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This paper describes the development of an approach to sustainable development for application at the feasibility study stage for a proposed bauxite mine near the community of Aurukun, south of Weipa on the western coast of Cape York Peninsula, Queensland, Australia. The general environment for development was complex in all dimensions. In particular, the socio-demographic profile of the Aurukun community (population 1200) characterised it as being amongst the most disadvantaged communities in Australia. The traditional owners of the area, the Wik and Wik-Way people, were at the forefront in the efforts of Indigenous people in Australia to secure land rights over the past 30 years, and they had previous experience negotiating an Indigenous Land Use Agreement (the Western Cape Communities Coexistence Agreement) with Rio Tinto Alcan, the operators of the Weipa bauxite mine. Through this they had shown a well-founded sense of entitlement with respect to the development of resources on their traditional land. The Queensland State Government had recently cancelled an existing mining lease over the bauxite resource as the holder of the tenement had not fulfilled the terms of a development agreement that had been in place for 30 years. The Government was anxious to avoid any future æbankingÆ of the resource, and had decided to offer tenure to the resource on an international competitive basis, subject to the requirements of the Commonwealth Native Title Act 1993. This would require a negotiation process with traditional owners and potentially involve companies with whom the traditional owners had no existing relationship (typically developed during the projectÆs exploration phase) and who possibly had no project development experience in Australia. As well, the State Government envisaged an approach to development that drew on the significant work that industry and other stakeholders had undertaken over the previous ten to 15 years, commencing with the mining, minerals and sustainable development (MMSD) process. This work was aimed at rectifying acknowledged deficiencies with industry recognition of stakeholder interests, in particular with respect to environmental management and socioeconomic development. The approach adopted aimed to define the strategic community interests and sustainable development outcomes to which the development of the resource would be expected to contribute, and to embody these within an easily usable management structure that could be applied to each stage of project development from feasibility study through to mine closure. The logical framework (AusAID, 2006; ICMM, 2005) was the management tool utilised to order the identified interests and desired outcomes. The structure included components aligned with the key areas of development interest expressed by the community, and the initial baseline sustainable development plan (SDP) developed established component objectives, outcomes, indicative outputs and activities for the feasibility stage of the project. This established an objective framework to guide potential bidders when developing their response to the State GovernmentÆs Request for Proposal. The paper will describe the evolution of the competitive process and the parallel process for development of the SDP. While the institutional environment was politically and socially complex, the use of simple visual representations of the environment and the analysis and ordering of issues, objectives and criteria through methods such as stakeholder analysis and the logical framework approach, enable the development of a dialogue on the contribution that the development of a mining project can make to sustainable community development, and for the development of an agreed program of community support to capture the contribution. The use of the logical framework was found to have good functionality for plan development. Achieving plan outcomes though, is highly dependent on the skill of key project personnel in facilitation, team building, conflict resolution and leadership, as well as their ability to influence the behaviour of key stakeholders with the capacity and authority to require the integration of local economic development criteria in to key project development decisions.

Jan 1, 2009

Rio Tinto Iron Ore is currently working towards finalising comprehensive Native Title land access agreements, which cover all of the current eleven mines and infrastructure owned and operated by the company in Western Australia's Pilbara region. Critically, the agreements represent a mutual commitment to a long-term relationship and address many areas of concern by promoting indigenous enterprise, well-being and regional development opportunities. Our objectives in the process are to obtain the informed consent of the traditional owners for our Pilbara expansions while providing benefits to them in a way which provides lasting and substantial improvements to health, education, housing and real jobs in the mainstream economy.   To facilitate the agreement negotiations, Rio Tinto Iron Ore (RTIO) proceeded in 2005 to research and design a specific strategy around Aboriginal relations and local community engagement in the Pilbara. Wherever we operate, Rio Tinto follows a fairly simple formula in working with communities, which is comprehensively aligned to local context.   This presentation provides an overview of Rio Tinto Iron Ore's community engagement strategy in Western Australia's Pilbara region. It will also explore the establishment of regional standards on employment, business development and contracting that have been developed to ensure Indigenous people are engaged in the development of their region and are able to contribute to supporting the growth and development of mining in the area with the expectation that there is prosperity for all. This is an ABSTRACT ONLY no paper was prepared for this presentation.

Jun 1, 2010

THE following paragraphs represent an endeavour to describe, briefly the equipment used for the manufacture of sulphuric acid and superphosphates by the Corporation.SULPHURIC ACID PLANTS.Two separate units are in operation, No. I Plant working on sulphur dioxide generated from pyritic ore, No. 2 Plant working on sulphurous gases obtained from the Huntingdon-Heberlein desulphurizing process. The latter plant is unique in being the first installation for the successful use of these gases.

