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By G T. Hefter, P Singh

The effect of using SO2 as an anodic depolariser in the electrowinning of copper from aqueous acid sulphate solutions has been studied using cells without/with a ceramic diaphragm. In all cases SO2-saturation of the electrolyte/anolyte decreased the anode potential by 68 to 75 per cent largely due to a change in the anode reaction from the oxidation of water to the oxidation of SO2 . However, poor quality deposits and low current efficiencies are encountered if SO2 is allowed free-access to the copper being deposited at the cathode. This situation is easily avoided by using a diaphragm to restrict SO2 to the anode compartment and for these conditions the resultant copper deposits are of a similar (high) quality to those obtained in the absence of SO2.

Jan 1, 1999

By Mallett CW, Rynn JMW, Hammond RH

Geological studies and satellite imagery of the Bowen Basin in Central Queensland, Northeastern Australia, have shown that the significant structural controls are a series of major North East/South West (NE/SW) trending structures, which can be traced as lineaments on Advanced Very High Resolution Radiometer (NOAA-AVHRR) imagery as well as on both Landsat Multi-Spectral Scanner (MSS) and Thematic Mapper (TM) imagery. These linea- ments can be traced offshore and into the Coral Sea by the distribution of offshore reefs and the bathymetery of the Queensland Shelf and the Queensland and Marion Plateaus. The seismic activity in Eastern Queensland seems to be divided into two distinct provinces separated by a seismically quiet area. This apparent seismically quiet area is bounded by two of the large lineaments seen on the satellite imagery. These features could be related to the deep crustal structure of Eastern Queensland and to the opening of the Coral Sea.

Jan 1, 1987

By R Valenta

Most developing projects face a range of technical and non-technical challenges, and examination of development histories can potentially provide insights into improved approaches to project development. The Kestanelik project in the Canakkale region of Western Turkey was acquired by Chesser Resources Ltd in 2008. Turkey is a significant and growing source of gold production, with sector participation by both domestic and international companies. While the broad ranges of challenges faced by developing projects is well known, there are relatively few case studies in which the range of technical, environmental, social and governance challenges are presented in a single contribution. Recent studies of undeveloped complex orebodies have particularly shown the extent to which environment, social and governance (ESG) complexities contribute to project delays and failures. The Kestanelik project faced a full range of technical and ESG complexities, and provides an illustrative example of the associated challenges. CITATION: Valenta, R, 2018. A case study of technical, social and environmental challenges for a gold project development in Western Turkey, in Proceedings Complex Orebodies Conference 2018, pp 73–74 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

McLeod: Without getting into the argument as to how well we can know our resource levels specifically in the immediate short term, I would like to make one or two points about the future, and perhaps try and persuade people that they are not really facing a doomsday. It is fair to say that over the last few years the rate at which we have increased our resources has far exceeded the rate at which we have used them, and this is likely to continue for quite a few years yet. As people are now looking for a substitute for petroleum, later on we will be looking for a substitute for coal, should the position get serious. After all man is pretty versatile, has plenty of initiative-and makes allowances for experience. It has been demonstrated here by the way people are looking at use of low quality coals and better use of the coals that are available. It would be fair to say that what now we regard as economically submarginal deposits will, by the time we need them, become economic. I think that there is quite a lot in front of us in exploration and finding new reserves. I would like to have comment from yourself sir, because I recall reading a report of a meeting, here in Wollongong I think it was, in which you addressed the local branch on the future of coal in Australia, and you said that the coal basins of Australia had been well explored and there was not much chance of new discoveries. Since that time we have seen some thousands of millions of tonnes turned up in the Galilee Basin of Queensland, we have seen five hundred million tonnes turned up in Lake Phillipson in South Australia. Do your previous comments still apply? I would like to hear from some of the exploration people, who are operating on an Australia-wide basis, as to how they regard our chances of discovering significant new deposits and significant extensions of known deposits. H,artnell: Mr. McLeod has asked me to comment on what he has just said. I think that the important thing is that our knowledge of the main coal basins in Eastern Australia is increasing in detail but for the most part the extent of coal basins is not being increased in respect of their superficial areas. There are additions but they are not substantially changing our expectation of what the main coal basins will be. I believe that our task is essentially to intensify our knowledge of the main coal basins that we know about. This is important for example for the various reasons that Mr. Roach was talking about, that is the problem of surface alienation, jeopardising the chance of recovery when you go to underground operations. My approach to this whole problem is predicated on the belief that coal has a special destiny to perform in the next fifty years. I believe that it is going to take up to fifty years and maybe a little longer before the enormously demanding technology for nuclear power recovery is in fact achieved. When it is achieved the supply of energy to the world will be enormous, much beyond what we have ever even dreamed about. The mind boggles at what the people of the middle of next century, of two thousand and fifty, will command in the way of physical resources. It is going to be, I believe, tremendous, but the technology involved is very demanding. I mentioned to Mr. McLeod the other day that according to the information that I got in November last, 60% of the nuclear power stations in the United States were out of action, by automatic cut offs because of safety requirements. The technology of breeder reactors seems each year to be a bit further off. In the meantime coal I am sure is going to be called on to supply power directly to fluidised bed and other technologies for power generation. It is going to be called upon in the near future, I believe, to supply liquid fuel on a vast scale and the only thing in my view that we should be thinking about is whether the coal producing countries of the world will succeed in producing as much coal as is going to be demanded. I believe the real challenge to the coal mining industries of the world is that they may fail to do what is going to be demanded of them. This is a challenge I believe to mining technology. I think that we should be working deliberately and energetically finding ways and means where underground recoveries, instead of averaging 50%, can average 50% plus, plus, plus, and this is the first requirement. We should be spending many millions every year, here and overseas, on increasing our means of winning coal because every tonne of coal that is alienated and left irrecoverable in the earth is going to weaken the capacity of the coal mining industry to fulfil, what I believe to be its destiny in the next 50 years.

