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Reliability is not only important in coal mine planning, production and control. Reliability is also most important, and indeed is fundamental, to successful coal exporting.Coal preparation, blending, distribution, marketing and utilisation are areas of the coal industry in which reliability can be critical to coal exporting. Major elements of reliability which impact on coal exporting include coal quality, supply performance, -coal ownership changes, governmental regulations and policies, market reputations and differences in export markets.

Jan 1, 1991

By Blom W. M

Shareholders, creditors, government agencies and auditors all have a different perspective of financial reports which is determined by the uses to which they put the information disclosed in the report.Shareholders today are better informed than previously and are more aware of the market in which they are investing. This is the result of the increasing role of institutional investors and the increasing reliance being placed on analysts to interpret financial information.

Jan 1, 1990

The large El Cerrejon coal open pit in north east Columbia has been developed over the last decade in a remote, entirely new mining area with hitherto unskilled inhabitants. Now over 200 pieces of heavy equipment operate with high reliability and availability due to successful theoretical training and skill improvement programs tuned to the specific reliability needs of the worksite and environment. The process of continuous improvement adopted promises further competitive advantages of the project.

Jan 1, 1991

An attempt was made to determine the lateral extent of analcite in the Newcastle Coal Measure sediments of the Sydney Basin. From an examination of the cores of eleven bores it was concluded that the mineral is concentrated in the western sector of the original Newcastle Basin and this presumably was the region of greatest sodium concentration and aridity. The distribution of the analcite is such that it appears to have little correlative value.

Jan 1, 1967

By Gillies A. D S

The paper presents a review of research in the area of explosible coal dust with respect to safety in the underground mining environment. Research over the last several decades has concentrated on generating dust clouds in small scale laboratory explosion chambers to study flammability limits and the physical and chemical variables which affect explosion propensity. The validity of this approach is discussed and the results obtained for a range of coal types compared.

Jan 1, 1994

In conjunction with a study on wear of drag bits the effect of clearance angle on penetration rate was studied.Increases in clearance angle from 24 1/2 up to 30° gave an increase in penetration rate. Thereafter the rate was apparently affected by partial clogging with cuttings.Analysis of results was by a linear regression model and the t-test was applied to assess the significance of parameters in the penetration equation.

Jan 1, 1969

Polarization phenomena associated with the use of an agitated bed of particles as an electrode for metal deposition were studied. The concentration polarization at this type of electrode is much smaller than that occurring at a fixed or moving electrode surface. Agitated particle electrodes can be used to electro-reduce copper from solutions over a wide range of concentration and at cur·rent densities up to 2000 AIsq. ft. of bed cross section.

Jan 1, 1971

Higher commodity prices and environmental considerations will make selective narrow-vein mining more attractive in future. Unfortunately, hand-held airleg (jackleg) mining is a mature technology that has safety and productivity limitations. Despite decades of attempted innovation, no obvious successor to airleg mining has emerged. A review of some of the possible technologies is followed by a speculative description of the mine of the future, intended to stimulate thinking and discussion during the conference.

Jan 1, 2008

A new bench blast design method and its realization with the assistance of the computer is introduced. The basic design principle is to define a rhomb cell, called fully- fractured zone, through a series of full scale bench crater tests and apply this geometric pattern in multi-hole, multi- row blast design. To illustrate the design method, the optimization process and assessment of blast performance are presented in the context of a case study.

Jan 1, 1992

By Anderson DR, Tassell G

A major environmental impact study carried out in the sand dunes of eastern Cape York used image analysis of remotely sensed data to both select sites for ground investigation and categorise the different ecological units present. The approach adopted was particularly suited to the type of environment in question and allowed a high degree of quantification, at a high level of confidence, at costs several orders of magnitude less than conventional Methods.

Jan 1, 1987

By Piotto P

Pit optimisation algorithms are designed to produce a pit with maximum value, but for certain minerals like iron ore, limestone, coal, etc, it is also necessary that the designed pit contains ore which meets the customer's chemical specifications. This paper describes a technique of using linear programming for blending optimisation and the Lerchs-Grossmann algorithm (as in Whittle's 3D software) for pit optimisation in tandem, to achieve pit designs of targeted grade specifications.

