Sulfide Research Articles

Effect of zinc process water recycling on galena flotation from a complex sulphide ore

The effects of utilizing recycled tailings pond water from the flotation plant at the Mining Company of Guemassa (MCG) on galena recovery and selectivity towards chalcopyrite (RPb-Cu) , sphalerite (RPb-Zn), and pyrrhotite (RPb-Fe) were studied at bench scale. The results showed that recycling the tailings pond water in the lead circuit without addition of fresh water gave a good flotation performance in terms of lead recovery (Rpb) (75%) and selectivity towards the other metals: RPb-Cu (54%), RPb-Zn (60%) and RPb-Fe(65%). This allows the water to be recycled at least four times. However, increasing the d80 from 100 um to 160 um currently used at the MCG plant had a negative effect on the lead flotation performance.

In situ Raman investigation of dissolved constituent and its evolution in pulp during Zn-S selective flotation with two-step pulp regulation

Redox potential (Eh) of the pulp dominates Zn-S selective flotation, and regulating Eh can maximize Zn grade and recovery of Zn rougher concentrates. However, reasons accounting for the beneficial results of Eh regulation in flotation have not been previously elucidated. This study investigated the inherent causes of macro flotation results by inductively coupled plasma optical emission spectrometer (ICP-OES), Raman spectra and X-ray diffraction (XRD) analyses. The ICP-OES data showed that the levels of calcium and sulfur in the pulp increased considerably after lime regulation. The Raman spectra confirmed that calcium polysulfide (CaSn, n = 2–8) was generated and maintained long-term stability in the pulp regulated by lime without Eh regulation. However, under Eh regulation, CaSn only kept momentary existence in the pulp. Polysulfide reacted quickly with the added copper sulfate and formed brown precipitates, whose main component identified by XRD was CuS, leading to the ineffectiveness of copper-activation for Zn flotation. These findings provide a new insight into the role of Eh in sulfide mineral flotation and partially explain the main reasons to hinder the high-efficiency selective separation of sphalerite from pyrrhotite-containing sulfide ores.

Filizchay pyrite-polymetallic deposit (the southern slope of the Greater Caucasus) – as a typical representative of the SEDEX type pyrite deposits


 
 
 The article has been devoted to one of the largest deposits of the southern slope of the Greater Caucasus – the Filizchay pyrite-polymetallic deposit. It has been found that the main morphology peculiarity of the pyrite-polymetallic deposit of the Filizchay deposit is that it is a single, compact sheet-like body composed mainly (at 90-95%) by the aggregates of the sulfide ores which are based on pyrite, sphalerite, galena and to a far lesser extent chalcopyrite and pyrrhotite. The carbonate minerals played a subordinate role in the deposit composition and quartz, sericite and chlorite – even less. The pyrite –polymetalic ores of the deposit are characterized by the following main mineralogical-textural varieties of ores: layered-bedded pyrite-polymetallic, massive sulfur-pyrite, massive pyrite-polymetallic, spotted-disseminated pyrite-polymetallic and vein-disseminated pyrite-polymetallic. The vein-disseminated ores are adjacent to the deposit on the footwall and are considered as independent bodies. Two industrial-techno- logical types of ores, oxidized and pyrite-polymetallic, have been distinguished at the deposit. The latter is in turn divided into two grades: mixed and primary ores. These three varieties of ores differ in the content of the oxidized lead forms. The ores with a content of the oxidized lead speciation above 60% have been classed as oxidized ores, those from 20% to 60% as mixed and those below 20% as primary. The Filizchay deposit consists of thin-bedded massive sulfides with shales, siltstones or sandstones interbeds («ore flysch») which have been formed exclusively or mainly as a result of the exhalative processes on the seabed and differ from massive sulfide deposits in volcanic rocks. On the basis of this and also according to the geological structure, the reserves of the valuable Zn + Pb components of the deposit belong to the SEDEX type that is the most important source of lead, zinc and silver. The deposit had been developing for a long time starting from the period of sedimentation and up to the ore’s formation of the copper-pyrrhotite stage. The lower age limit of the mineralization is determined by the presence of the hydrothermal-sedimentary ores of the Upper Pliensbachian. The upper age limit is established by the presence of the pebbles of the hydrothermally altered rocks and by their sulfide ores in the conglomerates underlying the deposits of the lower parts of the Upper Jurassic.
 
