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The mineral sands industry in Australia can contribute much more sig- nificantly to economic development beyond the year 2000 by increased production of constituent minerals such as ilmenite, zircon, rutile, leu- coxene and monazite from existing and new resources, and especially from downstream processing to intermediate and finished products based on these resources. The end-use areas for mineral sand-based products include those products whose demand is tied to general economic growth, such as paints and plastics, and refractory bricks for the steel industry. High techno- logy applications such as zirconia ceramics and super-magnets are indica- tive of new developments in technology which provide considerable scope for expansion at higher rates than overall western world economic growth. An optimistic outlook for the industry is outlined, based upon a brief review of opportunities.

Jan 1, 1988

Initial coal production at Ulan was solely from underground mines. A significant increase in demand for steaming coal in the late 1970's emphasised the need to further expand production and led to the development of the open cut mine which commenced commercial production in June, 1982.During the initial stages of mine planning, feasibility and cost studies were undertaken to determine the most suitable method for coal haulage from the pit. The comparison between a conventional truck haulage system and an in-pit crushing system using a mobile crusher and moveable belt conveyor haulage confirmed that the mobile crusher and conveyor system was superior in every respect for the Ulan mining operations.Technical features and design parameters for the major items of equipment are outlined as well as operating, manning and performance assessments. Minor equipment problems were encountered during initial operation but these have since beenrectified and the plant is now capable of exceeding the design production. Maintenance and energy costs are considerably lower than originally estimated and production efficiencies are continually improving as operators develop new techniques and procedures in the handling of the equipment.

Jan 1, 1985

Comalco's Bell Bay smelter produces some 94 000 t.p.a. of primary aluminium in the form of foundry alloys, extrusion billet and rolling blocks. The extrusion billet and rolling block are produced by a process, in which molten aluminium is poured into an open ended water cooled mould of the required shape. The bottom of the mould is initially closed off by a dummy or starting block. Primary cooling takes place at the mould wall and secondary cooling is achieved by direct water sprays onto the out side shell of the product. Careful preparation of the molten alumin- ium is essential if stringent alloy specific- ation limits are to be met. Optimum casting temperature must be maintained within a narrow range and metal cleanliness is important to ensure a consistent product. Increased demands of recent years for larger product and higher standards of surface quality and dimensional control have been instrumental in forcing improvements in furn- aces, casting machines and in mould and dummy Doq,

Jan 1, 1977

By M Rimes

This paper describes a technique to predict achievable head grades and likely variances from target grade for the Shovelanna Iron Ore Project, in the Pilbara region of Western Australia. The block model from which the production schedule is produced was created from a wide spaced drilling program and was classified as an Inferred Resource under the JORC Code. Ideally, production schedules and target grades would be determined using a combination of Proved and Probable reserves. However sometimes it is necessary to consider the requirements of potential off-take parties who have specific grade tolerances. A technique is needed to simulate mining sequences and grade variations early in the planning process, using an æexplorationÆ block model rather than the normal æminingÆ block model. Marketing contracts require examination whether the target grade {Fe, P, SiO2, Al2O3 can be kept constant, or must be revised during the life of the mine. A model (written in ExcelÖ using Visual Basic macros) develops a feasible, close to optimal, mine plan from block model data. Cut-off grades for minable ore are chosen. The model evaluates ore tonnage, grade and stripping ratio against depth. Outputs at this stage include plots of slices through the orebody, at nominated x, y and z coordinates, showing ore grade, waste, drill hole locations and topography. The model then searches for a feasible satisfactory mine plan. The initial grade target is the average for the identified ore blocks. The available block list (ABL) at any time is the set of ore blocks, any one of which can be mined without removing any other ore block. The entire initial ABL has an unacceptably large ætotal grade stressÆ, defined as [(Grade-Target)/Tolerance]2, summed over the four relevant minerals {Fe, P, SiO2, Al2O3}. The model trims the ABL, removing the block most harming the total stress. Trimming is repeated until the total grade stress reduces to an acceptable level. The trimmed ABL defines the first mine campaign. Removing the trimmed block set, a second ABL is exposed, which is again trimmed and mined. The process is automatic: a few seconds computation provides a complete mine plan. Re-running the model with adjusted grade limits quickly shows whether a uniform target can be achieved or whether the target must be modified during the mine life.

