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The æProfit Driver ModelÆ is a tool which builds costs from first principles and integrates revenue, costs and physical mining parameters and, hence, can quantify the impact and leverage on profit. In this paper an æexample mineÆ has been created to represent a typical Australian Open Cut Coal Mine. This has then been input into the Profit Driver Model to allow different variables to be tested. A series of variables were tested to determine which ones had the highest impact on profit and results are useful to management as a guide to the areas in which they can focus effort to achieve better profitability. Whilst the highest profit drivers are those external to the control of management and include selling price and exchange rate, the next most sensitive are those variables related to the geology of the mine and the mining method. These included coal quality, yield and strip ratio. Site management has some control of these. For example, the ability to vary the sequence of mining or improve the yield by a more efficient coal washing process. The efficiency of the workforce and management has similar impact to the mining variables. Finally, there are the supply variables, such as fuel, labour and explosives which are the least sensitive although, cumulatively, still significant. Each mine is different and the results of the example mine will not apply to all mines. However, the approach taken is universal and the tool illustrates a simple method to quantify the profit impact when changing variables. The benefit of the approach is the short time taken to get a set of results. This allows the more detailed and time consuming work to be more focused. The results illustrate that management has a significant influence on profitability.

Jan 1, 2000

By R Lloyd

Coal Services (Health and Safety Trust) funded ARRB Transport Research Ltd to investigate fatigue and performance of truck drivers over consecutive shifts. The main questions were to assess: What is the most important contributor to acute fatigue in mining? Is it length of shift (eg eight hours versus 12 hours) or is it time of day (eg circadian effects)? What is the limit of successive day or night shifts before chronic fatigue affects operator performance in open cut mines? The project methodology included utilising ARRB Fatigue Monitoring Devices (forced-choice stimulus reaction) in eight haul trucks, testing 24 subjects over several weeks. Each subject filled in a Fatigue Risk Questionnaire on lifestyle and health. Operators worked a 14-night, one day off, 13-day roster of 12-hour shifts in a fly-in/fly-out operation with excellent opportunities for restorative sleep between shifts. A total of 3500 hours of real-time data was collected, representing the first set of objective, real-time driver performance data for Australian mining. The data showed that for a single night of driving haul trucks, there appears to be no effect on operator fatigue from the amount of time on task (for the 12 hours). In fact performance was worse through the first eight hours than the last four. The circadian influence had a stronger affect than working more than eight hours. Of the 14 nights worked at the site, nights 13, 14, seven and two respectively, were the worst. This presents a conundrum for policy makers who may like to place caps on working hours or rosters in the hope that it will alleviate the fatigue issue. It will not. The major finding within this study is the combined influence of circadian rhythms (human body clock) and individual variability on performance. The lifestyle habits and the health of individuals have a profound effect on operator performance as shown by the strong positive correlation between high fatigue risk scores from the Fatigue Risk Questionnaire and poor performance. An individualistic approach would appear to have the best chance of reducing high potential incidents due to fatigue through successive nightshifts.

Jan 1, 2005

Ranger Uranium Mines (RUM) operates an open cut located in the Top End of the North- ern Territory. Strict environmental controls govern all operations and the water management requirements have the greatest impact on mine planning. The two main goals of planning are to provide mill feed and to mine sufficient suitable quality waste rock for ongoing con- struction of the tailings dam. Early planning concentrated on staged development of the pit to provide access to as much ore as possible for a given amount of development. All waste was considered to be suitable construction material. Grade control of crusher feed was the main problem in planning, as wide vari- ations occur in ore grade over relatively short distances. Water management for the site ope- rates a no release' system for contaminated waters. Design storage has proven inadequate, and the open cut has been used as the extra storage. As construction of future stages of the tailings dam requires non-mineralised rock materials which meet specific quality criteria, the mine has had to re-examine long term plan- ning and pit development strategies. This has entailed the collection of much data not re- quired under normal mining conditions, such as the assaying of waste drill core. The overall impact on mine planning of the environmental regulations has been to alter the philosophy of earlier planning, making it necessary to create a new strategy for pit development with

