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Visual computing opens the design process to a wider audience and allows rapid communication of mine plans to all stakeholders. The integration of software and hardware technologies that take advantage of a graphical environment will continue to improve both long-term and short-term mine design (Figure 1). A good design must be adaptive to respond to decision changes as the mine develops and more information becomes available. The constraints on mine design predicate careful analysis in order to operate the mine as efficiently and safely as possible.Continuous improvement in mining is assured by developing innovative technologies that target mine survey, drill and blast, modelling, short-term design and pit and stope optimisers. The design life of a mine has to be sufficiently long to ensure the mine is commercially successful, justifying the high start-up capital costs. Being able to execute a plan so that it honours the design realises the rewards of computerised mine planning and the long-term investment in data acquisition.

Sep 26, 2011

Pyrrhotite is pyrophoric when in a finely divided form. The problems of disposing of large quantities of finely divided pyrrhotite separated out by metallurgical processing from ore are formidable. In the case of an underground mine, a solution to the problem of disposal is to place the pyrrhotite in the stoped out areas and seal from any air supply. Further, the pyrrhotite could be diluted with tailings which would reduce the possibility of combust- ion. Several enquiries to various centres and authorities have shown that the products of the slow oxidation of pyrrhotite with moisture present can cement an inert matrix into a stable fill similar in physical prop- erties to fill stabilised with Portland cement. Stabilised fill can be used to advan tage with a suitable mining method to provide high recovery. The investigation demonstrated that air and 15% w/w water must be present for the fill to harden and that the sizing of the particles is a critical factor in drainage of a hydraul- ically placed fill and subsequent even harden- ing of the fill in a stope. With the materials used in the experiments in which the - 51 micron component of the tailings had been dis- carded, an optimum mix was found to contain 4:1 tailings/slag ratio and an overall pyrr hotite concentration of 8% (all proportion by weight). Approximately 34 days after drain- age to 15% moisture in natural air flow condit- ions, an unconfined compressive strength of 1.862 MPa was attained. A subsequent experi- ment was conducted with a sample of optimum mix in a pipe one metre long in forced air flow conditions. At a superficial velocity of 3.Om per hour the mix required 155 hours to harden to 1.862 MPa after drainage to 15% w/w moisture content. The pressure drop bet- ween the top and bottom of the mix in the pipe remained constant at 9 KPa/metre length. This result suggests that forced air flow conditions will increase the rate of hardening. No dangerous effluents were detected in the course of the experiments which could affect mine equipment or personnel.

Jan 1, 1973

A pilot plant has been constructed for the low temperature carboni-zation of Wallarah (N,S,W6) coal at the rate of 300 pounds per hour. The plant was built and tested at Australian Mineral Development Laboratories for Broken Hill Pty, Ltd. Char product was required within the specifi-cation 15.5 `S' 1 per cent volatile matter. The design was based c atz an entrained state carbonizer developed by Parry and U.S. Bureau of Mines co-workers at Denver, U.S.A. The method involved the carbonizatioan of fine coal by entrainment with air in an externally heated reactor.. The heat required for carbonization of tits coal was supplied to the be, both through the reactor walls and also by internal cambustion of products .

Jan 1, 1963

By P York

The study commenced in October 2012, to understand the basic ecology of the spotted-tailed quoll (Dasyurus maculatus) and to confirm whether the species utilise previously mined land on the Mt Owen mine site that was rehabilitated in 1996 to 2011, as part of their home range. The spotted-tailed quoll is a widely distributed marsupial carnivore that is listed as rare or threatened in every state in which it occurs. The species is a forest-dependent marsupial carnivore that occupies a wide range of habitat types (Long and Nelson, 2004).The first part of the study involved trapping a spotted-tailed quoll and fitting the individual with a combined global positioning system / ultra high frequency (GPS/UHF) radio-transmitter collar (Telemetry Solution – Quantum 4000E). The benefit of the GPS/UHF collar is that it records locations (or fixes) at intervals programmed by the user. The UHF component allows the researcher to locate the individual at a frequent interval, and the Quantum 4000E also has a remote download function, enabling the GPS data stored in the collar to be wirelessly transmitted between the collar and researcher. The benefit of this new technology is that the animal does not need to be repeatedly captured to retrieve the GPS data.Daytime searches are also undertaken using the UHF receiver to locate the individual and locations of daytime denning and latrine sites. The location of each den site is recorded using a hand-held GPS. Data downloaded from the GPS collar is then imported and mapped using computer software program ARCGIS (geographic information system), to overlay the data points onto aerial photography.Results demonstrate that threatened species will utilise rehabilitation areas post mining. The data presented will be used to develop a greater understanding of threatened species ecology in and around rehabilitated areas, which will assist in the planning and design of native forest rehabilitation areas.CITATION:York, P, 2014. Mt Owen Mine spotted-tailed quoll study, in Proceedings Life-of-Mine 2014 , pp 591–596 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By C Itotoh, K O’Halloran, L Karlson

