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By D Tuazon, M Powell, M Ziemski, G D. Corder

Although mining companies have made broad corporate-level commitments to adopt sustainability, there continue to be problems when attempts are made to adopt higher-level sustainability aspirations and translate them into appropriate targets and methods at the more-specific operational level. The integration of sustainability principles into minerals processing operational decision-making processes has unique challenges that are not addressed adequately by current tools and methodologies, yet impacts from operational decisions can have longer-term effects realised at closure and rehabilitation.This paper describes a proposed methodology to achieve the integration of sustainability at the operational level through a systematic and rigorous process of identifying and qualifying sustainability issues and opportunities in an operation. The methodology, starting from a sustainability point of view rather than an operational one, guides the identification of process issues and opportunities by examining the operation, unit-by-unit, similar to a Hazard and Operability (HAZOP) process. Each issue or opportunity is qualified according to its measurability, scopes of impact and consequences so that it may be understood fully and the correct engineering problems are formed. Through improved decision-making to account for broader sustainability factors, operations can better address environmental and social expectations and pressures (both corporate and community, as well as immediate and in the longer-term), whilst still delivering on operational and business goals.The methodology has been tested with two case studies at minerals processing operations. At one site, the methodology identified a dust issue which had considerable business risks (loss of valuable product) compared to conventional engineering analysis processes. The other site also benefited from using the methodology as an opportunity to improve the operation of the milling and flotation circuits was identified. The opportunity not only showed a potential to improve operational efficiency, but also potential improvements in water and energy efficiency and a resulting increased resilience against water and energy supply risks. It was important to utilise the holistic approach of the methodology in the identification of opportunities at this site; the goals of the operation showed a strong coupling between water and energy issues which would be difficult to overcome using the operationÆs current organisational model, which deals with such issues separately of each other.CITATION:Tuazon, D, Corder, G D, Powell, M and Ziemski, M, 2012. A practical and rigorous approach for integrating sustainability principles into decision-making processes at minerals processing operations, in Proceedings Life-of-Mine 2012 , pp 233-242 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By B Zhao

Gas and coal dust, as potential harmful elements (PHEs) produced during mining, are considered two serious threats to the safe mining and the health of miners because of its explosive and pathogenic properties. To solve this problem, compound reagents enhanced water spraying technology was used to control the gas and coal dust in excavation working face in this study, and spray testing platform and wind tunnel were used to investigated the suppression effect for gas and coal dust. In addition, sink test, and agglomeration experiments were also used to analyse its suppression mechanism. Testing results show that the dust reduction efficiencies of compound reagents enhanced water spraying technology for four different particle sizes were 80 per cent, 91.43 per cent, 94.74 per cent and 94.46 per cent, and improved by 14 per cent, 10.86 per cent, 8.42 per cent and 4.25 per cent compared to water spraying. Moreover, the gas suppression efficiency also can be increased more than 20 per cent. Sink test, and agglomeration experiments results show that compound reagent improves the spreading efficiency of the liquid on the surface of the coal by changing its wettability, and this process can not only slow down the desorption rate of gas by forming a water-sealing effect in the coal surface indicated, but also promote the agglomeration of fine-grained coal dust.

Oct 12, 2022

By D E. Tennant

In the fields of geotechnical engineering and slope management, various software packages are used to assess the behaviour or propensity for a slope to fail. Traditional kinematic analysis calculates the probability of failure of design sectors with respect to dominant structural set orientations. A novel methodology is provided here to view potential hazardous slope behaviour in 3D, allowing engineers to make informed decisions regarding various pit slope geometries. Apparent dips are calculated for every point in space with respect to every slope orientation of the entire pit surface/design, specifically in reference to bench and inter-ramp planar failure mechanisms. Implementing a proactive approach to slope design will not only lead to early mitigation of risk but can also add direct value by enhancing or improving upon slope angles for earlier access to ore. From a safety perspective, identification of unfavourably oriented slope geometries can be dealt with before failure occurs. This methodology relies on a strong understanding of the existing rock mass anisotropy, particularly behind the face, thereby removing some of the uncertainty surrounding pit design as well as presenting engineers with an additional means to manage risk.

