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Part of a four-year course in metallurgy, dealing with metallurgical process engineering, was designed for students to acquire knowledge and skill from physical science, metallurgy, process engineering, and social science. Principles of education, and guidelines obtained from a study of professional practice, indicated that students may learn effectively through a planned sequence of problem-solving exercises based on the diverse functions of metallurgists in industry. The more important characteristics of the curriculum and a few illustrations of the problems are included. An outline is given of the current procedures used to develop parts of the curriculum, and of the students' diffic- ulties and achievements.

Jan 1, 1984

My closest personal connection with the problems of rehabilitation comes from two years spent on a project at Weipa. At the beginning I am fairly certain that the engineers did not understand the mental processes of the ecologist they were dealing with. I am absolutely certain that the ecologist did not understand the minds of the engineers. This form of the two cultures problem is the root of some of the matters that lie behind this lecture. It is possible to establish a stabilising cover of vegetation on virtually any land surface, short of a cliff. While the biologist knows this he also knows that the physical and chemical nature of a given acre of land combines with climate to define quite sharply just what plants can be grown there. In the case of land after mining the range of plants may be quite limited. The engineer, and his masters in the accounting section, seem (in my experience) to expect that rehabilitation can be carried on with equal speed and facility in any location. This belief commonly leads to a situation where rehabilitation is not considered until mining is well under way. True, the mine must be proved as an assured profit- earner before money can be justified for the non-productive (to the miner) expense of rehabilitation. But when the miner finally starts rehabilitation he does not always get a convincing and speedy result. Furthermore, the failure may not be easy to overcome. This is even more likely to be the sequence of events if the miner wants, or is obliged, to specify the exact type of vegetation to be produced, e. g. commercial forest, pasture,' or the original native vegetation.

Jan 1, 1971

There is very little in Australian mining law that sets out the rights of mining tenement and exploration licence holders as against other parties who wish to carry out ground or aerial surveillance over those areas.There have already been several legal actions arising out of this lack, and more can be expected as the public places more rigorous constraints on corporate and individual behaviour. Field personnel, who are mainly fairly junior and less experienced, are entitled to some guidance from the minerals industry, guidance which up to now appears to have been either lacking or covering such a wide range of standards from corporation to corporation as to be virtually useless.Because each State writes its own laws there is no consistency, and the laws generally are lagging behind developments in the industry. In particular, the practice of granting mining tenements for sporadic exploration, a practice that is a leftover from much earlier mining law, has dotted the Australian continent with unattended and unmarked or poorly marked tenements that are difficult to find but confer on the holder prior rights to the minerals under them. Entry onto those areas in most jurisdictions is an offence and their existence compromises the efforts of regional explorers.This clearly unsatisfactory situation requires remedying, which is the purpose of these proposals. A more systematic approach to the granting of reconnaissance, regional and detailed exploration, mining, and retention rights will eliminate much of the problem. For the rest, a code of practice needs to be adopted as soon as possible.

Jan 1, 1996

Australia had been enjoying a market boom led by the mining sector and West Australian mines were leading the way to satisfy the massive demand for our natural resources, especially from China. However, the Apache gas explosion on Varanus Island, 97 km off the west coast, has clearly demonstrated how the unexpected can suddenly impact on profitability and investor confidence for the mining industry. Risk management with contingency planning can provide the most cost-effective solution to help ensure mining projects are successful. For this discussion we will focus primarily on contingency planning, CP for mining projects à and how to plan for the unexpected. The Apache gas explosion will be our example æUnexpected EventÆ. Insurance may provide financial compensation but it will not protect your reputation as a reliable supplier or prevent damage to investor confidence and future mine projects. However, contingency planning can provide real protection for mining projects à to survive the unexpected.

Jan 1, 2009

In many mining operations, the truck and loader equipment represents the bulk of the invested capital and the majority of the mine operating cost. The profitability of these mines is therefore critically linked to the efficiency of the truck and loader operations. The various factors which affect the productivity of trucks and loaders are analysed by computer simulation, and the results presented in a form allowing assessment of the importance of each factor on overall productivity.

