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By J. P. Ducarme

Numerous fatal/nonfatal accidents involving underground workers struck by powered machinery occur yearly, with continuous miners and roof bolters involved in the majority of these accidents. In an attempt to reduce these accidents, researchers at the the National Institute for Occupational Safety and Health (NIOSH) Pittsburgh Research Laboratory conducted studies of operator interactions with the motions of continuous mining machines and roof bolter boom arms. These operators generally perform their tasks in close proximity to the equipment in confined workspaces, often employing awkward postures. Since experiments with human subjects using the actual equipment were not feasible due to safety concerns, researchers opted to conduct controlled experiments in laboratory settings. Utilizing motion capture technologies and computer simulations, the studies collected data on equipment and operator movement in a range of seam heights and working postures. This article details the results of these studies to examine operating speeds based on usage and seam height.

Jan 3, 2010

The validity of a steady state assumption made by Adams and Nicol (1986) in the modelling of the elution of gold from activated carbon was investigated. It is shown that the accuracy of the steady state approximation is dependent, not only on the magnitudes of the solution flow rate and reactor volume, but also on the lumped elution rate constant. Under the experimental conditions used by Adams and Nicol (1986) the steady state assumption was inaccurate. This could be circumvented in this instance by applying a rigorous general model which accounts for unsteady state behaviour in the solution and in the activated carbon to the experimental data.

Jan 1, 1997

By G. Laing

On scheduled commissioning and effective operation of a solvent extraction circuit relies on getting the design of both the core contact equipment and the peripheral plant right. Experience has shown that poor performance of new plants is frequently a result of ?utility? systems that do not match the requirements of the circuit, rather than the mass transfer equipment itself. Both the operator/owner and designer need to understand the ?complete requirements? for the circuit to get the balance of the design right. This paper reviews generic issues, frequently overlooked or altered during cost-cutting exercises, which have a significant impact on plant performance.

Jan 1, 2002

By A Parbhakar-Fox, B G. Lottermoser

Management of solid mine wastes, particularly waste rock, requires careful planning to reduce the likelihood of sulfide oxidation, and generation of acid rock drainage (ARD). Waste management strategies must focus on obtaining a thorough understanding of the environmental characteristics of future waste rock materials. In this study, a waste management strategy for characterising underground waste rock was developed at a polymetallic underground mine in western Tasmania to determine which materials were appropriate for surficial placement. The criteria for surficial placement set by the regulator were that materials had to be non-acid forming and non-metalliferous. A range of cost-effective field-based tools, mineralogical assessments and mineral chemistry techniques were used on a suite of representative drill core material to determine an appropriate waste management strategy. Ultimately, a modified geochemistry–mineralogy–texture–geometallurgy (GMTG) approach was designed, whereby geoenvironmental focused logging and simple prescreening tools such as paste pH and sulfur analyses were used at stage-one; routine acid base accounting and leachate tests at stage-two; and validation tools including X-ray diffractometry and laser ablation inductively coupled plasma-mass spectrometry (ICPMS) at stage-three. This approach should be considered for other mine sites at early and operational life-of-mine stages with similar deposit characteristics, to ensure correct screening and placement of potentially hazardous waste materials in suitable above-ground waste repositories or mined-out mine sections.CITATION:Parbhakar-Fox, A and Lottermoser, B G, 2017. Effectively linking mining geology with waste management – a case study from western Tasmania, in Proceedings Tenth International Mining Geology Conference 2017, pp 117–126 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By A. J. Farstad

Recent advances in microcomputer technology have opened the way for systems which can track the location of underground mining personnel from the surface. A computerized system has been designed which is capable of not only tracking the location of the miner but also of monitoring underground parameters, communicating between work stations and sounding alarms when underground conditions are judged to be unsafe. For the system described herein, the locations of the underground personnel are detected by a network of underground terminals which routinely emit RF pulses to interrogate miniature transponders worn by the miners. Each transponder is uniquely programmed to delay its response in such a way that the RF terminal can identify the individual transponders by the time slots in which the responding pulses are received. The underground terminals are then interrogated by the host computer on the surface which keeps a running account on underground mine conditions and personnel. The underground portion of the system is designed to operate even during mine emergencies, deriving its power from rechargeable battery supplies which are float charged during normal operation. Nine mines were visited on this program and the industry reaction to the system was generally favorable. By slanting the system design for daily use in the mine, the chance of its acceptance by the industry is enhanced. Furthermore its likelihood of being operational in the event of an emergency is significantly increased.