Jan 1, 1975

By J Zhang, R Dimitrakopoulos

A two-stage stochastic mixed integer non-linear program is formulated for a mining complex to optimise strategic and tactical plans. The objective is to find the near optimal decisions for a mineral supply chain in the context with uncertainties in both ore supply and the commodity market (price and demand). The endogenous spot price in the commodity market and long-term sales contracts are considered in the formulation of the mining complex’s optimisation model and an ad hoc heuristic is developed to deal with the throughput – and head-grade-dependent recovery rate in processing plants. Numerical results indicate that the proposed heuristic is effective and efficient in numerical tests. Based on the proposed model and heuristic, a long-term contract design strategy is proposed for making decisions on the contract price and strategic investments. A shadow price based method is also proposed to evaluate the existing mining schedule.CITATION:Zhang, J and Dimitrakopoulos, R, 2014. Optimising a mineral supply chain under uncertainty with long-term sales contracts, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 25–32 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By Sano S, Ishikawa T, Nagaoka H, Hayashi Y, Hasegawa M

The stirred mill is regarded as one of the most efficient devices for micronising materials and has come to be actively used for preparation of fine particles. Recently, the demand for ultrafine particles was increased in many kinds of industries. In this paper, autogenous grinding to get submicron particles based on mutual friction feed material has been carried out using a stirred mill. The mill used was made of stainless steel and its volume was about 5.5 litres, and has 12 impeller blades. Sample used was limestone. In the present work, two operating parameters such as stirring speed and feed size of limestone were considered. The ground products were sieved in the size range from feed size to 325 mesh (45 lun), and from 45 to 0.17 pm the size distributions were measured by a laser diffraction and scattering method. The progress of grinding was evaluated by the increasing amount of submicron particles in products. As a result, the rotational speed of impeller with the minimum energy consumption to produce submicron particles was observed. It was found that the autogenous grinding with a stirred mill is an effective method for producing submicronized limestone.

