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By Andrey Tarasov, Erki Unn, Valery Paretsky

"The stability of the markets of energy resources and labor in countries of the Baltic Sea Region including Estonia is determined to a significant degree by the use of combustible shales as fuel and their distillation resulting in generation of up to 70% of non-recyclable waste. The objective of this business plan is to substantiate the investments for establishment of a new facility in Estonia for waste-less and environmentally safe processing of fossil minerals and man-made products generated in the shale industry, as well as other hazardous wastes. The proposed facility will use a basically new waste processing technology developed in Russia - i.e., processing in sparged molten slag This technology eliminates any release of harmful pollutants to the environment and a facility using this technology does not require, therefore, any sanitary protection zone.IntroductionIn the Baltic region, and first of all in Estonia and some other European territories, there are large natural deposits of combustible shale, which due to the lack of other own resources of energy and hydrocarbons for the chemical industry is burned and distilled with low technical and economic efficiency generating large amounts of toxic and highly toxic wastes and intermediate products. Currently, the penalties for disposal of such wastes have grown to such an extent that shale burning and distillation might become unprofitable. This might result in suspension of the given operations, which in turn will affect in an adverse way the markets of energy resources and labor market in those countries. Furthermore, in addition to the “shale problem”, Estonia, similarly to most member countries of the European Union, faces the challange of environmentally safe processing of highly toxic wastes, such as municipal solid wastes, oilpolluted materials, medical wastes and infected materials, spent rubber tires, etc. These wastes are at present stored or processed with release of a significant quantities of extremely toxic cancerogenic substances (dioxins, furans) or collected and exported for treatment at an extremely high cost and with a loss of valuable components contained in these types of waste and often with return of supper toxic processing products."

Jan 1, 2008

By Ashok D. Dalvi

Production of nickel from laterite ores has occurred for over 100 years beginning with processing of garnieritic ores from New Caledonia. However, until now the world nickel supply has been predominantly from sulfide sources. Going forward, the authors project that the production of nickel from sulfide ores will remain more or less constant. Most of the expansion in nickel production capacity over the next ten years will come from processing of laterite ores. Thus the capital and operating costs of new laterite projects will have significant impact on the nickel supply and therefore price. The authors have reviewed the history and capital and operating costs of various recent laterite projects and capital and operating costs of these projects and those "on the drawing board". The authors have also evaluated the risk associated with such projects. The paper will discuss the impact of this and the recent history on the future development of laterite nickel projects.

Jan 1, 2004

By T. Lezhava

Recycling technology of spent Mn-Zn system batteries has been worked out and tested in laboratory scale. The proposed technological scheme includes the following basic operations: breakage of batteries, hydro-vibrated treatment of broken up mass, electrolysis by using alkali electrolyte. This method enables extracting of 200-220 kg zinc in powder form, of 300-350 kg manganese concentrate and of 130 kg steel in the form of scrap per tone of broken up batteries.

Jan 1, 2006

By Hong Yong Sohn

On the occasion of this symposium in my name, I reflect upon the contributions of my academic mentors and early associates who helped shape my professional career. I was fortunate to have these people around me during my graduate work and at the start of my professional career. In forming my view of the technical field and career, they represented academia, research institutions, industry, and different parts of the world.

Jan 1, 2006

By David M. Beckwith

Increased globalization and outsource manufacturing complicate the procurement and enforcement of intellectual property rights on a worldwide basis. Recent legislative and case law developments in the United States highlight the importance of a multinational intellectual property strategy. IP lawyers David Beckwith and John Hankins will discuss planning and pitfalls in this rapidly changing trans-border environment. Topics to be discussed include harmonization with international patent laws, protecting your technology and market space with a comprehensive approach to IP, and patent enforcement issues relating to import/export of products and components in the United States.

Jan 1, 2006

By H. Kurama

In this paper, utilization of fly ash as a value added product in areas such as novel materials, waste management, fillers and agriculture is reviewed with the aim of helping the expand of the usage of fly ash and reduce the environmental and economic impacts of disposal. The used unburned carbon benefication/treatment methods such as low temperature combustion, froth flotation, partical size classification and electrostatic separations to remove unburned carbon particles from fly ash are also discussed.