Jan 1, 1981

By Paulo F. T. Sachs

ERP systems have been widely implemented nowadays in several industries. However, ERP was originally designed to fit former MRP and MRP II users, and most of the ERP research has been focused on discrete manufacturing . On the other hand, process industries ? and mining in particular ? present many peculiar characteristics, which are difficult to comply with ERP systems standard functionalities. Again, very limited research has been developed covering enterprise management systems in mining. The objective of this paper is to identify, through an explanatory study that includes a case study methodology, how ERP systems manage the functional areas of the mining industry, and how they fit into the mineral value chain IT requirements. A secondary objective is to identify the gaps between ERP?s functional capabilities and the mining industry business requirements, and to point out the perceived benefits they generate to the companies.

May 1, 2004

By Maya Kamenetsky, Khoi Nguyen, Natalee Bonnici, Steve Walters, Claire McMahon, Julie Hunt, Ron Berry

"The analysis of meso- and micro-scale textural attributes has been undertaken on ore samples from the Ernest Henry iron oxide-copper-gold (IOCG) deposit in NW QLD. Quantified textural data including grain size, shape and mineral association have been extracted from classified images of core with the aim to better predict potential mineral processing behaviours such as comminution, liberation and flotation. Data have been extracted from images of intact core at meso- and micro-scales using high resolution continuous images collected using automated core-logger technology, SEM-based and optical microscopy platforms.The results of this study will show examples of quantified size, shape and mineral association data from meso- and micro-scale classified images. Analysis of the data shows that there are domains of variable grain size and mineral association that can potentially be related to crushing and liberation behaviour. The trends that are observed at the drill-core (meso-) scale are consistent with those at the micro-scale. The results from the micro-scale analysis show that the domains defined at the core-scale have clearly different chalcopyrite sizes and shapes as well as variable bulk mineralogy.INTRODUCTIONInnovations in technology have allowed automated extraction of information about mineral shape, grain size and mineral association, i.e., texture, from meso- and micro-scale images of intact rocks. The overall aim of this research is to investigate trends in quantified textural data that can potentially give an early view of processing parameters such as predicted grind size and liberation behaviour."

Jan 1, 2009

By R. J. Durrheim

The seismicity of the Witwatersrand Basin and Bushveld Complex has been analysed, revealing significant differences in source and damage mechanisms. A comparison of mining taking place at similar depths and extraction ratios indicates that the seismic energy release rate is considerably lower in the Bushveld Complex. Technologies introduced in the past decade to manage the risk of rockbursting are reviewed and assessed. These include geophysical methods to detect hazardous structures ahead of mining, new mining layouts and support systems, and the mechanization of in-stope processes. Despite important differences in geology, in situ stress, mining layouts and methods, there are many opportunities for the reciprocal transfer of knowledge, experience and technology between the gold and platinum mining sectors to improve the management of the rockburst risk.

Jan 1, 2005

By S. Shaw

There is an increasing requirement for mines to meet a certain minimum criteria for sustainability within the context of the physical environment, ecosystem and socio-economic system in which they are located. The mining industry has wrestled to develop methods for assessing the ‘sustainability’ value of a mining project and indicators of ‘sustainability success’. A methodology for the evaluation of sustainability of a mining project using the Multiple Accounts Analysis (MAA) system was developed. The MAA is a platform for engagement of stakeholders and for the assessment of site-specific alternatives based on both qualitative and quantitative indicators of success.

Jan 1, 2004

By Clark F. Grain

These investigations were undertaken as part of the Bureau of Mines program for the development and evaluation of high temperature nonmetallic materials. This report consists of thermal expansion and phase inversion measurements by high-temperature X-ray diffractometry on the principal oxides of beryllium (BeO), calcium (CaO), titanium (TiO2 ), zirconium (ZrO2 ), hafnium (HfO2), and thorium (ThO2); all were high-purity commercially available oxides. Thermal expansion values were calculated from unit cell dimensions measured at selected temperatures. Expansion was determined parallel to each major crystallographic axis for the anisotropic oxides: BeO, TOi2, ZrC2, and HfO2. Combined random and systematic errors in the thermal expansion values are considered to be less than 3 percent of the total expansion at 500° C. and approximately 2 percent at 1,000° C. No hysteresis in the expansion curves was noted between heating and cooling cycles. The Bureau's values were compared with published expansion measurements obtained by X-ray diffraction, dilatometric, interferometric, and telemicroscopic techniques. For anisotropic oxides, average linear expansion values were calculated from the volume expansion.