 

Paragenetic Association of Platinum and Gold Minerals in Placers of the Anabar River in the Northeast of the Siberian Platform

Areal placers of diamond and precious metals (platinum and gold) of unknown origin are widespread in the Anabar River basin on the northeastern part of the Siberian Platform. This article discusses the typomorphic features of palladium gold (porpezite) and ferroan platinum, which, in addition to fragmented individual grains, sometimes form close growths, which indicates their obvious genetic relationship. This can be used to delimit the primary sources of commercial components of complex placers by their genetic types. The composition of minerals was determined on a Camebax-Micro (Cameca, France) microprobe analyzer, and their microstructural relationships were studied using the scanning microscope JSM-6480LV JEOL. Determination of the structure and parameters of elementary lattices of minerals was carried out on the D8 Discover diffractometer. According to microprobe analysis, the Pd content in porpezite ranges from 0.73% to 12.83%, Ag does not exceed 2.75% and Cu reaches 3–4%. Considering the composition, such a gold–platinum mineral association from placers of the Anabar river is close to precious metals from placers of the Gulinsky massif, as well as Au–PGE ore occurrences related to ultramafic–mafic intrusions of other regions of the world. Complex gold–platinum-metal mineralizations are usually closely related to parent rocks and are often observed in sulfide and chromite ores of layered ultramafic–mafic intrusions with complex metasomatic and hydrothermal transformations. It is shown that in such cases gold and platinum form a magmatogenic paragenesis of minerals that coexist until the separation of hydrothermal solutions from magma, which, as a rule, transports Au and Ag with a small fraction of PGE from the fluid-ore-magmatic system in accordance with the model of the formation of gold–porphyry deposits. Within the Anabar diamond-bearing region, according to modern geophysical data, a significant number of local gravimagnetic anomalies associated with the presence of intrusive massifs of basic and alkaline-ultrabasic rocks in the cover and within the basement have been identified. This allows us to assume that the buried parent rocks of the Anabar Au–Pt placers may be located in both the Precambrian and Phanerozoic strata.

CHARACTERIZATION AND CHEMICAL COMPOSITION OF SULFIDE ORES ORIGIN FROM WANGGAMETI VILLAGE, MATAWAI LAPAWU DISTRICT, EAST SUMBA REGENCY

Sulphide ore is one of the most abundant minerals in nature. Indonesia has a very diverse potential for minerals, ranging from iron ore, laterite iron ore, iron sand to iron sulphide ore. Sulphide ore is one of the minerals that has the potential to become the parent mineral for gold. One area that has sulfide ore is Wanggameti Village, Matawai Lapawu District, East Sumba Regency. This condition encourages research to be carried out with the aim of knowing the types of minerals in sulfide ores by XRD analysis and to identify the content of elements in sulfide ores by XRF analysis. The results showed that the results of XRD analysis of sulfide ore samples taken from Wanggameti Village, Matawai Lapawu District, East Sumba Regency contained minerals of the types Quartz (SiO2), Calsite (CaCO3), Corundum (Al2O3), Iron Aluminum Silicon (Fe3Al2Si3) and Muscovite 2M1 ( KAl2Si3AlO10(OH)2). And the results of the analysis of the content of elements in the sulfide ore with XRF is 36.6% Si; S 1.2%; K 5.0%; Ca 27.8%; Ti 1.98%; V 0.23%; Cr 0.09%; Mn 0.77%; Fe 19.3%; Ni 2.99%; Cu 0.43%; Zn 0.1%; Mo 2.8%; Ba 0.2%; Eu 0.2% and Re 0.3%.
 Keywords:sulfide ore, mineral type and chemical composition

The improvement of sparsity gravity inversion using an adaptive lanczos bidiagonalization method

