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By Nicol S. K, Firth B. A

Much effort over the years has been put into the task of devising parameters which adequately assess the metallurgical efficiency of mineral processmg operations. One of the most celebrated of these methods is the so-called "release analysis" method of Dell (1953) which tackles the problem in terms of an ideal separation based on sequential retreatment of the products and tails of a given separation process. Other methods have also been proposed by Jowett (1969) and by Holland-Batt (1971 ). While these procedures are appropriate to multi-component mineralogical separations, they perhaps do not lend themselves to the much more simple two-component systems encountered in coal preparation. However Dell (1962) has suggested the use of the term "specific profit" in coal preparation in order to assess the conditions that give maximum economic gain. Specific profit is derived from data relating washability data with equipment performance and operating costs. The procedure for using this criterion for comparative purposes is therefore somewhat cumbersome as is illustrated by its lack of widespread acceptance in the coal preparation literature.In contrast, an efficiency index, E, which is both simple and meaningful from the utilitarian standpoint, has been proposed by Tsiperovich and Evtushenko (1959a). This index is defined by the relation, E = Yield X Tailings ash/Product ash (1) A cursory examination of this parameter shows that it increases when yield and tailings ash increase and also when product ash decreases; all of which are desirable circumstances in coal cleaning operations.Further, it will be shown that slight variations in operation are amplified by this function which makes comparisons simple and direct.While the use of this index is quite extensive in the Soviet coal preparation literature for some reason it has not received wide usag~ elsewhere.

Jan 1, 1978

By S K. Michelic, M Schickbichler, A Kharicha, E Karimi-Sibaki

The requirements for the controllability of metallurgical processes are increasingly becoming the focus of both industry and research. Advances in this field of research not only impact the stability of processes but often also influence the quality of the final product. One important way to examine processes in-depth, and thus show potential for improvement, is to describe them using physicsdriven models. In metallurgy, thermodynamic and kinetic descriptions of interactions between individual components of a system are often used to describe and analyse important metallurgical phenomena across the entire process. However, for the creation of physics-based models, boundary conditions and process variables must be implemented to enable a description that is as realistic as possible. The collection and generalisation of boundary conditions and process variables is, therefore, an important step towards functional models. The focus of this study is the determination of mass transfer coefficients between all components in a steel/slag/refractory system. For this purpose, experimental and theoretical methods are applied. Laboratory scale experiments are carried out in an induction furnace, and the mass transfer coefficients of the defined steel/slag/refractory system are calculated from changes in the chemical composition of the various components. Additionally, a calculation of the mass transfer coefficients based on dimensionless quantities is carried out. By comparing the values of the mass transfer coefficients determined theoretically and those determined experimentally in the trials, the suitability of the calculation is examined. The collection of mass transfer coefficients provides essential findings for future kinetic descriptions of inclusion modification based on the effective equilibrium reaction zone (EERZ) approach.

Aug 21, 2024

By A Vickerfält, J Huss, J Martinsson

The European Union has listed vanadium (V) as one of the critical raw materials for the transition to a future green society, as stated in the Critical Raw Material Act, written by Grohol and Veeh (2023). In the steelmaking industry based on V-containing iron ore, V is a possible by-product from the slag. A requirement for slags to be suitable for V extraction is a V content preferably above 8 wt per cent as V2O3 and a phosphorus (P) content below 0.1 wt per cent as P2O5. Hence, it is important to keep V in the slag phase while the P is moved to the metal phase during the steelmaking process.

Aug 21, 2024

By J Knoblauch, D, P J. J Strobos, C Foggo

The Sally Malay Project is located 120 km north of Halls Creek in the eastern Kimberley region. Since commissioning, ongoing improvements on the plant have resulted in recoveries now greatly exceeding the initial design targets. The continual optimisation endeavours of the Sally Malay metallurgy department included an automation project that was done in close collaboration with Mintek. In this team effort, several problem areas were addressed and the FloatStar advance control system was successfully commissioned to stabilise and optimise the flotation circuit. The remote location of the Kimberley Nickel Mines operation, fly-in, fly-out roster and the current mining boom makes the acquisition of experienced flotation staff difficult. The implementation of an automated flotation control system reduces this burden and contributes to the training of inexperienced staff. This paper illustrates not only the process control improvements achieved as a result of the installation of the FloatStarÖ advanced control system, but also how it has assisted operational personnel with their understanding of the process.

