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By Carter D

The Chairman of this afternoon's session is Dick Carter. This afternoon is the culmination of this conference. We've looked in the first session at regulation; in the second session at valuation techniques and this session we look at valuation in practice. Dick's involvement in the mineral industry has been wide ranging and distinguished. Dick has worked with BHP since 1960, when he joined BHP Steel as a commercial trainee. Dick holds a B.Comm. from the Newcastle University College of the University of New South Wales and was educated at the Australian Administrative Staff College and Harvard Business School Advanced Management Programme. During the past decade, he has headed the minerals group's Aluminium Divison, Resource Planning and Development, Non-Ferrous Metals and Business Development Organisations. Dick currently serves as Executive Director of BHP Gold Mines Limited and Managing Director of Ok Tedi Mining Limited. His experience covers Australian Manganese Company, Mineral Deposits Limited, Northern Rivers Rutile, Tasmanian Electrometallurgical Company Limited, Mount Newman Joint Venture, Worsley Aluminium and Carnilya Hill Joint Venture Operating Committee. His industry associations include the Executive Board of the Gold Producers Association, the Federal Executive of the Australian Goldmining Industry Council as well as the World Gold Council. Ladies and gentlemen, Dick Carter.

Jan 1, 1989

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

By Meakins R. L, Talaska A, Kenny D, Haycraft J. A, Dickson B. L

A vehicle-mounted radiation detector interfaced to a microprocessor called PRAM (programmable radioactive analyser mobile) has been developed to provide grade control for selective mining of a soft rock uranium ore. The grade of ore over which the vehicle passes is determined and indicated by several coloured lights to a pegman who walks behind the vehicle. Coloured pegs are then laid out to mark the uranium grade ranges on the floor of the mine pit. Comparison between grade ranges determined by the PRAM and by prior drilling and downhole logging at the Yeelirrie deposit, Western Australia indicate good agreement. Use of the PRAM decreases the cost, manpower and time required to grade extensive areas of a mine pit floor.

Jan 1, 1982

The Callie Underground Mine is located in the Tanami Desert 560 km Northwest of Alice Springs in the Northern Territory and is currently operated by Newmont Australia Limited with all mining activities carried out by Henry Walker Eltin. Callie was discovered in the region in 1991 with the box cut portal commenced south of the pit in 1995 and underground ore production commenced in 1998, after completion of the profitable Callie Open Pit. Development is currently occurring at depths of over 700 m with the decline currently below the 640 Reduced Level (RL) level (surface RL of 1400) with production haulage from 600 m below the surface. The combination of auto compression, a moderate geothermal gradient of 2¦C/100 m and diesel heat transfer causes the wet bulb temperature of intake air at the bottom of the mine to be typically 5¦C higher than on the surface. Wet Bulb temperatures can be up 5¦C higher again in active areas under secondary ventilation. During the 2002/2003 wet season many activities in the lower levels of the mine were stopped due to miners experiencing adverse heat related symptoms or the temperatures exceeding the Underground Heat Management Procedure stop job criteria of 32¦C wet bulb. To improve the working environment, combat the heat related illness and improve operational efficiency, a temporary 1.8 MW refrigerated cooling plant consisting of three 600 kW modules were installed underground to provide bulk air cooling for the lower levels of the mine during the 2003/2004 wet season. Several studies have been conducted in relation to future ventilation demands at Callie and all came to the conclusion, that some mine cooling will be necessary for Callie to meet the high production and development demands. This paper will describe the ventilation network at the Callie Underground operation focusing on the installation, operation and effectiveness of the temporary underground refrigeration plant.

Jan 1, 2005

This paper discusses the concepts of core risk associated with mining projects and operations and illustrates the types of core geotechnical risks and consequences that may relate to a range of different mining methods, with recommendations on risk management procedures to ensure that the core risks are under constant and ongoing scrutiny and priority management focus. These core geotechnical risks can and should be identified at the initial mining method selection stage, during a feasibility study. They should form part of the auditing of the project and the decision-making regarding the project viability. They should then be built into the ongoing management structure of the project, right through into ongoing operations, with regular audit and review.

