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By R Gilbertson, N Freeman

Metallurgical accounting is key to the control and production planning process of any mining operation. This is even more crucial for complex operations involving mining, concentration, smelting, refining and marketing. The tracking of multiple metal product and contaminant components through the operation can improve process predictability and inventory management. Appropriate use can be made of æhigh quality dataÆ for strategic reserve utilisation, mining operations, milling operations, etc. This information enables the optimisation of all aspects of the mining and processing operations. This case study discusses a metal balance implementation for WMCÆs Olympic Dam operations; a large integrated mining, concentration and refining operation, which used an existing off the shelf statistical data reconciliation package developed for the oil industry. It was extended to track and balance the metal co-products across the entire integrated mining, mineral processing and refining plant. The key benefits discussed are tight integration with existing data collection systems, formalisation of previously informal processes, and leveraging the development and support available for a widely used package. The project provided a solution for the site metallurgical balance spanning the mine and processing plant. The solution facilitates a bridge between the planning and production worlds, using a common data model across the site.

Jan 1, 2002

By Falconer A. J

Two magnetic parameters are proposed as a basis for the assessment of ironsands beneficiation. The parameters are deter- mined for raw sand prior to dredging and for magnetic separator head feed over a production period of five months. The relationships between these parameters and the performance of the magnetic separators are examined to establish the value of magnetic assessment compared with the traditional soluble iron assay method. The results illustrate that the first parameter, true magnetic fraction (TMF), has a value superior to that of soluble iron when relating raw sand grade calculated by tri- angulation to magnet performance. In terms of the relationship between magnet head feed grade and magnet performance, TMF and soluble iron perform equally as assessment parameters. For the ironsands mined during the five month period, the second magnetic assessment parameter, composite fraction (CR), is shown to merely reflect TMF and offers no additional information for assess- Ment. Conclusions are that true magnetic fraction has many advantages over soluble iron in terms of time and cost of determination and that it is a meaningful and reliable parameter upon which to base all calculations relating to the mining and beneficiation of ironsands.

Jan 1, 1980

The Gympie Province is a unique tectono-stratigraphic unit which does not fit into the overall palaeogeographic pattern of the New England Fold Belt (NEFB), and part of it has been proposed as an exotic terrane more closely linked to New Zealand. From E to W the Gympie Province comprises 6 distinct units which can be evaluated as suspect or exotic terranes.

Jan 1, 1990

By Membrey W. B, Partridge A. C

Lower transportation costs, improved handling and better utilization efficiency are some of the reasons that make low moisture coal product desirable. There has been considerable interest in the development of effective coal dewatering techniques to achieve this result. One avenue of considerable merit for enhancing dewatering processes is by modification of the surface chemistry of the coalwater slurry system by chemical means, resulting in better performance of existing equipment. This paper reports the results of an investigation of the utility of surface active agents in the enhancement of fine coal dewatering. A large variety of proprietary dewatering agents have been studied in relation to their efficiency in enhancing the dewatering of a number of Australian coals. Properties of particular coals that make them amenable to improved dewatering by particular chemical agents have been identified. Surface studies, including surface tension and zeta potential measurements as a function of surfactant concentration, as well as dewatering assessments, were used. Particular attention was paid to filtration, but the results could be applied to other dewatering systems.

Jan 1, 1989

By Finlayson E, Hilyard D

1:100 000 geological mapping of Bougainville Island has resulted in refinement of stratigraphic subdivisions and relationships. We subdivide the sequence into basement Atamo Volcanics (Late Eocene-Early Oligocene), consisting of spilitised pillow basalts, which are overlain unconformably by Late Oligocene-Early Miocene Keriaka Limestone. The latter is unconformably overlain by fine-medium grained volcaniclastics and minor lavas of the Middle-Late Miocene Toniva Formation which coarsens upward and passes gradationally and conformably into the coarsely volcanolithic latest Miocene-Pliocene Arawa Conglomerate. The Kupei Complex, host to the Panguna.porphyry Cu-Au deposit, consists of medium - K20 microdiorites, granodiorites, and andesites intruding Arawa Conglomerate and Toniva Formation. K/Ar isotopic dates on the Kupei Complex range from 4.8-1.3 Ma, and hence overlap the age of the Arawa Conglomerate. We believe that the Arawa Conglomerate consists of mass flow deposits on a volcani- clastic apron surrounding a volcanic edifice above the intruding Kupei Complex.

