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By Beeforth C. G

The use of Non-Linear Programming to obtain improved schedules of future activity in two specific cases of mining and treatment of minerals is described. The two cases were (i) reclamation of gold, uranium and sulphur from old surface tailings dams and, (ii) underground mining of gold. The method used an augmented Lagrangian device to reduce a constrained Non-Linear Programme to a sequence of unconstrained hill- climbing procedures. The main advantages of the method appear to be those of (a)flexibility of modelling of industrial characteristics and constraints and, (b) reasonably modest computation times.

Jan 1, 1977

By Medhurst TP, Trueman R

The aim of the paper was to model numerically some aspects of the extraction of coal pillars by split and fendering. A two-dimensional elasto-plastic plane strain model with strain softening and interface mod- elling was used. The model was able to simulate the improvement of conditions experienced in lifting from the fender, when the roof adjacent to the fender has caved. In contrast, when a stook was left, providing support to a span of uncaved roof, the model pre- dicted the fender would suffer considerably more de- formation and strain.

Jan 1, 1992

By Freeman NV

The concept of an in stream analysis probe was developed at The Zinc Corporation (now Z.C. Mines) in the late 1960's and commercialised quite rapidly, by Phillips and then AMDEL, as an alternative to the established centralised systems (Courier, etc.). The developments which have taken place since that time are reviewed and current procedures and performance are described. An audit of the system, recently undertaken by AMDEL, has highlighted areas where improvements can be made. In 1988 the ISA system will become an integral part of a substantially upgraded process control system.

Jan 1, 1988

British Coal's Selby Complex is the newest producing mine in the United Kingdom. The reasons behind its origins, planning and design are explained. Some detail is given of equipment used, with the emphasis being placed on the unique features of its layout. The entire project has been planned and constructed over many years and the design has consequently changed, principally in response to the geology of the coalfield and improving technology. In spite of many totally unexpected difficulties, the mine, which is not yet in full production, has the highest productivity in the United Kingdom.

Jan 1, 1991

By J Pearce, M Barteaux, S Pearce

The prediction of how waste materials will evolve geochemically within waste storage facilities has been the subject of hundreds of thousands of hours researched by geoscientists globally. Despite the quantity of research there are a number of significant areas of uncertainty that remain as partially resolved issues. One of the most significant issues is the applicability of scaling laboratory test results to field conditions, and the use of laboratory data for predictive calculations to determine geochemical evolution of waste materials in the field. This issue has arisen predominantly as a result of the relative paucity of field monitoring data from waste rock storage facilities (WRSFs) and the fact that laboratory test methods are not typically linked to specific field conditions; rather they are based on generic standardised methods and designed primarily to simulate accelerated weathering conditions that do not relate to field conditions in a linear manner.To address these specific issues the authors have in the last two years made significant progress in the development and deployment of advanced field monitoring equipment within numerous WRSFs. O’Kane Consultants (OKC) has previously reported the findings from data collected from these monitoring installations in a number of papers presented throughout 2013–2014. This valuable site data has subsequently been used by OKC as the basis to design and engineer advanced customisable site-specific kinetic leach columns at OKC’s geochemistry research laboratory. These columns represent an important advancement in kinetic column assessment methodology as they have been designed to replicate the field internal conditions within waste facilities.Key features of the columns include their capacity, size and technical specifications; including fully programmable solenoid-controlled air supply with variable flow and pressure control and in-line heating option, automated temperature control and monitoring, automated oxygen consumption and carbon dioxide production monitoring, and soil moisture/matric suction monitoring.This flexibility of the design not only allows for more accurate field-based assessment of pyrite oxidation rates (POR) but also assessment of the potential effectiveness of waste management options such as deposition within a reduced oxygen environment, for example, as simulations of reduced net percolation rates or oxygen ingress rates can be accommodated.CITATION:Pearce, S, Pearce, J and Barteaux, M, 2015. Advanced customisable leach columns – a new kinetic testing method to simulate site-specific conditions, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 137–144 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

Coal Mining machinery has undergone enormous changes in design and complexity of controls in the past 10 years. Specialised, high productivity equipment has been manufactured in Australia, in sufficient volume, to satisfy the local mullet needs.Local manufacturers face greater challenges from overseas competition, as well as increased customer demands to improve machine performance, productivity, quality, reliability and safety. In order to meet these demands now and in the future, it will be necessary to review work practises, and restructure production and quality systems to incorporate the latest principles and philosophies.

