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The current quantity of rejects from coal beneficiation in Australia represents 20 to 25% of raw black coal production. Approximately 80% of the rejects are derived from coarse processing for particles in the 200mm to 0.5mm size range. The safe and enviornmentally acceptable storage of coarse coal rejects is of interest to coal mining companies. Additional public benefit would be derived from the utilisation of a waste product as a source of fill material for civil and mining engineering applications. BHP Engineering has taken a leading role in the design for storage and utilisation of coarse rejects from two mines associated with the Broken Hill Proprietary Conipany Ltd. The tailings dam at Stockton Borehole Colliery (N.S.W.) is to be raised and a study by BHP Engineering has shown that coarse rejects are suitable for the formation of the supporting embankment surrounding a compacted clay core. Transportation and storage of coarse rejects at the Thiess Dampier Mitsui Riverside Mine (Moranbah, Qld) is achieved by a conveyor leading directly from the coal preparation plant to a discharge stacker on the crest of the rejects stockpile. Production of coarse rejects was higher than anticipated for the initial dump design. BHP Engineering has completed a review of dump design with emphasis on safe operating conditions for the conveyors and stacker system. Data on the geotechnical properties of coarse rejects from Australian coal mines are presented. Coarse coal rejects are a material which should not be considered as waste, but as a potentially valuable resource for many future applications. Appropriate engineering design for the storage and utilisation of coarse rejects would result in an improved environment and economic benefits for the Community.

Jan 1, 1987

By C E. Loayza, R M. Pinto, J G. G=mez

The Yanacocha District is located 20 km north of the city of Cajamarca, in the Northern Andean Orogenic belt of northern Peru.Gold production may have occurred as early as Incan times (Paverd, 2000), but modern exploration that began in the 1960s targeted only copper and silver. Newmont Mining Corporation, BRGM and Compa±fa de Minas Buenaventura began exploring for gold in 1983, with Newmont as operator.Initial drilling took place in 1985. By 1992 a reserve of 1.28 million ounces was reported (Teal et al, 2002).Production began at the Carachugo deposit in 1993.Current reserves are 31.7 million ounces at $US 325 per ounce at a grade of 1.03 ppm (Newmont Annual Report, 2003).The operating company, Mineral Yanacocha SRL (Newmont 51 per cent, Buenaventura 44 per cent and International Finance Corporation five per cent) produced 2.85 million ounces in 2003, making Yanacocha one of the largest gold mining operations in the world. The district is made up of a series of epithermal, high sulfidation style gold deposits and one gold-rich gravel deposit (La Quinua), aligned in a NE trend.La Quinua is not discussed in detail in this paper. The bedrock deposits are hosted in a Miocene volcanic package, the Yanacocha Volcanic Complex that also trends NE.Re gional NW striking Andean faults intersect the NE striking Trans-Andean Chicama-Yanacocha structural corridor (Turner, 1997), localising the district mineralisation. These two structural orientations dominate the district, controlling breccia and intrusion locations, and gold mineralisation. Discontinuous EW oriented fracture zones are interpreted as extensional and locally are important in controlling gold mineralisation.

Jan 1, 2004

The microstructures exhibited by ilmenite in its association with other oxide minerals have been the subject of a number of papers, the most comprehensive of which is that by Ramdohr. The following observations in some degree extend his conclusions. They are based upon a study of about sixty specimens of "massive" ilmenite and titaniferous ores from a number of wIdely 'scattered Australian localities. Specimens of this character proved much rarer than was expected. The collection was gathered together through the generous aid of the University Geological Departments, Geological Surveys, and Natural History Museums of the several States of the Commonwealth, all of which contributed such specimens of local origin, as they possessed. Special thanks are due to Dr. E. S. Simpson, of Western Australia, who made available several highly interesting specimens, together with his...

