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By C McGuire

As mobile equipment electrification in underground mining continues to gain popularity, control ofheat and humidity in the workplace is becoming a key driver in sizing of ventilation and mine aircooling systems. For design and sizing of ventilation and cooling systems to be accurate, and for themine mobile equipment fleet to be sized appropriately to meet production goals, vehicle productivitymetrics, heat modelling, and energy balances for electrified fleets need to consider operation througha realistic duty cycle that is reflective of various tasks performed during a shift.The authors conducted a real-world comparison of two 8 cubic yard (14 metric tonne) class Load-Haul-Dump (LHD) machines – one diesel and one battery-electric vehicle (BEV) – performingidentical muck-haul-dump operations on consecutive days at an underground nickel/copper hardrock mine in Ontario, Canada.The battery-electric LHD averaged 8.9 per cent faster cycle time than the diesel vehicle (gross,without accounting for charging time), and was able to transport 25 per cent more material per cycledue to a larger bucket capacity. When including the charging time, average net cycle times wereequivalent for the two vehicles over the 200 cycles. The BEV carried more payload over the eighthour period due to the increased capacity per cycle.The testing identified an approximately five-fold reduction in heat output from the BEV in comparisonto the diesel LHD on a basis of heat output per tonne of rated bucket capacity. Heat output from thefast charger was found to be approximately 4 per cent of the charging rate, with negligibletemperature change observed in the main drift. External noise levels in the mine were found to be14 dB lower for the BEV during transit and 11 dB lower during bucket loading. Fuel/energy costs forBEV electricity input were approximately four times lower per operating hour than diesel fuel costbased on typical 2021 electrical and diesel unit rates for a grid-connected mine in Ontario, Canada.

Oct 12, 2022

Prior to the merger of BHP and Billiton, both companies had a keenfocus on improving their performance in health, safety, environment and community (HSEC) matters. This shared intent, albeit executed insomewhat different ways, provided an excellent foundation for the newCompany. During the integration planning phase, a team was formed toconsider the organisational design for consistently achieving world class HSEC performance. The design included the policy platform, resources, structures, standards and procedures to be implemented in the merged entity. A key aspect of the design was the fully integrated HSECManagement Standards. These Standards create the framework for theconsistent application of BHP BillitonÆs HSEC Policy at all of ourmanaged operations across the world. The Standards have their origin in similar frameworks adopted by BHP during the 1990s, as well as thewell-known quality related standards (eg ISO 14001). However, they areunique in that they combine all aspects of HSEC management into asingle integrated set of auditable standards. By combining these areas and integrating our HSEC Management Standards with other aspects of the æBHP Billiton WayÆ, we are establishing a holistic, line management driven improvement approach. Over time, the BHP Billiton Way will embed a systematic improvement philosophy that we expect will become a key source of competitive advantage. The HSEC Management Standards are consistent with ISO 14001,OHSAS 18001, the Australian Minerals Industry Code for EnvironmentalManagement and generally aligned with SA8000. While compliance withthese external standards ensures that a systematic approach andimprovement plans are in place, BHP BillitonÆs HSEC Standards gofurther to include minimum performance requirements that reflect theintent of our HSEC Policy. Therefore, implementation at site levelensures that robust systems are in place to implement our Policy and that accreditation can be achieved to external standards if required.To assess implementation of the HSEC Management Standards anaudit system has been designed which incorporates both self-assessmentand peer review. Each site is required to undertake an annualself-assessment of compliance with the Standards using a commonassessment protocol. Every three years a peer review is conducted at each site to confirm the results of self-assessment and to provide a means of sharing knowledge throughout the Company. The review teams are composed of line managers and HSEC professionals from around theCompany, representatives of our joint venture partners and independentspecialists as required. The Company has committed to public reportingof the audit results through our annual HSEC report and this is reflected in our published targets. From a wider perspective, as we in the resources industry strive tocollectively raise our HSEC performance and reputation, there may be arole for industry based HSEC Management Standards complemented bya level of independent review.

