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By D Johansson, C Yi, U Nyberg

Emulsion explosives are a common industrial explosive and have a non-ideal detonation behaviour. The detonation performance for a given product changes with the charge diameter, ground conditions, con?nement and density. The burning process of an emulsion explosive has been modelled with an ignition and growth model in the LS-DYNA code. The parameters in the burning rate function are calibrated by the detonation velocities and the detonation front curvature radii from emulsion explosive tests. A Perl program was developed for an efficient estimation of the parameters, and the results show that the calibrated parameters can predict both detonation velocities and the detonation front curvatures.CITATION:Yi, C, Nyberg, U and Johansson, D, 2015. Parameter determination of an ignition and growth model from emulsion explosive tests, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 585–590 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By MattelmSki M

Outokumpu Harjavalta Metals Oy has been producing nickel since 1962, based on conventional flash smelting technology followed by electrowinning of nickel. In the 1980s, a research project was initiated to develop a converterless direct smelting process to produce matte for further refining in the then existing refinery. The process was tested on a pilot plant scale at Outokumpu's research centre in Pori and was found to be viable. The process was named the Direct Outokumpu Nickel Smelting Process or the DON Process. At the turn of the 1990s, Outokumpu studied various options to develop its nickel business and the Harjavalta operations. As a result of this work, the DON Process was further developed to produce two mattes: low iron matte in the flash furnace to be leached in the existing leaching circuit and high iron matte in the electric furnace to be leached in the new leaching circuit. In Harjavalta's case, it was essential and important that the process could use the existing flash furnace and electric furnace without converters.

Jan 1, 1996

By S Thomas, E Grimsey

Mining education in Australia has undergone another cyclical downturn over the past five years and several departments have been discontinued while others are still teetering on the brink of destruction. During this downturn Curtin UniversityÆs WA School of Mines (WASM) has managed to stay alive and well, but this has not been by accident. This paper outlines some of the strategies and experiences that have kept WASM in a strong position and offers hope to other departments and schools elsewhere that are still experiencing difficulty. This paper is also directed at all mining departments and schools that are certainly going to see it all happen again after the next mining boom turns to bust.

Jan 1, 2004

By S Van Duin, I Porter

This paper discusses how advanced manufacturing technology (AMT), which is fundamentally reliant on and developed via multi-disciplinary skills, has benefitted non-mining industries, and what lessons can be derived from this experience to benefit the mining industry, particularly underground coal mining. Examples of AMT use in æconventionalÆ industry, some drawn from the more than 25 years experience in many different industries of the Automation and Robotics team at the University of Wollongong, are described to show typical benefits, risks and opportunities expected in using AMT. Applying AMT to mining brings many unique challenges and this paper expands on these and then provides practical examples of how a multi-disciplinary team can develop new processes and systems leading to productivity, safety and other benefits for underground coal mining.

Sep 26, 2011

By B A. Wake, G G. Lowder, M J. White

The Tooloom gold field is located within the New England Fold Belt in the far northeast of New South Wales, approximately 130 km south southwest of Brisbane. Gold was first discovered at Tooloom in 1857. Within a few years up to 10 000 people were mining placer gold deposits in the Tooloom valley and a few tried their hand at mining hard rock occurrences as well. Mining of alluvial gold continued in a small way at Tooloom until very recently, but only in the last few years, since Malachite Resources acquired its interest at Tooloom (now 100 per cent), has the full potential of this large, reduced intrusion-related gold field been appreciated. By the mid 1870s, once the alluvials were largely worked out, most of the early miners had made the 270 km trek north to the newly discovered Gympie gold field and Tooloom slipped into obscurity. Such was this obscurity that the Tooloom gold field was not recorded on published Government geological maps until 2001, four years after Malachite became involved. The many hard rock prospects that Malachite has identified in recent years were largely or completely unknown. Tooloom is a good example of blinkered thinking when it comes to modern mineral exploration. The New England province in NSW has long been the æpoor relationÆ to the much better known and more highly favoured Lachlan Fold Belt in NSW. It has also suffered serious neglect compared with the Queensland part of the New England Fold Belt that hosts such major gold deposits as Mt Morgan (>7 Moz), Gympie (>3 Moz) and Cracow (>1 Moz). Tooloom is proof that prospective geology does not stop at state borders.

