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The Energy Authority of NSW has wide powers and responsibilities conferred by its Act which are pertinent to the State's coal industry and its development into the next century. With respect to coal, the broad objective is to maximise the benefits to NSW and its people derived from the State's coal resources. The initial focus of the Authority's coal-related activities in the late 70's and early 80's was on petroleum substitutes from coal. Research was supported, especially on hydrogenation, and the Authority participated in the Joint Australia/Federal Republic of Germany coal-to-oil feasibility study. It also co-ordinated a State Government initiative to involve the private sector in examining the possible establishment of a synthetic fuels industry based on Hunter Valley coal. With a short-fall in world-wide petroleum supply now seen as less likely for some years, the Authority is looking also at ways of working towards the broad objective in the field of coal utilisation on both domestic and export markets. Areas of interest include possibilities for using washery rejects, means of making NSW coal more competitive as an energy source, use of coal-seam gas and new or special technologies for burning coal. The future is expected to see renewed interest in producing petroleum substitutes, and coal - as the State's major energy resource - is seen as a strong contender as a basis for such an industry. Developments in coal-based power generation are also expected to have an impact, with advanced technologies having a possible place here as well as Overseas.

Jan 1, 1987

Perception has the unfortunate habit of becoming reality. Urban inhabitants unfortunately do not regard mining as a legitimate or desirable business, despite its contribution to Australia's export income (+A $8,000 million, being nearly a third of all exports); share of GDP (it is 4.5%); and the fact that its presence fills up all the empty spaces northwest of the Adelaide-Melbourne-Sydney-Brisbane crescent of inhabitation. The huge economic contribution of Australia's minerals industry, resulting from providing more than half of merchandise exports (Figure 1), is achieved by employing only some 2% of the national work force (Gaulton, 1997). Unfortunately, the minerals industry's critics generally oppose exploration on the basis that what you don't know will not hurt you. It is the 'do-not-confuse-me-with-facts' philosophy or 'ostrich syndrome', which somehow crudely assumes that mining practices have stayed in the style popular circa late 1800s. Somehow ignorance really is bliss for these idealistic believers, who are reminiscent of the members of the Flat Earth Society!

Jan 1, 1997

Close spatial relationships between the deposits of the Etheridge Goldfield (23 000 kg of bullion) and various regional geological and geophysical features suggest that genesis of the ore deposits was a multi-stage process that started with magmatic and metamorphic stages in the mid-Proterozoic, climaxed with structural and hydrothermal stages in the late Palaeozoic and terminated with an oxidation enrichment stage in the Cainozoic.This hypothesis permits classification of the Georgetown region into areas likely to contain deposits of the Etheridge type and those unlikely to do so; it is concluded that there is little scope for the discovery of extensions of this field.However, the stratigraphic interval between the postulated source rocks of the Etheridge field and stratigraphically higher host rocks of the Croydon field may contain disseminated replacement gold deposits of the Carlin type. The potential host (Pyritic carbonaceous, and locally dolomitic siltstone of the Candlow Formation) is locally faulted and cut by granitoids and the extension of a mineralised, long-standing zone of structural weakness.

Jan 1, 1981

By Mining Geophysics

Modern geostatistics has eliminated much of the guess-work in ore reserve estimation, and can calculate levels of confidence for the reserve estimate. Geological modelling software has brought about a revolution in the communication of complex geo-variables to mining engineers, metallurgists, surveyors and managers. Mine planning and scheduling can now avail itself of a veritable toolbox of enabling technologies.

Jan 1, 1994

Remote sensing, in general, is the recording of light and heat from a planet's surface within a certain range of the electromagnetic spectrum. For the Earth, systems capable of this recording are the MultiSpectral Scanner (MSS) and SLAR. The former is the recording system used in satellite and will be discussed in the next section. SLAR stands for Side Looking Airborne Radar. This device sends invisible radar waves which illuminate the Earth's surface. The reflected waves are subsequently recorded as images. The system can operate through darkness and dense cloud cover, and is particularly suited for the study of geological structures at both large and small scale (Wayland 1976). Remote sensing techniques are now widely being made use of in mineral exploration, especially for those last remote 'sanctuaries' where geological data are meagre or non-existent. For places like Borneo, West Irian, the Amazon Basin etc. remote sensing, in the form of both satellite imagery and SLAR, is of considerable help, in fact more often than not the only help, to delineate geological provinces, geotectonic domains and meaningful lineaments. In the case of New Zealand, well made geological maps at scale 1:250 000 by the Geological Survey are available to the public and these provide useful preliminary grounds for the selection of target areas. However, even in this case LANDSAT imagery can be of aid as will be shown later.

