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By D. G. Hulbert, D. J. Oosthuizen, D. de V. van der Spuy

Expert Online, as a software system, is aimed at providing plant operators in the minerals industry with effective training and on-the-job assistance. It incorporates a number of features to achieve this goal, of which the most important is its ability to explain the dynamics of the plant and control system in simple language, mimicking an informed plant expert who has online access to the inner workings of the plant and control system. This is made possible by a novel form of Artificial Intelligence, called the Interpreting Expert System. Previous implementations of the IES were only capable of explaining controller actions. Expert Online will extend this capability to also perform the more difficult task of explaining process behaviour. Expert Online will implement three main processes, namely the accumulation of data from the controllers and plant models, the interpretation, processing and filtering of that data and lastly communicating the relevant information to the user, both as written messages and in other audio-visual forms. Although Expert Online is aimed at the operator, other plant personnel, like supervisors and plant managers, will also benefit from it. This paper focuses on the structural and functional design of Expert Online for implementation on the latest version of Mintek’s open control platform, PlantStar, highlighting advances and additions since the previous implementations of the Interpreting Expert System and concluding with an example illustrating some of the principles.

Jan 1, 2003

By David G. Hulbert, Daniël J. Oosthuizen, Bernard Muller, Daniël de V. van der Spuy

"Expert Online is a software system that makes use of novel artificial intelligence technology, known as the Interpreting Expert System (IES), to mimic an informed expert on a minerals processing plant. Previous implementations of the IES were only capable of explaining the controller actions. Expert Online will also take on the more difficult task of explaining the complex process behaviour to the operator in simple language.The primary functions of Expert Online are to serve as a training tool and an online assistant to operators. However, it is also expected to be of value to supervisors and plant managers.A number of additional features are envisaged, including different operating modes, fault detection, speech synthesis and advanced message filtering. Expert Online will increase the operator’s knowledge of the process and his/her understanding and acceptance of the complex control systems. Users would be supplied with relevant and timeous information required to make informed decisions to ensure smooth plant operation.This paper discusses the structural design of Expert Online for implementation on the latest version of MINTEK’s open control platform, PlantStar, as well as several advances and additions since the previous implementations of the Interpreting Expert System."

Jan 1, 2003

By S Q. Liu, E Kozan

This paper proposes a new multiresource multistage scheduling problem for optimising the open pit drilling, blasting and excavating operations under equipment capacity constraints. The flow process is analysed based on the real-life data from an Australian iron ore mine site. The objective of the model is to maximise the throughput and minimise the total idle times of equipment at each stage. The following comprehensive mining attributes and constraints have been considered: types of equipment; operating capacities of equipment; ready times of equipment; speeds of equipment; block-sequence-dependent movement times of equipment; equipment-assignment-dependent operation times of blocks; distances between each pair of blocks; due windows of blocks; material properties of blocks; swell factors of blocks; and slope requirements of blocks. It is formulated by mixed integer programming and solved by ILOG-CPLEX optimiser. The proposed model is validated with extensive computational experiments to improve mine production efficiency at the operational level. The model also provides an intelligent decision support tool to account for the availability and usage of equipment units for drilling, blasting and excavating stages.CITATION:Kozan, E and Liu, S Q, 2014. An Open pit multistage mine production scheduling model for drilling, blasting and excavating operations, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 329–334 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

The recent boom in the mining industry has lead to some unique challenges in successfully operating processing plants. With high turn-over rates of both operators and technical staff, and many experienced personnel leaving regional sites for city based jobs there is often an onsite knowledge vacuum and this in turn puts pressure on both site training departments and senior metallurgists to provide the relevant skills to the continuous stream of new staff. Frequently both operators and new metallurgists are instructed on a æhow-toÆ basis rather than giving them the understanding as to why tasks are performed and decisions are made. This paper has been written with the plant operator and metallurgist in mind and aims to provide suitable material to be incorporated into a site training manual. Topics have been broadly divided into the following categories: factors that operational staff can control; including pulp density, air addition rate, froth depth, particle size and reagent type and use; factors that operational staff cannot control; providing general information on bubble size, froth stability, pulp chemistry and the mechanical effects of the rotor/stator system; and process improvements. Each topic is discussed with a view to clarifying the key process variables that need to be understood and optimised in an industrial operating plant.

Jan 1, 2009

By D. deV. van der Spuy

A procedure for optimizing the secondary cooling zone of continuous casters is proposed and illustrated by a billet caster example. The procedure consists of quantifying deviations from the required conditions of the secondary cooling zone?as far as temperatures, metallurgical length and reheating are concerned?by means of a ?cost function?. The optimal spray settings are then found by minimizing the total ?cost?. The billet caster examples serve to emphasize the importance of specifying the required conditions in a consistent manner. Some envisaged practical limitations of this approach are discussed.