Jan 1, 1996

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

The developments in hydrocyclone classification in the milling circuit at Bougainville Copper Limited are discussed. A major change in cyclone size and improve- ments in operating conditions have been made. Test work has been carried out to assess the classification performance of a modified Linatex cyclone, Wemco cyclones and a two stage cycloning circuit. The use of a scalping cyclone, to remove coarse material from the present overflow product for regrind, has also been investigated.

Jan 1, 1978

By Hagan T. N, Tucker A. J

The Cumnock Open Cut Mine (COCM) is located in the Hunter coalfield in New South Wales. Five coal seams are being mined, mostly by drilling and blasting, loaders and excavators, and trucks. The annual production of coal is 1.3 million tonnes. Overburden and interburdens consist mostly of siltstones and medium to thickly bedded sandstones. The strata dip to the south-east at approximately four degrees. There are no major faults in the rock mass.

Jan 1, 1995

Some important mineral fields are referred to in discussing the formation of placer deposits in Australia. Testing methods include boring hand, with percussion rigs; with auger and pit digging drills; and l by vibro drilling. Sampling errors are minimized by the use of correct techniques and equipment for boring, sampling, and sample dressing, A hypothetical set of data is used to demonstrate the final process of evaluation, and some relevant taxation provisions are discussed.

Jan 1, 1964

By Mackinnon I. D R, Glikson M

Samples from the Callide Coal Measures, Queensland, Australia, containing the minor maceral, micrinite, have been studied using optical and electron-optical techniques to determine the precise compositional and structural nature of micrinite when in association with vitrinite macerals. Emphasis has been placed on direct spatial correlation of optical and electron-optical data due to the fine grain size (90 per cent of the component) and, as such, should not be considered a maceral.

Jan 1, 1991

Sublevel open stoping was introduced at Rosebery in 1972; most of the stoping prior to this was horizontal cut and fill. Sublevel open stoping presently accounts for 65% of the Rosebery underground production of 560 000 tonnes per year. This primary stoping technique leaves 50% of the ore in the crown and transverse pillars. The methods used in pillar recovery to date are reviewed and comments made on the success of these operations.

Jan 1, 1982

By S Carr-Cornish, K Moffat

Social licence to operate is developed and kept through managing both operational impacts and the relationship between local community and company. However, CSIRO research has demonstrated that in determining how accepting community members are of a mining operation, relational factors, such as procedural fairness and trust, are much more important than operational impacts, such as impacts on employment and the environment (Moffat and Zhang, 2015). Companies seek to develop relational factors through their engagement with local community; such engagement has many aspects, including, initially identifying stakeholders and positioning the company as part of the local community (Lacey et al, in prep; Thomson and Boutlier, 2011). These relational factors involve the social identities of people living in the community. Social identities are a part of people that shape their beliefs, based on their connections with various groups in their lives (Hogg et al, 2004).An engagement process, intentionally or not, inevitably interacts with the social identities of stakeholders (Crane and Ruebottom, 2011). For example, traditionally, at the very beginning of engagement processes, community members are assigned to categories using conventional stakeholder mapping and categorisation methods, often based on assumptions about stakeholders’ interests, which equates to assumptions about stakeholders’ social identities (Colvin, Witt and Lacey, 2016; International Council on Mining and Metals, 2012). Yet, there has been limited empirical inquiry into whether such categories reflect the social identities of stakeholders and if there is a bearing on relational factors, including, the perceived fairness of consultations and trust in mining companies (Crane and Ruebottom, 2011). Also at this time, companies commonly seek to create a presence in communities, for example, joining Chambers of Commerce and participating alongside community members. Again, there has been limited empirical inquiry into whether community members and companies identifying with the same overarching group and thus sharing aspects of social identity, influences relational factors (Crane and Ruebottom, 2011). In this study, we examined the effects of changing aspects of social identity by changing how stakeholders were identified and companies were positioned, on how stakeholders’ perceived a new mining operation, specifically how they perceived the procedural fairness of the proposed consultation process and trusted the company, two factors that underlie a company’s social licence to operate.CITATION:Carr-Cornish, S and Moffat, K, 2016. Out of the box – the power of social identities in engagement processes, in Proceedings Life-of-Mine 2016 Conference, pp 180–182 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By D Lau

