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By J Lea, D C. Kettlewell

The Carina iron ore deposit lies 105 km northeast of Southern Cross, WA. The area designated the Yilgarn Iron Ore Project (YIOP) is comprised of five prospects along an east-southeast trending greenstone belt that extends from the Helena-Aurora Ranges in the northwest to the Yendilberrin Hills in the southeast, over a strike length of approximately 40 km. The YIOP project encompasses the previously identified iron deposits of Bungalbin, Bungalbin East and Mt Walton. The Carina deposit was discovered by Polaris Metals NL in May 2007. The Carina deposit is located within and parallel to the structurally complex northwest trending Mount Dimer shear zone. The volcanosedimentary Archaean-aged greenstone sequence consists of ultramafic and mafic lavas and flows with interbedded sediments dominated by chert and banded iron formation (BIF). Supergene enrichment processes formed a goethite orebody replacement of BIF sequences within a doubly plunging synclinal fold structure. Mineralised outcrops dominated by goethite form a low ridge 1500 m long, up to 90 m wide and drilled to over 200 m in depth. In the vicinity of the Carina deposit, iron occurrences have been identified over at least a 12 km strike length and the exploration potential of the area is identified as 30 - 40 Mt. Polaris Metals began exploration in the area in 2006. Target generation in the area used existing state geological survey maps and regional magnetic survey data to focus on BIF occurrences associated with major structures. Early field investigations resulted in the identification of a large outcrop of predominantly goethite mineralisation at Carina. Detailed geological and structural mapping was completed, followed by close-spaced reverse circulation and diamond drilling. The mineralisation is predominantly goethite with specular and coarse platy haematite localised along structures that cut the goethite mineralisation. Mineralised zones are moderately vuggy and larger cavities occur in proximity to fault zones that transect the orebody. A capping by a thin veneer up to 9 m thick of canga or ferricrete occurs in places. By December 2008, 178 reverse circulation and 11 diamond drill holes (seven surface holes, four tails) were completed. The current JORC-compliant resource estimate is based on assays from 72 RC drill holes and using a 55 per cent Fe cut-off stands as an Inferred Resource of 27.9 Mt at 58.6 per cent Fe, 1.3 per cent Al2O3, 3.7 per cent SiO2, 0.09 per cent P, and 10.1 per cent LOI. Assaying has recently been completed and will be incorporated into a new updated resource later in 2009.

Jan 1, 2009

By B Klein

This paper stems from research and development in sensor and sorting technologies towards future sustainable mining undertaken by the UBC Mine-Mill Integration group in collaboration with MineSense Ltd. Sensors and sensor-based technologies such as ore telemetry and sorting are envisioned to be a significant component in achieving such ‘invisible’ future sustainable mining. Such technologies offer high flexibility and power in use: delivering valuable information from the very preliminary stages of mining exploration through to final upgrading of the ore preceding the fine comminution stages. This paper reviews sensors and sorting as enabling technologies towards a future smart mining operation and introduces a model in which sensor-based exploration (down-the-hole sensing), ore exploitation (smart-shovels), transportation (smart-conveyors) and preconcentration (sensor-based sorters) are effectively integrated to increase the present value of operations. It is anticipated on the basis of several case studies that an effective use of sensor technologies through tomorrow’s ‘smart mine model’ should lead to several positive impacts ranging from increased mining production, to reductions in transport costs, overall energy use and waste generation. In this way sensors can be used to maximise the profitability and present value of the mining operation from the exploration stage through to mine closure.