Jan 1, 1999

"This paper describes an alternative method of vehicle control which uses a micro-processor to control the field current and armature voltage concurrently. The field tests carried out and the conclusions drawn from the basis of the paper.IntroductionIt is generally accepted that the main obstacle to a greater use of electric vehicles is the relatively poor range and performance when compared to alternatives such as diesel and petrol-engine vehicles. Much effort has been applied to the problem of increasing the energy storage density of batteries and considerable improvements are now being reported.Improvements in the efficient use of the stored energy, although unlikely to achieve the necessary increase in range and performance for a widespread acceptance of electric vehicles, can nevertheless make a useful contribution. Because the improvement in efficiency is achieved by a reduction in losses, it follows that the temperature rise in drive-train components is reduced. These advantages, coupled with the increasing cost of energy, make improvements in the efficient use of the stored energy desirable, if not absolutely necessary. To achieve this with the large and rapidly varying loads encountered during the operational use of a vehicle will require a more flexible system of control than that provided by the current limit. This paper describes an alternative method of control which uses a micro-processor to control the field current and armature voltage concurrently.The value of these parameters is selected to supply the power demand at the motor shaft, with the minimum losses in electrical transmission, thus increasing the efficiency with which the stored energy is used."

Jan 1, 1982

By D P. Yang, Yang R. G

The laws of throwing and heaping of engineering blast are important for making use of throwing and heaping of thrown body to form certain shape, such as building dams by directional blast. The article is to apply Ballistic theory of single thrown body to take the throwing course of thrown body as the movement of particle system, and then delimit the total of thrown body into units of thrown bodies, and regard the heaping shape of single thrown body as a perfect triangle, and found a quantitative relation between macro-geometry parameters of perfect triangle and designed parameters of explosives. The theory has been adopted in blast practice and gotten good effects.

Jan 1, 1999

By Hugh P. Nicholson

IN view of the many articles that have been written on the proper classification of mining systems without so far having produced any particular tangible results it might seem that the subject is hopeless of solution. I do not believe that is so, and my intention in contributing the following outline is to present a slightly different viewpoint. Too much attention is often focused on unnecessary details and not enough on general principles. Too much attention and emphasis is often given to the system employed at one particular mine or in one particular district. In addition, names that are entirely misleading are applied to mining systems, and their adoption by the coming generation perpetuates a condition that needs clarification badly. The following classification is the result of several years of practical experience in mining and also several years' practice in teaching the same subject. It therefore represents a broad picture of the entire field of mining systems from the viewpoint of the miner as well as the teacher. It seems that the difficulty in the past has been in reconciling these two viewpoints. The need of such a reconciliation requires no explanation.