Jan 1, 1938

By D Woolmer

Since January 2019, BHP Olympic Dam have been trialling the use of a drone based LiDAR mapping system for the purpose for surveying stope voids. This new technology utilises Simultaneous Location and Mapping (SLAM) algorithm providing positioning, stability and collision avoidance in GPS denied environments. Implementation of this system utilised underground personnel trained in the equipment’s use. The study’s intention was to evaluate the effectiveness of this equipment versus traditional surveying methods in regards to quality, safety and productivity. The trial results showed a marked improvement in the quality, productivity and personnel safety when conducting surveys. The use of the drone and LiDAR system reduced personnel and equipment requirements for surveys, thus allowing these resources to be deployed elsewhere. The technology’s simple and rapid deployment allowed multiple surveys to be conducted during a 12 hour shift, including ad-hoc work with minimal disruption to underground operations. After the drone’s initial trial, further work was conducted to utilise the Hovermap LiDAR scanner on other platforms to increase utilisation. A mounting system was created allowing the LiDAR to be mounted on a remotely operated loader or vehicle. This enabled drawpoint scans to be taken directly after production completion, resulting in faster stope close outs and drive scans for convergence monitoring. Implementation of the LiDAR system has resulted in improvements in the stope production cycle by reducing delays previously associated with data capture. The increase in the volume and quality of data has also allowed in-depth back-analysis of stopes in new mining areas to be conducted, which have driven improvements in the design process.

Mar 15, 2021

By É Lèbre, G Corder

The circular economy concept, as defined by the Ellen MacArthur Foundation (2015) and quoted by the recent International Council on Mining and Metals (ICMM) Guide to Responsible Sourcing, calls for shifting industrial systems from a linear take-make-waste model to a circular model (ICMM, 2015). In this model products are designed to optimise product and material recovery and reuse, and by-products of one system are used as inputs into other product systems. While the mining industry to date has made a limited contribution to the circular economy, the current market conditions, which are prompting calls for greater innovation, make the timing right for the industry to boost its contribution by utilising and generating value from mining waste, or making it available as a feedstock from which other industries can harness value.The first part of this extended abstract discusses the way the circular economy concept can be adapted to metal mining activities, contributing to a more sustainable resource extraction at the mine site level. The second part of this extended abstract presents a circular economy based framework revolving around non-renewable resources conservation. The third and final part examines the application of the framework to the Mount Morgan mine in Central Queensland.CITATION:Lèbre, É and Corder, G, 2016. Utilising mineralised mining waste – contributions to the circular economy, in Proceedings Life-of-Mine 2016 Conference, pp 132–134 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By F Ramos

Conventional techniques for resource estimation generally involve the laborious analysis of variograms and the specification of parameters for covariance functions. In large deposits, construction of resource models and their update require significant amount of manual work, expert knowledge and time. In this paper we take a machine learning view to the problem of resource estimation. This is a non-parametric Bayesian method, leading to automatic parameter estimation (learning). Through Bayesian learning, the parameters of the model can be obtained by optimising a quantity known as the marginal likelihood. The main advantage of this approach over conventional maximum likelihood estimators is that the objective function incorporates the OccamÆs razor principle. This allows the comparison of different statistical models û for example, models designed with different covariance functions û and naturally penalises complexity, thus avoiding overfitting. Our technique presents significant flexibility for the definition of mean and covariance functions and permits the usage of more sophisticated models.The second contribution of this work is the formulation of a data fusion mechanism that continuously updates the resource model. As mining progresses, more information becomes available. For example, the hardness of the rocks can be measured while drilling blast holes, grades of ore and contaminants are obtained from cone logging. This information is in general available at a finer spatial resolution but can be more uncertain. The data fusion mechanism can seamlessly estimate the uncertainties of the different types of information and fuse them as new measurements are acquired. This procedure can significantly improve the quality of the resource model, defining new grounds for stochastic mine planning. We demonstrate the effectiveness of our approach in estimating iron ore deposits by integrating information about different grades.