Jan 1, 1991

The Prospect to Pipehead Tunnel is a component of the Sydney Water Board's multi-million dollar Drinking Water Quality Program to improve the quality of Sydney's potable water supply to meet revised national health guidelines. The tunnel project involves the construction of seven kilometres of 3.9 metre diameter machine bored tunnel which is to be lined with a three-metre diameter steel liner. The paper describes the fully integrated planning and design approach and management technique used to enable this major project to proceed to meet the requirements of a tight construction program.

Jan 1, 1993

By Hunter T. C

The wirebar furnacing and casting facility commissioned in 1970 at Copper Refineries Pty. Ltd. (CRL), Townsville, comprising a 70 tonne/ hour ASARCO shaft furnace and a Walker type casting wheel, contained several unique design features. Since commissioning, effort has been directed at improving metallurgical control of the casting process. This has resulted in the identification of optimum mould lubricant properties and the use of continuous on-line measurement of molten metal oxygen content. Casting defects such as cracks and surface porosity are readily explained and controlled using these techniques.

Jan 1, 1977

By Dugan K. J

Mine operators are currently in a situation where market forces are acting to reduce profit margins and at the same time, regulatory bodies are insisting on improved mine safety and stability. This means that ground support must be made more cost efficient while maximising operator and equipment safety.A key aspect of ground support efficiency is the 'in the ground' performance. This paper discusses the factors that influence the way rock bolts and cable bolts perform. It highlights the need to know how support efficiency varies in different ground conditions.

Jan 1, 1992

By L Nagy, K P. Juhasz

The authors were engaged to optimise a traditional rebar cage reinforced concrete segmental lining by means of finite element analysis (FEA) using macro synthetic fibres for the Shanghai metro extension. The aim of this study was to reduce or entirely replace the original steel reinforcement of the segmental lining, in order to make the precast production process faster and more economic. The outer diameter of the tunnel was 6200 mm, the thickness of the segments was 350 mm.The numerical calculations were performed by Atena Finite Element software, which is based on the combination of Menétrey-William and Rankine failure surfaces on the compression and tension sides respectively. The effect of the macro synthetic fibres was modelled as tension stiffening on the tension surface.A one-to-one full scale model of an assembled tunnel ring using the original reinforcement cages was tested at Tongji University in Shanghai, July 2013. The ring was tested to differing load levels where load and displacement were measured until failure. The author’s first step was to calculate the real displacement characteristics of the original reinforced concrete (RC) ring, then calculate the numerically modelled version, so as to compare them. The material parameters of the concrete and rebar used had been determined through basic material tests conducted at the Tongji University. (Bi, Liu and Wang, in press).The numerical modelling undertaken has shown good correlation with the full-scale physical test results. Optimisation of the lining reinforcement was achieved through the addition of fibres, resulting in a substantial reduction of the steel rebar cages. Several results have been computed with the numerical model using different dosages of macro synthetic fibres, showing that the mass of steel reinforcement could be reduced by 50 and 75 per cent respectively.CITATION:Juhasz, K P, Nagy, L and Winterberg, R, 2014. Full-round numerical modelling of a macro synthetic fibre reinforced tunnel boring machine tunnel in the Shanghai Metro extension, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 477–484 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By T Clemens, D Trumm

