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By I. A. Minaev

The conditions of a stability of metallurgical films on a surface of solid on the basis of classical regularities of a thermodynamics are considered. For specific conditions of metallurgical processes the basic equations relevant to non-metallic inclusions (product of steel killing) migration and transfer through the interface boundary of metal-slag are obtained. The basic criteria equations of conditions of stability of metallurgical dispersed systems are developed in view of films formation. The probable thermodynamics reason of wetting due to formation of stable films are discussed. The experimental measurement of thin and thick films elastic resistance for metallurgical systems are carried out and the results are discussed. The presence of a wetting thick film increases stability of dispersed systems (facilitates an inverse implication of non-metallic inclusion in a melt) due to a barrier effect of wetting films. The quantitative evaluations of non-metal inclusion stability for steel in contact with any metallurgical slag are carried out. The results are in accordance with technological experience. Keywords: Inclusion removal, Film thermodynamic, Slag-metal dispers system

Jan 1, 2004

By Herbert E. Allen, Andrew F. Kingery, Spyros P. Pavlou

This paper examines and compares the role that chemical speciation plays in the environmental aquatic toxicity of two metals - copper and arsenic. Copper is shown to have well-understood chemical speciation equilibria, but poorly known species toxicities. Arsenic presents the opposite case, with unpredictable speciation in aquatic systems, but is relatively easy to evaluate toxicologically. Speciation is not currently incorporated into Water Quality Standards. This can have a major impact on the cost of environmental containment and cleanup.

Jan 1, 1992

By T Nassis, H M. Nel, T du Toit

Assmang Khumani Iron Ore Mine is exploiting the iron ore deposits that can be found in the Bruce-King-Mokaning farm areas in the Northern Cape, South Africa. The Bruce, King and Mokaning (Khumani) deposits are approximately 10 km south of the town Kathu, adjacent to the Sishen Mine. Assmang Limited is jointly owned and controlled by African Rainbow Minerals Limited and Assore Limited.Measurement, calculation and trending of plant throughput and chemical ore properties are critical in maintaining a successful beneficiation operation due to these values forming the basis of decision-making and thus promotion of efficient ore extraction. The Khumani management and engineering information system (MEIS) supplies information on key process parameters to an operational team and is required to do so within an optimal time frame, for maximum impact.Diverse data is put into the MEIS from multiple specialist systems, with interfaces that require manual intervention. Manual intervention is resource and time intensive to the point which limits the effect on the process and decreases the potential for value addition.Automation of interfaces decreases resource and time requirements, standardising plant wide data sources and providing the opportunity to provide specialist system data to decision-makers in a timely fashion, resulting in maximum impact on the process output.Engineering and metallurgical management systems were interfaced at Khumani Iron Mine by means of an automated table which facilitates the transfer of production data validated within the engineering system as input to the metal accounting system. This interface effectively assigns a master to each specialist data set employed for decision-making and delivers accurate process parameters to the production team within an optimal time frame, resulting in increased potential to improve beneficiation efficiency.CITATION:Nel, H M, Nassis, T and du Toit, T, 2013. The role of metallurgical and engineering information systems in the optimisation of iron ore beneficiation processes, in Proceedings Iron Ore 2013 , pp 453-458 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By M. Dworzanowski

Beneficiation, in the context of this paper, has two distinct definitions. From an economic perspective, beneficiation relates to adding value to a mined raw material. From a metallurgy perspective, beneficiation relates to processes used to upgrade the mined raw material. Clearly then, ?economic beneficiation? is dependent on ?metallurgical beneficiation?. South Africa possesses the world?s largest mineral resources by value and is a significant global producer of many mined commodities. Significant metallurgical beneficiation of ores does occur in South Africa. The role of metallurgy in economic beneficiation will be examined in terms of current practice and the potential for expansion. South Africa?s main mining commodities will be covered ? namely gold, platinum, coal, iron ore, manganese, chromium, vanadium, copper, nickel, titanium, zirconium, uranium, and diamonds.