Jan 1, 1934

By Dan Jackson

9:00 a.m., June 28, 1983 MR. MORTENSEN: Good morning ladies and gentlemen. Again, it gives me great pleasure to welcome you to another session of the 79th meeting of the Rocky Mountain Coal Mining Institute. The thing again that has always been impressive are the activities that we've had so far. The success in the meetings has been delightfully encouraging to all of our committee people. Please welcome the chairman of the session, Charlie Margolf. MR. MARGOLF: Thank you, Vernal. Good morning, ladies and gentlemen. It would be my privilege to serve as the session chairman this morning. To allow the maximum time for our speakers, I'll turn the microphone over to Bernie Bernstrom who will introduce our first speaker. MR. BERNSTROM: Thank you. As Vernal mentioned, Dan Jackson will be our first speaker. He is the Western Editor of Coal Age Magazine. Dan really doesn't need an introduction to this group. He's belonged to the Rocky Mountain Coal Mining Institute about 25 years. Dan is a native of West Virginia and he's an ex-coal miner. He graduated form West Virginia University as an electrical engineer and worked for Amherst and West Bending Coal prior to employment by Coal Age Magazine. Back in 1972 Coal Age moved him to Denver from New York City. MR. JACKSON: When Vernal Mortensen asked me speak to the members of the Rocky Mountain Coal Mining Institute earlier this year I found it impossible to say no to the guy because of what he has contributed to western coal. Little did 1 know that the subject he had in mind would be entitled, "An Outsider's View of Western Coal." At first I asked myself-I've been associated with the coal industry for some 38 years, 12 years in national operations and 26 years reporting on it. You might say that I've been married to two industries, coal and the business press for 26 years, but today I'll put on my business press hat and try to make an impression of what an outsider might think of western coal. But at the outset, let's get one thing straight: When you say press, whether it's business press, the media or whatever, and you heard some comments yesterday as far as what the media has done .to this industry and there's been some definitions bandied around as to just what an editor is. One of the most recent ones has defined an editor as a person who can talk on any subject with an open mouth. Now that's not my case. Secondly, I don't give long talks. Several years ago I was giving a rather lengthy talk to a group similar to this and it was halfway through the talk when I noticed one guy on my right looking at his watch quite frequently. I didn't mind that too much because all of us do that once in a while, but when he looked at his watch, took it off and shook it, I thought, "My God, better cut short." But for more than a decade western coal has enjoyed substantial annual increases in production from some 30,000,000 tons in 1970 to some 264,000,000 tons in 1981, but 1982 was a different story. We lost about 6,000,000 tons of production in that year. In 1983 it's expected to be a little worse than '82. Coal historically doesn't rebound from a recession as quickly as other industries. It takes about eight to 10 months longer for us to really get moving again and I'm afraid that you'll still have to don your fighting helmets and flack jackets when you go out into the market to sell your product. Western coal, as you know, has problems and al l of them are not going away when the recession ends and they won't go away overnight. I'm sure most of you are aware of what those problems are. Carl Bagge and Jim Harris, along with other speakers, at this meeting have educated us well on those problems and I'm sure you'll hear more from Jim Watt at today's luncheon. If everyone in this room were asked to list three orfourof the most serious problems facing western coal, I'd make book that the total of the answers wouldn't vary by more than 3 to 5%, if that much. But coal is not the only mining segment in the U.S. with problems. Metal and non-metal mining has its share, too. I'd like to step back into the past for a few minutes, if I may, to a time when our problems were just beginning. Since 1979 a third of the nation's mines, including coal, metal and nonmetal have been shut down. The total volume of all mining in the U.S. in that year totaled some $24 billion. Today that figure has dropped some 21 %. The after tax rate on return for mining companies has fallen from 6'/% in 1980 to minus 3% in 1983. But that's really not where our problems began. They began 20 years ago when a profound change began taking place in the U.S. economy. Our economy had been growing at about 2'/-3% annually without exception except for the great depression. Our inflation rate was about I'/%, interest rates were running about 6%, and the federal budget was $77 billion, really great figures compared to today. From 1960 to 1980 the federal budget increased almost 1.000% and taxed paid by individual families increased by 700% during that same period. Despite the huge increases in taxes, the federal deficit kept getting larger and larger year after year and within this 20 year period the national debt climbed to a trillion dollars. Economic progress of this type can't continue indefinitely without some serious consequences. The result of that economy, well, you know what happened and there is a direct relationship of that

Jan 1, 1983

By A. C. Wadhawan

In the present context of rapid industrialization, production of Lead-Zinc metals from low grade materials, residues and wastes can make substantial contribution to the supply of these metals in India. Recovery from secondary sources also plays an important role in conservation of mineral resources and lower power consumption. Conscious effort is therefore, required to increase the secondary metals which, besides saving in energy cost will also help in waste material management and keeping environment clean. The major thrust is, therefore, needed in this direction. During all these years, the Indian Lead- Zinc industry has made sustained efforts for recovery of metals from low grade ores and from metallurgical wastes and residues. The paper identifies the treatment of low grade ores by various technologies and techniques and the treatment of metallurgical residues and wastes generated during primary Lead and Zinc smelting in India. Some of the major achievements in past decade have also been elaborated in the paper. The strategies to be followed for continuing treatment of low grade ores and waste materials by adopting newer, environmental friendly technologies, in consonance with the rigid standards being adopted by most of the countries including India. have also been dealt with in the paper.

Jan 1, 1994

By Kirk A. Mcintosh

Augered, cast-in-place (ACIP) piles have been utilized in the United States for a wide range of projects since the 1950's. Due to the cast-in-place nature of the installation method (and lack of a driving criteria); however, ACIP piles have not been readily accepted by some practicing geotechnical and structural engineers. Since ACIP piles were initially developed, the installation equipment and techniques have been improved and refined and the number of experienced contractors has significantly increased. Over the past 10 to 15 years, the pile type has experienced significant growth in the United States (particularly in Florida) because engineers have become more knowledgeable and comfortable with its use. The Miami area, in particular, has experienced considerable growth in the utilization of ACIP piles primarily due to their usage on the $1 billion Miami Metrorail System project in the early 1980s. The economic advantages over other deep foundation types, coupled with some unique installation advantages, have shown that ACIP piles can be a viable foundation alternative on many projects. Even though ACIP piles have gained respect in the private sector, the pile type has generally not been readily accepted by government transportation agencies. The reluctance to readily accept this foundation type stems primarily from the quality assurance aspect of cast-in-place pile construction. Additionally, there has not been much research activity on this foundation type, technical papers, formal associations (other than the DFI), or a concerted effort to standardize the industry. This paper serves to discuss the state of practice for ACIP pile installation in the state of Florida.