Adopting environmentally acceptable practices in New Zealand is a crucial requirement for mineral wealth development. Recent planned expansions in the coal and gold industry have increasingly placed mining in the media spotlight. A lack of appropriate standard environmental guidelines has resulted in inconsistent responses and assessments of current and proposed mines. These inconsistencies have lead to delays in decisions on developing economic mineral deposits that may have only minor short-term impacts, and have also allowed unacceptable environmental management practices to continue elsewhere. A research collaboration between CRL Energy, Landcare Research, University of Canterbury and University of Otago aims to provide regulator groups and the mining industry with a unified approach to the requirements of the Resource Management Act 1991,the legislation that largely drives the nationÆs environmental policies and guidelines. The tangible outcome of this research program will be water quality and impact management guidelines integrated into a decision-making framework. The result of this unification will assist in the development of viable mineral deposits and minimise environmental impacts. The framework will be derived from a synthesis of three objectives. Objective 1 identifies potential water quality impact. This objective is based on a targeted geochemical study of the lithology and waterways of the West Coast and Southland regions. Objective 2 categorises the degree of impacts on the ecology of receiving aquatic ecosystems and determines the processes that drive aquatic ecosystem recovery. Objective 3 identifies best strategies to sufficiently manage impacted ecosystems, and to prevent future unacceptable impacts. Wide consultation with representatives of the mining industry and regulator groups will occur frequently during the development stages of the framework. It is anticipated that this multidisciplinary approach will provide a robust and coherent, standardised system that will assist in achieving industry and environmental targets.

Jan 1, 2004

By A K. Ghosh

"Inrush of water is always an issue, especially for mines located in heavy rainfall areas. Nowadays, mining companies and research institutes have developed many advanced technologies for study and analysis of hydrological processes. In this paper, an advanced method is introduced, which uses the Shuttle Radar Topography Mission Digital Elevation Model (SRTM DEM) data in the Geographical Information System (GIS) platform to simulate the stream distributions around two specific mines: Super Pit and Griffin coalmine in Western Australia. The impact of this approach is important because it reduces the time and economic cost by creating a high spatial resolution hydrological map in the specific areas. The study identifies the flow path of the run-off water, which helps in adopting a suitable water management plan surrounding the case study mines. The results match with the ground reality. Based on the results, the stream structure around Griffin coalmine is more complicated than that of Super Pit. The bifurcation ratio and drainage density are computed to estimate the subsoil permeability characteristics of the two mines. Recommendations have been put forward to prevent and reduce the potential risks of water accumulation around the open pit mines.Citation:Ghosh, A K, 2016. Application of Shuttle Radar Topography Mission Data in Hydrological Analyses of Super Pit and Griffin Coal Mine, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 162–169 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By Y Yang, J Skrypniuk

The Jinfeng mine is Sino Gold's flagship project and is the second largest gold mine in China. Sino Gold Limited (SGL) holds 82 per cent equity in the Sino-Foreign joint venture Sino Guizhou Jinfeng Mining Limited (SGJML) with a Chinese partner. Jinfeng is located in a relatively remote site in southwestern Guizhou province. The orebody is considered to be the largest known Carlin type deposit in China. Jinfeng Plant has the world's third largest BIOX« bacterial oxidation facilities (790 t/d), treating highly refractory concentrate generated from crushing, semi-autogenous grinding (SAG) and ball milling and bulk sulfide flotation operations. The Jinfeng Plant construction started in February 2005, commissioning was completed in April 2007, and commercial gold production was achieved in September 2007. This paper describes the successful operations of Jinfeng Plant over the last two years. The key events of the project development are described, from the project background and process design, through to the commissioning and achieving design mill throughput of 3600 t/d resulting 180 000 ounces of gold per year. Process aspects of the BIOX« and carbon-in-leach (CIL) operations over the last two years are discussed which illustrate a very high BIOX« oxidation rate (more that 97 per cent) and excellent CIL recovery (more than 96 per cent). The management of the Jinfeng plant CIL tailings detoxification and filtration is described, and Jinfeng has became the first BIOX« processing plant to have achieved dry stacking of detoxified and pressure filtered CIL tailings. Current efforts to recover cyanide from CIL detoxified solution and the achievement of a zero discharge site water balance are also introduced. Many improvement projects have been made over the last two years which have culminated in a 15 per cent increase in mill throughput over the design and BIOX« CIL recovery increasing from 92.5 per cent to 96 per cent. Significant operating cost reductions from lowered of acid, lime and cyanide usage through process modifications and technical innovations are discussed.