Jan 1, 1918

By V M. Silva, P A. A Martins, V O. Matthew, A L. S Fonseca, E B. Cunha, A J. D Ferrari, E M. S Silva, A C. Silva, D R. T Vilela

The Anglo American phosphate mine is located in the Brazilian state of Goiás and possesses one of Brazil’s most important phosphate rock deposits, with the site being the country’s second largest producer of phosphate rock concentrate. Despite the site having been in operation since 1979, the mining team only started using explosives in 2004 when rocks with greater hardness started to appear in the mine’s geological profile. Rock excavation was previously performed mechanically. Until 2013, only rocks with high hardness were blasted, this following the standard drilling grid that was defined in 2004 without any changes in the blast parameters. The aim of this paper is to show how fragmentation optimisation has yielded positive results at all stages of the production chain, from the mine to the mill passing through an impact hammer crusher, a rod mill and ball mill, operating in close circuit with hydrocyclones.While incorporating the mine to mill holistic approach during the operational integration, the focus was on defining the blasting domains and respective optimal fragmentation and measuring the benefits of blasting in terms of reduction in energy and grinding media consumed in the comminution processes. In the first stage, the blasting team made changes to the blasting parameters and assessed the effects of these changes on fragmentation using computer software and on-site measurements. This generated a database that made it possible to divide the mine into blasting domains. For the second stage, teams from the plant, geology, mine planning and operation departments jointly made comparisons between the performance when processing stockpiles, which only included high hardness blasted ore (20–30 per cent of blasted ore). Changing the drilling grid’s size from 3.0 m × 3.8 m to 2.0 m × 2.6 m for high hardness rock with the presence of silicates resulted in a 40 per cent reduction in the P80 for the blasted material (from 459 to 278 mm), while changing the grid from 3.0 m × 3.8 m to 2.6 m × 3.2 m for high hardness rock without the presence of silicates generated a reduction of 25 per cent (from 270 to 204 mm). There were gains observed from the measurements at the mineral processing plant in terms of specific energy spent on comminution and on the consumption of grinding bodies in the rod mill. There was a measured reduction of circulating load during secondary grinding and a reduction in slime generation.CITATION:Silva, A C, Martins, P A A, Silva, E M S, Fonseca, A L S, Ferrari, A J D, Cunha, E B, Silva, V M, Matthew, V O and Vilela, D R T, 2015. Fragmentation optimisation – adopting mine to mill for reducing costs and increasing productivity, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 363–368 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By S Novak

A world-class example of sustainable development in practice, the Local Resource Development Initiative (LRDI) grew from agreements between the Ambatovy nickel mine developers and the Government of Madagascar. A program of training and community development, the LRDI aims to maximise local benefits by optimising the integration of local resources during the construction period of the mine. By local resources, we mean the local labour force as well as local goods and services. Begun in 2007, the foundation of the LRDI is to integrate local resources into the mining project and where gaps are identified, design and implement training, mentoring and other programs to fill those gaps. The principal accomplishments are: the establishment of training centres that trained over 4000 people in little over one year, 96 per cent of whom hired to work at the mine; a support program for local micro, small and medium enterprises that has led to the award of 65 contracts for goods and services with training and mentoring of over 100 local businesses; and a number of special projects that have, among other results, strengthened local agricultural development and created employment for young people. The LRDI provides unique insights into key indicators and lessons learned to strengthen the social and economic sustainability of mining projects in developing countries. The paper will discuss these in terms, among others, of: the importance to project success of upstream planning to address socio-economic issues; the role of civil society and other local partners to strengthen and expand sustainability outcomes, and to spur governments to demand that major projects promote economic and social sustainability; and the integration of mine sustainability with sustained regional social and economic development.