Jan 1, 1997

By Victoria Vaccarezza, Corby Anderson

The demand for rare earth elements for everyday technology and applications has initiated much research into the extraction and recovery of these rare earth elements. An otherwise unknown group of minerals, eudialyte is a zircon silicate consisting of rare earth oxides (REO), contained in a unique mineral structure and represented by a complex chemical formula. Research into extraction and recovery of rare earth elements involves various beneficiation and hydrometallurgical techniques. The goal of beneficiation being to efficiently liberate and upgrade the REO content, followed by hydrometallurgy to extract the desired elements. This overview will discuss previous research on treating eudialyte group minerals via different mineral processing and extraction techniques.

By John M. Karhnak

The Bureau of Mines has a long history of research in Ground Control. For many years, this work was done at Bureau facilities by Bureau researchers. As the tiles changed, however, the area of research interest broadened, and additional methods of implementation, such as con- tracts, were added. 'Ibis paper outlines the organization, goals, and methods of implementation of the Bureau Ground Control Program, along with procedures for project selection. This program organization is followed by several specific examples of Bureau research that will be soon ready for use in the mines.

Jan 1, 1981

By G. K. Lee, Whaley. H., F. D. Friedrich, I. C. G. Ogle

"IntroductionCurrent coal combustion activities at the Canadian Combustion Research Laboratory (CCRL) reflect the increasingly important contribution that coal is expected to make in meeting our future energy requirements and in reducing our dependence on foreign oil. Widespread use of coal will, however, be heavily dependent on the ability of conventional and emerging combustion systems to cope with the disruptive conflicts caused by variations in fuel quality, on requirements for better equipment availability .and on the implementation of progressively more stringent environmental constraints.To minimize these conflicts, Energy, Mines and Resources Canada has embarked on a systematic sequence of research, development and demonstration- scale (R, D and D) initiatives to stimulate the utilization and competitiveness of thermal coal in both domestic and export markets through a number of complementary in-house projects and external contracts, considered to have short- to intermediate-term benefits to industry and society.Many of the in-house projects are funded in part by industry, whereas the external contracts are either fully funded (100070 government funding) or jointly funded (50% government - 50% project proposer).External contracts and shared-cost projects are an important adjunct to the CCRL in-house effort on coal combustion, because research data can be more effectively transferred to industry and because the commercialization of novel combustion systems can be accelerated significantly."

Jan 1, 1980

By Luke Clarkson, David Williams

The intent of this paper is to provide overview context to allow broader understanding of conventional tailings dam failure mechanisms. The research leverages global knowledge, experience, and data collection and interpretation for the safe and controlled management of the geotechnical stability of a tailings storage facility. The motivation for this review is to facilitate transparent access to tailings dam background and understanding. This paper addresses the core understanding of geotechnical failure mechanisms, and how these eventuate to instability and failure of tailings dam structures. This research focuses on foundation failure, internal erosion and piping, overtopping, seepage, seismicity, and slope instability and provides insight into what factors contribute to failure, how failure progresses due to such failure, anticipating and monitoring for the aforementioned failure modes, and designing to mitigate their risk.

Feb 15, 2021

By Phillip J. Mackey, Rodney T. Jones

"Copper and copper alloys remain key materials for society today, with important uses found in the electrical, transportation, and construction industries. Copper demand is rising, with projections indicating that by 2025 global refined copper demand will increase to 29.5 million tons, up from the 22.4 million tons anticipated for 2015. This will require the opening up of dozens of new mines and numerous new smelters over this time period. Fortunately, Africa has significant reserves of copper, and African copper can once again play a key role in contributing to meeting the rising global demand for copper. This paper provides a brief overview of the current copper smelting operations in Southern Africa. INTRODUCTION Copper and copper alloys are essential materials for today’s modern world. The familiar green copper patina colour seen on buildings and other structures sometimes belies its true “green” characteristic – copper is essential for key emerging technologies such as wind turbines, tidal generating systems, solar energy systems, electric cars and the like. Consequently, it is believed that there will be continued growth in copper demand in the years ahead. Projections indicate that by 2025, as an example, global refined copper demand will increase to 29.5 million metric tons, up from the 22.4 million ton level anticipated for 2015. This will require dozens of new mines, and of the order of the equivalent of 10 to 12 new 0.5 million tons of copper/year-sized copper smelters (after factoring projected copper produced by electrowinning (EW))—overall, a huge undertaking. Fortunately, Africa has significant reserves of copper, and African copper can once again play a key role in supplying this rising global demand for copper. Africa’s share of global mined copper production was about 10% in 2014; however this will increase significantly in future if announced new projects eventuate. Southern Africa has an important role to play in this process. The present paper provides a brief overview of copper smelting in Southern Africa."