Global methods used to explore for minerals have progressed relatively slowly since the development of the first diamond core drill in 1863. Since then, key developments such as wireline geophysics (1920s), the tricone drill bit (1930s) and aeromagnetic surveys (1940s) all occurred in response to global events. In this project, BHP’s WAIO Geoscience operations team hypothesise that a global movement towards a greener future as well as an increasing intolerance for safety events will drive another step change in exploration methods. We have leveraged our relationships with exploration contractor partners and industry leaders to develop a realistic vision for 2033 and beyond, where drill rigs, earthworks and geophysical units are operated and maintained remotely; emissions of dust and waste are eliminated; hazardous energy sources are controlled; procurement is based on sustainability rather than cost and carbon emissions are tracked with the same rigour as production metrics. We have combined these visions into a series of graphical illustrations with the aim of inspiring ourselves, our vendors and our peers to collaborate further on producing a step change in our industry.

Sep 18, 2023

By E Donskoi

In order to develop downstream processing routines for iron ore and to understand the behaviour of the ore during such processing, extensive mineralogical characterisation is required. To determine mineral associations, mineral liberation and grain size distribution, imaging techniques have to be used. There are two main imaging techniques used for the characterisation of iron ore, ie, Optical Image Analysis (OIA) and Scanning Electron Microscopy (SEM). In this article a QEMSCANTM system is used as an example of SEM methodology and results obtained from it are compared against results obtained by the CSIRO ‘Recognition3/Mineral3’ OIA system.Both OIA and QEMSCANTM systems have advantages and drawbacks. Even though the latest QEMSCANTM systems can distinguish between major iron oxides and oxyhydroxides, it is still problematic for QEMSCANTM to distinguish between iron ore minerals very close in oxygen content, eg haematite and hydroheamatite, or between different types of vitreous goethite.QEMSCANTM also can misidentify minerals with close chemical composition, ie haematite as magnetite and vitreous goethite as haematite. In OIA, iron minerals with slight differences in their oxidation or hydration state are more easily and directly recognisable by correlation with their reflectivity. In both methods, the presence of microporosity can result in some misidentification, but in SEM methods misidentifi cations due to microporosity can be critical. Low resolution during QEMSCANTM analysis can significantly affect the textural classifi cation of particle sections.The main conclusion of this study is that, for low iron content ores or tailings, QEMSCANTM can provide much more detailed information on the gangue minerals than OIA. However, for routine characterisation of iron ores with high iron content and containing a variety of iron oxides and oxyhydroxides, OIA is a faster, more cost-effective and more reliable method of iron ore characterisation. A combined approach using both techniques will provide the most detailed understanding of iron ore samples being characterised.

Jul 11, 2011

By Waterhouse J. D, Harris B. M

This paper briefly describes the construction in 1979/80 of a 70m deep trial open pit coal mine near Bowmans S.A. and describes more fully the hydrogeological aspects of the exercise. The primary purpose of the Trial Pit was to provide a large sample (700 tonnes) of coal for combustion tests to be carried out in West Germany and the United States of America. Consideration was given to obtaining the sample of coal by drilling and by shaft sinking as alternatives to open pit methods. It was expected that economic mining of the deposit on an operational scale could only be achieved by open cut methods and it was recognised that major uncertainties existed in planning such a mine in the deep unconsolidated multi-aquifer deposit. It was therefore elected to obtain the bulk sample by constructing a trial open pit, which would be closely monitored to provide as much data as possible for future planning of a full scale mine. The dewatering of the Trial Pit was achieved using 26 deep pumping wells, assisted in the later stages by several hundred well points. This was probably the largest dewatering project currently in operation in Australia.

