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By Patrick R. Atkins

Energy issues will have increasing impacts on decision making in all facets of society over the next few decades. Industrial users of energy and producers of products that affect energy use must be fully aware of the implications of their processes and products on the energy situation. This paper describes a model that has been developed for the aluminum industry that allows scenarios to be evaluated to gain improved understanding of possible implications for our businesses. A brief overview of the model is provided.

Jan 1, 2006

By Patrick R. Atkins

Energy issues will have increasing impacts on decision making in all facets of society over the next few decades. Industrial users of energy and producers of products that affect energy use must be fully aware of the implications of their processes and products on the energy situation. This paper describes a model that has been developed for the aluminum industry that allows scenarios to be evaluated to gain improved understanding of possible implications for our businesses. A brief overview of the model is provided.

Jan 1, 2006

By Mark F. Vancas

Virtually every new process plant project goes through the ?Feasibility Study? phase before actually being built. The Feasibility Study is used by the owners and the bankers to evaluate the economics of the project and determine whether or not the proposed investment meets their respective investment guidelines. With a positive result, the project is approved and goes to construction and operation. Then, the actual costs are incurred and these actual costs may or may not agree with what the Feasibility Study predicted. Just how good have Feasibility Studies been? This paper looks at various projects and compares predicted to actual results and also gives information on how to spot a poor feasibility study.

Jan 1, 2003

By Jong-Shin Chang

The Onsan smelter has tried to do various activities to decrease operation costs. With several expansion projects, the Onsan smelter has aimed at not only a quantitative growth but also qualitative growth through efforts improving operations equipment and processes. Activities to reduce operation costs have been one of those efforts. In particular, the energy cost of operation has been a main target for reduction. The activities to save energy have been carried out in two ways. One is to recover and utilize waste heat as much as possible and another is to replace existing equipment and processes with more energy-efficient ones. This paper reviews recent improvements and future plans for energy saving activities at the Onsan smelter.

Jan 1, 2006

By R. J. Wesely

Non-ferrous smelters traditionally have a hot gas handling system. In these systems, the dust is captured as a dry material which is often recycled to the process. Some smelters use wet gas cleaning methods with the recovery of the dust as a wet sludge. Although this sludge can be recycled to the process, in some cases it is preferable to dispose of the sludge. This paper will discuss the disposal methods available and specifically will deal with one type of sludge which has a high arsenic and high lead content. Problems with this sludge were investigated and methods were tested with the aim of stabilizing the sludge so that it passes the EPA TCLP test. Results of the laboratory tests are given.

Jan 1, 2000

By W. H. Jay

Sulphide-containing minerals, particularly iron, lead to acid formation. In turn, the acid generates effluents such as copper acid drainage (AMD). The Berkeley Pit in Butte, Montana, USA and Mt Lyell in Tasmania, Australia, represent just two of many sites throughout the world for which acceptable treatment methods are required. In the gold cyanidation process, the presence of copper creates both a significant cost impediment and a potential environmental hazard. The tailings dam failure at Baia Mare in Romania which led to the release of copper and zinc cyanides created a major environmental disaster. The application of non-toxic water soluble polymers and ion exchange resins to selectively recover copper from AMD solutions, and the in-plant treatment of copper cyanide solutions and slurries to recover copper and recycle cyanide to prevent cyanide entering the tailings impoundment will be discussed. The economics of the various processes will be highlighted.

Jan 1, 2003

By Huang Rui

The coal asphalt is combusted at different temperature in a heating cabinet with the temperature limit by 1200°C. By comparing the mass of the remainder of each experiment, the completely combusting temperature of asphalt smoke can be determined. Based on the experimental process of asphalt smoke, a discrete mathematical model of the asphalt smoke combustion is set by theoretic analysis. Through computer programming, the dynamic combustion process of asphalt smoke is calculated to simulate the experimental model. The result of experiment shows that coal asphalt can mostly react upon 500°C and the mass of remainder is 49.41% to initial mass of sample in the condition. The computing result shows that the temperature and the concentration of asphalt smoke influence its burning temperature approximating linearity. The consumed quantity of fuel to ignite the asphalt smoke needs be considered with the two factors.

Jan 1, 2006

By R. M. Luna-Sánchez

Electrochemical studies, particularly Evans? diagrams, have been employed in hydrometallurgy to simulate and explain the redox phenomena that take place at mineral and metal surfaces during operations such as leaching and cementation. However, despite their utility, in some cases, the combination of the cathodic and anodic branches, determined separately, does not reproduce the chemical environment present when both processes occur simultaneously on a specific surface. In the present paper, limitations of Evans? diagrams are analyzed through two examples: silver sulfide cyanidation and gold cementation on zinc. In both cases, the surface kinetics are sensitive to the local pH and cyanide levels. When the electrochemical oxidation of silver sulfide or the reduction of gold are performed in the absence of its corresponding redox reaction, the local pH obtained does not simulate the real situation and the combined reaction kinetics may be very different from those determined from the Evans? diagrams.

