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By J Manuel, A Trudu

Regulations on the emission of particulates from sinter plant stacks are becoming increasingly stringent and reducing these emissions by improving gas cleaning systems is a significant cost to the sinter plants. This paper describes an investigation into the emission of particulate matter from an iron ore sinter bed during the sintering of a Japanese Steel Mill (JSM) style ore blend in a 300 mm diameter pot grate test facility. Several techniques were trialled to determine a reliable method to sample the quantity of dust emitted and determine the mechanism of dust emission from the sinter bed. The nature of the dust was also examined using chemical and size analysis as well as optical and scanning electron microscopy. The paper discusses the techniques used to carry out the program as well as results on dust loading measured during sintering and the nature of the dust captured.

Jan 1, 2002

In October 1993 it was decided to undertake the fourth phase of mining at Big Bell. This decision followed the exhaustion of open pit reserves in January 1993. Two stages of mining were proposed for the new underground mine. The initial stage would mine the remnant ore, consisting of the rib and crown pillars and lower grade ore on the hangingwall and footwall side of the old open stopes, which were mined from the 1930s to 1950s. Most of the old open stopes were backfilled with either deslimed mill tailings or development mullock, both of which were economic to recover. However, the mineable ore from this resource was difficult to evaluate. The second stage focused on mining ore outside the remnant areas and was initially proposed as a Core and Shell method under a caving hangingwall. This method has since been superseded with sublevel caving, in part due to the very high and deviatoric stress conditions encountered at Big Bell and the relatively long mining cycle required for open stoping. The problems and challenges discussed in this paper will cover the identification of remnant ore reserves, dewatering the old workings, and remnant mining.

Jan 1, 1998

By C J. Moran

Given that the mining industry is committed to sustainable development principles and that Australia is experiencing changes to the regulatory environment that aim to modernise the water sector and encourage adoption of consistent approaches, there is a well defined need for the Australian minerals industry to develop a water accounting framework. This requires: key terms and definitions for water metrics for use in the Australian minerals industry that is consistent with the wider water sector, a suite of metrics representing key components of an operationÆs water balance, a calculation method for some of the metrics, and a reporting protocol. This paper presents the methodology that was used to derive these four components. Existing accounting frameworks were reviewed and key terms and definitions that were consistent with current requirements were proposed. A calculation methodology was developed to obtain some of the key indicators and variables that cannot be easily measured directly (water loss through evaporation is an example). The adopted terms and definitions dictated model development, with the conclusion that a systems approach was the most effective calculation process. To test the proposed definitions and calculation methodology, values for water metrics were derived for eight sites. The proposed framework and definitions could deal with the specific situations selected as case studies. The associated calculation methodology produced complete accounts at various levels. Some elements of the accounts could be directly checked against available data and simulations. The framework captured well variations in the reuse efficiencies; reuse efficiency could even vary for similar processes. It is concluded that this preliminary accounting framework provides a consistent language and metrics for quantifying and communicating water management, both at the intersection of the site with the surrounding landscape (through detailed reporting of site inputs and outputs) and within operational activities. Using this consistent framework for quantifying and documenting water use within an operation will provide a platform for compiling and comparing minerals industry water use with other sectors. This may support benchmarking activities within regions or companies and help demonstrate leadership amongst water users in water resource stewardship. The approach presented here is applicable to a wide variety of mining and processing activities, and biophysical environments, and can be adopted as the first step towards developing national water accounts for the Australian Minerals Industry.

