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Cannington is a Broken Hill type deposit discovered by BHP Minerals, now BHP Billiton, in 1990. The deposit is located south east of Cloncurry, Queensland, Australia. The deposit occurs in the Eastern succession of the Mount Isa Inlier within the Soldiers Cap Group. The mineralisation is interpreted to be confined to two limbs of a synform wrapped around a core amphibolite. The silver, lead and zinc mineralisation is zoned within silicic and mafic units. There is a strong association between silver and lead. The combination of mafic and silicic zoning, differing relative grades of silver, lead, zinc and iron, the relative position of the mineralisation on the synform limbs and differing metallurgical performances have resulted in the identification of ten different ore types, four of which are currently extracted. Ordinary Kriging (OK) is used as the resource estimation methodology for the silver, lead and zinc mineralisation. This modelling approach has performed quite well for resource reporting and long term mine planning. However the limitations of this modelling technique to adequately provide information on a local stope scale has lead to the geological staff to consider alternatives to this approach. Limitations of the current modelling method apply to both the geometry of the orebodies and the grade variability. Since early-2000 the Cannington geologists have been experimenting with modelling both the distribution of the mineralisation types using Probability Field conditional simulation (PF) and the distribution of grade using Sequential Gaussian Simulation (SGS). This approach to local modelling of mineralisation type and metal grades using conditional simulation (CS) has undergone a full evaluation by comparing grades estimated for stopes using both the (OK) resource model and conditional simulation (CS) models. The mine planning staff have used the CS derived models, and have found improvements in grade predictions over the currently utilised Ordinary Kriging û derived resource model.

Jan 1, 2003

By Newman H. A

Goldsworthy Mining Limited is currently mining iron ore at an annual rate of 7 million tons from several small orebodies, each of which exhibit wide variations in iron, phosphorus, silica and alumina contents. Each orebody is mined at its average ore reserve grade and therefore mine planning and grade control techniques have had to be tailored to achieve a constant production blend.

Jan 1, 1973

An Environmental Impact Statement (EIS) for a major mining development typically has to address various aspects of surface water management, including some which generally tend to be the more contentious: the diversion of rivers and creeks from areas disturbed by mining, and their rehabilitation; the effective management of disturbed area run-off via the collection, containment and treatment of contaminated water on site in sedimentation dams; the collection, containment and treatment of mine pit water; the decommissioning of surface water storages; final void water quality; and water discharge criteria. Environmental Impact Assessment processes for proposed mining developments in Australia at the state and commonwealth level usually involve a form of Initial Advice Statement (or Notice of Intent), Terms of Reference, an EIS, and a Supplementary Report (or similar) which responds to agency and public comment on the EIS. The EIS is used by approval agencies to decide the acceptability of the Project, and to set the conditions of approval. The conditions are often in the form of a state-issued æOperational LicenceÆ or similar. With mining, the initial approval at the EIS stage is often just a pre-cursor to various other planning related approvals, including obtaining a mining lease. Afterwards, mine plans and plans of operations must be submitted to government at various stages of the mineÆs life, ostensibly to provide the detailed mine planning over periods of one û five years. Despite all this additional planning and documentation beyond the submission of the EIS, government approval agencies are increasingly not satisfied with conceptual water management designs and commitments to an outcome (such as meeting a specified water quality standard) in the EIS. Agencies are also requiring sufficient water management design information to be convinced that the outcomes are achievable. To assist proponents of major mining developments, the Queensland Government has published Technical Guidelines for water management, and Environment Australia has published a æBest Practice Environmental Management in MiningÆ booklet on water management. In addition, the Australian and New Zealand Environment and Conservation Council (ANZECC. 2000) has published Water Quality Guidelines which provide an approach to water management, and provide receiving water investigation trigger criteria. So, what are the water management issues that are likely to be the subject of comment, debate and negotiation prior to the EIS being approved? and what commitments may a mining proponent have to make in order to convince the approval agencies that sufficient investigation and design has been provided? This paper provides some answers to this question, by reference to recent major mining proposals which the author has managed through state and commonwealth Environmental Impact Assessment processes.

Jan 1, 2003

By S Williams

The primary objective of most mining projects is to maximise the value delivered to the companyÆs shareholders. Achieving best practice performance and maintaining competitive advantage through low-cost production and high productivity is essential to achieving this aim. Benchmarking is an essential tool for the identification and implementation of best practice performance, and to realise continuous improvement by ensuring best practice becomes common practice. But to be successful, that is to deliver long-term value creation, benchmarking must be holistic and align operational performance with strategic intent. This paper outlines a rigorous and structured approach on how to conduct a successful benchmarking program that aligns operational performance with the businessÆs goals. Further it investigates the benefits that benchmarking can provide throughout the project life cycle and provides some key learnings from some of the worldÆs leading miners.