Jan 1, 2006

By R Berry, S G. Walters, J A. Hunt, D Collett

The texture of an ore type is fundamental in understanding the metallurgical behaviour of an ore. This study will show examples of how quantified textural attributes (mineral shape, grain size and mineral association) can be obtained from automated and scanning electron microscope (SEM)-based microscopy and utilised using advanced image processing techniques. Examples will be shown of integrating quantified and semi-quantified meso- and macro-scale textural attributes as well as how they relate to texture-based visual logging systems. The implications of texture for processing behaviours such as comminution, liberation and recovery will be discussed. This research is part of a major collaborative geometallurgical project undertaken at the Centre of Excellence in Ore Deposits (CODES, University of Tasmania) and the Julius Kruttschnitt Mineral Research Centre (JKMRC, University of Queensland). The authors wish to acknowledge financial support and permission to publish from the sponsors of the AMIRA P843 GEMIII project.

Jan 1, 2008

The purpose of this paper is to present a detailed account of the development of the Blasthole Diamond Drilling method of stoping now used at the property of Big Bell Mines Limited, in Western Australia.The ore body is one of the large low grade gold deposits of this State, being a continuous lens 1,850 ft. long and ranging in width from 15 ft. at the ends to 120 ft. at the widest part, the average width being 59 ft. It was first worked in 1913 by a local syndicate, and up to 1924, when operations ceased, 64,448 tons of 3.4 dwt. ore were mined from a shallow open cut. Between 1928 and 1932, 15 deep diamond drill holes were put down to test the ore body at vertical depths ranging from 100 to 700 ft. On the information gained from these drill holes, Premier Gold Mining Co. Ltd. began underground explQration. A level was driven at a depth of 253 ft. and crosscuts put out to the full width of the, orebody at intervals of 100 ft. along the strike, all ore broken being put through a sampling plant. On completion of this sampling,' Big Bell Mines Limited was formed as the operating company, and a plant with a capacity of 1,000 long tons per day was erected and mining and milling operations were commenced in 1937. Ore was first mined from glory hole stopes, 65 ft. long, separated by 35 ft. pillars, by benching using conventional steel with changes up to 20 ft., all broken ore being hauled to the main shaft on the...

Jan 1, 1948

WHEN mining and treatment first started at Broken Hill only oxidised ores were available. These ores were rich in silver and lead-the silver mainly existing as chloride and the lead as carbonate.Treatment processes aimed mainly at the recovery of silver, lead being regarded as a by-product, and its recovery, except in so far as it affected silver recovery, was of minor importance.The first ore mined was carted to Terowie and thence railed to Melbourne, being smelted by the Intercolonial Smelting and Refining Co., of Spotswood.The first parcel (50 tons) returned £7442, or £148 16s. per ton to the Broken Hill Proprietary Company.The second parcel of 1053 tons, smelted at the Day Dream smelter, returned 132,142 oz. of silver, but no record is available as to its lead content.These results obtained from two parcels showed that by smelting the ore a handsome profit could be obtained, and Mr. La Monte was engaged to erect two 30-ton Nevada water jacket blast furnaces on Block 13. These furnaces were placed in charge of Mr. P...