Jan 1, 1962

By George A. Savanick

The objective of this research is to develop a method for measuring the tensile strength at the interface between minerals in rock. These measurements reflect the strength of the attractive forces operating at crystalline interfaces in rock. Since these forces act in opposition to the forces set up in various rock fragmentation processes, measuring their strength may help in designing more efficient methods of rock fragmentation. The method developed for measuring the strength of intergranular adhesion in rock involves separating a bicrystal from the rock and determining the tensile strength at its solid-solid interface. This technique has been successfully applied to the study of quartz-feldspar interfaces separated from massive pegmatites, graphic granite, and the Rockville granite, yielding average tensile strengths of 5.86, 8.62, and 10.65 meganewtons per meter squared (MN/m2) (850, 1,250, and 1,524 psi, respectively). The data this technique provides indicate that the members of these bicrystals are strongly adherent. Examirtation of bicrystals broken at the crystalline interfaces indicates that the bonds responsible for this adhesion operate over only a portion of the interfacial area. This work conclusively demonstrates that tensile strength tests can be conducted on small selected areas; for example, grain boundaries in rock. The small-scale zones of strength or weakness determined in this way can be related to the overall strength of the rock.

Jan 1, 1972

In North-West Nelson the Riwaka Complex, a linear basic intrusive complex, is exposed for approximately 45 km. Some 500 km south, across the Alpine Fault, a linear zone of similar but less well known basic intrusives that may be correlatives of the Riwaka Complex is exposed discontinuously for about 80 km. The Complex was emplaced at several centres along a major tensional fracture zone that developed in upper Carboniferous to Lower Permian time. This fracture zone probably formed in response to the development of a west dipping subduction zone that gave rise to the Permian volcanic arcs in east Nelson and western Southland. The Riwaka Complex contains three rock suites. The Fractionation Suite, characterized by cyclic mineral layering and small scale cumulus banding is the largest and is divided into the Ultramafic, Hornblende and Plagioclase Series, each of which is subdivided into several units. The Cumulus Gabbros represent a restricted but important suite of unusual composition, while the third suite is the late phase Diorite Suite. Except in the lower units of the Ultramafic Series sulfide mineralisation is widespread. Pyrrhotite is the dominant sulfide with lesser chalcopyrite pentlandite and pyrite. Four significant zones of sulfide accumulation are recognised and discussed in some detail. Evidence suggests that the primary magma from which the Riwaka Complex was derived was sulfur deficient. It is concluded that the sulfur content of the Riwaka Complex was derived from assimilation of sulfur rich wall rocks during intrusive processes.

Jan 1, 1980

By John Lindsay

"Although diamond mining is a relative newcomer to the Canadian mining industry, with the first diamond mine coming on stream in 1998, Canada is already a significant producer of high quality diamonds. This paper will review diamond production trends and highlight some of the projects currently under development, which have the potential to enhance Canada’s role as a significant diamond producer.Diamond recovery plants generally incorporate well-established mineral processing and recovery techniques, with issues such as product security, cut-off sizes, and diamond preservation becoming important considerations when developing process flowsheets. A diamond processing plant must achieve three key objectives, namely:• Liberation of the diamonds from the host rock;• Separation of the heavy minerals, which include the diamonds, from the host rock;• Recovery of the diamonds from the heavy mineral concentrates.Processing technologies and equipment commonly utilized in diamond processing plants will be reviewed and some of the significant issues associated with each option briefly discussed.Typical process flowsheets will be presented.Finally, an overview of De Beers’ Victor diamond project, located in northern Ontario, will be provided. This potentially significant diamond producer is currently at a pre-feasibility stage of development.DIAMONDS IN CANADAWorld Diamond ProductionCommercial diamond mining commenced in earnest with the discovery of the Kimberley diamondfields in South Africa in the late 1800s, and this resulted in a dramatic increase in the supply of diamonds. As can be seen from figure 1, world diamond production, mainly from South Africa, Angola, Congo, and Namibia, remained relatively constant through the early 1900s until the development of the large Russian kimberlite pipes in the 1950s. Production increased again in the 1960s and 70s with the development of the Botswana mines, but the most significant increase in global production came from the Argyle mine in Australia, which came on stream in 1983 and produced a peak of almost 43 million carats in 1994, representing approximately 40% of the world market. Production from Argyle has since fallen-off as grades have declined and the strip ratio has increased with the deepening of the open pit."