Jan 1, 2007

By Jiang G

The Chinese Central Government attaches great importance to the development of its coal industry. Besides carrying out the policy of simultaneous development of large, medium and small coalmines,the main strategy is to gradually modernize coal mining areas and coalmines and to increase the output from individual coalfaces. There are particular implications, processes and main experiences of coalmine modernisation in China.Ensuring a coal output of over one M tonne/yr from one coalface is a very complicated system-engineering project which deals with a wide range of problems. The most important measure used for achieving an output of over one M tonne/yr from a single coalface is the analysis of affecting factors on coalface production by means of the theory c reliability. Thus, as far as possible , the production stoppages caused by mechanical equipment failures and other factors are avoided, the equipment recovery rate is increased and the working hours of shearers are extended so as to ensure a high output and high efficiency.

Jan 1, 1991

The Abra mineralized body is regarded as a significant new style of mineralization for its environment. It is a blind polymetallic deposit, located in the Bangemall Basin of Western Australia. It was discovered by Geopeko in 1981 by diamond drilling a coincident magnetic gravity target, which revealed a large low grade epithermal Fe-Ba-Pb-Ag-Cu-(AuW) deposit, hosted by chemogenic and clastic sedimentary rocks, overlain by 200-500 m of clastic sedimentary rocks, of Middle Proterozoic age. The mineralization occurs as an upper stratabound phase, and a lower vein "stringer" style phase within a pervasive chlorite alteration envelope.

Jan 1, 1987

By Guo H

The importance of using disc cutters for rock excavation is reflected by their wide application in hard rock cutting machines such as tunnel boring machines and raise borers. The forces involved in the cutting process are those due mainly to thrust and rolling forces and are greater than that required by cutting picks. An interesting feature of cutting with discs is the formation of surface crushing, surface and sub-surface chipping and primary crack formation. Experimental, as well as analytical, work has been carried out to determine the optimum spacing between the disc cutters to control primary crack orientation. Wedge bit indenters were used to simulate disc cutters. The paper concludes by proposing a new approach to rock excavation by hybrid cutting based on controlling the primary crack Orientation.

Jan 1, 1992

By D A. Williams

The conventional method of transporting mine tailings from a process plant to a tailings storage facility (TSF) is in the form of a low to medium density1 slurry, which can be pumped using centrifugal pumps. Over the past several decades, therefore, mine operators have generally adopted this default approach. There are, however, some convincing arguments why consideration should be given to thickening the tailings slurry to a higher density paste consistency. In particular, the minimisation of environmental impacts, the reduction in water consumption and the cost savings relating to TSF closure make paste an attractive option for the life of mine tailings disposal. There are several environmental impacts that are associated with a conventional slurry TSF, such as land sterilisation, aesthetics, dust, seepage and acid mine drainage. Some of these impacts, such as dusting, may be difficult to mitigate while the TSF is in operation. Others can be influenced by adjustments made to the tailings slurry density at the plant. Unplanned fluctuations in slurry density and/or viscosity can have a significant influence on TSF performance and can exacerbate the environmental impacts relating to the facility. Relatively minor changes in the solids content of the slurry can affect tailings beaching behaviour, degree of segregation, position of the phreatic surface, amount of freeboard, consolidation behaviour, placed (settled) density (and hence TSF capacity) and in situ strength of the tailings. Paste is a non segregating slurry and many of these effects can be minimised at the TSF when the tailings slurry is thickened to a paste. These improvements are manifested by reduced seepage, flexibility in selecting an appropriate final landform, ability to rehabilitate progressively and reductions in plant water usage. It is possible to minimise environmental impacts of a TSF through the use of tailings paste. Ideally the paste production plant should be part of the initial design of the process plant. However, significant benefits can be gained by adding a paste production plant at some time later in the operational life of the mine to reduce environmental impacts and facilitate an environmentally acceptable TSF closure.

Jan 1, 2002

By Harper B

The mining industry has developed a comprehensive view of the need to have production personnel well trained in the use and maintenance of mining equipment. A strong commitment from the industry to this view has been instrumental in creating an efficient, profitable and productive industry based on modem production processes, sophisticated equipment and a multi skilled workforce. As the industry continues to develop, and the skills and knowledge needed by productive workers continues to expand, the training processes adopted by the industry will need to develop in parallel, not only making use of the latest advances in learning theories, instructional design and technology, but also using these knew ideas in more efficient ways.