Jan 1, 2006

By Kurt Westerlund

Cooling of hot sticky gases with solids in a circulating fluidized bed called FLUXFLOW is described. Fluxflow is used for gas streams from metallurgical reactors, e.g., Isasmelt copper in Australia and TBRC for lead in Sweden. The features and potential of this technology in metallurgy and waste treatment ie described. The FluxfLow la a new, cost efficient high availability solution to treat hot sticky gases that has made new gas handling and heat recovery flow sheets available to the process industry.

Jan 1, 1994

By Kang-In Rhee

Nonferrous metal recycling not only provides energy saving and environmental benefits but also is a significant factor in the supply of various types of metals used in our society. Recycling plays an important role in establishing the sustainability of materials. The total amount of recycled nonferrous metals by weight accounts for less than 5% but their value is larger than 50% compared to ferrous metal recycling which consists of about half of the total metal recycling in weight. This paper describes trends and typical achievements in nonferrous metal recycling and overviews the present and future of nonferrous metal recycling technology and business in Korea.

Jan 1, 2006

By John O. Marsden

The past fifteen years have seen a number of important developments in copper hydrometallurgy, including the commercial application of biological heap leaching of secondary (chalcocite-dominant) copper ores, the commercial demonstration of chalcopyrite concentrate leaching technology using pressure leaching and biological processes, and the application of novel configurations of solution extraction circuits. Significant emphasis is now being placed on the development of effective stockpile leaching practices for primary ores (chalcopyrite and bornite-dominant mineralization). Some of these developments have been highly successful, and will pave the way for further development and commercialization. Others have been less successful. These developments are reviewed in the context of the metal price cycle and trends for the future are identified.

Jan 1, 2006

By Corby Anderson

The efficient separation of palladium from the transition metals copper, nickel and iron can be effected by passing a leach solution of these metals through a column of the silica polyamine composite material, WP-1, patented by Purity Systems Inc (PSI), Assignee, University of Montana with exclusive license to PSI. The separation can be done at the intrinsic pH of a nitrogen species catalyzed (NSC) oxidative pressure leach solution (~0) and stripping of the palladium from the composite can be effected with hydrochloric acid/ammonium chloride solutions at 50oC. Batch capacities of the composite for palladium are ~ 1.8 mmol/g resin. The possibilities for isolating the metal from the strip are discussed. Given the proven longevity and rapid capture kinetics of the polyamine composites, this new approach should prove to be an economically viable alternative to the multi-step concentration processes practiced in the PGM industry to date.

Jan 1, 2003

By John Frederick Colloghon, O&apos

Bulong remains the only hydrometallurgical process plant in the world that recovers nickel and cobalt directly from high pressure acid leach (HPAL) laterite leach liquors without need for precipitation of an intermediate product (e.g. sulphide, hydroxide or carbonate). Direct solvent extraction (DSX) of both nickel and cobalt in combination with electrowinning of nickel has been operation at Bulong since early 1999. Focus in the first years has been on ramp-up and resolution of commissioning problems. More recently the focus has been on de-bottlenecking and process optimisation. A number of significant process problems have been resolved, the most difficult being the formation of gypsum in the nickel solvent extraction circuit. Sound control of process chemistry is essential to ensure the production of high quality nickel and cobalt products at the lowest possible cost. This paper describes the numerous changes and enhancements to the process chemistry and plant equipment at Bulong and discusses the importance of ore leach chemistry on downstream impurity metal removal. Potential additional enhancements to further reduce unit costs are also presented.

Jan 1, 2004

By William James Middleton

The life-cycle assessment (LCA) approach can be an important tool for the quantification and evaluation of environmental impacts associated with metal production systems. At the conceptual phase of a new metals development project, LCA can: ? Aid project decision making by evaluating the environmental consequences of design decisions ? Support project permitting and reinforce site/process environmental impact assessment ? Allow environmental impact comparisons between alternate flow sheets For existing metals production systems, LCA has been used to aid targeted process improvements by monitoring recent historical trends in environmental performance, either through local or external (externalities) process improvements. This paper discusses the life- cycle assessment methodology, and its application as a supportive tool for environmental decision-making in process design and operation, and for site environmental impact assessment and permitting. Selected examples from a recent LCA performed on the Pressure Acid Leach Process for treating nickel Laterite ores are employed to demonstrate the usefulness of the tool.