Jan 1, 2003

The last decade of national water reform implementation has improved the availability and efficiency of water source allocation in Western Australia. However, it is critical to recognise that the concurrent mining boom witnessed the approach of full water allocation limits, and increasing trends in mineral processing, water infrastructure costs, and wastewater management costs. Water supplies are commonly viewed as absolutely critical to project feasibility in mining, industrial and energy generation projects, even if considered 'non-core business'.   An increasing density of mining projects and industrial estates in Western Australia (WA) creates an opportunity for water infrastructure cost sharing and synergies. The WA government and its agencies have given preliminary consideration to the establishment of independent water utilities in the goldfields (Kalgoorlie), the Pilbara, and Collie regions, and in the Kwinana Industrial Area. The impending Oakajee industrial area and Mid West regional development, and Anketell port in the East Pilbara, could also be considered for common non-municipal water supplies.   The critical issue of apparent commercial risk due to the large scale of water demands and the low customer numbers in the minerals sector relative to other water markets is expected to mandate government partnership in any non-municipal water utility ownership. The commercial feasibility risk is observed as a risk to water supply security for potential mining and industrial customers. Absence of proper water infrastructure planning and governance has the potential to create infrastructure access issues as observed for Pilbara rail developments under the Trade Practices Act 1974.   Other aspects of water cycle management which could be addressed by a non-municipal utility include resumption of mine dewatering water (required changes to WA legislation that are progressing) and consolidated wastewater management for maximising synergy or reuse opportunities and minimising cumulative environmental impacts.   Address of water infrastructure planning for non-municipal water demands must cover commercial and environmental sustainability outcomes to successfully progress minerals sector growth in the State.

Jun 1, 2010

By G J. Sparrow, M J. Fisher-White

A mineral and chemical characterisation study was conducted on ilmenite-rich heavy mineral concentrates sourced from the western sector of the Eucla Basin in southern Australia. Test work involved using X-ray diffraction (XRD), scanning electron microscope (SEM) and electron microprobe-based characterisation methods. Results showed considerable variability in the degree of ilmenite alteration between deposits with TiO2 contents varying from 53 - 63 wt per cent TiO2. Notwithstanding variability between individual deposits, the samples all had [Ti]/[Ti+Fe] ratios >0.5 consistent with a mineral assemblage of hydrated ilmenite or the hydrated, Ti-rich alteration phase pseudorutile (Fe3+2-x Ti3O9-3x (OH)3x). Accessory phases consisted of rutile (primary and secondary), zircon, aluminosilicates, quartz, Fe oxyhydroxides and spinels. Results for the most altered material are broadly comparable with data for ilmenite concentrates from the eastern margin of the basin. The mineralogy of the western Eucla Basin concentrates and the minor element composition of the ilmenite grains suggest they could be upgraded to synthetic rutile by a modified Becher process.

Jan 1, 2008

By Bekturganov NS, Satayev I

The paper deals with the effect of sodium polysulphides in chrysocolla flotation. Activity of elementary sulphur adsorption on the mineral surface is discussed. The mechanism of polysulphide action in the process of sulphidisation and formation of sulphur on the mineral surface is proposed. Sodium pentasulphide is shown to be the most effective modifier of chrysocolla flotation.

Jan 1, 1993

By K Hskansson

In earlier studies along a mining region recipient (the river VormbScken, northern Sweden), the fraction of certain trace metals recovered in the particulate phase has been found to increase with increasing concentrations of particulate iron. This study was conducted to see if the pattern could be reproduced by adding minor amounts of ferrous iron, simulating groundwater inputs. When the iron is oxidised in the near neutral river water, it will form iron oxyhydroxides and precipitate. Trace metals may be either co-precipitated along with the iron, or adsorbed onto the freshly formed precipitates. If this is the case, such a mechanism may be incorporated as a part of a final polishing step in a mine drainage treatment system based on natural attenuation processes. The experiments were performed at 0¦C and 22¦C, on authentic river waters collected during the winter and summer of 2002, respectively. In order to investigate the influence of particles and bacteria initially present, filtered river waters (4 solution were added to the experimental beakers, increasing the iron content of the waters by 0 - 1.5 mg/L. The oxidation and precipitation processes were followed by means of filtration (0.2 ¦m) for up to seven days. In order to be able to compare the experimental results with the actual field situation, on both experimental occasions, surface water samples were collected also from three stations situated along the river. The samples collected were analysed for iron, calcium, and trace metals by AAS and ICP-MS. The iron oxyhydroxides formed in the experiment did not influence the partitioning of As, Cu, and Pb to the same extent as the particulate iron encountered along the river appeared to do. Cd and Zn were recovered mainly in the dissolved (