Nov 22, 2011

By P J. Howard

Atlas Iron Limited’s McCamey’s North project lies at the eastern end of the Hamersley Basin, approximately 50 km east of Newman, Western Australia, and 3 km northeast of BHP Billiton’s Jimblebar Mine. The presence of significant surface iron mineralisation identified during field reconnaissance, has subsequently been further defined by detailed mapping and RC drilling.The project area is dominated by outcrops of moderate to steeply north and south dipping banded iron formation, cherts and shales of the Boolgeeda Iron Formation overlying rhyolites and rhyodacites of the Woongarra Volcanics. In lower lying areas recent colluvium and alluvium mask the Archaean geology. Drilling and downhole geophysics has allowed a composite stratigraphic section to be compiled through almost the entire Boolgeeda Iron Formation.Surface orientations and subsurface stratigraphic correlations using natural gamma logs indicate large scale open folding about east-west trending fold axes across the project area; while small scale tight to isoclinal folding with similar fold axis orientations are visible at the outcrop scale. These folds are cut by a number of moderate to steeply south-dipping normal faults defining a series of north-dipping fault blocks which repeat the stratigraphy across the project area.Bedded iron mineralisation consists mainly of haematite-martite and goethite ores with best results of 78 m @ 60.5 per cent Fe. Vitreous goethite is observed at the surface of the mineralised horizons. The mineralisation exhibits a strong stratigraphic control and extend down-dip up to 120 m below surface. The strike extent of the mineralisation is still to be determined. An inferred resource of 39 Mt at 58 per cent Fe has been defi ned to date (ASX: AGO 3 February 2011).The fi ndings at McCamey’s North indicate that there is potential for economic iron mineralisation to exist in other areas of Boolgeeda Iron Formation within the Hamersley Basin.

Jul 11, 2011

By N McIntyre, M Edraki, K R. Jain

From the very early stages of a mining project, there is a requirement to predict the chemistry of potential drainages from various waste storage facilities. However, using relative masses to scale chemical loads measured by laboratory kinetic tests, such as humidity cells, to a full-scale mine waste facility will lead to concentration predictions that are unrealistically high for many dissolved constituents. Scaling factors developed by various procedures indicate that laboratory rates may range anywhere from two to eight times (Drever and Clow, 1995) to 100 to 1000 times faster than field rates (Malmstrom et al, 2000; Smith and Beckie, 2003; Ritchie, 1994). This contribution will use previous works and secondary data to discuss the significance of scale in water quality predictions. It will also present primary experimental geochemical and numerical data from a column leaching study on coal spoils to discuss potential applications of mesoscale leaching tests in bridging the gap between bench-top tests and field scale trials.

Aug 2, 2023

By T Niitti, J Turunen, P B, A Rinne

In todayÆs marketplace, with high metals prices, many operations are faced with the challenge of improving recovery in the particle size ranges which are normally difficult to recover. This presentation focuses on the various methods used to alter the flow dynamics in a mechanical flotation cell, thereby improving metallurgical results. Modern computational fluid dynamics (CFD) tools have been used in the design phase, with subsequent validation at the plant. Some of the validated variables include mixing profile, power draw and local air hold-up. This presentation underlines how modern CFD analysis can be used to screen and select different approaches before commencing costly trial-and-error experiments at plant scale. Two methods of affecting flow dynamics are discussed û firstly, by altering the geometry of the rotor-stator area and, secondly, by fitting additional features in the tank. The rotor-stator area can be modified to provide more concentrated turbulent kinetic energy or, respectively, to provide more pumping efficiency with less attrition. The tank can be fitted with various additional features, aimed to create different particle suspension profiles. The benefit of both methods is that they can be applied not only to newly installed flotation technology, but also to existing plant cells, thus enabling potential improvement in the mixing profiles, solids suspension, tank sanding and metallurgical performance. Results of several sitesÆ tests are discussed in terms of flow variables measurement as well as metallurgy. This paper demonstrates the effects of different flow dynamics on the mixing profiles and metallurgical results of existing mechanical flotation cells.

