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By J M TORLACH

Learning is an iterative process, and we might reasonably expect that after more than a century of mining during an era of sustained technological development, (following a millenium or two of unrelieved hard physical graft), that the more obvious physical hazards could by now be competently managed. It is perhaps a reflection on the perversity of human nature that we have not fully learned our lessons in this exacting environment, and that worse, we have still too often failed to profit by the experience of those lessons. The more obvious underlying factors which impact on this situation are examined briefly, as a prelude to consideration of some outstanding examples of recurrent problems experienced in recent years. Reasons for the continued existence of sub-standard practices are outlined, with a focus on the human element, and finally proposals for appropriate remedial strategies are summarised. This paper therefore seeks to examine and discuss some of our deficiences and to suggest some directions for the way ahead.

Jan 1, 1992

By S S Solomons

In 1991 the uranium spot market price dropped to approximately US$7/Ib U308, a historical low in real terms and the short-term outlook for the industry in the next five years was grim. At this time the Ranger operation was producing uranium concentrate at its design capacity of approximately 3 000 tonnes/year. The loss of two major long-term contracts owing to price and reduced power utility demand due to excess inventories meant that the company could not match production to sales. Continuance at this production level would have resulted in a rapid buildup of product inventory and the tie-up of significant cash reserves. After analysing various options, an innovative operating strategy was devised such that production and sales were approximately balanced without a significant impact on the unit production cost or a long term effect on the plant or operation. A campaign mining/milling operation commenced and approximately 40 per cent of the workforce were retrenched. Multi-skilling of all employees was a critical aspect of ensuring a successful outcome. This paper examines the strategy and reports on the success of the operation two years after the restructuring exercise was effected in November 1991.

Jan 1, 1994

By S Jahn, M Noel, E M. Rykaart, M Pau

Three soil cover test areas were constructed on waste rock backfilled into the Lichtenberg Pit, near Ronneburg Germany. A fourth, uncovered area was included as a control. Each test area measures 50 m by 65 m, and was constructed using full-scale equipment and construction practices. Extensive material sampling and testing was included as part of the construction. Devices were installed in each plot to monitor meteorology, infiltration, run-off, interflow, soil moisture, soil temperature, and soil pore gases. Boreholes were completed in each area and instrumented for temperature, pressure and pore gas sampling to a depth of approximately 60 m. Data from the monitoring instruments have been collected since July 2000, and have been comprehensively analysed and modelled on two occasions. The paper presents an overview of the test area design and instrumentation and the results of the two comprehensive data reviews. The reliability of the various monitoring methods is discussed and experience with several innovative methods is reviewed. The difficulties encountered in modelling the data set using common soil physical models are discussed.

Jan 1, 2003

By G York

South African gold reserves extend to great depths. However, strategies for the mining of such deposits have changed only slightly over the past number of years. Regional support at depth is currently provided by rock pillars and backfill. Many problems have been experienced with these regional support practices at deeper levels. In this paper several alternative forms of regional support are described which include the use of concrete, the use of back area caving and confinement to strengthen pillars. These new concepts are supported by numerical and laboratory modelling and in situ results.

Jan 1, 1998

By S Hapugoda, J Manuel, E Donskoi, L Lu

Sinter can constitute up to 80–85 per cent of the total ferrous burden in modern blast furnace ironmaking operations. The mineralogy and microstructure of iron ore sinter play an important role in determining its physical and metallurgical properties. As a result, characterisation of sinter phases is a cost-effective and complementary tool to conventional physical and metallurgical testing of iron ore sinter in evaluating and predicting sinter quality. Over the years, CSIRO has developed a scheme for characterising iron ore sinter that classifies primary sinter phases such as unreacted and partially reacted hematite and magnetite, and secondary phases, including prismatic high-temperature silico-ferrite of calcium and alumina (SFCA), microplaty SFCA (SFCA 1), dense SFCA, secondary hematite and magnetite, glass, larnite (dicalcium silicate; Ca2SiO4) and remnant fluxes. Quantification of these phases has traditionally been carried out by manual point counting under a petrographic microscope; however, new technologies based on automated optical image analysis, quantitative X-ray diffraction and scanning electron microscopy are now available for evaluation. In this study, two sinter samples of varying chemistry were prepared and characterised using both point counting and automated optical image analysis. The implication of the results obtained for the performance of different quantification methods is also assessed.CITATION:Hapugoda, S, Lu, L, Donskoi, E and Manuel, J, 2015. Mineralogical quantification of iron ore sinter, in Proceedings Iron Ore 2015, pp 35–44 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