Jan 1, 1981

By V Lishchuk, C Lund

"Geometallurgy aims to improve resource efficiency by creating a spatial model of an orebody in order to forecast ore processing behaviour. This enables calculation of the economic value of each ore block and the use of this information for production optimisation and hence an improved economic return. Modelling uses different approaches to link geological information with mineral processing: traditional approach uses chemical elements; proxy approach – small-scale geometallurgical tests; and mineralogical approach – minerals.A geometallurgical model is obtained during execution of a geometallurgical program encompassing the entire value chain of ore processing. Available methods for establishing a geometallurgical model are in many cases limited and not yet comprehensively validated. Some of the limitations include: sampling density, assaying methods and quality, forecast accuracy block model content, geostatistical solutions for non-additive components, blending and assessment of positive impact of geometallurgy on the project. Synthetic ore models combined with process simulations and production scheduling, based on strong case studies, present a viable way to address these shortcomings. Such synthetic ore models will have realistic elemental and mineral distribution, textural attributes and 3D variability for input into the design of an appropriate geometallurgical program.A synthetic orebody was created for an apatite-bearing iron deposit. Variability in modal mineralogy was described by geostatistical parameters combined by a set of linear and trigonometric functions. The generated synthetic deposit model was used to develop a mine production plan to generate a simulated process feed. The process feed had detailed information required for beneficiation process simulation: modal mineralogy, chemical composition of minerals, grain size and specific gravity. The synthetic system was used to measure benefits that a geometallurgical program developed for real cases could provide, compared to production where only head grade is optimised. These include a reliable sampling strategy and confidence in the feed-quality forecast for economic evaluation.CITATION:Lishchuk, V, Lund, C and Lamberg, P, 2016. Development of a Synthetic Ore Deposit Model for Geometallurgy, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 275–286 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By M Yahyaei, F Reyes, R Lage, V Jokovic

Equipment wear is strongly related to the performance of grinding circuits. In particular, SAG mills are subjected to the wear of their shell liners and grates. Changes in lifter height and face angle impact mill performance, while classification at the mill discharge is also affected as grates wear out. Moreover, liner mass loss caused by wear affects how operators interpret readings of sensors such as load cells or bearings pressure. Automating and optimising grinding circuits under these constrain becomes challenging due to the nonlinear and dynamic nature of the system. The operation of SAG mill grinding circuits remains largely dependent on human intervention, which frequently results in inconsistencies in performance across shifts, reflecting the operator’s personal preferences, experience, and other human factors. The influence of human factors can be reduced by careful training of operators as well as by automation using advanced supervisory control. The latter approaches could benefit from the development of dynamic process models that consider the effects of wear on the performance of equipment over time. This paper presents detailed industrial data showing the effects of wear on SAG mill performance. Additionally, a dynamic SAG mill model that accounts for these phenomena is proposed and demonstrated in a simulated environment. This model is shown to mimic the effect of wear on the performance of industrial scale mills and the operational constraints they are subject to, thus extending traditional SAG mill models. Incorporating wear into modelling and simulation platforms can improve the understanding of the effects that wear can have on the performance of key assets in comminution circuits and may allow the development of more robust model-based advanced process control strategies.

