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By S Joyce, Z Agioutantis, D van Zyl, D Shields

Over the past 15 years, the mining industry has begun to incorporate the concepts of sustainable development and sustainable mining practice across the life cycle of mineral operations. This requires addressing economic issues, community impacts and concerns and environmental protection, and is captured in part by the phrase ‘design for sustainability’ (McClellan et al, 2009). Over the same period, the industry has seen a gradual decline in ore grades for many mineral commodities. As a result, large volumes of tailings and mine waste rock are being produced around the world, and it is expected that the annual production volumes of these materials will increase, even if there is not a significant change in the demand for materials.Another related thread of change has been the realisation that societies need to move away from linear economies (raw materials, production, consumption, disposal) towards more circular ones. This will help societies become more resource efficient, which is defined by the United Nations Environment Programme as reducing the total environmental impact of the production and consumption of goods and services, from raw material extraction to final use and disposal. The goal is to create more with less and deliver greater value with less input. Circular economies require thinking in terms of the waste hierarchy (reduce, reuse, repurpose, recycle, recover, landfill).The challenge is that the waste hierarchy was originally designed to address embodied mineral content in products rather than mine waste and tailings generation. It will need to be reconsidered in a mine life cycle context, focusing on a value-based conception of waste (Van Ewijk and Stegemann, in press).In parallel to these changes, it has remained an imperative in the mining industry to dispose of these waste materials as economically as possible while protecting the environment. Single handling of these materials has been the main target, which reduces the life cycle costs of their management but may make reuse of waste and tailings technically more difficult or economically infeasible.This presentation explores a rethinking of the large volume earthen material waste issue at mines. The underlying theme is that some or all of these materials can be valuable resources for the future that can positively contribute to sustainable development. These resources can offer economic gains to firms, communities and societies; contribute to environmental well-being; enhance social interactions with the previously mined landscape if handled properly; and, with proper policies in place, reduce governance commitments. Each of these topics will be briefly explored. This will be followed by a discussion of approaches to manage design and operations to allow future resource recovery.CITATION:Van Zyl, D, Shields, D, Agioutantis, Z and Joyce, S, 2015. Waste not, want not – rethinking the tailings and mine waste issue, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 7–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By Hewitt D

A study of two laterite profiles developed on a serpentinite near Rockhampton, shows that loss of Si02 and MgO results in the relative concentration of Fe203, A1203 and a number of minor elements. Serpentine is broken down to form montmorillonite, goethite, quartz and kaolinite. Enrichment of nickel occurs, and it is shown that the element is mainly associated with montmorillonite and serpentine. Highest nickel values are associated with a zone in the profile which occurs at a depth of 10.5-22 metres, and the bulk of the nickel in this zone (42-80%) is associated with the

Jan 1, 1974

An experienced drill operator is able to make a log of a drill hole defining physical properties of the earth such as hardness or structure as they vary with depth. This log is based on intuition or how the drill æfeelsÆ. Rock characterisation using measure while drilling (MWD) parameters aims at refining this intuition into a package that accurately defines the properties of the subsurface as the drill bit propagates. Subsurface investigation using MWD parameters aims to combine physical drill parameters: Pull down force, rotary speed, penetration rate, torque and vibration in such a way to yield real time rock properties. MWD is investigation in its most primitive form, put simply MWD is merely a physical probe æfeelingÆ what the rock mass is at depth.

Jan 1, 2001

By M J. Davies, R S. Davies

Despite increased expenditure, the global discovery rate of world-class ore deposits has been in decline for over a decade (Schodde, 2017). Mineral exploration has traditionally followed an empirical approach, searching for evidence of mineralisation upon the surface of the planet, then drilling to define the extent of an ore body beneath the surface. As outcropping deposits in well-defined areas are depleted, there is a need for exploration to extend to less well-explored search spaces. One popular new frontier is exploration at greater depths beneath the Earth's surface. However, exploring for deep deposits with limited surficial evidence requires the implementation of predictive targeting methodologies (Hronsky, 2011; McCuaig & Hronsky, 2014). The Mineral Systems Concept (Hronsky & Groves, 2008; McCuaig et al., 2010) provides a framework for predictive exploration targeting. Ore deposit formation is recognised to be a focused mineralising event. These events represent self-organising critical systems and are underpinned by the interaction of complex, non-linear processes. Through the collection and analysis of datasets that map mineralising processes, it may be possible to predict the size and location of resultant ore bodies. CITATION: Davies, M J and Davies, R S, 2018. Beyond below-ground geological complexity: Developing adaptive expertise in exploration decision-making, in Proceedings Complex Orebodies Conference 2018, pp 95–98 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By Toivanen R-M, Leinonen O, Pekkarinen H