Nov 29, 2022

By Grobler H. P, Chitombo G. R

Production blasting of Dc Beers Consolidated Mines Limited, Koffiefontein and Finsch Mines involves both uphole trough rings of 9 to I I holes and near vertical 360 degree compound rings of 42-54 holes. The rate of production from these stages is dependent upon being able to achieve a specified fragmentation size range and this has driven the derivation of blasting practices to consistently achieve this target fragmentation. At the Dutoitspan Mine, in Kimberley, where mining of the kimberlite pipe is by block caving, 100 per cent extraction of the undercut level by ring blasting is essential. If this is not achieved, pillars are formed which not only inhibit the efficient initiation of the caving process, but also concentrates load onto the extraction level, causing damage to draw points and pillars. These two case studies demonstrate the importance of achieving optimum blasting performance for downstream mining efficiency; ie fragmentation for increased productivity at Koffiefontein Mine and 100 per cent undercut extraction for efficient initiation of the caving process at the Dutoitspan Mine. The case studies also serve to highlight the long road towards blast optimisation taken by De Beers Consolidated Mines Ltd (Koffiefontein. Finsch, Premier and Kimberley Mines) since 1989.

Jan 1, 1995

By C Fricke, R Wood, P Velletri

"In a climate characterised by an ever increasing focus on cost reduction and maximising the utilisation of existing assets and infrastructure, understanding the uncertainty associated with alternative investment and operational choices becomes paramount to minimising the risk of making an ineffective decision. To assist in this process, TSG Consulting has developed an analytic framework to capture the underlying complexity of a mineral supply chain, and then quantify the impact of the uncertainty associated with the key drivers of business productivity. The technical basis of this approach follows three distinct steps: analyse the current system and identify the major factors that drive value build detailed models that can measure the response of the system to potential changes in the factors identified quantify the sensitivity of financial and capacity forecasts to these factors.Each of the above steps draws on a different area from the field of applied analytics, namely: data analytics dynamic modelling and designed experimentation meta-modelling and optimisation.Following the three-step approach described above ensures a rigorous modelling and analysis process is executed to support strategic mine planning decisions. The approach is equally applicable to the analysis of fully integrated system supply chains (pit-to-port), the evaluation of incremental capital investments to targeted areas of a supply chain, or when considering revisions to the operating philosophy of a system in the short term. The basis of each of the three analytic steps is explored in detail in this paper. The result is the definition of a structured mechanism for a business to actively manage risk and drive productivity as a component of the strategic mine planning process.CITATION:Fricke, C, Velletri, P and Wood, R, 2014. Enhancing risk management in strategic mine planning through uncertainty analysis, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 275–280 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 24, 2014

By B P. Wrench, M J. Gowan, P J. Chapman

Embankment dams constructed mainly of sand or non-plastic fine soils are susceptible to liquefaction, particularly in high-rainfall, high-seismicity environments where there is sufficient water to saturate the materials and sufficient energy from an earthquake to cause liquefaction. This paper shows the process adopted to review the stability of an existing cross-valley, centreline-raised cyclone tailings sand embankment dam.The study showed that two-dimensional stability analyses did not sufficiently capture the potential for instability, overestimating the depth of the critical failure surface. Instead, three-dimensional modelling was required to provide a reasonable representation. Post-liquefaction stability analyses carried out using the three-dimensional model indicated an adequate factor of safety (FoS). The FoS under seismic conditions was still considered to be a concern based on pseudostatic analyses (but noting the limitations of the analysis method).Earthquake-induced settlements were estimated using an empirical approach based on case history records (Swaisgood, 2003). The post-earthquake event settlement was estimated to be in the order of 600 mm, which is considered to be acceptable for the embankment, taking account of the proposed long-term freeboard of more than 8 m under operating conditions and 2 m under the probable maximum flood condition.CITATION:Chapman, P J, Wrench, B P and Gowan, M J, 2015. Review of static and seismic stability of a cross-valley sand tailings embankment in a high-rainfall, high-seismicity setting, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 163–172 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