Jan 1, 2009

By B Belle

In a deep, gassy predrained coalmine, ventilation and goaf drainage systems act as critical controls to manage longwall (LW) panel return gas levels. The goaf capture efficiency of most LW panels ranges from 45 to 85 per cent based on the gas domain at respective workings. Recent operational experiences have indicated that 50 m goaf hole spacing is optimal for management of high production retreat gassy LW panels, where the probability of goaf hole failures are frequent. Due to the horizontal stress direction geotechnical issues, goaf hole failure just behind the LW face is a recurring challenge resulting in significant and immediate increases in LW panel return gas levels. This paper presents a successful implementation of an innovative LW tailgate (TG) road cut through seal goaf fan/venturi system. The system incorporated a 17' (400 mm cased) hole drilled to 320 m deep in a perimeter roadway on a retreating LW TG road drawing the working seam horizon goaf gas behind the perimeter of seals. The surface goaf fan/venturi system was aimed to safely exhaust the LW deep goaf gas and thus withhold the goaf stream spillage to TG drive area and reduce the panel gas load by controlled operation of the system using continuous monitoring of CH4, CO and O2 levels. This control philosophy was made operational without impacting the use of the perimeter inbye ventilation shaft used for mine cooling and providing additional ventilation dilution capacity. The instantaneous reduction in TG gas levels of up to 0.3 per cent was observed even when the LW was 300 m away from the c/t seal goaf hole. Success of this concept TG seal goaf gas control system used even when the LW was 1300 m outbye has become an inventory of additional control for future deep and long LW blocks. This paper attempts to share the design process in addressing other risks and desired outcomes in managing the LW gas levels.CITATION:Belle, B, 2015. Innovative tailgate mobile goaf gas management in two gate road longwall panels – concept to implementation, in Proceedings The Australian Mine Ventilation Conference, pp 31–40 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By Mason P, Waller C

The Phase I electrowinning system at KCGM's Fimiston Operation utilised the well proven technology of electrowinning precious metal values onto steel wool followed by calcining and direct smelting to bullion. The above process, while reliable and successful, was to some extent labour intensive. The Williams Mine in Ontario, Canada had published conditions under which precious metal values are electrowon onto woven stainless steel and directly removed using high pressure sprays. The current paper describes the testwork which was carried out to check the applicability of the Williams criteria to KCGM eluates arising from the elution of highly loaded carbon from the calcine circuit and lowly loaded carbon from the float tails circuit. Information is also given on the commissioning and operational experience which occurred.

Jan 1, 1996

Longwall mining operations have been in place in Australia since the early 1960s. This mining method is currently used to extract the bulk of coal obtained from underground mines in Australia (CSIRO, 2010). Despite the high tonnages extracted the expected utilisation of much equipment remains relatively low. To some extent this level of utilisation is influenced by the variability in conditions inherent in the mining process. This variability in production rates presents challenges to those attempting to design a coal clearance system. The difficulty is to design a system that has sufficient capacity to support production, without over capitalising or incurring high operating costs. The need to allow for a series of largely unplanned events in the design of a coal clearance system makes simulation modelling an ideal technology to employ. Simulation modelling is a methodology that allows a system with interacting components to be modelled over time, while explicitly taking into account unplanned events that may disrupt operations.This paper discusses how dynamic simulation models have been used to assist in the design of coal clearance systems. Typically this type of modelling has been used to look at the likely profile of production rates from the Longwall shearer and to determine how well various proposed combinations of belts, bins and stockpiles would support production.