Jan 1, 2009

The importance of proper planning, preparation, and execution of a steady state sampling campaign for metallurgical plant assessment must not be underestimated. Careful planning can increase the amount and reliability of information from an optimum number of samples and fully utilize available plant data. It requires specification of the data required, determination of run duration sampling frequency, the selection, modification and testing of sample points and cutters, as well as organisation and briefing of plant and sampling personnel. Preparation immediately prior to sampling, the conduct of the sampling campaign itself and procedures to handle the collected samples and information are discussed. Cutter design, fabrication and use are described in detail, and typical sampling situations, for ball mills, classifiers, pipes, launders, flotation cells and thickeners are considered individually. Measurement of pulp flow rate can often resolve difficult mass balance problems, and discussion of convenient techniques is included.

Jan 1, 1976

By Marshall K. I

THE problem of satisfactorily eliminating the fumes and dust which are unavoidably produced in various metallurgical and manufacturing industries is one which has received considerable attention in the past, and has been the subject of much investigation and research. The solution of this problem was urgently desired for two reasons, the principal one being the fact that a considerable percentage of the total process losses in many industries was represented by the commercial values of the fumes and dust that escaped from the stack.The other reason is that, in some instances, the emission of the matter is regarded as objectionable. Various methods have been designed with a view to solving the problem thus presented, and the latest development that has beendesigned is the process of electrostatic precipitation. Continued investigational and developmental work with this process has already demonstrated its applicability to many industries, and new uses to which the process can be put are being opened up. Its use is already widespread, and the economic success that has attended its application in most instances would indicate that its use will become more general in the future.It has proved its ability to treat gases over wide ranges of temperature, and has successfully handled various types of fumes whose chemical characteristics differ very considerably. In many processes it has now come to be regarded as standard equipment.HISTORY OF ELECTRICAL PRECIPITATIONThe first recorded observations on the influence of an electrified insulated wire on gases containing solid particles in suspension was made as early as 1824 by Hohlfeld, in Leipzig. He found that, if he electrified a wire hung in a bottle filled with smoke, the smoke cleared rapidly, and a deposit formed on the sides and bottom of the bottle.

Jan 1, 1923

By Huajun W, Long LZ

The composition of fly ash and formation mechanism of cennospheres are introduced in this paper. The signification of using this potential new mineral processing resource is emphasised. The beneficiation properties of the components of fly ash, such as susceptibility, specific gravity, size, shape and flotability etc have been examined in detail. A technique was designed to process fly ash from the XiGaoJing power plant in Beijing, and a flowsheet is also presented. Flotabld cennospheres, magnetic beads, sinkable beads, carbon and advanced pozzolamics can be obtained as separate products through this flowsheet. It is emphasised that the beneficiation of fly ash is an efficient means of totally utilising the resource. Examination of the products show that they have good physico-chemical properties. Possible areas of their application are also Suggested.

Jan 1, 1993

Flotation science and technology are related to three major sub- processes which are organized in a hierarchical structure as shown in Fig. 1. The basic sub-process is the chemical process which affects the attachment of air bubbles to mineral particles. In particular, the chem- ical process is related with the adsorption of surface active sub- stances at the gas-liquid, liquid- solid, and gas-liquid-solid inter- faces. This field has been most intensively explored in flotation research. The second domain in flotation research is concerned with the mineral particle to air bubble attachment sub- process in the system. This sub- process represents the dynamics of particle and bubble encounter where the contact angle and the induction time, determined by the surface chem- istry of the system, are among the most significant parameters. This sub-process can be referred to as the micro-process as against the third sub-process, or the macro-process, which corresponds to the integral behaviour of the system. Two other sub-processes are integrated into the macro-process in which they may not reveal themselves explicitly in the details. The third sub-process does not entail surface-chemical or physi- cal events any more, but it represents them all inclusively. To represent this sub-process we use mathematical equations, called models. Only in some simple or simplified cases can the models be solved exactly to find out the behaviour of the flotation system in which we are interested. Digital