Jan 1, 2009

By I M. Platten

Narrow reef gold deposits are generally less than 4 m in width and relatively complex geological phenomena. They often display variable geometry, attitude, continuity and internal architecture. Economic grades are mostly restricted to specific structural domain(s) and localised within discrete ore shoots that have a nuggety internal grade distribution. On account of the often extended history of geological events, the specific factors localising gold-rich domains are likely to be unique to a particular mine or even reef. These features lead to a high resource risk and require careful management during both evaluation and mining. The gross form, location and global continuity of gold reefs can generally be determined from surface diamond drilling leading to the definition of Inferred Mineral Resources. It is likely that for the definition of Indicated and Measured Mineral Resources underground development and/or close- spaced diamond drilling will be required. Understanding geometry and continuity permits the resource to be more effectively managed, lowering risk/uncertainty. This in turn will allow for well-informed financial and operational decisions. Most importantly, project expectations and milestones can be set at achievable levels.

Jan 1, 2008

The mostly submerged New Zealand sub-continent has a complex geological history and an active oceanographic regime that provides opportunities and challenges for offshore mineral exploration. Known deposits include polymetallic Fe-Mn nodules and crusts, polymetallic massive sulfides, phosphatic nodules, titanomagnetitie ironsands and placer gold deposits. Currently exploration interest is high with some 3.5 per cent of the EEZ under prospecting permit or application.   Article 76 of the UNCLOS convention allows coastal states to have sovereign rights over areas of the seafloor that are natural prolongations of the landmass that constitute submerged parts of the continental margin as extended continental shelf. New Zealand has substantial areas of elevated ridges and plateaux beyond the 200 M EEZ that form extended continental shelf. New Zealand has nearly completed a ten year, $44.4 M programme to define its outer extended continental shelf. New Zealand will lodge its outer limits of the extended continental shelf with the UN-appointed Commission on the Limits of the Continental Shelf in 2006, which if accepted, will enclose ~1.8 million km2 beyond the existing EEZ. Ocean Survey 20/20 is a follow-on marine mapping programme to underpin resource exploration and environmental management of the EEZ and extended continental shelf.

Jan 1, 2005

By P Minkkinen

"Pierre Gy showed in his early works that the results in estimating the variance of the mean value of continuous lots depends on sampling mode (random, stratified or systematic), except in the theoretical case that the measurand is randomly distributed in the lot. The experimental variance estimate calculated from samples taken from the lot is independent of sampling mode but depends on sample size and the type of the lot heterogeneity. Variography can be used to estimate the variance of the lot mean for different sampling modes.Gy also defined weighting error, which is made if a simple average is calculated from the assays of samples taken from a continuous object (eg from a process stream) where the flow rate varies with time and is correlated with the concentration of the analyte in the stream.The effect on sampling uncertainty of the three sampling modes and their interaction with the following factors in estimating the uncertainty of the mean concentration is studied using simulated lots, and lots having heterogeneity patterns similar to those of real data sets, including the effect of: the type of heterogeneity (random, grading and clustered heterogeneity patterns) increment size and number employing composite sampling weighting error. CITATION:Minkkinen, P, 2017. Dependence of the variance of lot average on the sampling mode and heterogeneity type of the lot, in Proceedings Eighth World Conference on Sampling and Blending, pp 319–330 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

May 9, 2017

By A Radici, S Russell

The Dampier Port Upgrade was completed in 2007 and is the largest project in Rio Tinto Iron Ore's expansion program. The project doubled Dampier Port's iron ore shipping capacity over a five year period. Sinclair Knight Merz (SKM) was appointed by Rio Tinto as the Engineering, Procurement and Construction Management (EPCM) contractor to manage Phase A and Phase B of the Dampier Port Upgrade. The aim of the project was to increase the Dampier Port capacity from 74 to 140 million tonnes per annum (Mt/a). This increase in shipping capacity tripled the capacity of the Parker Point facility from 34 to 94 Mt/a, whilst the East Intercourse Island facility increased from 40 to 46 Mt/a. The Dampier port remained fully operational throughout construction and achieved record yearly export tonnages over the period of the project. The $US1.4B project was completed ahead of schedule, on budget and with an outstanding safety record. Significantly the project team set an industry benchmark by achieving five million man-hours Lost Time Injury (LTI) free. The project has been recognised by the Engineers Australia 2008 Western Australian Engineering Excellence awards as category winner in resources and the overall winner in WA, and went on to win a National Engineering Excellence award. This paper provides an overview of the EPCM project management and an insight into some of the key drivers that have delivered this outstanding project.