Jan 1, 2006

By Kametani H

Since pyrite is a semiconductor, the relationship between the leaching rate and the semiconducting properties is of interest. In order to investigate this relationship, a pyrite concentrate (95% FeS2) was oxidized at 90¦C (363 K) in an acid solution containing 100 g/dm3 H2SO4 and 1.0 to 25.1 g/dm3 total Fe. The suspension potential (Pt vs. SCE) was maintained at the desired values, within the range 0.40 to 0.70 V, by controlled additions of a KMn04 solution during leaching. The results were analyzed using a simplified kinetic expression. The rate constant was independent of the Fe concentration, while it increased with suspension potential. Partly oxidized samples were then prepared at varying fractions of reaction. After removing the elemental sulphur formed, they underwent thermoelectric power measurements using a packed bed lying in a temperature gradient. The value of thermo- electric power increased from about 0 to 30 pV/K in the early stages of oxidation. The results obtained are compared with those for chalco- pyrite reported in a previous paper.

Jan 1, 1987

By S H. Burgmans, B Anderson

This paper aims to define the specific challenges relating to dredging fine tailings from an above ground storage facility for transferral to a mined-out pit. In addition, it compares dredging and mining perspectives on dredging of fine tailings.

Jul 1, 2021

By Denholm W. T, Rankin W. J

The reduction of zinc from lead blast furnace slags using hydrogen was studied at 1300¦C as part of a laboratory investigation of zinc fuming. To perform the experiments, 300 g "spent slag" was melted in a crucible. Hydrogen was then injected into the slag through a lance and fresh blast furnace slag was added regularly in small quantities over a period of 40 minutes. Zinc added in the fresh slag was reduced and the zinc level of the bulk slag attained a steady state value of between 1 and 9% after about 10 minutes, depending on the gas injection rate. Because of the high reactivity of hydrogen, bulk supply of hydrogen to the slag was the rate limiting step at the flow rates used and it is believed that the gas-slag reactions in the system were at equilibrium. A partially/stabilized zirconia cell with a Ni/NiO reference electrode was immersed in the slags during the experiments and the steady/state oxygen potentials of the slags were measured. By using the experimental oxygen potential values and calculated values of the steady state concentrations of zinc in the offgas, the activity of ZnO in the slags was calculated from the Gibbs's free energy change for the reaction:

Jan 1, 1989

By D Tucker, K Harney

Hatch forecasts that an increasing share of seaborne traded iron ore will be ultrafine, being either concentrate or pellet feed. This provides several challenges for the iron and steel industries, but the principal concern is: how much ultrafine iron ore can be consumed on sinter strands and with a minimal effect on productivity?This paper will identify new supply by project through 2020. Demand will be estimated for sinter production and practical steps will be identified to increase ultrafine consumption in sinter strands. The long-term iron ore price will be forecast to balance supply and demand. The paper will conclude by assessing how the pricing of ultrafine ore will develop relative to the Chinese iron ore indices.CITATION:Tucker, D and Harney, K, 2015. Iron ore ultrafines challenges and opportunities, in Proceedings Iron Ore 2015, pp 501–504 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By N Pirouznia, F Rashidi Nejad, S Naraghi

Sungun Copper Mine, which is the second largest copper mining operation in Iran has a large tailings storage facility with a seepage control dam located downstream of the main dam. Surface and groundwater in surrounding area of the tailings storage facility has been monitored for ten years. This paper will discuss the results of the surface and groundwater monitoring and seepage control at the Sungun Copper Mine. The results of the study show that if the tailings storage facility influence the water quality of the rivers, this effect is not significant, so that the prevailing parameters of the measured parameters were within the permissible standard of drinking water in Iran.CITATION:Rashidi Nejad, F, Naraghi, S and Pirouznia, N, 2018. Surface and groundwater monitoring and seepage control at the Sungun Copper Mine, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 439–453 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By M S. Cassola