The Australian Mining Industry Council (A.M.I.C.) was established in 1967 as a body to co-ordinate the interests of the mining industry on a nation-wide basis. Its member- ship now embraces the great majority of mining groups in Australia. One of A.M.I.C.'s major continuing functions since its formation has been to work with Governments towards the enactment of more effective and efficient mining legislation. Yet, over the period, the,overall position, if anything has deteriorated. The main reason for this was that because of the rapid succession of what appeared to be quite separate problems during the period there was never sufficient time for Govern- ments to take stock of a situation before it would be changed by a new set of circumstances. By early 1973, the Council was certain that most of the various questions raised were really part of the one overall land use problem and its work in this area thus took a new emphasis from that time. In discussing the Council's involvement with Australian mining legislation over the last six years, the paper helps to clarify the present situation. It then explains a land management system which the Council believes could pro- vide the basis for the type of enlighened

Jan 1, 1974

By Liu Q, Siefken T. C, Misra V. N

Investigation of the differential flotation characteristics between arsenopyrite and pyrite in a ore concentrate have been carried out on a laboratory Leeds flotation cell. Experimental results indicate that some limited separation between arsenopyrite and pyrite is possible by differential flotation under the conditions of high pH and low pulp redox potential. The best performance in this testwork was achieved by using an oxidizing agent at pH 10.7. Of the oxidizing agents tested, NaOCI gave better oxidizing effect than KMnO4. It has also been observed that the pulp redox potential depends on the pulp pH value. At high pH values a hydroxide layer is formed on the arsenopyrite surface, which has the effect of a depressant on the arsenopyrite.

Jan 1, 1992

By Ariti J

The mineralogy and extractive metallurgy of platinum and palladium in ores and residues is examined and the relative reactivity of Pt, Pd, PtS and PdS in cyanide and chloride media at 20¦C is discussed. Electrochemical measurements establish that Pd is readily leached in chloride media but more slowly in cyanide media due to a passivating PdO film. The passivating oxide film on Pt prevents leaching in either system at ambient temperatures. The results of leaching Au, Pd and Pt from an iron oxide residue obtained from the Sherritt Gordon Process using CN/air and Cl-/H202 are compared. It appears that passivation is overcome either by roasting at ?600¦ or by leaching at >_100¦C.

Jan 1, 1991

The coking coal produced by Utah Development Company in the Bowen Basin is processed by a dual system of dense media cyclones for the 30mm x 0.5mm feed and flotation for 0.5 x 0mm material. The basic metallurgy of these processes will be presented with emphasis on the operational characteristics which are peculiar to coal. Potential areas for process improvement by the application of more sophisticated control systems will also be discussed.

Jan 1, 1978

Opening AddressThank you for inviting me here today to open what promises to be a significant conference on the technological aspects of extractive metallurgy. I would especially like. to welcome delegates who have travelled great distances in order to contribute to, and be participants in, this examination of the technical innovations which have always been a crucial part of our industry.

Jan 1, 1992

By Y D. Jeon, K S. Kim, C-H Eom, C M. Yoon

The carbon neutrality continues to require reduction of carbon usage in ironmaking and steelmaking processes. Specially, it is expected that the hot metal ratio (HMR) in the steelmaking process should be reduced essentially. Unfortunately, the reduction of the HMR in converter can bring about poor environment for nitrogen removal from molten Fe. From this situation, nitrogen prediction model has been developed to understand the fundamental of behaviour of nitrogen and quantitatively interpret its content changes in the converter process. Thermodynamic and kinetic approaches were improved based on existing mathematical model and attempted to predict nitrogen content in realtime by combining process data. In present study, heat supply from the oxidation (mainly carbon and silicon) and CO evolution in the converter are considered, and scrap melting due to the heat transfer from the molten Fe to the solid scrap charged in the converter also be considered.