Jan 1, 1977

By MáAndrusiewicz, M M. Hilden, M S. Powell, P D. Kay, B Foggiatto

Circuits with unconventional and potentially more complex designs are predicted to become more common in the future as plant designers and operators look to process ores more efficiently. Ideas have been presented on how circuit design may be changed to utilise todayÆs technology to address tomorrowÆs challenges (Powell and Bye, 2009; Powell, Benzer and Mainza, 2011a). High pressure grinding roll (HPGR) installations in various configurations; application of preconcentration plants eg sorting, magnetic or gravity separation; and preweakening devices eg microwave processing; are all examples of technologies having the potential to deliver a significant reduction in comminution energy for ores amenable to these processes. Not only will future novel circuits contain equipment for which models are not as well developed (if at all), many will likely require the ability to respond to variations in feed, and interact with geometallurgical models requiring process adjustments when the ore characteristics change.In order to confidently simulate more complex circuits and accommodate variations in feed type, a significant advancement in modelling and simulation capability is required. This includes dealing with multiple components in the feed, accommodating different competencies of ore, utilising physical separation opportunities and tracking the grade reporting along the different potential processing routes. Developing the means to simulate complex circuits has been a key priority of a collaborative group of comminution researchers working to solve these challenges.Simulations are presented utilising a new configurable simulation interface called the model developers kit (MDK). The MDK is designed to accommodate multi-components and incorporate new models under development. These will be used to demonstrate the potential of flexible circuit design, based on measured ore properties and equipment performance.CITATION:Foggiatto, B, Hilden, M M, Powell, M S, Kay, P D and Andrusiewicz, M, 2012. Simulation of flexible circuits, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 291-298 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

As this paper is being written primarily for perusal by milling workers, metallurgists and engineers, an attempt will be made to avoid the use of accounting technicalities. Its scope will be confined to a description of the methods employed in the collection of basic information for use in timekeeping, costing, and the compilation of statistics.TIMEKEEPINGEvery applicant for work is asked to furnish the following information, which is collected on a card (size 6 in. x 4 in.)...

Jan 1, 1922

By Mostyn G. R

An important problem in rock engineering is to control the properties of artificial rock. A compaction technique for casting artificial rock specimens with controlled properties is described, i.e. using a compression-testing machine to compress the mixture. Uniform density is necessary to achieve uniformity of properties of the specimens, and uniform density can be obtained by using the specific pressing method presented. Rebound and borax content are important to the technique and have been studied as well.

Jan 1, 1992

By Thatcher R

In areas where undeveloped land represents a scarce resource, an upgraded post mining land use can result in economic benefits to both the mining company and to the community. A study undertaken at Allied Queensland Coalfields Ltd's Aberdare Colliery located between Brisbane and Ipswich during 1986/1987, assessed the costs and benefits of developing the site following mining for grazing, forestry and residential uses. The proposed final land use plan comprised a combination of these uses which can be upgraded to higher valued uses once subsidence monitoring of backfilled opencut areas and dumps indicates that total settlement has reached acceptable levels. The study involved the documentation of existing site environmental parameters and the delineation of site opportunities and constraints. The unpredictable nature of settlement over backfilled opencuts and overburden dumps represents the major constraint to urban development on mined areas.