Jan 1, 1984

Anyone who has driven backwards using only their rear view mirrors knows how difficult it is to avoid spinning the steering wheel the wrong way. So why run your mine that way? Traditionally Reconciliation has focused on the past performance of the mine. In this paper we make a case for Prognostication û the act of forecasting or predicting something in the future from present indications or signs. Reconciliation is a common activity carried out at most mines around the world. Countless geologists and engineers spend hours poised in front of spreadsheets diligently comparing how their resource/reserve model, grade control, and survey pick ups compare to what was actually produced. The result is usually a group of factors, which are applied to future estimates in an attempt to better predict how the operation may perform. Unfortunately, if the road ahead isnÆt the same as what you have just been down, youÆll be æoff-roadingÆ in no time! An alternative is to constantly collect and analyse key measurements that are used to calibrate critical estimates in an iterative process. When variations occur, they are analysed and corrective action is taken to ensure the estimates and measurements realign. In this way the estimates become forecasts and can then form the basis for decision making to ensure that what does happen in the future will match the plan or schedule. By automating this process, some mines have been able to be proactive on a daily basis in order to improve the overall performance of the operation. This paper outlines the key estimates and measurements used for reconciliation, details the characteristics of an automated web based information management system to facilitate the process and provides some insights about how mining operations might move beyond reconciliation.

Jan 1, 2003

By J J. Laas, A J. S Spearing

Considering the capital outlay, running costs and inherent difficulties of backfilling operations at depth the benefits need to be clearly established, quantified and then exploited. Expansion of Vaal Reefs Exploration and Mining Company towards even deeper, highly faulted ground, and the process of establishing codes of practice for the management of rockfalls and rockbursts, required that a sound support strategy be formulated. This paper describes the derivation of an overall backfilling strategy on Vaal Reefs. Use was made of experience gained over some 12 years with backfilling. Numerical modelling was used to estimate potential benefits of backfilling the deepest mining areas still to be extracted. In exploiting a probably unique opportunity, two contiguous mining areas bounded by the same major geological structures, were compared. One was extensively backfilled and the other not at all. Shaft sinking through a backfilled stope added another dimension to the database.

Jan 1, 1998

The developments in hydrocyclone classification in the milling circuit at Bougainville Copper Limited are discussed. A major change in cyclone size and improve- ments in operating conditions have been made. Test work has been carried out to assess the classification performance of a modified Linatex cyclone, Wemco cyclones and a two stage cycloning circuit. The use of a scalping cyclone, to remove coarse material from the present overflow product for regrind, has also been investigated.

Jan 1, 1978

In the retreatment of an old tailing dump containing five per cent of lead principally as lead sulphate, the lead sulphate was floated with liquid Aerofloat reagent after sulphidising with phosphorous pentasulphide in an acid circuit. A zinc middling product was removed by flotation before recovering the lead. Concentrate products were sundried in surface dams.INTRODUCTIONDuring the period between 1917 and 1928 the Junction North Broken Hill Mine N.L. deposited several tailing dumps on its leases, which were acquired by North Broken Hill Ltd.in 1931. One of these dumps lay alongside a main road close to a residential area. The high metal prices prevailing in the post-war years (1945 onwards) provided a strong incentive for retreating this dump and transferring it to a less objectionable site.SAMPLING AND TESTINGIn 1946 a sampling and testing campaign was instituted which culminated in 1949 in a decision being made to erect a tailing retreatment plant adjacent to the dump.The dump was sampled with a 3 in. post hole auger using extension lengths of -! in. pipe for drilling to 30 ft. The dump material was fine and moist and core recovery was excellent. Hole depths ranged from 14 ft. to 30 ft., with an average dump depth of 20 ft.Individual samples were prepared from successive 9 ft.lengths of core and each sample thus obtained was, submitted for sizing and assay.The sampling showed that the dump contained approximately 380,000 tons of fine tailing assaying:

Jan 1, 1956

By M Logsdon, T R. Clark, T I. Mudder

Oxidation of pyrite and other metal sulfides is accelerated by the activity of acidophilic iron- and sulfur-oxidising microorganisms. The ideal biocide for controlling biocatalysed acid rock drainage (ARD) would be inexpensive, inhibitory toward sulfide-oxidising bacteria at low concentrations, relatively non-toxic toward non-target organisms, degradable in the environment outside the zone of application, stable and long-lived in the impacted environment, sufficiently mobile to penetrate into piles of waste rock or tailings, and effective regardless of the metal sulfides present. A potent agent for combating ARD that fits these criteria is the thiocyanate anion (SCN-). The objective of this study was to determine the effectiveness of thiocyanate in controlling or preventing ARD within several types of sulfidic waste rock and tailings. Results were evaluated within a context encompassing process water and solids management strategies employed at different precious and base metal mines. Sulfidic rock was treated with solutions of potassium thiocyanate and subjected to accelerated weathering tests in lab-scale humidity cells, trays, and columns. Certain tests also utilised solid phase copper thiocyanate (CuSCN) to evaluate a ærelease on demandÆ strategy. Leach solutions were analysed for parameters indicative of ARD including pH, redox potential, conductivity, acidity, sulfate, iron, and certain heavy metals. Two larger scale field tests were also initiated by personnel at separate mines using, in the first case, ore containing a pyritic component in large columns and, in the second case, waste rock containing base metal sulfides in lined pits. Humidity cell tests showed low concentrations of thiocyanate solution applied to pyritic waste rock could reduce ARD formation by 90 per cent or more compared to untreated controls, with the residual release of ARD components (eg sulfate, Fe, acidity) probably reflective of strictly chemical oxidation of the sulfides by molecular oxygen. Thiocyanate applied at a concentration of 22 mg/kg to waste rock from a base metal mining operation in large laboratory scale columns reduced acidity and sulfate release by 75 per cent to 80 per cent compared to untreated controls. This extent of reduction in ARD may not meet discharge water quality criteria, but has the potential to significantly reduce lime consumption and sludge production in a conventional neutralisation facility. The use of a solid-phase metal thiocyanate compound (CuSCN) at a dosage of 194 mg/kg pyritic ore resulted in the following per cent reductions in leach solution parameters in comparison to controls: sulfate (78 per cent), acidity (93 per cent), dissolved Fe (99.4 per cent), and dissolved arsenic (99.9 per cent). This compound has the further advantage of being relatively stable until needed, dissolving only in the presence of an acidic and oxidising ARD solution. If this line of investigation progresses favorably, it offers the possibility of an ARD prevention technique that may be applicable in some settings. Mine-site pilot scale tests with pyritic ore resulted in reductions in sulfate (56 per cent) and Fe, As (66 - 68 per cent). In sum, thiocyanate at relatively low concentrations dramatically reduced ARD from sulfidic rock in a simulated heap. The pilot test using waste rock containing base metal sulfides has begun only recently. A preliminary process design and cost estimate was made for fullscale application of thiocyanate to waste rock at a hypothetical gold mining operation producing 5000 tpd of ore and 10 000 tpd of sulfide containing waste rock. The combined capital and operating costs for the full-scale thiocyanate application facility were about $US 0.25/tonne of waste rock and $US 0.50/tonne of ore. Although thiocyanate is readily available commercially, it also occurs in process solutions associated with certain types of mining processes. Such solutions after selective treatment might be recycled to sulfidic waste rock or tailings, rather than being treated for thiocyanate degradation.

Jan 1, 2003

Kambalda Nickel Mines (KNM) currently have eight operating underground mines, three on care and maintenance and other orebodies at various stages of development. Each operation differs greatly in scale, ore grade, milling characteristics and cost structure. The optimum number of mines operating at any one time and their level of production, within the constraints of mill blending requirements and overall mill capacity, is the key to maximising profit in a climate of fluctuating nickel price. Cost models are developed for each mining operation which relate ore tonnes mined to total cost per pound of nickel produced from that mine. Aggregating the mine cost models provides a composite cost model for the entire operation. The cost models provide the operating levels necessary for each of the mines and hence Kambalda as a whole, to operate at the lowest cost per pound of nickel produced. However, lowest operating cost does not necessarily lead to maximum profit. The level of nickel price above operating cost can dictate maximum profit positions which are contrary to the lowest cost position. In addition, the decision to temporarily shutdown mines or reopen mines in response to nickel price movements comes at a cost. In considering the optimum operating position, the price of production capacity flexibility needs to be taken into account. This paper describes the process used to assess all these factors in arriving at the optimum operating position for Kambalda Nickel Mines for varying nickel prices. The same methodology can be used by corporate management in managing multiple mine sites as well as mine management managing multiple orebodies or stoping blocks for maximum profit.

Jan 1, 1995

This paper is intended to continue the subject in the light of recent work, from where it was left at the conclusion of the discussion on the excellent paper by the late Mr. Noel Haszard. The position then obtaining is briefly summarised below:-The points which received general agreement at that time were:-'(1) That the gold occurs, probably in an elemental form, in a state of very fine division in the pyrite.(2) That the aim in roasting of Kalgoorlie flotation concentrates should be to obtain the maximum porosity possible. The gold tellurides were amenable to treatment with either a' solution of high lime and cyanide strength combined with fine grinding, or bybromocyanidation without re-grinding.(3) That a low roasting temperature is essential during the elimination of the first atom of sulphur, if the final calcine is to give a good extraction by cyanidation.(4) Even with the best temperature conditions of roasting then determined, and after a period of cyanidation of the calcines until no further extraction was obtainable, the lowest calcine residues obtainable were equivalent to approximately 1·8 dwts. per long ton, based on an original concentrate of pure pyrite.There was some division of opinion at the time as to whether the temperature of the later stages of roasting was significant, and also as to the reason why the initial roasting temperatures had so marked an effect.

