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Some fundamental aspects of recent single-particle fracture studies are reviewed. Findings from this research shed new light on the utilisation of energy during comminution operations and provide useful pointers to new research directions that could lead to significantly better comminution machines. Two methods for quantitatively predicting mineral liberation during comminution are reviewed. These methods have been developed into useful practical procedures, but they are almost unknown in the mineral processing community. Their use should promote the consideration of mineral liberation as an important variable to be considered during the design and operating control of comminution circuits.

Jan 1, 1993

The majority of coke in Australia is made in by-product slot ovens at steelworks in Port Kembla, Newcastle and Whyalla. Most of the coals for these plants come from New South Wales but a regular proportion of Queensland coals may be introduced. The plants and the coals are reviewed in the paper.

Jan 1, 1975

When preparing an appraisal, valuation or feasibility study for a new mining project it is difficult to imagine the technical, economic, social and environmental context that the project will occupy in ten or 15 years time. This paper is about our ability to foresee the future, the choices available now in matching the project to that future context, and about the flexibility that exists in adapting the project to a changing environment. The author draws upon his experience of project reviews, valuations and feasibility studies in the mid to late 1980s in Australia and New Zealand to explore how the project context has changed since key decisions were made and what this tells us about decisions made today for future projects.

Jan 1, 2004

AustraliaÆs current interest in renewable energy is based on a desire to reduce the countryÆs greenhouse gas emissions. Wood from sustainable sources offers a unique opportunity to combine greenhouse gas benefits with other significant environmental and social benefits, including salinity mitigation, carbon sequestration, soil replenishment and rural industry. The challenge is to make renewable energy from wood in a cost competitive manner, so that this broad range of benefits may be best realised. Bioenergy and carbon products are of great interest as new, commercial forestry products that can drive large-scale environmental tree planting:In Western Australia, Enecon has worked with Western Power Corporation to build the first full-scale plant for integrated processing of mallee eucalypts, to produce activated carbon, renewable power and eucalyptus oil. It is intended that this plant is the first of a number of such plants to help catalyse environmental tree planting in Western Australia. New technologies being developed overseas may provide competitive bioenergy in areas where traditional markets for wood do not exist. For example, pyrolysis converts wood into a bio-oil that may be transported to remote sites for power generation in gas turbines. Pyrolysis also produces wood char. Pyrolysis and wood-to-ethanol technologies, coupled with short rotation coppicing trees, offer the long-term prospect of large-scale production of renewable fuels around the country.

Jan 1, 2006

Through partnering with mining customers, DYNO has been able to develop some specific technologies that benefit blasting operations particularly in underground mining. Some of these areas are: 1. Cost allocation and product tracking systems; 2. Borehole video surveys of breakthrough blastholes; 3. Borehole video photography for logging VRM blastholes; 4. Toe-load uphole loading for sublevel cave mining operations; 5. 3D blast modelling for underground ring blasting. This paper outlines these developments in the context of a Canadian underground metalliferous mine.

Jan 1, 1995

After the last world war, management tended to change from an acquired skill more associated with experience than formal training, to a specific widely-recognised specialism requiring an involved formal education process.That process, of necessity, required the development of business schools, M.B.A. courses -indeed the setting up of professional chairs to deal with the intricacy of general management development.Management research burst forth bringing forward new and exciting theories which developed new techniques, tools and terms.

Jan 1, 1985

A report is given of the problems of finance and physical resources that currently affect The University of New South Wales, and of some of the measures adopted to alleviate them. Partly as' a result of review procedures, a School of Mines was formed to amalgamate Applied Geology and Mining Engineering, and to add the skills of extractive metallurgy to produce a group to match the needs of the minerals industry. A review of courses within the School indicated a need for enhanced computer teaching, which is partially negated by a lack of resources. It also shows an overcrowded course whose structure could possibly benefit from a split into managerial and specialist streams.

Jan 1, 1986

In the mining and minerals industry, development, introduction and construction of new plant designs, to meet sustainability objectives, face a series of major hurdles. Typical are the long investment cycle times, the designer does not normally control the spending (the owner does), and the industry is inherently technologically conservative or risk adverse while accepting the often more significant geological, market and political risks.æSustainable Plant DesignÆ is an approach to plant and facility design that drives the necessary culture change and acceptance by minimising technical risk and maximising potential returns. The approach forces consideration of sustainability objectives and risks early in the project, where cost saving and efficiency improving opportunities can be maximised.In Hatch, we are using three proven tools under the ærisk managementÆ umbrella to drive sustainable development principles into our projects:Sustainable Plant Design, FutureWatchTM Reviews, and Clean Plant DesignTM . These proactive practical, not theoretical, techniques for driving change from within and reducing whole of life cycle costs will be discussed and illustrated with case studies.

