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ABSTRACTOperations Research and associated techniques have wide application in the Mining Industry and have been used in Mount Isa since 1961.Typical of the projects undertaken by the OperatIons Research staff are1. the development of a complex computer programme for use in economic evaluation of mineral deposits,2. development of a production scheduling and control system for a complex mining operation,3. SImulatIon of a metallurgical plant operation to test the adequacy of design specifications and4. analysis of vehicular accident data to valuate alternative courses of insurance action.

Jan 1, 1968

The Estonia Mine, operated by Eesti Energia Kaevandused AS (EEK), the mining division of the Estonian Government's energy company, Eesti Energia AS, is a large room and pillar mine located in Eastern Estonia. It supplied approximately 4.9 Mt/a of oil shale in financial year ending 2010, which is used for electricity and shale oil generation. Due to the Estonian climate and the power station's need for a dry product, Estonia Mine has developed a planning system where short-term demands of the power stations dictate the schedule. Such an arrangement requires maximising flexibility and consequently the mine only operated for 199 days in 2010.The footprint plays a key role in achieving mass mining rates as the 12 km + 12 km lease area allows the mine to split into mining districts that act independently of each other and maximise the number of work areas available. Coupled with this, the geology of the mine is relatively homogenous over the mining lease, simplifying the mine design and production methods.During the last five years, EEK has commissioned a comprehensive conveyor network. Consequently, material handling only requires loaders to dump oil shale direct from the production face onto a chain conveyor that feeds the conveyor network that ultimately supplies the enrichment plant. Dewatering is also of critical importance, with 90 Mm3 of water discharged annually. EEK uses large trenches up to 3.5 m deep and 1.2 m wide to channel groundwater. Track mounted mechanical saws are used to cut slots in the floor, to control overbreak in blasting these trenches.EEK has introduced Salzgitter Machinenbau GB 280S auger drills that drill three 280 mm diameter holes simultaneously. This has improved void hole drilling times and reduced the drilling required for each face, reducing the overall production cycle time. Blasting activities have also been decoupled from other mining activities negating the need for firing times through the use of small independent firings, required to control vibrations.

Dec 6, 2010

By S F. Simmons

The Ohaaki Rhyolite and the Rautiwiri Breccia are two volcanic units occurring in the shallow and deep parts of the Broadlands-Ohaaki geothermal system. Alteration of these units by chloride waters results in distinct mineral assemblages that also have distinct whole rock compositions. The Ohaaki rhyolite is altered to an assemblage dominated by quartz, adularia, illite and pyrite as a consequence of silica, potassium and sulfur metasomatism. Locally, these rocks contain up to 0.5 ppm Au. The Rautiwiri Breccia by contrast is altered to an assemblage dominated by albite, adularia, quartz, illite, chlorite and pyrite in association with modest sodium metasomatism. Whole rock oxygen isotope compositions of altered rocks range between 3.3 and 7.5 ë, and are generally lower compared to their fresh rock equivalents having values of 9.5 to 10.6 ë; the result is broad pattern of lower values with increasing alteration intensity.

Jan 1, 2002

Martha Mine is an open pit gold-silver mine, located within the township of Waihi, 150km southeast of Auckland and is operated as a joint venture between Normandy Mining Ltd. 67 %) as Manager and Otter Gold Mines Ltd. (33%). The deposit was historically mined, by underground methods from 1888 to 1952, producing 5.5 moz of gold and 30 moz of silver, from 11 mt of ore. The current operation began in 1988, producing, to June 1999 - 867,245 oz of gold and 5.5 moz of silver from 9.5 mt of ore. The licensed reserves were due to be mined out by late 2000. Consents were granted in December 1998 to allow the expansion of the operation through to 2007 accessing an additional 7.5 mt of ore at 3.4 gpt Au and 26.0 gpt Ag for 800,000 oz of gold and 6.4 moz of silver. The key elements of the expansion are: 1. Pit enlargement 2. Upgraded crushing and material handling facilities 3. Construction of a second tailings storage facility 4. Upgraded water treatment capacity 5. Increased operating capacity This paper presents an update of expansion activities to date.