Traditionally X-ray diffraction (XRD) has not been significantly used by the cultural heritage sector, as the most commonly used technique, X-ray powder diffraction (XRPD), requires sample removal from the artwork or artefact, followed by grinding of the sample to a fine powder. With the development of micro-X-ray diffraction (micro-XRD) and other associated advances, non-destructive, in situ analysis of crystalline pigments on micro-areas of paintings and artefacts has become possible. This is illustrated with the application of this technique to the in situ analysis of propriety paints, paint cross-sections and small paintings. However, workers have noted that XRD can be insufficiently sensitive with pigment mixtures, due to matrix effects. This study obtained X-ray diffractograms of 17 single pigment preparations and determined relative amounts of crystalline content. The purity of single pigments was compared with Joint Committee on Powder Diffraction Standards (JCPDS) database diffractograms. The impact of pigments with high X-ray absorption coefficients on the detection limits of pigments with low X-ray absorption coefficients was further investigated by building on work done with the chromium oxide-zinc oxide series with the preparation of a second series of binary mixtures of zinc oxide (which has a high absorption coefficient and is almost fully crystalline) and ultramarine blue, which has a lower absorption coefficient but which is more crystalline. Semi-quantitative analysis, where baseline and absorption factor corrections are made, confirm detection limits as low as five per cent for chromium oxide and ultramarine blue when in a binary matrix with zinc oxide. However, this type of analysis is very time consuming. So in order to theoretically simulate issues that will be encountered with binary pigment mixtures, the single phase diffractograms were used to theoretically investigate the matrix effects of the three white pigments with the various coloured pigments. This illustrated that detection limits can be as low as five per cent or in non-ideal conditions, such as with partial peak clashes or where there are large differences in relative peak intensity, as high as 50 per cent. These results have significant implications for the analysis of painted surfaces on artworks or artefacts. It has been demonstrated that ideally this method is more suited to the investigation of surfaces where there is minimal mixing of pigments or where there is not a significant difference between the absorption coefficients of the mixed pigments.

Jan 1, 2008

By C J. Ptacek, J G. Bain, D W. Blowes

The passive interception and in situ treatment of groundwater using permeable reactive barriers (PRBs) has, within the past decade, become an accepted remedial approach to the control of plumes containing dissolved organic and inorganic contaminants. Since the first applications of the technology in the early-1990s, there have been several field-scale PRBs that have provided excellent treatment of dissolved metals in groundwater. Additional commercial applications and demonstration projects continue to be developed. Three field-scale applications and supporting laboratory columns have shown that several thousands of milligrams per litre of sulfate, more than 1000 mg/L iron, and several tens of milligrams per litre of other metals can be removed from groundwater by PRBs that promote sulfate reduction. The reactive materials, which incorporate various forms of organic carbon, promote microbially mediated sulfate reduction, the generation of hydrogen sulfide, and the subsequent precipitation of sparingly soluble iron and other metal sulfide minerals. Effective performance has been achieved by PRBs installed at a mine-tailings impoundment in 1995 (Sudbury, Ontario) and at an industrial facility (Vancouver, British Columbia). These PRBs have removed iron and other metals from groundwater. Similar materials were also used to create reactive layers within test cells directly in a tailings impoundment in 1999 (Timmins, Ontario) with the objective of removing iron and sulfate from the pore water before it migrates from the tailings impoundment. Zero-valent iron (ZVI) has been shown to provide excellent removal of chromium (VI) in a PRB, which was installed at the US Coast Guard facility in Elizabeth City in 1996, by reduction and precipitation reactions. Laboratory tests have also shown that ZVI reduces As(V) to As(III), which is subsequently removed from solution by co-precipitation with iron oxyhydroxides. In groundwater containing sulfate, ZVI and mixtures containing organic carbon can promote sulfate reduction and the subsequent precipitation of sparingly soluble arsenic and other metal sulfides. A trial PRB system was installed in 2001 and was shown to attenuate arsenic and other electroactive metals in groundwater at an industrial facility in northwestern Ontario. Basic oxygen furnace (BOF) slag, a waste material generated by the steel industry, has shown excellent potential for the removal of phosphate, elements such as arsenic and water-borne pathogens from groundwater in field and laboratory tests.

Jan 1, 2003