Jan 1, 1928

By S F. Wang, J J. Yin

Dust pollution poses a persistent challenge within mining processes, giving rise to a spectrum of concerns, including occupational diseases, mechanical degradation, diminished visibility, and the potential for dust explosion incidents. Existing dust detection and monitoring methodologies face limitations, including insufficient measurement accuracy and intricate processing procedures. Consequently, a comprehensive identification and evaluation system rooted in image processing technology is proposed to facilitate real-time measurements of dust pollution in mining worksites. The study primarily employs grey scale average and fractal dimensions to characterise particle features evident in collected dust images. As a result, the data processing platform can dynamically process data and present dust pollution conditions. Notably, this research integrates the monitoring and assessment of dust pollution with the systematic adjustment of mining parameters, ventilation parameters, and strategies for dust reduction. Through statistical analysis of dust concentration and particle size during mining processes, rock properties such as components and cuttability can inform mining parameters. This information, in turn, guides detailed excavation strategies, including cutterhead speeds, torque, and excavation speed. Similarly, analysing dust characteristics derived from images is a valuable resource for gaining deeper insights into the efficacy of implemented ventilation strategies. By harnessing vision-based information detailing dust concentration and distribution, a wealth of direct guidance becomes available for refining ventilation parameters. This encompasses crucial aspects such as the selection of appropriate ventilation systems tailored to the specific mining environment and the optimisation of operational conditions for ventilation fans. Additionally, the detailed information derived from the visual data allows for strategic decisions on factors like the spatial arrangement of ventilation outlets and the calibration of airflow rates. Moreover, precise choices for dust reduction measures and parameters can be made based on the prevailing dust conditions. Upon real-time monitoring of dust pollution using the proposed method, corresponding measures such as spraying and foaming can be promptly implemented. Crucial parameters, such as spray angles and volume, are integral to these application processes. In essence, the proposed method assumes a pivotal role in not only dust monitoring but also the formulation of preventative and control measures within mining processes.

Sep 1, 2024

By J C. de Vries

When times are tough in the mineral industry û as they have been for some time û typical responses by mining companies are to cut costs and/ or increase production. The latter is seen to spread fixed costs, thereby also reducing unit costs per tonne mined. However, most mineral deposits respond to increased production rates by lowering ore grades, so the reduction in cost per tonne of ore does not necessarily result in a reduced cost per unit of metal produced. The authorsÆ experience is that this process often leads to a mine plan that is a long way from optimal. Producing to the point where marginal cost equals marginal revenue may work well in a manufacturing operation, but it is not necessarily the best strategy for a mining company with a depleting resource. Variations in tonnage and grade with depth, ore reserve optimism and a variety of other factors conspire to produce variations in production rates and grade that often result in suboptimal outcomes and potential mine failure. Added to this is the focus of industry analysts and senior corporate management on such measures as unit costs and ounces in reserves. This is perceived to have the perverse effect of driving the share price down when strategies are adopted that actually improve the value of the mining operation, and vice versa! Many mine failures can be prevented by a close examination of the tonnage grade curve and an understanding of how margins, net cash flows and resulting business risk change with cut-off grades and rates of production. A few relatively simple analyses early in the evaluation of a project can demonstrate the tradeoffs between the main decision parameters, leading to right-sizing of the operation. Once major commitments to major capital items have been made, and reserves have been publicly reported, optimisation of the operation becomes much more difficult than if it had been done earlier. Such investigations can also identify the upside potential and downside risks associated with factors outside the companyÆs control. Many strategies that may enhance value in the good times significantly increase the downside risk in the bad times. What is often called risk analysis typically looks at superficial issues, and does not evaluate the major factors leading to the potential for financial disaster. This paper illustrates some of these major risks, and demonstrates how they may be fully evaluated so that corporate decision makers can make fully informed decisions that take account of the real risks.

Jan 1, 2003

By N Currey, G W. Wilson, P Ritchie

Kidston Gold Mine in Queensland, Australia has a 310 ha tailings impoundment that has undergone final closure rehabilitation. Kidston Gold Mine evaluated their closure options for this low acid generating tailings impoundment, and due to a lack of cover soils and the cost of importing material, the mine decided to investigate the possibility of direct vegetation onto the tailings impoundment surface. The mine subsequently embarked upon a well planned and detailed research program to determine the feasibility and sustainability of this closure option. The research program included vegetation trials, toxicology studies for metal uptake by vegetation, as well as a comprehensive closure water balance model for the tailings impoundment complex. This paper describes the results of the long-term closure water balance for the tailings impoundment complex for the pre-closure state of the impoundment, as well as predictions towards the impoundment performance once final rehabilitation of the tailings impoundment complex has been achieved. The water balance presented is unique in that it is founded on unsaturated flow principles and accounts in full the impacts of the surface flux boundary conditions. This novel approach enables the prediction of actual infiltration rates into the tailings impoundment surface, which in turn allows for the calculation of how much seepage will exit from the tailings dam toe drains.

