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By P Gnnther, A M. van Niekerk

Coal mining operations in the Upper Olifants River Catchment in the Mpumalanga Province of South Africa are challenged with the increasing production of excess mine water that cannot be fully managed by existing practices of pollution control at source, recycling, and reuse on mining sites, storage and limited release to the natural water course. In contrast to this, the Olifants River Catchment is experiencing water stress and insufficient water is available to satisfy all water quantity and quality requirements for future industrial and municipal growth. It is estimated that the catchment has a deficit of 192 million m3 per annum if the reserve water requirements are taken into account. The future increased water requirements can be met by water transferred to the Olifants River Catchment from adjacent catchments. The cost of transferred water is likely to be substantially higher than the current cost of water supplied to local municipalities, commerce and industry. BHP Billiton and Anglo Coal Corporation are working together to jointly implement water management strategies that will contribute to the achievement of in-stream and dam water quality and aquatic objectives for the catchment. Consideration is now being given to the treatment and beneficial use of excess mine water. This will inaugurate a new era for the coal mining industry in South Africa, in which a pollution threat to the water resources in the Upper Olifants River Catchment is converted into a water source for beneficial use. Three potential mine water reclamation and reuse schemes have been identified and this paper details the technical, institutional, legal and financial considerations in the implementation of these schemes.

Jan 1, 2006

Nickel-iron sulphide mineralization at Nepean, Western Australia occurs within a small Archaean greenstone outlier in granite south of the main Coolgardie greenstone belt. Individual sulphide ore bodies are situated near the foot- wall contact of simply-differentiated en echelon ultramafic sills that have intruded a sequence of sulphide-bearing metasediments and amphibo- lites. The paper describes a detailed section through the No. 2 ultramafic sill and its associated sulphide ore zone, which gave Metals Exploration N.L. the first significant nickel discovery in the Nepean area in 1968. The sill is variable in thickness up to 30 m along a strike length of 600 m, and is truncated to the north by pegmatite intrusion and pinches out to the south. The body has border zones of pyroxenetic composition, now represented by felted aggregates of chlorite and amphibole, and a central peridotitic core in which olivine and orthopyroxene are concentrated towards the base. Textures within the peridotite are dominated by large lath-shaped olivine grains and their serpentine pseudomorphs, which delineate triangular areas composed of talc, chlorite, and amphibole. Orthopyroxene occurs in large ovoid patches and is often replaced by Talc.

Jan 1, 1973

By P Hollings, J Holliday

Porphyry copper, gold and molybdenum deposits form in subduction-related settings in association with calc-alkalic or alkalic magmatism. Hydrothermal alteration assemblages are zoned, with potassic cores and propylitic haloes overlain by extensive domains of clay alteration and silicification (lithocaps). Copper sulfides, gold and molybdenite typically occur in veins or hydrothermal breccias, and less significantly as wall rock replacements. Epithermal deposits may form above or to the side of porphyry systems, and may be juxtaposed into the core of a porphyry deposit if rapid uplift and exhumation occur through the life of the magmatic-hydrothermal system. Volcanichydrothermal breccia pipes (ædiatremesÆ) commonly form late in the life of a porphyry system. They may contain clasts of porphyry-style mineralisation, and can host significant epithermal gold resources. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

Results from current NERDDC funded research into the geotechnology of highwall trench mining methods have clear implications for mine planners in the areas of blast design, trench shape, location of the surcharge spoil and remnant coal pillar design.Adoption of successful smooth wall blasting techniques not only removes safety hazards from the trench face, but limits development of bedding partings at the seam contacts that interrupt the smooth transition of stress across the coal seam.