Jan 1, 2003

By C McMahon, S G. Walters

Mineral maps of æintactÆ and large particle textures have been produced routinely from optical microscope images. Polished thin sections of large particles (1 - 3 mm) provide a balance between representative sampling and the preservation of primary rock textures. Optical microscopy is an efficient way to generate mineral maps suitable for geometallurgical applications. The automated optical mineral identification was carried out using a Leica DM6000¬ microscope with a high precision stage suitable for direct tiling of image frames and good registration of multiple image layers. Standard images collected were 10 x 10 frames (20 mm x 16 mm). Four image layers were recorded: ætransmitted light plane polarisedÆ, ætransmitted light crossed polarsÆ, ætransmitted light crossed polars with 1l tint plateÆ and æreflected lightÆ. All image analysis was carried out using Definiens Professional V5¬. The four image bands were read directly in 12 greyscale bands. A segmentation algorithm produced objects based on homogeneity across all bands. These objects were then classified using a complex set of rules (Process Tree) that are based on image brightness in all 12 bands. Opaque and non-opaque minerals were classified in the same sample. Using this protocol up to 12 minerals can be satisfactorily classified in one sample. The opaque minerals were recognised using colour ratio and reflectance intensity in the reflected light image. Non-opaque minerals are more difficult because of the complex variable colours of many minerals and the complexity of interference colours. However, object-oriented classification using three transmitted light image layers and multiple rules is a powerful technique for recognition of these minerals.

Jan 1, 2008

The law including legislation such as the Occupational Health & Safety Act 1983 imposes stringent obligations on employers to ensure the health and safety of their employees. The use of pre-employment medical examinations is one tool that employers can use to assess the suitability of a job applicant for a particular position and protect themselves from prosecution or claims for compensation or damages.At the same time, however, legislation such as The Disability Discrimination Act 1992 (Commonwealth) ("DDA") and The Anti-Discrimination Act 1977 (New South Wales) ("ADA") affords protection to individuals against discrimination.

Jan 1, 1998

With more difficult economic conditions and increased competition, the Australian exploration industry is allocating increased resources to developing more effective and efficient exploration technologies. A significant number of new techniques have been developed, and Australian companies are now at the forefront of exploration technology worldwide. These should increase the chances of maintaining Australia's leading position in world mining over the long term.

Jan 1, 1987

The paper describes major principals in hydrodynamic test- ing of horizontal and inclined boreholes using flowmetering and pressure build-up techniques while tunnelling and dri- ving permanent workings through water bearing rock and fau- lted zones. A number of case histories is given together with the description of technical means and special equip- ment.

Jan 1, 1988

By P D. Munro

The Mine to Mill concept, as it has become known, is a philosophy which is being increasingly embraced by mining companies committed to increasing their profitability through better integration and global optimisation of their mining and processing operations. Autogenous (AG) and semi-autogenous (SAG) mills are the principal primary grinding devices currently in use, their performance is particularly sensitive to feed size distribution. Most efforts to-date have centred on modifying and controlling the run-of-mine (ROM) size distribution to maximise grinding mill throughput. The complexity of the interaction between ROM size distribution, primary crusher product and AG/SAG mill performance precludes the trial-and-error approach as an effective means of determining the optimum blast-induced fragmentation size distribution. To overcome this limitation, the Julius Kruttschnitt Mineral Research Centre (JKMRC) has developed modelling and simulation techniques that are able to accurately reproduce both the fragmentation processes during blasting and the subsequent performance of the comminution circuit. These models are tailored to suit local ore types, rock structure and comminution circuit design and calibrated using high quality field data. MIM Holdings Limited (MIM) have been particularly active in the Mine to Mill area and have instituted optimisation programs at three of their associated base metal operations viz Alumbrera, Ernest Henry and the Mount Isa Mines. This paper describes these programs with particular reference to the data acquisition and modelling phases, the predictions of potential productivity gains and the extent of the realisation of these gains to-date.