Inversion of gravity data is one the important steps in the interpretation of practical data. The detection of sharp boundaries between anomalous bodies and host rocks is an interesting point in the geological frameworks. The gravity inversion with sparsity constraint is a useful method to recover block subsurface density distribution, which is efficiently used for the quantitative interpretation of gravity data. The reweighted regularized method is a useful method to solve the inverse problem. However, in this type, we must face the updating gravity forward matrix and large matrix operation. The application of Lanczos bidiagonalization method can reduce the size of data and matrix in the inversion to resolve the large scale inversion problem. However, a very important problem is not resolved, which is update of reweighted forward matrix and new Lanczos bidiagonalization matrix. Here, an adaptive Lanczos bidiagonalization method is studied to select the Lanczos bidiagonalization factor. And a new projected method with adaptive Lanczos bidiagonalization method is study to avoid the updating sparsity reweighted function. We calculate the reweighted forward matrix and Lanczos bidiagonalization matrix only one time, which can essentially reduce the computational complexity. The inversion results of synthetic data show that the new improved method is faster and better than common reweight regularized Lanczos bidiagonalization method to produce an acceptable solution for focusing inverse problem. The improvement of adaptive Lanczos bidiagonalization in sparsity gravity inversion is also tested on gravity data collected over the Mobrun massive sulfide ore body in Noranda, Quebec, Canada. The inversion results indicate a remarkable correlation with true structure of the ore body that is achieved from drilling data.

Sulfidic gold ore leaching by cysteine in the presence of Na2SO3

Cysteine (CSH: C3H7NO2S) was used to leach gold and silver from sulfidic gold ore with a grade of 29 g/t Au and 28 g/t Ag. <20% of the gold was enclosed in sulfides/silicates, and over 70% of the silver was Ag2O. The gold extracted by 0.5 M cysteine at 70 °C was 42% in 24 h. When leaching was conducted at an initial pH of 11.5, the leachate was very alkaline, pH 12.5–13.5, and likely caused the partial decomposition of the gold-bearing sulfides, improving Au extraction. The addition of 5:1–2:1 M ratio of cysteine: Na2SO3 significantly improved gold extraction to 71% - 90%, respectively. The sulfite most likely mediated the conversion of cystine (CSSC: C6H12N2O4S2) back to cysteine. Finally, the presence of pyrite, arsenopyrite, and carbonaceous matter in the ore did not significantly impact gold extraction under the current experimental conditions. This finding might change if the undesirable cysteine oxidation could be mitigated, allowing for a lower lixiviant dosage to be used for leaching tests.

Разработка укрупнённого адсорбера для переработки продуктивных растворов

Productive solutions obtained after leaching of ores have a complex composition, including a variety of non-ferrous and heavy metal cations. The method of extracting nickel from productive solutions after leaching of sulfide and lateritic ores is the most important process in hydrometallurgical processing. Sorption by ion-exchange resins is an alternative to existing technologies for nickel recovery from productive solutions. The ability to selectively extract nickel and regenerate makes polymeric ion-exchange resins one of the most popular sorbents in the modern world. The polymer resin sorption process avoids wastage of reagents, costly filtration, and poor nickel selectivity compared to other metal ions associated with solvent extraction processes. In order to conduct experimental studies of sorption using Amberlite IRC 748 polymer resin, it is necessary to calculate and design an adsorber. The objectives of the study include the determination of the geometric parameters of the adsorber, the parameters of the sorption/desorption process and the development of a process flow diagram. As a result of the research, an enlarged adsorber has been designed to extract nickel from the productive solution after bacterial-chemical oxidation of cobalt-copper-nickel sulfide ore, and a process flow diagram for the process of obtaining nickel salts from the productive solution has been developed. The volume of the adsorber, its height, diameter, diameter of the inlet fitting, the height of the sorbent layer, the required resin flow rate, and the duration of the process before regeneration are determined. To ensure the continuity of the process, taking into account the duration of bacterial-chemical oxidation, periodic regeneration of the sorbent, the number of adsorbers in a common installation is taken to be two. When the adsorption stage occurs in one of the apparatuses, the stage of regeneration and drying of the polymer resin proceeds in the other. The estimated sorption capacity of Amberlite IRC 748 resin was taken as 21.6 g of nickel per 0.1 kg of adsorbent. Resin desorption has been supposed to be carried out with a 10 % sulfuric acid solution, at a flow rate of 5 l/h.