Jan 1, 1990

Computer-based block modelling of orebodies is now used at Renison Tin mine for the estimation of ore reserves. It is considered that this has resulted in improved reserve estimation for complex 'stratafault' orebodies. The results for all orebody types are more easily understood by the mine planning section and provide greater scheduling capability than those from the previous manual isoline reserve estimation method. A structural overview of the deposit can be gained by combining geological block models for the various orebodies. It is anticipated that upon completion of block modelling for all the orebodies the time spent on the annual ore reserve estimate will be significantly reduced.

Jan 1, 1990

Proposals for engineering works in the River Dement in recent years have been made in the context of very little geological informat- ion. Breakage of the Tasman Bridge, forced a complete re-appraisal and collection of inform- ation in order to select a new site and predict problems. Seismic, magnetic and gravity methods foll- owed by drilling have allowed an assessment of the nature, thickness and distribution of mater- ials underlying the river bed. Key discoveries included recognition of low seismic velocity silts (1100 m/s) and a separate channel for the river since the Late Tertiary.

Jan 1, 1977

By Singh DP, Singh TN

The present study attempts to critically review the pillar-design as required by Coal Mines Regulations of India vis-a-vis latest rockmechanics formulae. Equivalent material modelling was the approach adopted for testing the safety and stability of the pillar sizes predicted by various formulae. Two parameters, considered here for calculating pillar sizes was the stresses acting over the pillars and the strength of the pillars. Stresses acting on the pillars were calculated by the tributary area method. Based on the studies of Coates and Hustrulid, the stress obtained was reduced by 40 percent. For calculating the strength of the pillars, three formulae, namely Holland and Gaddy, Salamon and Munro and Central Mining Research Station, India, were used. The pillar widths were then determined by equating the product of recommended factor of safety and pillar stress with the pillar Strength.

Jan 1, 1992

FOR some time past keen interest has been shown in both America and South Africa in the mining drill-steel problem. This interest has extended to Australian mining fields, and Australian drill users, ever desirous of increasing efficiency, are vigorously attacking the problem. The writer has recently been engaged in the investigation of the problem on two of ,the biggest mining fields in Australia, and has formed very definite conclusions concerning the causes of many drill-steel casualties. He puts these views forward in the hope that they may be of interest to, both drill manufacturers and drill users. The subject is here dealt with mainly from the aspect of the properties of the steel and the modifications of these properties whensubjected to various manipulations. It is generally admitted that the drilling machine has greatly increased in power and efficiency during recent years, and the consequence is that the machine is demanding better service from the steel. This is being impressed on the drill users by an increase in steel casualties. This fact has led many mining people to the view that the machine has developed so rapidly that the steel maker has not been able to keep pace, and that consequently the steel isfailing by fatigue 0:1; so-called crystallization. This view is rather depressing. The writer, on the other hand, is inclined to discountenance fatigue as a serious factor under good normal working conditions where the steel is carefully manufactured and supplied to the user under suitable structural and sound conditions, and has subsequently received kind treatment at the hands of the drill sharpener and the drill user.It is not reasonable to attribute failures to fatigue until it has definitely been proved that the steel is fundamentally sound and is in the best structural condition to resist the stresses it is called upon to withstand, and, this being so, that all fundamental principles of...

Jan 1, 1923

By Szymanski J

Although efforts towards producing a `total quality rockfill product' have allowed cemented rockfill costs to be reduced considerably, there is still tremendous potential for further cost reductions. Cemented rockfill costs range from approximately $7 to $12 (US) per tonne of fill placed. Approximately 50 per cent of the rockfill costs are associated with cement costs. A large portion of the remaining 50 per cent is associated with labour and materials handling costs. Several Canadian underground mines utilise haulage trucks and/or conventional belt conveyors to distribute the rockfill. However, due to the restrictive nature of the underground environment, these current materials handling systems have limitations (ie spillage from trucks, dust from conveyors). The Sicon conveyor system (developed in Sweden) has considerable potential for replacing these current methods. The Sicon conveyor utilises a revolutionary approach - the conveyor belt is folded over upon itself (forming a tear drop shape) so that the transported material is completely encased within the belt. The Sicon conveyor's ability to negotiate very tight comers (without transfer points) makes the conveyor very appealing for underground mining applications. An analysis comparing the pros and cons associated with the Sicon conveyor system versus conventional materials handling systems will be presented in this paper.