Aug 24, 2022

By R McIlwraith, B Breul

Two case studies are presented in this paper. The first one discusses a roller compacted concrete water supply dam that was constructed in El Mauro in Chile to provide water for agriculture activities downstream of a copper mine during the dry season. The 23 m high dam used a bituminous geomembrane (BGM) as the low permeability upstream facing element on the dam to control seepage through the dam. This is the first time that a BGM has been used in this application. A deep cut-off trench was used to control seepage beneath the dam and through the abutments. This paper briefly presents the design of the dam, including selection of the concrete mix and maximum aggregate size that the use of the Coletanche BGM allowed, and provides details of the construction, quality control and assurance of the installation of the BGM. An ultrasonic apparatus was used as part of the quality control on the BGM seams.The second case study discusses a tailings dam in Cerro Lindo, Peru (near Chincha), where a watertight BGM was installed on the upstream face. Results are presented of the survey done by a consultant on the behaviour of the dam and in particular of the BGM following an earthquake of magnitude 8.1 in Chincha close to the site. These findings on-site were checked by trials in a laboratory in California. Test results are given and explained.CITATION:Breul, B and McIlwraith, R, 2015. Case histories – roller compacted concrete dam waterproofing with a bituminous geomembrane in Chile and a tailings dam in Peru subject to an earthquake of 8.1 magnitude, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 367–372 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By F C. D Michelin

Blast fumes are a significant health risk to underground workers, containing several dangerous gases such as carbon monoxide (CO), nitrogen oxides (NOx) and ammonia. To ensure safe working conditions, workers are not normally allowed to re-enter a mine until the gases are cleared. To predict if gases can be cleared efficiently, simulations can be performed to estimate the gas levels following a blast. For accurate modelling, a calibrated airflow simulation is required in addition to blast-specific parameters such as the yield rate (representing the amount of gas released per kg of explosive) and the dispersion factor (representing how quickly the gases can enter the air stream from the explosive site). Those parameters are not easily determined, as they will vary from blast to blast. Many post-blast gas recordings on mine sites were studied and the correct parameters were determined to ensure an accurate gas simulation. The variability of the results was then analysed and correlation to known parameters is suggested. Finally, recommendations on how to determine the correct parameter are presented.

Oct 12, 2022

The Mt Sinivit gold project is located approximately 50km SSW of Rabaul in the Baining Mountains of the Gazelle Peninsula, East New Britain Province. The deposits were discovered in mid- 1983 and form part of a larger 26km long zone of variably aurif- erous quartz veining. There are no surface indications or previ- ous records of any prospecting activity or production from the region. The Mt Sinivit deposits consist of a series of oxide and sulphide reserves and resources contained in the Wild Dog (South- ern, Central and Northern oxide zones; Northern sulphide zone) and Kavursuki veins. The proposed exploitation of the oxide reserves by a series of small-medium sized open pits has been fostered by the PNG Department of Mining & Petroleum (DMP) as part of a government policy to encourage the development of a small-medium sized mining industry in the country. The aim of this paper is to document the steps and procedures involved in obtaining the grant of a Mining Lease emphasising the time and the expenditures required during each step of the approvals process for the Mt Sinivit project.

Jan 1, 1997

By Jaczkowski B

The lower orebody (LOB) at Chingola Divi- sion of Nchanga Consolidated Copper Mines Limited (NCCM) accounts for approximately 30 per cent of the total copper production for the company. The uniformity of the geology of the orebody lends itself readily to a computer based ore reserve calculation and accounting system. The mining units are physically defined such that a hierarchical type of com- puter file organisation can reflect the existing physical interdependencies. In 1972, a project team consisting of one representative from each of the mine planning, operational research, and computer services departments was formed to investigate and to define the technical mining requirements of the dynamic ore reserve system (DORS). The system was finally implemented in 1975ò