This paper presents developments in designing an integrated mine control system at Kemi mine. The aim of this paper is to present the general structure of the system and to outline some features of the process control strategies. The results o

Jan 1, 1998

For the past 40 years, underground trucking using diesel powered or electric wheel driven vehicles, either conversions of surface trucks, or purpose built, has been the preferred means of ore and waste transport in underground mining. The relatively low capital cost, flexibility and requirement for minimal infrastructure means that trucking systems are selected in the early stages of a mining operation. An increase in the carrying capacity of trucking systems with dimensions to operate within existing development excavations is the solution to long term ore and waste underground haulage systems using trucks. The next generation of underground trucks will be low profile articulated trucks with carrying capacities up to 60 t.

Jan 1, 1998

By J-P Franzidis

The Floatability Characterisation Test Rig (FCTR) is a self-contained, highly instrumented, mobile pilot plant. It was developed as part of the AMIRA P9 project, primarily to determine ore floatability characteristics and to develop and validate flotation plant modelling, scale-up and simulation methodologies. This paper describes the use of the FCTR in validating the AMIRA P9 flotation model and modelling methodology. In 2001 the FCTR was installed and operated in parallel with WMCÆs (now BHP BillitonÆs) Kambalda Nickel Operation. The FCTR was operated using four different circuit configurations of increasing complexity. Metallurgical surveys, cell characterisation measurements and batch flotation tests were performed around each circuit. This allowed the calibration of a number of flotation models using a combination of data from one, two, three or four circuit configurations. The calibrated flotation models were then validated using predictive validation. To do this, data around a further five FCTR circuit configurations were collected (three of which are presented in this paper). The performance of each of the five circuit configurations was predicted using JKSimFloat V6.1 and the parameters from the various calibrated flotation models. The predicted performance was compared to the experimentally determined performance of each circuit. The validation of the AMIRA P9 model was shown to be largely successful except in the case where the reagent addition (depressant) to the validation circuit was different to that in the calibration circuits. The results also provided information regarding the required complexity of the calibration circuit and how many calibration circuits are required to obtain an accurate prediction of circuit performance. These results have increased the confidence in the AMIRA P9 flotation modelling methodology and have provided important information on what data must be collected to allow the accurate prediction of plant performance using the floatability component modelling approach.

Jan 1, 2007

By J Harris, J Turner, P Kirsch

Coal mining is recognised globally as a hazardous activity, and as a result operates under high levels of regulatory and public scrutiny while managing a workforce operating in a high-risk environment. Mining companies have developed sophisticated risk assessment procedures, management systems and personnel competency requirements that facilitate the safety and health of employees, and Australia is a world leader in coal mining safety and health.RISKGATE is an Australian Coal Association Research Program funded online platform that delivers broad cross-industry knowledge about current practice in the identification, assessment and management of coal mining risk. Centennial Coal has engaged with the RISKGATE program, managed by the University of Queensland’s Minerals Industry Safety and Health Centre, since its inception in 2010, and contributed topic experts to many modules, including underground topics within the geological and geotechnical domain (strata underground, outburst, coal bumps and bursts, and inrush).In 2013, Centennial Coal experienced significant unexpected strata failure at the Mandalong mine without any personal injury or fatality. This paper presents a case study in the application of RISKGATE to management of this unwanted event, the steps that were implemented, the information that was sourced and the contribution that RISKGATE made to the final outcomes. The Australian coal industry is encouraged to embrace our knowledge platform, and to also openly share processes and practical outcomes that result from integration of RISKGATE in mining operations.CITATION:Harris, J, Turner, J and Kirsch, P, 2014. Case study – application of RISKGATE to managing strata failure in an Australian coalmine, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 55–60 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By J E. Everett

