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By Chappell BW

A zone of northwest trending dykes extends for over 600 km in the hinterland from Cairns to Mackay. In sate regions the zone is up to 120 km wide. Figure 1 shows their approximate extent, compiled from published regional maps and from specific studies in more limited areas : Palm Islands, Cardwell Ranges, Jourama Falls, Townsville area and Burdekin Delta. The context of the dyke swarm is the Tasman Orogenic Zone, the region of Eastern Australia conprised of Palaeozoic metamorphic, sedimentary, volcanic and plutonic rocks which has experienced a complex history and evolution. In the Whitsunday region, the Tam-an Zone also involves Cretaceous volcanism and plutonism. Geological relationships indicated a wide span of ages for the intrusions in the dyke, swarm zone. They intrude a range of volcanic and sedimentary rocks, and in some areas plutonic rocks. Older dykes, apparently part of the same regional swarm are intruded by sate of the granites.

Jan 1, 1987

By R W. Wilson, A R. Branch, T S. Pooe

The original bulk air cooling system at this particular mine made use of two water chilling refrigeration machines to produce peak cooling of approximately 12 MWR with a downcast air temperature of about 7°C; however, as the shaft is not used for transporting personnel, the opportunity existed to supply more cooling to the mine by lowering the downcast air temperature. An ice storage facility has been constructed and provides a range of opportunities in operating the system: colder air temperature sent to the shaft, enabled by using near-zero degree water produced by melting ice to cool the air; electricity time-of-use management, by shifting electricity usage out of peak tariff periods; and increased peak cooling capacity, by melting ice while chilling water. Ice is created in the storage facility at night while the ambient air temperature is low and then melted to produce cold water when required by the cooling process. An ice dam was constructed and serpentine stainless steel coils installed where the ice is produced; one of the refrigeration machines was converted to chill a glycol solution to subzero temperatures to create the ice on the coils; a plate heat exchanger was installed to allow the glycol chiller to act as a water chiller as well; and a third spray stage was added to the bulk air cooler to utilise the near-zero water. This paper describes the thermodynamic design, construction and performance assessment of the new system, which is unique, novel and represents the state-of-the-art of this type of cooling system and energy management.CITATION:Branch, A R, Wilson, R W and Pooe, T S, 2015. Novel use of ice thermal storage for energy management on a mine refrigeration plant, in Proceedings The Australian Mine Ventilation Conference, pp 185–192 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By S Totsuka, P Ortiz, E Prokkola

Electrochemical polarisation techniques can be successively applied to maintain clean surfaces in process environments. The applications are the result of extensive knowledge of the electrochemical nature of process environments, an innovative approach to problem solving and shared æcan doÆ attitudes between the supplier and process owner. Initial identification of suitable applications is based on over 20 years of process and electrochemical experience. The technologies discussed in this paper include Electrochemical Anti-Scaling [EAS], Electrochemical Protection Systems with both anodic [EPSA] and cathodic [EPSC] protection and Electrochemical Flocculation [EF]. Examples of industrial applications are reviewed. Good examples of metallurgical processes which can benefit greatly from an advanced electrochemical treatment are the wet processes involving precipitation, crystallisation and evaporation. Eliminating corrosion and scaling which would otherwise cause process disruptions and quality problems can make a big difference in process profitability. Clear advantages in both cost efficiency and environment friendliness are easily demonstrated. Continuous processing with minimum downtime is one clear advantage. In comparison to the use of corrosion inhibitors, anti-scaling agents and flocculants, the electrochemical polarisation does not increase the environmental load from the process as no additives of any kind are used. In most cases the cost benefits from pro-actively keeping surfaces clean with the help of advanced electrochemistry are substantial when compared to traditional re-active methods and other active treatments.