Jan 1, 2004

By K A Plumb

New structural studies in the Walker Fault Zone of eastern Arnhem Land are integrated with basin-wide reconnaissance observations, made to refine models for the structural evolution of the McArthur Basin and provide new insights into the nature of metal logenetical ly important pre-inversion phases of the basin's evolution. At least five principal events may be identified during the Proterozoic: The Tawallah Group and equivalents were deposited throughout the McArthur Basin during an extensional event. Rifting of an incipient Batten Trough occurred at this time, in a terrain characterised by orthogonal, linked extensional faults. Uplift and erosion of the Tawallah Group accompanied continuing extension and was penecontemporaneous with continuing deposition of the overlying Parsons Range Group, within a precursor to the Walker Trough. Dt (of the Walker Fault Zone) relates to a new rifting event, penecontemporaneous with deposition of the McArthur Group and its equivalents in the Walker and Batten Troughs. This rifting accompanied dextral strike-slip faulting along northerly-trending bounding faults, as a result of northwesterly-directed oblique extension, leading to pull-apart basins. D2 inversion of the Batten and Walker Fault Zones pre-dates deposition of the Roper Group. In the proposed model WNW-ESE directed shortening (D2.), accompanied by folding and thrusting, and by local development of cleavage in the Walker Fault Zone, is seen to be followed by northerly-trending sinistral faulting (D2b), about a SE to ESE-directed compression. D3 is basin-wide and post-dates the Roper Group. It is characterised by conjugate faulting and folding about ENE to NE-directed compression. The latest Proterozoic event to be identified (D4) comprises widespread north-trending strike-slip dextral faulting of Roper Group, coupled with N-S directed thrusting across the Urapunga Fault Zone and Murphy Inlier This is accompanied by late dextral reactivation of NNW to NNE-trending faults in the Walker and Batten Fault Zones.

Jan 1, 1994

By Golledge P

Access to the vast volume of exploration data available in the Geological Survey Division of the Department of Mines would be impossible without the use of modern computing methods. These data are used by geologists in the early stages of exploration activity and methods of access to those data by the mining public are discussed. A regime of the Department's current hardware and applications software usage and possible future developments to enable more efficient processing of administrative matters and the production of maps using on-line graphics are included.

Jan 1, 1983

By Miller B

General experience with improvement programs in the mining industry has been that, after some initial success, performance tends to deteriorate back to pre-improvement program level in a relatively short time after the spotlight is switched off.

Jan 1, 1998

By Ryan CG, Cousens DR, Suter GF, Griffin WL

A novel method utilizing PIXE with microbeams following fire-assay has been developed to determine PGE and Au at sub-ppm levels suitable for application in exploration. Analyses of the prills from the lead and silver fire-assay yield Pt, Pd and Au concentrations readily. NiS must be used as collector if the complete suite of PGE is required, but this method is not as Convenient.

Jan 1, 1989

By Warren R. P

When the original Mount Gunson joint venture, between CSR and United Uranium ceased operations in December 1971, an intensive ex- ploration campaign was launched to prospect for more ore in the Mount Gunson region. This campaign resulted in the discovery of the Cattle Grid deposit. A comprehensive sampling programme proved the existence of 4.6 million tonnes of ore, at a mean grade of 2.4% Cu, calculated at a 1.0% Cu cut-off. The planning and development programme that followed this discovery included not only the mining and metallurgical aspects of the exploration of the deposit, but also the en- vironmental aspects. Preliminary work included data collection with respect to meteorology, soil types, and existing flora and fauna.

Jan 1, 1976

The cost of constantly extending a decline tunnel that plays a part in the actual extractive process is a revenue cost. The characteristics of such a decline tunnel are that it is dug in a series of relatively small excavations. It follows the ore body and is dug as close to the ore body as practicable. In addition, the decline allows for the extraction of ore in the immediate vicinity, with the ore being extracted in a relatively short period of time.