Experimental Study on Efficient Recovery of High-Grade Sulfide Ore

A gold mine is a typical broken zone altered rock type gold deposit, with some high grade primary sulfide ore at 20~30m from the surface, and the ore grade is about 5g/t. To understand the nature of the ore, Performed the process mineralogy testing and analysis, The occurrence state of the gold mineral is very good, Most gold is bare gold, It is conducive to the enrichment and recovery; To determine the best selection process and parameters, Conducted experimental studies including Nelson reselection and flotation, Finally determined to adopt the Nielsen reselection-heavy tail flotation process, Au grade 42.15g/t, Au recovery rate of 48.92%; Reconcentration tailings after one rough selection, two sweeps, two selection, Au grade 38.26g/t, The grade of Au of tailings is 0.16g/t; The combined Au recovery rate of reselection + flotation was 97.39%, The concentrate quality and recovery indexes are all good, The benefits are considerable.

Studi pengaruh penggilingan kondisi kering dan basah terhadap kinetika dan karakteristik distribusi ukuran butir bijih sulfida kompleks galena sfalerit – Uji pendahuluan

Grinding is generally carried out in wet conditions, but issues regarding water conservation and high-water treatment costs encourage the application of grinding in dry conditions. Both produce products with certain characteristics that affect the success of the next process. Grinding of P100 6 mesh (3.36 mm) ore was performed using steel ball media with dry and wet grinding with 33.33% solids for 5, 10, 15, 20, 25, and 30 minutes. Particle size distribution of the grinding product was obtained from the wet sieving process and the -200 mesh (-75µm) ore particles were analyzed using a laser diffraction particle size analyzer. The Alyavdin grinding kinetics equation model was used to study the kinetics of ore grinding behavior and the particle size distribution and its characteristics consisting of uniformity index, size modulus and fractal dimension were studied using the logistic, Rosin-Rammler (RR) and Gates-Gaudin-Schuhmann (GGS) equation model. Equivalent particle size (EPS) and specific surface area (SSA) observations were carried out on the -200 mesh (-75µm) grinding product. Grinding in dry condition is more effective in reducing the size of complex galena-sphalerite sulphide ore, indicated by high grinding rate with the highest K value of 0,135/minute, high cummulative % undersize, low size modulus, high uniformity index, high fine particle and high SSA compared to wet grinding. Alyavdin's kinetics model can describe the grinding kinetics of galena sphalerite complex sulfide ore, while the particle size distribution follows the logistic equation model.

Recovery of non-ferrous metals from sulfide ores by the method of heap bioleaching on the example of Allarechensk technogenic deposit

On the example of the Allarechensk technogenic deposit ore, the heap bioleaching method feasibility for the copper-nickel ores processing and non-ferrous metals recovery was considered. The content of metals in the initial ore sample was following: nickel – 2.42 %, copper – 0.75 %. The ore grinded to a size of -5+3 mm was irrigated with a solution containing a strain of Acidithiobacillus ferrivorans. The S:L ratio was 4:1, the flow rate was 0.1 mL/min. In pregnant solutions, the pH and ORP values were controlled, and the concentrations of ferrous and ferric iron, copper, and nickel ions were also measured. The experiment duration was 330 days, 8.9 % nickel and 6.1 % copper were recovered. The pathways for the metals extraction from pregnant solutions, as well as the utilization of bioleaching residue were considered.

The electrochemical technology of gold extraction from sulfide ores

The electrochemical technology of gold extraction from sulfide ores

APPLICATION OF GROUND MAGNETIC METHOD FOR DELINEATION SUBSURFACE STRUCTURAL CONTROL ON SULPHIDE ORE DEPOSIT IN BENUE TROUGH; A CASE STUDY OF IKENYI IZZI