Sep 1, 2013

By W J. Rankin

Metals are well suited to sustainable development goals. They are not biodegradable and have virtually an unlimited lifespan and the potential for unlimited recyclability. Thus metals can be considered as renewable materials. However mineral resources, the source of primary metals, are ænon-renewableÆ as their supply is finite, but this does not necessarily mean scarcity. In this paper the results from a series of Life Cycle Assessments of primary metal production processes for copper, nickel, lead, zinc, aluminium and steel have been used to examine how metals may contribute to societyÆs transition to sustainable development. Particular issues considered include:current metal reserves and how these may change in the future; some of the environmental impacts (Total Energy, Global Warming Potential and Acidification Potential) associated with primary metal production and how they will be exacerbated by declining ore grades; new processing technologies with lower energy consumptions and improved metal extraction efficiencies that will reduce reserve depletion and environmental impacts; increasing the utilisation of æmetals in useÆ by recycling, with particular reference to aluminium; and the potential impact of a carbon tax on metal prices and how this may influence the ways in which metals are used in the future.

Jan 1, 2002

By Phil Pennington, D. Jack Adams, G. Ward Wilson, Virginia T. McLemore, Luiza Aline F Gutierrez, Rodney Shields, Steven Lockwood, Samuel Tachie-Menson

Microorganisms are directly or indirectly involved in many chemical alterations and in the decomposition of minerals required for their growth. Microbial dissolution of sulfide minerals under acidic conditions can produce over 1,000 times more Acid Rock Drainage (ARD) than chemical action alone. Microbial actions can cause precipitation of minerals, adsorption or release of metals, and formation/destruction of organic-metallic complexes. Soluble minerals can serve as oxidizing substrates, electron donors/acceptors in redox reactions, and can be directly involved in cell metabolism. Microorganisms and microbial oxidation-reduction reactions and their contribution to mineral mobilization and stabilization will be discussed.

Jan 1, 2005

By R. A. Kleiv, H. Havskjold, N. Church, T. Malvik, M. Tro, E. Larsen

Liberation is one of the major purposes of comminution in mineral processing. In the simplest form, two or more minerals are present in a particle and have to be reduced such that the individual particles contain only one mineral. The complexity of the mineral intergrowth varies from ore to ore. Poor magnetic separation of iron ore may have many causes. In this paper, the emphasis is given to the problem of fine magnetite inclusions in quartz or other gangue minerals. This is highlighted by two Norwegian cases: one on a magnetite ore and the other on a hematite/magnetite ore. The inclusions in question are so small that they are not liberated by reasonable grinding. In both cases, the result has been either poor recovery or lower grade concentrates than desired. The first example concerns production of direct reduction concentrates from magnetite. Magnetic inclusions in gangue particles will be magnetized enough for the particles to pass into the concentrate. The second example is given a more detailed study, where the problem is caused by silicates with small inclusions of magnetite in a combined LIMS and WHIMS separation. This study included microscopy, Davies tube testing, and magnetization measurements. In particular, large gangue particles with magnetite inclusions were shown to have a tendency to bypass the LIMS separators as drag forces in presence of hematite are large. Such particles will then be picked up by the WHIMS as their magnetization is higher than for hematite. This was demonstrated by Davies tube tests, which indicated that such particles were picked up in preference to hematite particles. However, the Davies results did not give a good quantification. Magnetization measurements of gangue particles with magnetite inclusions was shown to be a better tool to quantify the magnitude of the effect of magnetite inclusions in magnetic separation.

Jan 1, 2018

The Role of Mineral Processing in the Development of Cement with Low Carbon Emissions

Sep 13, 2010

By P. M. Swash

The paper describes the use of mineralogical methods in the exploration and evaluation of primary diamond occurrences. The most common methods that are used include the systematic search for kimberlitic indicator minerals, surface textural study of the indicator minerals, (garnet, spinel, ilmenite and chrome diopside) and alluvial macrodiamond studies so as to understand their provenance and guide exploration towards diamondiferous targets. The mineral chemistry of the indicator is used to positively assess the origin of the mineral grains and is also pivotal in the determination of the diamond potential of a deposit. Petrography of the primary deposit is able to identify the body to be kimberlitic and is also a support to the mineral chemistry findings. Unambiguous proof of a prospects potential to contain macrodiamond is proven by the occurrence of microdiamonds in the residues from the rock. The presence of a sufficient number of microdiamonds in the rock is enough to determine a semiquantitative grade estimate and warrant further metallurgical evaluation so as to determine its actual macrodiamond content.