Jan 1, 1993

Cretaceous volcanic activity (Hauterivian Albian) in the Peruvian Andes can be found along the coast of Peru and the western edge of the Andes mountains between 15o30'S and 5o30'S, extending discontinuously in south to Chile and north to Ecuador and Colombia. This volcanic activity formed in three aborted marginal basins; the NNW-trending volcanic Ca±ete and Huarmey, and NNE-trending Lancones basins. These volcanic rocks are predominantly andesitic and basaltic in composition, of calc-alkaline and tholeiite affinity with subordinate dacitic and rhyolitic rocks. One notable feature is the appearance of æocoitasÆ from Ica (14oS) south to Santiago de Chile. These rocks have a calc-alkaline to alkaline affinity. From south to north, the continental crust gradually becomes thinner, allowing mantle material to rise towards the surface. Ophiolitic sequences of this type form a marginal basin in Colombia. Very low-grade regional metamorphism which affects the volcanic rocks also varies gradually from south to north. Between Santiago de Chile and Ica this takes the form of burial metamorphism, with moderate geothermal gradients (20o-30oC/km). Metamorphism in the Huarmey basin is transitional between burial and ocean-floor metamorphism, with very high geothermal gradients (>3000C/km). High geothermal gradients are also apparent in metamorphism of the Lancones basin, though less than the other basins. Ocean-floor metamorphism is present in the ophiolitic sequence in Colombia. Associated mineral deposits in the Huarmey and Lancones basins, and in the north, are of the volcanic massive sulphide-type (VMS). The principal deposits in Peru are Leonila Graciela (20 Mt Zn and Pb) and Tambogrande (40 Mt Cu and Zn). There are also smaller mines and prospects. To the south of Lima, manto-type Cu deposits (CuMT) are found with a mineralogy of chalcopyrites, pyrites, magnetite, actinolite and apatite. The main example is Raul Condestable (10 Mt Cu). Other prospects are present to the south and Chile has some very large mines of this type (El Soldado, Lo Aguirre). The notable differences between the CuMT and the VSM deposits are thought to be the result of the prevailing conditions in the earthÆs crust during the Hauterivian Albian. To the south, calc-alkaline and alkaline volcanic activity in aborted marginal basins, with thicker crust, was thick, produced moderate geothermal gradients associated with burial-type regional metamorphism and deposits of CuMT. In the north aborted marginal basins associated with calc-alkaline to tholeiitic volcanic activity and a gradually thinning crust, produced transitional regional metamorphism between burial-type and ocean-floor type, associated with high to very high geothermal gradients and VMS deposits. In Colombia these conditions led to ophiolite extrusive rocks, ocean-floor metamorphism and also VMS deposits.

Jan 1, 1999

By R G. Reddy

The complexity in treating environmentally harmful impurities such as As, Sb, Bi from the base metal matte or metal in the smelting stage are responsible for the high cost of the refining process. The impurity capacities (such as arsenic, antimony and bismuth) of slags were calculated a priori using Reddy-Blander (RB) model. The capacity predictions were for a wide range of matte and slag compositions in copper smelting conditions. The calculated impurities capacities and impurity distribution ratios results are in good agreement with the available experimental and industrial slags data. The a priori knowledge of impurities is useful for reduction of energy consumption and enhanced environmental control in the current and future non-ferrous metal processes.

Aug 21, 2024

By Riley S. J

The basic aim of mine planning is to design mine layouts and schedules that achieve optimisation of operations, minimum cost and maximum resource recovery. Successful accomplishment of this aim is facilitated by timely and comprehensive rehabilitation planning commencing at the pre-feasibility stage and continuing until the end of mining. Incorporation of a final landfomt design for waste rock dumps in a mine plan requires a prediction of surface stability, which may be achieved through erosion modelling. Erosion prediction models can be placed in two broad categories: soil loss prediction models eg USLE and CREAMS, and geomorphic models such as SIBERIA. A waste rock dump landform design based on selected slope form and grade and drainage systems should be developed as part of planning. A digital terrain model (DTM) of the landfonn should then be produced which can be modelled for long-term erosional stability using pre-determined parameter values. If acceptable standards of stability are not achieved, the landform should be redesigned and remodelled until the desired result is obtained. The planning process incorporating models requires knowledge of spoil or waste rock properties and model parameter values. This information is site specific and can be obtained from drill cores or costeans at the pre-mining stage and from spoil or waste rock during the mining stage. Realistic model parameter values are critical in post-mining landfonn design and can be obtained by several methods, including rainfall simulation, monitoring, geochemical analyses and grain size analysis.

Jan 1, 1994

By C W. Lu, Y F. Chen, M J. Lian, W W. Guo

This paper proposes a set of new approaches for the optimisation of planning and designs in mines by means of evolutionary algorithms, which include the determination of ore grade, layout of development system, selection of mining methods and production scheduling in underground mines. The applications indicate that evolutionary algorithms are particularly suitable to the complex and complicated problems in mines.