Jan 1, 2009

By D Kepert, C Simpson, D Edwards

Channel iron deposits (CID) currently supply over 40 per cent of the seaborne iron ore trade out of the Hamersley Province. The two well documented producing systems (Robe and Marillana palaeochannels) were both discovered during early reconnaissance mapping principally by BHP Billiton (BHPB) and Geological Survey of Western Australia (GSWA) during the mid 1950s to early 1960s. Both crop out extensively over the majority of their length. Hot on the heels of Fortescue Metals Group 2004 - 2005 discovery of approximately 2.6 billion tonnes (Bt) of undercover iron ore mineralisation in the Chichester Range, the Fortescue Exploration Department turned its attention elsewhere throughout the Hamersley Province. Reappraisal and analysis of publicly available data and ground truthing of developing models led to the recognition of the Solomon palaeochannel system. Subsequent exploration defined a world-class Resource of some 1.9 Bt of iron ore mineralisation of which the great majority is buried CID. Apart from the Marillana CID system, the Solomon region is the only major CID with significant tonnes of sub two per cent alumina CID with over 500 Mt delineated to date. Exploration has also outlined significant supergene bedded and detrital iron ore mineralisation. Ongoing drilling is expected to increase the resource base both in terms of tonnes and confidence. This paper outlines the principal contributing factors which led to the discovery of the Solomon CID and compares its geology with the Robe and Marillana palaeochannel systems.

Jan 1, 2009

Slide presentation at conference

Jan 1, 1996

By Norman TE

The design of composite materials for wear resistant service aims at com- bining two or more materials in such a way as to achieve unique and useful properties not generally available in any single homogeneous material. Properties and applications are presented of what might be described as a new generation of wear resistant materials, namely, metallic and part- metallic composites suitable for use in the high abrasion/moderate impact environment encountered in the crushing and screening of ore. Significant cost performance benefit can result from the use of such materials and several specific case histories are discussed. Some promising new developments, utilis- inn white iron and rubber, as yet in the field testing stage, are reviewed. Further comments are offered foreshadow- ing new composite developments, as yet untried but which appear to h,uve merit.

Jan 1, 1978

By D J. Kilkenny, D A. O’Toole, P B. Hills, K L. Seah

An investigation was undertaken to critically analyse the use of fibre reinforced shotcrete (FRS) for a variety of applications in large diameter shafts. Those applications included the use of FRS with or without the addition of subsequent rock bolting in the temporary support cycle prior to the installation of a permanent lining, most likely cast in situ concrete or as the final lining medium.Numerous authors have considered the early re-entry and strength characteristics of FRS in recent years. The current study has investigated the practical application of the recommendations of many leading authors in an endeavour to establish practical and acceptable risk-assessed procedures for the use of FRS for rapid, safe, efficient and cost-effective shaft sinking.Shaft sinking is regarded as a specialist and potentially higher risk activity due to the confined work environment, exposure to ground conditions and a high degree of manual handling associated with getting materials to the sinking face. The use of robotically applied FRS as a primary lining in shaft sinking has significant safety advantages in reducing manual handing associated with mesh safety support and bolting, as well as reducing direct exposure to ground conditions.The study involved both field testing and a literature review. The study established an initial set of criteria for the use of FRS in the development of large diameter shafts and demonstrated a number of scenarios where the technique of robotically applied FRS provided significant safety and cycle time advantages. The opportunity for a fully sprayed single pass lining was also investigated as part of the project.CITATION:Hills, P B, O’Toole, D A, Kilkenny, D J and Seah, K L, 2014. Exploring the use of fibre reinforced shotcrete in large diameter shafts, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 295–306 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By S Long, D Carnovale, L Louwrens

The Mt Wright underground mine (MTW) is located near the town of Ravenswood in north Queensland and is operated by Carpentaria Gold – a wholly owned subsidiary of Resolute Mining Limited.The Mt Wright mine has gone through many stages, from the conception and implementation of the world first ‘sub-level shrinkage’ stoping (SLS) with continuous fill mining method in 2010, through to steady state production. These have been outlined in detail in papers presented by Mackay (2011) and Mackay, Long and Koen (2014) at previous Underground Operators Conferences.Since the last paper was presented, MTW has experienced significant change in two key areas.The first significant change was the discovery of a previously unknown hazard in the form of flat rilling events (FREs) from closed drawpoints (DPs). These events are believed to be unique to MTW and pose a significant risk to both the safety of personnel and the business as a whole. The paper will discuss this hazard and the evolution of the controls and practices that have been introduced to mitigate the risk posed by the identified hazards. The material involved in these events is extremely dry, fine and hot.The second significant change is an altered stress regime bought on in part by a change in the production front orientation and a general deterioration in ground conditions in some areas of the mine. This has caused some production interruptions at MTW. The second half of the paper will describe the challenges encountered, the mechanisms behind these challenges and the strategies implemented to safely return MTW production to planned levels.It is believed that other operations can learn from the issues mentioned above, and the paper has been written with this in mind.`CITATION:Long, S, Carnovale, D and Louwrens, L, 2017. Mt Wright – managing unique risks, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 295–304 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