Jan 1, 1990

Australasian mining companies expect a high standard of professionalism from their metals exploration teams. They also have, increasingly, a global perspective, employing explorationists of diverse cultural backgrounds and operating in diverse environments. Human resource development (HRD) of these professional explorationists needs to address all personal facets of functioning independently and interdependently in a modem working culture, as well as the needed technical competency. Creation of a learning organisation to promote this development is critical. Organisational consultants can support managers and supervisors as mentors facing the wide spectrum of development required by the explorationists; mentorship and guidance counselling can then complement training in the maturing of professionals from technical competence to professional independence and interdependence. Empowerment and clearly stated expectations are keys by which professionals can learn efficiently and effectively.

Jan 1, 1996

Conceptually coal reserve assessment is simple but in practice it presents many problems. These arise from the origin and geological history of coal seams and from the diverse nature of the coal itself. The suitability of a coal for a particular use depends upon its type and so sheer quantity of reserves does not guarantee the adequacy of coal reserves for all requirements. Codes have been formulated to counteract the effects of subjectivity in reserve assessment. The code for calculating and reporting coal reserves published by the Standing Committee on Coalfield Geology of New South Wales has wide acceptance but the Committee itself recognises that it has shortcomings. Currently the Committee is engaged on the commendable but difficult endeavour of formulating a code that will meet the needs of scientific rigour and professional and commercial ethics and that will allow the specification of an assessment method without constraining it. It is generally agreed in the coal industry that the assessment of coal reserves can not conveniently be incorporated into codes formulated for other resources.

Jan 1, 1979

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 Silitonga M

Generally, the acceptable parameter for predicting the intensity of ground vibration due to a blast is the amount of explo ive u ed and the distance from the explo ion. A eries of closely controlled tests were carried out and it was observed that the degree of confinement or burden of an explosive charge play an important role in the variation of the transmitted magnitude of the shock wave through the ground.The intensity of the shock wave increases with burial depth or with greater confinement of an explosion until a critical depth is reached.Beyond this critical depth, the magnitude of ground vibration remain constant. This is an important finding, which explains the anomalies between the expected level and the monitored ground vibration in a particular situation.

Jan 1, 1984

By Budd B

this paper outlines the operating advantages gained through applying a mine processor (MISA), to various underground and surface operations. On the surface, MISA monitors and/or controls ventilation fans, crushers, fill plant and stockpiles. Underground, MISA monitors and/or controls dewatering pumps, fill reticulation and high voltage electrical distribution on most levels.

Jan 1, 1988

Operations at two open cut mines have so far commenced on two out of the five potentially mineable seams in the Fair Hill - German Creek Coal Measures. Due to seam splitting, up to seven mining units are present in the Dysart Seam interval at Peak Downs giving a total of 12 mining units in the section. The coal is low to medium volatile type and produces strong coke. Rank increases and fluidity decreases in the southern part of the area.

Jan 1, 1974

By Lama RD

The paper outlines the development in the control of dust in Australia over the last 20 years. Factors influencing dust make at the faces are discussed. The effect of high production systems is analysed. Changes in dust standards and results of dust sampling on longwalls and continuous miner panels are given. Research conducted on air curtains and water infusion on dust control on longwall faces is presented along with recommendations for future research. It is found that both dust curtains and water infusion can cut dust mak by 50" each when applied separately.

Jan 1, 1988

Ore petrology will fundamentally determine the types of metallurgical processes employed for ore treatment, their operational efficiency and the nature of processing problems encountered. It is therefore paramount that the petrological charact

Jan 1, 1998

By S Corbel, P J. T Donchak, W Gorczyk

The Hodgkinson Province numerical modelling project aims to develop an improved understanding of the physical conditions that lead to the localisation of goldbearing fluids within known systems and apply this understanding to the prediction of potential new sites of gold mineralisation. The project follows a series of stages from identifying the key parameters required to construct and test simulations through to reverse engineering of known deposits and ultimately applying the conditions identified in the preliminary stages to predictive simulations. Results of the modelling demonstrate strong geometric controls of the localisation of fluids during mineralisation. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008