It’s expected that the world economy will face a stable and continuous growth in the demand of iron ore, reaching more than two billion tonnes per year within the next year. After decades exploiting resources with high content of iron ore, now the industry faces the challenge to exploit and beneficiate more complex ores.According to the industrial practice, the flotation technology is one of the most important and effective beneficiation processes to deal with low-grade iron ores around the world. However, even with this, it is still necessary to search for new processing routes or promote the optimisation of the existing circuits.The broad application of this technology is an outcome that deeply relies on the proper selection of flotation chemicals specifi cally designed for each system. New collectors are in continuous development as flotation performance significantly relies upon their optimisation.The reverse iron ore flotation in Brazil, mainly constituted by haematite and quartz, uses ether amines as collector for silica minerals and caustic corn starch as depressor for haematite. The process selectivity is highly impacted by the features of the etheramine, such as:• mono or di-etheramine,• neutralisation degree,• chain length,• branched or linear chain,• the flotation pH, and• the size distribution of the flotation feed.This paper describes the experience obtained from laboratory and industrial trials on different ores, conducted to improve the selectivity and recovery in the reverse iron ore flotation by selecting the required collector for low-grade ores.

Jul 11, 2011

By J Kinal, I Mitchell

Many flotation plants use pH to adjust the pulp chemistry of their system to achieve optimum separation. For example, in a sequential lead/zinc circuit the pH during sphalerite flotation is increased to 10.5 or greater to depress galena and pyrite, thereby improving selectivity for sphalerite. However, maintaining a pulp at a particular pH value does not necessarily provide the operator with an abundance of information regarding the chemistry changes occurring within a plant. This paper provides the reader with a number of pulp chemical observations in several plants, showing that the same trends are noted over time; however, the magnitude of the measured values do change. Further, the changes in magnitude are invariably associated with a change in mineralogy. Thus, is measuring pH enough? Can the Eh, dissolved oxygen and temperature be measured at the industrial scale reliably? And, are these measurements useful?

Jan 1, 2006

By S Farrokhpay, C Akop

Copper-gold-pyrite ore types with an elevated pyrite head grade utilise a sequential flotation circuit to recover initially a copper-gold concentrate with a pyrite-gold concentrate being produced from the tailing of the initial circuit.A simpler flotation circuit with lower operating and capital costs for treatment of such copper-gold-pyrite ores with an elevated pyrite head assay was sought in the described work. After characterising the ore, the objective was to apply bulk rougher flotation of both the copper minerals and pyrite for the copper-gold-pyrite ore at natural pH. Hence, no lime or other pyrite depressants were required in bulk roughing. The bulk rougher concentrate was upgraded in a cleaner circuit to reject non-sulfide gangue and then the resulting sulfide concentrate was separated by depressing the pyrite to produce two products (copper and pyrite concentrates, both having significant gold assays). A standard test with a sequential circuit was applied to the same ore for comparison.The chalcopyrite and pyrite losses in the tailing from the rougher circuit were the same for both bulk and sequential roughing (less than six per cent). In cleaning (bulk circuit), the effective pH for pyrite depression was 11.8–11.9; copper recovery was 70–75 per cent (grade of 15–20 per cent copper) and the sulfur recovery (pyrite product) was 80–85 per cent (grade of 34–36 per cent sulfur).These results approached those for the sequential circuit where copper recovery was 80–85 per cent (grade of 15–20 per cent copper) and the sulfur recovery (pyrite product) was 83 per cent (grade of 38 per cent sulfur).The observed effects of feed sizing on the liberation of minerals in the rougher feed are discussed. Options for improving the bulk circuit results are also considered. Importantly, the implications of various aspects of these findings for the bulk circuit are discussed with an industrial focus.CITATION:Akop, C, Farrokhpay, S and Johnson, N W, 2014. An alternative circuit for chalcopyrite-pyrite ores with elevated pyrite content in Cu-Au ore treatment, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 407–416 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By O Joneydi, J Viljoen, R Funnell

