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My topic for today is the Crown Minerals of the future. New work initiatives are underway and the organisational structure is being overhauled. These are not insignificant changes and in this paper briefly summarises these proposals. These new work initiatives and changes to the organisational structure will have implications for the industry as a whole and also for the way individual clients interact with Crown Minerals.

Jan 1, 2003

By M van Kampen

The Resource Management Act 1991 has been amended on a number of separate occasions since its enactment in 1991, and has recently be subject to further amendment by way of the Resource Management Amendment Act 2005. The amendments as proposed in the Resource Management and Electricity Legislation Bill would have had revolutionary and far-reaching consequences. However, as finally enacted, the amendments are a greatly watered down version of what was initially proposed.   Nonetheless, the Resource Management Amendment Act 2005 has provided for a number of amendments that will impact on the minerals industry to varying degrees. This paper discusses in particular the changes and impact of the changes to the definition of æcontaminated landÆ, clarification with respect to the duty to consult, amendments to the provisions relating to National Environmental Standards, and to the council and Environment Court hearing process.

Jan 1, 2005

Mineral sands are being used as the source material for new "high-tech" engineering materials. One such material, Magnesia Partially Stabilized Zirconia (PSZ) has been developed and patented world-wide by CSIRO. Derived from zircon sands, the material is currently produced by Nilcra Ceramics in Australia and is exported world-wide.The properties of the material are contrary to those generally accepted for ceramics and are far more akin to those of steel. The material resists not only abrasive wear, impact and thermal shock, but does so under corrosive conditions that frequently cause early failure of metal and cemented carbide.While the consumption of mineral sands for the production of PSZ is not going to significantly increase the demand in the short term, the material itself may well assist the productivity and processing problems within the industry.

Jan 1, 1986

In recent decades the awareness of environmental issues by the general public has developed at an accelerat- ing rate. This is the result of a number of factors including more scientific knowledge of environments and of the impacts of modern society upon them, higher levels of education, the opportunity for people to travel more, and the success of the various communication media in bringing in- formation to the communities of the world about such environmental crises or threats as the smogs of Los Angeles and London, the Torrey Canyon and Santa Barbara oilspills, Minamata disease in Japan, the spread of the Crown of Thorns starfish, the disposal of toxic industrial wastes into the Upper Rhine, the discovery of high mercury and zinc contents in marine foods in southern Australian waters, and the proposal to mine limestone at Precipitous Bluff in Tasmania.

Jan 1, 1975

What is the best circuit to comminute primary crusher product to make beneficiation feed? Finding the best circuit to crush and grind minerals to beneficiation sizes is a complex problem that can lead to interminable discussion. Conclusions reached can be questioned. This will continue as long as the technology of comminution continues to expand, and is a mixture of many technical and economic factors in what is not a precise science. Laboratory and pilot plant procedures now exist that can help process engineers make sound decisions on which circuits are the best for crushing and grinding the specific ore being studied. It is the aim of this paper to discuss such procedures so a better under- standing of key decision parameters is avail- able, and to update comminution testing which has seen a. period of change in which new procedures have been introduced.

Jan 1, 1978

By Jia X

Three-dimensional microscopic modelling techniques involving specific calculations based on direct computation of the Brownian, van der Waals, Born, electrical double layer repulsion, bulk, hydrodynamic and external forces (gravity, magnetic etc) acting on and between each particle in a mineral dispersion are now feasible using advanced computer processor architectures. This contribution surveys the hardware requirements, the advantages and limitations of the approach for enabling prediction of dispersion behaviour a priori. The notion of developing a generic particle simulator, akin to the use of molecular modelling in the area of drug design, based on inputting process-relevant data (solution chemistry, mineral solids properties, hydrodynamics etc) is discussed. The methodology is illustrated with application examples involving: predictions of coagulation of mineral fines; shape and size of magnetically-flocculated hematite; and the kinetics of fouling of membrane surfaces and walls.