Jan 1, 1984

By C Sennersten, A Hellicar, C Lindley

Traditional methods of resource modelling and mine planning rely upon geostatistical methods applied to exploration drill core data to derive a three dimensional model of the distribution of metal grades, quantised into rectangular prisms or blocks. The resulting block model is a primary input into short, medium and long term mine planning. However, block attributes are averaged or interpolated over a complete block, meaning that information at smaller scales is lost to the mine planning process. Grade engineering for new mining methods, such as the development of more accurately controlled blast designs, continuous miners for hard rock and sensors for rock properties that can be distributed along the operations process and value chain, allows excavation to be much more selective than traditional blasting, and provides data for driving earlier separation of waste from ore. This selectivity can be optimised if the resolution of resource models can match or exceed the spatial resolution of selective mining technologies. Opportunities for selective mining increase as a deposit becomes more heterogeneous. This leads to an interest in methods for estimating the distribution and characteristics of mineral heterogeneity within the ore-body. The objective of this work is to present some definitions of mineral heterogeneity, and to explore how heterogeneity as defined can be measured and inferred within ore-bodies.CITATION: Hellicar, A, Sennersten, C, Lindley, C and Evans, B, 2018. Heterogeneity assessment for grade engineering in complex ore bodies, in Proceedings Complex Orebodies Conference 2018, pp 11–13 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

The Rum Jungle mine was operated by Territory Enterprises Pty Ltd who mined uranium on behalf of the Australian Government with operations spanning the period from 1953 to the final closure of the mine in 1971. In addition to the extraction of uranium from the open cut pits, copper, manganese and lead were mined and processed at Rum Jungle. During the latter part of the operation, and after the closure of the mine, environmental studies were carried out which were aimed at determining the causes of the pollution at Rum Jungle and identifying a rehabilitation strategy for the mine site. These studies identified sources of heavy metal and acid pollution and proposed a rehabilitation strategy which consisted of 1. recontour, construct impervious covers and controlled surface drainage on, and revegetate three overburden heaps,

Jan 1, 1984

By J Lane, D J. Barker, B Pei

Queensland Alumina Limited (QAL) is the worldÆs largest producer of smelter grade alumina, located in Gladstone, Queensland, Australia. The plant employs evaporative cooling towers for waste heat rejection. Process water requirements include red mud residue disposal, steam venting to the atmosphere and Calcination feed moisture. Raw (untreated) water consumption in 2001 was 37 700 m3/d or 3.8 m3 per tonne of production. The Gladstone region experienced a water shortage in the period 2001 to 2003, resulting in progressive water restrictions. Industry operated under a ten per cent restriction from April 2002 and in November 2002 a 25 per cent restriction came in force. The maximum restriction level of 50 per cent was anticipated for the middle of 2003. Water restrictions of these magnitudes have the potential to result in significant production limitations, which would have major economic consequences for QALÆs owners, customers, suppliers and employees. Therefore it was imperative that measures be found to mitigate the impact of these restrictions. Furthermore, as one of the largest water users in the Gladstone region, QAL had an obligation to the community to minimise water usage as much as possible. A thorough analysis of water usage on site was conducted, focussing on all water streams leaving the plant. The philosophy used was that by minimising water outputs, the inputs would follow suit. Where possible, preference was given to solutions that provided lasting water savings. This occurs when the value of the water saving justifies the project cost, irrespective of water restrictions. By June 2002 an average water saving of 19 per cent was achieved, almost double the required saving. By end November 2002 further projects had increased the total water saving to 29 per cent, mainly through the re-use of GladstoneÆs municipal treated effluent as wash water. Further measures to reach the target of 50 per cent reduction were investigated. The evaporative cooling system was to be replaced with seawater cooling, using cooling towers to minimise the seawater pumping cost. Another benefit of this concept was the ability to dispose of the cooling tower bleed stream with the existing system for neutralised red mud disposal. This would avoid the need for an additional environmental outfall from the plant. In February 2003 the Gladstone region received over 500 mm of rain, which boosted water reserves to five years supply at forecast usage rates. This led to the lifting of all water restriction. As most of the implemented water savings measures are economically viable in the absence of water restrictions, raw water usage at QAL is still less than 75 per cent of pre-2002 levels.