Jan 1, 2003

By S-C Shim, H-R Lee, Y Kang, H Shin

Since iron oxide and silicon oxide are major gangue components in various types of ore, FeO-SiO2 base slag, ie fayalite slag, has been often encountered in pyrometallurgical processes of non-ferrous metals. During most matte production processes such as the smelting of Cu, Pb, and Ni, the FeOSiO2 based slag is inevitably formed and plays an important role in refining crude metal as well as engineering aspects. Recently, similar pyrometallurgical approaches have been attempted in the recovery of valuable metals (Ni, Co, Cr) from wasted secondary batteries. Thus, the viscosity of the FeO-SiO2 based slag has great significance in properly controlling smelting processes. However, when molten metal or matte does not coexist with the slag during the measurement, there has been a serious difficulty in maintaining Fe valance and consequently, the slag composition. In the present research, the viscosity of molten FeO-SiO2 slag was measured in 1573~1673 K using a rotational viscometer. In order to keep the state of iron oxides, the oxygen partial pressure was controlled using CO/CO2 gas mixture. The optimised ratio of CO/CO2 could be calculated using Fe/Fe2+ and Fe2+/Fe3+ equilibria at each temperature. The composition of the slag, particularly Fe valance, after the measurement was analysed with the aid of an inductively coupled plasma – optical emission spectroscopy (ICP-OES) and an automatic potentiometric titrator. The measurement showed that the FeO-SiO2 slag has considerably low viscosity values in the molten state, and it sharply increases as the temperature decreases. In spite of the careful oxygen partial pressure control, a part of Fe2+ was found to be oxidised to Fe3+, with a maximal case reaching about 20 per cent. The increase in viscosity of FeO-SiO2 at low temperatures can be attributed to the composition change due to an unavoidable Fe2+ oxidation. In addition, the relationship between the change in the viscosity and the liquidus temperature of FeO-SiO2 based slag was discussed to understand the composition dependence of viscosity.

Jun 19, 2024

By V Narayanaswamy

SustainabilityÆs imperative of economic development in tandem with social advancement and environmental protection is widely accepted, but much debate remains about the practical implications for the minerals processing technologies and practices for the future. Experience in other industry sectors however suggests that sustainability can be a value-adding framework for innovation in processing technologies, business models and management systems. This position paper explores how sustainability can drive innovation in minerals processing, by reviewing pertinent ideas and experiences gained in non-minerals sectors. Sustainable innovations can generally be broadly ranked from incremental to transformative, with each category having its own typical improvement potential, timescale and technological and operational challenges. This leads to a æmud mapÆ for sustainable innovation in minerals processing with three distinct tracks: eco-efficient operations; sustainable plant design and sustainable processing. Competing models for the sustainable innovation process through either forecasting or back-casting, have in common the strong reliance on vision, perspective and competency, which in turn highlights the importance of sustainability frameworks. Such sustainability frameworks provide normative goals and option elicitation prompts to assist with the analysis of current processes and scoping of more sustainable alternatives. A comparative analysis of five prominent environmental sustainability frameworks revealed three cross cutting sustainability themes that challenge current resource processing technologies and practices. These are: fate of materials (zero dissipation of materials); compatibility of materials and processes; and materials intensity of industrial products and processes. Although the sustainability concepts presented in this paper have not been extensively road tested in the minerals processing industry, there is ample evidence that recent initiatives in the Australian resource sector illustrate the applicability of the proposed framework. It is therefore argued that more in-depth assessment of sustainable innovation concepts would be a valuable contribution to the sustainable resource processing theory and practice.

Jan 1, 2004

In order to do the discharge estimation better, it is valuable to find out appropriate formulas for estimating discharge in various pits, based on accumulating data, summarizing discharge patterns applying optimum seeking method and principle, by seeking redical exponent with help of the method of exhaustion, as well as testing and making statistics, in accordance with the quality standards established by our practical experience.