Jan 1, 2002

Greater use should be made of lineations in investigations of the engineering properties of rock masses and in structural studies guiding prospecting programmes.A prominent alignment of elongate mineral grains and stretched pebbles usually marks the primary direction in which metamorphic rocks have been extended by flow. In local adjustment zones separating masses that have extended different amounts, this lineation has been a direction of slip. Kinks and crumples resulting from this slip lie in secondary lineation directions transverse to the primary mineral lineation.During deformation relatively mobile materials move into dilatant zones caused by irregularities in primary flow directions. This secondary movement transverse to lineated, primary-flow directions is the cause of crenulations and folds with axes parallel to flow lineations.INTRODUCTIONThe arrangement of inequidimensional particles in rocks is rarely statistically random. Platy minerals tend to be parallel to bedding and foliation planes. Elongate particles and linear structures lie most frequently in certain lineation directions. The types of elongate particles in lineated rocks include needle and blade shaped mineral grains, sheared out segregations, and stretched pebbles, amygdules, and aolites.Crenulations and kinks are the most common of the linear structures involved.Faint lineations are readily overlooked. Even strong lineations have been ignored. This is unfortunate as even weak lineations may be important.Use of lineation information Well-developed lineations influence the mechanical properties of rocks. Quarry workers have long known that the mechanical properties of rock masses vary directionally...

Jan 1, 1965

By B Zhou

Geophysical borehole logging, which measures various in situ petrophysical parameters, can be used not only for qualitative interpretation such as strata correlation, but also for geotechnical assessment through quantitative data analysis. It can play an important role for safe and productive mining operations. Here we provide various applications of geophysical logs such as the estimation of the strength of intact rock or unconfined (or uniaxial) compressive strength (UCS), automated lithological/geotechnical interpretation, geophysical strata rating and orebody delineation and grade estimation. These derived parameters could provide input to control of geological and geotechnical models. This could assist site geologists and planning and production geotechnical engineers to predict and manage mining conditions on an ongoing basis. Both conventional logs such as density, natural gamma and sonic, and less common logging data such as full waveform sonic and televiewer data are examined for different applications. Although the examples used here are mainly for coal mining applications, but they can be equally applied to hard rock metalliferous mining such as iron ore mining.

Nov 8, 2021

Welcome to this 13th Congress of The Council of Mining and Metallurgical Institutions. It is twenty one years since The Australasian Institute of Mining and Metallurgy last hosted this congress and it is a privilege and a pleasure for The AusIMM to have that responsibility once more. The theme of this congress "The Twenty-First Century - Mining for Mankind" stimulates many thoughts. The first thought that it generates in me relates to the reference to the 21st Century. We are still 14 years away from it and already consideration of the beginning of the next millenium is becoming something of a cliche. If we feel like that about it now, how will we feel at the 14th Congress of the CMMI in 1990, or the 15th in 1994 or the 16th in 1998? If we do all the crystal ball gazing about the 21st Century this week, those poor devils in the 1990s will in fact have nothing to talk about. Of course that is not the case. This is a very appropriate time for those of us concerned with mining and metallurgy to contemplate the next century. Fourteen years is about the extent of forward planning necessary in the mining business. I sometimes feel that most people do not take seriously the need for long range planning in our industry. Politicians, investment fund managers, and others under severe short-term pressure to perform in our hyperactive world may nod in apparent appreciation of our long term plans but their actions in the interests of expediency often betray-them.

Jan 1, 1986

The Karangahake gold-silver deposit is located 11 km west of Waihi in the southern part of the Hauraki Goldfield. Historically it was the second largest bullion producer in the goldfield with a past production (1882 - 1944) of 126.712 tonnes of gold-silver bullion (Au:Ag ratio of 1:3.3) from 1 142 315 tonnes of ore grading 27.4 g/tonne gold equivalents.

Jan 1, 1987

The Kingsgate molybdenite pipes are considered on petrochemical data and field occurrence to be, possibly, epi-magmatic plutonic offshoots grading into hydrothermal bodies. There is reason to believe that the ore is derived from a highly acid granite of type similar to that of the tin bearing areas of northern New England. The mineralogy, microtextures and paragenesis of the ore are discussed.INTRODUCTIONThe Kingsgate Mining Field is situated in steep, heavily timbered terrain 18 miles E.N.E. of Glen Innes and 430 miles north of Sydney. Bismuth and molybdenum ores were discovered at Kingsgate (Yarrow Creek) in 1877. Subsequently some 50 pipes were developed yielding tonnages which at the peak of operations, 1905 to 1920, rivalled production from the rich deposits of northern Queensland.Attempts to revive the field have been made periodically and small parcels of ore have been forthcoming.' During World War II demand for piezioelectric quartz again focussed attention on Kingsgate but twinning and other imperfections of the quartz prevented all but a minor exploitation of the otherwise noteworthy crystals of this locality.There is reason to believe that the ore at Kingsgate is not exhausted through exploration and mining costs would probably be high due to the capricious nature of the pipes and to the irregular distribution of rich ore shoots within them.