The paper provides an overview of the development and content of APCOM symposia since their inception in 1961. This development is set within the context of the academic environment in which much of the research published at APCOM symposia is conducted. This environment includes rigorous external assessment of research quality at national levels and against international benchmarks, which carries significant consequences for funding and for the continued existence of the academic minerals industry disciplines. Adverse consequences that undermine the academic provision of mining and resource engineering will impact negatively on the minerals industry by reducing the level of research and education resources available to it.The traditional reductionist approach to research is contrasted with the inter-disciplinary approach that is required to address the complex systems problems that the minerals industry will have to address to ensure its technical, economical and environmental sustainability. Such an approach offers a means of raising research profiles, of establishing mutually beneficial academic-industry engagement and provides an opportunity for APCOM to take a lead role in identifying the research and development agenda for the future

Sep 26, 2011

By McKee D. J

Much research is aimed at providing a revolutionary advance in technology that has the potential to render current mining and beneficiation problems obsolete. Such revolutionary advancements have been significant but few in number. Recent history shows that most improvement has been derived from a series of incremental improvements to the many processes that make up mining and beneficiation systems. Management approaches are changing to encourage this 'continuous improvement' and to support its implementation through the formal management of quality. This paper reviews some of the industry's priority R&D project areas and demonstrates that very significant opportunities are available to broaden the focus for improvement from individual processes to include the interaction between mining and mineral beneficiation systems.

Jan 1, 1994

By P Crorkan

Within the framework in which future exploitations for Codelco-Chile Divisi=n El Teniente are situated, regarding the deepening of its reserves and the geotechnical problems that affect their recovery, it becomes strategic to evolve with new variants, which make deep mining possible. Codelco ChileÆs Divisi=n El Teniente is progressing within its long-term planning the exploitation of a sector called Esmeralda, which includes its removal through the gravitational caving method (panel caving). It is planned to use pre-caving, which basically consists of developing and undermining the undercut level, without having developed the infrastructure of the production and transport levels. This is carried out in order to achieve a better redistribution of the stresses, thus obtaining higher quality in the infrastructure development of these levels as well as less risk. The extraction reserves for this area, estimated through the opportunity cost selection criteria, were determined at 348 million tons with an average grade of 1.014 per cent Cu. The project carried out geological and geotechnical studies in order to prevent the geomechanical risks of the sector to be exploited, which is a site conformed totally by primary ore. Lithologically, it occurs mainly in Andesite, located at the western limit by Brecha Braden Pipe. There are also varieties of porphyries and hydrothermal breaches of anhydrite. The Esmeralda Mine production program will increase from 4000 tpd (average) in 1998 to its 45 000 tpd rate of production estimated for the year 2005. The approved investment for the period 1995 to 1999 is $US 150 million, out of a total $US 213 million for the project. At feasibility study level and before the project, it showed a Net Present Value of $US 342 million, an Internal Rate of Return of 37 per cent and an IVAN indicator of 2.3 for a ten per cent discount rate and a copper price of 100 US cents/lb.

Jan 1, 2000

The efficient and profit-maximising daily and long-term management of the Vera Nancy resource depends on decisions based upon assay data. This paper examines the range of sample sources, the methods of sample collection, assay techniques and Quality Assurance used by the mine. The orebody has a relatively low nugget effect for a gold mine (around 25 per cent) and this greatly assists in reducing sampling error and producing reliable assay data for production decision-making. Reconciliation between mine and back-calculated mill grades generally sees the mine under-calling mill grades by around four per cent.