Jan 1, 1977

The Australian Constitution specifies certain powers of the Commonwealth Government to be used in its capacity as the national government. Certain of these broad powers result in the Com- monwealth having a facility to play an important part in the development of the mining industry. The State Governments, however, by virtue of their wide powers to regulate matters within the boundaries of a particular State, are more directly involved in the day to day administration and standards of activities of mining operations. In this respect the Common- wealth has something of a dual role because of its "State-like" responsibilities for the mainland Terri- tories. The components of the role that the Common- wealth Government discharges in relation to the mining industry are qualified to varying extents at particular times by the political persuasion of the Government. In absolute terms the components are as follows. 1. Economic management. The Commonwealth's fiscal and monetary policies have an important effect on industry as well as on State finances. In particular, the taxation regime employed by the Commonwealth Government is of direct importance to economic decision-makers in the mining industry. 2. International matters. International trade and commodity matters are, more and more, becoming an everyday part of the conduct of a nation's foreign affairs. 3. Exports. The Commonwealth Government, via the constitutional powers over overseas trade, have exercised varying degrees of control over mineral exports to achieve particular objectives. 4. Foreign capital and investment. Australia in general, and the mining industry in particular, is and will continue to be a net importer of capital. There appears to be bipartisan political agreement in Australia that foreign investment policy must be enunciated to ensure that investors. are in no doubt that Australia welcomes beneficial investment and technology from overseas. 5. Environment and Aborigines. Governments, both Commonwealth and State, have in recent years become more involved in these areas in response to their interpretations of community aspirations. 6. Energy. Access to assured supplies of energy is now viewed, by Governments worldwide, as a desirable asset to ensure the well-being of a nation's people and industries.

Jan 1, 1978

By Russell J

A sustained drop in the grade of Mount Isa lead-zinc-silver ore occurred in mid 1980. It was decided to increase concentrator throughput from 200 000 to 240 000 tonnes/four week period to maintain budget metal production. To achieve this increase whilst maintaining acceptable grinding and flotation performance, crushing plant final product size had to be reduced from 100%-13mm to 1000-11.2mm. The goal in the crushing plant was to achieve a 20% increase in throughput with a 20% decrease in the top size of the product. This was achieved by operational changes to improve plant availability and optimisation of the existing crushing and screening equipment Performance.

Jan 1, 1978

By O Arafat, R E. McIvor, K M. Bartholomew

It is well known in the industry that good classification system performance is vital to efficient ball mill circuit performance. But what is meant by good classification system performance, and how is it achieved? Unfortunately, the perceived complexity of classification systems, and the day-to-day time demands placed on the practicing metallurgist, all too often put the low-hanging fruit of classification system optimisation in the ‘I’ll do it later’ basket. Additionally, lingering confusion about basics such as the relationship between circulating load ratio and ball mill circuit performance makes the optimisation objective seem nebulous to both plant metallurgist and designer.Some of this confusion can be eliminated by taking a step back from the overwhelming detail of sharpness of separation curves, circulating load ratios, cyclone feed pressures, vortex and apex sizes etc, and focusing on the purpose or function of the classification system – to apply mill power to particles that need further size reduction! The classification system efficiency (CSE) metric captures how well the classification system is performing its function with two quick and easy size distribution analyses.Once CSE is understood and implemented as the optimisation criteria, well-tested methods for improving CSE can be implemented and quickly measured at plant scale to give confidence that the right change was made.This paper will describe CSE and how it is measured in practice. Next, a guide for improving CSE through manipulation of design and operating variables in the classification system will be provided. Examples and case studies will illustrate the gains in ball mill circuit efficiency that can be achieved by maximising CSE.CITATION:Bartholomew, K M, McIvor, R E and Arafat, O, 2018. A guide to maximising ball mill circuit classification system efficiency (CSE), for operators and equipment designers, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 553–558 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By D A. Sims

This paper outlines the contributing factors to a series of erroneous Mineral Resource estimates which led to considerable loss, including significant reduction of mine life and consequently a large write-down of asset value. The error prompted divestment of the mineral asset in the short-term by the owners, a major mining company. There were multiple and complex contributions to the result: • The mine was undergoing a transition in the deposit geology with increasing depth that was not accommodated in the models. Early indications of the geological transition in initial drilling were generally unrecognised in resource modelling. The shortcomings of the models became apparent with increasing infill drilling and subsequent production reconciliation. • There was a lack of recognition of, and confidence in, site-based input and skills by corporate technical management. The site had a reputation internally for over-delivery to plan early in its life and that supported the anticipation of ongoing metal delivery into the mine plan by management. • A corporate lack of confidence in site being able to adequately domain the mineralisation led to the use of a CIK domaining process, rather than one which was geologically based. This domaining process led to gross over-statement of mineralisation trends reflected in the subsequent OK estimate. • Timelines on the outsourced estimation process were so short that validation was not possible. Obvious errors in the estimate versus data were not able to be used to correct the issues and the site’s Competent Person sign-off occurred without adequate checks. This case study is presented to reinforce the concept that Mineral Resource estimates are not solely based on the ability of the Competent Person to satisfactorily guide the process. There are usually multiple complex issues in the estimation process which need to be recognised and considered in judging reconciliations of model to actual.