Jan 1, 2009

By R Castedo, P Segarra, L M. López, J A. Sanchidrián, A P. Santos

The cylinder test allows us to determine the expansion of a copper cylinder by the detonation of an explosive charge inside. This test, originally designed for military explosives, has been adapted for industrial explosives with non-ideal behaviour. From data obtained with this test and known physical relationships, an analytical procedure has been developed to calculate the Jones-Wilkins-Lee (JWL) equation of state parameters for five ammonium nitrate/fuel oil (ANFO) and six emulsion-type explosives. A new radial wall expansion function is proposed considering a non-zero initial velocity with the consequent positive Gurney energy at unit relative volume. A set of equations is established to determine the JWL parameters, three of them obtained at the Chapman-Jouguet (CJ) point and the other three at different relative volumes. These equations, along with some constraints to ensure a physically sound solution, are solved for the JWL parameters by a non-linear least squares scheme. A 2D Lagrangian axisymmetric finite elements (FE) numerical model is developed for each tested explosive to validate the analytical results, in terms of expansion histories, with good agreement. This confirms that the set of conditions, constraints on the parameters and least squares calculation used constitute a robust methodology that fully captures the physics of the detonation products expansion involved in the cylinder test.CITATION:Castedo, R, Sanchidrián, J A, López, L M, Segarra, P and Santos, A P, 2015. Jones-Wilkins-Lee parameters for civil explosives, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 57–64 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By J D. Bryant

The Ernest Henry Copper-Gold mine, the third largest copper deposit in Australia, is located 35 km NE of Cloncurry in the Mt Isa-Cloncurry mineral district of NW Queensland. Ernest Henry Mining Pty Ltd (EHM), a wholly owned subsidiary of Xstrata Copper Australia, operates the mine. Approximately 10.2 Mt of ore grading 1.12 per cent Cu and 0.56 g/t Au were processed during the 2001 - 2002 financial year. The Ernest Henry plant produces copper-gold concentrate, which is trucked to Mt Isa for smelting. The Ernest Henry deposit is a member of the diverse Fe-oxide-(Cu-Au) class of deposits. The orebody is hosted within a sequence of moderately SSE-dipping, intensely altered Paleoproterozoic intermediate metavolcanic and metasedimentary rocks. Copper (chalcopyrite)-gold mineralisation occurs mainly within the magnetite-biotite-calcite ¦ pyrite matrix of a 250 m + 300 m pipe-like breccia body. The breccia pipe comprises two anastomosing lenses separated by a lower grade, clast-supported breccia zone. Several anastomosing brittle faults affect the macro-geometry of the orebody. Copper grade is proportional to the degree of matrix support in the breccia. The July 2002 Ore Reserve was 88.7 Mt @ 1.0 per cent Cu and 0.5 g/t Au. Resource estimation at Ernest Henry is based on a large database of predominantly diamond drill hole information. Drill spacing is typically 50 m + 50 m. Ordinary kriging is used to estimate Cu, Au, SG and IST (oxidation indicator) into model parent cells of dimension 20 m E + 20 m N + 16 m RL. The block model is comprised of five geological-geochemical domains represented by 3D wireframe surfaces. Zonal control, where samples and blocks are assigned the same domain number, is used to control grade estimation. The geometry of the domains defines hard grade boundaries across strike and soft boundaries along strike A Deep Drilling Project was initiated in August 2002 with the initial aim of testing the down-plunge extension of the orebody to a vertical depth of over 1 km. The encouraging intersections to date have resulted in a significant increase in the mineÆs open pit Mineral Resource together with the identification of an underground Mineral Resource. Added benefits of the project included an expanded and updated geological legend and an improved understanding of the host geological sequence.