Jan 1, 2000

By D Hunter

A production information management system (PIMS) was recently implemented at Queensland NickelÆs Yabulu Refinery. Although a strong business case was developed to justify the significant investment in PIMS some potential beneficiaries remained sceptical of the anticipated benefits. The decision to install PIMS was justified as the on-line availability of continuous production data enabled the optimisation of some crucial operations resulting in significant cost savings, improved throughput and final product quality. Furthermore the rapid access to extended historical data has allowed the cause of repeated failure of equipment to be determined. The investment is expected to pay for itself within two years and has already contributed towards significant savings. This paper focuses on some of the diverse production improvements gained and compares the anticipated benefits in the business case to those achieved. A brief outline of the phased implementation of the OSIsoft PI data historian and complementary client software at Yabulu is included, along with details of the lessons learned.

Jan 1, 2003

By Pratt V

The economic, social and political environment of the mining and minerals industries is, as we all know, volatile and affected by constantly changing international forces. In addition, the outcome of negotiations with overseas customers is often uncertain for long periods, or even unfavourable. The industries and companies represented at this Conference are in an arena of high competition, risk taking and enormous capital outlay. They are industries which our overseas markets (rightly or wrongly) have criticised for industrial relations problems, unreliable production and uncertain deliveries. They are industries which have an urgent need to be cost effective and competitive at all levels of activity.A critical factor in the mining and metallurgy industries is, therefore, its human resources and its human resource management. It requires the full use of available talent, innovation, skills and qualifications within its workforce, and the appropriate management of these resources.

Jan 1, 1985

In 1984/85 financial year Australia produced 529 thousand barrels per day (kbd) of crude oil. By far the major contribution (453 kbd) was light waxy oil from offshore Gippsland, Victoria. When these discoveries were made in the latter 1960s, imported oil was available in abundant supply and at low prices. Because of this, the Gippsland producers persuaded Government to control the marketing and pricing of their crude, and thus provide the required security of offtake. Political events in the middle East created supply shortages during the 1970s, and dragged up government selling prices for OPEC crude oil. Thus Arab Light crude that sold for less than US$2/barrel (bl) in 1970 reached $34/bl in 1981. Following the consequent decline in world oil demand, in 1982, Australian refiners sought to evade their obligation to lift Gippsland crude. Hence, in 1983, the Government was forced to introduce a floor quota of 385 kbd of Gippsland crude liftings and to allow producers to export any additional production refiners did not require. On expiry of the old arrangements, Government introduced a partial free market from January 1985, whereby the balance in excess of 350 kbd may be sold to Australian refiners at negotiated prices, or exported as before. In 1984/85 exports were some 90 kbd and will be higher in the current year. About half this total has been exported by BHP, providing valuable experience and lessons which are described in the paper.

Jan 1, 1986

By Unver B

Longwall advance mining is still the predaninant system of coal extraction in the U.K., contribiiting to sane 70 % of underground coal production. Gate roadways providing access to a longwall advancing coal face are maintained adjacent to a rib pillar under high strata abutment pressures and the caving rock mass. It is very difficult to realistically model such access roadways using mathematical or numerical techniques and hence, predict roadway closure. For the past 15 years, a research group in Nottingham University has been engaged in the study of longwall gate roadway stability using observation methods. Gate roadway deformations have been measured in 224 gate roadways and a comprehensive data base has been established. The paper describes the statistical analysis of this database and presents sane. predictive equations which will enable a forecast of the gate roadway closure to he made. Further field work to validate these equations. is described together with an error analysis. The results are very promising and indicate that it is possible to predict gate roadway closure in the U.K. within practical limits of Accuracy.