Digitally enhanced Landsat MSS images are being used'in delineating the structural and tectonic features in the Arabian Shield as part of a project funded by King Abdulaziz City for Science and Technology (KACST) of Saudi Arabia. The delineated features together with statistical modeling and structural analysis are to assist in an improved understanding of the evolution and mineralization of the Arabian Shield. Specific emphasis is to be given to relating the extracted linear features to the location of known mineral occurrences and areas of potential geologic hazards. A number of textural (spatial) and spectral enhancement techniques have been applied, to the MSS data covering selected areas, in selecting the most optimal enhancement product for visually delineating the structural geologic .features.

Jan 1, 1988

By Greenwood-Smith R, Ellis W. K

A bulk analyser based on the gamma-ray resonance scattering process can be used to give a rapid and accurate measure of the percentage by weight of copper or nickel averaged over a large mass of sample, typi- cally 20 kg. It is shown that for a bulk sample containing about 3 wt.% Cu, crushing to -25 mm is the only sample preparation requited for analysis to within an error of about 0.06 wt.% Cu (errors quoted are one standard deviation). A comparison of bulk analyser and con- ventional assays on the same bulk samples can be used to estimate the sample preparation errors in the conventional methods. The squared deviations between bulk analyser and conventional assays are approximated by the sum of variances in sample preparation, conventional analysis, and bulk sample analy- sis. The sample preparation error was esti- mated as 0.26 wt.% Cu for samples crushed to -2 mm before splitting, 0.08 wt.% Cu for samples crushed to -0.35 mm before splitting, and 0.04 wt.% Cu for the average of 15 grab samples from bulk samples which had been crushed to -2 mm. The average copper grade for each group of samples was about 1.7 wt.%. Results are presented which show that

Jan 1, 1976

ADDRESS BY THE PRESIDENT OF THE INSTITUTE (MR. J. G. SYMONS) IN PRESENTING THE AWARD TO ELLIOTT SYLVESTER TIMOTHY O'DRISCOLLTim O'Driscoll comes from a mixture of Irish and Scottish stock. His family on the paternal side settled on land in Western Australia in the middle of the last century. His family on the maternal side were part of the W.A. goldfields scenc, including places such as Kanowna, and the Great Fingal mine, near Cue, where his grandfather lies buried.The combination of land and mining environments may perhaps have contributed to an innate interest in geology shared by Tim and his two brothers, all of whom became geologists.Tim showed an early liking for mathematical and geometric subjects, and in his B.Sc. studies at the University of Western Australia he took a major in mathematics along with geology in 1940.His first job was on the Kalgoorlie Golden Mile, and then at Norseman. After serving as a flying boat navigator in the north and south Pacific theatres in World War II he returned to Kalgoorlie and thence to Broken Hill.

Jan 1, 1977

By A Calderon, J Harris, M Shi, D Viswanathan, C Ribeiro Duthie, P A. Kirsch

Mineral resource development activities impact the health and well-being of many people, from workers, to families and surrounding communities. In the current environment of corporate social responsibility life-of-mine planning considers that mining activities should be conducted in the best environmentally, socially and economically acceptable way for the entire life of the mine (ie from exploration to decommissioning and closure). In this context, the health impacts of mining extend throughout the life of the community from worker injury and chronic exposure to communicable and non-communicable causes of illness, through to family and community health and well-being. At the inaugural Life-of-Mine conference in July 2012, the authors proposed the life-of-mine in the life-of-community (LOMLOC) matrix as a framework for understanding issues at the interface between resource extraction operations and the surrounding environment.This paper reviews and compares health activities extracted from social and environmental reports published by selected major mining companies with American operations in Canada, Colombia and Brazil. These corporate approaches to public health management are mapped to the LOMLOC matrix to identify and compare trends and behaviour in corporate health investments. This analysis of how companies approach and prioritise health issues in the context of different regions, cultures and environmental drivers will serve as a resource for minerals industry managers, civil society and regulators regarding current health management approaches in this sector.CITATION:Ribeiro Duthie, C, Calderon, A, Viswanathan, D, ?Shi, M, Harris, J and Kirsch, P A, ?2014. Resource company investments in health – a life-of-mine / life-of-community perspective across America, in Proceedings Life-of-Mine 2014 , pp 349–364 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