Jan 1, 1983

By Browner R, Kyle J

The adsorption of gold cyanide by the weak base ion exchange resins, PAZ-4¦ and Duolite A-7C, the neutral polymeric adsorbent, Amberlite XAD7¦, and the strong base resins, PAZ-8~a and IRA-400 have been studied in both low and high salinity waters, and their performance compared with activated carbon. A systematic study has also been made of the effect of different ions (Na+, Cat+, Mgt+, Cl', SO4) ) on the gold adsorption capacity and kinetics of these resins. The results indicate that, contrary to popular belief, the ion exchange resin, can perform effectively in highly saline environments. The performance of the neutral polymeric adsorbent im- proves with increasing salinity but cannot match the performance of the ion-exchange resins.

Jan 1, 1991

By Leggate J

In the past many coal mining projects commenced without any consideration being given to eventual site rehabilitation. Now that site rehabilitation is assuming greater importance with changing community expectations, and standards are becoming less negotiable, it cannot be ignored in either the development of mine working plans or economic models. The "unspecified" rehabilitation measures associated with many existing projects will be the subject of debate for some time to come yet. It would be wise to plan for the future. Once an agreeed standard of rehabilitation is accepted, good management involves considering practices which will facilitate eventual rehabilitation at least cost. Without planning for rehabilitation, many mines have adopted practices which are likely to result in very expensive rehabilitation measures and impact significantly on the overall profitability of the ventures. With adequate planning, procedures can be developed which achieve the same short term goals without significantly effecting cash flow but with very significant impacts on the final rehabilitation cost. This paper looks at the disposal of tailings and overburden in the coal mining process. The industry has in the past had an obvious preference for the "perceived" cheaper procedures for waste management such as wet disposal of tailings and high dumping of overburden. There are alternatives. The paper discusses the principles which should be incorporated into tailings and overburden disposal systems and identifies viable alternatives.

Jan 1, 1991

By M B. McKevitt, W J. Shaw

The main task of grade control on a daily basis is to define the material that should be mined to a destination under various categories. This can be determined by grade, lithology, quality and blending criteria. In the case of multi-element deposits or deposits with various blending or other processing criteria the optimum selection of ore block boundaries can be quite complex. In every case the balance between ore loss and dilution must be considered when designing the ore block boundaries and this becomes a risk-based decision when using the conditional simulation model. The use of such systems allows grade control to meet specific targets, such as budget tonnages and grades and blended product specifications. Two case studies are presented: the Prominent Hill copper/gold mine and the Rapu Rapu zinc/copper mine. Mining is based on a rational grade control strategy involving a number of factors, including strong geological control, advanced geostatistical approaches, such as conditional simulation, and optimisation of the ore blocking to meet production requirements. This provides an objective, transparent and repeatable grade control strategy.

Jan 1, 2009

Performance driver trees or KPI trees are reasonably well-known tools for analysing performance in mining operations. However, the tools are often not user friendly. They may be technically correct but they are often clunky. This means they donÆt promote simple management decision-making and donÆt encourage businesses to make them an integrated part of optimising their operations. This paper describes a simple but effective driver tree process and tool that has been successfully implemented and used to aid decision making across a number of mining and processing operations. The important aspects of employing driver trees to assist in management of operations are to ensure that the chosen solution:includes a reporting solution, provides the bottom line impact of the performance indicators, automatically gathers the necessary data that reconciles with existing reports, and is built around a review process that fits with existing management processes. An adequate solution enables operators to identify where there are performance gaps and to quickly prioritise the urgency for addressing these issues. Two case studies are chosen to illustrate the critical success factors of implementing a performance driver tree solution. The first is a large, complex open pit operation. The driver trees, reporting and management processes were initially established for the mining and processing aspects of the operations. Once the initial solution was bedded down, a follow-up project was carried out to establish the equivalent solution for the support areas of the business. The final solution covered stand alone performance driver trees for mining, processing, engineering, maintenance, health and safety, human resources and finance. These individual driver trees were integrated into a total solution that showed how all of the identified KPIÆs impact profit and quantified the dollar impact of all variations. The reporting solution that was put in place automatically creates prioritised lists of variances for the business to address. The second case study is a performance diagnostic project where driver trees were used to assess where gaps in performance were occurring, and then to evaluate the impacts of proposed initiatives.