The sulphide ore mineralization occurrence in the area is structurally controlled. However, wrong structural delineation has led to some recorded mine failures and revenue loss faced by investors and government. Therefore, subsurface structural mapping is crucial for the successful and reliable delineation of sulphide ore enrichment zone within the area. To this effect ground magnetic method was used to appraise the structural elements associated with the sulphide mineralization in Ikenyi Izzi area, part of Southern Benue Trough. The total magnetic field intensity (TMI) was recorded, corrected, and separated into regional and residual magnetic fields. The TMI varies from 33259.7–33329.7nT with an average field value of 33299.4nT. Whereas residual susceptibility value ranges from -36.3–25.7nT with significant magnetic closures which correspond to the areas of low and high susceptibility values. Three dominant structural geometries was identified in the area; NE-SW&gt;NW-SE&gt;N-S with few E-W structures. The NE-SW and some N-S structures characterized areas of high magnetic anomaly closures and are associated with the regional trends of the igneous intrusive rocks, whereas NW-SE structures host the ore deposit (Trending ≥N300°) and dominantly associated with areas of low magnetic anomaly zones. The cross-cutting relationship of the NE-SW, N-S and NW-SE structures infers a close association of the intrusions and mineralization, which was validated by ground truthing. The residual susceptibility values of 1 to 10nT and ≥ 10nT were inferred as shale and intrusive rocks respectively. The implication of this study denotes that missing appropriate structural elements delineation could lead to abortive mines target.

Assessment of risks caused by mercury pollution in Azerbaijan

Mercury is one of the most toxic metals and is widely used in the environment. It is a heavy liquid metal, which contains extremely dangerous substances that pollute the atmosphere, water and food. Sources of mercury emissions – Mining and smelting of mercury-containing ores from sulphide ores, extraction of non-ferrous metals, gold from ore, bleaching of cellulose, chlorine, caustic, vinyl chloride, electrical equipment (lamps, various power sources), measuring and control devices (thermometer, pressure gauge), mercury-containing preparations, cement production, use of mercurycontaining pesticides, combustion of coal and fuel oil. Significant amounts of mercury are also released into the environment during waste incineration. The results of the inventory of mercury emissions in Azerbaijan are presented. There were analyzed all the main areas of national industry of Azerbaijan supposed to contain mercury, conducted quantitative assessments, and in some cases revealed their trends. One of the obligations in accordance with the requirements of the Minamata Convention is the assessment of the general effect of mercury on human health. Cadastre of mercury emissions in the environment "Mercury", prepared by the United Nations Environment Program (UNEP Chemicals). Methods of finding and calculating waste.

Bioprospecting for and the applications of halophilic acidophiles in bioleaching operations

The economic recovery of metals from sulfide ores has become a topic of increasing interest due to the escalating demand for critical minerals and the reducing grade of available ores. Bioleaching is the use of acidophilic iron and sulfur-oxidising microorganisms to facilitate the extraction of base metals from primary sulfide ores and tailings. One significant issue limiting the use of bioleaching is the availability of freshwater due to the sensitivity of these microbes to chloride. The use of saline tolerant acidophilic iron- and-sulfur oxidising microorganisms will go a long way to addressing this issue. There are three possible means of sourcing suitable microorganisms; adaptation, genetic engineering and bioprospecting, with bioprospecting showing the greatest possibilities. Bioprospecting in search of native organisms for bioleaching operations has led researchers to numerous locations around the world and the isolation of iron- and sulfur-oxidising acidophiles that are capable of tolerating high levels of salinity has been of particular interest in these investigations.

A new potential natural chalcopyrite reference material for in situ copper isotope microanalysis

TQ-Ccp chalcopyrite with homogeneous Cu isotope compositions provides a potential reference material for in situ Cu isotope measurement.

Phase transformation in the metallic reduction process of low-grade laterite nickel ores for ferronickel alloy production

The utilization of low-grade laterite ores has become necessary due to the intensive mining of high-grade nickel sulphide ores for a long time. In this study, metallic reduction roasting followed by magnetic separation to produce ferronickel alloy and abandon gangue minerals provides an effectively treatment for laterite ores. The experimental results indicate that ferronickel alloy containing more than 7.5% Ni with its recovery of 95% and more than 70% Fe with its recovery of 90% was produced successfully from the low-grade laterite ore. In the metallic reduction roasting process, the thermodynamic analysis displayed that the higher temperature promotes the conversion percentage of the oxidic nickel and iron to metallic nickel and iron. The ferronickel particle morphology with a liquid-solid growth and aggregation mechanism in the reduced laterite ore were investigated by SEM/EDS. XRD analysis revealed that the nickel laterite ore was transformed from hortonolite (MgOx · FeO2-x · SiO2) to forsterite (MgOx · CaOy · SiO2) during the metallic reduction process.

