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By M Dalm

More and more mining companies are becoming aware of the potential benefits of sensor-based ore sorting and process optimisation. This is reflected by a growing number of analysers that are available for drill hole logging, conveyor belt scanning, ore sorting, slurry analysis, etc. These tools all rely on a specific sensor technology that can be used to detect a material property such as colour, density, mineralogy, or chemical elements. However, all sensors have restrictions on the minerals and/or elements that can be detected or inferred. This is caused by the physical mechanisms behind the technology and depends on mineral concentration and compositional heterogeneity of the ore. Since nearly every ore deposit is unique in composition and characterised by different geological features that drive heterogeneity, no one-size-fits-all sensor solution is available. This makes it difficult for mining professionals to find suitable sensing technologies that can help them solve problems and improve processes for their specific ore types.

Sep 1, 2024

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

By Guo-Zheng J

This paper describes the risk management strategies adopted to control unstable slopes in the east open pit of the Daye iron ore mine. Extensive experience has been developed over the last 35 years in the management of pit wall instability resulting in the successful excavation and reinforcement of pit slopes over 350 m in height.

Jan 1, 1994

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

By S Marshall, A Fowler

The Augusta underground mine at Costerfield in Central Victoria has been in operation since mid 2006; however, AGD Operations Pty Ltd have explored and undertaken open pit operations in the area for over 20 years. The high-grade, narrow gold-antimony orebody is being mined using both mechanised and hand-held methods, to produce up to 70 000 tonnes per annum at ten grams per tonne gold and six per cent stibnite. AGD Operations Pty Ltd processes the ore on site using gravity and flotation to produce two products; a concentrate which is sold to Chinese smelters and a gravity concentrate which is refined off-site. The circuit achieves up to 30 per cent recovery of gold from gravity methods. There are many challenges in the underground mine, including an orebody with an average width of 300 mm, very poor rock mass conditions in the host rock and variable dips in the ore along strike, between 45¦ and 90¦. The upper levels of the mine have been developed ready for stoping; however, their depths range from 20 m to 70 m below surface in both oxide and transitional material. A major fault structure consisting of mud has been encountered underground and is associated with the orebody causing very poor ground conditions, water inflow and requiring additional reinforcement. The northern limit of the mine is defined by the proximity of historical workings in the South Costerfield mine, which is being continuously dewatered.

Jan 1, 2008

Currently all engineering schools face a common problem, an ever expanding technological base which must be presented to students within a fixed time period. Traditionally the programmes of study taken by engineering students destined for employment within the mineral industry include formal instruction in aspects of management to an extent greater than that presented in other engineering disciplines. Providing an adequate coverage of an expanding technological base within a fixed time span can lead to a reduction in the time available for 'non-technical' subjects, such as 'management'. This situation calls for periodic review of course contents and allocations of time. Following consultation with an Advisory Committee representing the mineral industry, mining research establishments, and kindred teaching institutions, the University of Melbourne has revised its mining programme. This programme is offered as an example of how aspects of management such as communications, economics, labor

Jan 1, 1980

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 Favreau RF

Over the last 20 years the blasting industry has progressed from the stage of being artform to a science as it is today. The use of computers to simulate blasting results has allowed blasting engineers to accurately pre- dict blast results and to optimise their blasting. This paper describes the computer blast simulator called BLASPA and its various applications in blasting. BLASPA allows the blasting engineer to predict blast results given known details of explosive properties, their distribution, rock type and properties, hole size, burden, spacing, collar and subdrill. The simulator runs mathematical situations and outputs numerical estimates of fragmentation and muckpile results. The paper discusses results which show that the mathematical outputs correlate very closely with actual results seen in the field, thus confirming the validity of the simulator. BLASPA can be used to help improve blast design by predicting stress levels in the rock mass and consequent rock breakage.

Jan 1, 1986

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 Ho SE, Neil Phillips G, Houstoun SM

There are numerous individual gold deposits in the Archaean greenstone belts of Western Australia, but only 26 have productions and/or quoted reserves in excess of 10 tonnes Au. Most gold production has come from mineralization in shear zones, quartz veins or stockworks in volcanic or intrusive host rocks, particularly tholeiitic basalts or dolerites metamorphosed at sub-amphibolite facies (e.g. Kalgoorlie). Significant prod- uction has also come from BIF-hosted deposits (e.g. Hill 50), and large reserves are quoted for mafic hosts at high metamorphic grade (e.g. Big Bell). Most deposits have marked structural control, great depth extension, and are characterized by zoned alteration haloes of pyritization (with Au), K-metasomatism and carbonation. On the regional scale, most larger volcanic- or intrusive-hosted deposits occur in younger (ca 2.8 b.y.) rift-phase green- stones (Norseman-Wiluna Belt). These belts also have a high prospectivity (36 kg Au/km2 of greenstone belt). Younger (ca 3.0 b.y.) and older (ca 3.5 b.y.) platform-phase green stones of the Murchison and Sodthern Cross Provinces and the east Pilbara, respectively, are progressively less prospective (14 kg Au/km2 and 0.8 kg Au/km2, respectively) and also have progressively smaller deposits. The important regional- and local-scale characteristics of most gold deposits can be explained in terms of a metamorphic- replacement model. In this model, metamorphic H2O-CO2 fluids, focussed by faults and shear zones, infiltrated host rocks and deposit gold at 350 + 50¦C and 1-2 kb, largely in response to fluid-wallrock interaction. In many large deposits, gold precipitation was synchronous with sulphidation of Fe-rich host rocks, but the diversity and abundance of smaller deposits reflects the variety of reactions precipitating gold from ubiquitous, auriferous metamorphic fluids. Regional variations in abundance and size of deposits relate to factors such as tectonic setting, alteration styles and possibly source rocks.