Jan 1, 1992

By H P÷llmann

Calcium aluminates, calcium aluminate ferrate and calcium aluminate sulfate were synthesised by solid-state reaction, sol-gel method, a self-combustion method and by a polymeric precursor process. For chemical sintering methods the base chemicals CaO, CaSO4, Al2O3 and Fe2O3 were used. As precursors for sol-gel synthesis metal nitrate hydrates and Al2O3-Sol were used. In order to synthesise pure phases by a self-combustion reaction glycine was used as fuel and nitrates as metal components. In the polymeric precursor process metal nitrates and diluted H2SO4 were used as metal components and the resin was made using citric acid (C6H8O7) and ethylene glycol (C2H6O2). Precursor phases synthesised by these different methods were sintered step-by-step in order to investigate the crystallisation. Further on single phases were hydrated and their hydration behaviour was studied by heat flow calorimetry, X-ray diffraction and cryo-transfer scanning electron microscopy. Due to the different synthesis procedures different hydration reactions and microstructures of the phases will be shown.

Jan 1, 2008

By Totterdell JM

The Permian-Triassic Bowen Basin and the Jurassic-Cretaceous Surat Basin evolved in a backarc tectonic setting behind an active convergent plate margin in eastern Gondwana. Several extensional (Early Permian; Eocene) and contractional (mid- Permian; Early Triassic; Middle-Late Triassic; early Late Cretaceous) intraplate deformational events are recognised in the basins. These can be correlated with similar events in the New England Orogen that was being deformed in the Late Permian- Late Triassic as a foreland thrust belt. The intraplate deformations were probably the consequence of plate interactions, including the accretion of terranes, at the ancient active plate margin, remnants of which now occur in New Zealand.

Jan 1, 1995

Iron ore in the Pilbara Region of Western Australia varies in composition giving iron ore a range of densities. An accurate density figure of the material leads to accurate calculations of production throughput. Density studies of two separate iron ore mines were conducted in the Pilbara. Procedures and results are reported here.The Pilbara Region of Western Australia has a number of iron ore operations. Two mines have conducted density studies of their materials. The purpose for the studies was to determine an accurate in situ bulk density that could be applied to volume and tonnage calculations of the operation. It was identified that density was one culprit causing calculation variations. Density is an important figure used to estimate ore reserves, equipment requirements, production rates and indirectly costs and sales revenue. One study was conducted at Rio TintoÆs Robe River Mine based near the town of Pannawonica. Its Mesa J orebody is currently being mined and is a low-grade deposit of goethite and hematite (Burnham, 2003). A separate study was conducted at BHP BillitonÆs Yarrie Mine situated north of Newman and east of Pardoo. Its orebody consists of high grade formed by a supergene enrichment of cherty material and a burial metamorphism to produce hematite (Richardson, 2002). The method used to determine density was by large-scale samples using the pre-mining in situ volume of the material and the weight in tonnes after mining.

Jan 1, 2003

By D P. Telionis, P P. Vlachos, R-H Yoon

Industrial processes involving multi-phase flows such as flotation require understanding of the relationships between bubbles, solid particles and the flow. Modern experimental tools are employed in this effort to measure with great accuracy the basic features of the motion of all three phases in turbulent flow. We employed a unique digital particle image velocimeter (DPIV) that can record with great accuracy and kHz temporal resolution, velocity vectors of all three phases, namely the fluid, the solid particles and the air bubbles. The interaction of these three phases was studied in homogeneous isotropic turbulence generated by cylindrical grids. Particles and bubbles were released into the turbulence and the motions of the three phases were monitored. The experimental results obtained in the present work were compared with the predictions of the models published in the literature.

Jan 1, 2005

The Lower Palaeozoic Woolomin Association is composed of chert and jasper (often radiolarian), siliceous argillite, the mafic volcanics with associated hyaloclastites, and occasional greywacke and limestone lenses. Several "Cyprus-type", conformable pyritic copper (+/- zinc and cobalt} sulphide lenses are spatially related to individual mafic volcanic units and manganiferous chert and/or jasper. The Association has been interpreted to represent an oceanic crustal remnant generated either in an island arc environment (Herbert, 1981) or at a divergent plate boundary (Scheibner and Glen, 1972; Leitch, 1974a, 1975) later to be obducted, or tectonically emplaced, into continental crust; the adjacent Peel Fault was considered to be the palaeo-obduction zone (Scheibner and Glen, 1972) and the associated alpine-type mafic/ultramafic complex, an ophiolite (Crook and Felton,1975).