Jan 1, 1999

By using knowledge-based technology to create a Virtual Mining Enterprise and integrating it with existing technical and financial computer systems, a gold mining company has been able to reduce the time taken to produce a mine plan from 14 weeks to less than one week. Typically, the mine planning process requires circulating and managing large amounts of information. Even with the use of computers in todayÆs business, this is often still a manual process involving file transfers and individualised spreadsheets. Mine planning also involves understanding and managing large quantities of complex and interrelated variables. Added to this is the ever changing dynamics and constraints associated with the business of mining. These issues not only hamper the planning process but also question the validity and usefulness of the mine plans being generated. By integrating the information and knowledge of the numerous departments involved in mine planning into one core Knowledge Base - so called æone version of the truthÆ, - mining companies are able to overcome these pitfalls experienced in traditional planning methods. Once set up, the Knowledge Base creates and runs a virtual mining enterprise with which to visualise and test various scenarios of mining, business and logistical activities. The final output is an optimised enterprise-wide plan with clear and detailed instructions for each of the divisions of the company.

Jan 1, 2000

By Johnson T, Huynh D

The State Electricity Commission of Victoria is conducting a program of research and development into alternatives to the use of conventional boilers for the generation of electricity from brown coal. The objectives of the program are to reduce the cost of electricity generation and also to improve the thermal efficiency so as to reduce the emission of greenhouse gases and other pollutants. The program presently includes the following four technologies: Hydro-thermal Drying, Direct Coal Fired Gas Turbine, Integrated Gasification Combined Cycle, and Steam Fluidised Bed Drying. The Hydro-thermal Drying process produces a combustible coal-water-slurry fuel which is suitable for use in a coal fired gas turbine. The coal fired gas turbine has the potential to produce electricity at a lower cost than conventional power stations and when combined with a steam cycle, it will also use significantly less coal. The Integrated Gasification Combined Cycle process gasifies the coal, cleans the gas, and then bums it in a gas turbine/combined cycle. This process is being developed in Europe and the USA in order to meet their stringent emission regulations. It offers Victoria cleaner more efficient and cheaper electricity.

Jan 1, 1992

The objective of a mine planning exercise is to plan a safe mine that maximises net present value (NPV) for the project. Two primary elements are key to design of a mine plan optimised to maximise profit: selection of an optimised production rate and selection of an optimised equipment fleet. Both depend upon accurate estimations of capital and operating costs for the equipment and for the life cycle of the mining operation. Once a trial production rate is determined, a primary equipment fleet, ie excavators, haulers, and blasthole drills, can be determined based on material characteristics and haulage distances and gradients. An auxiliary fleet, dozers, road maintainers, service trucks, etc can be determined using less rigid productivity criteria. With an equipment fleet determined, operating and support personnel can be assigned based on shift requirements and equipment operating needs; and material and supply requirements can be estimated. Knowing the areal dimensions of the major equipment items, road widths and repair shop dimensions can be determined. Personnel numbers and supply requirements determine the square metre sizes of offices, change rooms, and storage facilities. Reliable sources of capital and operating unit prices and costs for all these items are referenced in the paper. Once preliminary capital and operating cost estimates are calculated by applying unit costs to equipment, personnel, material and supply needs, potential profit can be tested using DCF techniques. An optimised mine plan can then be determined by testing the potential profitability of multiple mine production rates. Because of the economies of scale, full capital and operating cost estimates must be completed for each production rate in order to produce meaningful comparisons.