Aug 21, 2024

By S Li, Y Lei, X Wu, C Ma, W Q. Zhang

The failure of roof of thin bedrock working face under loose aquifer in a coalmine can lead to water-sand inrush disaster. Based on the accident of water-sand inrush in 30108 working face of a mine in Shaanxi province, China, the mechanism of water-sand inrush is theoretically analysed. The process and critical conditions of water-sand inrush in working face are reproduced by numerical simulation where the bedrock thickness is 20 m, the clay layer thickness is 40 m and the mining height is 6.5 m. The study found that under the condition of thin bedrock and thick clay layer, the characteristics of the clay layer have a significant inhibitory effect on the development of the fractured zone, and the development of the water-conducting fractured zone is incomplete and insufficient. However, in the process of continuous mining of multiple adjacent working faces, the strength of the clay is gradually reduced by the influence of mining and the erosion of water, and the height of the fractured zone is gradually increased. In the subsequent mining process of the working face, the roof is more likely to be cut-off and lead to water-sand inrush. From the initial failure of the clay to the final crack directly through the surface, the shear strength of the clay is reduced by about 52 per cent. Further simulation found that in addition to the characteristics of the clay layer itself, the main factors affecting the water-sand inrush in the working face caused by overburden failure also include the difference in bedrock thickness and strength, and the difference in coal seam mining height. With the increase of bedrock thickness, the development height of the fractured zone increases gradually with increases of bedrock thickness when the cutting failure of overburden rock no longer occurs. With the increase of mining height, the height of water flowing fractured zone also increases, but the cracking ratio gradually decreases. Therefore, it’s of great practical significance to systematically study the mechanism and critical conditions of water and sand inrush in mines and the main influencing factors for preventing similar accidents in mines with similar conditions.

Nov 29, 2022

Thank you chairman, good afternoon ladies and gentlemen. In my talk this afternoon I intend to cover a brief history, some of the recent experiences and an overview of the McArthur River project.If we consider the themes of this forum, Obstacles and Opportunities, I can confidently say that in attempting to develop the McArthur River deposit Mount Isa Mines Limited (MIM) must have encountered almost every obstacle that can be imagined. However the large size and the high grade of the deposit has ensured an opportunity, from which it is very difficult to walk away from.The McArthur River Here's Your Chance (HYC) Deposit is located in the Northern Territory of Australia. It was discovered by Mount Isa Mines Limited geologists in 1955 and is one of the largest known sedimentary stratiform zinc-lead-silver deposits. The deposit has been the subject of numerous investigations and considerable expenditure culminating in a major feasibility study in 1979. There were a number of factors which prevented development, these being the size of the project, the fine grained mineralization, geographical location, market, social and capital cost. The latter had been estimated in the 1979 study to be $800 million at that time.

Jan 1, 1993

The Callie Underground Gold Mine (Callie) is owned by Newmont Asia Pacific and located 531 km north-west of Alice Springs in the Northern Territory. Historically, stopes have been mined utilising a primary and secondary stoping sequence with cemented aggregate fill and rock fill respectively. Current and near-future mining will employ long hole open stoping with rib pillars and rock fill with a paste fill system approved to allow a higher extraction ratio from mid-2011. The Callie rock mass is of good quality with little or no mining difficulties during development and stoping to a depth of 1140 m below surface. Development is currently occurring at depth of 1360 m below surface. Stress damage previously observed only in secondary stope accesses is now observed in development unaffected by stoping stresses. A change in rock mass properties is being experienced with depth, with more pronounced and frequent joint planes. Also, other structures are intersected more commonly, such as lithological boundaries and fault zones. The 'Callie rock factory' mentality that has persisted for years is challenged. This paper covers an appraisal of the stress and ground condition changes at Callie. The appraisal outlines the mine design criterion that was developed and examines the transition from a low stress environment to one where stress damage is observed. Discussion includes a judgement on the rock mass damage observed in development, the dominant geotechnical factors influencing the change in ground conditions, and if a correlation can be made between the observed rock mass damage with stress through the use of numerical modelling.