Jan 1, 2003

By R. D. Prengaman

Lead usage in paint, anti-knock gasoline additives, pipes, seals, and solder has declined markedly over the past 30 years. Products utilizing the unique properties of lead and its ability to be recycled have survived and grown. These products include shielding, glass (particularly TV and computer screens), sheet for roofing, stabilizers for PVC, insoluble anodes for metal production, electronic solders and lead acid batteries. With the loss of markets many companies have decreased lead product development efforts. Much of the patent lead materials development is devoted to lead acid batteries. In the past 25 years, the automobile battery has been almost doubled in power and reduced in weight, leading to a nearly three-fold increase in performance. Corrosion-resistant lead alloys and improved battery designs have made battery lead usage more efficient. The same corrosion-resistant battery alloys are utilized to increase the life of electrowinning anodes. The challenge for lead product development is not only to maintain and improve the existing lead products, but also to develop the growing lead acid battery market for telecommunications, uninterruptive power sources, remote area power, hybrid and electric vehicles. Lead

Jan 1, 2000

By A. V. Tarasov

The high efficiency of autoclave processes is attributed to the fact that they are suitable for processing of refractory raw materials, have low capital costs and high productivity, ensure integrated utilization of the feed materials, produce innovative saleable products, completely eliminate any air emissions, provide low-waste or waste-less technology, as well as mechanization and automation of production processes. In the immediate future, it might be expected that autoclave processes will find use on commercial scale for production of heavy non-ferrous metals in combination with other processes (hydrometallurgical, upgrading, sorption and solvent extraction, electrolytic, etc.) to ensure: -Integrated processing of refractory ores and concentrates (pyrrhotite, zinc, copper-zinc, lead-zinc, nickel-cobalt, copper, pyrite); -Production of metallic powders of base metals as commercial products (copper, cobalt, nickel, etc.), composites on their bases, final products and saleable salts. Processing technologies incorporating autoclave processes, especially, at the stage of liberation (chemical upgrading) of minerals, are characterized generally by high overall recoveries of valuable constituents significantly exceeding recoveries common for conventional pyrometallurgical processes (for some elements by several tens of percent). An example is processing of low-grade refractory pyrrhotite concentrates using autoclave liberation of feed material under pressure of a new reagent, i.e., sulfur dioxide. The use of sulfur dioxide ensures a significant improvement in the recoveries of non-ferrous metals and platinoids to sulfide concentrate and smelting of the latter increases the capacity of the smelting units employed and minimizes the yield of discard slag and loss of metals in slag; in addition, it resolves the problem of sulfur dioxide utilization.

Jan 1, 2003

By J. P. Rodier

Despite the good years that the non-ferrous business is now enjoying, one should not forget that in this business growth rates are low, fixed assets are high and prices are more cyclical than in other businesses. Increasing environmental concern puts the industry under pressure. Lead and zinc companies are now profitable and profitability in the next ten years will depend on size of units, location, and choice between new technology and upgrading current ones. Implementation of Metaleurope was a strategic move. It produced a company of sufficient size to achieve new steps in cost cutting and yet remain flexible enough to deal with rising variety of primary and secondary raw materials.

Jan 1, 1990

By C. A. Landolt

Inco pioneered the use of tonnage oxygen in non ferrous metallurgy when it commissioned the first industrial oxygen f1ash smelting process for the treatment of copper concentrates in the ear 1y fifties. This techno logica1 innovation was followed by other applications of technical oxygen. Inco is currently implementjng a Sulfur Dioxide Abatement Program designed to reduce SO2 emissions from the smelter by 60% in 1994. The new flowsheet includes new equipment for the oxygen flash smelting of Cu-Ni concentrates and for flash conversion of chalcocite. Oxygen smelting and converting technology will lead to a substantial decrease in use of fossil fuels and to generation of high strength S02 off gases suitable for efficient fixation in a new acid plant.

Jan 1, 1992

By C. A. Landolt

Inco pioneered the use of tonnage oxygen in non ferrous metallurgy when it commissioned the first .industrial oxygen flash smelting process for the treatment of copper concentrates in the early fifties. This technological innovation was followed by other applications of technical oxygen. Inco is currently implementing a Sulfur Dioxide Abatement Program designed to reduce S02 emissions from the smelter by 60% in 1994. The new flowsheet includes new equipment for the oxygen flash smelting of Cu-Ni concentrates and for flash conversion of chalcocite. Oxygen smelting and converting technology will lead to a substantial decrease in use of fossil fuels and to generation of high strength S02 off gases suitable for efficient fixation in a new acid plant.

Jan 1, 1992

By Harvey Alter

National attention in, recycling focuses on municipal solid waste (MSW), even though only about 50'million tons or so of MSW can be recycled, including grass, leaves and other yard wastes. The scope and value of the recycling of industrial "wastes" is much greater. It is possible to account for some 240 million tons of material recycled at the industrial scale annually, which is likely a conservative estimate. Some of this recycling reduces what would otherwise be hazardous waste to 'comrnodities and non-hazardous residue. Global trade in recycled commodities is outlined, as well as the-effect of the Basel Convention on the Trans boundary Movement of Hazardous Wastes A recent Decision under the Convention can, diminish the trade; deny developing countries needed secondary raw materials, and put world markets in chaos. Current U.S. government policies and activities toward ratification of the Convention, and possible new regulation of industrial recycling activities, will be discussed. There are federal proposals that would regulate industrial recycling differently for on-site and off-site facilities and judge legitimate or "sham" recycling according to the concentration of so-called "toxics along for the ride."