Jan 1, 2003

The South American mining community leads the world in recognition and adoption of the latest grinding mill relining technologies. Clearly this region has recognised the benefits of improved relining performance as a defence against the Global Economic Crisis. Five of the six RUSSELL TWIN 8 Mill Relining Systems, ordered to date, are either operating or being manufactured for South American mine sites. The sixth is for Sino IronÆs Cape Preston Project in Western Australia. This paradigm shift, towards very short relining times, aims at displacing mill relining activities from the critical path of concentrator maintenance shutdown schedules. The first uses of the RUSSELL TWIN 8 Mill Relining System have seen some of the highest semi-autogenous grinding (SAG) mill new liner placement rates ever observed by Russell Mineral Equipment (RME), as would be expected with two, independent Machines working simultaneously in the one mill. The liner replacement rate, averaged over the whole reline is good (27 per cent improvement over single Machine System in the same mill) but short of full potential. This modest result can be attributed to reline crews unfamiliarity with RUSSELL TWIN 8 System operation. This paper compares a sample of conventional (single machine) RME Mill Relining System performance data with one ædouble headÆ mill liner handler by others. Early performance of EscondidaÆs new RUSSELL TWIN 8 System performance is then compared with recent single machine data from Escondida, immediately prior to RUSSELL TWIN 8 commissioning. RME and Escondida look to constantly improving RUSSELL TWIN 8 System performance as full operational familiarity is achieved. The preparation of this paper revealed a need to develop a global industry standard for mill relining data collection. A web based platform to develop data collection templates is also discussed in Appendix 1.

Jan 1, 2009

By T Sirinawin, R H. Murfitt, W Shywolup

The Bong Mieu Project lies within the Pre-Palaeozoic Kontum Craton near the southern margin of the regional Phuoc Son û Tam Ky Suture. The Suture and accompanying Truongson Fold Belt of Indosinian age host significant gold and base-metal bearing districts including OlympusÆ other project at Phuoc Son to the west of Bong Mieu and OxianaÆs Sepon project in Laos. The Bong Mieu Project is located some 90 km south of Da Nang and some 30 km south-west of Tam Ky, the provincial capital of Quang Nam province in central Vietnam. The project area is covered by an Investment Licence of some 30 km2 which was granted in 1991 and a mining permit of some 365 ha granted in 1992. Several mesothermal, gold-silver deposits with assigned resources are present on the property. Deposits with assigned resources contain some 615 000 ounces of gold in situ. These are at Ho Gan and Ho Ray which are potentially exploitable by open-pit mining and Nui Kem which is potentially exploitable by underground mining. Newly discovered extensions to the known deposits at Ho Gan, Ho Ray and Nui Kem, and several other new prospects, are currently being investigated by drilling. The Ho Gan mineralisation is of mesothermal, shear and shear breccia quartz vein, as well as intrusive breccia hosted style. Nui Kem mineralisation is of mesothermal, shear and shear breccia quartz vein style. The Ho Ray mineralisation is of skarn (gold-bismuth-tungsten) and lesser quartz vein style. The deposits straddle and flank the east-west trending Bong Mieu Anticline which trends through the central portion of the Investment Licence. In this paper the geology of the deposits, details of resources, results of recent exploration on the Investment Licence and recent engineering and mining studies at Ho Gan are briefly reviewed.

Jan 1, 2004

By I F. Wood

Planning for flooding and assessment of flood impacts are important requirements for mining projects, as they are also for other types of development. With more intense development and concern from the community, supported by government regulatory requirements, assessment of flood concerns and impacts has become of increasing importance. To ensure that flooding issues are fully understood and results presented in an appropriate format, advanced hydraulic analysis procedures have been developed and are beginning to be applied. These procedures must be rigorous in an engineering context but the results must also be readily understood by the community and government agencies. Advanced two-dimensional hydraulic modelling is becoming accepted as an important means of assessing flooding issues for mining projects. With presentation of results from hydraulic models with Geographic Information Systems (GIS), flood impacts can be analysed rigorously and presented clearly. This paper discusses the application of advanced hydraulic modelling in the planning and impact assessment of a major mining project located on a floodplain where there is extensive inundation. The analysis provides for both input to the planning of the project and for detailed assessment of potential impacts. This case study illustrates some important aspects of the application of hydraulic modelling using a two-dimensional modelling to a critical flood design.