Jan 1, 1986

By Prakash AJ, Singh PK, Dhar BB

Safety and stability of underground mine openings, coal pillars and water dams in the near vicinity of operating surface mines are endangered from excessive blast induced vibrations. This paper deals with the investigations carried out in four coal mines. Simultaneous measurements at equal distances from the source indicated higher level of vibration on the surface than those produced in the underground workings. The values of peak particle velocity (PPV) measured on coal pillars, body of water dam were lower than those measured on roof and junctions of the roadways. The parting of coal (3-4.5 m) between two sections vibrated with higher PPV compared to the roof of top section and floor of bottom section. In one case the influence of total charge fired in a round was significant in generation of vibration compared to the maximum charge/delay where monitoring was done vertically below the source.

Jan 1, 1995

Three separate and unconfined aquifers occur in the Hilton area, named relative to position in relation to ore horizons: Footwall Aquifer in the east; Ore-Zone Aquifer within the ore-bearing Urquhart Shales; and the Hangingwall Aquifer in the west.It is the on-going strategy it Hilton to drain the Ore-Zone Aquifer which occupies structurally- and sulphide-controlled leached zones in the steeply west dipping strata. The aquifer affects considerable ore reserves to 480 m below the surface. Dewatering began in 1976, and is essentially completed to 4 level (240 m below surface). Dewatering efforts are now based on 8 level (480 m below surface).

Jan 1, 1993

By Oda Y, Hashiuchi M

In the smelting section, flexible fuels such as coal or coke are used in place of heavy fuel oil in order to utilize energy sources more efficiently. Heat recovered from the off gas of the furnace has been converted by the waste heat boiler into steam, which is used for self power generation and for heating or maintaining various temperatures. The amount of the recovered steam in the smelter is currently increasing due to maximum utilization of powdered cokes. The heat source required to maintain the temperature of the electrolyte in the tank house is electric power and steam. However until recent year this steam was provided by its own heavy oil combustion type boiler in the tank house since the amount of steam consumed in heating the electrolyte is large. Though experimental work over the last few years has shown the advantages of reducing steam in the tank house by fully covering the cell, the implementation of the full cover can lead to other operating problems. However various improvements, mainly the covering of the cell with a simple device, have led to greatly reduced steam consumption. As a result, steam for the tank house is now provided by the waste heat boiler only bringing more efficient energy usage.

Jan 1, 1987

The Black Star lead and zinc ore-bodies, situated in the western zone of mineralisation at Mount Isa occupy an area 2000 ft. long with varying widths from 100 ft. to 300 ft. The strike is N5°W, and the average dip 60° West.To test at depth the potentialities of this area, an extensive diamond drilling campaign was commenced on 16th October 1927. It was continued, with from one to six machines working, until the end of 1931. During this period, 26 inclined holes, with an average depth of 1224 ft, and a total footage of 31,828 ft. were completed. A vertical hole, 2452 ft. deep, for comparative purposes, has been omitted.These drilling operations came directly under the charge of G J Gray, General Superintendent of Mount Isa Mines, and, in the early stages were supervised by E. D. McDermott, of the Mining Trust, London. The foremen, who were in charge of various sections of the drilling operations, were: H Vale, F Bray, J Winston and A A Sanstedt.

Jan 1, 1932

By L Clarkson, D Williams, P Redcliffe, F van der Wal

This research presents a snapshot and insight into the trends, patterns, and common considerations identified in the current standing of real-time tailings dam monitoring practice. Based primarily on information derived from concurrent research by the author (in form of a Catalogue of Real-time Instrumentation and Monitoring Techniques for Tailings Dams), challenges and opportunities when transitioning to a real-time monitoring system are discussed. Learnings and key considerations between different monitoring approaches are explored, including themes of limitations and advantages that were observed consistently through global supplier feedback.