Jan 1, 2004

In recent years there have been a number of excellent towns built for mining communities in remote parts of Australia. Planning has been thorough, and very large capital expenditures have been made by companies to provide high standards of accommodation, services and amenities. But so often the phrase 'company town' comes to be applied, expressing the frustrations of the residents, working for a single employer who dominates their lives, and of the company, which would prefer not to have to build and operate a town. The much-vaunted early success of some iron ore, bauxite and coal projects has led to a belief that the success of all mining projects is assured. Those holding this belief ignore the vagaries of mineral deposits and of markets, and the need to amortise large high-risk capital expenditures, much of which is spent on social and industrial infrastruc- ture. This expenditure on infrastructure does not have to be

Jan 1, 1975

The Transportable Moisture Limits, as ,measured by the procedures laid down in The IMCO Code of Safe Practices for Bulk Cargoes, determine the target moisture contents for the concentrates produced at the West Coast Mines of Electrolytic Zinc Company of Australasia Limited at Rosebery. Filtration of these concentrates gives moisture contents considered to be low in comparison with those achieved for similar sulphide concentrates, but which are very close to these Transportable Moisture Limits. The filtering techniques used are outlined and the problems associated with-maintaining concentrate moistures below the required limits, together with the methods used to solve these problems are discussed.

Jan 1, 1978

By R Trueman

An improved ability to predict dilution for narrow vein deposits enables more accurate economic comparisons between mechanised longhole stoping and other narrow vein mining methods, as well as reducing uncertainty surrounding dilution estimates for deposits at the prefeasibility/ feasibility stage. This paper proposes narrow vein dilution prediction and minimisation strategies for both greenfield sites and operating mines, respectively. The narrow vein dilution method (NVD method) is a tool for more accurately predicting longhole narrow vein dilution. The method is based on a new concept called benchmark stoping width. Benchmark stoping width is based on probabilistic analysis of overbreak distributions from a typical longhole narrow vein mine. The premise for the NVD method is that dilution associated with longhole stoping can be predicted using the benchmark stoping width. In addition to dilution prediction, the NVD method also includes strategies for narrow vein dilution minimisation generally, including; filling, cablebolting, stress relaxation, extraction sequencing and blast overbreak.

Jan 1, 2008

By Jimbo I, Ogawa O

A series of experiments was carried out to investigate the solubilities of copper, arsenic, antimony and bismuth in silica-saturated iron silicate slags under controlled oxygen partial pressures at 1200 and 1250¦C. Molten copper containing each of the above elements was kept in contact with a slag in a silica crucible for 24 or 48 hours to attain equilibrium. No me- chanical entrapment of metal into the slag was observed. The appearance of the magnetite phase in the slag was avoided by holding oxygen potentials at substantially lower values than that evaluated from available data on iron silicate slags. Solubilities of copper, arsenic, antimony and bismuth in slags were plotted against oxy- gen potentials and both oxidic and atomic types of dissolution were found, except in the case of arsenic, from the dependencies of the solubili- ties on the oxygen potential and from positive intercepts of regression lines when extra- polated to zero oxygen potential. The dissolu- tion of arsenic seemed mostly oxidic. Distri- bution coefficients of arseò,ic, antimony and bismuth between copper and slag are also Discussed.

Jan 1, 1980

By Choulaj D

Mining and petroleum continue to be the two most vita components of our nation's development, says Sir Julius Char in the Australian Journal of Mining (Nov-Dec 1996). In fact the} account for 71.6% of export earnings, and 21.2% of Gros; Domestic Product in Papua New Guinea. The Misima and Porger, Mines, along with the Kutubu oil project, have essentially rescues PNG's economic viability since the loss of income from Panguna Though the industry cannot create employment in the manner o. intensive industries such as agriculture, it does provid( opportunities to local communities in terms of jobs, financia compensation, and infrastructure. Many ventures take many years and enormous capital investment to set up. There are three phases: exploration, feasibility, an( operations. The operations phase sees a massive development o infrastructure, or the actual `building' of the mine. For mining companies to commit to such lengthy time frames and high level: of investment, without returns, requires confidence and a degree of commitment from government on a number of levels - legislative stability, monitoring social development, and the provision o social infrastructure.

Jan 1, 1997

It is my pleasure to deliver the first Keynote Address to the first joint conference between The Australasian Institute of Mining and- Metallurgy and The American Institute of Mining, Metallur- gical and Petroleum Engineers. I am particularly pleased to be participating in this first joint meet- ing as I have been a member of one Institute for 41 years and the other for 35 years. An examination of the membership of both Institutes confirms the fact that the mineral in- dustry is an international one. This has long been the case and basically stems from the occurrence of mineral resources in most countries of the world. It is therefore fitting that these two 'Inter- national Institutes', representing the professions involved in the mineral industry, should choose `International Resource Management' as the theme of the first joint conference. The topic of this Keynote Address is `The mineral equation' or the counterbalancing supply and demand items and the factors affecting them. I propose to attempt to present the overall picture of the mineral equation as subsequent papers and sessions will deal with specific items in more detail. My thesis is broad and deceptively simple; it is that the continued existence and growth of world material civilization depends, in large measure, on the continued use and further dis- covery of world mineral resources. Material civili- zation is used as a broad term to include the pro- duction of man's shelter and tools together with the production of the `consumer' goods and ser- vices needed by society. First let us spend a few minutes looking at the development of material civilization.

