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By J Nortier, J Dray

There is no single factor that determines the appropriate capacity for a mining project. It is driven by the size of the resource, the capacity of the market, the availability of capital, the availability of power, the availability of water, and a myriad of other considerations. There is also no single solution to the question of how big the project should be. However, to develop a project, the study team needs to select the configuration options that it regards as the best for the project. To be able to make this selection, the study team should consider the range of available options and do so at a level of detail that gives it confidence in the conclusion but does not lead to multiple detailed design exercises. Having considered the range of options, and with a clear definition of the project owner’s objectives and constraints, the work to be carried into feasibility studies can be focused appropriately. This paper discusses the process of completing strategic mine planning to identify project configuration options to assist in the selection of the processing plant throughput rate (Capacity Study) for a large greenfield open pit mine. The processes described in this paper allow for the basis of design to be set for subsequent studies that meets the objectives at a risk profile acceptable to the owner.

Jun 22, 2022

I congratulate The Australasian Institute of Mining and Metallurgy on its decision to hold its Annual Conference here in Western Australia. Western Australia, with its abundant mineral and energy resources, plays a key role in the Australian mining industry... and Western Australia will continue to figure prominently in this vital industry for many years to come. The success of our gold, iron ore, bauxite, mineral sands and other primary industries has enabled Western Australia to contribute significantly to Australia's export revenue and, therefore, to the nation's economic strength. The State's mineral wealth has also provided the impetus for a recent surge in mining related activity, including a dramatic increase in downstream processing of our raw materials. Billions of dollars worth of new project investment is either committed or awaiting final approval - and most of this new investment is a direct result of a healthy and vibrant mining industry. The North West Shelf Project - which has been providing natural gas for homes and industry in Western Australia since 1984 - has also played a key role in stimulating industrial development. The availability of abundant, competitively-priced gas from the North West Shelf has - along with the availability of other raw materials - made Western Australia a more attractive proposition for industrial investment. The company I represent, Woodside Offshore Petroleum, is operator of the North West Shelf Project on behalf of the Project's six Joint Venture Participants - Woodside Petroleum Ltd, BHP Petroleum (North West Shelf) Pty Ltd, BP Developments Australia Ltd, Chevron Asiatic Limited, Japan Australia LNG (MIMI) Pty Ltd and Shell Development (Australia) Proprietary Limited. The theme for this Annual Conference: "Excellence - the key to the continued success of the Australasian mining industry" is appropriate to the North West Shelf Project. The pursuit of excellence has been a hallmark of the Project. The Joint Venture Participants have been conscious of the need for stringent quality control at all stages of development. Procurement and purchasing policies, for instance, have demanded strict adherence by contractors and suppliers to the highest standards and specifications.

Jan 1, 1989

Cleaner Production stands for a proactive and preventive approach to industrial environmental management and aims for process- and/or product-integrated solutions that are both ecologically and economically efficient (æeco-efficiencyÆ). Pioneers in the field were large manufacturing and processing industries in the USA (since the late-1970s), but it took until the early-1990s before Cleaner Production was generally recognised as a valuable approach for large and medium sized enterprises. The application of Cleaner Production in mining and minerals, metals and energy production appears to lag behind other sectors, such as manufacturing and processing. This paper starts with a discussion of the Cleaner Production concept and provides examples of its application from a few selected Australian mining and minerals processing industries. This evidences that Cleaner Production can achieve significant reductions in environmental impact, in terms of reduced waste and emission generation and in terms of conservation of materials, energy and water, while simultaneously reducing operating costs. The paper then investigates a number of key issues pertaining to the implementation of Cleaner Production; ie organisation and management of Cleaner Production activities, effective tools for mastering the Cleaner Production concept as a way of life, and performance measurement.

Jan 1, 2002

By P M. Cepuritis

In hard rock mining, large-scale bulk mining methods such as block or panel caving (BC/PC) and sublevel caving (SLC) typically generate significant surface deformations such as subsidence. Surface deformations need to be considered in the project evaluation and planning stages of cave mines, for example, planning and location of critical underground mine planning infrastructure such as portals, haulage and vent shafts, access roads, or potential damage to existing infrastructure, changes to surface water management, waste dump, stockpile and tailings dam stability, and environmental impacts. Assessing the impact and risks associated with subsidence is a key component in robust mine planning and operations management.