Jan 1, 1988

In blasting large tonnages of ore or material, the economy of the operation 'depends mainly on the mine manager's judgment in placing the holes to the best possible advantage and in determining the most effective size of hole to suit the conditions and requirements.The placing of holes is often looked upon as a problem involving so many uncertain factors that the application of simple mathematics is impossible. The uncertain factors arise when dealing with strata of different character, in hardness toughness and resistance to shearing.A study of the practice at many mines where all types of strata from hard ore to relatively soft overburden, and even coal, is being mined, suggests that the problem is not as complex as generally believed. There is, without doubt, some uniformity in the amount of burden given to holes of equivalent dimensions, regardless of the material being mined. The reason is simple. With too great a burden hard rock will not break out and soft rock will "bull". The nature of the strata is taken care of by the strength, quantity and distribution of the explosive charge and, to some extent, the spacing of the holes.It is because burdens are uniform in all classes of strata met with in mining, that a formula can be used to design blast hole layouts.The formula introduced in this paper is empirical as it is based on prevailing practice. It has been tested and proved remarkably accurate against every example available to the writer. Many thousands of blast holes, at many different mines, are represented by the examples given in the attached tables; to give further examples would only mean, unnecessary repetition. At the Mount Morgan Mine...

Jan 1, 1952

Environmental leaching methods such as the toxicity characteristic leaching procedure (TCLP) test or the ASLP test are used to assess wastes including mining and mineral processing by-products. These tests were initially designed as regulatory tests simulating conditions in a co-disposal municipal landfill waste facility and do not allow leaching performance to be predicted in site specific scenarios. Further, the assumptions underlying these tests tend to define worst-case scenario leaching conditions for by-products from the mineral industry disposed of outside a co-disposal scenario.   Recently some characterisation leaching test methods have been issued as ISO/TS standards (ISO/TS 21268-3:2007 and ISO/TS 21268-4:2007) that aim to define the leaching performance of soil type wastes and to predict the leaching performance of these wastes over long time frames. In this preliminary work these standards are trialled for by-products from the mineral industry and the quality of information that can be obtained from them compared to TCLP/ASLP tests.   Where clear comparisons were possible, the TCLP/ASLP tests were typically found to extract a similar, or often greater, amount of component than (i) tests conducted at the same pH but without the acetate buffer or (ii) for test conditions aimed at simulating long-term leaching in an eluate defined by the waste type. While further work is required, the preliminary results indicated that the tests may provide reliable long-term estimates of leaching performance of wastes in soil types of variable pH and provide a suitable basis for long-term planning for optimal waste handling, treatment or even re-use.

Jun 1, 2010

CONTENTS.IntroductionAcknowledgementsDescription of MineVentilation of MineOrganisation of Fire Fighting SquadsTraining of Fire Fighting SquadsRescue WorkFire Fighting and Rescue EquipmentFire AlarmsConclusionINTRODUCTION.This paper should be read in conjunction with that by R. P. Hooper, entitled "Underground Mine Fire Prevention at the South Mine," Broken Hill. Contents of the paper have been arranged similarly for easy reference. The methods used in educating employees in the use of Proto apparatus remain basically the same, but many changes in the methods and equipment used in subjugating fires have been brought about by the practical experiences gained by officers of the company in extinguishing the outbreaks which occurred in the latter half of 1944.Three fires took place during this period, the first in July, on M.L. 11 in openings leading to timbered workings previously worked and subsequently abandoned by...