Jan 1, 1995

By Leonard A. Duval

This concept employs a viable energy saving method that uses a solvent to separate oil from particle matter; it can be used in metal forming industries to deoil sludges, oxides, and particle matter that is presently committed to landfill. If oily particles are used in their oily state, severe consequences to environmental control systems such as explosions or filter blinding, occur in the air handling equipment. This is due to the presence of hydrocarbons in the stack gases resulting from the oily particles. After deoiling, the particles can be recycled and the separated oil can be used as a fuel. The process does not produce a waste of it's own and does not harm air or water. It demonstrates the dual benefits of being commercially viable and in the national interest of conserving resources.

Jan 1, 1994

By A. N. Aposhian

The electronics industry generates tin/lead bearing by-products that can be recycled for their metal value. This paper will cover the processes used to recycle these tin/lead bearing byproducts from the plating, circuit-board fabrication and assembly industries. Though these processes are well known to the companies who do the recycling, few outside the industry including the generators of the by-products, understand the processes or needs of the industry. This paper will give a broad overview of these processes, and describe the services provided by this industry. The paper will also touch upon the future of the recycling industry, including the legislative and environmental push for the elimination of lead from electronics.

Jan 1, 2000

By Thomas Niehoff, Dave Stoffel

"Energy in the form of natural gas, oil and electricity is expensive and will continue to be a rare resource in the future. Recycling of metals, instead of primary production, is a logical and crucial step towards energy conservation. Energy consumption can be impacted by using advanced combustion systems for metals recycling. Air-fuel combustion has been the conventional method to melt and recycle metals. Global competitive pressures, “greenhouse” gas emissions, and high energy prices force melt shop operations to optimize energy usage and reduce overall operating costs. Oxy-fuel combustion and process technology can be applied to metal recycling operations to meet these objectives. Linde has converted several hundred furnaces from air-fuel to oxy-fuel technology and has extensive experience in optimizing the use of oxygen in furnaces. Additionally, Linde has the process knowledge necessary to avoid costly start-up issues that can accompany the transition to oxy-fuel technology. This paper will describe the benefits and potential issues for conversion to oxy-fuel.IntroductionThe furnace combustion system is the heart of a fossil fuel fired melting process and must be properly matched to the furnace to work as one cohesive unit. Furnaces vary widely in size, shape and features. Rotary furnaces are barrel-shaped and can be designed for tilting or nontilting operation. In a rotary furnace, the products of combustion create a single or double pass through the furnace prior to exiting. Reverberatory furnaces are box-shaped and can also be designed for tilting or non-tilting operation. Reverberatory furnaces are constructed of single or multiple chambers, with or without metal bath movement, and designed for continuous or batch processing. Different furnaces are used for different feedstock materials and products.Furnace combustion systems also vary in many ways. Combustion systems can be of air-fuel or oxy-fuel based technologies, or a combination of the two, resulting in an air-oxy-fuel system. Each of these types of systems has different combustion characteristics which can produce very different results. Here we will describe specific differences in melting processes and their associated energy requirements."

Jan 1, 2009

By G. C. Amstutz

The topic of the industrial applications of mineralogy is a vast field which can be adequately covered only in a large book or by a two or three semester course. This paper recalls experiences of the writer in this field, a task requested by the Process Mineralogy Committee. Therefore, this paper is largely an account of the industrial mineralogy problems I was involved with, since my student years, Although I will treat each application only briefly, it is hoped that they will illustrate to the students in the field how varied are the applications of mineralogical methods. In this respect, I want to emphasize that it is important for mineralogy teachers to point out the usefulness of mineralogical methods much more often in their courses. Not only does that help prepare young individuals for industrial careers, but also it arouses their feeling of consciousness of public responsibility which is an important attribute for the world's scientists. When professors utilize the varied applications in their teaching of mineralogical methods students then understand better the significance of learning those methods and appreciate the many years of necessary university preparation. The first time I was involved in an application of mineralogical methods was about 1944 as a student of Professor Paul Niggli. He was asked to study the problems of ice crystallization on wings of airplanes. The ice formed at high altitudes and during the winter. This was not outside his realm of expertise because he was the main initiator of the Snow Research Institute on the Weissfluhjoch in Switzerland. I believe that the work of this Institute was an important factor in stimulating much of the snow research subsequently carried out at the United States Army Snow Research Center, which was located at that time in Willmette near Chicago. Dr. Bader, one of Paul Niggli's former students, was the Director of Research at Wilmette at that time and for quite a number of years thereafter. A mineralogist-crystallographer can make important contributions to a better understanding of the problems of snow and ice formation, avalanche hazards, and the prevention of hail. The habits of snow crystals are essentially a function of the temperature and the humidity,

Jan 1, 1982