Jan 1, 2004

By Kubik K

This paper reviews the historical data on relative height changes of landmasses with respect to sea level for Pacific Rim countries.It discusses existing theories of the Greenhouse effect, and the interaction with the vertical movements of the continental plates which leads to different effects for different places. Possible future scenarios are described and directions for future research and measurement programs are given.Relative sea levels are governed not only the increase of water from deglaciation but also by a range of other factors such as variable water storage in lakes and the atmosphere, thermal expansion of the ocean, ocean currents, and the shape of the ocean and the continents. Sea floor spreading, for example, is ultimately more significant than deglaciation in sea level control but is generally much slower.

Jan 1, 1990

By D Lawie

Prior to resource modelling, sample scale data is normally grouped into spatial domains that reflect zones of homogenous properties. These domains are usually based on a combination of grade and other variables that reflect, for example, geology and alteration, or variables known to correlate with properties of the samples that affect downstream processing. Domaining and wire-framing sample scale data is a time intensive task and it is difficult to track more than a few variables simultaneously while establishing domain boundaries. This is especially the case in operations with complex data, for example, a combination of multi-element assaying of total element concentrations, and/or phase specific assaying such as sulfide sulfur, carbonate carbon, cyanide available gold, and/or downhole geophysical measurements. To minimise unintentionally grouping samples of contrasting properties within the same domain, unsupervised statistical methods are available that can automatically identify samples atypical of the domain, both as univariate tests, and as tests that take correlation within the domain into account. Unsupervised methods in this context means methods of identifying atypical samples that require just the selection of the domain and input variables. Thresholds are derived robustly from the data itself, and the results are therefore repeatable and operator independent. Atypical samples may be thought of as outliers, ie, samples that are separated from the ‘majority’ of the data. If these atypical samples are themselves spatially associated, they may be allocated to an alternative existing domain or allocated to a new domain. Care should always be taken to ensure that identified outliers are due to meaningful causes and not due to data coding and storage errors, although the identification of the latter is still valuable. *This is an abstract only. No paper was prepared for this abstract.*

Sep 5, 2011

By Johnston G, Joyce C

The permitting of new mining projects has evolved into a highly complex process that must be carefully managed. Only by developing a thorough understanding of the issues involved and stakeholder interrelationships can successful strategies be developed that integrate the often competing demands of: ò regulatory requirements, ò commercial requirements, ò social/cultural needs, and ò technical issues. Properly implemented, this approach can result in: ò shortened approval timeframes, ò better project definition ò broad based community support, and ò favorably disposed government departments.

Jan 1, 1997

There are many types of environmental audit: compliance, impact, risk and management audits; internal and external audits; single and multiple-project audits. All are becoming increasingly important in corporate management as new legislation confers increasing personal liability on directors, executives and staff of corporations and agencies in both private and public sectors.

Jan 1, 1990

In an industry that is data-hungry and increasingly international in its outlook, the role of the New Zealand Government in facilitating exploration and mining activity here presents unique challenges. All things being equal, the Regime itself should result in æefficient outcomesÆ, however central to this rational economic tenet are the assumptions that the regime is in keeping with the times, other legislation works in tandem with it, and that those who administer the regime have the knowledge and experience to apply the rules wisely. Following the Crown Minerals review in late 2003, a shift in emphasis from Crown Minerals æmanaging the ActÆ towards proactively æmanaging the mineral estateÆ for greater benefit for all New Zealanders means that these assumptions are being increasingly challenged and addressed through a variety of initiatives. These include improved access to relevant data sets, minimisation of red tape and compliance costs, increasing emphasis on permit holder compliance with work programme obligations, changes to the Minerals Programme and regulations, closer collaboration with and representation to other government departments and councils, and additional recruitment of industry-experienced staff. This presentation will highlight aspects of these initiatives, and examine how they will collectively contribute to facilitating future exploration and mining activity in New Zealand.

Jan 1, 2004

By Hart J. G, Anderson J. S

The presence of platinum metals in the nickeliferous copper ore of the Thomson River Copper Mine near Walhalla, Victoria, was first revealed in 1905 by assays made in the laboratory of the Department of Mines (1).These disclosed the presence in the ore of 5 dwt. platinum metals, 1 dwt. gold and 13 dwt. silver per ton. Attempts to isolate the platinum-bearing mineral were unsuccessful, and the absence of obvious native platinum led the assayer, Mr. P. G. W. Bayley, to suspect that the platinum might be present as sperrylite. Subsequently, Mr. C. M. Lyons, then metallurgist to the Long Tunnel Gold Mining Company, Walhalla, tried to isolate the platinum mineral from samples of ore containing as much as 7 dwt. platinum metals, but again without success.In 1912, a sample of copper matte from this ore was submitted to Messrs. Johnson, Matthey and Company, Limited of London, for analysis. The analysis, which is quoted below by their courtesy, revealed tnat a large proportion of the metal pi'eviously reported as platinum was palladium, there being about two parts of palladium in the matte to one part of platinum.

Jan 1, 1942

Contract mining is an integral part of the underground and surface hard rock mining industry in all states of Australia. Contract mining is now makes a major contribution to the opencui coal industry in Queensland and New South Wales with Thiess alone producing over 16 million tonnes per annum with safety performances that most coal companies would be proud of. Contract mining is now attracting interest in the underground coal sector.

