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A relationship is predicted between oxidic nickel in slag, oxygen in matte and Ni/Fe ratio in matte after the examination of thirty sets of contiguous matte and slag samples taken from industrial nickel smelters. Oxidic nickel in slag is found to increase with increase in oxygen content of matte of constant Ni/Fe ratio, and it is proposed that the relationship may be used to predict nickel solubility in slag from a knowledge of matte composition alone.

Jan 1, 1979

By Lawson F

A rotating disc geometry has been used to provide a uniformly accessible surface for a kinetic study of the cementation of the metals cadmium, lead and silver from dilute aqueous solutions. This work is an extension of studies carried out on the Cu/Zn and Cu/Fe systems for which the rection rate was found to be completely solution-phase mass-transfer controlled. When the amount of material deposited was greater than 0.2 to 0.4 mg/cm2 there was an apparent enhancement in e which is attributed to the formation of a roughened deposit. This same phenomeon was obseived in the Cu/Zn Cu/Fe systems. Again, the rate of reaction of each system investigated was found to be solution-phase mass ,..~sfer controlled.

Jan 1, 1970

By Fiedler VA, Threadingham GM, Leckenby DF, Clarkson CJ

The Utah Development Company Research and Development Laboratory has embarked upon a programme of optimisation of the company's coal preparation plants. This goal is being accomplished in a three-fold manner - use of pilot plant equipment for optimisation and modelling of the various unit operations, evaluation or development of on-stream ash analysis for process control, and evaluation or development of alternative processes. In each of these areas, digital data acquisition- and at a later stage, process control feedback, is being extensively utilised, based largely upon the use of the HP85 and HP9915 desktop computers. A variety of input/output configurations such as HPIB, BCD, GPIO are used, and at times supplemented by microprocessors such as the Intel 80/05 to assist in data transfer. This paper will discuss a number of specific projects, especially in relation to the manner in which the variables are monitored, and the data later retrieved and analysed.

Jan 1, 1983

It is a privilege for me to participate in this vitally important discussion of The Role of Governments in the Management of Resources. The distinction of my fellow participants is evidence that this event is a matter of extreme importance and attracts international attention. In the management of natural resources, government and private enterprise share awesome responsibilities for the economic well-being of nations. Mining and its relation to the prosperity of nations is almost as old as recorded history. Copper was being mined and extractive metal- lurgy practised at Timna in Israel's southern desert as far back as 4000 B.C., and the rich mines of Laurium not only saved the Greeks from Persian domination 2500 years ago, but also provided Athens with a monopoly of silver in the Mediterranean world. This bolstered the economic power of Athens and led to the golden age of Greek commerce and culture.

Jan 1, 1978

By C Czerny, T Elkington, L Lorenzen

The Dutwa Nickel Project is a nickel laterite atmospheric leach project located in Tanzania that has been under development by African Eagle Resources plc (2012). A bankable feasibility study (BFS) has been progressed to evaluate mining of the resource (107 Mt at 0.92 per cent Ni) followed by hydrometallurgical processing on-site to make a mixed nickel-cobalt intermediate product. The unique relatively high silica contents in the Dutwa deposits, as opposed to limonite, which is more commonly occurring in nickel laterites, presented the possibility for beneficiation of the ores to enhance the leach feed nickel grades and provide economic benefits in terms of operating and capital cost efficiencies.Geometallurgical relationships, based on the results of an extensive variability metallurgical test work program for beneficiation and leaching, were developed for the BFS, which resulted in an improved understanding of ore classifications within the deposit and their responses. The geometallurgical information obtained has been instrumental in making key preliminary techno-economic decisions, such as forecasting whether or not mined material should be beneficiated and was ultimately used to drive the mine plan towards the prioritisation of areas within the deposits that delivered the best cost efficiencies and overall project economic outcomes.CITATION:Elkington, T, Lorenzen, L and Czerny, C, 2013. The use of geometallurgical relationships in process route selection and mine plan optimisation for the Dutwa Nickel Project, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 207-216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By Johnson G. D