Jan 1, 1998

By T Napier-Munn, D J. Bradshaw, M Chauhan, L Keeney

An important aspect of geometallurgy is quantifying mineral processing attributes, which leads to improved orebody understanding. One of these attributes is flotation performance. Several methods have been developed as indicators for flotation performance, including batch testing leading to kinetic information and the standard grade-recovery curve. This paper makes a preliminary statistical comparison between a newly proposed geometallurgical batch flotation procedure and the æstandardÆ batch flotation test commonly used to measure flotation performance in the laboratory. The new test uses much less material than the standard test, and is much faster. It is concluded that the new method follows the final recovery of the standard method well, suggesting that it will be effective in reflecting ore variability for geometallurgical purposes. Comparison of the methods based on the full grade-recovery curve shows less agreement, but this may be due to the fact that the curve is sensitive to the particular experimental set-up and conditions, which make such comparisons quantitatively challenging. Further development work is therefore planned.CITATION:Chauhan, M, Napier-Munn, T, Keeney, L and Bradshaw, D J, 2013. Progress in developing a geometallurgy flotation indicator, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 201-206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By T C. Hughes, R Hughes

Ausmelt has developed and commercialised high temperature reactor technology that has been applied to waste processing in the form of a catalytic waste converter (CWC). Ausmelt Technology uses a top submerged lance system within a versatile converter containing an oxidised molten siliceous slag. Metals and other valuable products can be extracted from wastes for recycle into the community. Non-valuable components such as toxic organochlorinated compounds are destroyed and prevented from reforming. The slag produced is inert and can be safely used in building and concreting. The CWC can be applied to practically all types of wastes and examples from Ni-Cd batteries to toxic wastes are discussed. Additional benefits can be derived from large-scale operations if the surplus heat generated is exploited to produce steam and electricity.

Jan 1, 2000

By Hayward N, Sutherland D, Wilkie G

A pilot plant study has been made of the liberation characteristics of a nickel ore under different milling conditions. A series of runs were made ranging from fully autogenous grinding to semi-autogenous grinding with a ball load of 8%. The mill products were sized and assayed then analysed by QEM4SEM. This enabled a full liberation analysis to be carried out to see whether the autogenous grinding leads to improved liberation by promoting selective breakage. Though it is frequently claimed that fully autogenous grinding yields superior liberation this could not be detected in the present study.

Jan 1, 1991

By M Clay, J Dunlop

Thermal and metallurgical coal mining in Queensland has resulted in mines which contain voids due to open cut mining. While there are several proposals for greenfield coalmines or expansions to existing operations, many existing open cut coalmines are reaching maturity and most will leave one or more residual voids in place. The rehabilitation of mine voids is challenging. Water held in voids will evaporate over time leaving solutes to concentrate. This is likely to lead to poor water quality with limited practical use. The most basic practices to rehabilitate voids have historically involved stabilising the high and low walls, bunding to provide flood protection, and preventing public access. Regulatory reforms for mine rehabilitation were introduced in Queensland as part of the Mineral and Energy Resources (Financial Provisioning) Act 2018, and aimed to strengthen progressive rehabilitation planning, limit risks to the environment and improve outcomes for local and regional communities. Under the reforms, the goal for rehabilitation of voids is to achieve a safe, stable, and non-polluting landform, which can sustain a post-mining land use (PMLU). The reforms also introduced a requirement to describe rehabilitation of mined land in Progressive Rehabilitation and Closure (PRC) plans, replacing the description of such plans in Environmental Authorities (EAs). The reforms are not retrospective and recognise historic approvals for voids, meaning established voids will remain in the landscape as non-use management areas (NUMAs). The objectives of this study were to outline historic void rehabilitation planning practices, describe water quality limitations of Queensland mine voids and identify possible opportunities for improved planning

Aug 2, 2023

By Nickson NM, Lancucki CJ

X-ray diffraction and differential thermal methodshave been used to determine the mineralogy of some clays used by the heavy clay industry in the Adelaide area. A detailed analysis has been made of the mineralogy and. particle size distribution of eighteen samples from beds' in two pits in~the Recent seaiinents in the Adelaide plains, of six white clays.: developed from the weathering of the Adelaide series of `sediments and, of ,four -Recent alluvial clays from a pit in the Mount Lofty ranges south of Adelaide. Structural clay products 'in the Adelaide area are manufactured from mixtures of these clays:, so the mineralogy and particle size distribution have been determined of eighteen clay mixtures used to make red bricks, cream bricks,. facing bricks, pipes and tiles. Knowledge of this mineralogy is important in understanding the ceramic behaviour of the clays.