Jul 1, 2021

By P York

The study commenced in October 2012, to understand the basic ecology of the spotted-tailed quoll (Dasyurus maculatus) and to confirm whether the species utilise previously mined land on the Mt Owen mine site that was rehabilitated in 1996 to 2011, as part of their home range. The spotted-tailed quoll is a widely distributed marsupial carnivore that is listed as rare or threatened in every state in which it occurs. The species is a forest-dependent marsupial carnivore that occupies a wide range of habitat types (Long and Nelson, 2004).The first part of the study involved trapping a spotted-tailed quoll and fitting the individual with a combined global positioning system / ultra high frequency (GPS/UHF) radio-transmitter collar (Telemetry Solution – Quantum 4000E). The benefit of the GPS/UHF collar is that it records locations (or fixes) at intervals programmed by the user. The UHF component allows the researcher to locate the individual at a frequent interval, and the Quantum 4000E also has a remote download function, enabling the GPS data stored in the collar to be wirelessly transmitted between the collar and researcher. The benefit of this new technology is that the animal does not need to be repeatedly captured to retrieve the GPS data.Daytime searches are also undertaken using the UHF receiver to locate the individual and locations of daytime denning and latrine sites. The location of each den site is recorded using a hand-held GPS. Data downloaded from the GPS collar is then imported and mapped using computer software program ARCGIS (geographic information system), to overlay the data points onto aerial photography.Results demonstrate that threatened species will utilise rehabilitation areas post mining. The data presented will be used to develop a greater understanding of threatened species ecology in and around rehabilitated areas, which will assist in the planning and design of native forest rehabilitation areas.CITATION:York, P, 2014. Mt Owen Mine spotted-tailed quoll study, in Proceedings Life-of-Mine 2014 , pp 591–596 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

A survey of leaching systems for the dissolution of gold has been undertaken and their advantages and disadvantages evaluated both from their effectiveness at leaching and their compatibility with carbon- in-pulp (CIP) and resin-in-pulp recovery. In the near future it is almost certain that cyanidation in some form will remain the leaching system of.choice although economic and environmental pressures could see the introduction of other leaching systems particularly for treating refractory gold ores. The most likely alternative leaching systems appear to be acid chlorine, acid thiourea and ammoniacal thiosulphate. INTRODUCTION High grade reserves of readily recoverable gold ores are gradually being depleted which, inevitably, must create a greater awareness amongst gold producers, of the efficiency and, in some cases, the suitability of present day metallurgical processes for treating low grade, complex and refractory deposits. One of the key steps in the extraction of gold is the dissolution of the metal using chemical reagents which, ideally, should be cheap or recyclable, selective, non-toxic and compatible with down-stream recovery processes. In practice, meeting all these critera is difficult - if not impossible - particularly in view of the stringent environmental impact requirements which must be met Nowadays.

Jan 1, 1982

By T Baumgartl, B Richards

Covers on waste rock and tailings remain the primary choice for closure planning where the purpose is to create an environment where water ingress into reactive material can be controlled and/or prevented. In semi-arid and arid environments, dry cover systems are the preferred option with the design intention to absorb rainfall and to prevent deep drainage. Although the average amount of rain typical for semi-arid environments is relatively low and evaporative demand is high, the seasonal and annual distribution may vary greatly. Rocky substrates are often the only choice for the construction of covers due to economic constraints or availability of suitable materials. While the water holding capacity may be suitable for the application of a dry cover design in arid and semi-arid climates, some of these covers bear the risk of preferential water flow when rain events are intensive or occurring at high frequency. The objective of this presentation is to demonstrate the occurrence of preferential flow through rock containing dry cover systems. A regional classification for the applicability of dry covers is attempted to delineate those regions of Australia where the characteristic of the rainfall pattern increases the risk of failure for dry cover designs. CITATION:Baumgartl, T and Richards, B, 2016. Rainfall patterns rather than climate classification control cover design for closure, in Proceedings Life-of-Mine 2016 Conference, pp 89–92 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Kesser Z, Vincze T

The Western Mining Corporation mining lease on the Bendigo Goldfield measures 5krri x 18km with more than 20 anticlinal folds parallelling th long north-south boundaries. Numerous closely spaced shafts and extensive underground workings on the reef lines along the folds flooded with groundwater following the progressive abandonment of the field. Preliminary water sampling and assessment demonstrated that a major dewatering programme and acceptable disposal methods were necessary to dewater interconnected old workings in areas of interest prior to any underground work taking place. A field wide geohydolic investigation was undertaken to establish geohydraulic parameters, groundwater recharge rates and water qualities. Data from the field investigation together with estimates of the volume geometry of the submerged workings as obtained from old mine plans, production history, and limited pump testing results were used with an appropriate analytical model to obtain estimates of water discharge rates required to reach various dewatering targets. Water disposal options were limited by relatively high salinities, arsenic levels, contained hydrogen sulphide, and the mine locations within the urban areas surrounding Bendigo. Direct disposal to the surface drainage system could not be considered, treatment to acceptable discharge standards was not economically feasible, and it was necessary to adopt a strategy of collection, containment, and evaporation.

Jan 1, 1988

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