Sep 26, 2011

A hidden asset in most exploration and mining activities is data. Common practice involves the spending of large amounts of money to discover, define and prove the viability of a mining project. Some organisations have used operations research analysis and internal costing methods to allocate a value to their data and to compare the costs of data maintenance to other more tangible activities like plant and equipment maintenance. Those organisations, which do not undertake such an analysis often, have little knowledge or understanding of the extent and the worth of their data. Often the organisations lack of knowledge and understanding of the data is indicated by their failure to fully exploit or realise their opportunities. The focus of this paper is to discuss new technologies that optimise the management and security of collected and derived data. The technologies discussed are components of the software systems acQuire and MineSight.

Jan 1, 1999

By M Parcell

"Ventilation risks in an underground mine have essentially remained the same for centuries, yet theevidence suggests that there are many coal mines that have failed to adequately control these risks.The conduit for the knowledge learned by previous generations exists in the mining legislation. In an ideal world, mines would not need legislation to tell them what to do; they would resolve the risks to an acceptable level so as to protect the safety of persons in the mines based on the acquired knowledge. There will be some who have been personally aff ected by a mining disaster but for the majority they will be remembered as a vague recollection of an event from long ago. The mining legislation is the repository for the knowledge and outcomes from inquiries of past disasters. The challenge for the current generation, and the generations to come is to appreciate the legislation that exists, so as to not ælearn the hard wayÆ. In reviewing most disasters there is comment or discussion on the adequacy of the legislation, which ultimately results in some amendment to the law. For each person, there is an increasing responsibility to ensure that the same mistakes are not repeated. Understanding the legislation, its history and its purpose is the fi rst step in ensuring thatventilation risks are eff ectively managed. Failing to do this will be disastrous. This paper discussesthe relevance, importance and potential pitfalls of coal mine ventilation regulation."

Jun 1, 2012

The cost of production from truck and loader fleets is influenced by management development of the culture of the organisation, work practices, systems and procedures of the production and maintenance teams. Establishing if the cost of production is the best that can be achieved then requires the measurement of results against established standards of performance. This paper provides a series of discussion points of the factors that influence the cost of production from men and machines for large scale open pit mining operation and provides some suggested performance standards in the form of Benchmarks. Most of the references have been drawn from established large scale deep pit mines in USA, Canada and Australia which have had to implement and constantly fine tune cost efficiencies in order to survive. The discussion provides:ò a review of priorities or the relative importance of the various cost elements for a mining system;ò suggestions of systems and procedures for the operation and maintenance of machines which are considered to yield the best overall results;ò examples of operations that have developed and implemented management systems and controls that are achieving good results in specific functions; andò suggested benchmarks of performance.

Jan 1, 1992

Since the mid-1970s there has been increasing attention in the South Pacific area to the problems of disaster planning and management at various levels, mainly from regional through national to provincial levels. This concern has been expressed in a variety of ways. International aid donors have made their views known in commentaries or reports. Seminar discussions have been organised at the regional level (such as at Suva, 1976; Suva, 1979; Tonga, 1982 and Suva, 1983). In-country training workshops or meetings have been organised (such as the "Disaster Preparedness Workshops for Non-governmental Organisations" in Pacific countries, jointly run by the Australian Red Cross and the Australian Overseas Disaster Response Organisation and supported by AIDAB, in Vanuatu, 1985; Solomon Islands, 1985; Western Samoa, 1986; Fiji, 1987; Tonga, 1987; Lae and Port Moresby, Papua New Guinea, 1988) or held outside the area (ACDC at Macedon, 1981). Training and/or research institutions have been established such as the East-West Center, Honolulu, and the Asian Disaster Preparedness Center, Bangkok (more Asia oriented). As part of the East-West Center Pacific Islands Development Program's Disaster Preparedness Project, a detailed manual of disaster preparedness and response procedures and guidelines has been published (Carter, 1984).Table 1 and figure 1 show that the area with which this discussion deals is a highly fragmented island region, comprising many small, some minute, nations, both in land area and population. The social structure is predominantly rural, with the capital city often making up a small part of the total population and, in absolute terms, little more than a small town. Outside the administrative and governmental activities concentrated in the capitals, in most cases the indigenous inhabitants depend on subsistence agriculture or on usually a monocultural concentration on a cash crop, most frequently coconuts.