Jan 1, 1995

INCREASE OF CATASTROPHE FREQUENCY AND SEVERITYIn the last couple of decades the frequency of natural catastrophes has increased dramatically. This realization results from the statistical analysis of the comprehensive loss data that we have been collecting constantly over the last 30 years and have evaluated in connec-tion with the preparation of our "World Map of Natural Hazards", which is now in its second edition (Munich Re, 1988). Each month brings data on between 30 and 50 new loss events. Fortunately, however, only a few of these have to be added to the list of major natural catastrophes, that is only those involv-ing damage that considerably exceeds what the country or region concerned can handle itself so that substantial na-tional or international aid is required. That is generally the case if the number of dead runs into the hundreds or thousands, if tens or hundreds of thousands of people are rendered home-less and if the total economic loss is in the region of US$ 100 million. These major catastrophes, about which we have fairly comprehensive data even in the case of those that occurred farther back in the past, numbered only 14 in the 1960s but 70 in the 1980s; they there-fore increased over a period of 30 years by a factor of 5. The trend is also very clear when we consider the total economic loss, which - adjusted for in-flation - increased during the same period from an average of US$ 3.7 bil-lion per year to US$ 11.4 billion, i.e. by a factor of 3.1. The insured losses, finally, increased by as much as a fac-tor of 4.8.

Jan 1, 1990

By D Mukendi-Ngalula, G Hearn

Beach sand minerals from the volcanic rock structures of the Drakensberg, Kwazulu-Natal, (South Africa) have been processed. Screening, flotation, spiral concentration and magnetic separation methods were used either separately or successively in an attempt to concentrate monazite minerals. Products thereof and those from a long time (up to 72 hours) microwaves treatment of the finally produced ilmenite-bearing minerals have been studied using the M÷ssbauer effect spectroscopy. The 57Fe M÷ssbauer effect spectroscopy has demonstrated its versatility and power in monitoring the ilmenite internal reduction mechanism and products and, in characterising the iron-bearing phases contained in different products from the beach sand minerals processing. Microwaves heating of ilmenite for up to 38 hours reduced internally the Fe3+ from the ilmeniteÆs structure. A more prolonged microwaves heating (up to 72 hours) re-oxidised the mineral. 61 per cent natural ilmenite recovery was obtained in the floating products of a spiral concentrated -212+106 ¦m screened and beach sand minerals fraction. A preferential concentration of hematite with a 62 per cent recovery was found in the sinking products while the combination of screening-spiral separation-magnetic separation and flotation yielded a floating product with the highest ilmenite and the highest hematite abundanceÆs (71 per cent, 19 per cent respectively). A natural ilmenite containing 87 per cent ilmenite and 13 per cent hematite could be produced and extracted from the sinking products of the flotation process collected subsequently to the spiral concentration and the initial screening.

Jan 1, 2000

By Motyka J, Adamczyk AF, Witczak S

A case study of migration of a paper factory fluid wastes, on the distance of 5 km from an underground disposal site to an ore mine is presented. The ore mine in question, situated in SW Poland is pumping 3.5 m3/s (ca 300 000 m3/day) of groundwater, producing a cone of depression about 150 m deep and several kilometers wide. The migration of wastes (pollutant) occurs within the carbonate karstic aquifer of Triassic age. The aquifer is about 100m thick and is characterized by the coefficient of hydraulic conductivity equal to 8 m/day on the average. The results of systematic measurements carried out for 13 years enabled to estimate the mean breakthrough curve of the pollutant. On this basis and taking into account the coefficient of hydraulic conductivity as well as the mean hydraulic gradient between the disposal site and the ore mine, the migration parameters of the polluting material, i.e. the real flow velocity, the effective porosity and the longitudinal disper- sivity have been calculated. As the measurements considered a long migration distance of the pollutant, the obtained hydrodynamic dispersion constant (dispersivity), in the authors opinion, is reliable enough to be applied for regional groundwater calculations, regardless of the "scale effect".