Jan 1, 2003

In recent years, the. art of electric steelmaking has received a great deal of attention, and naturally, much controversy has existed from time to time regarding the relative merits of different practices and tywes of furnaces. Nevertheless, at the present time, the basic principles of the process are reasonably well established, and by far the greatest percentage of electric steel is a product of the basic lined, direct arc type furnace. Ferro alloy manufacture has demanded the development of furnaces having very different characteristics to those used for steel. Some special alloys, however, require conditions of manufacture which are more closely approached in the steel type furnace, and thus the latter has been adapted where necessary for the production of these alloys.One such alloy, low carbon ferro-manganese, is manufactured at Whyalla, South Australia, in a basic-lined, direct arc furnace, which is used alternatively for the production of alloy steels.BRIEF HISTORY OF THE ELECTRIC FURNACEThe principle of melting by electricity was first applied to the melting of iron in 1879 by William von Siemens, whose equipment consisted of a small crucible into which were introduced two carbon electrodes. Very little practical development took place in the next 20 years, although in 1890 a Frenchman named Heroult designed a direct arc furnace for the production of ferro alloys. At the beginning of the 20th century, several types of furnaces were patented for steel melting, the most important of these being the Heroult, using a direct arc, the...

Jan 1, 1951

The history of the discovery and development of the Kambalda nickel orebody. is reviewed and the decision to process the Kambalda concentrates by the Sherritt-Gordon process at Kwinana is discussed. The Kwinana Nickel Refinery is described and the problems encountered in the first year of operation are Outlined.

Jan 1, 1971

By R Badreddine, J Rose, L De Windt, P Chaurand, L Raimbault

Municipal solid waste of incineration (MSWI) bottom ashes are recycled as aggregates in civil engineering. These heterogeneous materials are composed of crystalline and glassy solid phases which contain trace metals, presenting a potential risk to the environment. Secondary ion mass spectrometry (SIMS) can provide quantitative chemical information, in particular the localisation of metals at trace level. Unstable glassy phases formed during incineration are present in relatively high proportions. Their analyses suggest a continuum between melilite-bearing glasses and dark glasses enriched in iron with abundant spinel aggregates. These primary glasses are enriched in zinc (~4500 ppm) but depleted in lead (~800 ppm) by comparison with the bulk chemical composition and reference materials. Heterogeneous cementing and encrusting admixtures on coarse grains are studied in a second step. SIMS imaging suggests a superposition of band zones including an intermediate layer enriched in iron oxyhydroxides and a superficial layer with calcium accumulation. A strong spatial association between lead and iron is systematically observed. Extended X-ray absorption fine structure (EXAFS) supports these observations by demonstrating that lead co-precipitation within iron oxyhydroxides, or sorption on their surfaces, may be a main containment process in the cementing and encrusting admixtures, whereas lead speciation is globally more complex in MSWI bottom ash.

Jan 1, 2008

THE plant is one of the usual type of Mond plants, and contains no new features worthy of comment. A brief description of the process, however, with a few remarks on the working of the plant, may prove of interest.Producer gas is made by passing a mixture of air and steam through incandescent carbon contained in a furnace called a producer, which, in the Mond type, is a cylindrical casing of steel plate, lined with firebrick, and fitted at the lower end with sloping fire-bars'. Coal crushed to an even size (about 2-in. gauge) is elevated to bunkers over the producers, from which it is fed into a measuring hopper on each producer.The hopper is a cast-iron cylinder fitted with a swing cover at the top and a bell valve at the bottom, worked by a lever and balance weight. When a charge of coal is run from the bunker into the hopper, the cover is closed, and the bell valve is lowered, allowing the coal contents to drop into the producer. Thus no gas can escape from, or air be admitted to, the producer during the process of charging. The hopper discharges its coal through a steel pipe-shaped container called the bell, which projects about 9 in. through the roof of the producer. The function of the bell is to spread the coal evenly over the fire, and supply coal to any portion of the fire as it settles.