Jan 1, 1998

By C J. McKenzie, D F. S Natusch

The lignite deposits of Southland and Central Otago are a potentially significant energy resource for New Zealand. Current estimates put the technically mineable lignite reserves at 5.3 billion tonnes, which is more than ten times the energy content of the Maui gas field. Thus, the strategic importance of the lignite as a basis for maintaining current levels of self-sufficiency in transport fuels, or as a possible feedstock for electricity generation, deserves full investigation. The full extent of the lignite deposits was only recently established as the result of a scout drilling programme undertaken between 1976 and 1979 by the Mines Division of the Ministry of Energy, and from companion studies conducted by the New Zealand Geological Survey. These discoveries of large quantities of lignite coupled, at the time, with rising oil prices, raised the prospect of their development for production of transport fuels.

Jan 1, 1983

By X Y. Ma, X G. Tian, P F. Zhang, T B. Zhao, Z H. Li, Z Y. Fu

This study analysed the fracture characteristics and movement process of goaf roofs under the condition of gangue backfilled mining, based on the engineering conditions of Tangshan Mine F5001 gangue backfilled working face. The inclined borehole detection method is adopted to conduct long-term and fixed-point detection of the roof stability. The distribution characteristics of mining-induced cracks in the roof are described quantitatively based on the crack density, and a similar model test method is used to assist the analysis of the roof movement under the control of gangue backfilled mining using stress sensors and digital speckle deformation field monitoring. The results show that under the condition of gangue backfilled mining, structural cracks in the roof typically appear at the boundary of rock strata. The appearance of cracks is related to the rock strata where they are located. Structural cracks appear in the form of single cracks ahead of the working face and develop into structural cracks in the goaf. The roof movement of the coal seam develops in five stages: fracture incubation, crack extension in advance, dense fracture development, steady fracture expansion, and roof stability. Separation forms the primary component of the roof subsidence, accounting for more than half of the subsidence value. The separation generally extends over a long distance along the strike, and vertical crack-intensive areas appear in the roof above the cut-off and stop line. The findings of this study provide a theoretical basis to support designs of backfilled mining and upgrading of hydraulic supports in working faces.

Nov 29, 2022

By A Robertson

Australia has been slow in adopting the use of underground space as a part of our urban planning process. Australia has one of the highest levels of tunnel advance per capita per annum in the world, yet the use of underground space in our cities appears difficult for our planners and politicians to comprehend, not withstanding the general availability of good quality rock and contractor expertise in Australia. However, the lack of space in our urban areas is being highlighted as our major cities expand outwards and people and businesses gravitate towards city centres. Typical potential underground space uses include car parking, self-storage and archiving facilities, water storage, underground quarrying, small industrial facilities and another layer of traffic (electric and fuel cell) and services network. Historically, blasting in high density population areas has resulted in blast vibrations and blast overpressures exceeding the limits, which in some case have been set extremely low in terms of peak particle velocity (PPV). This makes conventional blasting difficult, often requiring low charge weights per delay and associated small blast sizes and slow advance rates. However, the introduction of new technologies, such as computer aided drilling, electronic delays and low-energy explosives has made this task considerably easier. Although more expensive than conventional blasting, excavation by blasting using these products and technologies in relatively good quality ground is believed, in most cases, to be less than the cost of mechanical excavation. In this paper, the authors look at innovative trends in underground quarrying, underground commercial space and tunnelling and put forward their concept of future excavation demand, future product requirements and technical specifications to the drill and blast community.

Jan 1, 2007

In the current climate, there is a real need to bridge the gap between theory and the real world mining considerations, and develop viable, cost-effective, high performance thickeners. With a greater need to extract profits from both difficult-to-process ores and lower grade orebodies, coupled with the necessity to produce 'greener', less water intensive technologies, suppliers need to take current thickener designs to the next level and into the 21st century. The complexity of 'getting it right' within a thickenerÆs feedwell, the 'nerve centre' of the thickener, is no small task. Delivering dilution water and mixing this water with incoming feed slurry, addition of flocculant, maximising flocculant-slurry interaction to build aggregate size, minimising unabsorbed flocculant percentage, volume average of solids volume fraction, momentum dissipation ratio, dilution recycle ratio, volume average shear, maximum shear rate at exit, aggregate size on exit, uniform discharge profile and more ù all of these need to occur in the right order and in the right proportions within the feedwell. This paper discusses the genesis and evolution of a new feedwell design, the first major innovation in the thickening industry in over 15 years.

Jan 1, 2008

Australia has a long and successful record in mineral processing technology extending over 100 years. This has included the development of new processes and equipment and new analytical techniques. These developments have added greatly to the efficiency of mineral processing and thereby to Australia's national wealth. Demands on mineral processing engineers in the future show no signs of diminishing, in fact they will increase considerably as more difficult areas must be treated and the requirements for quality control become more stringent. These demands must be met successfully since mineral processing must continue to be one of the most important technologies in Australia's economic future.

Jan 1, 1989