Jan 1, 1990

By J S. Moema, R Paton, J Zimba

Today, most organisations are familiar with the pressure to increase their effectiveness and efficiency, regardless of the nature of their business. Cost cutting and increased productivity are the main themes of many initiatives to ensure the profitability of operations and, ultimately, shareholder satisfaction. It is well known that the cost of comminution to liberate minerals such as gold from their respective ores is a major expense for mines. Comminution costs consist predominantly of grinding balls and electricity. However, there are no national or international standard specifications for grinding balls û on which a single mine may spend several million dollars per month. In addition, in the past mines generally did not specify the minimum requirements when purchasing grinding balls from suppliers. The result is that every supplier has its own grinding ball recipe (regarding chemistry and heat treatment), and is under no pressure to implement a quality assurance plan to ensure that a consistent product is delivered. The resulting variation in the quality of grinding balls leads to increased steel consumption rates and hence increased milling costs. A more stringent quality plan will generally not be welcomed by suppliers since this may entail further investments and/or reduce the production rate. In a sense, suppliers benefit from poor quality grinding balls as this leads to increased sales. Perhaps the main problem is a lack of understanding of the factors that influence grinding ball performance. This paper will describe the factors that influence the wear rate of grinding balls from both a microstructural perspective and a mill perspective. In addition, some insights are provided on the different grinding balls available and ways that users can verify their quality.

Jan 1, 2007

By D Connelly

Quartz deposits are common in nature but the presence of quartz suitable for yielding high purity quartz is exceedingly rare. This paper describes a test work study on producing high purity quartz (HPQ) product to meet the tight product specifications of greater than 99.97per cent, including four and even five nines, for uses including, lighting and fibre optics and modern-day high efficiency solar panels. Due to demand in renewable energy applications the market for high purity silica solar panels known for their increasing efficiency and durability is rapidly growing. Demand continues to rise for the use of high purity quartz in semiconductors, electronics, imaging and sensor markets. Microelectronic components are created by chemically fabricating wafers of semiconductors such as silicon to obtain the desired transport of electrical charge and control of the current. The production of silicon metal from high purity quartz has been designated a Strategic Mineral by the European Commission and by the US Department of Justice due to the growing significance of this metal in various industries. The subsequent processing of quartz is the key step to adding value and aiding technological advances. Overall, the high purity quartz market is a highly secretive, specialised market with increasing opportunities for stakeholders. The attempt to produce HPQ in this work was carried out using an Australian quartz ore following a typical HPQ process flow sheet. The unit processes included primary crushing, scrubbing, magnetic separation, flotation, acid leaching followed by hot chlorination. The results indicate that grinding of quartz requires specialist equipment due to the hardness and extreme abrasiveness of the ore leading to additional iron contamination in the ground ore. The critical impurities were aluminium, iron, sodium, potassium, lithium, titanium, zircon, calcium and magnesium. The chemical refining was found effective. The hot chlorination process needed to be done at 1200°C in a chlorine – hydrogen chloride gas atmosphere. The risk of any gas being released during this stage is very serious and only specialist companies should and can carry out this step. More recent studies reported many new options that appear to facilitate the production of HPQ with the requisite purities more easily, but costly equipment along with highly trained operators are required and hence unlikely to become available in standard metallurgical laboratories any time soon.