Jan 1, 1918

The appearance of the Cornish miner in South Australia was, in the simplest terms, the result of resource development economics. In Cornwall in the middle of the 19th century tin and copper mining was declining, while in the new colony of South Australia copper mining was booming. Experienced hard rock miners in Cornwall there- fore escaped unemployment at home by accepting an assisted passage to South Australia. There, in a colony where they were needed, they made their skills available and received good wages. There are many testimonies which support this simple thesis. Take for example the following extracts from contemporary newspapers in Corn- wall: Persons of small capital will find this an excellent opportunity for emigrating to the young and thriving colony ... The miner will find a rich and unbroken field for his operations. The Colony abounds with minerals... (West Briton, 19 July 1844) Miners make a great deal of money here (South Australia). All of them earn ú2 to ú3 per week and in many cases when they have a portion of the mine on tribute one person has cleared ú100 in a couple of months or so. (Cornwall Royal Gazette, 21 July 1848)

Jan 1, 1987

Stressed steel cables, similar to those used in pre-stressed concrete, have been used for rock mass reinforcement, in civil engineering, for many years. This type of reinforcement has been attempted for open pit wall support, on several occasions, but has never gained wide acceptance as a practical approach because of high cost and complexity of installation in a mining environment. On the other hand, untensioned, fully grouted cable dowels (cable bolts) have gained wide acceptance for ground support in underground mining and it is perhaps surprising that this technique has not been used to a greater degree in open pit mining. The first systematic application of this technique in Australia was at the Mary Kathleen uranium mine in 1976, where it was spectacularly successful in maintaining steep stable walls in a jointed rock mass with unfavourably dipping structures. Cable bolting, and other techniques, are now being used to an increasing degree for wall support in both small and large open pits, for two basic applications: 1. stabilisation of potentially unstable sections of a wall, or 2. to allow steeper walls and reduce waste stripping volumes. In virtually every situation, wall rein- forcement has significant economic as well as technical advantages. The paper describes the development of the techniques, the mechanisms of wall support, the methods used, and discusses several case histories of its application to Australian open pit mines.

Jan 1, 1986

By Gillies A. D S

Replies to a comprehensive questionnaire on mine water resource management systems (WRMS), which were distributed to a selection of Australian mining operations in 1991, are analysed. Although the replies cannot be considered fully representative of the industry, they do provide a good qualitative indication of water resource management in the industry at that time.Within Australia's largely arid land mass, a majority of mines nonnally need to conserve water, a few need to dispose of water and a number face a seasonally varying position. An assessment of the importance of WRMS compared with management of ore extraction and processing is given. A risk assessment of failure is given; there is more acceptance of WRMS failure in the mine compared with the mill. An assessment is made of considerations in WRMS design. Managements are generally pro-active in the design of WRMS and in the setting of perfonnance standards. The operational characteristics of mine systems are examined in detail.Companies generally do not appear to allocate sufficient resources for the collection of basic WRMS monitoring data and knowledge of the water budget to efficiently manage the system. This indicates scope for considerable cost savings in most mines.

Jan 1, 1995

By Skinner A. J, Thoman B. C

The general structure of microprocessors and their method of use is described, and de- tails given of their application in two parti- cular examples of instrumentation for mineral concentrators. One is in a pulp density gauge, and using this example, the way in which a microprocessor-based unit can be made to be self-calibrating is described. The other is in an on-stream analysis detector for uranium in solvent, where a microprocessor is used to re- place a mini-computer.

Jan 1, 1977

By Tarrant GC

Cement and resin encapsulated tendons are widely used in the stabilisation of mine roadways. One of the main factors in controlling the efficiency of the reinforcement is the ability of the tendon to generate load in response to rock deformation. The analysis of field data from instrumented reinforcing tendons complimented with extensive laboratory investigations have more accurately defined the mechanisms by which load generation occurs. The role of reinforcing tendon profiles, hole geometry and encapsulation medium properties in controlling the reinforcement stiffness and capacity are discussed. The results of the investigation have implications in both the design of rock reinforcing systems and the optimisation of encapsulation mediums and tendons.

Jan 1, 1992

Most of the gold reef mined today in South Africa is approximately 1 m in width with slopes about 30 m long. To prevent production interruptions it is essential that the stopes should not be blasted in sections. The shortage of experienced labour and arduous working conditions at the face dictate the need for simple blasting techniques.Hence, a pyrotechnic blasting system of sequential firing is in use at present, although research work to improve this technique is in progress.

Jan 1, 1985