Nov 29, 2022

By B J. Monaghan, R J. Longbottom, D J. Pinson, S J. Chew

Recycling steel plant by-products is a critical issue for achieving both environmental and economic sustainability of integrated steel plants. A key steel plant by-product stream is dust from basic oxygen steelmaking (BOS), which can be recycled back to the BOS vessel as iron units and to aid slag formation. The major limitations for its recycling are zinc and the uncertainty in zinc speciation of the dust. This uncertainty affects the amount of dust recycled and how it interacts with the slag during processing. BOS dust in stockpiles can undergo self-sintering reactions that oxidise the iron-bearing components. As this occurs, zinc (or oxide) may combine with iron oxides to form a zinc-iron spinel solid solution phase. Knowing which zinc-bearing species are present in the BOS dust is a key aspect in understanding and developing an efficient recycling process for the dust. To overcome difficulties associated with phase identification in the BOS dust (both fresh and selfsintered), particularly the magnetite-zinc ferrite spinel solid solution using X-ray diffraction (XRD) / scanning electron microscopy (SEM) / energy dispersive spectroscopy (EDS), high end characterisation tools, transmission electron microscopy (TEM) and Mössbauer spectroscopy, were also used. Such an approach allowed improved phase identification of key zinc- and iron-bearing phases that were not previously resolvable. The zinc in fresh BOS dust was mostly present as extremely fine separate particles of zinc oxide, attached to the iron particles. These extremely fine particles were <10 nm in size. Additionally, a small amount of zinc ferrite was also identified within the sample (most likely contained within a magnetite-zinc ferrite spinel solid solution). However, the zinc in the self-sintered BOS dust, was found to be present entirely in a magnetite-zinc ferrite spinel solid solution. While this spinel phase had been previously identified by XRD, it was not clear that it contained zinc. The Mössbauer results provided definitive evidence of zinc within the spinel phase.

Jun 19, 2024

By E du Plessis, M Rowley, M Fallon, F Golenya, R Swanson, I Robertson

"Check sampling programs were undertaken at Barrick Australia Pacific LimitedÆs Lawlers and Plutonic mine sites in Western Australia. The programs identified that the sampling, sample preparation and assaying protocols required modification to ensure acceptable precision (reproducibility) for each gold mineralisation type. These case studies describe the processes used to identify the: inconsistent precision different types of test work programs that were conducted to quantify the appropriateness for each mineralisation type steps used to modify the protocols.The type of test work conducted included: a duplicate series heterogeneity test for particulate gold mineralisation in the Lawlers gold deposit screen fire assay test work on duplicate subsamples for arsenopyrite associated mineralisation at the Plutonic gold deposit.Each test work program required a detailed scope specifying the sample selection criteria, sample preparation and assaying steps. The aim of the test work flow chart design was to ensure the assay precision between the different particle sizes or duplicate sample pairs could be measured and calculated. In the screen fire test work the true grade of the primary sample was calculated and compared against each subsample.A high quality assay laboratory was utilised for the test work. All samples were fire assayed and the gold grade determined using a gravimetric finish. The assay results were validated and the data was analysed using tables and graphs in spreadsheets. Following data analysis a modified sample preparation and assaying protocol for each mineralisation type was designed for use by the principal assay laboratories. Following implementation of the new protocols, routine check samples were collected during the sample preparation and assaying stages to monitor the performance of the new protocol.CITATION:Fallon, M, Rowley, M, Du Plessis, E, Golenya, F, Robertson, I and Swanson, R, 2012. Confirming the sampling, sample preparation and assaying protocols used at two Yilgarn gold deposits, in Proceedings Sampling 2012, pp 47-62 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 21, 2012

By J Naude

The TauTona (Sotho for Great Lion) Mine near Carletonville, which is one of AngloGold AshantiÆs most profitable operations in South Africa, has started a multi-million dollar expansion project that is expected to extend the operational life of the mine by at least three years. The project will also secure some 1900 jobs for existing workers and contract workers. The $US140 million project entails the development of the orebody to a record depth of almost 4 km underground. It means that TauTona, which already mines gold at the deepest levels in the world, will deepen its mining activities from 3600 m to a new record depth of 3910 m. There is great anticipation about the expansion program, especially because of new technology that will contribute to a safer working environment. It includes a simplified hoisting system that will minimise safety risks in conveyance activities. Due to the unique nature of this project, depth below surface and working through a three-tier shaft system, various innovative measures were incorporated into the planning of the endeavour. Special support equipment was designed to reduce cycle times and enable the crews to install the extensive support, prescribed by the mineÆs rock engineering department, right up to the face before every blast. Both declines dip at 23¦. The personnel/material (P/M) shaft is 4.4 m wide x 3.9 m high. This shaft is unique in that the conveyance will have an onboard driver. The rock shaft is 4.5 m wide x 3.6 m high. Rock will be hoisted with two, ten-tonne overturning skips. In both cases, P/M and rock, the winders were designed for the highest duty cycle, which is encountered during sinking.