Jan 1, 1986

By J Heyes, T Cooper, M Stimpfl, R Staines, J P. Pearce

Acid and Metalliferous Drainage (AMD) is one of the key risks facing the mining industry worldwide. If not properly managed and/or not identified in a timely manner, AMD has the potential to decrease environmental values for generations to come. Ore extraction generates vast volumes of mineral waste (waste rock and tailings) which are stored in perpetuity at the mine site. Some of these materials are not inert and when in contact with air and water can react, generating poor quality water and compromising operational and closure environmental objectives. Understanding the geochemical behaviour of waste rock and tailings is therefore key to identifying risks and opportunities which support effective mineral waste management strategies across the mining value chain and progress toward an environmentally sustainable future that minimises closure liabilities. To ensure AMD risk is recognised and managed uniformly across its portfolio, BHP developed a Global AMD Management Standard for implementation across all operations, including closed sites. The AMD Management Standard provides a management framework to support the consistent, simple and sustainable global management of AMD risks. This ensures mines are planned and operated to be environmentally smart and modern, geochemical risk management is not an afterthought but a key driver, and environmental sustainability is actively pursued to reduce closure liabilities. The AMD Management Framework, on which the Standard is based, was adapted from industry leading practice guidance, ensuring it applies to multiple regions. The framework also comprises sequential requirements throughout the mining life-cycle. It is an iterative framework with an adaptive management approach that is designed to incorporate new data, information and management opportunities into AMD risk assessments and mine plan revisions.

Jul 1, 2021

By F D Durao, Muge F. H, Rogado J. Q

In the scope of the project named CAPUME II (EEC BRITE/EURAM contract - project MA2M-CT90,-0042(SMA)) for the development of an integrated mine planning system for underground mines, two of the main tasks were the development of a short-term mining planning procedure (module) and a numerical simulator of the mineral processing plant of Pirites Alentejanas - PA. The short-term mining planning module defines the mining sequences by solving a constrained minimisation problem. The ore grade variability is the objective function subject to the geometrical constraints of the mining method and to the maximum of `internal blending'. The optimisation problem is solved by applying a dynamic programming algorithm. The plant simulator is an essential tool of the planning system allowing the preview of metal grades/recoveries of copper, lead and zinc of concentrates streams, given the corresponding metal assays of the run-of-mine ore, defined by the short-term mine planning module. This way, the management can plan the short-term mining operations (the weekly sequence of exploration blocks and the internal planning) in order to fulfill given required conditions, based on a shipment schedule and on a purchaser's formula. In this paper, after a short description of the short-term mining planning module and of the simulation package named SIMUL, a synthesis of the main model development steps and the results of some simulation runs are presented and discussed.

Jan 1, 1995

By J E. Moffatt, N A. Spooner, T J. de Prinse, D J. Ottaway, E Klantsataya, L d. S Teixeira, B W. Smith, T B. Payten, G Tsiminis

Single wavelength fluorescence sensing has been used in the preconcentration of ores for many years in situations where it is typically specific to the mineral of interest. Examples of fluorescence sensing include the sorting of diamonds in diamond mines and the sorting of scheelite in tungsten ores. However, the number of minerals that show useful single wavelength fluorescence properties in the visible spectrum is relatively small, so the application of fluorescence sensing is currently limited to niche application in the minerals industry. Recent developments at the University of Adelaide have focussed upon extending fluorescence signal measurements into the infrared spectrum, as well as investigating multi-wavelength fluorescence known as up-conversion fluorescence. These techniques may not only significantly increase the number of minerals that exhibit fluorescence properties suitable for both identification and sensor-based sorting, but also provide mineral-specific signatures of higher quality than previously attainable. This paper details the research work carried out by the University of Adelaide and funded by CRC ORE to develop a mineral-specific fluorescence sensor. The sensor targets two fluorine bearing minerals, fluorite and fluorapatite, that are common in many base metal ores such as porphyry copper ores and silver/lead/zinc ores. Fluorine is a known penalty element in mineral products derived from these ores, so mining companies need to monitor and control the amount of fluorine in their final product to keep it below commercially agreed specifications. Currently there is no real time sensor capable of monitoring fluorine in the ore feed so monitoring and control is carried out using time-consuming standard sampling and off-line laboratory measurements. The development and application of a real time fluorine sensor will enable the mining companies to monitor and control fluorine levels in the plant, greatly reducing the time and cost associated with producing their mineral concentrates within the prescribed specifications.