Computational Fluid Dynamics (CFD) modelling is a useful tool that can assist engineers in designing effective ventilation systems for the control of airborne dust generated during mining operations. Thistechnology can save time, effort and the costs associated with re-work or the traditional on-site experimental field trials by running desktop 3D simulations of the various proposed scenarios using state-of-the-art CFD analysis tools. Before implementing a dust management system, an understanding of the behaviour of airborne dust particles in the face zone can be achieved, which can improve the confidence in the secondary ventilation and dust management design. Usingadvanced numerical models, suitable dust extraction strategies can be foreseen, and multiple scenarios can be simulated and investigated quickly. As a case study, dry drilling operations in Kimberlite orebodies produce large quantities of fine dust which poses health and safety risks. An effective dust management system is required to achieve acceptable face conditions. A possible practical solution is a ducted exhaust ventilation system with a force fan in the face zone. This paper demonstrates how CFD analysis can be used as a tool to assist the design engineer with validating and optimising the proposed ventilation design by tracking the trajectories of different size dust particles, to determine the best equipment layout and appropriate flow rates which minimises airborne dust.

Oct 12, 2022

By W N. Qin, B Zhang, W Z. Huang, X S Mo

Mengzi Mining and Metallurgy Co, Ltd (MMMC) polymetallic ore contains recoverable amounts of tin, lead, zinc, pyrite and other valuable minerals. With the change in orebody, the run-of-mine (ROM) ore changed from lead zinc rich ore to tin rich ore, where the current ROM ore contains 0.45–1.25 per cent tin, 20–25 per cent sulfur, and 0.20–0.35 per cent copper. The previous processing flow sheet was designed to recover lead zinc rich ore and it is clearly not suitable for recovery of the current tin rich ore, where the tin was already overground and tin recovery was only 50.19 per cent. The Mengzi Mining Company has recently modified the concentrator circuit by incorporating rod mill and high efficient Derrick fine screen. As a result of the improved classification efficiency, the overgrinding of the tin ore was minimised and the recovery of tin was improved by 20.71 per cent, ie from 50.19–70.90 per cent. An additional $10 M revenue per annum can be achieved as a result of the modification.CITATION:Qin, W N, Huang, W Z, Mo, X S, Zhang, B and Wheeler, J, 2014. Application of high efficient fine screen to improve the recovery of tin concentrate, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 487–492 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By E K. Chiw, S-M Jung, S M. Masuka, ika

The world reserves of high-grade iron ore have depleted necessitating the need to utilise any existing natural iron ore deposits to meet the demands of the world’s expanding economy using hydrogen in the reduction process to curb CO2 emission. These low-grade ores include iron ores with high phosphorus content. The thermodynamic conditions in the blast furnace allow for the reduction of phosphorus that readily dissolves into the molten iron. Phosphorus in the gaseous state readily dissolves into the molten iron and therefore must be removed due to its negative influence on the mechanical properties of steel. The removal of phosphorus from molten iron is difficult causing the phosphorus to concentrate in metallic iron. The aim of this study is to provide basic knowledge on the phosphorus distribution after reduction using the CO-H2 and possibly provide the optimum conditions for phosphorus partitioning into slag, increasing the probability of its removal by magnetic separation. Total porosity, pore size distribution and surface area of the pellets used were measured using a mercury pressure porosimeter. The reduction was carried out using thermogravimetric analyses (TGA). The reduction rate increased with increasing H2 and was highest when 100 per cent H2 was used. Metal elements distribution in the reduced pellet was clarified using electron probe microanalysis (EPMA) and showed that phosphorus was distributed in the same areas as Ca. More phosphorus was concentrated in slag when 50 per cent CO–50 per cent H2 was used, increasing the probability of dephosphorization using magnetic separation. The concentration of phosphorus into slag was related to the rate of reduction. Further investigations into the reduction kinetics of this ore by CO-H2 is suggested to validate these findings. Nevertheless, a comprehensive thermodynamic analysis of the reduction of phosphorus containing phases found in iron ore with carbon, CO and H2 was provided to assist in selecting the optimal reduction experimental conditions.

