the temperature lagged for 29 days before increasing rapidly from 26 to 88 °C. Cell numbers and solution potential increased concomitantly, before both were reduced as the temperature increased past maximum microbial tolerances. Cell numbers began increasing again within 10 days of reaching temperatures that would facilitate mesophilic growth being restored. During the leaching of ore B, the temperature lagged for 4 days before exhibiting a rapid increase in temperature, increasing from 30 to 76 °C over a six-day period. Cell numbers were reduced with the sudden temperature increase, and did not recover over the remainder of the experiment.

Bio-Heap Leaching of Primary Copper Sulfide Ore by JOGMEC

JOGMEC has been carrying out the study on primary copper sulfide ores leaching for recovering copper economically and efficiently by heap leaching. In our study, we have been using the primary copper sulfide ore produced in an IOCG deposit. The ore is characterized by high iron content and high acid consumption in leaching. For the optimization of the leaching, the conditions such as ore size, agglomeration, pH and irrigation rate of leaching solution were examined with column leach tests. The best result was over 80 % extraction of copper in 150 days with leaching solution of 1 M sulfuric acid and temperature of 45 °C. In this experiment, the fines of the ore sample were removed before putting it into the column to keep the permeability of the ore bed. In these column leach tests, the Fe2+/total-Fe ratio of PLS decreased gradually by the activity of naturally grown iron-oxidizing bacteria. The bacteria in PLS, which have the ability of iron-oxidizing and sulfur-oxidizing, were identified by next-generation sequencing as Acidithiobacillus caldus and Sulfobacillus thermosulfidooxidans. We also carried out bench-scale tests with about 200 tons of the primary copper sulfide ores. Iron-oxidizing and sulfur-oxidizing bacteria were identified in the leaching solution as same with column leach tests. It is considered that the bacteria worked in the leaching solution and on the surface of the ores.

Kinetic modeling of copper bioleaching from low-grade ore from the Shahrbabak Copper Complex

The copper recovery from low-grade copper sulfide ore was investigated using microbial leaching. Several parameters substantially affect the bioleaching of copper; among them, pulp density and nutrient media were selected for investigation. The optimum conditions for copper recovery were a pulp density of 5 g/mL, a mixed-mineral salt medium of Acidithiobacillus thiooxidans (70vol%) and Acidithiobacillus ferrooxidans (30vol%), and 10vol% of inoculum. Under these conditions, the maximum bioleaching capacity of the medium for copper recovery was determined to be approximately 99%. The effect of pulp density on the kinetics of the bioleaching process was surveyed using both da Silva’s method and constrained multilinear regression analysis. The kinetics of copper dissolution followed the shrinking core model, and the process was diffusion controlled at a pulp density of 5 g/mL. Nevertheless, at higher pulp densities, the process was controlled by chemical reaction.

Calibrated X-ray micro-tomography for mineral ore quantification

Scanning Electron Microscopy (SEM) based assessments are the most widely used and trusted imaging technique for mineral ore quantification. X-ray micro tomography (XMT) is a more recent addition to the mineralogy toolbox, but with the potential to extend the measurement capabilities into the three dimensional (3D) assessment of properties such as mineral liberation, grain size and textural characteristics. In addition, unlike SEM based assessments which require the samples to be sectioned, XMT is non-invasive and non-destructive. The disadvantage of XMT, is that the mineralogy must be inferred from the X-ray attenuation measurements, which can make it hard to distinguish from one another, whereas SEM when coupled with Energy-Dispersive X-ray Spectroscopy (EDX) provides elemental compositions and thus a more direct method for distinguishing different minerals. A new methodology that combines both methods at the mineral grain level is presented. The rock particles used to test the method were initially imaged in 3D using XMT followed by sectioning and the 2D imaging of the slices using SEM-EDX. An algorithm was developed that allowed the mineral grains in the 2D slice to be matched with their 3D equivalents in the XMT based images. As the mineralogy of the grains from the SEM images can be matched to a range of X-ray attenuations, this allows minerals which have similar attenuations to one another to be distinguished, with the level of uncertainty in the classification quantified. In addition, the methodology allowed for the estimation of the level of uncertainty in the quantification of grain size by XMT, the assessment of stereological effects in SEM 2D images and ultimately obtaining a simplified 3D mineral map from low energy XMT images. Copper sulphide ore fragments, with chalcopyrite and pyrite as the main sulphide minerals, were used to demonstrate the effectiveness of this procedure.

Leaching kinetics of a Nigerian complex covellite ore by the ammonia-ammonium sulfate solution

Hydrometallurgical treatment of copper sulfide ore is increasingly establishing itself as a feasible route for the extraction of copper and recovery of associated precious metals value. This is attributed to the merits of this route, which include suitability for low-grade and complex ores, high recoveries, competitive economics, and other operational features. The leaching kinetics of Nigerian complex covellite ore was investigated in ammonia-ammonium sulfate solution. The concentration of ammonia and ammonium sulfate, the ore particle size, and the temperature were chosen as parameters in the experiments. The results show that temperature, concentration of ammonia-ammonium sulfate has favorable influence on the leaching rate of covellite ores; however, leaching rate decreases with increasing particle size. At optimal conditions (1.75mol/L NH4OH+0.5mol/L (NH4)2SO4, −90+75 μm, 75 °C, with moderate stirring) about 86.2% of copper ore reacted within 120 minutes. The mechanism of the leaching was further established by characterizing the raw ore and the leached residue by EDXRF - chemical composition, SEM - structural morphology and XRD - phase identification studies. From the X-ray diffraction analysis, the partially unreacted Cu and S phases were presumed to be CuO, and the iron present in the CuS phase was mainly converted to hematite (Fe2O3·H2O), as the CuS phase disintegrated and remained in the residue afterward.

Selective recovery of copper and zinc from mine dump waters of mining enterprises in precipitates

The acid mine dump waters at mining companies that mining the copper and copperzinc sulphide ore have the high concentrates of metals and classified in our view as the raw materials for selective recovery of metals in precipitates comparable in quality with concentrates of ores enrichment and suitable for further metallurgical processing. Authors have implemented three two-stage schemes for sequential extraction of copper and zinc: cementation-sulphide precipitation, galvanocoagulation-sulphide precipitation, precipitation-precipitation. Moreover, parameters of processes and quality of the obtained precipitates have described. The achieved copper recovery is 89% and 94% respectively with the application of cementation and galvanocoagulation, in sulphide precipitate exceeded 75%. Furthermore, the copper recovery from decoppering in precipitates amounted to more than 65%. Zinc-containing precipitates because of coprecipitation of iron, magnesium and calcium contain zinc from 14% to 28%, in two to three times less than the quality of conditioned zinc concentrates. The content of precipitates allows to apply them for additional charging to concentrates of enrichment or for the production of metals in metallurgical treatment. As a result of the studying the effect of reduced total salinity (S) on mass fraction of zinc in precipitate (β) with the constant concentration of zinc (SZn), the changes in concentration with constant salinity and reduction in total salinity (S) with constant ratio S/CZn, the following dependencies have obtained: , in the range of an index S from 4.5 to 90.0 g/L , where is a partial derivative of x to y, whereas the value z is fixed.

Flotation of an Oxidized Copper Sulfide Ore

Flotation of an Oxidized Copper Sulfide Ore

Co-production of gold from sulfide copper and copper-zinc ores

Co-production of gold from sulfide copper and copper-zinc ores