Jan 1, 2007

By Lunardi P, Pelizza S

The link between the Lecco bypass and major road SS36 (Italy) requires the construction of a double two-way tunnel (through the mount San Martino carbonatic massif). The tunnel excavating section is about 90 sqm through mount San Martino carbonatic rocks. The mountain sides are unstable and are often the scene of large collapsing landslides (tens of thousand cubic metres). The tunnels are very close to the mountain sides. The use of blasting induces vibrations which may reach the Lecco built-up area. With a view to avoiding such dangers the excavating operations were carried out in two successive stages: - opening a pilot tunnel, whose section is about 10 square metres, by a full face TBM to eliminate the more intense vibrations which are generated by the first opening charges; - successive enlargement by blasting.

Jan 1, 1987

By P H. Warton

It is proposed to construct a gold extraction plant at Matatoki, near Thanes. Ore to be processed at the mill will come from reopened and enlarged underground mines north of Thanes. The project has been described in some detail in environmental impact reports (Worley Consultants Ltd 1984, 1987), and is now at an advanced stage in terms of obtaining the required statutory approvals.

Jan 1, 1987

In-seam drilling is conducted mainly to drain coal of gas and/or water prior to development or extraction. The requirements of inseam drilling for gas drainage have mainly surpassed the technical limits of rotary drilling and are mainly being addressed by guided down hole motor drilling, albeit at a higher cost. There is an increasing application of in-seam drilling to detect geological structures or other hazards or their absence in advance of mining to reduce the risks of underground mining. Close collaboration between miners, drillers, geologists, researchers and suppliers over the last four years has seen many advances made to improve the accuracy and reliability of inseam drilling. With such developments will come closer control over the ventilation and safety of future mining under deep gassy conditions, but not without costs. The paper summarises the current applications of inseam drilling, recent technological advances and the next generation survey and geophysical sensing tools which are currently being developed

Jan 1, 1998

The Bowen Basin coal field is an important energy resource. A relatively small proportion is avail- able by open cut operations. Responsible men throughout the world have warned of the need to increase coal research immediately. Because energy is still available in abundance these warnings have not been heeded in Australia. The characteristics of the Bowen Basin coal make it a fairly difficult underground mining proposition and a significant research effort is required to solve the problems likely to be encountered. Both industry and government have responsibilities in the economic recovery of the maximum proportion of the resource and jointly funded research administered by existing organisations should be inaugurated forthwith.

Jan 1, 1976

By K Ellis, K Quast, R Newell

The use of ammonia as a leaching agent in the recovery of copper from ores and concentrates has a number of potential benefits. These include the ability to treat ores with an acid consuming gangue, non-corrosivity, the insolubility of iron in the solution and increased selectivity. This paper reviews the previous and current use of ammonia based leaching systems for copper recovery and presents the results of a laboratory investigation that involved leaching of a copper concentrate and a low-grade ore. The effects of the operating variables (particle size, oxygen addition, agitation and temperature) are discussed. Of these, the particle size had the greatest effect, with decreasing size giving improved leaching rates and recoveries. The possibility of using ammonium salts in heap leaching is also discussed, and the results of some small-scale column leach tests presented. Possible methods for recovering the copper from the leach solution are outlined, and the types of ores and concentrates for which ammonia leaching may prove to be a viable alternative processing route are discussed.

Jan 1, 2000

By Shibata Y, Shimizu R, Fukushima A

Kobe is divided by the Rokko Mountains, runn- ing from east to west. The southern section of Kobe is highly developed in contrast with the northern section, but big, new residential pro- jects like the Hokusetsu New Town and Hokushin New Town are steadily being developed. To handle future traffic between the two sections of the city, the double-tracked Hokushin Line, now under construction, will connect the Shin Kobe Station of the Kobe Municipal Transit (Kobe's subway system) to the Tanigami Station of the Kobe Electric Railway. The locations of Kobe city and Hokushin Line are shown in Fig.-1 and Fig.-2 respectively.

Jan 1, 1987

The grades of alluvial ore deposits are low compared with grades of hard rock mining. This factor, combined with other parameters of irregular distribution of particles, bedrock irregularities, size of particles, nugget effect, ore characteristics, and wet horizons, combine to place alluvial deposits among the most difficult to evaluate, and on which to establish an ore reserve with a high degree of confidence. With increased geological input, correct selection and implementation of sampling method, due regard to sample representativity and process design, these confidence levels can be achieved.