Ore selection is generally a highly subjective task, with emphasis on producing product with a consistent target grade matching a perceived market requirement. A composite selection criterion ‘Comp’ (a linear function of the grade vector) can be used to maximise ore tonnage at a specified target grade (in Fe and contaminants) extractable from a block model. The blocks correspond to the selective mining units, with grades interpolated from diamond drill hole data. An iterative procedure has been developed to identify the coefficients and cut-off value for the composite function ‘Comp’, maximising potential ore tonnage at target grade.Commonly, target grade is predetermined by marketing; however, there is no guarantee that maximising ore tonnage at a specified target grade maximises the potential value of the mine. If the value of ore could be expressed as a linear function of the grade components, then these coefficients would be appropriate for the selection criterion ‘Comp’. The cut-off value for ‘Comp’ would correspond to the marginal cost of production; all blocks with a ‘Comp’ score above the cut-off would be classified as ore; and the cumulative grade of these ore blocks would be the average product grade over the life of the mine.Unfortunately, no such value function for iron ore is generally available. Methods for estimating the value function are discussed, using the spot price and sensitivities based either upon operational tolerances for Fe and the contaminants or upon published price differentials. This approach has been applied to an anonymous Pilbara deposit with about one million blocks averaging 1.1 kt. It is shown how the optimal target grade, cut-off grade and maximum tonnage can all be explored as a function of marginal cost and iron ore price. Alternatively, given marginal cost and an iron ore price, the effects of changing the tolerances (and therefore the relative costs of the contaminants) can also be explored.It is suggested this procedure can enable informed decision-making for an iron ore mine. Rather than setting final policy for the entire life-of-mine, the method enables target grades and tonnage estimates to be revised by re-computation as the mine life proceeds to recognise changes in market conditions and knowledge about the resource.It should be emphasised that this paper is concerned with ore selection rather than ore sequencing. Appropriate ore selection is a necessary but not sufficient condition for maximising value. Having identified the set of blocks that potentially maximise value, the sequence in which they are mined will present a trade-off between producing at constant grade and extracting high value ore early. The sequencing issue is not considered here. It is shown that optimum ore selection for an open pit mine is independent of any consideration of discount rates, although ore sequencing will depend upon the time value of money if the product grade is to vary across time.CITATION:Everett, J E, 2015. Ore selection to maximise value, in Proceedings Iron Ore 2015, pp 443–448 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By S Juras

To our geologists at Eldorado Gold Corporation, the release of the gold assays on a new ore zone causes a flurry of excitement. But to our metallurgists, that news is often greeted with the question ‘What’s the sulfur grade’? In our company, we operate and manage projects whose end-product will either be auriferous sulfide flotation concentrate or gold doré. Almost all of the steps in the ore processing are related to sulfur (in this paper specifically sulfide sulfur). So why do we geologists wait until late in a project or into production before collecting sulfur data for mine planning and ore control purposes?Gold deposits associated with sulfides commonly use a metallurgical process that begins with a flotation step to recover gold into a smaller mass known as flotation concentrate. Often, this step solely targets the sulfide minerals with gold only coming along for the ‘ride’. As a result, the gold grade in the concentrate is primarily influenced by the ratio of gold to sulfur in the feed. Should this concentrate require a refractory process downstream (eg pressure oxidation), knowing sulfur grade is critical as sulfur controls heat balance in the process. Regardless, we need sulfur models to be as robust as gold models, and created much earlier in the project evaluation process.Sulfur models require quality data collected at the same density as gold samples. Analytical methods must match expected grade ranges and quality assurance quality control (QA/QC) protocols and must be of the same integrity as in use for gold. Sulfur models will then be created by their own data analyses, interpolation protocols and validation. Furthermore, ore control systems should be designed for regular sulfur monitoring to ensure and enhance downstream value. Given time it should become habitual for geologists to likewise ask, ‘And what’s the sulfur grade’, or more specifically, ‘What’s the gold to sulfur ratio’?CITATION:Juras, S, 2017. Sulfur – the new geometallurgical grade in gold-sulfide deposits, in Proceedings Tenth International Mining Geology Conference 2017, pp 199–202 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By G J. Zhang

The shape and particle size distribution of caved ore mass in sublevel caving were investigated in this study. The paper first reviews the main factors affecting the shape and characteristic of caved ore mass in sublevel caving and then through the experimental blast testing with cement-sand concrete models, the shape and particle size distribution of caved ore mass were found out. The experimental results indicated that the shape and particle size distribution of caved ore mass was similar to that of the drawn loose body. This finding presented a new perspective for the future study on the ore drawing theory and on the optimisation of structural parameters of sublevel caving. The structural parameters must meet the principle that the shape of the drawn body is in consistency to the shape of caved ore mass.