Jan 1, 2015

By Dara L. Hrytzak-Lieffers

Canada has long since been a place that has led the world in mining development, in a safe, clean, and sustainable manner. This has led to the integration of corporate social responsibility (CSR) philosophy in corporate governance, policy, and programming. The paper will identify the basis of CSR practise in Canada?s mining industry and provide a Canadian example of CSR implementation. Biography Dara Hrytzak-Lieffers is the manager, corporate social responsibility at Cameco Corporation. She oversees corporate CSR initiatives including the Sustainable Development report and public engagement programs. Dara received her BA in International Studies from the University of Saskatchewan and an MA in International Conflict Analysis from the Brussels School of International Studies. She is a recent graduate of the World Nuclear University summer institute.

May 1, 2011

By V. I. Zhuchkov, L. A. Smirnov, E. I. Arzamastsev, A. A. Babenko

A brief analysis is given for state-of-the-art of manganese and chromium ferroalloy production in Russia and their consumption by metallurgy plants. The main causes of low output of manganese and chromium ferroalloys, and ways to resolve the issue of ferroalloy production development are considered.

Jan 1, 2004

By M Gwynne

McArthur River Mine is located approximately 50 km south-east of the NT township of Borroloola and approximately 120 km from the Gulf of Carpentaria. The mine hosts a series of layered shallow dipping tabular orebodies, with current reserves of approximately 22 Mt, grading 13.6 per cent zinc, 6.3 per cent lead and 65 g/t silver. Owing to economic considerations, the lower most orebody (No 2 orebody) has been selected for initial mine production. Following the completion of the No 2 orebody, mining will transfer to the lower grade and metallurgically more complex No 4 orebody. The mine employs a total of 235 people throughout the underground and surface areas. The majority of the workforce work a fly-in/fly-out, seven-day- on/seven- day- off roster with 12-hour shifts. Presently, a further 18 contractors are involved in trial mining areas. An apparent dip room and pillar technique has been selected as the primary mining method. Officially opened in September 1995, the current production rate of 1.2 Mt per annum will eventually escalate to 1.5 Mt per annum. Though most production is achieved through the use of conventional loaders, trucks and jumbos, the recent development of methods utilising scrapers, hand held machines and modified jumbos has produced encouraging results in steeper dipping areas of the mine. Initial production has been hindered by several factors including extensive and largely unpredictable faulting, worse than expected ground conditions and difficulties with some mining equipment. Compounded by the relatively thin 3 m ore seam, initial mining resulted in high dilution and poor production. This paper describes the development of unique planning and production systems that were evolved in order to overcome these problems and achieve the targeted production rates and head grade.

Jan 1, 1998

By Ian Baker, Xavier Pierron

"Iron aluminides hold great promise for intermediate temperature applications (to ~ 600°C) because of their excellent oxidation and sulphidation resistance and good strength. However, they have poor low temperature ductility, a feature which is exacerbated by water-containing environments. This paper presents an overview of the effects of environment on the ductility of iron aluminides, including the effects of iron aluminum ratio; ternary alloying additions, particularly boron; strain rate; and temperature. The mechanisms involved in water-induced embrittlement are discussed.IntroductionOver the last few years, it has became increasingly evident that the ductility and fracture toughness of many intermetallic compounds, particularly aluminides, are reduced dramatically if they are mechanically tested in either air or in hydrogen-containing atmospheres (1-5). For FeAI and Fe3AI, it has been shown that water vapor, for example in air at room temperature, can form atomic hydrogen by reacting with the Al atoms (1, 2). As a result in iron aluminides, the environmental embrittlement process is quite similar to traditional hydrogen embrittlement. This can be easily demonstrated by either testing an iron aluminide in an environment free of the deleterious species or by testing at high strain rates, both of which result in greater ductility. The purpose of this paper is to review recent progress in understanding environmental embrittlement in FeAI and Fe3AI, and to consider possible environmental embrittlement mechanisms. Greater understanding of this phenomenon will lead ultimately to remedies to this problem which is a major reason for preventing the practical application of these materials. First, some background on the iron-rich aluminides."

Jan 1, 1996