Sep 1, 2024

The 1980's have produced an outstanding revival of the Australian gold industry. In contrast to some previous mining booms, the economic aspects of the growth in gold production are soundly based. In general the new developments have been highly profitable and this is beneficial to all parties- whether they be government, shareholders employees or suppliers. Mining companies are showing a large commitment to gold exploration with approximately 50% of Australian exploration budgets now being directed towards gold. An increasing proportion of this expenditure is being channelled towards the eastern States with Queensland 'being the major centre of interest. Further strong growth in production is expected with some 50 projects likely to come on stream before 1990. A very significant aspect of the foundation for this growth is a continuation of the existing tax status of the industry.

Jan 1, 1987

By J Boshoff, D Reid

It has been recognised worldwide that the liquefaction risk of unconstrained tailings stacks or cyclone underflow embankments requires careful consideration. The stability of a tailings deposit where the perimeter embankments are made up of hydraulic fill is often governed by post-liquefaction stability.Cyclones are frequently used around the world to classify tailings into a coarse underflow for building a tailings impoundment wall and a finer fraction that is disposed of into the basin. The shear strength of the tailings that form the outer embankment of a tailings storage facility (TSF) and the location of the phreatic surface are the two most significant factors influencing the structural integrity of the facility. The coarse underflow is placed in such a way as to contain the overflow, which is finer, has low strength and is often poorly consolidated.A cyclone field trial was undertaken at a gold mine in Western Australia to assess the feasibility of using the cyclone deposition method to optimise and increase the capacity of an existing tailings cell. The aim of the cyclone trial was to collect information to demonstrate to the client and the regulators that cyclone deposition was a feasible option for raising TSF embankments. The cyclone trial provided an opportunity to assess the cyclone under field conditions and the quantity and quality of the underflow fraction produced on-site. A variety of methods were used to assess the flow liquefaction susceptibility of the tailings underflow sample produced during the cyclone field trial.The field trial, laboratory testing and analysis will be discussed in this paper.CITATION:Boshoff, J and Reid, D, 2015. The resistance of cyclone underflow material to flow liquefaction, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 151–156 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

The activiltion of sphalerite with electrolytically generated copper ions from a copper electrode instead of the usual practice of the addition of copper sulphate was studied in the laboratory. A large surface area of copper was provided by lining three sides of a bench flotation cell with copper sheeting. The lining was connected to the positive terminal of a low voltage d.c. source, and the cell impeller to the negative terminal.Sphalerite was effectively activated by this arrangement and was subsequently floated using xanthate as the collector.Flotation results comparable to those obtained with 1 lb/ton CuS04.5H20 (0,255 lb/ton copper) were obtained using 0·1062 lb/ton of electrolytic copper and 0·488 kWh of electrical energy. The wastage of copper due to the formation of insoluble precipitates was found to be dependent on the length of time the current was passed. Maximum current was passed for the shortest time to minimize wastage.

Jan 1, 1973

By M Akop, G Phillips, L Elliott

An estimation geologist has many tools in their kit and using the correct one for the job is vital for creating a useful model. Reconciliation is a key step to monitor the performance of a resource model and to ensure the correct tools have been selected and appropriate parameters are set. This paper presents an example of refining the estimation methodology for a Channel Iron Deposit (CID), resulting in an improved model. Rio Tinto Iron Ore (RTIO) CIDs are unique iron ore deposits located in the Pilbara region of Western Australia and contribute a significant volume to the world’s seaborne iron ore market. A problematic feature of these deposits is the irregular dispersion of clay pods that cannot be delineated with confidence within the resolution of the exploration drilling. Resource to grade control reconciliation showed an over-prediction of high-grade material in the resource model. A fresh approach was required to improve grade and tonnage predictions. Historically, clay pods were delineated using traditional wireframing techniques and estimated using ordinary kriging with hard boundaries. The new method utilised indicator kriging to estimate the probability of clay. Probabilities generated from the indicator kriging estimate were used as an additional weighting following the ordinary kriging of grades. Results showed indicator kriging improved global high-grade tonnes reconciliation, however, as expected, it did not improve the spatial prediction of clay. Based on improved reconciliation results indicator kriging has now been adopted as a suitable alternative for analogous CIDs at RTIO. These improvements benefit the mine planning process, but do not replace grade control models.