Jan 1, 1990

Roller seed screens were installed at The Broken Hill Proprietary Company Limited (B.H.P.) Whyalla pellet plant to replace vibrating screens on the green ball circuits. The installation of roller screens was justified by improving the sizing of the green balls. This improved sizing increased the yield of fired pellets produced from green balls thus decreasing the fuel consumption. The fired pellet sizing was improved also. This paper discusses the configuration of the roller screens installed at Whyalla, quality of green balls produced, advantages of roller screens compared with vibrating screens and future development of roller Screens.

Jan 1, 1984

By Wu H. W, Jones S. J

Australia wide, over 40 fly-in/fly-out mining operations and other forms of long distance commuting now exist, with coverage of about 5000 employees. The substantial majority of these operations are in Western Australia, with some mines also located in Queensland and the Northern Territory. In recent years new large-scale mining operations have adopted the fly-in/fly-out approach and it is important to note that no new mining towns have been constructed in Australia since the township of Roxby Downs was built in the late-1980s to service the Olympic Dam mine. An examination of fly-in/fly-out mining operations in Australia has been undertaken. A detailed survey undertaken in 1990 has been reviewed and another intensive survey undertaken to establish emerging trends. Results from both company and individual employees point of view have been analysed. A section examines the views of professional employees and the influence of fly-in/fly-out on career development. Bus-in/bus-out coal mining operations are emerging in Queensland's Bowen Basin. These operations commute their employees into the mine site for compressed working schedules while the mine employees' families are domiciled in regional cities such as Mackay. A review of the issues associated with the development of long distance commute coal mining operations in Queensland's Bowen Basin is performed and two case studies examined.

Jan 1, 1997

By G D. Carman

White Rock is a reduced tungsten-tin skarn deposit near Rye Park, New South Wales. This abstract summarises the depositÆs mining and exploration history, and current exploration by Paradigm Metals Ltd targeting an economic resource at the deposit. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By A Sinuhaji, R Poedjono, G Flumerfelt

PT Freeport Indonesia is currently building the DOZ mine. It is a 25 000 tonne/day block caving operation which is scheduled to reach designed production levels by the fourth quarter of 2002. This paper describes some of the issues and challenges faced by the operation when introducing a new undercut method part way through the project. Advantages and disadvantages are discussed as well as the expected benefits of the new method.

Jan 1, 2002

By I Mason, G Turner, J Hargreaves

One of the key objectives in production from any mine is the minimisation of ore loss and dilution. This can only be achieved when the distribution of ore within the mine is known. The distribution of ore is usually evaluated from a combination of drill hole information and underground mapping data. Three-dimensional models of the ore distribution are then constructed by interpolating grades, contact locations and confirming these estimates through mapping. While the interpolation procedure can incorporate an understanding of the local geological conditions, it is an approximation and thus susceptible to some degree of ore loss or dilution. Naturally, such problems increase in areas of sparse geologic information or greater geologic complexity. Borehole radar offers an approach to decrease the interpolative aspects of modelling by providing a continuous image of some ore contacts. Borehole radar works by building a two-dimensional image of an ore contact from radio waves bounced off the contact from closely spaced positions along a borehole. This image can be imported into Datamine (or a similar design package) and incorporated into geological models of a given ore block. The results of a trial survey from the Mariners nickel mine at Kambalda are presented to illustrate the improved level of detail and accuracy that can be achieved through the incorporation of borehole radar into orebody delineation practice. Once implemented on a large-scale this technique has the potential to greatly increase the cost-effectiveness of long hole stoping at Kambalda, through increased ore recovery and reduced dilution.