Jan 1, 1962

By Kobayashi M, Kametani H

Particles of nickel flash furnace malle (45 per cent i) were oxidized in a dropping-particle furnace. The particles melted and the molten drops simulated those produced by the atomization of molten matte. The partly oxidized droplets were quenched and then reacted with silica flux to form high-grade matte (70 per cent i) and a fayalite slag. This paper describes the experimental equipment and deals with chemical aspects of the investigation such as volatile impurity distribution and thermodynamic considerations. The overall behaviour of minor elements such as Cu, Co, As and Pb was similar to that observed in conventional converting.

Jan 1, 1986

By M Dunglison, P M. Cameron

Simultaneous mass-balancing of a mineral processing flow sheet results in adjustments to each data point that reflects the accuracy and precision across the full set of data. In this way, all the good work that goes into designing the sampling and analysis protocol for each sample point is leveraged in order to produce a æbetterÆ set of balanced numbers for every sample point in the circuit. Few operating plants employ whole of circuit balancing techniques to produce reported operating results. This situation is changing with the application of mass balancing technology which utilises redundant data for production accounting and metal reconciliation from product to ore source across multiple phases and multiple time periods. Mine and plant data can now generate credible information to improve productivity. Mine and plant personnel can now use consistent data sets for review and planning. Decisions based on balanced data can be made quicker and with increased confidence.

Jan 1, 2005

By Worner H. K

Education has always been a topic to rouse the interest of mining and metallurgical engineers, but the recent activities of the Education Committee of the Australasian Institute of Mining and Metallurgy 1, 2, together with the moves throughout the Commonwealth to extend the field of technological education, have made the subject a very live one at the present time. The authors have felt it would be appropriate that on the occasion of the First Ordinary Meeting for 1950, in Victoria, some contribution should be forthcoming concerning the history, present status and possible future trends of mining and metallurgical education in this State. As for the past, the time approaches when there will be none having personal recollections of the beginning of Victorian mining schools or of the men who started them. As for the future, it is obvious that rapidly expanding metal-producing and metalconsuming industries will demand a greater output of competent graduates and diplomates. The era immediately ahead seems to be bristling with opportunities, but mining educators need to temper their enthusiasm for various policies and programmes with the realisation that they are helping to train men who will be leaders 15-20 years hence when the problems of industry and trials of life generally may be very different from what they are to-day.

Jan 1, 1950

By Grey CA

Any economic evaluation of a lead-zinc mining project requires the estimation of net revenue per tonne of concentrate at the "mine gate". The value at the mine gate equals the Net Smelter Return minus all realisation costs. The paper develops a simple predictive model for Net Smelter Return based on metal prices.

Jan 1, 1990

By D Craw

Formation of gold-bearing veins in Otago Schist was intimately linked to the structural evolution of the schist belt. The currently-exploited Macraes gold deposit formed in a regional scale shear zone during latemetamorphic uplift of the schist belt. Further exploration for this type of deposit will be facilitated by an increased understanding of the late-metamorphic structural evolution of the schist belt. To this end, a three-dimensional cross section through the Otago Schist has been drawn using structural data gathered at outcrops in a 20 - 40 km wide transect across central Otago. This is the first continuous detailed structural section to be drawn through the belt. The section spans an area from Textural Zone 1 metagreywacke of the Torlesse terrane in the northeast through TZ 4 schist in the central region and across the Caples-Torlesse boundary to Textural Zone 3 schist of the Caples terrane in the southwest. Two different late-metamorphic structural generations are identified in this section: the long-recognised Manorburn Generation, and a new æPoolburn GenerationÆ. The location of the Caples-Torlesse boundary has been refined on this transect by field mapping combined with whole rock geochemistry.

Jan 1, 2001

By P Bartlett, K Naidoo

Premier Diamond Mine is planning a new, mechanised, block cave, with a production level approximately 1000 m below surface. A high degree of tunnel damage is expected, due to stress and the relatively low in situ strength of kimberlite. An evaluation of the timing of tunnel excavation, tunnel size and spacing has been carried out to define critical parameters for planning layouts and development schedules. Extensive use has been made of three-dimensional FLAC3D numerical models, calibrated against known rock mass behaviour at 650 m depth, to examine the influence of undercut advance on production level excavations. These were able to represent the effect of stress rotation on tunnels during undercut advance and the effect of an inclined undercut. The analysis has provided guidelines that are possibly applicable to any deep block cave layout. The choice of drawpoint layout is of considerably less significance than the proportion of ground extracted on the production level elevation prior to advancing the undercut. The analysis shows that damage to production development will be potentially severe if it is all excavated prior to advancing the undercut, or is mined directly beneath the undercut face. The development of the main production tunnels alone ahead of the undercut may be feasible, but no breakaways should be put in as they appear to trigger a rapid increase in the severity of damage. The optimal sequence is when all production tunnels are developed at least 10 m in plan behind the undercut, where the induced peak field stress is less than 20 MPa and a maximum support pressure of 100 to 500 kN/m2 is require to contain movement. The assessment showed that the conditions are not significantly improved by increasing drawpoint spacing from 15 m to 18 m. The vertical spacing between the undercut and production level beneath is investigated. Provided production level development is carried out beneath the undercut, there would appear to be little benefit in increasing the vertical spacing between the undercut and production level beyond the current 15 m to 18 m.