Jan 1, 1987

Asbestos is a commercial term applied to fibrous varieties of several minerals, the properties of which are not generally appreciated by the majority of geologists. A thorough knowledge of these properties and of the uses of asbestos is of fundamental importance in the assessment of the economic value of an occurrence of asbestos. The varieties of asbestos that are used predominantly by the manufact- urers of asbestos products are chrysotile, crocidolite and amosite but chrysotile constitutes 95% of the world's usage. It is the properties of high tensile strength, 'heat resistance and large surface area that make chrysotile asbestos the most acceptable of the mineral fibres. There are no known exploration aids, other than direct visual inspec- tion of outcrops in ultrabasic environments, that could be used in the exploration of chrysotile asbestos. The surface exploration of an occurrence of chrysotile asbestos is relatively routine, though it lends itself to a unique form of bulk sampling by the use of a twelve inch diameter diamond drill core. The laboratory assessment of the prop- erties of the actual fibre requires specialized techniques and tests to assess not only the amount of fibre present but also its length distri- bution, inherent strength, filterability, dust content and other prop- erties. The way a fibre reacts to milling will determine what milling process- es must be implemented to ensure a product that is acceptable to the asbestos product manufacturing industry.

Jan 1, 1971

Future depth and production limitations of an ore hoisting system are fixed by its initial design criteria. There is little scope to extend these limitations once installation is completed. Depth and production rate upgrades from the initial duty to the hoistÆs practical limitations require capital expenditure in stages, each of which can be defined when assessing the initial system design criteria. A means of presenting and assessing the design criteria, the limiting factors in each option and the relative present and future capital costs is necessary to arrive at a solution that delivers the best value to the mine. Application of this technique to recent friction winder installations and upgrades in the Australian mining industry is of particular interest; however, the analysis methods are also applicable to drum hoists. It is usual to specify a minimum hoisting capacity and depth, based on mine ore handling design and production needs. The final hoist depth and production rate are usually a result of the initial hoist design and hence it is useful from the outset to specify a required production versus depth envelope for the mine. Technical solutions can then be modelled within this envelope at their initial and final duties and a comparative analysis made against the cost of installing and progressively upgrading each solution. Understanding the factors that constrain each solution to a maximum production rate at a given depth is important, as the costs of overcoming limiting parameters such as rope tread pressure and motor power can be significant. The task of understanding and evaluating the options open to the hoisting system designer is simplified using this approach. Communicating the results of a multi-dimensional problem such as hoist specification is also made easier using the graphical methods inherent in the analysis.

Jan 1, 2005

By P Cheluszka, M Jaszczuk, P Sobota

This paper refers to a new idea of stereometry of cutting drums of longwall shearers designed to get medium and hard to mine coals. A new way to place picks on a drum enables to readjust a number of picks being in contact with the body of coal to shearer haulage speed. Owing to this a remarkable increase in depth of a cut within the low range of haulage speed has been obtained. On comparing operating characteristics a considerable reduction in the specific energy consumption has been shown when using the units machined as per the new idea, in comparison with the units produced in series.

Jan 1, 2003

The Martha Mine is an open cut operation situated in the midst of Waihi town which has been operating since 1987. Since then it has produced some 700,000 ounces (oz) of gold and 4,000,000 oz of silver from an epithermal vein system. It was previously worked by underground methods from 1880 to 1952 to a depth of 600 m producing 5 million ounces (Moz) of gold and 30 Moz of silver. The licensed reserves are scheduled to be mined out early in the year 2001. An additional economic resource of over 750,000 oz of gold has been identified which can be accessed by deepening the pit a further 50 m along the main Martha vein. This would extend the mine life to the year 2007. Applications were lodged on 4 July 1997 for the necessary resource consents, discharge permits and variations for the current Mining Licence conditions. The extension project requires approval from the District Council, Regional Council and the Ministry of Commerce. The consent and permitting process is extensive because of the urban setting of the mine. An approach to keep the extension as similar as possible to the current operations was adopted to give the community and authority confidence in the proposed extension. This paper summarises the extension detail and the permitting requirements it has had to address despite the extension being "more of the same". The permitting process has been exhaustive with little recognition of the standards already achieved in protecting the environment which are recognised worldwide.

Jan 1, 1997