May 24, 2023

By L Nicholls, A Parbhakar-Fox

Reprocessing Queensland’s historical copper tailings for critical minerals is an opportunity to circularise the state’s mining industry by converting waste liabilities into assets. Mine waste valorisation enables economic rehabilitation of legacy mining sites, improves environmental outcomes, and can establish a secondary resources sector that produces a sustainable supply of critical minerals to supplement growing global demands (Australian Government, 2023). The North-West Queensland Minerals Province (NWQMP) hosts numerous copper mines with known cobalt mineralisation (Degeling, 2020). Cobalt is a critical metal essential for green energy and battery technologies, however its global supply is at risk due to geopolitical and ethical concerns (Rachidi et al, 2021). Historically mining in the NWQMP has focused on copper, leaving cobalt to theoretically accumulate in the mine waste. First-pass geometallurgical characterisation of waste repositories by the Sustainable Minerals Institute identified Capricorn Copper as a key site for further investigation into cobalt deportment and recovery potential.

Aug 2, 2023

THIS paper deals with the handling of the various materials used in the 100-ton zinc plant at Risdon, and, in view of the magnitude of the works, the configuration of the ground covered by these works, the variety of the rnaterials used, and the large quantities, a very attractive and interesting subject is opened.The works are situated on the right bank of the River Derwent, about four miles above Hobart, the capital city of Tasmania. The Risdon works cover a space of 149 acres, the area being :3800 yards long by 2800 yards wide, and the elevations vary from 6 ft. above high-water mark at the wharf and foreshore to 163 ft. above high-water mark at the power station, these being the limiting points as regards elevation which are considered in this paper. Throughout the paper elevations are given in feet above high-water mark. Fig. 1 shows a general view of the works taken from the opposite bank of the River Derwent. The wharf is clearly shown, with SS Kekerangu loading residue; behind the wharf is seen the inclined conveyor leading to the cakine bin; further up the hill is the leaching division. No. 1 haulage runs to the left of this up to a point on the left of the power station, the large reinforced concrete building at the top of the hill. Below this is the cell room, the largest building on the plant. The roasting division, not very clearly seen, lies at the foot of the main stack, and the casting division lies to the left of this, between the leaching division and the cell room. A large wharf has been construl'ted alongside the works. This wharf is 880 ft. long and 60 ft. wide. It is capable of berthing large overseas steamers, as at low tide there is a depth of :30 ft. of water. The rise and fall of the tide at the wharf is 4 ft. 6in., and the river is navigable at all states of the tide. Just above the company's wharf...

Jan 1, 1923

This paper outlines mining practice in the South Alligator valley between 1954 and 1964. The valley is situated in the Northern Territory 130 miles south east of Darwin and trends north west. The centrally located El Sherana camp is 219 miles by road from Darwin via Pine Creek on the Stuart Highway. 64 miles of gravelled road with low level bridges and culverts which were completed in 1959, connect Pine Creek with El Sherana. This road is often impassable during severe wet season conditions. Earliest recorded production was during the years 1956-57 from the El Sherana and Palette miles, by shallow open cut and cut and fill stoping from small shafts. 4600 tons of high grade ore was processed by hand sorting of massive pitchblende followed by gravity concentra- tion. At the same time 627 tons of ore was won from a small open cut at Sliesbeck 35 miles SE of El Sherana. The second and most important phase of production was to fill two small contracts with the United Kingdom Atomic Energy Authority (U.K.A.E.A.) totalling 700 tons of U 08. About 144,000 tons of ore was mined from widely separated smal' orebodies and mining practice varied from small open cuts to gloryholes, open stoping and cut and fill stoping. In some orebodies a combination of several methods was employed to complete production. Final deliveries were made to the U.K.A.E.A. In 1964.

Jan 1, 1968