Dec 6, 2010

By D Kotzen

Online cyanide analysers have been successfully used to control free cyanide in the gold/silver leach process for over 15 years. Use of such analysers leads to cyanide savings and improvement in recoveries. Plants with leach cyanide analysers show both lower and more consistent cyanide levels in tailings. Cyanide code compliance requires meeting residual cyanide targets in tailings. Monitoring and logging of the residual cyanide in plant tailings and effluent is required. Meeting targets may require cyanide recovery/destruction processes to be implemented. The operating cost of destroying cyanide is often the same order of magnitude as the cyanidation cost. Various cyanide destruction and/or recovery processes are reviewed. Choice of a process consistent with the environmental and operational requirements is illustrated. Online weak acid dissociable cyanide (CNWAD) analysers have recently been developed and introduced on gold plants. The application of a WAD 1000 online CNWAD analyser at a large gold plant is presented. The analyser ensures code compliance, reduces cyanide destruction process operating costs and forms a historical record of CNWAD values in tailings.

Jan 1, 2007

The mineralogy, textures, and genetic significance of a silver-rich siderite vein and an apparently co-genetic galena vein from the South mine, Broken Hill are discussed.Both veins cut sharply across the Main Lode Horizon and appear to be coeval with thc A.B.H. Consols lode.The minerals of thc siderite vein apparently result from the preferential leaching of silver from Main Lode Horizon ore with a demonstrable "breakdown series" commencing with tetrahedrite, passing through silver sulpho-salts, and ending with simple binary compounds or with elemental silver.The siderite vein has been deposited by metahydrothermal fluids along the lines of Schneiderhohn's "secondary hydrothermal" mineralization.

Jan 1, 1968

By D Craw, K A. Hunter

Deposits of the metalloids arsenic and antimony occur in quartz veins of mesothermal hydrothermalsystems in the South Island as arsenopyrite (AsFeS) and stibnite (Sb2S3). Arsenopyrite and stibnite occur in natural exposures in gold-mining areas, and additional arsenopyrite and stibnite have been exposed to the atmosphere by mining activity. At present the drinking water limits for dissolved As and Sb are 10 ppb and 3 ppb respectively. Sampling and analysis techniques are critical to determination of metalloid concentrations at these low levels. Endeavour Inlet in the Marlborough Sounds is an historic mining area (late 19th Century) with elevated As and Sb in waters emanating from mineralised rocks. Waters running out of abandoned adits have concentrations of As and/or Sb up to ppm levels. Natural waters have high Sb and low As, and the As levels increase markedly where anthropogenic activity has exposed rock. Changes in Sb/As ratio could potentially be used to quantify the anthropogenic component of metalloid mobility on mine sites on the 100-year time scale.

Jan 1, 2002

This paper forms the second of a series, in which it is proposed to communicate the results of an extensive research into the influence of alloying elements on the physical properties of lead, now being carried out in the Metallurgy School of the University of Melbourne.Some general comments on this research were made by the present writer as an introduction to the first contribution by R. S. Russell*: It was there pointed out that it was the intention to prepare lead as pure as possible, to determine its properties and then to make alloys with the various elements added singly, and in various combinations, in order to determine the effect of each. This line of action is still being pursued.It occurred to the writer, however, that this fundamental attack might, with advantage, be accompanied by a parallel investigation in which lead of commercial purity would form the basis material. In this way, using a standard *Professor of Metallurgy, University of Melbourne.

Jan 1, 1934

Study on the Reasonable Mineral Processing Technology of a Cu-Mo Ore

Sep 13, 2010

A new test coke oven of 7 cu. ft. capacity is described. The oven was designed to simulate conditions in a central section of a battery oven and a special feature is the achievement of unidirectional heating from theflues on either side of the charge.The method of charging permits close control of charge conditions such as bulk density and moisture content.These conditions, as well as coking conditions (e.g. flue temperatures and coking time) must be varied to simulate conditions in different batteries. The effects of several variables on coke quality are discussed.Using test oven conditions corresponding to those of Newcastle steelworks batteries, good agreement was obtained between strength indices of test oven and battery cokes. For 17 tests, the average ASTM stability and hardness indices for the test oven coke were 38· 5 per cent and 69·7 per cent, while those for the battery coke were 37· 4 per cent and 67·6 per cent.Observed relationships between coke yield and productivity, and volatile matter and charge moisture are given.The use of a test oven to classify test coals into prime-, medium-, poor-, and non-coking coals is discussed.This may be achieved by observing the effects of the test coal in blends with other coals. The results of a series of blending tests are presented.The dangers of attempting to predict coke quality from a single coal property are pointed out, since this can be done only for very restricted ranges of coals.A diagram is given showing the established trends in the effects of blending various types of Australian coals on coke strength.