Consolidated Rutile Limited (CRL) was one of the best performing mining stocks of the turbulent 1980s, having a very high payout of franked dividends. In contrast to some other mining groups, it was not highly involved in the speculative lead-up to the 1987 sharemarket crash. Its base was firmly laid through a succession of decisions that were taken in the period 1982-1985. These decisions and the rationale behind them are outlined in this paper. CRL began the 1980s in a highly favourable position. It had successfully pioneered the transition to high-throughput mining of the high dunes on North Stradbroke Island (NSI), commissioning its 2100 tph cutter suction dredge at the Bayside reserves in 1978 at the time of rising prices, such that it was able to pay off its modest bank loan within 18 months. The June 1980 results showed a record after-tax profit of $5.6M, from total assets fo $26.5M and sales tonnages of rutile and zircon of around 50,000 tonnes each.

Jan 1, 1991

By J Meikle

A projected image is not always a true representation of a situation, or indeed an industry. This is often the case of the mining and minerals industry, which has frequently been portrayed in a negative light with a male dominance stigma attached. However, these issues can be combated for both the industry and its future, current undergraduate students, through undergraduate industry experience. In particular, vacation work enables female students to dispel many myths surrounding the industry and realise that the mining and minerals field offers career development for both genders. This paper will discuss how vacation work enables students to make important career decisions even before they have graduated. Industry experience provides undergraduates with the opportunity to gain practical knowledge relevant to their field of study. Additionally it allows students to observe the nature of the industry and the sacrifices necessary to advance careers. The prior insights into an industry are relevant to all students, but particularly female students, who might otherwise be dissuaded from a career in mining. This paper is written from the perspective of two female undergraduate students studying Mining and Minerals Processing Engineering.

Jan 1, 2006

The relationships between Aboriginal Traditional Owners and mining companies have often been mired in dispute, particularly since the High Court Mabo decision and the Native Title Act of 1993. In the Pilbara region, Rio Tinto Iron Ore (RTIO) impacts the traditional country of 12 Aboriginal Traditional Owner/language groups. Over the past 12 years the company and the Traditional Owners have negotiated and settled several significant land use agreements including the Yandi Land Use Agreement over the Yandicoogina mine in 1997, between Hamersley Iron (now Rio Tinto Iron Ore) and three language groups û the Bunjima, Nyapaili and Innawonga people and the Eastern Guruma Indigenous Land Use Agreement (ILUA) of 2006. These substantive agreements are now being followed by a new generation of region wide ILUAs which are close to conclusion. Arising from these regional agreements is a new framework for engagement which has been informed by the implementation of the previous agreements in the Pilbara and across the Rio Tinto group of companies. They are driven by both a company desire to have a consistent approach to engaging with Traditional Owners and the Traditional Owners wanting to have a similarly transparent and consistent standard of performance by the company in implementing the agreements which can deliver improved employment, cultural heritage engagement and direct and indirect benefits for the life of mining by the company. During the past three years the growth in the Pilbara, Western Australia brought new opportunities with people flocking to the region for employment flowing from the mining boom. Housing was at a premium and FIFO (fly-in, fly-out employment arrangements) was developed as a method to manage the general growth and demand for skills. Despite the recent down turn in the world economy since September 2008, which has reduced demand for minerals, the Pilbara continues to enjoy high levels of employment and as a result there is still significant pressure on housing and services provision. Although there has been vast economic growth in the Pilbara not only by mining companies but also oil and gas companies, the 2006 census data indicated that the direct benefits of improved employment, business development and engagement in the mainstream economy continued to exclude Aboriginal people. Indigenous people constitute a significant proportion of the population in the Pilbara region, some 6000 people û currently 14 per cent of the population rising to 18 per cent by 2015 û yet they remain at the bottom of the socioeconomic scale. More than 40 years of mining has returned relatively little to this group of people who are the permanent residents of the region and are connected through their traditional culture to this country (Taylor and Scambary, 2005). Ensuring local Aboriginal participation in the mainstream economy has been a challenge for resource companies, Traditional Owners and local residents in the Pilbara. The case study explores the relationship between a mining company û Rio Tinto Iron Ore and the Traditional Owners of the Pilbara. It examines two projects that have been developed to engage Indigenous people in the development of their region and through regional representation and business development to build a sustainable future for themselves and their future generations and at the same time ensure social cohesion to support social licence to operate. The case study also examines the process that was followed by Rio Tinto Iron Ore and its operations in undertaking a regional agreement for land access, participation and the integration of local Indigenous people into their business and the local economy.