Jan 1, 2005

A new plant for grinding limestone was built at the Risdon Works of the Electrolytic Zinc Company of Australasia Limited to meet increasing process demands expected to reach 150 tonne/day of ground limestone. Plant specifications included open- circuit wet grinding, a single ball mill, a feed sizing of minus 6 Tyler mesh, a product sizing of 100 per cent minus 200 and 95 per cent minus 325 Tyler mesh and for the plant to be unmanned during normal running. Main features of plant and equipment are described; grinding performances given, as well as operating experience since commission- ing of the plant in March, 1976.

Jan 1, 1977

By M A. Vinokurova, V M. Mullov

Due to treatment of refractory carbonaceous low-grade gold ores a new technology providing improved precious metal recovery is required. For this reason, a technology including gravity, flotation, recleaning of the flotation concentrate, intensive cyanidation of the gravity concentrate and carbon in leach (CIL)-process for intensive cyanidation tailings and the recleaned concentrate was developed. The proposed technology allows to decrease preg-robbing activities of concentrates treated by subsequent cyanidation. Total gold recovery by the proposed technology from the ore with a head grade of 0.8 g/t was 83.9 per cent. The gold loading onto the activated carbon from CIL process was 6.500 g/t.

Jan 1, 2007

Inadequate understanding and/or assessment of technical and economic risk associated with geological uncertainty are key reasons many mining projects do not achieve forecast profitability. In the last 20 years many new and existing mines have experienced geology related problems, including lower than planned development and production rates, geotechnical/stability issues, unplanned dilution, ore loss, reduced metallurgical performance, environmental management concerns and unbudgeted capital/operating costs. Greater emphasis on the evaluation and communication of uncertainty associated with geological interpretations for feasibility and operations management results in better decision-making. The outcome of better decision-making is more efficient mining yielding enhanced financial returns for the mining industry.

Jan 1, 2009

A new approach to strategic planning, the Life of Business Optimisation System (LOBOS) optimises production systems from the scale of stopes in a single mine to an entire business strategy consisting of multiple mines and products competing for capital and processing capacity. LOBOS has optimised cash flow for a wide variety of operations, including large metalliferous or coal mines and as an aid to high-level strategic business optimisation solution to multi-mine/processing/product complexes. This paper discusses the application of optimisation technology to strategic planning with an emphasis on project evaluation with examples on the application of LOBOS to a variety of recent projects.

Jan 1, 2007

By S Corbel, P J. T Donchak, W Gorczyk

The Hodgkinson Province numerical modelling project aims to develop an improved understanding of the physical conditions that lead to the localisation of goldbearing fluids within known systems and apply this understanding to the prediction of potential new sites of gold mineralisation. The project follows a series of stages from identifying the key parameters required to construct and test simulations through to reverse engineering of known deposits and ultimately applying the conditions identified in the preliminary stages to predictive simulations. Results of the modelling demonstrate strong geometric controls of the localisation of fluids during mineralisation. An&nbsp;EXTENDED ABSTRACT&nbsp;is available for download. A full-length paper was not&nbsp;prepared for this presentation.

Jan 1, 2008

By Wilson A. F

The use of stable isotopic measurements as a technique for elucidating the origin and history of the water in hydrothermal fluids is relatively new. Recent studies have emphasized the importance of meteoric water in the formation of many hydrothermal ore deposits including many epithermal gold-base metal deposits which occur in faulted volcanic terrane. Other vein-type gold ores are be- lieved to have formed from fluids of magmatic or metamorphic origin and exhibit characteri stic 6180 values. These values also give information regarding temperatures and the degree of equilibrium. Preliminary oxygen data for some important gold deposits of eastern Australia are evaluated in the con- text of styles of mineralization.

Jan 1, 1980

By J S. Kuszmaul, T O. Aspinall

The applicability of environmental geotechnics for erosion management is increasing in importance worldwide. The environmental impact of mining and evolving environmental legislation has been receiving increased attention worldwide in the last two decades (Bradfield, Shultz and Stone, 1996). The potential impacts associated with unstable spoil dumps from mine operations is the focus of concern both by the mining industry, environmental legislative agencies and members of the public. This is because of the need to increase the reliability of erosion prediction and in the minimisation of costs for spoil dump design. Engineered slopes of mine spoils may be stable at the end of construction, but they can deteriorate over time. Engineering design of mine spoil dumps seeks to reduce the potential for such erosion damage through correct selection of an initial stable landform scheme (Goh, 1997). The design of mine spoil dumps must also conform to the specifications of evolving legislation. The Queensland Environmental Management Overview Strategy (EMOS) states that, for minimised degradation of the surface area due to erosion during the development of a project, the erosion rates should be between 12 - 40 tonnes/hectare/year and that the depths of rills and gullies be limited to less than 30 cm (QDPI, 1988). The aim of engineering design is to ensure the long-term stability of the spoil dumps. The implementation of effective planning and operating procedures through recontouring and grading assists in the reshaping of spoil dumps to a safe, stable and non-erodible environment.