Sep 18, 2023

By D Brereton, C J. Moran

In this era of rising focus on the social and environmental costs and benefits of mining operations, the valuation methodologies used to assess such impacts become increasingly important. Within an industry dominated by an engineering culture that places emphasis on net present value (NPV) calculations using high discount rates, difficulties often arise when attempting to justify projects with longer-term, harder to quantify benefits. This is particularly so when these benefits fall in the social and environmental domains and involve other stakeholders. In this paper, we summarise the results of a recent literature review on this subject, which focused on the valuation of æBeyond ComplianceÆ initiatives in the mining sector. We discuss a range of approaches including the quantification of hidden internal costs, financial methods of incorporating risk into calculations, the integration of quantitative and qualitative information, and also the valuation of æexternalitiesÆ or costs and benefits borne by others. We then use a series of examples relating to the management of water in the minerals industry to illustrate how some of these approaches could be applied. There are high-level commitments from both individual companies and groups such as the ICMM to incorporate sustainable development criteria into decision-making processes within the industry. We conclude the paper by arguing that, to meet these commitments, there is a need for the industry to adopt a broader range of valuation methodologies than appears to be the case at present.

Jan 1, 2006

By G J. I dos Santos

The risk assessment of mining projects is directly related to the possible failure in estimating, and as estimates are made from sampling results, this activity should be done in a judicious and planned manner, to avoid surprises at the start of project operation. Pierre Gy’s (1995) sampling theory addresses the issue of sample representativeness and indicates that only the certainty that the sampling procedure was performed with quality may result in samples being recognised as representative. To validate the representativeness of samples from sampling boreholes selected for studies of mineral processing, the team of geology resource assessment of VALE has proposed a methodology based on the use of statistical analysis tools, which in addition to considering the spatial distribution of these samples in deposit, considers whether they are representative of the populations studied, allowing the geologist to make a quick analysis of sample representativeness.

Jul 11, 2011

By L Gobbo

X-ray diffraction (XRD) provides useful information about the composition of an ore sample in terms of quantification of crystalline phases and amorphous content. The use of new, fast detection systems implemented in CubiX FAST industrial diffractometers creates the opportunity to use this technique in exploration and modern process control. Besides the chemical composition of iron ores, their phase composition is also an important factor for exploration, quality control and processing. In the analysis of iron ore, XRD can identify the phases containing iron, such as haematite Fe2O3, magnetite Fe3O4, and goethite FeO(OH), and any other mineral phases present, especially silicas. Quantitative analysis is possible by various classical methods such as straight line or polynomial calibration with standards, but modern quantification analysis techniques such as Rietveld analysis or full pattern autoscale analysis are attractive alternatives, as they do not require any standards. These methods offer impressive accuracy and speed of analysis. Another analysis technique offering great benefit to ore exploration and process control is cluster analysis. This technique greatly simplifies the analysis of a large amount of data, eg from drill core samplings, and automatically sorts closely related scans of an experiment into separate clusters and marks the most representative scan of each cluster as well as outlying patterns. This can facilitate multi-dimensional compositional mapping of ore deposits, identifying regions of favourable mineral composition and allows fast and reliable tracking of the process. It is the most economic procedure to have automatic data evaluation without involving any dedicated personnel in the process. Details of the techniques used, sample optimisation methodologies, results, data precision and limitations will be discussed. The approaches have enormous potential as an inexpensive, reliable tool, useful in the characterisation of iron ore materials in an industrial environment.

Jan 1, 2009

By Robinson T

The paper describes a spreadsheet system that enables selection of projects and companies that meet the user's corporate exploration and/or acquisition philosophy. A regularly maintained commercially available database has been used as the basis for this system. It provides an easily accessible efficient com- prehensive search method. The technique enables ranking by various criteria, both technical and financial, to provide groups of projects/companies that are of interest. Initially, target size parameters such as reserves, production and mine life are applied together with geological criteria such as age and deposit type; the significance of the targets in the context of the Australian gold industry is addressed.

Jan 1, 1988