Jan 1, 2003

By George A. Morgan

The successful expansion of crude oil production begun in late 1977, led to promising development of the nonfuel minerals sector. Although actual production of nonfuel minerals was limited both in variety and in percentage of output on a world scale, the potential for expansion with a rapidly developing infrastructure was significant. The energy base was expanding with construction of two new hydroelectric powerplants in addition to the existing plant near Edea. The Song Loulou plant will have a 240-megawatt capacity, and a hydroelectric plant under construction in the northern part of the country by mainland China will have 72 megawatts of installed capacity. Inflation of between 15% and 20% resulted in a real gross domestic product (GDP) of $2.8 billion2 in fiscal year 1980 (July 31 to June 1), up 6% from that of the previous fiscal year. Petroleum became the leading export item in terms of value, surpassing coffee and cocoa exports. Mineral exports as a whole increased eightfold in value, mainly because of oil sales. Oil exports also caused a reduction in the trade deficit by nearly one-third, and the Government expected its 1980-81 budget to be balanced at $1.17 billion. The Port of Douala accounted for about 8 million tons of cargo, or 93% of total maritime traffic for Cameroon. Expansion plans for the port call for an initial increase to 5 million tons, and a cargo handling capacity of 7.5 million tons in 1985 and 10 million tons by 1990. The Port of Victoria will gain importance with the startup of an oil refinery. The country's third seaport at Kribi was used solely for timber shipments, and capacity at the Port was to triple by 1981. The Government operated its own shipping line with six oceangoing freighters. France was the dominant trading partner, accounting for 25%

Jan 1, 1982

By W. F. Visser

The growing availability of information and data analysis capabilities of recent years provides new opportunities for improving the performance of mining operations. By using real-time measurements and artificial intelligence, it is possible to respond faster to changing conditions, while accurate and timely information permits rapid evaluation of changes and fast business improvement decisions. This article presents a blueprint for alignment of systems, organizational design, and management practices to leverage these developments in performance-driven operations management in mining and mineral processing. The first component of the blueprint is a performance framework with a system of key performance indicators for production control that can be used across organizational levels. This system places improvement at the core of management activities, giving greater importance to improvement skills at lower organizational levels, so companies can leverage available information for improving operational control. Secondly, the blueprint defines an organizational structure that strengthens performance improvement with technological and change management capabilities. Finally, the blueprint proposes alignment of management practices, covering the optimization of short-interval controls, the application of an improvement project portfolio management system that determines the ownership of improvement projects, and the coordination of controls across the organization. This combination of systems, organizational design, and management alignment supports rapid decision-making at the right organizational level. Introduction of the presented blueprint for operations management enables mines to leverage the developments in information and analysis capabilities to improve the performance of operations.

By A Watson

We tend to overestimate the volume of water used to process ore and the evaporation from tailings and heap leach stockpiles. During mine operation, a significant portion of the water collected from onsite water management systems is consumed and recycled by ore processing and lesser portion discharged to the environment. When mining and processing cease, however, the mine site water balance is altered and the real effort and cost associated with managing and disposing of excess mine-influenced water becomes evident. As these flows can no longer be recycled and may not be suitable for discharge to the environment, the cost of dealing with them can comprise a significant portion of the post-mining liability. The problem of dealing with large volumes of mine affected water has the potential to become worse in the future due to the established trend of lower grades which require more water per unit of mineral processing. As a result, future mines may be expected to have greater water needs and problems than we experience today.This paper discusses various aspects about how water usage changes when a mine transitions from operation to closure based on observations and numerical simulations of made with site-wide water balance models. The intention is to provide general considerations for mine operations in planning for end of mine life and post-mining care and maintenance.