Jul 11, 2011

Mine reconciliation is the practice of comparing the tonnage and grade of material processed by the mill with the tonnage and grade of ore in the reserve model of a deposit, and with the tonnage and grade in the grade control models used to de

Jan 1, 1998

By J Tickner, Y Van Haarlem, G Roach, D Abernethy, M Smith, J OÆDwyer

The development of novel technologies capable of real-time, high-accuracy, automated analysis of gold, other precious metals and mineralogy, both in ore samples and directly on process streams is reported.X-ray fluorescence (XRF) analysis is widely used for process stream monitoring of base metals. However, detection limits are generally a few parts-per-million (ppm) or larger, precluding the use of this method for monitoring precious metals. Complex interferences with other elements also limit accuracy. An XRF slurry analyser that uses advanced data-analysis techniques to resolve overlapping fluorescence lines, achieving detection limits in the parts-per-billion (ppb) range has been developed. This allows feed, concentrate and tailings streams in precious metal applications to be monitored in real-time. An extended trial of our technology in a platinum group element concentrator and laboratory tests on gold process slurries in the 0.1 - 2.0 ppm concentration range is discussed.Analysis of process stream mineralogy can provide useful information to supplement conventional elemental data. An on-stream X-ray diffraction analysis technique that provide real-time mineral and elemental measurement of process slurry streams has been developed. Both X-ray techniques can be combined into a single on-stream analyser to provide simultaneous elemental and mineralogical information. The successful trial of a combined XRDF (X-ray diffraction and fluorescence) slurry analyser is also reported.It is widely recognised that rapid, accurate analysis of grade is an essential prerequisite for optimising the efficiency of exploration, mining and processing of metals ores. The low grades of precious metals ores, such as gold and the platinum group elements, have led to fire assay becoming the predominant analysis technique. Significant drawbacks of fire assay include long turn-around times, limited absolute accuracy, high costs and requirement for skilled operating staff. For rapid measurement of gold samples, a technique that allows the gold content of large samples to be determined absolutely with high accuracy in less than two minutes using activation with high-energy X-rays has been developed. The method is non-destructive, has detection limits in the low ppb range, is capable of measuring slurries, ground or crushed solids with minimal preparation and can be made fully automatic. Initial results from laboratory trials are presented.CITATION:Roach, G, Abernethy, D, OÆDwyer, J, Smith, M, Tickner, J and Van Haarlem, Y, 2013. Advanced instrumentation for analysis of exploration, mining and process materials, in Proceedings World Gold 2013 , pp 277-282 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By S Hayton

While coal seam gas is considered to be an unconventional gas, the proliferation of areas under exploration and development mean that it is rapidly becoming main stream. The potential of New Zealand's coals to produce coal seam gas has been recognised for some time. However, key market drivers have not been suitable for the progression of this potential into reality. Kenham Holdings Ltd and CRL Energy Ltd, recognising the potential for the gas in New Zealand have initiated what is the largest ever assessment of New Zealand's coal seam gas potential. The premature demise of the giant Maui field has raised the focus of new gas developments and has increased interest in what we are doing. Over the past couple of years Kenham Holdings Ltd and CRL Energy Ltd have approached the assessment of the coal seam gas potential in a staged programme. Preliminary assessment of the data on the permit areas indicates that the potential resource may be up to 500 PJ. To date, preliminary appraisals have been completed or are underway on a significant number of fields. Exploratory drilling has been completed or initiated on several of those fields, with results from this work being fed into the preliminary modelling as it has become available. Given that in many of these areas there is no pre-existing information concerning their gas potential and world wide experience with lignite is practically nonexistent, it has been a steep learning curve with many surprises. However, initial gas content results and preliminary gas flow models have been on the whole, rather pleasing, with the commerciality of some developments already apparent.

Jan 1, 2003

By Gray E, Banks J

In mine site revegetation, exotic grasses are more commonly used than native grasses. This is due to unavailability of native grass seed on a commerical scale and lack of information on agronomical aspects of native grasses. This paper lists a number of native grass species that have the potential to grow well on mine sites, and provides some information on their seed collection, processing and germination. Further, it demonstrates via results of a field trial conducted at Ranger Mine spoil the relative performance of ten native grasses and Rhodes grass. It is concluded that (i) some native grasses have similar ability to grow on mine spoils compared to Rhodes grass and (ii) the use of native grasses have added advantages in ecosystem restoration.