The typical management systems used to address the issue of operating risk centre around technologies that identify, analyse and evaluate the risk factors. These logical systems such as HAZOPs, Fault Tree Analyses, etc rely heavily on technical considerations and process flow analysis. However, several research projects, across industries and countries have clearly shown that up to 80 per cent `operating risk' is determined by the actions of workers, supervisors and managers. Yet, most of the focus of risk management is on technical and procedural issues. This suggests that a significant imbalance exists in our management systems and that industries are unlikely to show significant improvement on current levels of safety performance. Effective risk management must include the intangible element of the organisation psychology towards risk. A practical and theoretically sound approach had been researched and developed in and for the mining industry. This paper describes the approach and methodologies applied at the Cosmo Howley Gold Mine in the Northern Territory, where an inclusive approach to managing financial and operating risk was followed. The Cosmo Howley Mine showed a dramatic reduction in lost time injuries and improvements in financial indices - providing conclusive evidence of the link between management effectiveness, safety and productivity. This `triangle' has often been the subject of speculation and theory. It is demonstrated in this paper how the management team of Cosmo Howley focused their practices and systems on the improvement of organisational dynamics, ensured tangible and clear focus on parameters of costs and safety and how the improvement process was managed. It is concluded that the improvement process did not require a `major re-engineering' of the organisation. The organisation culture changes that occurred were incremental, planned and effective. It entailed the implementation of sound risk management methodologies, and ensured that a significant emphasis was placed on an aspect that is defined as `organisational dynamics'.

Jan 1, 1994

By Demin SS

Slow seismotectonic movements along the in-clined deep fault zone under the compressional horizontal stresses are supposed to be the prin-cipal mechanism controlling the structure and processes in the active ocean margins. Within the scope of the plane strain problem a simple 2-D geomechanical model for the evolution of an island arc system is investigated. We consider a homogeneous elastic half-plane with a shea-ring surface crack. The key element of the model is viscous interaction between the crack sides, the viscisity varying with depth. The model dif-fers from the classical steady-state mode of subduction by nonstationary creep processes on deep faults and by possibly cyclical development of the transition zone.A numerical modeling of the stress-strain state within the island arc system through time was carried out using a semianalytical approach. The results of simulation are in good agreement with geological, geophysical, and seismological data.

Jan 1, 1990

RME has a vision for a new grinding plant operational paradigm made possible by RMEÆs fast, safe Mill Relining System. Some new liner designs can degrade SAG mill performance because of mill volume loss, ball strike (rotational speed limitations) and other issues often brought about by modifying liner design for maximum life and without a backward glance at metallurgical consequences. Freshly relined mills can initially produce as little as 80 per cent of their maximum throughput, that maximum occurring toward the end of the linersÆ wear life. RMEÆs proposition is to see new liners designed for maximum commercial performance. This may mean more frequent mill relines but with liners designed to yield optimum grinding, metallurgical and profitability performance, not maximum life. In other words, mill liner profiles and mill relining speed become key operational controls and not simply æmust doÆ maintenance functions. Taken to the extreme, liner profiles may prove capable of ætuningÆ a grinding plant for maximum profitability in any metal price environment. Following the introduction, the first section of this paper provides an update describing recent and significant developments within RMEÆs range of Mill Relining Systems, the enabling technologies which permit more frequent liner exchange without incurring additional downtime imposts. The second section outlines RMEÆs vision of a æliner profile versus profitabilityÆ commercial model, developed either intuitively or by using a combination of new measurement and modelling technologies. These new measurement and modelling tools provide the opportunity to predict the optimum commercial outcome, off-line in the virtual world, before committing to an expensive liner experiment.