Jan 1, 1998

By C D. Strickland

Western Australia (WA) has been a significant world producer of titanium minerals (rutile, ilmenite and leucoxene) and zircon for over 55 years. In 2010, despite global difficulties, WA accounted for&nbsp;12 per cent of world production for zircon, ten per cent for ilmenite, and eight per cent for rutile. With downstream processing, titanium minerals (ilmenite, rutile, leucoxene) and zircon exports for 2010 were valued at $511 M (Department of Mines and Petroleum, 2010).Production is dominated by two areas of the Perth Basin, namely the Eneabba and the Bunbury-Capel regions, which are located 240 km north and 200 km south of Perth respectively. Mineralisation is within Cenozoic beach or near shore dune deposits at three broad altitudes related to the present coastline, and two older higher sea-level still-stands. The titanium-zircon minerals presumably were derived from the underlying Mesozoic sediments of the Perth Basin. Contrary to expectations, age dating suggests that the ultimate source of most of this mineralisation was not the adjacent Yilgarn Craton. With the cooperation of industry, the Geological Survey of Western Australia has mapped all known significant titanium-zircon mineralisation within the Perth Basin. This mapping has identified ‘strategic mineral resource protection areas’ that should be set aside for future mining, ‘sterilised’ and ‘mined’ areas that generally do not restrict land use options, and ‘possible strategic resource areas’ which have exploration potential for hosting titanium-zircon mineral deposits.The Perth Basin is currently undergoing rapid residential and industrial development. By informing all stakeholders of the locations of potential mining areas, the titanium-zircon mapping has the ability to reduce future land use conflicts, and facilitate sequential land use planning. Appropriate planning measures are being implemented to ensure that the Western Australia’s titanium-zircon minerals industry remains strong and viable in the future.

Oct 5, 2011

By N Burgio

Block cave mines are often thought of as rock factories where high volumes of production are mined from a fixed area suggesting little requirement for geological input and control. Yet caving operations have peculiar and specific technical requirements from prefeasibility through to post-mining reconciliation. Whilst essential elements such as resource definition, geological interpretation and sampling strategies are common to all mining methods, planning for a block cave requires a different emphasis and philosophical approach in how we deal with these issues. We will examine why a geoscientist’s input is critical towards the successful planning, design and monitoring of a caving operation.

Aug 22, 2011

Techno-Economic Evaluation of a New Early Removal Process to Treat High-Arsenic Copper Ores

Sep 13, 2010

By A Geldenhuis, M Hagger, J Maree

Disposal of mine water is a worldwide problem occurring in the coal and gold as well in the metal ore mining areas. Since southern Africa is a (semi) arid region, mining effluents should be treated to qualities such that they can be used for agricultural purposes or that they can be discharged in river system. Studies have shown that partly treated acid mine water can be used for irrigation. A copper mine in Botswana plans to use 5 M/d of treated mine effluent for the irrigation of agricultural product. The results of this study showed that when applying the biological sulfate removal technology the produced sulfide precipitated the metals in the mine effluent, such as nickel, Zn and Mn, to metal sulfide (MeS).

Jan 1, 2003

By Adranyl W. W

Sub-level caving with bottom ore drawing has gained wide acceptance in rich, soft, low magnetic iron ores because it provides moderate ore dilution and ore losses. The main problem here is the high rock pressure exerted on sub-level drives situated in the sub-level sill pillars. To reduce this effect, the ore block is divided into panels. This paper illustraes the method of determining the maximum panel width providing low maintenance cost of sub-level drives.

Jan 1, 1995

By Brechtel C. E

Providing adequate airflow to effectively dilute and remove diesel pollutants in large mine working headings is a little researched area. A simulated diesel mucking operation was carried out in the Exxon Colony Pilot Mine in Colorado to establish expected levels of diesel pollutants in dead-ended working headings. This heading was nominally 15.3 m (50-ft) wide by 9.2 m (30-ft) high. Two face ventilation systems were tested using sulfur hexafluoride tracer gas to represent the diesel pollutants. The results of these tests showed that conventional face ventilation systems operating at high flow rates could adequately ventilate diesel equipment in the 447-522 kW (600-700 hp) range, even in a dead heading 91.4 m (300 ft) in length.

Jan 1, 1988