Jan 1, 1987

By Jardine G, Woodall C

The Henty Gold Mine, located in Western lasiuania use, uuiusatise solutions to effectively manage a mining operation in an environmentally sensitive setting and has been presented with several environmental awards. Fill is required as part of the mining method to provide passive ground support, minimise rock exposure and ensure maximum recovery of the small but high-grade orebody. The use of the whole portion of leach residue in the backfill reduces the surface tailing disposal requirements. Therefore, High Density Paste Fill (HDPF) has been selected as the most appropriate fill method to meet these objectives. Additional benefits include the minimisation of excess water from fill and the subsequent need for the collection and treatment of water and slimes. There are minimal equipment requirements during placement, thereby optimising mine resources for production. The initial paste fill design was based on the Bad Grund and Ranunelsberg Mines paste fill systems of Preussag in Germany and comprised pumping filtered tailings paste some 1.2 kin uphill from the mill to the mine portal, where cement was to be added before being distributed underground. The system was designed following initial testwork that was undertaken on a bulk sample of ore mined from the scar surface Sill Zone. Subsequently, during the mining of the Zone 96 orehody, it was found that there were significant mineralogical variations in the composition of the ore mined. Following processing, the resultant Icach residue caused significant changes in the paste rheology and therefore the pump and flow characteristics. An alternative solution was implemented that involved the use of agitator trucks to transport the cemented paste to the portal. This required modifications to the fill preparation system and also the underground distribution system. Laboratory strength tests of the HDPF using actual gold plant leach residue showed low early strengths were attained with HDPF containing only filtered leach residue. Therefore, high binder addition rates or an increase in the fill cycle time would be required to allow the fill to gain sufficient strength. A considerable amount of potentially acid generating waste rock also requires underground disposal. By blending the waste rock with the HDPF, the strengths were improved and the required cement addition rate reduced by about one-half. The potentially acid funning waste rock is encapsulated in the highly alkaline cemented paste, minimising the potential for acid generation.

Jan 1, 1998

In coal mining, geophysical techniques have an established application in determining the location of seam boundaries ahead of the face so that underground mines can be planned to avoid any geological structures that might disrupt production. Geophysics can also be used in geotechnical studies to determine the in situ properties of the rock mass and the response of the rock mass to the mining. The use of geophysical logs and microseismic monitoring in these geotechnical applications are discussed in this paper.

Jan 1, 2002

By Warren L. J, Horsley R. R, Meagher L

Mineral concentrators often use process water that is very saline and/or hard. In this paper the effect of increasing concentrations of sodium chloride and calcium chloride on the rheological properties of 70 wt% quartz suspensions (d5o - 10.6 ¦m) is reported. The apparent viscosity at 100 s t in 5 mol dm -3 sodium chloride solutions (approx. 300,000 ppm) was nearly 500 times the viscosity of water without salt or particles present. Part of the increase in viscosity is caused by aggregation (coagulation) of the suspension.

Jan 1, 1989

In late 1989, first-pass reconnaissance exploration delineated a 4km x 6km geochem- ically anomalous area centred 10km WNW of Kainantu in the Eastern Highlands Province at 6¦13'S and 145047'E. The area, named the Basangka prospect, lies between 2 200 and 2 400m asl. Interest in the area was prompted by a 14ppm Au assay of a silica-pyrite breccia float sample taken near Henkai village. The prospect was defined after several acid-leached silica- pyrite breccia and comb textured quartz float samples returned assays above lppm Au and relatively high Ag. Very encouraging and anomalous Au values were obtained from panned concentrates, despite the absence of visible Au colours. Several pan concentrates returned greater than 1mg Au and it is believed that the Au occurs as inclusions within iron oxides which were originally pyrite. In this early stage of prospect exploration, any Au value above 0.lppm in- 150# fraction stream sediments is treated as anomalous. Rock chips, panned concentrates and -150# fraction geochemistry all vividly define the areas of interest at Basangka.

Jan 1, 1991

Prefeasibility planning and cost estimation of conveyor systems has historically been undertaken by comparing fixed plant transport requirements to that of similar systems in service. This paper describes the development of a prefeasibility conveyor technical design and cost estimation application using Microsoft Excel Visual Basic for Applications (VBA) platform. The application tool known as D-Convey (Dachshund Convey) was developed with the goal enabling the end user:- to develop a technical model for conceptualised conveyor systems,- to perform economic analysis on the developed technical model, and - to conduct a comparative and risk analysis.An Excel VBA based platform was utilised to draw upon both the analytical and graphical capabilities of a spreadsheet. Some of the features of D-Convey system include a revolutionary dynamic graphical help system, known as the 'information pane' in lieu of traditional help files as well as the use of familiar graphical user interface elements such as the MS Office 2007 task ribbon. The D-Convey system incorporates material database allowing for mass handling prefeasibility estimation in other industries; it has been validated at a local quarry.