Nov 25, 2010

By M Ma, W J. Bruckard, C Gontijo, R Holmes

Vale is the largest iron ore producer in the world. Since the 1970s, Vale has been using reverse cationic flotation to remove siliceous impurities from its iron ores. Whilst this flotation process has operated effectively for many years, it suffers from the problems of high reagent costs and high metal loss.In 2010, CSIRO investigated the use of a reverse anionic flotation process for Vale iron ore. Batch laboratory flotation studies conducted on Vale samples showed significantly reduced reagent costs and improved recovery of iron. In this work, the flotation behaviour of the different impurities in the Vale iron ore sample using reverse cationic and reverse anionic flotation processes is compared. Detailed flotation responses are presented and the merits of the two different flotation schemes are discussed.CITATION:Ma, M, Bruckard, W J, Holmes, R and Gontijo, C, 2013. Impurity removal in the reverse flotation of iron ore, in Proceedings Iron Ore 2013 , pp 427-430 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

As defined by both the Australian and New South Wales Governments the Illawarra consists of the Tablelands, the Local Government areas of WingecarribPe Shire, Bowral Municipality and Mittagong Shire, the Wollongong sub-region consisting of Wollongong City Council, Shellharbour Municipality and Kiama Municipality and finally the Shoalhaven Shire. I intend here to concentrate on community development in the Wollongong sub-region.

Jan 1, 1976

After considerable input from the mining industry, the Canadian Securities Administrators (CSA) finalised National Instrument 43-101: Standards of Disclosure for Mineral Projects. This Instrument, which became law across Canada on 1 February 2001, applies to all technical public disclosure on mineral projects and requires all technical disclosure to be based on the work of a æqualified personÆ (QP). While the QP is quite similar to the Competent Person in Australia there are important differences when it comes to all disclosure. This paper will summarise the main areas in which the Instrument introduces major changes to Canadian disclosure standards on mineral projects including the role and responsibility of the qualified person; the increased requirements to file technical reports; the incorporation by reference of the October 2000 CIM definitions of resources and reserves and additional rules governing written disclosure of scientific and technical information. In October 2001, eight months after the implementation of NI 43-101, the CSA compiled a list of frequently asked questions (FAQs) and CSA responses to assist mining industry participants and their advisors in understanding and applying NI-43-101. This document has been well received by industry. The CSA plans to update the FAQs when further guidance is requested. Two industry committees have been established to provide the CSA with technical advice on the application of NI 43-101. As recommended by the Ontario Securities Commission/Toronto Stock Exchange Mining Standards Task Force, the CSA has established an external industry advisory committee û the Mining Technical Advisory and Monitoring Committee (MTAMC) û to monitor the application of NI 43-101 and advise the CSA on industry and professional developments. The role of the CSA-Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Working Committee on Reserves and Resources is to ensure that the future changes and updates to the CIM Standards can be efficiently and effectively incorporated in NI 43-101. During this first year, the Canadian securities regulators have seen an improvement in the quality of disclosure on mineral projects, which will increase investor confidence in the industry.

Jan 1, 2002

As the mining industry looks to new technologies for a safe work environment and increased production rates, so should emergency response teams when dealing with organisational incidents. Implementation of technology has transformed the nature of incidents within the international mining community with lower frequency, high impact events replacing high frequency, low impact incidents of the past. In turn the approach to mines rescue response and preparation has naturally diversified. New rescue technologies when applied effectively can only further advance preparation and the response of mine rescues teams. This paper discusses some of the changes associated with mines rescue as the industry embraces technology. It highlights some recent rescue responses and their approach and gives examples of some of the new technologies being used for improved mines rescue.

Jan 1, 2004

By Denholm WT

The main objective of the experimental study was to investigate the dissolution kinetics of various forms of carbon under iron bath converting or smelting-reduction conditions, i.e., particulate, free moving carbon in contact with a turbulent iron melt. Iron/carbon melts were contained in cast magnesia-lined silicon carbide crucibles heated by a medium frequency induction furnace. The melts were stirred by injecting nitrogen through 2 mm I.D. alumina lances submerged to a depth of 50 mm in the 100 mm deep baths. Particulate carbon in the form of graphite, brown coal char and petroleum coke, were dropped directly onto the turbulent bath. The dissolution rates of the various carbon types were monitored by taking periodic bath samples for subsequent carbon analyses. The effect of carbon particle size (1-6.25 mm), the degree of bath turbulence (nitrogen stirring rates of 0-20 litres/min), and bath temperature (1300-1500¦C) were assessed. The analysis of the results was complicated by particle buoyancy effects, but it was established that the dissolution rates of the three carbon types investigated were similar, and increased linearly with increases in the gas stirring power inputs. Particle size had relatively little effect on the dissolution rates.

Jan 1, 1984