Jan 1, 1978

By Hutchinson IN

In order for the Australian underground coal mining industry to achieve the high productivity rates demanded of it without compromising its good safety record, improved geotechnical monitoring systems are required. One of the main problem areas affecting underground coal mining is the deterioration of previously stable roadways.CSIRO Division of Geomechanics has been working on a NERDDC funded project to develop an instrument to monitor coal mine roof deformation. The instrument which has been developed, Roof Alert, is a self contained, battery powered, intrinsically safe device. It can monitor the magnitude and rate of deformation and give multiple, variable visual alarm signals where preset levels ate exceeded.

Jan 1, 1991

Deposits of manganese oxides and silicates in the Tamworth area were re-examined. The major deposit at Danglemah consists chiefly of rhodonite and the rare silicate tephroite. It is considered that the manganese was deposited with the original sediments, the silicates being formed later during the intense folding and low-grade metamorphism of the enclosing rocks.INTRODUCTIONMany small deposits of manganese oxides and silicates occur along a belt of eastern New South Wales and Queensland.Some fifty occurrences, most of which have been subject to mining activity, were described by Lloyd (1943) and some of this information was summarized by Knight (1947). The ores have been mined on a small scale since 1884. Small supplies of battery grade ore were won from a number of deposits, while larger quantities of metallurgical grade were sold to the steel industry. Maximum production was in 1918, when 6,500 tons were mined.The siliceous nature of many of the ores and their occurrence in the neighbourhood of granite batholiths led earlier investigators to consider the deposits to be of hydrothermal origin, associated with the granite intrusions. The present work questions this viewpoint.In this investigation, three of the chief deposits in the Tamworth area were seen. These were at Danglemah, which is being mined at present, and Mount Jasper and Manganese Mountain, which were mined in the past. The Danglemah mine is the most accessible and yields the best material...

Jan 1, 1962

Early in 1930 William S. Robinson, Managing Director of Zinc Corporation Ltd., anticipated a rise in the price of gold and a devaluation of the Australian currency. 'WS', as Robinson was known, formed a.syndicate in London, which later became incor- porated as Gold Mines of Australia Limited (GMA) to invest in gold mining properties in Australia. GMA examined many prospects and subsequently undertook the development of several mines in eastern Australia. The syndicate also held a number of options and several large reservations for gold exploration in Western Australia over which it was proposed to carry out an aerial survey and thorough scien- tific assessment. To do this Western Mining Corporation Limited (WMC) was incorporated in Melbourne on the 2nd March 1933. The founding chairman of WMC and GMA was the highly respected `Collins House' figure, Sir Colin Fraser. The aerial survey was carried out, and a group of eminent geol- ogists from Harvard University examined many prospects and identified several which warranted development. To finance these activities `WS' formed Gold Exploration and Finance Co. of Aus- tralia Ltd. (GEFCA), in London in July 1934. GEFCA ultimately held 95% of WMC and 62% of GMA. The finance came mostly from London based South African mining companies which had been subscribers to his earlier syndicate plus some American inves- tors. (The Group Structure in 1936 is shown in Appendix `B").

Jan 1, 1988

By B Bendtsen, L McQueen

The use of shotcrete as an efficient means of both temporary and permanent ground support has continued to grow over the last 30 years, with its use underground now commonplace around the world. However, the development of analytical design methods has lagged advances in material and application technologies. Historically, part of the reason for this was a lack of understanding of how shotcrete linings actually worked. Considerable progress has been made in this area in recent years and this paper attempts to summarise the current state of practice with respect to shotcrete lining design. It then concludes by summarising areas where the authors consider future research and development is still required.