Dec 6, 2010

An experimental study of the soil mechanics of brown coal showed that brown coal consolidates in the same manner as does a clay and that the theory of consolidation for soils may be applied to brown coals. Moisture content is a function of the coal type, the existing effective stress, and the stress history of the coal.The effective stress in a brown coal seam is a function of the overburden pressure, the pore stress and tectonic stresses. Stress history may be deduced from geological evidence and determined by consolidation tests. Application of these principles to the brown coal seams of the Latrobe Valley shows that the distributions of natural moisture contents are consistent with consolidation.INTRODUCTIONThe nature and geology of the brown coals of Victoria, particularly of the Latrobe Valley, were discussed in some detail by Edwards (1945, 1948), Thomas and Baragwanath (1949) and Gloe (1960). A salient feature of these studies was the distribution of moisture contents in the brown coal seams. Recent experimental work, part of a soil mechanics study of the structure and strength of brown coal, showed that moisture content variation is a reflection of consolidation phenomena in brown coal and application of the results to .field condItions verified and modified the conclusions of Edwards in his pioneer work. Further detail of this experimental work is recorded elsewhere (Rosengren, 1961).EFFECTIVE STRESS AND CONSOLIDATIONEffective stresses in soilsA saturated soil is a two-phase system, consisting of a compressible skeleton of rigid soil particles and pores filled with water, an incompressible fluid. (In this context, the terms compressible, incompressible, and rigid are relative only and refer to orders of magnitude). If this system is subjected to stress we define...

Jan 1, 1963

By V Liebezeit

Data management is a significant, but perhaps unrecognised, consideration for any organisation embarking on a geometallurgy program. While resource geologists are accustomed to dealing with thousands or millions of samples and their associated assays, metallurgists and mineralogists have traditionally carried out only a few expensive and complicated tests and consequently tend to manage the resultant data in spreadsheets. The emerging discipline of geometallurgy arrives with significant challenges as a result of the sheer volume of data generated. As an example, the Olympic Dam geometallurgy program has generated more than:60 000 physical subsamples analysed for up to 30 analytes; 25 000 spreadsheet-based laboratory test results; 30 000 sized fractions analysed via QXRD, MLA and/or QEMSCAN;multiple external providers of data, and more than seven terabytes of data. Considerations for any geometallurgy data management system include storage space, data integrity, accessibility, traceability (sample provenance), maintenance and ease of use, integration with data providers and the ability to modify the system to adapt to changing requirements. Further, aspects of a geometallurgy program, such as conducting a range of tests on one sample, producing subsamples such as concentrates and tailings, compositing and routine QA/QC may not be well handled by existing software and providers geared to standard geochemistry, mineralogy or metallurgical test programs. The development of a geometallurgy database using existing software (AcQuire), and the associated file management system will be described for a large geometallurgy program at Olympic Dam. As with many aspects of geometallurgy there is no approach that meets the needs of every site or program. Recognition of data management as an issue, a structured approach in the program planning phase and commitment to executing the strategy will increase the chances of successfully mining the geometallurgical data.

Sep 5, 2011

By R Strand, L Reading, G Keir

A major challenge in managing coal seam gas (CSG) water is predicting how much water will be produced as the industry develops. Klohn Crippen Berger Ltd (KCB) was commissioned by the Queensland Department of Natural Resources and Mines (DNRM) to develop a tool to forecast where, when and how much CSG water will be produced in the Surat and Southern Bowen Basins under various industry expansion scenarios.The water production tool (WPT) uses the Theis equation, a non-equilibrium groundwater flow equation that accounts for the effect of pumping time on well yield in confined aquifers, to predict water production volumes. Where multiple pumping wells are in close proximity, the required pumping rates for coal seam depressurisation are reduced. Therefore, pumping effects are projected spatially to assess interference effects between wells. Water production is then upscaled to the projected scale of the CSG industry within the Surat and Southern Bowen Basins.Two modifications were made to address the dual phase nature of CSG extraction (a transmissivity reduction factor) and the impact of weathering at the eastern margin of the Surat Basin (a ænear edge effectÆ factor). These factors modify relevant hydrogeological parameters in a consistent and defensible manner to more closely match observed water production.The WPT was verified by comparing results to equivalent Theis equation calculations and to type curves provided by CSG proponents. Calibration was achieved by varying the spatial distribution and intensity of the near edge effect factor in conjunction with a chi-squared analysis of residuals.The tool, which is now being maintained and further developed by the Centre for Water in the Minerals Industry (CWiMI), was built to balance numerical complexity against relative flexibility and simulation speed. The result is a tool that can produce statistically relevant results of prescribed scenarios to plan water handling and treatment requirements in discrete zones of operation.CITATION:Strand, R, Reading, L and Keir, G, 2013. Water production simulation tool for coal seam gas operations in Bowen and Surat basins, in Proceedings Water in Mining 2013 , pp 311-320 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By L Mollison, K W. Mills, N R. P Baczynski, M F. Lee, I A. de Bruyn