Jan 1, 1993

By E Drueppel, M Mistry, J Pateiro

As mining undoubtedly influences the natural environment future challenges of copper ore mining are minimisation of land use in area and duration, proper land rehabilitation as well as tailings management. One possible solution to avoid these negative impacts could be the application of underground mining with backfilling tailings compounds. This approach would definitely increase the production cost. Against this background the project analyses the influence of an æecologically satisfyingÆ copper ore mining on world market prize and demand as well as on the environment. In the project 261 copper ore mines accounting for 98 per cent of world copper production have been examined. After modelling a backfill plant, analyses of applied backfill techniques were conducted. Afterwards a method of cost estimation was developed and then the backfill plant model was applied in three case studies. The results were transferred into scenarios. The work closes with a short discussion and gives an outlook to forthcoming research. The results presented in this work have been generated within the Collaborative Research Center (CRC) 525 entitled æResource-orientated view of metallic raw material flowsÆ. This interdisciplinary project was established at Aachen University of Technology (Germany) in 1997 and is funded by the Deutsche Forschungsgemeinschaft (DFG). The long-term goal of this research program is the identification of options for the resource-sensitive supply and processing of metallic raw materials. In order to address the sustainable development challenges facing the metals and minerals industry an integrated resource management system is to be developed and tested for important metallic raw materials. Case studies for aluminium and copper are being conducted by the CRC 525 in order to provide useful and efficient tools for decision makers over the entire life cycle of these materials.

Jan 1, 2003

By F R. A Jorgensen, G W. Jensen

A pilot scale experimental investigation of the condensation of zinc vapour from smelter off-gases was performed in conjunction with a mathematical modelling study of the system. The work investigated the feasibility of using the high heat and mass transfer rates associated with a fluidised bed to condense zinc directly from smelter off-gases containing zinc vapour. Of particular interest was whether zinc would revert to zinc oxide during the process of condensation, and whether a zinc fog would form and be carried out of the condenser. A 0.1 m diameter fluidised bed condenser was mounted on the top of a 200 kVA DC electric arc furnace in which mixtures of vapours and gases were generated at 1150 - 1300¦C. The gas/vapour mixtures investigated included Zn/N2, Zn/N2/CO/CO2 and Zn/N2/H2/H2O. Greater than 90 per cent of the zinc was deposited on the zircon sand bed of the condenser, and there was no sign of zinc oxide formation, suggesting that the rate of heat transfer was faster than the reaction rate for zinc oxide formation. There was also no evidence that fog was being formed in the condenser. Using the methods of Kunii and Levenspeil (1991), a mathematical model was developed to predict the behaviour of the fluidised bed condenser. The model enabled the distribution of gas/vapour temperature and bed temperature to be determined as a function of distance from the condenser inlet. Similarly the partial pressure of zinc vapour in the gas mixture, and hence the mass transfer rate of zinc to the particles, was determined. Experimental data allowed validation of the predicted bed and gas/vapour temperatures.

Jan 1, 2000

Airblast overpressure legislative limits can be extremely difficult to meet throughout Australia, which has by far the most stringent limits of any nation in the world. As the difficulty in meeting the limits is strongly dependent on the scale of mining, it is not surprising that the Australian coal mining industry is experiencing particular difficulties in meeting these limits. Eight full scale overburden blasts have been modelled with respect to overpressure impact for a strip coal mine, involving both dragline (cast) blasting and pre-strip (non-cast) blasting. Overpressure levels in the range 100 to 125 dBL have been measured at distances varying from 2.4 to 5.7 km, and modelling has successfully estimated both the amplitude and shape of overpressure waveforms to within an average of 1.2 dBL. Typical errors of prediction are around 0.6 dBL. This accuracy of prediction has been achieved by considering the impact of only the face holes, and the accuracy of prediction of both shape and amplitude suggests that it is these holes which dominate the environmental overpressure impact at distances in the range two to six kilometres, for cast and pre-strip blasting operations. Modelling has been based upon the Elemental Overpressure Wavelet proposed by Richards and Moore (2002), incorporating actual hole coordinates, actual delay timing, and assumed delay scatter statistics. The incorporation of delay scatter statistics has been particularly significant, and allows the determination of the range over which the peak overpressure levels are expected to vary. To date, modelling has considered only the use of conventional pyrotechnic delays, though simple adjustment to the scatter definition would allow estimation of overpressure levels, and their variability, with electronic delays.