Jan 1, 1939

By Ride G

The provision of a water supply is a major consideration in planning mining developments particularly in remote areas. The evaluation and development of adequate water supplies in and areas of Australia is often as important as the discovery of the orebody. The copper orebody at Warrego near Tennant Creek could not be mined economically if cheap treatment water was not available near the mine. This paper describes the difficulties in obtaining water in the Tennant Creek area and the water supply investigations carried out near the Warrego Mine which resulted in the successful discovery and evaluation of a reliable large scale water supply. It is contended that the establishment of a water supply must be approached on a systematic and scientific basis similar to the approach with the exploration and establishment of actual ore reserves. Mining companies with similar water supply problems may benefit by approaching their problem on this basis. The approach adopted by Peko Mines is outlined in this report.

Jan 1, 1980

Fission track thermochronology is a well established method for reconstructing the thermal histories of rocks with particularly important applications in tectonic studies, detecting low-grade thermal events, sedimentary basin analysis and resource exploration. These applications take advantage of the limited stability of fission tracks, especially in apatite, when exposed to the temperatures found in the upper 3-4 km of the crust. Apparent fission track ages in apatites can define an invisible 'stratigraphy' in otherwise homogeneous rock masses that can give valuable information on thermal, tectonic and erosional events. Quantitative modelling of the thermal annealing of tracks in apatite shows that distinctive profiles of apparent fission track age can be related to a number of simple thermal history styles. The main types of profile observed tend to be either an essentially linear decrease of apparent age with increasing depth, which relates to continuous uplift and denudation, or a concave-upwards profile produced by partial annealing in environments of tectonic stability or burial. More complex thermal histories produce compound profiles which are essentially just combinations of these two elements. Track length information allows the apparent age profiles to be interpreted in much greater detail. Examples of the major profile types have now been identified in various geological environments and can be analysed to give information about, for example, uplift and denudation rates, the timing of uplift or low-grade thermal events and maximum palaeotemperatures experienced during burial.

Jan 1, 1990

The working of alluvial deposits has from all times been a popular form of mining, not only from the simplieity of its operations, but also, in its more primitive stages, from the possibility of carrying it on without large capital, without skilled lahour, expensive plant, long terms of preparatory work, or, in fact, any other requisite than a shovel, a dish, and a stout pair of arms. It is possibly one of the oldest industries, and probably, also, it has been one of the most profitable.In tbe Australian States the happy days of rid alluvial deposits, when gold was to be hltd for the shovelling, are now almost over. The lust for gold has caused almost every corner of the world to be ransacked, and the more easily earned wealth to he exhausted: for the most part there remain now those deposits only which are too poor to be profitably worked by means of the implements and methods of old times. But, though the deposits have become poorer, the keen inventiveness of man has devised means whereby such large quantIties can be treated at a cost so low that he can still make a profit out of them. In this article, out of the many means devised, three only will be referred to-viz., hydraulic sluicing, bucket dredging, and hydraulic dredging. All mining may be divided into three principal operations-1st, the breaking down and conveying of the ground to where it is to be treated for the recovery of the metallic values, 2nd, the treatment of the material for the recovery of those values; and, 3rd) the removal of the worthless material or tailings. In all mining the object is to effect these three processes for the least expenditure of money commensurate with the highest degree of efficiency.

Jan 1, 1907

Over years of exploration the massive and tabular orebodies in the area to the South West of Western Areas Gold Mine had been assessed as containing about 50 million ounces of gold û a world class orebody. Planning initially was for a surface and subvertical shaft system to exploit this area but because of cost, a single lift shaft to an area which could be accessed ex Western Areas was planned to intersect the reef at 2760 metres. It was also planned to mine out the shaft pillar area long before the deep shafts would reach that position. This is not the normal practice in South African Gold Mines. The stoped out shaft pillar was backfilled to minimise movement in the shaft sites. The result of a competitive tender/adjudication process was that Cementation Mining û Skanska won and was awarded the R192 million contract to sink the Main and Ventilation Shafts on 15 June 1995. On 1 April 1999 Western Areas and Placer Dome SA formed a Joint Venture, which now owns and operates the mine on which the South Deep Shafts are situated. This situation prevails today.

Jan 1, 2002

Modelling of Magnetic Carrier Separation Process Using Computational Fluid Dynamics

Sep 13, 2010