Jan 1, 2007

By Slater R

The initial planning and detail design phase leading to the development of a 7.5 m internal shaft to service the deep 3000 and 3500 copper orebodies at Mount Isa, Queensland is well advanced. The choice of internal shaft access was made over alternative methods such as a decline from existing levels and borehole hoisting. The resulting access development requirements and shaft configuration for production have been determined. Several techniques are being studied for shaft development. These include the application of blind shaft drilling and large hole reaming methods as well as conventional sinking techniques. As the 3000/3500 Orebodies extend from 1000 metres to more than 1800 metres below the surface, high stress conditions and ground temperatures ranging from 45CC to 62CC are anticipated. The effect of these on the methods being investigated to create a favourable working environment will influence the final choice. Exploration diamond drilling is in progress to confirm the geology of the orebodies so that planning for their extraction including refrigerated ventilation concepts can proceed.

Jan 1, 1982

By Alwan M

At Binebase mineralisation is hosted within an andesitic Neogene volcaniclastic succession on Sangihe Island, Indonesia. Two major alteration types occur; an initial widespread phyllic assemblage of quartz -illite with chlorite, smectite, gypsum and pyrite, and a superimposed quartz - barite - sulphide assemblage. The phyllic alteration arose from a neutral to weakly acidic hydrothermal solution of greater than 200 degrees C, and the quartz - barite - sulphide assemblage arose from a cooler slightly more acidic fluid. This second alteration event is interpreted to have selectively replaced permeable volcaniclastic breccias and coarse lithic tuffs within the altered sequence. Gold and silver mineralisation is associated with the latter alteration, and is locally controlled by the degree of silicification and sulphide abundance. The sulphides present are pyrite, covellite and chalcopyrite. The sulphides are very fine grained with colloform and framboidal textures and were deposited contemporaneously with the bulk silicification of the coarse sediments. A large portion of the mineralised rock has been oxidised to a quartz - barite -limonite - goethite - jarosite assemblage.Coincident gold, silver and antimony geochemical soil anomalies gave the best correlation with anomalous gold and silver grades in bedrock as identified by drilling. Resistivity proved a reliable geophysical method for delineating zones of silicification.

Jan 1, 1990

By Dennis B

The Hilton Mine, 20 km north of Mount Isa was discovered in 1947. The underground mine has been a significant producer from 1989. The long development history is the result of complex orebody geometry, difficult metallurgy, dewatering problems and competition for development funds from the then expanding Isa Mine at Mount Isa. At present it produces 1.4 million tonnes annually. Its 21 million tonnes of reserves are necessary to supplement Isa Mine production.Hilton Mine is located in the Urquhart Shale formation of the Mount Isa Group, within the Mid Proterozoic Mount Isa Inlier. The seven developed orebodies have suffered strong structural deformation. Each orebody has a unique mixture of mineralogy and texture which effects ore value and metallurgical performance. These characteristics have proven useful for correlation purposes.The faulting and folding have caused difficulties with orebody interpretation, geomechanical complexities and has influenced the choice of mining methods: Initial cut and fill and open scope designs have given way to bench mining methods in response to better understanding of the eedloav and economic constraints.

Jan 1, 1993

Up to 80 per cent of the copper in a bornite ore can be quickly leached with percolating acidified ferric sulphate solutions. The upper limit for rapid copper extraction is set by the conversion of bornite to slowly dissolving chalcopyrite. The dissolution occurs in two stages: a rapid linear initial stage, followed by a slow, non-linear stage. The initial step is largely controlled by the rate of oxidant supply (Fe2(S04)3); temperature is not an important variable during the initial reaction. The second leaching stage is controlled by chemical and physical factors and is temperature dependent. The initial copper leaching rates are insensitive to both the concentration of the ferrous sulphate reaction product, and the sulphuric acid concentration.

Jan 1, 1973

The Mt Newman Beneficiation Plant uses a combination of heavy media deans, heavy medium cyclones and Reichert cones to produce saleable iron ore concentrates from low grade iron ores. The aim of this paper is to discuss score of the changes that have been made to improve the operation of the heavy medium circuits.