Jan 1, 1988

By Jensen B

The investigation of the explosion characteristics of nine Bowen Basin (Central Queensland) dust samples in a suitable coal dust explosion chamber using a new dust concentration probe provides several advances in the area of coal dust explosibility testing. The 20 litre explosion chamber, of novel design, uses rotation of the main body of the chamber together with air jets for dust dispersion, and allows testing of different types of explosion initiators and analysis of the explosion characteristics of coal dust/methane mixtures of varying concentrations.A new development was a dielectric dust probe for the measurement of coal dust concentration. A capacitive micrometry technique was successfully adapted to measure dust concentration. The system uses a ratio-transformer bridge for measurement of small changes in a capacitive probe designed to sample a representative volume. The device is accurate, and is capable of operating in the hostile environment within the explosion chamber.The explosion chamber and dust probe characterise the explosive potential of coal dust samples by determination of the dust lean limit concentration in varying mixture with methane. Plots of lean limit points obtained in this way present an explosion curve for each sample which indicates the potential of the coal dust/methane to explode under the conditions of initiation in the chamber. The explosion curve obtained for each sample presents a unique signature that appears to reflect the physical and chemical characteristics of the dust.The results from this series of laboratory experiments appear to provide a useful index and indicate potential areas of interest for future research.

Jan 1, 1991

By Kay JR

In 1984 a new Regional Geological Mapping Program (RGMP) was commenced by the Geological Survey of Queensland (GSQ); the new program was in response to the withdrawal of the Bureau of Mineral Resources from regional mapping. Areas for mapping were selected in northern and south-eastern Queensland on the basis of potential for mineral discoveries, level of company interest, inaccuracies in the first edition mapping and interests of other organisations (government and universities) in joint projects.Geological provinces of particular interest in northern Queensland are the Hodgkinson Basin, parts of the Georgetown Inlier not covered by earlier BMR-GSQ mapping, Broken River Embayment, Burdekin Basin, Lolworth-Ravenswood Block, Campwyn Block and Anakie Inlier. The 1:250,000 sheets covering these areas of interest are shown in Figure 1 including those already completed, those in progress and those planned for future investigation.A flow chart showing the various phases for RGMP projects is shown in Figure 2. Data collection has two facets: (i) field recording and (ii) office work including air photo interpretation, study of company reports, literature research, petrography and various laboratory studies. Two main strands of information collected are represented by a data base and compilation sheets. Compilation sheets are generally at 1:25,000 scale and are available for purchase. The current data base is very fragmentary and can be accessed only by direct contact with the relevant geologist or via written reports. A more accessible field data base is in the process of being introduced this year; this field data base (REGMAP) is based on standardised data recording and computer storage.

Jan 1, 1986

This paper briefly discusses the negotia- tion of the more important provisions in agree- ments for exploration and mining rights with Pacific countries. LAND RIGHTS Land rights are complicated and sometimes controversial in many of the Pacific countries. In some countries, a company will have to deal with land owners directly; in others, the government will act as intermediary. Inevit- ably, a company will have to deal with both. Mining companies need to be sensitive to the culture and particular interests of the land owners and of their history in defending their rights. The issues are too complicated to be dealt with here. Some mining companies have spent, and will continue to spend, considerable time trying to understand them. It will " require patience, perseverance, sensitivity and unflagging optimism. The better advised companies will ensure that their local repre- sentatives get to know the land owners, under- stand their concerns, and will pursue a policy of keeping them informed on a regular basis of all of the company's activities and proposed activities. Good community relations are the keystone for good mining operations in the Pacific. Most countries will require the submission of an environmental impact statement so that they will know in advance what effects a pro- posted mining operation are expected to have on the environment and how it is intended to deal with them. They will also want to approve the company's environmental reclamation and rehabilitation plan. Let's face facts right away - mining, by its very nature, is not going to improve the environment. There will be waste discharges, emissions and deposits. They will affect the land, air and water and hence human, marine and animal life and vegetation. There will be sounds and odours and the esthetics of mining operations, though perhaps pleasing to geolo- gists and mining engineers, will not please Others.

Jan 1, 1987

By Dyne GD

From experience in the design and operation of power station combustion facilities in most mainland Australian States, involving a wide range of black coals and lignites, and in the specification and procurement of coal supplies for power station use, techniques for the optimisation of coal resource development and power generation utilisation have been developed to ensure compatibility between characteristics of the selected coals and power station design. These techniques include computer data bases for resource data handling and computer simulation of coal-fired boilers for determining coal property cost effects. Data Base Systems allow results of coal analyses to be efficiently handled, to assist in the review of the relevance of resource data to the coal sections proposed to be mined and the coal fractions proposed to be marketed. Data Base Systems also facilitate the marshalling of coal quality data into basic utilisation format to enable a proper utilisation review and analysis of the certainty and scatter of coal properties. Computer simulation of the effects of different coal properties on the capital and operating cost of power stations is achieved by establishing conceptual design parameters of the major items of plant to relate the variations in coal specification to equipment size and type. Variations in power station budget costs can then be determined using the computer model for variations in coal specification.