Jan 1, 2008

By P Elliott, D Pershke

In a minerals processing context, sustainability is about using natural resources more efficiently to achieve maximum economic benefits with minimal environmental impacts. It embodies five overarching themes, which the paper will illustrate with practical examples from Australian minerals processing plants. These are:resource utilisation and materials efficiency,process waste reduction and enhancement of co-product values,reduction of water use and impacts,reduction of energy requirements and greenhouse gas emissions, andenhanced control of minor elements and toxic materials. Sustainability could be embedded profitably in minerals plant design in three dimensions: 1.technology,2.design, and3.operations. This presentation discusses a set of principles that could be applied to minerals processing technologies and provides an outline of sustainability assessment and opportunities evaluation tools. The application of the tools is illustrated through a case study by analysing a suite of nickel processing technology routes. The analysis reveals that current generation of nickel processing technologies do possess real potential to emerge as sustainability champions in integrated processing of nickel ores and concentrates, if they are designed, engineered, and operated for sustainability and adapted effectively to site specific constraints and opportunities. The paper will address data gaps and uncertainties regarding the impact of scaling up of pilot-plant performance, and provides strategies to overcome them.

Jan 1, 2006

By M G. Aylmore

Thiosulphate is an attractive alternative reagent to cyanide for processing gold ores. It is relatively cheap and non-toxic, forms relatively strong gold and silver complexes, and readily leaches gold ores in ammoniacal solutions, catalysed by Cu(II). It is particularly suited to carbonaceous ores where the recovery of gold by cyanide is poor. However research over the past 20 years has identified a number of issues and impediments that must be understood or overcome before an overall process can be demonstrated as practical and economic for typical oxidised gold ores. This paper reviews our current understanding of thiosulphate chemistry and mechanism of gold dissolution, and discusses the stability of thiosulphate and polythionates. It then reviews the results of leaching various gold ores that have been reported in the literature, discusses gold recovery options, and considers environmental and toxicity issues. Some of the issues that require further research include decreasing the oxidation of thiosulphate by Cu(II) or other oxidants, increasing the extraction of gold compared to cyanide, and understanding the variation in gold recovery between ores. More work is also required to minimise the effect of polythionates on gold recovery using resins or alternative absorbents, to improve the elution of copper and gold from resins, and to recycle or minimise the concentration of reagents.

Jan 1, 2002

According to the temporal and spatial distribution of regional metallogenesis, the Pacific Rim can be divided into four global metallogenetic systems. The Asia-Australia W-Sn metallogenetic belt is the typical representative of intracontinen- tal metallogenetic systems. This belt resulted from Mesozoic and partly pre-Mesozoic tectonic magmatism, mainly re- lated to S-type granite of crustal source, that was generated by collisional orogeny combined with oceanic subduction in intracontinental and continental margin settings. Based on the concept of metallogenetic series, there is a group of min- eralised ore types showing a definite spatial and temporal distribution from endogenetic to exogenetic. These metalloge- netic series are widely distributed in the Asia-Australia W-Sn metallogenetic belt, and are well developed in Southeast China. Five metallogenetic series and two petro-minerogenesis evolution models have been established according to their tectonic settings, various types of granitoids and metallogenetic evolution.

Jan 1, 1995

THERE is available a considerable amount of literature concerning the practice, and, to a smaller extent, the theory of ventilation as it applies to coal mines. Publications considering the subject of ventilation of metal mines from a practical viewpoint are much less numerous, whilst the treatment of the theoretical aspect of the question (except in so far as is common to coal mining) appears to have been almost neglected. This may be due to one of two causes (a) That in many metal mines (especially those which have not attained a great depth), on account of the greater number of connections with the surface, as compared with coal mines, natural ventilation has sufficed.(b) That in metal mines where the foregoing is not the case the solution of the ventilation problem from theoretical considerations has been regarded as involving so many complications that any attempt at the determination of a set of concrete ventilation figures applying to and throughout the mine would be futile. Whilst it is freely admitted that the difficulties inherent in the application of theory to the ventilation of metal mines are numerous, it must also be admitted that few attempts have been made to overcome them. The ultimate aim, of course, would be the collection of sufficient data to enable the probable behaviour of the air-currents throughout the whole of the workings of any mine to be accurately predicted under any particular set of circumstances. Failing the attainment of this goal of perfection, it would at least appear that much valuable information might be obtained. In ventilation, as in...