Jan 1, 2000

THE area dealt with in this paper is included within a radius of about 3 miles of the Poimena township. Several thousand tons of tin have been won from this field, and probably £200,000 spent in exploiting it.PREVIOUS LITERATUREThe field has been reported on by Government geologists on four occasions and several ,articles on it have appeared in the mining journals. The work done by Government geologists is summarized below:-"Report on the Blue Tier Tin Mining District and its Tin Deposits", 1886.Speaking of the tin-ore occurrences, this paper states:-"In the primary granite the lodes of tin ore occur, also dykes and belts of more recently obtruded porphyries. The really valuable metalliferous deposits may be classified as follows :-1. Lodes (of which the Lottah mine is typical).2. Dykes- (a) Indurated or hard (as shown by the formations at the Anchor and Cream Creek mines). (b) Soft (eg Hayley's Lease).

Jan 1, 1912

The Mineralogical Researches of Gold Ores and Technological Products at Operating Factory in Olympiada Mine (Russia)

Sep 13, 2010

By A Datar, D Mulligan

The extractive phase of broad-scale mining can have major impacts on landscapes and associated ecosystems. Post-mining ecological rehabilitation typically starts with reconstructing topography. A fairly common industry practice has been to use landform elements such as plateaus, terraces, and gentle slopes for stabilisation purposes. However, this approach can lead to the generation of fairly uniform landforms that do not necessarily reflect natural ecosystems. Previous research in undisturbed and agricultural landscapes shows that ecological attributes and diversity in microclimates is positively correlated with landform heterogeneity. An objective of this study was to investigate if those findings are still valid in post-mining rehabilitating landscapes on North Stradbroke Island, Queensland, Australia. We investigated the relationship between landform heterogeneity and status of ecological recovery. The landform heterogeneity is measured through variance in three landform characteristics (relief, slope, aspect) using remote-sensing data and the status of ecological recovery is represented by ecological indicators measured through field surveys. The results indicate strong correlations between landform heterogeneity indices and native vegetation species richness with sensitivity to the spatial scale of investigation. It is recognised that climate, substrate and rehabilitation practices act as primary drivers of rehabilitation success. However, the results indicate that, in some examples, landform heterogeneity (heterogeneity in relief and slope angles) contributes up to 30 to 50?per?cent of the variance in native vegetation species richness. While the primary drivers of ecological recovery are difficult to control over extensive areas and extended time periods, landform heterogeneity provides a tool to indirectly control the micro-environmental parameters to improve ecological recovery. Reducing the uncertainties in the choice of ecological and landform indices and the degree of landform heterogeneity suitable for particular rehabilitating landscapes would be site specific. The introduction of desired landform heterogeneity may provide a very effective tool for significant improvement in ecological rehabilitation across broad-scale post-mine landscapes, an outcome of benefit to industry, government and local communities.CITATION:Datar, A and Mulligan,?D,?2014. Do we need to change the way we set up the stage?, in Proceedings Life-of-Mine 2014 , pp 29–46 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By B Mobilio, M Secheny, J Rachocki, G B. Sharrock, A Jäger, J L. Lett, I Brunton, G W. Capes

Establishment of the Cadia East Panel Cave Stage One (PC1S1) commenced with the firing of the first bell in early 2011. Production began with the completion of the undercut in May 2014. PC1S1 used a post-undercut composed of 114 drawbells covering a footprint area of 73 438 m². The extraction level is located at a depth of 1200 m below the surface and is based on a 32 × 20 m El Teniente layout. Cave establishment required the construction of multiple conveyor drifts, a large-capacity jaw-gyratory crusher and ancillary ventilation and pumping infrastructure. Preconditioning via hydraulic fracturing and blasting was implemented at various locations of the cave block height. This paper presents an overview of the key learnings from the commencement of undercutting to surface breakthrough, including rock mass classification and modelling, stress measurements, preconditioning, numerical modelling and cave monitoring.CITATION:Lett, J L, Brunton, I, Capes, G W, Jäger, A, Mobilio, B, Rachocki, J, Sharrock, G B and Secheny, M, 2016. Undercutting to surface breakthrough – Cadia East panel cave (stage 1), in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 65–82 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