Jan 1, 1970

The leaching characteristics of a number of Australian uranium ores were determined under acid and alkaline conditions. Ores from the Ranger, Nabarlek and Koongarra deposits in the Northern Territory were readily leached in dilute sulphuric acid. Suitable processing conditions were: leaching at 35-40°C, pH 1·52·0 and redox potential -475 mV for periods of 16-24h with ore ground to 50 per cent -200 mesh CB.S.S.). Ore from the Roxby Downs deposit in South Australia required leaching at 55°C and a redox potential of -650 mV to achieve a satisfactory recovery. All ores contained refractory minerals which were not leached under conventional conditions, limiting uranium extraction to 86-96 per cent.Carbonate leaching of carnotite in calcrete ores from Yeelirrie and Lake Way in Western Australia yielded uranium extractions of at least 98 per cent. Leaching rates were considerably faster than those reported for other applications of alkaline leaching as the slow oxidation step was not required.

Jan 1, 1979

By Kelsall D. F, Trahar W. J

The size by size batch flotation behaviour of copper activated sphalerite from synthetic mixtures with quartz was determined. In terms of recovery of sphalerite, the size fractions could be grouped into coarse, intermediate, and fine ranges. The behaviour of the coarse and fine ranges was significantly poorer than that of the intermediate range in both the extent and rate of flotation.Each size fraction had a fast and a slow floating component.The main effect of changing the copper sulphate addition was to alter the proportion of any size fraction which was fast floating. No correlation could be found, between the amount of copper on the spha:lerite andeither the flotation rate of the mineral or the amount of copper added to the system. It was found that fine particles did not appear to consume greatly disproportionate amounts of copper sulphate during conditioning. A modified conditioning procedure was found to lead to a higher rate of flotation and recovery of coarse sphalerite and to make poss1ble substantial savings of copper sulphate.

Jan 1, 1975

By S Jephcott

The McArthur lead-zinc-silver deposit is of the stratiform type. It consists of a mineralised bituminous shale sequence containing some tuffites, numerous graded beds and isolated slump breccia horizons. The principal sulfides; pyrite, sphalerite and galena, are essentially restricted to the shales and the genetically unrelated turbidites contain only minor mineralisation. The geochemistry of the deposit has been investigated with respect to the stratigraphic column and mineralogy of the sediments. A sedimentary origin is advocated for the deposit. Volcanism, thermal spring activity and high salinities, perhaps related to the Emu Fault, are considered as contributing factors to ore genesis. The metallurgy of this deposit is discussed in relation to its geologic history.

Jan 1, 1971

By G B. Smith, G M. Marshall, A Querzoli

The South Australian mining regulatory framework has adopted a performance based approach to the management of risk. This approach has been in place in South Australia for more than 10 years and is increasingly being implemented in mining jurisdictions in Australia and around the world. Performance based regulation focuses on setting appropriate environmental outcomes to be achieved based on an assessment of the potential impacts associated with the development, operation and closure of mining projects. Measurable compliance criteria, including completion criteria, are set to demonstrate achievement of the outcomes. It is the responsibility of the proponent to propose designs and strategies that will achieve the regulated environmental outcomes and to demonstrate the implementation of their designs and strategies will achieve the outcomes into the future. Tailings Storage Facilities (TSFs) are significant elements of many major mines and each is unique with site specific factors such a materials to be stored, design, size, location, climate, sensitive receptors, operating history of the facility (i.e. changes to design), site culture and company capability amongst a range of other factors. Consequently a fit-for purpose approach is a key principle of best practice regulation of tailings management as it takes the site specific factors into account in setting appropriate outcomes for mitigating the identified impacts associated with a proposed development. Achievement of those outcomes through fit-for purpose, well designed management strategies would ensure safe, stable and economic storage of tailings in a manner that complies with all legislative requirements and presents negligible public health and safety risks. Tailings storage must also have acceptably low social and environmental impacts, both on and off site, during operation and indefinitely post closure. Achievement of environmental outcomes during operations and at mine completion can then be demonstrated to the regulator and community through public reporting of compliance with measurement criteria which establish the appropriate level of impact for each individual operation. A number of new mining proposals including tailings storage facilities (TSF) have recently been assessed and approved in South Australia. The location, size, design, sensitive receptors, public interest and therefore risk profiles of these TSF’s have varied substantially between these new mining proposals. These considerations were reflected in the assessment of the TSFs and the resulting mining lease conditions of approval including the environmental outcomes to be achieved over the life of the facilities. This paper and the accompanying presentation will provide case studies of recently approved TSFs within South Australia and the regulatory framework for each case.CITATION:Smith, G B, Querzoli, A and Marshall, G M, 2018. Tailings regulation – a South Australian perspective, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 166–177 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