Sep 26, 2011

By P Navarra, R Kuhne

Dynamic simulation (discrete event simulation) is the preferred methodology to evaluate the impact of dynamic aspects of processing plants on the overall plant capacity. This tool can be used to: identify bottlenecks in the plant,justify upgrade and expansion projects by evaluating their impact, oroptimise maintenance and operating practices without disrupting the operation. Iron Ore Company of Canada's (IOC) pelletising plant is a complex operation because of multiple products, varying equipment capacity and shifting bottlenecks. Furthermore, with extensive capital requirements for projects and long lead times, a high level of confidence in project outcome is required. Therefore, a model of IOC's pelletising plant in Labrador City was constructed in 2007 by a joint IOC and Hatch team. The model includes both operational and metallurgical aspects in order to better capture the complexity of IOC operation. In this paper, the justification, boundaries, and functionality of the model are described. A comparison of simulation results to historical plant operation is given. It is observed that projects have interactions and that the benefits of combined projects are not equal to the combined benefits of the individual projects. Projects can have synergies that result in greater benefits when combined or can have overlapping benefits that result in lower benefits when combined. The power of the proposed modeling exercise lies in the ability to assess the impact of projects on overall performance.

Jan 1, 2009

How often does one hear that a recent feasibility study was not a success? Alternatively, when scope of the feasibility study was sent out to tender there was a large discrepancy in tendered prices. If the tendered prices were to be compared to the consumer market, for instance the purchase of a car, where the concept is transport in a controlled and safe manner, prices vary by large factors, but then so do the specifications. In the case of a feasibility study, prices should be within a tighter margin as the tenderers are all quoting against the same concept and specification. Why do these discrepancies occur? Price discrepancies will in every likelihood be attributed to two main factors; one, the perceived amount of work and two, the ability of the bidder to carry the risk associated with the feasibility study. It is, therefore, important that the scoping of the feasibility study covers the detailed requirements as clearly as possible stating what level of accuracy is required. The feasibility study is one of the first activities in the life of a project. The study, like the project it is investigating, is subject to the constraints of time, cost and quality. Its primary objectives are to demonstrate the viability of a project within the outlined scope and constraints.

Jan 1, 1998

By C Chen, W J. Bruckard, F R. A Jorge

The base metal industry mines and processes hundreds of million tonnes of ore per annum to produce saleable products and large tonnages of waste by-products such as tailings. These ores usually contain less than 1 wt per cent of toxic elements (As, Sb, Bi, Cd, Se, Te, Hg, etc), which are subsequently treated with the other components in the ore during the production of concentrate through to saleable metal products. The deportments of minor elements across the various unit operations of a process flow sheet do not normally receive the attention that the major elements receive. However, these minor elements can have a major influence on the quality of the products as well as an economic and environmental impact. Therefore, a high degree of control over their deportments is a key step in reducing their dispersion in the biosphere. Ongoing work at CSIRO has been examining minor element deportments across unit processes used for smelting and refining and the options for early removal of minor elements, as well as methods for safe disposal of some toxic elements. This paper provides an overview of the R&D activities undertaken at CSIRO to develop tools and methodologies for improved management of minor elements during the processing of sulfide ores.

Jan 1, 2006

By H R. Phillips

The ventilation and refrigeration design of underground mines is an important aspect, when new or existing mines are considered and places a great responsibility on engineers tasked to do so. The current trend for both local and international underground mines is to extend their search for valuable ore reserves deeper below surface. In South Africa, the predictions are that about 40 kt of actual gold still lies in situ, ready for extraction. As mines extend their search for minerals of economic value deeper and deeper into the earthÆs crust, ventilation and refrigeration aspects of such mines become more prominent than before. The planning and design of the required ventilation and refrigeration within these mines, over their expected lifetime is important including the practical implications of such designs. Technology changes and improvements need to be incorporated into ventilation and refrigeration designs, where possible and advances in this specialised field explored. This paper explores ventilation and refrigeration design aspects within the underground mine sphere. Aspects such as mining depth, virgin rock temperature (VRT), mining methods, and different cooling applications available including ventilation supply are reviewed in design applications. Heat generally becomes a significant aspect to counter in these mines and they are not always necessarily deep mines.

Jan 1, 2005