Jan 1, 2003

By A K. Bhatnagar, S Saha, P Dixit, A K. Mukherjee, P Patra

TATA Steel’s R&D Division at Jamshedpur has developed a slime beneficiation process to recover iron values from iron ore slime. This process recovers iron ore concentrate containing 2.2 per cent alumina from a feed containing 7–10 per cent alumina. The reject generated from beneficiation of iron ore slime is treated as waste as the iron content in the reject is below 45 per cent. Effective utilisation of this waste is required for making the iron ore slime beneficiation process a zero-waste technology. In this connection several studies were made towards utilisation of slime waste. One of these studies revealed that slime waste can be used as a soil conditioner. Slime waste contains particles of size less than 10 micron and when these particles are mixed with soil in definite proportions, the porosity and the permeability of the mixture goes down. As a result, the water holding capacity (WHC) improves. This concept was evaluated through a series of tests at greenhouse level to optimise the soil to slime ratio. Finally, a pilot scale field trial was carried out over a period of three months using paddy rice as the crop. Three separate plots with compositions of: soil + organic matter comprising Farmyard Manure (FYM), (ii) soil and slime waste (2:1) + organic matter (FYM), and (iii) soil and slime waste (2:1) + organic matter (FYM) + Nitrogen, Phosphorus and Potassium (NPK) fertiliser were used for the pilot trial. The results showed a 20 per cent increase in the productivity of paddy rice for plot (ii) as compared to plot (i). This was due to the beneficial effect of slime waste in the soil. The addition of inorganic fertiliser such as NPK in the ratio of (4:2:1) further enhanced the productivity of paddy rice.

Sep 18, 2023

AustraliaÆs current interest in renewable energy is based on a desire to reduce the countryÆs greenhouse gas emissions. Wood from sustainable sources offers a unique opportunity to combine greenhouse gas benefits with other significant environmental and social benefits, including salinity mitigation, carbon sequestration, soil replenishment and rural industry. The challenge is to make renewable energy from wood in a cost competitive manner, so that this broad range of benefits may be best realised. Bioenergy and carbon products are of great interest as new, commercial forestry products that can drive large-scale environmental tree planting:In Western Australia, Enecon has worked with Western Power Corporation to build the first full-scale plant for integrated processing of mallee eucalypts, to produce activated carbon, renewable power and eucalyptus oil. It is intended that this plant is the first of a number of such plants to help catalyse environmental tree planting in Western Australia. New technologies being developed overseas may provide competitive bioenergy in areas where traditional markets for wood do not exist. For example, pyrolysis converts wood into a bio-oil that may be transported to remote sites for power generation in gas turbines. Pyrolysis also produces wood char. Pyrolysis and wood-to-ethanol technologies, coupled with short rotation coppicing trees, offer the long-term prospect of large-scale production of renewable fuels around the country.

Jan 1, 2006

By N Setoudeh, A Nosrati, N J. Welham

The current surge of interest in lithium (Li) is due to the anticipated demand for electric vehicles and small scale power storage. Brine deposits contain most of the global Li resource, however hard rock deposits can be more readily and rapidly developed and comprise the majority of proposed projects. These projects plan to use the conventional processing routes of dense medium separation and / or flotation to produce a spodumene concentrate for sale. The standard route for subsequent processing of spodumene concentrate is thermal decrepitation, acid leaching, solution purification and precipitation of lithium carbonate. This is typically followed by further purification. A number of projects have ores which contain other lithium minerals, principally micas, lepidolite and zinnwaldite, necessitating an alternative treatment route. Several different routes for spodumene processing are under development to reduce costs to compete with brine projects. This paper will give an overview of the strengths and weaknesses of the current and alternative processes.CITATION:Welham, N J, Nosrati, A and Setoudeh, N, 2017. Lithium ore processing – an overview of the current and new processes, in Proceedings MetPlant 2017, pp 185–194 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By A Cornelius, P Connor, S Fraser