Nov 10, 2020

By A J. Minns

This paper addresses the question: how can the minerals industry remain viable; viable in the sense that we are able to access land for exploration and discovery, we are able to develop and operate mines (and processing plants) safely and profitably and we are able to close operations in a responsible manner, so that modified landscapes are restored to acceptable community standards?Many of the answers to this question can be addressed through the theme of this conference û that of eco-efficiency. The eco-efficiency concept is very useful, since it does help to translate principles of sustainability into business value at the operational level. To provide some context to how this can be achieved, the paper discusses what is happening at the international level, outlines some key industry initiatives within Australia and then discusses what work is being done within companies.

Jan 1, 2004

By R W. Henley, L Knuefing, M Turner, Y Zhang, M Saadatfar, A Limaye, R Cruikshank, M A. Knackstedt, A Kingston, L Beeching, N Francois

A better understanding of ore fragmentation and the textural features of ore is a key to the energy efficient extraction of targeted minerals from low-grade ore deposits. In this study, X-ray microcomputed tomography (micro-CT) is employed to study mineral liberation during the tensile failure and onset of fragmentation of a copper ore. Our results show that X-ray micro-CT could inform new studies of ore micromechanics and fragmentation at the laboratory scale and may offer new avenues to address current challenges in the design of efficient comminution processes. We present the results of experiments based on a high-pressure apparatus enabling micromechanical studies to be carried out in situ (inside a micro-CT scanner). This platform produces high-quality 3D images of the evolution of a sample of porphyry copper ore during an in situ fragmentation test. A sequence of tomographic images enables mapping in 3D of both the deformation of mineral phases and the fragmentation process. The fragmentation occurs quasistatically through multiple stages starting with an initial tensile fracture splitting the ore diametrically, followed by tensile-activated nucleation and growth of multiple fractures producing a complex fracture network. Coupling breakage with microstructural information enables quantitative determination of the impact of ore texture heterogeneity on fracture patterns and mineral liberation. This microstructural information can be compared to key measurements of the ore mechanical behaviour such as the global deformation energy, strain deformation field and the stress relaxation response. The latter allows one to identify interesting precursor signals of the tensile failure. The copper liberation, fragment size distribution and breakage patterns are statistically characterised and related to comminution mechanisms which are clearly identified in the sequence of tomographic images. The two dominant mechanisms are rock-rock friction/compression induced by fracture closing and compression-driven fragmentation at rock-crusher contact points.

Aug 24, 2022

Responsibility for the administration of mineral resources is divided between federal and provincial governments. The paper traces the evolution of mineral policies at both levels of government, from the end of World War II to the present. In the immediate post-World War II years, the emphasis was on supplying the raw material needs of a rapidly growing world economy. Policies favouring growth and development of the Canadian mining industry were instituted during this period. Two decades of uninterrupted expansion (the 1950s and 1960s) ensued. The decade of the 1970s was a turbulent one for Canadian mineral producers. Governments intervened more substantially than ever before. Moreover, the industry suffered from an intense period of competition for resource revenues by the two levels of government. At the same time, far reaching changes were taking place in the structure of world mineral markets. To date in the 1980s, the mineral industry has, perforce, adapted to existing mineral market structures. Mineral policies, too, have shown signs of adapting to the needs of the mineral industry. Whether the resulting mix of policies will permit the revitalization of the Canadian mining sector remains to be seen.

Jan 1, 1986

The region we call the West Coast is acknowledged as one of the richest and most diverse mineral provinces in the world. It's the most rugged part of Tasmania and our island is one of the most rugged parts of Australia, so that speaks for itself. A hostile land of razorback mountains, deep ravines, dangerous rivers, almost impenetrable rainforests and a climate that can change from mild to freezing in a matter of hours.

Jan 1, 1993