Jan 1, 2003

The New Zealand Minerals Industry Association was incorporated as the NZ Mineral Exploration Association in 1982, with a membership that consisted of the gold exploration companies then active in New Zealand . As its membership broadened, it changed its name to the Mining and Exploration Association in 1994, and more recently the Minerals Industry Association. It is a non-profit-making incorporated society relying on voluntary membership, and is not funded by industry levies.   It has employed a full time executive director since 1988 when Robyn Ross was appointed, followed by John Pfahlert (1991 - 1996) and now with Doug Gordon managing the Association.   The Association is one of a number of organisations that represent the mining industry in New Zealand. Others include the Coal Association of NZ (CANZ), the Aggregate and Quarry Association (AQA), The West Coast Commercial Gold Miners Association and Minerals West Coast.   NZMIA membership comprises the main exploration and mining companies that account for over 80 per cent of New Zealand Æs mine output, and nearly all of its exploration investment. Its membership has expanded from gold exploration to encompass exploration and mining companies active in coal, gold, aggregates and industrial minerals.   The Association has developed a National Minerals Strategy that determines its priorities, implemented via a Minerals Industry Advisory Committee. This group was established six years ago to advise the Associate Minister of Energy on issues relating to the long term development of the minerals sector in New Zealand.

Jan 1, 2006

The .subject of this paper is to briefly outline various methods of stockpiling and reclaiming, and the use of different types of bucketwheel re- claimers and stackers in these operations. The paper examines briefly the different types of bucketwheel equipment, their operations and relates them to different stockpile layouts, giving examples of their application in Australia.

Jan 1, 1973

By J Finlay, P Betts, D Milton, H Williams

The aim of this paper is to present an innovative method to help delineate potential target volumes for haematite-goethite mineralisation as opposed to more magnetic ores. This is achieved through interpretation and modelling (2.5D and 3D inversions) of ground magnetics and gravity surveys over the Koolanooka South prospect in Western Australia. The targets are assumed to be dense and weakly magnetic and hosted within banded iron formation (BIF) horizons. Geophysical interpretation (2D map) was performed using a variety of processed magnetic and gravity images (Betts et al, 2007) to determine the distribution of lithologies, to understand the structural architecture and to map out any anomalous areas of excess density (possibly indicating goethite alteration). The created geological map is used to build geological cross-sections (geometrically consistent) that were modelled (in 2.5 D) against both potential field datasets. The crosssections are consequently used as the framework to build a 3D geological model. The model defines 3D volumes of rocks including several BIF horizons. The distribution of densities and magnetic susceptibilities of the BIFs is inverted within the GOCAD«-VPmg environment to reduce the misfit between the response of the model and the observed gravity and magnetics. By combining the results of both petrophysical property distribution it is possible to map out (using classical GIS type queries in 3D) volumes of higher density and lower magnetic susceptibility.

Jan 1, 2009

By J Bartlett, P Quigley

Historical research has played a significant role in the rebirth of the Bendigo Goldfield. The historical research undertaken by the company has been directed to specific areas such as verifying the total gold production of the field, the gold production from defined blocks on each of the major anticlines, the extent of workings of each mine which exceeded 200 m depth, the size and style of reefs mined in each shaft and also within specific domains of the field. Application of this data has assisted in the determination of possible dimensions of different reef styles and the location of mineralisation within each reef system. Description of grade variation, percentage of quartz and the amount and species of accessory sulphide minerals, as well as early geotechnical observations accompanying stoping methodologies, provides valuable analogues for reef structure being defined in the current program. Historical information on shafts on the two anticlines the company is exploring has allowed the postulation and recognition of repetition of reef development within the same stratigraphy in the hinge zones of the adjacent folds. The similarities of mineralisation styles across the field within both specific lithological units and structural setting has had important implications in respect to exploration drill targeting and the estimation of grade and tonnes.