Jan 1, 1991

By John D. Morgan

The United States is the world's most productive nation and its citizens enjoy one of the highest material standards of living of any people in the world. Materials and energy are the lifeblood of any industrialized economy. Annually the United States uses over 4 billion tons of mineral materials and fuels, or 40,000 pounds per person as detailed in Figure 1. Domestic processed materials of mineral origin and energy are valued at more than $150 billion annually, and they are derived largely from domestic sources, supplemented by imports, as detailed in Figure 2. In recent years the superior productivity of the United States has also enabled it to give food and manufactured articles to many other less fortunate nations and peoples of the earth. What then is our concern with materials at this time? Seeing the burgeoning increases in our mineral demand: from 2 billion tons in 1950, to over 4 billion tons today, and projected to 11 billion tons by 2000 - we are getting questions concerning our ability to continue to increase production sufficiently for the future.

Jan 1, 1974

By The Honourable George Prudham

"I AM PLEASED indeed to be present with you here today and to be taking part in the proceedings of your convention. You have been greeted and welcomed to the Province by Premier Manning who is also provincial Minister of Mines and Minerals, and to this City by Mayor Hawrelak. As Minister of Mines and Technical Surveys in the federal government and as Member of Parliament for Edmonton West, I have been asked to share the honour of extending greetings and a cordial welcome to all.It is a happy coincidence that this representative national gathering, indicative of the growing strength and significance of a great basic Canadian industry, is taking place in the Macdonald Hotel, the new addition of which marks another important step forward in the progress of this City and district.This happens to be the third national convention of the C.I.M. that I •have had the pleasure of attending and I trust that I am not presumptuous in expressing the hope that I will have the opportunity of attending many more conventions of the Institute in my present capacity.Dr. Kidd has bestowed on me a high honour by asking me to be Co-Chairman of this Inaugural Session of the Convention and thus to share with him the responsibility of presiding over the proceedings of this afternoon."

Jan 1, 1953

By A. R. Farkoosh

Al-Si based alloys have been recently used by automotive industry for highly stressed engine applications. Due to severe working conditions of the engine parts, existing alloys hardly endure high pressures at high temperatures. This necessitates alloy modifications to enhance the elevated temperature performance. In this study, the effects of trace nickel additions on the microstructural and mechanical properties of A356+0.5Cu alloy have been investigated at different aging conditions. Electron probe microanalysis (EPMA), scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to study the microstructural changes. Aging curves have been obtained by hardness measurement. It was seen that the presence of additional nickel introduced many complex intermetallic phases within the microstructure which led to improved high temperature mechanical and aging response.

Jan 1, 2011

By J. Y. Oldshue

INTRODUCTION The field of fluid mixing involves many different kinds of process objectives. In order to classify these objectives, Table 1 gives a listing of five basic application categories, gas-liquid, liquid-solid, liquid-liquid, miscible liquids, and fluid motion. However, each of these areas can be broken up into two different concepts one involved with uniformity of solids or liquids as a criteria, and the other involved with chemical reactions or mass transfer. The things that we would do to design a fluid mixing for solid suspension are quite different from things that we would do to design a mixer for heat transfer or gas-liquid mass transfer. Therefore, there are really ten separate mixing technologies. Each of these areas has its [ ] own principles of fluid mechanics, scale-up techniques and application experience. We will take a look at each of these areas and look at some of the ways that we can handle fluid mixing applications which.

Jan 1, 1979

By D. W. Fuerstenau

Understanding how cationic surfactants affect the interfacial behavior of quartz is important in mineral processing and environmental engineering. This paper presents the results of a study of the effect of the molecular structure of cationic surfactants on the interfacial behavior of finely ground natural quartz. Most of the experimental work involved the determination of zeta potentials and the stability of quartz suspensions. Some measurements of induction times and the flotation response of coarser particles are also included. How these surfactants affect interfacial behavior is discussed in terms of adsorption mechanisms. The molecular structure (number of hydrocarbon chains, type of ionic head group, number of ionic head groups on the molecule) of these reagents was found to significantly affect their surface activity.