Jan 1, 1946

By P Duplancic and C R Lilley, R Hudson, D Beck

For deep block and panel caving mines, undercut or extraction level instability can have as much impact on overall recovery as underbreak or the premature ingress of waste. If the area of the mine affected by excessive convergence is small, recovery is usually possible. However, there are several examples of entire blocks that were abandoned prematurely due to footprint collapse. Clearly, such global instability has a major impact on recovery and must be avoided – this is one of the essential tasks for the design team.The design problem is complex. The planning engineer must ensure that the footprint has sufficient capacity to withstand the maturing loads in the cave, accounting for the effects of stress path, geological structures and the rock mass conditions. These are often uncertain and only sometimes quantified.The demand on the footprint will also be influenced by decisions and actions taken during production, especially related to draw, which can worsen a developing problem. Perhaps most importantly, the design decisions that favour stability and lead to lower deformation also negatively impact on idealised cave flow. Many engineers aim to minimise the size of extraction level pillars, to improve theoretical future resource recovery but in fact this can reduce recovery if widespread deformation ensues due to the undersized pillars.In 2014, PT Freeport Indonesia undertook detailed numerical analysis to quantify the effects of variability in rock mass conditions and geological structure on overall footprint performance. The analysis accounted for a range of stress paths and maturing cave loading scenarios sourced from a calibrated whole-of-cave deformation-flow model. The intent was to replicate some of the diversity and distribution of pillar deformation outcomes that may be seen in practice at Freeport.The discontinuum finite element analysis was able to replicate damage localisation around persistent structures, a realistic distribution of drive deformation and show how small areas of instability can evolve into major problems if poorly managed. The limits of pillar size and ground support as solutions to a number of different instability problems was also investigated, showing that pillar size alone was not a sufficient remedy for all adverse circumstances.In this paper, we describe the workflow for numerical analysis of footprint deformation. We discuss the compromises and considerations for balancing the sometimes competing needs for efficient extraction levels pillars, ground support and prudent draw strategy.CITATION:Beck, D, Hudson, R, Wilson, A D, Duplancic, P and Lilley, C R, 2016. An investigation of factors affecting the long-term reliability of extraction level pillars in deep block and panel caves, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 295–304 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By X Zhang, Y Zhu, P E. Ngoepe, P P. Mkhonto, W Xiong, L Han, L Lu

The triazine molecules have not been given much attention and they are potential collectors that may positively impact the mineral processing industry. The adsorption of triazine as collectors such as sodium 2,6-dithio-4-butylamino-1,3,5-triazine (SDTBAT) on pyrite form a basis in design of flotation collectors that may be applicable in a wide range of sulfide minerals. The SDTBAT collector was compared with the sodium normal butyl xanthate (SNBX) and sodium normal butyl dithiocarbamate (SNBDTC). All collectors were adsorbed in their neutral form containing sodium on the pyrite (100) surface. The computational calculations found that the adsorption energies followed the order: SDTBAT (-300.35 kJ/mol) > SNBX (-186.10 kJ/mol) > SNBDTC (-163.78 kJ/mol). It was observed that the SNBX and SNBDTC adsorbed through the S atoms, while the SDTBAT adsorbed through the S atoms and N atoms onto Fe atoms. It is clear that the SDTBAT had a strong binding energy which is attributed to the presence of the triazine group that is electron depositing to the active S atoms compared to the SNBX which possessed the oxygen that is electron withdrawing. Moreover, the SDTBAT collector was found to bind stronger than the xanthate. This was complimented by microflotation tests that showed fast floating and higher recoveries of pyrite when using the SDTBAT collector than the xanthate and DTC. This clearly demonstrated that the SDTBAT is a potential collector to replace the xanthate collector due to its high selectivity and flotation power.

Aug 24, 2022

By Marton A

The Readymix Group have a Quarry Improvement Program - 'Building in Quality (BIQ) which has many parallels to the ICI Explosives' total quality management - 'Quality Improvement Program' (QIP). Both companies have for some time recognised that the 'do it right first time' principle means less wasted effort and materials, that efficiency breeds profitability and so actively promote the quality culture. To install the principles and generate the culture requires considerable commitment and effort from the top down and invariably spreads to the suppliers and sub-contractors. Understanding the component processes involved with the quarry operation, analysis of those processes and gaining a breakdown of the cost of non conformance then allows the astute quarry operator to make the necessary changes to improve the process to realise profits. This paper outlines the steps in such a process and the profitable outcomes of the commitment to continuous improvement at the Nickol Bay Quarry.

Jan 1, 1994

Evaluation of the Iron Blast Furnace Process using Heat and Material Balances of the Flame-Zone

Sep 13, 2010