Jan 1, 2004

By A. Dell’Era, M. Pasquali, C. Lupi

"An electrochemical cell has been designed to treat very diluted cobalt solutions, i.e. those deriving from recycling processes of lithium-ion batteries. A reticulated vitreous carbon sponge was used as cathode and a Pt-coated Ti net as anode. A controlled potential electrolysis has been carried out in a solution flowing in the cell and maintained at a constant pH of 6.5. Considering the cathode dimensions (10.0 cm * 10.0 cm * 1.25 cm), rather high volumes of solution (>1 litre) can be treated with flow rates up to 1.6 l/min. The process yield is obviously related to the solution concentration; it has been observed that, starting with a solution containing 200 ppm of Co2+, the yield is initially ~35-40%, but it decreases to ~20% when 80% of the initial cobalt content has been electrowon. The yield increases up to ~50% if the carbon electrode is coated by cobalt. The conditions allowing a fast and complete removal of cobalt are outlined. Introduction Industrial liquid effluents containing heavy metal ions arise not only during hydrometallurgical processing, but also in many sector of chemical industries utilizing metal catalysts and process reagents. These waste solutions containing low quantities of metallic ions can be treated by chemical precipitation, solvent extraction, ion exchange, etc. before final discharge. All these techniques could be efficient for complying the aqueous effluents with the severe rules related to the environmental impact, but they can not directly produce metals. Particularly the chemical precipitation presents two main drawbacks, huge amount of sludge prodction and reagent costs to produce this useless and sometime dangerous sludge that have to be considered. Electrochemical technologies can be used for the treatment of effluents polluted by metal ions, showing the following advantages in comparison with other processes: 1. recovering of the polluting substances in metallic forms, with subsequent reusing; 2. absence of process slag, which should be subsequently disposed of. In this work an electrochemical reactor with a reticulated vitreous carbon cathode and a platinated titanium net anode has been designed and utilized for removal Co from waste aqueous solutions. Porous materials have been used as electrodes for this cell, as their high specific surface area favours the treatment of these low metal content solutions (1-7). This kind of electrodic material presents very interesting chemical-physical characteristics such as: low density, low thermal expansion and high electrical and thermal conductivities; particularly the reticulated vitreous carbon (RVC) presents a very elevated void volume, rigid structure, good resistance to temperatures in non-oxidizing environments and very low resistance to fluid flow."

Jan 1, 2008

By Brady Butler

Many high capacity metal hydrides exhibit a high degree of stability in the hydrogenated state. This stability leads to a number of significant design problems with regard to the low temperature kinetics and thermodynamics of dehydrogenation. Nanometric metal hydride materials provide a promising route for increasing the reaction kinetics while altering the thermodynamic stability of the material. The use of nanometric metal hydride materials for hydrogen storage has largely been absent because of the difficulties associated with the synthesis of these materials. In this paper, research results on the synthesis of lithium based metal hydrides by vapor phase reactions are presented. The lithium based compounds that have been made in our lab include nanosized powders of metallic Li, Li₃N, LiNH₂ and LiH. The vapor phase process has also been used to custom engineer Li-based materials with other alloying elements or doping elements. The dependence of the characteristics of these materials on synthesis process parameters is studied. The effects of nanoscaled particle sizes on the kinetics of dehydrogenation and hydrogenation reactions are also explored.

Jan 1, 2006

By E. M. Alcântara

This paper describes some aspects about the relationship between copper electrorefining addition reagents and the hydrogen in the cathode. The conditions of electrorefining were studied by factorial design methods. The advantages of this technique are reduction in the number of tests, well organized experiments; improvement in productivity and reliability of results. The dosage of the two main addition agents, glue and thiourea, were varied simultaneously and compared with the hydrogen content in the cathode. The influence of these factors, as well their interactions were analyzed by statistical methods denominated ANOVA (Analysis of Variance). The increase of thiourea quantities, within of levels studied, influenced significantly at 95% confidence in the hydrogen content in copper cathode.