Jan 1, 2000

Zircon is extensively used as moulding sand in the production of steel and high-duty iron castings. To achieve a satisfactory grade of zircon concentrate, the zircon particles may need ,to have surface coatings removed, as such coatings can hinder electrostatic and magnetic separation of zircon from associated minerals. Xn addition the presence of surface coatings on the zircon. particles can cause sinterins and fusion of the zircon to the east metal resulting in "burnt-on" sand or fritting of the casting. "Burnon" necessitates cleaning of the casting by grinding or chipping, which is expensive and results in loss of definition on the casting face.Hudson (1966) has pointed out ,that some coatings on mineral sands are lightly-adhering clays which can be removed quite readily by agitating the sands in water for a few minutes-thus their removal constitutesno problem. However, the heavy gingery coloured coating which adheres strongly to the surface of the particles in some deposits, and which has generally been considered to be a form of iron oxide (Baker, 1962; Hudson, 1966), cannot be removed effectively by attrition cleaning in water (Hudson, 1966). Such coatings limit the usefulness of these concentrates in the foundry industry.An investigation of strongly-adhering coatings on "ginger zircon" concentrates from the Yoganup deposit of Westralian Sands Ltd has shown that the stain consists of a cemented mixtvre of hydrated iron and aluminium oxides and kaolin minerals, and that it can be removed by a relatively low cost treatment.IDENTIFICATION OF THE STAIN BY XRDX-ray powder diffraction (XRD) patterns were obtained from small samples of stain scraped, individually, from the surface of hand-picked zircon and ilmenite crystals. These scrapings were mounted on quartz fibres and exposed to CoKa radiation in a 57 mm Debye camera. To avoid heavy fogging of the x-ray films, a substantial amount of the iron oxides was preferentially leached from the scrapings (before mounting) with an ammonium oxalate-oxalic acid solution (Rooksby, 1961). The residual material gave a fairly well resolved powder pattern (Table 1). A...

Jan 1, 1975

Mary Kathleen Uranium Ltd. recommenced operations in early 1976 following a twelve year period of care and maintenance. Several sections of the plant were modified or completely changed for the second operation. The most important change was the replacement of ion exchange with solvent extraction as the means of purifying and upgrading uranium rich Isolutions Most of the problems experienced in the solvent extraction system originate from the leach liquor which has a strong tendency to form stable emulsions. This has been countered by some careful control of leaching conditions and by closer observation of operations in the solvent extraction area. Most problems have now been resolved and plant recoveries are quite Satisfactory.

Jan 1, 1978

By J Sarvinis

The design and operational aspects of fluidised solids transfer-cooling devices will be discussed in this presentation. The devices include air slides and fluoseals (also called seal pots, loop seals, etc), which are widely used in metallurgical plants and other processing plants. Cooling can be achieved while solids are transported in the solids transfer devices. The units combining solids transfer and cooling provide compact and clean plant layouts and also reduce capital and operational costs. Fluidised devices provide excellent gas-to-solids and gas/solids-to-surface heat transfer rates, hence high cooling efficiency. Fluidising gas, such as air, nitrogen or other gases, can be used as direct cooling mediums. Coolants such as water, steam and other liquid or gas cooling fluids can be used as indirect cooling mediums via tube coils immersed in the fluidised solids. The fluidised transport devices share some common features with fluidised bed equipment. The air slide is similar to a linear fluidised bed while the fluoseal is similar to a circular fluidised bed. Therefore fluidised bed design techniques are applicable to the design of the air slides and fluoseals. The heat and mass balance and temperature profiles of the devices concerned will be discussed in the presentation. The design criteria and operational philosophies of the critical components such as tuyeres and air spargers will also be discussed.

Jan 1, 2006

By Morris A. E

The thermodynamically-based pyrometallurgical simulation software STEPSOL (Version 3.0) provides for the modelling of activities using the Interaction Parameter Model, the Regular Solution Model, the Sub-Regular Three Suffix Margules Model, the Sub-Regular Four Suffix Margules Model and various simpler polynomial models. These are briefly reviewed, along with the major sources of data available in the literature, and the implementation of the models in the program.

Jan 1, 1992

This paper shows how small calculators can be used for ball mill simulations. Two calculations are examined, the first to calculate the mill parameters and the second to predict the mill product. In the case of small programmable calculators the programs for two common models are given.

Jan 1, 1976

The design, construction and operation of a 500,000 tonne per year Carbon-In-Pulp (C.I.P.) plant at Kambalda embracing the period from 1980 to 1982 has been previously discussed (Sceresini, 1982).Since that time the annual throughput rate has increased to 780,000 tpy.This paper discusses the changes and improve-ment made to allow this increased production to occur with minimal capital expenditure.

Jan 1, 1984