Mar 22, 2022

This paper describes the MillMapper technology developed for condition monitoring of liners and other operational parameters in grinding mills used for mineral comminution, by presenting a case study of its application. MillMapper provides maintenance engineers, operations managers and process and plant metallurgists with quantitative, accurate and reliable condition monitoring data for informed decision making regarding the maintenance and metallurgical aspects of such mills. MillMapper uses calibrated laser scanners for the capture of three-dimensional surface representations inside a mill during a shutdown so as to determine shell, feed and discharge liner thickness at a resolution of several million data points, a procedure that nominally takes five minutes to complete. Once several data sets over time have been collected inside a mill, MillMapper can be used for liner wear, liner wear zone, liner weight, ball charge volume, ball charge weight and intelligent profile tracking over time. Liner tracking in combination with site defined reline and failure criteria and with throughput tonnage data is utilised for change out prediction of each separate liner segment type.

Jan 1, 2008

By M Battersby, F Parra, S Sanchez-Pino

Pneumatic flotation, as developed by Dr Rainer Imhof, has been applied in commercial beneficiation operations since 1987. Over 85 flotation cells have been installed in more than 30 operations, successfully beneficiating a wide range of minerals. Pneumatic flotation is however still considered as a non-conventional flotation process. Due to its highly selective nature in operation it has generally found its market in difficult applications where conventional flotation equipment has struggled. Compa±fa Minera Huasco (CMH) operates an iron ore pellet plant in central Chile. CMH desired to produce a low silica pellet for the export market where the SiO2 grade should not exceed 1.5 per cent. It is common practice in other countries to float quartz from hematite with relative ease. However, the silicates contained in the magnetite ore of CMH are only present as quartz in small quantities and the major undesirable silicates are difficult to float. CMH spent considerable time on developing a reverse flotation process and a reagent suite to try and reduce the silica content to acceptable levels. However, extensive laboratory and pilot plant tests with conventional mechanical tank type cells and with column cells failed to produce the required reduction in impurities. A series of tests with pneumatic flotation cells indicated that this type of flotation technology could achieve the required silica target. A 500 tph Imhoflot pneumatic flotation plant was subsequently constructed and successfully commissioned by CMH, making it one of the largest iron ore flotation plants in the world. This paper details the background and testing that was undertaken by CMH which led them to choose pneumatic flotation as the preferred process and compares the test results with that achieved in the industrial plant.

Jan 1, 2005

By M Scoble, R A. Hall

The mining industry has aggressively sought competitiveness through increased productivity and return on investment. A primary strategy has been the pursuit of economies of scale. This has also been dependent upon the implementation of new technology and systems integration. System integration has been accomplished through the implementation of mine dispatch, global positioning and mine wide communication technologies. These technologies have tended to advance at different rates of development and implementation. The result has been that across the industry, and even within companies, mines are at various stages of operational system re-engineering in these areas, driven by improvements in productivity and operational efficiency. Although this strategy has been successful, little effort has been made to analyse change in operational performance in order to understand and model the effects of scale in a quantitative manner. This paper considers the particular impact of equipment scale, together with potential future trends. It then presents and demonstrates a preliminary method to quantify through simulation the anticipated benefits of economies of scale.

Jan 1, 2003

By Butters S. E, Deslandes J. V

The selection of loading and haulage equipment in a proposed or oper- ating mine is vital in ensuring the cost effective achievement of produc- tion targets. To assist in the evaluation of different haulage systems, a truck haulage simulation model has been developed at BHP Melbourne Research Laboratories. The operation of the model is described and exam- ples of an actual application at Mt. Whaleback Mine is presented.

Jan 1, 1989