Jan 1, 1987

By Grant J

In surface mining, significant improvements in efficiency can be obtained through greater control over the formation of the muckpile. By tailoring the muckpile shape and its looseness to the requirements of the excavating equipment savings can be rea- lised through increased production, machine life and reduced maintenance. For instance, one open cut coal mine has recently estimated that a 2001o improvement in its front row throw would realise $320,000/year savings in rehandle costs alone. Previously greater throw has been achieved by increasing the powder factor through increased quantity of explosive or by drill- ing a larger number of holes-both at a significant cost penalty. However a recent series of experimental blasts demonstrated that it was possible to achieve a twofold increase in the distance of throw of a single row blast by simply changing delay timing alone. The Nobel Electronic Delay Detonator was used to provide the timing flexibility and control required for a thorough study of the effect of blast timing on heave. Whilst it is well accepted that the front row of a blast dominates the extent of throw, it was also found that the profile of the blast could be significantly altered. To date, the general consensus has been that the muckpile for- mation from a blast is a function of the blast geometry, the rock type, the explosive and the initiation sequence. Typically the geometry, rock type and initiation system have a far greater impact than the explosive type. This has been demonstrated by many high speed film studies. However the extent of influence via initiation has rarely been fully evaluated, owing largely to the limited control offered by conventional detonators.

Jan 1, 1988

By D A. Sims

This paper outlines the contributing factors to a series of erroneous Mineral Resource estimates which led to considerable loss, including significant reduction of mine life and consequently a large write-down of asset value. The error prompted divestment of the mineral asset in the short-term by the owners, a major mining company. There were multiple and complex contributions to the result: • The mine was undergoing a transition in the deposit geology with increasing depth that was not accommodated in the models. Early indications of the geological transition in initial drilling were generally unrecognised in resource modelling. The shortcomings of the models became apparent with increasing infill drilling and subsequent production reconciliation. • There was a lack of recognition of, and confidence in, site-based input and skills by corporate technical management. The site had a reputation internally for over-delivery to plan early in its life and that supported the anticipation of ongoing metal delivery into the mine plan by management. • A corporate lack of confidence in site being able to adequately domain the mineralisation led to the use of a CIK domaining process, rather than one which was geologically based. This domaining process led to gross over-statement of mineralisation trends reflected in the subsequent OK estimate. • Timelines on the outsourced estimation process were so short that validation was not possible. Obvious errors in the estimate versus data were not able to be used to correct the issues and the site’s Competent Person sign-off occurred without adequate checks. This case study is presented to reinforce the concept that Mineral Resource estimates are not solely based on the ability of the Competent Person to satisfactorily guide the process. There are usually multiple complex issues in the estimation process which need to be recognised and considered in judging reconciliations of model to actual.

May 24, 2023

The C.S.A. copper lead zinc mine, located seven miles north of Cobar in Central Western New South Wales, is the largest known mineral occurrence in the Cobar Mining Field. Hosted by the steeply west dipping, west facing sediments of the Cobar Group, the generally discordant orebodies occur within a strike width of 600 ft and an overall strike length of 1200 ft. They comprise lenticular steeply north pitching and east dipping zones of sulphide mineralisation which range in composition from massive pyrite-sphalerite-pyrrhotite--galena to less massive pyrite- pyrrhotite-chalcopyrite varieties. The thinly bedded siltstones, shales and graywackes hosting the mineralisation appear to have derived many of their constituents from volcanic sourcesä They have been metamorphosed to the greenschist facies of regional metamorphism. At least two stages of deformation and folding have occurred. The first stage folded the rocks on a south pitching fold axis into their present configuration, and super- imposed a strong axial plane cleavage which subsequently guided the emplacement of the mineralisation. The second stage of deformation is considered to have controlled the zonal distrib- ution of the orebodies and the appropriate fold axis appears to coincide with the long axis of the orebodies.