Jan 1, 2014

By D Bradshaw

The recovery of molybdenum at Kennecott Utah Copper (KUC) has become increasingly important as its demand and price have risen dramatically in the last few years. Consequently, the flotation behaviour of the molybdenum bearing mineral, molybdenite, has received a significant amount of attention. The flotation performance of molybdenite generally lags that of the copper sulfide minerals and is much more variable. There are many factors including particle size, liberation, surface slimes and oxidation that contribute to this and also much speculation as to the relative contribution of each of these factors. This paper discusses the morphology of the molybdenite found at KUC, the mineral associations in the different lithogical ores types and the effect that each of these has on flotation performance. Quantitative mineralogical analysis and an assessment of particle shapes are used to explain that flotation behaviour does not necessarily follow expected trends and that some behaviour is counter-intuitive. This unique behaviour can be explained by the morphology and anisotropic nature of molybdenite.

Jan 1, 2008

By Dennis W. Leonard

Let us begin our discussion by looking at historical and current levels of sales of both natural and synthetic zeolites on a world-wide basis. Due to the understandable reluctance of some companies to disclose sales data, some estimation has been necessary regarding the tonnages and values shown in Table 1. We are confident, however, that they are within acceptable limits, especially the numbers referring to natural zeolite.

Jan 1, 1979

By J. P. Schde

The authors deal with nickel production and usage patterns, nickel's first-use and end-use, examples of nickel applications in modern technology, e.g., energy generation and conservation, environmental protection, the oil and gas industry, construction and machinery, food production, conservation and distribution, consumer durables and the like. A special section of the paper is devoted to new applications of nickel in the electronic industry, modern corrosion control and the building and construction industries. The need to defend traditional markets for nickel while striving to find new applications, is also stressed.

Jan 1, 1988

By Michael A. Redfearn

The use of nitrogen in molybdenite flotation circuits is a relatively new concept utilized by only a few mines around the world. This paper briefly discusses circuit chemistry and the reason for its success. It follows the entire testing process which resulted in a sodium hydro-sulphide dosage reduction from 18.5 to 4.4 lbs/ ton (9250 to 2200 g/t) through to the final installation of an inert gas generator which will produce reagent savings in excess of one million dollars annually. A description of the various types of nitrogen generators commercially available is included.

Jan 1, 1983

By W. J. Bennett

WHEN Dr. Horace Fraser, your President, invited me to speak to you today I advised him in confidence that I was leaving my present positions on April 30th. In the circumstances it seemed to me that this audience might prefer to have as its speaker one who wo.uld J1ave a continuing association with the atomic energy programme. Dr. Fraser was kind enough to suggest that my re-marks might he of special interest to you, since I would be able to sum up my views on the atomic energy programme. I hope that I will not disappoint him or you on that score. I am particularly pleased that my last public appearance in my present positions should be at the Annual Convention of the C.I.M. since, as all of you know, a very important part of my work has been in the mining field. As it happens, my first public address on the subject of atomic energy and its raw material -uranium -was made at your Annual Convention in Montreal in April, 1949. It seems fitting that my final address should also be made at this convention -nine years later.

Jan 1, 1958

By A. Korchevisky

Environmental self-monitoring is one of the advanced approaches for industrial sustainability programs. Organization for Economy Cooperation and Development (OECD) defines self-monitoring as ?the system of organizational and technical measures put in place and financed by [the] regulated subject? in order to ensure their compliance with regulatory requirements?1. Self-monitoring is beneficial for industrial operators, communities, and governments. Industrial companies use self-monitoring as a central element of their compliance management that allows them to fulfill their duties, obligations, and to avoid citations. When industries control their emissions and ensure workers are not exposed above the regulated limits, communities are better. It is impossible for an EPA, OSHA, or MSHA inspectors to be close to every emission source or workplace full-time. It is much more effective for industries to self-monitor, under due supervision. Occupational conditions are a very important part of industry and health and safety self-monitoring should be highly prioritized. In this paper we will research the regulatory basis and best practice of occupational self-monitoring. We will show that not only is self-monitoring a vital element of an occupational health & safety management system, but that you need a management system for affective monitoring.

Jan 1, 2012