Jan 1, 2004

By Fountain C. R

In April 1987, Mount Isa Mines Limited (MIM) commissioned an ISASMELT reactor to smelt 15t/h of copper concentrate at the Mount Isa Copper Smelter. This unit was based on the Sirosmelt lance technology and incorporated features proven in the Lead ISASMELT plant which has been operating in the MIM Lead Smelter since 1983. From April 1987 to June 1989, the copper smelting plant treated 167000 tonnes. Concentrate, coal and fluxes are fed continuously to the furnace. Oxygen enriched air is injected through a lance which is submerged in the slag bath. Matte and slag are tapped together through a single taphole into a reverberatory furnace, and from there are treated with normal reverberatory furnace production. Advantages of the process include its ability to eliminate most lead and arsenic in feed, its flexibility with respect to feed composition, sizing and moisture, and the plant's low capital cost. Acceptable refractory life has also been demonstrated. The commissioning of a 70 t/day oxygen plant has rerated the plant from 15t/h to 18t/h while allowing a reduction in fuel usage of one third. A trial using 150 t/day oxygen was carried out in May 1989, and showed that the furnace could treat 48 t/h chalcopyrite concentrate while maintaining a very low fuel requirement. The oxygen trial results have given considerable confidence for plant scale-up. Detailed project evaluation is currently underway for the replacement of the roaster and reverberatory furnaces at Mount Isa with a single 110 t/h ISASMELT reactor.

Jan 1, 1989

Gold mining in Waihi spans three centuries and five generations. Following the discovery of gold in 1878 the Martha Mine was developed and the town of Waihi grew up around it. Now, five generations later, descendents of many of the original settler families continue to live and work in Waihi. Many have returned to mining, in jobs far removed from those of their parents or grandparents.   Members of three local families were interviewed on video. This paper is a summary of some of the major themes and gives some insight into the role gold mining played in the development of the region and its continued its importance today.

Jan 1, 2006

By T Harrington, M Cox

There have been many changes in the Australian mining industry during the last 30 years. One of the most dramatic changes, from a geological perspective, is the reduction of in-house geological staffing and an ever increasing reliance on contract and consulting services. As a result, there has been a change in the way geological information is generated, managed and retained within the industry. This paper describes the changes that have taken place in the industry, provides two case studies of how companies manage their geological Intellectual Property and reviews some of the issues associated with management of in-house and outsourced geology services.

Jan 1, 2009

This report on the 5th International Conference on Underground Space and Earth Sheltered Structures, which was held at the University of Technology, Delft, the Netherlands, on 2 to 5 August 1992, was submitted to the members of the Australian Underground Construction and Tunnelling Association. The report describes the conference themes and outcomes and puts forward some observations about a growing world-wide interest in the promotion of appropriate uses of underground space. The report recommends the creation of an Australian centre for research to bring together a wide range of professional disciplines and to focus attention on the potential benefits of using underground space.

Jan 1, 1993

By Wadsley MW

This paper gives an overall view of the CSIRO-SGTE computer system for thermodynamic calculations. The basis of the system is the coupling of a large self-consistent numeric data bank of thermodynamic information to a modular set of application programs. These seven programs cover management of data files, calculation of thermodynamic properties for species and reactions, plotting of predomin- ance area diagrams, equilibrium and enthalpy balances for complex processes, analysis of thermodynamic efficiency and the estimation of unknown properties. The data bank contains a wide coverage of species and data types so that the system may be applied to many areas of chemistry and metallurgy.