This paper gives an overview of the difficulties associated with determining the strength of hard rock pillars. Although a number of pillar design tools are available, pillar collapses still occur. Recent examples of large scale pillar collapses in South Africa were caused by weak partings which traversed the pillars. Currently two different methods to determine the strength of pillars are used namely, empirical equations derived from the back analyses of failed and stable cases and numerical modelling tools with an appropriate failure criteria. Both techniques have their limitations and additional work is required to obtain a better understanding of pillar strength. Empirical methods are popular and easy to use, but care should be exercise that the results are not extrapolated beyond the range of the data which were used to derive them. An example is the Hedley and Grant formula (derived for the Canadian uranium mines) that has been used for many years in the South African platinum and chrome mines (albeit with some adaptation of the K-value) to design the pillar layouts. Very few collapses have nevertheless been reported and it might even be too conservative an assumption of pillar strength in these mines. As an alternative, some engineers strongly advocate the use of numerical techniques to determine pillar strength. A close examination unfortunately reveals that these techniques also rely on many flawed assumptions. An area where numerical modelling is invaluable, however, is to study specific pillar failure mechanisms, such as the influence of weak partings on pillar strength. In conclusion, it appears that neither empirical techniques nor numerical modelling currently provide a solid basis to conduct pillar design. It is therefore recommended that both these techniques be utilised when confronted with a pillar design to obtain the best possible insight into the problem.

Nov 25, 2010

By L J. Ingle, K L. McPhee, A G. Hunt

Iron Road Limited (IRD) is currently developing the Central Eyre Iron Project (CEIP) at Warramboo on the Eyre Peninsula, South Australia. The project consists of a 30 year open pit mine, magnetite processing facilities, standard-gauge railway and deep water, Cape class capable port. Major South Australian government approvals have been received and funding arrangements confirmed.The 4.5 Bt Mineral Resource (3.7 Bt Ore Reserve), the largest in Australia and among the largest globally, is to be mined to produce 24 Mt/a high-grade, 67 per cent Fe, magnetite concentrate. This in-demand, premium product has a P80 of ~100 µm, suitable for both direct sinter feed and an additive in pelletising.The extensively drilled, homogeneous orebody is unique in both geology and mineralogy; only averaging 15 per cent Fe yet coarse-grained with almost negligible phosphorus and sulfur content. This has allowed significant opportunities to tailor the mining method to the orebody, utilising both optimised blasting as first stage comminution, as well as in-pit crushing and conveying (IPCC) to reduce the heavy haulage diesel fleet and optimise the pit shell.Approximately 1 Mt/d of total material, ore and waste, is required to be moved from the pit daily, introducing materials handling challenges, overcome by a flexible IPCC set-up, multiple overland conveyors and an exacting mine plan. Non-conventional waste and tailings storage is utilised to allow for significant water savings, progressive rehabilitation and minimisation of land impact.The processing facilities utilise both the magnetic and density properties of the magnetite to beneficiate the ore. The coarse-grained nature of the ore is exploited to minimise comminution yet still liberate a high quality product. Utilisation of modular construction methods allows risk reduction during construction and reduced pumping requirements during operation.This paper highlights the uniqueness of the CEIP, with focus on the mineralisation of the orebody, and the beneficial impacts this has on both the proposed mining method and processing. Magnetite mining is not new and IRD has used the learnings of others, and input from various vendors and industry experts, utilising knowledge and expertise to engineer an innovative, yet supported, project design.CITATION:McPhee, K L, Hunt, A G and Ingle, L J, 2017. The Central Eyre Iron Project – developing a new iron ore mine in a challenging climate, in Proceedings Iron Ore 2017, pp 613–620 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By D Brown, Z Tabor

Projects must be flexible to account for the rapid development of new technologies and changing stakeholder expectations. Coupled with calls for bleeding-edge solutions, customers, shareholders, and regulators demand robust, safe products and systems-of-systems. Developing and integrating these solutions is becoming increasingly complex and maintaining the flexibility required to ‘pivot’ to effective solutions can be a serious challenge. The necessary flexibility is fundamental to the Agile ethos, and this family of methodologies therefore offers a potential solution to this challenge (Beedle et al, 2001). These have traditionally been delivered with systems engineering applied through a Waterfall methodology. Agile Systems Engineering combines both approaches and presents a means to achieve these goals without compromising flexibility, quality or safety. A robust methodology for the application of Agile Systems Engineering is required to enhance practical outcomes and reduce risk for real-world mining projects.

Sep 1, 2024