Jan 1, 1994

By Hare S. M, Lumsdaine I, O&apos

Converter slag assaying 3.7 per cent Cu is produced by Mount Isa copper smelter at a rate of up to 180 000 tonnes per annum.Priority is given to the processing of ore, however concentrator capacity periodically exceeds that of the mine and the opportunity is taken to treat converter slag. It is processed in batch campaigns, typically through the Copper Concentrator, but the Hilton Concentrator has also been used. Slag and ore are kept as separate as possible, since each has an adverse effect on the flotation performance of the other.

Jan 1, 1993

On the 18th November, 19'58, the first coal was delivered to the Morwell Power Station from the adjacent Open Cut using conveyors for the transport of the coal from the working face to the boiler bunkers. As the cut develops the coal seam will be worked for its full depth of about 360 feet from four benches, each feeding a conveyor line along th.e face and up out of the cut to the power station and briquette factory. By 1970 the estimated maximum daily demand reaches 60,000 tons and the total annual output 18 million tons. The complete conveyor installation will then total some 9 miles with a capital cost of over £3~ million.The choice of conveyors in place of the more usual rail system was made possible by the development of movable belt conveyors which use mechanical conveyor shifting, high belt speeds and flexible high strength belts and the paper deals with these and some other aspects of the scheme.INTRODUCTIONThe development of brown coal deposits is usually based on open cut workings equipped with a few large dredgers giving an almost continuous output of coal or overburden which has to be hauled a comparatively short distance. These are ideal conditions for conveyor operation, and it is surprising that, until recently, rail transport has been used almost exclusively in brown coal open cuts. In some cases inclined conveyors have been introduced to take the coal from the coal levels up out of the cut to bunkers at groundlevel, but trains have been left to operate between the ditch bunker feeding the conveyor system and the dredger.

Jan 1, 1960

The history of the down draught Dwight- Lloyd system of iron ore sintering in Australia is developed. Characterisation of the broad process is given for one plant, and regional divergences from the reference practice are noted and briefly analysed. The subject of the development of high basicity sinters is introduced, and regional differences in approach and results are Examined.

Jan 1, 1972

By D Xu

BHP Billiton Iron Ore is one of the world’s premier suppliers of iron ore. It currently has operations in Western Australia and Brazil and also has some iron ore interests in West Africa.BHP Billiton’s Optimisation R&D team has developed a proprietary mine planning optimisation tool that uses a mixed integer linear programming (MILP). This tool is called Blasor and it is used to rapidly evaluate the resource development potential (RDP) scenarios for the company’s business development strategy. In addition it generates life of asset (LOA) mine plans for the company’s operations and growth projects. The Blasor optimiser maximises the discounted operating cash fl ow (DCF) as the objective function, subject to mining, processing and transportation capacity constraints and blended product quality constraints. The paper will outline how Blasor has been applied to the resource development potential (RDP) strategy scenario studies, growth project evaluations and LOA mine planning within BHP Billiton Iron Ore.The practical application of Blasor to resource planning optimisation within BHP Billiton Iron Ore has demonstrated the value of such a tool for optimising strategic directions through the evaluation of a number of carefully proposed scenarios and maximisation of operational decisions, such as cut-off grade, open pit development sequence, etc. Particularly for the company’s business development direction studies, Blasor plays the role of a fair valuation tool in that it discovers the most valuable resource development scenario, thus establishing a sound basis for comparing the economic merits of each scenario.

Jul 11, 2011

By Zhou Y, Karmis M, Haycocks C

Hazard analysis utilizes interaction mecha- nisms in combination with geologic, structural and mining conditions to delineate areas of potential damage in seams subject to interaction. Using characterizations of conditions peculiar to multi- seam mining, such as innerburden thickness, geol- ogy and structures, initial interaction contour maps can be constructed. Geologic hazard analysis is then carried out on roof, pillar and floor condi- tions in the affected seam using lower seam rock properties and layout geometries in the overlying seam. Either safety factors or damage ratings can then be developed representing degree of hazard in the lower seam. The final hazard map shows both the aerial extent and magnitude of potential dam- age from interaction.

Jan 1, 1992