Jan 1, 1963

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

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

Jan 1, 2009

Miners and mineral explorers are concerned at the increasingly hostile environment being generated towards their industry and their profession. There is little official or public recognition that the mining industry is essential for the maintenance of the country's standard of living; a large part of this hostile feeling is caused by the assumption that mining destroys large tracts of our attractive countryside. This paper presents a historic review of the impact on the countryside of the major land using groups commencing with the Polynesian migration. European farming practices, subsequent expansion of the urban dweller and the land management practices of the two Government Departments, Lands and Survey and New Zealand Forest Service who between them control half of the total land area, are discussed. Estimates of total land area to date, directly and indirectly affected by mining have been calculated and a broad estimate of 18 000 ha or 1/1500 of total land area is indicated; current annual mineral production requires some 240 ha. These gross areas take no account of subsequent land rehabilitation, its improvement upon the original in some cases and the recreational, historic and aesthetic areas gained. Comparisons are then drawn with some current land practices in New Zealand.

Jan 1, 1977

By D Sidea

There has been increased focus in Australia on large diameter raise boring for ventilation shafts and orepass excavation in good quality, brittle, highly stressed rock. As mining in many parts of Australia progresses to deeper levels, more vertical openings are being excavated in highly stressed ground conditions. However, whilst shafts have been successfully raise bored in highly stressed rock, it is often at a significantly increased risk of loss or damage to inhole equipment. It is important for both mine owners and contractors to have an appreciation of these risks at the planning and tendering phases of raise boring contracts. This paper provides an understanding of the risks associated with large diameter raise boring and a review of methods to predict failure in highly stressed rock.

Jan 1, 2005

By Hayba DO

Metal-rich slurries discharged from excess-enthalpy geothermal wells at Kawerau (NZ) indicate that an efficient ore precipitation mechanism operates in some feedzones. In our conceptual model, which takes into account the relative permeabilities of liquid and gas phases in boiling fluids, a metal-precipitating liquid phase is effectively immobilised along boiling fronts, leading to the formation of highly concentrated ore. Chemical equilibrium and heat/mass transport modeling demonstrate the general applicability of this conceptual model to hydrothermal eruption environments.

Jan 1, 1995

By R Smart

This paper examines the longer-term predictive capacity of the GAMSPATH computer program (developed by the Alberta Research Council) for a waste rock (sample MS) obtained from the Kaltim Prima Coal (KPC) mine, Kalimantan that contained significant framboidal pyrite. The model was refined by comparison with the net acid generation (NAG) and column leach tests to provide a basis for calibration of the model for both short term and longer-term reaction trends. The oxidation of pyrite during the kinetic NAG test using H2O2 provides oxygen directly at the mineral surface, generating a measured oxidation rate for pyrite of 1.16 + 10-6 mol m-2 s-1, whereas the oxygen diffusion limited rate in the leach column air equilibrated reaction was of the order 10-8 mol m-2 s-1 as calculated from the GAMSPATH thermodynamic database. Results indicated that the oxygen derived from hydrogen peroxide had to be included as a reactant (eg a reacting mineral) in the simulation to account for the direct availability of oxygen at the sulfide mineral surfaces. Optical investigations identified the proportion, particle size, and surface area, of framboidal and euhedral pyrite in sample MS. The reactive surface areas of the two morphologies were very different (eg ratio: 5:1). To manage these two different pyrite morphologies the GAMSPATH thermodynamic database was updated to include framboidal pyrite, with similar thermodynamic properties and oxidation rate to euhedral pyrite but with a particle size based on the size of the individual internal framboid microcrysts. This modification, with framboidal pyrite reaction based on the size of its microcrysts produced results that correlated well with the kinetic NAG and column leach test results when the measured (kinetic NAG test rate) and calculated (column test rate) pyrite oxidation rates were employed. This provided some confidence that the model could be extrapolated to indicate longer-term geochemical reaction trends.

Jan 1, 2003

By J Harmse

This paper deals with the modernisation of the brakes on an electrically coupled Blair multi-rope hoist and covers the removal of the old calliper brakes and hydraulic control system, and its replacement with brake discs, disc braking units and hydraulic control systems. The paper covers the braking requirements of the hoist, which is made up of two electrically coupled single-drum hoists, together with the theory behind the choice of brakes and control systems supplied. The paper also covers the project logistics that were required in order to install and commission the new brakes and control systems with the minimum disruption to production on the only rock hoist on a major production shaft. Items covered include the modifications to civil works, pre-installation of bearing lubrication systems, brake discs and hydraulics and the interfacing of the new hydraulic control system to the existing electric control system. It had to be designed to be compatible to a new electric drive and control system due for installation at the end of 2005.

Jan 1, 2005