Rutile Beach Sand from Hard Rock

Sep 13, 2010

By J Dwyer, M Hill

Downer’s mining division has made an operational and financial commitment to developing engineered solutions that mitigate the risks associated with operator proximity to uncontrolled development drill boom movements, and unguarded rotating drill steels.With the potential for serious injury or fatality, these identified risks are categorised as critical. Previous attempts by the industry to engineer them out have produced limited success, with numerous incidents still occurring year on year. Ultimately, the industry (as a whole) remains reliant on procedural prevention for operator safety.Downer understood the success of such an initiative would largely depend on the effective collaboration between operational experience, technology experts and automation. With so many variables requiring consideration; such as physical operator movement, machine boom movements, variable machine positions, and underground environmental impacts – challenging traditional technologies was necessary to deliver an optimal solution.For that reason, discrete detection (similar to laser curtains or beams) was considered not fit for purpose. The use of situational mapping, using rotating lasers, however, provided the optimal solution. The lasers collect data that is then processed using a custom software application.The software application is specifically programmed for tracking and classifying objects within detection zones, using advanced algorithms and filtering. Recognition and removal of non-positive disturbances are possible without losing personnel detection capability. The detection of relevant classified objects (humans) is determined by analysis of object size, age, movement, and speed etc. When the relevant object is detected, an alarm and inhibit function is applied preventing drilling functions.Any breach of the safety zone (forward of the front jacks) will automatically disable the hydraulic boom function. This can only be reset in the cabin once the person or persons have returned past the front jacks of the development drill into the safety zone.Downer, in collaboration with partner YUMARR Automation, has successfully developed this reliable boom isolation system, and is called JumboGuard. The system has now been commissioned and installed across all Downer Mining development drill fleets, operating in Australia.CITATION:Hill, M and Dwyer, J, 2017. JumboGuard – automatic boom isolation system, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 287–294 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By Lonie W. M

The rapid development of the Australian steel industry over the past twenty years has greatly increased the demand for coking coal from the collieries owned by the Broken Hill Proprietary Co. Ltd. and Australian Iron & Steel Ltd. This in turn has called for an intensive and continuous programme of colliery expansion and new colliery development, along with the reorganization and modernization of existing collieries.This paper presents a general description of the factors involved and the techniques used in planning modern colliery development for the steel industry.PRELIMINARY GEOLOGICAL INVESTIGATIONSIn any colliery development, preliminary geological investigations require a detailed and practical knowledge of the geology and characteristics of the coal-field as a whole. In the early stages of the investigations, probably the most valuable information is obtained from outside the particular area under review, rather than within it, and unless the geology of the coal-field is understood, the projection of the known information into the unknown area cannot be carried out with certainty.Because development of the coal seams from the outcrops has been an apparently simple matter and not subject to the risks involved in deep mine development, the geology of the New South Wales. coal-fields has not received the attention that major mineral resources warrant.Only the most accessible regions of the coal measures have been generally prospected, while the potential areas remain...

Jan 1, 1957