Iron ore mining is a major source of export income for Australia. However with the decreasing reserves of high-grade, low-phosphorus hematite ore, there is mounting pressure to provide consistent mineralogical ore grade. Enhanced 3D characterisation and modelling are crucial to respond to these exigent requirements. To tackle this problem a revolutionary mine-based, imaging system (based on Visible Near Infrared û Short Wave Infrared reflectance spectroscopy û VNIR-SWIR) has been developed. This innovative, CSIRO-built prototype produces mineralogical maps that will have a major impact on ore grade characterisation. Australian iron ore companies will benefit immensely by pioneering this emerging and unique mining technology. The significance of VNIR-SWIR reflectance spectroscopy is well demonstrated with field portable spectrometers and airborne hyperspectral systems. At the mine-scale level, this newly developed imaging system will allow accurate and objective mineralogical mapping of mine faces and benches with very closely spaced sampling. These spectral mineral maps will improve deposit delineation and bring accurate and objective ore grade characterisation that will minimise drilling and enhance ore recovery. This will in turn lead to cost saving and better long-term block model planning. This system will also improve safety for mine geologists in providing mineralogical information at a distance, avoiding the need for any close contact with the mine face. The mine imaging concept is a logical response to the industry need for automatic and objective tools for sustainable and future mining practices.

Jan 1, 2002

By G N. Musafer, M H. Thompson, R C. Wolff, E Kozan

The most important aspect of modelling a geological variable, such as metal grade, is the spatial correlation. Spatial correlation describes the relationship between realisations of a geological variable sampled at different locations. Any method for spatially modelling such a variable should be capable of accurately estimating the true spatial correlation. Conventional kriged models are the most commonly used in mining for estimating grade or other variables at unsampled locations, and these models use the variogram or covariance function to model the spatial correlations in the process of estimation. However, this usage assumes the relationships of the observations of the variable of interest at nearby locations are only influenced by the vector distance between the locations. This means that these models assume linear spatial correlation of grade. In reality, the relationship with an observation of grade at a nearby location may be influenced by both distance between the locations and the value of the observations (ie non-linear spatial correlation, such as may exist for variables of interest in geometallurgy). Hence this may lead to inaccurate estimation of the ore reserve if a kriged model is used for estimating grade of unsampled locations when non-linear spatial correlation is present. Copula-based methods, which are widely used in financial and actuarial modelling to quantify the non-linear dependence structures, may offer a solution. This method was introduced by Bßrdossy and Li (2008) to geostatistical modelling to quantify the non-linear spatial dependence structure in a groundwater quality measurement network. Their copula-based spatial modelling is applied in this research paper to estimate the grade of 3D blocks. Furthermore, real-world mining data is used to validate this model. These copula-based grade estimates are compared with the results of conventional ordinary and lognormal kriging to present the reliability of this method.CITATION:Musafer, G N, Thompson, M H, Kozan, E and Wolff, R C, 2013. Copula-based spatial modelling of geometallurgical variables, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 239-246 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By R R LARGE

In the past decade mineral deposit models have become an important tool for the exploration geoscientist. By combining genetic theories on the formation of particular deposit styles, with geological, geochemical and geophysical criteria relevant to ore location, it has been possible to more effectively focus exploration effort to the regions and local targets which have the best chance of success. However, such models have their limitations, and must be carefully and critically applied and continually updated as new technical and research information becomes available.

Jan 1, 1992

By B T. Qin, C Zhu, Y W. Jia, Y Lu, F L. Li, Q L. Shi

Air leakage through rock fractures in coal mining is a major cause of coal spontaneous combustion. In order to overcome the deficiency of the existing fire control technology and prevent coal spontaneous combustion by isolating coal from oxygen, the article proposes a novel technology of inorganic solidified foam (ISF) with high expansion to fill fractures effectively. ISF consists of fly ash, cement, setting accelerator, redispersible polymer powder, water and aqueous foam. For preparing homogeneous and stable ISF, a preparation system with a pore type foam generator, a mixer device installed with a hollow shaft and helical blades, air compressor, slush pump and monitoring instruments was developed, and the working principles of key devices were elucidated. Based on a series of experiments on the different ratios of each component material and technological parameters of the preparation system, ISF with a foam expansion ratio of 8~10 and dry density of 250–400 kg/m3 was prepared. The relationship between elastic compressive strength, modulus of elasticity and density was summarised. Based on the injection experiment for fracture of loose coal pile with high temperature, the characteristics of sealing air leakage, compressive strength, thermal insulation, flow and cooling of ISF in the fresh state were investigated, indicating that ISF can effectively cut off the air leakage and cover the coal sample to reduce the temperature in the earlier stage, and ISF can remain stable and not crack. The ISF was applied to Luwa coalmine to seal small coal pillar pressure fractures and loose coal fractures in goaf. After press-casting the ISF in Luwa coalmine, the pressure-difference of inner-outer increased, meaning the effect of external conditions on the pressure-difference decreased, showing that it could plug the air leakage effectively.CITATION:Qin, B T, Shi, Q L, Lu, Y, Zhu, C, Li, F L and Jia, Y W, 2015. The novel technology of inorganic solidified foam with high expansion for preventing coal spontaneous combustion, in Proceedings The Australian Mine Ventilation Conference, pp 121–126 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By R Valenta, J Owen, D Kemp, E Lebre, G Corder