Jan 1, 2000

By Ingham PD

Selection of equipment for a mining operation, such as Mount Isa Mines, requires certain parameters to be correctly defined. Management control is essential for monitoring, improving and future purchase of equipment. Some research is being done independent of supply manufacturers. Observations about future outlook are made.

Jan 1, 1982

A test model is presented for the simulation of dewatering by gas injection of a porous aquifer above longwall workings. A finite difference model used in the oil industry was modified to match the underground mining conditions. The model is suitable to cope with the problem of dewatering reservoirs of low transmissivity. After comparing more versions, it has been concluded, that the investigated dewatering method can be proposed under special hydrogeological conditions only.

Jan 1, 1988

By Koginmo V. I

The concentrator at Bougainville Copper Limited has an annual throughput of 48.2 million tonnes/year producing approximately 175,000 tonnes copper, 16.1 tonnes gold, and 50 tonnes silver. Conventional three stage crushing and screening are used to reduce run of mine ore to an average product d80 size of 6.7mm. The primary objective of the crush- ing plant is to provide a continuous supply of ore to the 12 primary grind- ing mills via an intermediate 300,000 tonnes capacity stockpile. Since ball mill performance improves with decreasing mill feed size, the crushing plant continually strives to produce the finest possible product for mill- ing. This has been achieved by increasing plant availability and total installed power, and improving crusher manganese liner life, screen cloth life, and plant operating practices. A recent innovation was the installa- tion of a 35 million tonnes/year preconcentration screening plant in Janu- ary 1987 to recover high grade fines from low grade run of mine ore types in which the mineralisation occurs preferentially along fracture planes in the parent rock.

Jan 1, 1988

This paper describes thick seam mining as practised at Westfalen Colliery, Redbank via Ipswich,in South Queensland. The author describes the develop- ment of the mine from conception to the time of successful operation and compares the two systems of mining adopted at the colliery.

Jan 1, 1976

By P Ireland, S Mitra, G Evans, A Wang, M M. Hoque

This work presents an experimental study of flow dynamics in a bubble column system (crosssection: 100 mm × 100 mm) using a non-intrusive optical technique with targeted application in a novel REFLUX™ Flotation Cell. The study had two aims – measurement of the bubble size distribution (BSD) and local energy dissipation rate in the system due to bubble motions over a low range of gas flux varied from 0.02 to 0.08 cm/s without impairing the visibility of the system. A central bubble plume was generated by injecting compressed air through a sintered glass distributor in quiescent liquid. Highspeed shadowgraphy imaging was performed to determine the BSD in the presence of surfactant (Sodium Dodecyl Sulfate (SDS) concentration ~ 10 ppm). The BSD exhibited a unimodal shape at different locations of the column for all gas flux cases. A non-intrusive particle image velocimetry (PIV) technique was used to quantify the flow field generated by the bubble motions, which was used to estimate the local energy dissipation rate. The local energy dissipation rate exhibited an increasing power-law dependency on the gas flux.

Aug 24, 2022

By Reid JG, Cutfield S

Considerable quantities of dissolved nickel are lost in the waste liquors from the QNPL nickel treatment plant. Cementation, precipitation and ion exchange techniques were investigated to reduce this loss. Ion exchange was the most successful of the procedures studied and a process for recovering nickel from stripped ammoniacal process liquors was developed in the laboratory and scaled up to plant flow volumes. The system developed uses a carboxylic ion exchange resin operated in a completely ammoniacal cycle. The regenerant is itself regenerable using existing plant, thus the only loss is the stoichiometric value of NH4+ required to displace the exchanged cations from the resin. Existing plant sand/anthracite filter beds have been adapted for use as resin columns containing 3 cubic metres of resin capable of treating effluent at a flow rate of 6000 litres/min.

Jan 1, 1978