This is the first of two papers concerned with rock stress inputs to various mine design issues at the large Ok Tedi open pit mine in Papua New Guinea. The companion paper (also published at this conference) is ‘The Application of Rock Stress Inputs to Stability Assessments at Ok Tedi Mine, Papua New Guinea’ (de Bruyn et al, 2014).Stresses are a required input for numerical modelling of mine design issues. However, for some operations, like the very large Ok Tedi open pit mine in remote rugged mountainous terrain, direct and representative measurement of rock stresses can be technically difficult and expensive. In such situations, development of an appropriate and sufficient understanding of rock stresses can be challenging.This was addressed for Ok Tedi by considering the following:The tectonic and regional geologic setting of the mine.Results from three different programs of rock stress measurement over 19 years, including hydraulic fracturing (1991), acoustic emission (2007) and overcoring (2010). Some interesting results of the overcoring work are discussed. It was done in a 4 km long drainage tunnel, which intersected a thick monzodiorite intrusive that has metamorphosed contacts to host contact Ieru Formation siltstones; anomalously low horizontal stresses were measured within the monzodiorite.Compilation of rock stress measurements from other New Guinea mines and prospects, both in Papua New Guinea and Indonesian West Papua.Comparisons between the variable Ok Tedi rock stresses and similar data from other porphyry copper deposits.CITATION:Lee, M F, Baczynski, N R P, Mills, K W, de Bruyn, I A and Mollison, L, 2014. Rock stresses at Ok Tedi, Papua New Guinea, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 337–346 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

FaulIing west of the Mount Isa mine is described and is shown to be related to three groups of folds that have been recognized in the area. The first period of faulting postdates the first generation folding; these faulIs are regional faults (tectonic discontinuities) which are folded by second generation folds. The faulting accompanying the second generation folding divides the area west of the Mount Isa mine into four structurally and metamorphically identifiable blocks. The most prominent of these second generation faults is the Mount Isa Fault, which is characterized by a number of distinct zones of intense second generation folding and the presence of localized layers of mylonite. Only limited evidence for brittle deformation has been observed and the major movement appears to be associated with the plastic deformation of the rocks. Confined to the areas of second generation folding in the Mount Isa Fault are numerous third generation kink folds. A detailed description of the Mount Isa and other faulIs is presented together with evidence for their existence. The displacement accompanying this faulting cannot be established because of the complexity of the structure.Postdating these faults and all the folding of the area are minor cross faults.

Jan 1, 1973

Market forces, particularly iron ore prices, demand that plant operators achieve higher throughput in the worldÆs iron ore beneficiation plants without compromising yields or efficiency. This means that production cost per ton is of paramount importance and that all major pieces of Processing Equipment have come under close scrutiny to improve throughput at their most efficient performance levels and for the longest possible continuous running time. Without doubt the use of modern engineering standards and materials of construction has contributed to matching these throughput, efficiency and availability demands. However, often not enough attention is paid to the so called æinsignificant elementsÆ connecting this metallurgical equipment, such as chutes, pipes or other conveying systems, and particularly to the sufficient protection of their wearing surfaces. The result can be an unplanned and expensive outage caused by the wear related failure of such components. This paper will discuss:the theory of wear and the multiple factors of material and design that contribute to a reduction in wear; and the combinations of modern wear resistant materials available to todayÆs engineer and how, by intelligent selection and correct application, plant availability can be optimised. Examples outlining how these principles have been applied in South Africa showing some improvements leading to increased plant availability.

Jan 1, 2002