Study of the effects of roasting and sodium thiosulfate on the extraction of silver from Volcanic Massive Sulfide ore

The main objectives of this article were to firstly decrease the amount of sulfide in the (Volcanic Massive Sulfide –VMS) in the eastern Sudan (Ariab) area through a roasting pretreatment, secondly determine the best and optimum (thiosulfate concentration – ammonia concentration – copper sulfate concentration - leaching time – pH) for extracting silver sulfide metal (Ag2S) also known as argentite from the same ore, thirdly using sodium cyanide concentration equal to the optimum thiosulfate concentration obtained from the experiments to determine which solvent is better at the same concentrations thiosulfate or cyanide.The leaching process took place at different concentrations, times, following a roasting pre-treatment at (300–400-500–600-700 °C), The Analytics of (ICP) and (XRF) showed that silver concentration is (10.91 PPM), iron is (15.76 PPM) and copper is (119.16 PPM), and the (SEM) analysis showed that Sulfur is present in the proportion of (26 %) in the ore, and from the study of fractions it became clear that the highest presence of silver was at the size (-106 + 75) micron.It was found that the best roasting temperature was (700 °C), and the best extraction using sodium thiosulfate was (61.06 %) at thiosulfate concentration (0.2 M) and ammonia concentration (0.2 M), time (6) hours, copper sulfate concentration (0.05 M), pH (10) and pulp density (25 %) at room temperature. As for sodium cyanide at the same concentration (0.2 M), it was found that the extraction was (49.47 %) at time (6) hours, pH (10), and pulp density (25 %). At room temperature, it was clear that cyanide was less efficient at (0.2 M) concentration than thiosulfate in dissolving silver.

X-ray absorption spectroscopic study of Pd2+ on Ni site in pentlandite

Abstract Norilsk sulfide ores are one of the largest known sources of Pd on Earth. Palladium in these ores is presented in platinum-group minerals (PGM) and base metal sulfides (BMS), especially in pentlandite [(Fe,Ni)9S8]. Although several studies demonstrated high concentrations along with heterogeneous distribution of Pd in pentlandites from Norilsk, the form of Pd in pentlandite has not been established. Here, we provide the first evidence for Pd incorporation in the structure of pentlandite from Norilsk ores using X-ray absorption near edge structure (XANES) spectroscopy, synchrotron-based micro-X-ray fluorescence (μXRF), and electron backscatter diffraction (EBSD). We present the first ever measured XANES spectra of Pd in pentlandite and atokite [(Pd,Pt)3Sn] as well as in other common Pd minerals. Divalent Pd in pentlandite was detected by XANES. The Pd spectra in pentlandite show no similarities with Pd spectra in PGM, metallic Pd, PdS, PdCl2, and PdSO4 which signifies that Pd incorporates into the lattice of pentlandite. Substitution of Ni by Pd in the lattice of pentlandite is supported by negative correlations shown by μXRF and electron probe microanalysis (EPMA) and complies with the previous studies. The additional EBSD study demonstrates a resemblance in cell parameters of the Pd-rich and Pd-poor parts of the pentlandite grains and reflects that Pd incorporation into the pentlandite structure does not imply any notable structure distortion. The combination of analytical techniques used in the present study demonstrates the great potential of these methods for understanding the mechanisms of noble metal incorporation into ore minerals.

Mineralogical characteristics of sulfuric acid formation during bacterial oxidation of flotation concentrate

The article presents the results of a study on the formation of sulfuric acid in the process of bacterial oxidation of sulfide ore flotation concentrate. The results are estimated from the point of view of the thermodynamics of the course of some bacterial oxidation reactions, calculating the standard enthalpies of formation - (ΔН0298), entropy (ΔS0298) and Gibbs energy of formation (ΔG0298) of some reactions and substances at 298 K. Conclusions about the formation of sulfuric acid based on X-ray phase and electron scanning microscope results of changes in mineralogical and elemental composition in the processes of bacterial oxidation of flotation concentrate are substantiated.