Jan 1, 1921

By A S. Bamber

Mining is the oldest industrial practice on the planet with a history dating back over 3000 years. Since the early iron age ores have been extracted for use in a variety of contexts by humankind, from domestic to military, transport and more recently for complex industrial applications. Mineral exploration and extraction has evolved from the early exploitation of primary metal occurrences in relatively small quantities such as iron, gold, coal and copper, to the bulk mining and extraction of highly complex polymetallic oxides and sulfides today. Since the industrial revolution, mining practice has evolved substantially to support an increasing range and quantity of required metals and to accommodate the increasing scarcity of high-quality sources of these metals. A common response to the increasing scarcity of mineral resources has been to expand production through simple economies of scale, thus diluting fixed costs. This approach, however, is increasingly ineffective in the face of current trends, that include increasingly complex mineralogy, increasing pressure on environmental footprint - energy in particular, and increasing scarcity of capital for the construction of presently popular æmega-minesÆ. This paper examines historical trends and current practice in mineral exploitation in the light of the current global revolution in social, environmental and economic values as the projects move towards a vastly different topology for the industry for continued success in years to come.CITATION:Bamber, A S, 2012. The mining industry needs to be shaken and stirred, in Proceedings Narrow Vein Mining 2012 , pp 3-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

This paper contends that optimisation of energy resources through active control and predictive simulation modelling is possible, and that such monitoring leads to large savings in the electricity costs of hot mines (where refrigeration has to be employed). In addition, active monitoring and control can positively affect the establishment of a safe, healthy and productive working environment. In the entire optimisation process certain guidelines were set to ensure that the requirements of the Mine Health and Safety Act were met (South Africa). Varying the quantity of air supplied underground by means of variable speed drive (VSD) fans is one of the crucial factors in the interactive approach towards the optimisation of ventilation, as is refrigeration and the pumping requirements associated with refrigeration. This article highlights the interaction between the amount of air supplied and the effect it has on refrigeration requirements underground. This article also considers the effect that this would have on contaminant control. Various tools are available for ventilation and cooling design for mining. A lot of these tools are based on the assumption of steady state conditions and do not take into account instantaneous changes in conditions, day-to-day, or hour-to-hour (such as for temperature and contaminants). They also do not take into account the optimisation of energy resources related to the creation of the acceptable underground conditions. With these tools worst-case and best-case scenarios are identified, and strategic decisions are made accordingly. Currently, the amount of the fresh air, the velocity of the air, and its general temperature in the mine are only changed when one production phase changes into another (or when unacceptable conditions occur as a result of poor design or neglect). This means that during a specific production phase (which can last for several months), there can be an oversupply, or undersupply, of energy resources, which will obviously affect the concentration levels of the various contaminants (through under or oversupply of air).

Jan 1, 2005

We can look at the water treatment and management strategies at some recently commissioned mines and minerals processing sites to see the likely future of water in mining. The future of water in mining will be based on a holistic approach to understanding the site water balance, appropriate treatment, reuse where possible, and environmentally managed discharge where required. This paper describes advanced and innovative water treatment and reuse processes as used by mines and mineral processing operations from around the world. Underground mining can often require dewatering to prevent groundwater seeping into and flooding the mine workings. Mining and processing often accumulates wastewaters in a tailings dam. The mine water can contain contaminants such as dissolved salts, iron, arsenic, manganese, heavy metals and acidic and odorous sulfates. On-site reuse, environmental discharge requirements, as well as community needs for water, drive mine operators to consider the most appropriate water treatment process. Mining water treatment for the future is described using case studies of innovative processes. The case studies include treatment of mine dewatering water for beneficial application from Australian mines, Ballarat Goldfields and Bendigo mining, treatment of produced water from oil and gas projects, and treatment for arsenic removal of tailings water from mining and processing at Goldcorp mines in Canada. Advanced and innovative processes including membrane filtration, reverse osmosis at extreme conditions, advanced biological treatment and water management are all part of these case studies. This paper uses real case studies of advanced and innovative mine water treatment processes to explain and examine the technology and the reasons for designing specific processes. The focus is on innovative processes that may be more widely used in future mining û where the water is used for sustainable environmental discharge or treatment to a quality that can be beneficially used by the mine or the local community.

Jan 1, 2008