Copper plays an essential role in our society. It is one of the key materials supporting economic growth and human development in emerging economies, for its common use in construction, power generation and transmission. It is also a critical metal for the transition to a low carbon future, particularly for its uses in renewable energy and electric vehicles. As a result, global demand for copper has been increasing steadily and is predicted to continue in the future. The demand-supply gap is currently growing, and new mines will be needed to fill it. This project observes the current pipeline of copper mining projects, which are characterised by technical complexity (lower grades, deeper deposits, complex mineralogy etc.) but also environmental, social and governance (ESG) complexities. A common assumption in the mining industry is that a rise in copper prices will unlock these deposits. However, while most technical complexities are price sensitive and are likely to be overcome in favourable economic conditions, the influence of ESG complexities is more difficult to evaluate. CITATION: Lebre, E, Valenta, R, Kemp, D, Owen, J and Corder, G, 2018. Accounting for social and environmental complexities in mining project developments: the case of copper, in Proceedings Complex Orebodies Conference 2018, pp 39–40 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By J Coveney, A Rich, D Grimsey, J Wood, S Creedy

In 2021, BHP and Metso examined processing of high-MgO nickel sulfide concentrates using Metso’s Ausmelt Top-Submerged-Lance (TSL) technology. Test work was conducted in Metso’s pilot test work facility in Dandenong, Australia to explore operability of the SiO2-FeO-MgO-CaO-NiO slag system across a wide range of compositions, temperatures and bath oxygen potentials. Pilot-scale testing aimed to define slag ‘operability limits’, representing the lowest bath temperature at which stable process and equipment operation could be maintained. This work was supported by FactSage™, version 8.2 (by Thermfact/CRCT and GTT-Technologies) thermodynamic modelling, slag viscosity measurements, physical characterisation of quenched slag samples performed by the University of Queensland and benchmarking of commercial-scale TSL nickel smelting operations. A wide range of slag compositions were examined, with Fe/SiO2 ratios varying from 0.4–1.1, CaO content from 0.8–7.0 wt per cent and MgO content from 6–19 wt per cent. Slag SiO2/MgO ratio, wt per cent CaO and matte grade were found to have the greatest impacts on identified operability limits. Operability limits were found to be influenced by both the solids content in slag and viscosity of the remaining liquid slag phase, with the relative contribution of these parameters heavily influenced by the slag composition. In the majority of trials, limits were defined by a theoretical solids content of 40–50 per cent, however in trials with a low Fe/SiO2 ratio and/or low wt per cent CaO, limits were characterised by a much lower solids content due to the increased effect of the liquid slag viscosity in determining the behaviour of these slags. The test work highlighted inherent flexibility of the Ausmelt TSL process to operate across a wide slag range of slag compositions and recover from process disturbances without an interruption to feeding. The trials also demonstrated the possibility for Ausmelt TSL technology to process concentrates with an Fe/MgO ratio as low as 1.4, which has important implications to the commercial-scale processing of high MgO feeds. Arsenic rejection across the trials was very good, with only 30 per cent of arsenic in the feed inputs reporting to the matte phase. Such high levels of arsenic removal provide the Ausmelt TSL process with a notable advantage over alternative smelting technologies.