Jan 1, 2009

By Frank M. Vodoklys

This is the final report on Contract H0220049 covering the period from 27 April 1972 to 30 April 1974. The objective of the contract was to develop and evaluate materials and methods to achieve post explosion identification of explosives reliably and economically through the use of phosphor coded grains incorporated into the explosive during its manufacture. A coding system of two spotting phosphors and seven coding phosphors was successfully developed during the execution of the contract. The ability of the coded grains to survive detonation in many different types of explosives was demonstrated and the complete code was extracted from a single 100 micron post-explosion fragment. A method was established for testing grain strength to correlate with field test results and an optical system was designed for extracting the code from the grains. Also in fulfillment of the contract requirements a laboratory method for manufacturing the coded grains was established and ten one-pound samples, each with a different code, were fabricated. Finally, a method was developed for applying a coating of polyethylene to the grains to prevent sensitization of the tagged explosives and the ten one-pound samples were coated and delivered to the Bureau of Mines.

Jan 1, 1974

By Levent Ozdemir, Bjorn Nilsen

For several recent TBM tunnel projects, unexpected ground conditions have been encountered, causing extra cost, considerable delay, and in some cases major claims. Undoubtedly, insufficient and/or irrelevant site investigation and testing are among the main causes of such incidents. The purpose of this paper is to review the main investigations and tests relevant for hard rock TBM projects, with particular emphasis on the considerable development that has taken place over the last few years. Also, guidelines for defining optimum scope and extent of site investigations and testing are discussed, as well as the importance of adjusting the investigations and tests according to complexity of the ground conditions and project type.

Jan 1, 1999

By G. D. Mainwaring, Weng L. W, Lam Y. K.

The first power transmission cable tunnel in Singapore was the 2.6km long undersea tunnel between Pulau Seraya and mainland Singapore, constructed in the1980s. Ten years later, similar concepts were used for the Tuas Cable Tunnel. The tunnel, which includes a 2.2km long immersed tube section, was designed to accommodate 10power circuits of 400kV and 230kV capacity. It is fully equipped with sophisticated control and communication equipment, fire suppressant and life safety systems plus a maintenance vehicle which runs on tracks through the length of the tunnel. The paper discusses the planning, design, and construction of the Tuas tunnel, and the development of these concepts for future tunnels.

Jan 1, 2001

By N. Yamazaki

The supply of clean copper ores, which have high copper concentration and low impurities like arsenic, has declined year by year. Therefore, both mine and smelter sides have to consider how to remove impurities like arsenic. We focus herein on arsenic as an impurity because it is an extremely important issue from the environmental point of view. Approximately 150,000 t of arsenic is input into the copper industry every year. A small part of it is mainly treated in the smelting side. For instance, Ministro Hales Limited, which is a mining corporation in Chile, has performed the calcination process to remove arsenic from ore with high-arsenic content. In the process, flue gas is washed by water, and the final residue is treated by a hydrometallurgical process. Many processes for arsenic removal in various stages have been proposed, and several bottlenecks exist to achieve it. One of the difficulties encountered is getting an assessment of the process, which depends on the countries and/or areas of operation. The standardization of the assessment procedure will be desired in the near future to keep the same environment standards all over the world, and now is the time to start making discussions on this matter. This will be the first step in making an international assessment procedure for arsenic treatment in the copper industry. INTRODUCTION Using the term “sustainable development” without any scientific basis can give people a false sense of security. Engineers and scientists must analyze the total mass flow of energy and materials and estimate local drain on the environment as well as the global impact of a particular industrial activity to ensure sustainability on this planet. The operations of the mining and smelting industries have a strong effect on the environment even if they provide useful materials for human beings. The copper mining and smelting industries have brought about serious environmental problems in the past. For example, the Ashio mine pollution caused big damage to the agricultural sector near the Ashio area in Japan in the late 19th century. One of the most serious problems at that time was SO2 emission because copper ore is sulfide, and the smelting process basically results to sulfur oxidation. The resource balance from a copper smelter in a year, assuming a total production of 16 million tons, can be summarized as follows: discarded minerals, 30 billion tons; sulfur, 16 million tons; iron oxide, 8 million tons; additional smaller amounts of other metals, electricity, and fuel.

Jan 1, 2019