Jan 1, 1969

This paper is written as a supplement to that of Edwards, Baker and Knight on "The Geology of the Wonthaggi Coalfield" 1, the West Area pit being in an early developmental stage at the time of their paper. The thin seams to the west of Dudley Basin 2 had beenknown for many years but it was not until 1935 that it became necessary to work them. The West Area Pit came into production as Dudley Area Pit approached exhaustion in 1937. From available information it was estimated that early work would be in a 36in. bottom seam. The present top seam was not included in the reserves, but it was to be extracted where it proved thick enough for economical working.THE SEAMSEdwards, Baker and :Knight (1944) had insufficient information to correlate positively the West Area seams with those in the Dudley Basin. Their opinion was, however, that they were a westerly extension of the Bottom Seam. Since then the driving of the present north-east heading towards No. 4 Bench McBride Tunnel has established that the West Area seams are those worked as Bottom Seam in the Dudley Basin. West Area Top Seam is a seam that occurred above the Bottom Seam in the Dudley Basin. Only sporadic attempts have been made to work it in Central Area, because 30in. was considered an economic minimum height until recent times. This seam should not be confused with Top Seam, Dudley Basin, which lies some 300ft. above the bottom seam measures and except in isolated areas over deeper workings has been eroded away in West Area.

Jan 1, 1953

This paper concerns a pragmatic approach to a problem that is common to many operations in the mining industry: how, over the short-term, to grasp the extent and distribution of long-term financial risk from environmental causes and reduce these risks strategically, in order to maintain stability and flexibility in the operations. Surprisingly, many companies operate without an environmental master plan or tools that can help managers measure and reduce financial risks. Such companies may be subject to unknown unacceptable financial risks from environmental causes. While many companies have some kind of internal system of environmental standards, it is often the case that such systems have uneven or limited effect, and offer no opportunities for visualising, measuring or managing aggregate financial risks from environmental causes. `Aggregate risks' are defined here as the calculated total expected financial costs to a company, or a subdivision of a company, from environmental causes at nominated operations over a defined time period. Aggregate risks take into account the type and magnitude of an environmental problem set, the likelihood of occurrence, and the time frame during which the problems will develop or solutions are required. For the large corporation, the 'amount of' aggregate environmental risk is a statistic that can be managed, along with other financial parameters, at the corporate level to improve the stability and predictability of operations, and protect the interests of shareholders. This paper concerns development of a management framework and a tool for the large corporation that responds to the need for managing aggregate environmental financial risks. The logical framework proposed to overcome the need for strategic vision is the Environmental Master Plan, and this is described in the next section. The analytical tool proposed to measure aggregate risks and provide relevant data and insights to managers, is called an Environmental Risk Management Information System, and its mechanics are described in a subsequent section.

Jan 1, 1994

By Okabe K

Development in the theory and practice of hearth drainage is reviewed. Difficulties in the hearth drainage were re- newed during late sixties and early seventies when the size of a blast furnace and the top pressure were increased to result in the increase in tapping rate. Hearth drainage was improved first by in- creased number of tapping and then decreased tapping rate as it was predicted by theoretical studies. State of the coke bed in the hearth, e.g., 'floating' or 'sitting-on' the hearth bottom, is discussed in relation with influential factors on it and its influence on the furnace operation. The 'sitting-on' coke bed is to be aimed at for the consistent furnace working and for the lower rate of erosion of the hearth refractory. As the continuous tapping became standard prac- tice in large blast furnaces, the interest in the basic research renewed. Prospect of the further research including mathematical modelling of the hearth drainage is discussed.

Jan 1, 1981

By M Bettison, R Wright, N Taylor

The primary mine planning focus during early study phases of future mining projects is Life of Asset ore production and grade quality, this will always be the situation. While waste schedule optimisation is generally considered in the latter study phases nearing execution for a limited number of schedule periods only and not a true optimisation considering all attributes such as waste destination location, design, cycle time and closure. This can be particularly applicable in large multi-pit bulk mining operations where one approach to meet Life of Asset ore tonnes and grade targets has been to maintain pit development flexibility resulting in large open pit areas and substantial expit Overburden Storage Area (OSA). The value opportunity is to develop a Life of Asset waste schedule source-to-destination optimisation prior to mine development considering all applicable attributes and routinely review throughout the Life of Asset taking account of improved ore and waste knowledge.CITATION:Taylor, N, Wright, R and Bettison, M, 2018. Utilising mine planning to deliver closure landforms through productive movement, in Proceedings Life-of-Mine 2018, pp 96–99 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018