Jan 1, 1984

By Simes C. D

Results of experiments for dissolution of zinc by aeration of sphalerite in glass, copper, galvanised iron and stainless steel vessels of identical dimensions are reported. It was found that in a glass container dissolution of zinc reaches a maximum after 30 min aeration and then decreases whereas in the copper container dissolution remains nearly unchanged up to 30 min aeration and then increases. In the cases of galvanised iron and stainless steel containers zinc dissolution increased steadily with time up to 60 min aeration. It is suggested that the different rates of dissolution in glass and copper containers may be due to electro-chemical actions.

Jan 1, 1984

By Kershaw M. G, Maughan R. C A

A process for eliminating nickel from electrolytic zinc plant solutions by precipita- tion with dimethylglyoxime (DMG) was developed to enable the Electrolytic Zinc Company of Australasia Limited (EZ) to treat nickel-bearing zinc dust precipitates. These precipitates are leached to recover their Cd and Zn content. The final Zn bearing solutions contain relatively high Ni concentra- tions (20-100 mg/1) and are treated with DMG and then neutralized to pH 4.6-4.8. The pre- cipitate is filtered off and the solution returned to circuit. DMG consumption is about 200% of theo- retical requirement, and Ni removal is 80% complete overall.

Jan 1, 1977

Dealing with Aboriginals and various others purporting to represent them has become part and parcel of exploration and mining in Australia, whereas 20 years ago it was not. The author has been involved in dealings with Aboriginal groups over this period. The following paper is a summary of the social background to such dealings and a compendium of rules for the newcomer to this aspect of the resource industry.

Jan 1, 1990

By Runge IC

The mine planning process is reviewed and appropriate software considered in terms of "line process" or "support function". The mine planner's requirements of a geological model and the elements of and requirements of a computerised mine planning system are all discussed. The use of "support" software for mine planning is considered and general rules for its development are given. Important changes involved in implementing a computerised mine planning program are listed.

Jan 1, 1983

By Haartti J

Generally when equipment is chosen for solving a dewatering problem, the equipment is based on one of following physical methods: gravity (sedimentation, screens), vacuum (vacuum drum and disc filters, belt filters), pressure (filter presses, hyperbaric filters) and centrifugal forces (centrifuges). The choice of method and type of equipment depends, among other things, on the requirements on the maximum water content allowed in the filter cake and on the particle size distribution and the concentration of solids in the material to be dewatered. All the above-mentioned equipment has its benefits and drawbacks. The conventional vacuum filters of drum or disc type are of a simple construction with few parts to be replaced, but these filters produce a filter cake with a fairly high moisture content, and a dryer is required for additional drying. In most cases the use of pressure makes it possible to produce filter cakes with the desired moisture content but the equipment is of complicated construction, leading to high maintenance costs . In addition to this the consumption of compressed air is high. The capillary filtration to be described in this article is a dewatering method which combines the benefits of both the conventional vacuum disc filter and the filter press. The capillary filter produces low cake moistures with a machine of very simple construction similar to that of the vacuum disc filter.

Jan 1, 1993

By N Ozawa, R Kaneko, M Arimit

The Mitsubishi Higashitani limestone mine is a ten million tonne per annum operation located near the city of Kitakyushu on JapanÆs western island of Kyushu. Higashitani is one of the largest limestone mines in Japan and accounts for about five per cent of national production. Blasting practices at the Higashitani mine involve the use of bagged ANFO, dynamite primers and non-electric detonators. Regulations in Japan prohibit the use of site mixed bulk explosives. Blast size is usually around 17 000 tonnes with 20 holes in a single row, two or three blasts are fired per day at a powder factor of between 0.25 and 0.32 kg/m3. As part of a program looking at oversize reduction Mitsubishi, Asahi and Orica agreed to conduct a joint project at the Higashitani mine to investigate the relationship between the powder factor and fragmentation. The first stage of the project was to benchmark the current blasting performance. Five blasts were monitored in each of the 210 (hard rock) and 220 (soft rock) areas of the mine. OricaÆs Powersieve« software was used to measure fragmentation and total rock breaker hours were also recorded for each blast. OricaÆs computer blasting simulation model Sabrex« was used to prepare revised blast designs with a higher powder factor and predict their performance. The performance of these blasts was monitored using the same methods.

Jan 1, 2004