Jan 1, 1983

By T Baumgartl, B Richards

Covers on waste rock and tailings remain the primary choice for closure planning where the purpose is to create an environment where water ingress into reactive material can be controlled and/or prevented. In semi-arid and arid environments, dry cover systems are the preferred option with the design intention to absorb rainfall and to prevent deep drainage. Although the average amount of rain typical for semi-arid environments is relatively low and evaporative demand is high, the seasonal and annual distribution may vary greatly. Rocky substrates are often the only choice for the construction of covers due to economic constraints or availability of suitable materials. While the water holding capacity may be suitable for the application of a dry cover design in arid and semi-arid climates, some of these covers bear the risk of preferential water flow when rain events are intensive or occurring at high frequency. The objective of this presentation is to demonstrate the occurrence of preferential flow through rock containing dry cover systems. A regional classification for the applicability of dry covers is attempted to delineate those regions of Australia where the characteristic of the rainfall pattern increases the risk of failure for dry cover designs. CITATION:Baumgartl, T and Richards, B, 2016. Rainfall patterns rather than climate classification control cover design for closure, in Proceedings Life-of-Mine 2016 Conference, pp 89–92 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

The dielectric properties of practically all oxide and sulphide ore minerals are such that they heat rapidly when irradiated with microwaves particularly at the standard frequency of 2450 MHz. The presence of carbon or low rank coal mixed with the minerals still further enhances the heating rate. Amongst the patented technologies being investigated are: (i) the direct reduction of oxides with or without carbon included in the pellets or briquettes; (ii) microwave precursor heating of composites ahead of smelt reduction; (iii) microwave smelting of ore or concentrate mixtures with carbon, sometimes assisted with oxygen. Microwaves appear to stimulate endothermic reduction reactions as readily as they do exothermic oxidation reactions. Being a method of achieving "bulk" heating, composites or columns of ore-char blends rapidly heat throughout rather than from the outside inwards as in conventional heating. The microwaves of themselves do not generate any gas - the only gases to be cleaned are the products of reaction in the composites or blends, plus the products of oxygen smelting. In the case of sulphide composites, depending on the quantity and type of low rank coal or char present, sulphur may be eliminated, and collected, in the elemental form. Furthermore, reactions seem to take place at lower temperatures than in conventional smelting but no doubt at the "points" where actual reactions are taking place the atomic or molecular vibrations are such as to satisfy the laws of thermodynamics. Examples are given of the production of unusual products of smelting sulphide concentrates and also the alloys produced from refractory minerals such as chromite and ilmenite. The techniques have been used to produce products with as wide a range of melting points as relatively pure tin and tungsten-molybdenum alloys. Special equipment is being designed and evaluated for these new fields of pyrometallurgy.

Jan 1, 1989

By P B. Hills, R J. Walton

Narrow vein tabular orebodies are prone to mining induced seismicity. The Tasmania Mine is a complex example of a seismically active tabular orebody, where the contrasting material properties of the host strata and of the orebody itself, serve to exacerbate the seismic response. Analysis of a continuous record of seismicity over a period of seven years has provided significant insight into the fundamental mechanics of the rock mass. Understanding seismicity to permit safe extraction of the orebody has been enhanced by instrumentation of rock mass behaviour in response to mining and mining induced seismicity. It is the purpose of this paper to explore that understanding in respect to the adoption of an alternative down-hole Avoca stoping method for use in particular circumstances.Intensive instrumentation of the Tasmania Mine over a period of four years has provided insight into the behaviour of the rock mass in response to extraction of the narrow vein orebody it encompasses. A range of instruments have been installed in clusters or single installations in order to measure changing stress conditions and the impact of those changes on the rock mass and the reinforcement system.Instruments are often installed in very close proximity to active production stoping. While it has been possible to observe the impact of the mining and mining induced seismicity at very close quarters, instruments installed in these locations are vulnerable to damage and consequently, the level of instrumentation is high. Instruments are continuously logged, typically on a six hourly basis coinciding with the end of regular blasting times. The response of the instrumentation to changed rock mass conditions is considered against the background of development and production blasting and against the seismic record to assess the viability of downhole Avoca stoping.CITATION:Hills, P B and Walton, R J, 2012. Continued observations of rock mass behaviour in response to stoping at the Tasmania mine, Beaconsfield, Tasmania, in Proceedings Narrow Vein Mining 2012 , pp 169-178 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012