Jan 1, 2003

By W A. Peppin, D N. Riley, N W. Schulenburg

In June 2008, a joint airborne collection using hyperpspectral systems was tested on a single Twin Otter aircraft. This experiment was designed to incorporate two airborne hyperspectral sensors for geological and environmental projects. Mineral exploration and environmental impact statements are two areas where full spectrum hyperspectral data can document the mineralogy at the surface prior to mining operations. Many previous hyperspectral remote sensing collections were collected on a single aircraft with a single sensor. Mineral mapping using hyperspectral sensors that measure in complimentary regions of the electromagnetic spectrum is cost effective as it allows for the mapping of clays, sulfates, carbonates, feldspars, quartz, garnets and many other minerals. This report describes the experiment using the following two hyperspectral sensors: ProspecTIR, a visible near and shortwave infrared (VNIR-SWIR) sensor with 356 channels and spectral range of 0.4 to 2.5 ¦m, along with a spatially enhanced broadband array spectrograph system (SEBASS), a midwave and longwave infrared (MWIR-LWIR) sensor with 128 channels from 2.5 to 5.3 ¦m and 128 channels from 7.6 to 13.5 ¦m. SpecTIRÆs ProspecTIR system and The Aerospace CorporationÆs Spatially Enhanced Broadband Array Spectrograph System (SEBASS) are pushbroom sensors, have high signal to noise ratios, have similar swath widths and instantaneous fields of view. Examples of data collection experiment will be shown with a focus on mineral/lithologic identification and mapping along with environmental assessment in the western United States. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By L E. Krause

This paper discusses the considerations for optimum maintenance of critical ore handling infrastructure in order to minimise the cost to the business of maintenance periods. As maintenance periods are a direct interruption to production, time is of the essence and careful management of shutdown periods is essential. The ore pass systems currently in use at Xstrata Copper û Mount Isa Copper Operations are up to 30 years old and have had significant wear over the years. The maintenance of these passes and their brows and chutes in a production situation is a challenge as it can potentially expose personnel to high risk situations in addition to the production interruptions. Some alternatives for mitigating the risk of working in ore passes including plugging and ballooning are described. Criteria are included for selecting a method for the safe entry into a given ore pass. Experience in adapting the method of ore pass plugs and some lessons learnt in the process are also discussed.

Jan 1, 2005

One of primary causes of poor blast performance is the improper relief of explosive energy. Under or over-confined blasts modify the explosiveÆs path of least resistance, which changes where and when the explosive energy is applied resulting in less than optimum blast performance. During the research for this paper the overbreak characteristics of five full-scale blasts were quantified using high speed cinematography and borehole cameras. The effectiveness of various overbreak control methods was also evaluated to guide design refinement. The results of this research along with general recommendations for reducing excessive damage are included with this paper.

Jan 1, 1999

By Lynce AJ

A method has been developed for the prediction 'of 'the- . performance of a multi-stage grinding=cyclone classification circuit of any degree of complexity on any ore for a wide range `of operating conditions, The-.method involves ;the. s` inu ation b'f the circuit on a digital computer by means of. matheinatical' models ":bf the"' individual units:, the. development of which is- also discussed'., At present, in order to establish 'the!'" charac'teristtics of they ¦ore- and the machines. in mathematical terms;. it is necessary to know'the performance of a , simpl,.e. ; system on tri.e ore - for! one known ,,feed rate and.fe.ed s,l-zing, analysis. ' ,Fiiither work on :the- separate identification 'of the terms defining the characteristics of the ore and the machines may permit the method to be, applied directly to the cj.4ta,derived from small scale tests on ores,

Jan 1, 1964