Jan 1, 1999

By A. Cullaj

During a period of 15 years the metallurgical and chemical complex of Elbasan containing more than 15 principal plants, producing cast-iron, steel, coke, nickel carbonate, nickel, cobalt, chromium and other products, discharged into air, river water and soil an extensive amount of hazardous wastes containing high toxic substances. A monitoring study for the levels of heavy metals in soils nearby the former plant is carried out for the first time. Very high levels (total and extractable) of contaminants such as nickel, cobalt and chromium are found in samples taken from a relatively vast territory including the city of Elbasan, situated 8 kilometres far from the plant. The most polluted samples present a total content of 1211.8 ? 2949.6 mg/kg Ni, 97.0 ? 181.2 mg/kg Co and 1358.7 ? 4130 mg/kg Cr. These levels exceed several times the phytotoxic thresholds and present a potential hazard for the inhabitants. This study, as part of a bigger multinational project on solid decontamination, will also serve to the possible application of the new phytoremediation and phytoextraction technologies, being developed in parallel in this project.

Jan 1, 2006

By Ian M. Ritchie

Cementation or metal displacement reactions such as Cu2+ + Fe Cu + Fe2+ are among the oldest known hydrometallurgical reactions. They are still used in the recovery of some metals and in the purification of process liquors and waste water streams. However, they are often more complex than the stoichiometric reaction would suggest because they involve the simultaneous deposition of one metal onto a second which is dissolving. For example, sometimes a cementation will not take place, even though it is thermodynamically favoured. On other occasions, a cementation reaction will start but come to a halt as the depositing metal blankets the reacting surface. On yet other occasions, side reactions, catalyzed by the deposit, can be important. In this paper, the electrochemical basis of cementation reactions is described. The conditions for each of the complications encountered in these reactions are described and illustrated by examples drawn from a number of hydrometallurgical processes. The cementation reaction between activated carbon and gold thiosulfate is also briefly described, this reaction being unusual in that no dissolution of the carbon occurs.

Jan 1, 2003

By F. E. Katrak

Rare earths markets by definition usually include not only the rare earth elements, but also yttrium. They can be subdivided into a very large light rare earth fraction (about 95 percent by weight of all rare earths consumed) consisting mainly of cerium and lanthanum and a smaller fraction (with much higher unit value) consisting of selected high-purity oxides or elements such as yttrium, europium, samarium, or neodymium. CRA estimates that the noncomnunist world market for all rare earths and yttrim was on the order of US$750 million in 1986. The main focus of this paper is on the principal uses for rare earths, some CRA-developed proprietary data on their consumption by region, and the selective nature of business opportunities in the rare earth markets. We also provide forecasts on the future trends in these markets.

Jan 1, 1989

By Renaud Metz

The DOPA process (Direct Oxidation of a Precursor Alloy) was used to prepare ceramic powders based on doped SnO2 and ZnO. The DOPA process consists essentially in the direct oxidation of a homogeneous precursor alloy. A unique advantage of this process is its rather benign environmental impact since no dangerous reactants are used and no harmful by-products are generated. Only oxygen and the alloy metals participate on the chemical reaction to produce the multi-component oxide. Homogeneous alloys of niobium, cobalt and chromium doped tin have been prepared. The molten metal alloy is atomised in air using a double fluid nozzle to produce metallic powders. A subsequent thermal treatment is carried out to fully oxidise the sprayed metal alloy powders. These raw powders are used to prepare a ceramic powder through a mill homogenisation and atomisation process. The ceramic powder is then uniaxially compacted in disc shape and sintered in an oxidising atmosphere. The resulting sintered bodies are metallised on their flat faces and the cylindrical surface is passivated using lead free glass enamel. These ceramics present excellent semiconducting properties with non-linear (non-ohmic) characteristics. The DOPA process is found to be an attractive procedure to obtain ceramic powders for the preparation of SnO2 varistors.

Jan 1, 2006

By V. M. Paretsky

Most recent developments made in the Gintsvetmet Institute in the field of technologies and equipment for single-stage autogenous smelting of copper sulfide raw materials to produce white metal and blister copper on the basis of oxygen-flame smelting process and separation of highly basic calcium-containing slags have been discussed. This technology includes the oxygen-flame smelting process (KFP Process) to produce highly basic self-disintegrating ferrite-calcium slags with their subsequent flotation to recover copper and a basically new sparging smelting process (FBP Process) to produce combined slags subjected to decopperizing inside the same furnace. Results of special investigations of the slag structure obtained in the KFP and FBP processes and substantiating selection of their chemical and phase composition have been presented. It has been demonstrated that the above processes meet the stringent world-level requirements to advanced technologies with respect to energy conservation and environmental safety with different scales of production and within a wide range of specific conditions of particular operations.

Jan 1, 2006