Jan 1, 2009

By A G. Grice

WMC Resources Pty Ltd û Copper Uranium Division operates the large underground Olympic Dam Mine at Roxby Downs, South Australia. These operations mine and process the ore to produce refined copper, uranium oxide, gold and silver. In mid-1996, the company committed to the Olympic Dam Expansion Project (OEP) to expand production from 3.0 million tonnes per annum of ore (85 000 tonnes per annum of copper metal) to over 9.0 million tonnes per annum of ore (over 200 000 tonnes per annum of copper metal). Along with the increase in the ore production capacity of the underground mine and the surface ore handling and processing facilities, expansion of the backfill system was required. The target backfill placement rate was 2.0 million cubic metres of backfill per annum which was to be predominantly delivered as cemented aggregate fill (CAF). This paper discusses the engineering activities undertaken to assess and change the method of designing the required strength of fill exposures. In addition, the operational changes that were introduced to achieve the required fill quantities and the mix designs to meet the specified strengths, including the use of alternate binders, are discussed. This work resulted in a large increase in the fill placement rate and a reduction in the overall unit cost of fill.

Jan 1, 2000

By J B. Pateiro-Fernßndez, M Fuchsschwanz, G Deissmann, S Ahmad

Quang Ninh province is the most significant coal producing region in the north of Vietnam. The Nui Beo Coal Company (NBCC) operates open pit mines in Quang Ninh province and the waste overburden produced is dumped as sidehill fill in the Chinh Bac waste dump site. In the past, no special consideration has been given to the environmental impacts during the dumping operations. The mine waste is transported in trucks from the mine site to the dumping site and the loading, hauling and dumping operations are the main sources of dust emission. Rain events, especially during the rainy season, cause the generation of contaminated surface water as well as seepage of water through the dump at a number of locations. The existence of cracks at the top of the dump can pose serious stability problems with heavy rain events leading to failure of slopes which can potentially disturb vast areas of land currently used for agricultural purposes and human settlement. For sustainable development at the Chinh Bac waste dump site in the future, apart from the social and economic considerations to be assessed, there is an absolute necessity for environmental protection measures to be in place both during and after the dumping of the mine waste overburden. Research Association Mining and Environment in Vietnam (RAME) is working to develop and implement concepts for the mitigation of environmental problems emerging from dust, contaminated water and lacking slope stability to ensure successful rehabilitation of the coal mine waste dumps in the north of Vietnam. Within the framework of RAME, the Institute of Mining Engineering I (RWTH Aachen University) is managing and working to develop the stabilisation concepts for the solid mine waste dump in collaboration with the Chair of Geotechnical Engineering (RWTH Aachen University), Brenk Systemplanung and the Vietnamese group of companies VINACOMIN (Vietnam National Coal-Mineral Industries Group). The most economical and environmentally sound operations, as well as locally adaptable environmental protection measures, are essential for the sustainable development of the dumping operations at Chinh Bac dump. This paper describes the dump site and the sustainable development possibilities with an emphasis on the environmental protection and stability problems at the Chinh Bac waste dump.

Jan 1, 2009

Gravity gold recovery has been practiced for thousands of years, making it one of the oldest forms of mineral processing. Gold is 19 times heavier than water although the barren rock is generally only 2.7 times heavier. Any potential gold ore needs to be characterised to assess its amenability to a gravity recoverable gold (GRG) process based on well planned and executed test work. Scale up considerations need to be considered in designing a gravity circuit. The economic impact of a gravity circuit should be justified based on the installed cost and likely benefits. Maximising gravity gold recovery results in a faster cash flow, lower operating cost per ounce and higher overall gold recoveries compared to the several weeks required to recover gold adsorbed onto carbon. The advent of centrifugal concentrators such as the Knelson and Falcon, coupled with intensive leaching of concentrates (ILR), has revolutionised gravity gold circuit designs. Considerations associated with the sizing of the centrifugal machines and the percentage of the circulating load (bleed) that should be processed is discussed in this paper. The trends with gravity circuit layout, engineering, as well as optimum dumping cycles, are important areas which require close consideration. Key aspects of these are presented in this paper. There are a number of circuit configurations to be considered, including the integration of different gravity concentrators. Other gravity process design considerations such as fewer modules, the effect of equipment size and enhancement of process efficiency using preconcentration, together with factors that affect OPEX and CAPEX are addressed. Practical considerations of maintenance, security from theft, minimisation of risk and water balance considerations are discussed using different equipment and circuit configurations. The trend towards using gravity recovery in flotation plants is also reviewed. A number of examples are cited and good design aspects highlighted.

Aug 1, 2010