Aug 21, 2024

By Kokubu H, Moro-Oka A

Gaseous desulphurization from hot metal- lurgical slags containing sulphur mainly as sulphide and(or) sulphate was measured under `low at four different oxygen pressures. The total gas rate was from 1.7 to 2,8 litre/min. Crushed slag samples weighing 2 to 12 g were used for the experiments. The amount of SO2 gas evolved from samples kept at 15500 was rieasured over tires ranging from 20 to 300 min. The gaseous desulphurization rate of sul- phide sulphur becomes high as the oxygen part- ial pressure is increased, while that of sul- phate sulphur is high under low oxygen pressure. The effect of basicity on the desulphurization rate of sulphide sulphur in oxygen atmospheres is not obvious in the range of basicity from one to three. Changes in the ratio of sulphide to sulphate sulphur during the run in oxygen axe analysed. Desulphurization reactions and the rate controlling steps are discussed. De- sulphurization phenomena can be explained by inte.-¦ucia.l chemical reaction rate control.

Jan 1, 1980

Facies associations in the Okiduse Volcanics, woodlark island, suggest that two major volcanic centres erupted synchronously during the Middle Miocene. These centres are referred to as the Watou Mountain Eruptive Centre and the Uvarakoi Caldera. The Watou Mountain Eruptive Centre, centred on Boganuse Mountain in the Okiduse Range, was a typical, moderate-sized composite volcano (or stratovolcano). The seq-uence is readily divisible into lava (Boganuse lava unit), breccia (Nikuben breccia unit) and epiclastic (Talpas sandstone unit) dominant facies, typical of composite volcanoes. These facies girdle Boganuse Mountain and they are interpreted to represent vent, cone forming and ring plain associat-ions, respectively. These facies indicate a reconstructed volcano of approximately 1,700m height with a basal diameter of 7km. The presence of limited exposures of intrusive associated with the vent facies (Kuike'beimmicrodiorite) suggests that the volcano is only partially dissected. The Uvarakoi Caldera is a felsic volcanic system contrasting with the mafic Watou Mountain centre.

Jan 1, 1994

Two examples of risk assessment and risk management in action are discussed. The first is in a management context in relation to Kingsgate Consolidated LtdÆs Chatree operation in Thailand. Kingsgate has conducted an over-riding risk management program to assess and manage risk across its complete business from the Sydney and Bangkok offices through to the Chatree Mine and the companyÆs exploration group. This example addresses how Kingsgate has applied risk management, particularly to the process operation, and the benefits that have been gained. The second is in an operational context in relation to Minara Resources LtdÆs Murrin Murrin operation in Western Australia. The subject is the methodology and outcomes of a risk assessment across the Murrin Murrin operation specifically to identify and assess risks with potential impacts from $1 M to $7 M. This section of the paper then shows how the outcomes of the risk assessment were integrated into MinaraÆs strategic plan to debottleneck the plant and increase nickel production.

Jan 1, 2004

The Lake Rotokaua sulphur deposit, near Taupo, New Zealand, is a lacustrine sedimentary ore body, 220 acres in area and from 7 ft to 96 ft thick, containing, within the area drilled to date, some 20 million long tons of ore averaging 25% elemental sulphur in unconsolidated tuffaceous diatomaceous clay, overlain by about 120 ft of pumice sand and by the shallow Lake Rotokaua. An additional amount of perhaps 4 million tons of sulphur is regarded as probable in the area remaining to be drilled. Current economic studies cover the problems of mining an unconsolidated water-saturated formation with some residual thermal activity nearby; conservation and restoration after mining in a scenic recreation area; beneficiation of the ore and extraction of high- purity sulphur, principally for fertilizer manufacture. The deposit has additional importance as a pointer to possible further discoveries in the Thermal Region.\

Jan 1, 1971

By Stevens P

The Isa Mine of Mount Isa Mines Limited currently produces 5.4 million tonnes of copper ore and 3.3 million tonnes of silver, lead and zinc ore annually. Of this, 5.1 million tonnes of copper ore and 2.2 million tonnes of silver-lead-zinc ore is produced by sublevel open stoping. This paper summarises the capabilities, operating practices and problems encountered with current production drilling practices used to drill sublevel open stopes at Mount Isa.

Jan 1, 1982