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By Roald Ysteboe, Finn Olesen

"Elkem has developed a process that utilizes SPL as a raw material for pig iron production. This process will be demonstrated in industrial scale during 2008 and 2009. The process developed produce iron, and the reduction material used, is the carbon present in the SPL. The iron source could be either virgin iron ore or waste/recycled material from the steel industry. The SPLrefractory and bath material is dissolved in the slag produced. The slag is designed so that any leaching of environmentally dangerous elements is minimized. This process can in addition to SPL, consume other types of waste derived from the primary production of aluminium. Elkem intends to supply this demo project with SPL and other waste products from external sources, domestic as well as international ones.IntroductionSpent Pot Lining (SPL) is generated when an electrolytic cell for producing aluminium is taken out of service and the refractory and carbon lining is removed from the steel potshell.The yearly generation of SPL world wide is exceeding 500 000 tonnes. The major amount of this quantity is stockpiled or land filled, unprocessed.SPL contain large amount of water soluble fluorides and some amount of cyanides and is classified as hazardous waste in most countries."

Jan 1, 2008

By Andrzej Szymanski

Recent developments in medicine have stimulated activities that? involve mineralogy. They include inplantation of inorganic and organic parts into bones and soft tissues, and uses of elements as basic stimulators for the human body. In addition contamination of the environment has increased the concentration of sane elements in food. Consequently f both the environment and food structure vary with geographical regions and influence human health. These activities in medicine have created the new fields of biomineralogy and of biogeochemistry as activities for the future.

Jan 1, 1989

By M. M. Sadawy

"The increased rate of exploitation of iron ores has resulted in a rapid depletion of high-grade iron ore deposits in Egypt. New iron reserves have to be discovered to secure the iron ore for steel production. This paper aims to study the characterization and magnetic separation of low grade Aswan iron ore. The results showed that Aswan iron ore is composed of oolitic hematite, goethite, quartz and kaolinite. The screen analysis indicated that Aswan iron ore had a uniform distribution of iron and silica in the different particle size fractions and there is no any particle size has high amount of iron or low content of silica. On the other hand the results of dry high intensity magnetic separation illustrated that this technique is not suitable for upgrading this ore.IntroductionIron is one of the common metals used in industry, as well as being the fundamental raw material used in iron-steel industry; products are wide spread even in daily uses. The total iron ore reserves of the world have been estimated as 3 70 billion tones; 160 billion tones is classified as economical, while 210 billion tones as potentially economical [1]. An estimated 98% of the iron ore exploited in the world is used in the manufacture of pig iron and steel, which are non-substitutable backbones of modem society. The rapid increase of world steel production over the last few years have required an equal increase in iron ore production, from 876.8 Mt in 2006 to 948.1 Mt in 2007 [2]. The increased rate of exploitation of iron ores has resulted in a rapid depletion of known high-grade iron ore deposits. This, in turn, has led to a dramatic increase of prices. In the absence of any major new discoveries of high-grade iron ore deposits, mining companies have turned to lower-grade materials to assess their beneficiation potential to expand their production base and beneficiation capacity, in order to satisfy future demand. Egypt is going to face shortage in iron production, consequently new iron reserves have to be discovered to secure the iron needed for the country [3]. Exploitation of low grade ores requires special equipments and techniques for recovery of minerals values. High gradient magnetic separators offer promise and great potential of application both technologically and economically in the processing of fine particles containing weakly or feebly paramagnetic components [4-6]. Within this existing framework, this research was initiated to assess the beneficiation potential of low-grade Aswan iron ore by high intensity magnetic separation."

Jan 1, 2013

By Stefan Mutl

By the term sorting one understands the separation of a material mixture into two or several products according to different material characteristics in the preparation technology. The oldest sorting procedure, the handpicking, is less and less used to separate different material mixtures because of the considerable personnel expenditure and the strict hygienic regulations at the workplaces in Europe. In general, the manual assortment is able to solve separation tasks, which could not be solved by machines so far. The picking is one of the most selective processing methods. However, the progress in the computer and sensor engineering today makes the creation of automatic picking devices possible, whose efficiency goes far beyond the possibilities of handpicking. Therefore in the future automatic picking will not only be applied to already common applications like the waste glass assortment by colour, but also to the assortment of complex composed material mixtures e.g. old shreddered cars. Thus, the automatic picking, supported by high performance computer systems and new sensor technology, gains more and more significance within many applications of waste processing. However, in order to apply automatic sorting procedures for different material streams within recycling processes, a substantial research and development need still is existing. The desire of the users is to sort more extensively in order to achieve products with bigger material varieties, In addition, the requirement of the accuracy of recognizing and sorting out of single grains rises, This lecture illustrates the procedure of the hand picking before it was employed in waste processing. Thus, a renaissance of a long forgotten method is happening in terms of today's state of the art procedure "automatic picking". Possible technologies, fields of application and future potentials of this technology are pointed out.

Jan 1, 2003

By Jonathan A. Paul

The most profitable companies in the world recognize that a huge competitive and financial power lies in their intangible assets. The competition to be in command of raw materials and markets is now waged more and more over the exclusive rights to new technology and ideas. The value gained from mining the innovation in your organization and protecting your intellectual property can be enormous. This paper will address the following topics: ? Understanding the connection between your competitive position and intellectual property ? Determining the value of your current portfolio and strengthening protection ? Converting knowledge into assets and adding value to the operation ? Litigation strategies to enforce your position and achieve your business objectives The presentation is designed for company executives and government managers who need to know how to identify and address core intellectual property issues that arise in the minerals, metals and materials extraction and processing industries.

Jan 1, 2006

By M. Hadj Meliani

This paper explores direct use of finite element analysis by CASTEM 2000 in order to determine the evolution of T-stress term for arc of pipe specimens with external surface crack. A simple method, called the stress difference method proposed by Yang (1999), is used to compute the elastic T-stress in mode I at a crack tip. The different crack geometries and length-to-thickness ratio on T-stress and stress-intensity factor (SIF) are examined. The revisited stress difference method is shown to be an accurate and robust scheme for evaluating T-stress in arc of pipe.

Jan 1, 2006

By Enrique Posada

"The Valle de Aburrá area, corresponds to the city of Medellín and neighboring municipalities, with more than 3 million people. The area generates a sizable amount of solid waste, which has been taken to landfills for the last 20 years. This paper proposes a model for public policy making which considers the cost and benefit of different alternatives to handle the wastes in the coming 20 years. Combinations of several alternatives: Recycling, waste reduction, waste separation, incineration, land filling with lixiviate treating and gas energy recovery, and organic waste composting are considered and modeled and the results presented as a contribution for a more rational approach to policy making than the one currently being employed.IntroductionThe author, working for INDISA S.A., acted as a consultant for the direction of planning of the Empresas Varias de Medellín in 2004. This entity has the responsibility for the handling of the solid wastes of the city of Medellín and some of the neighboring municipalities. At the present time more the 700.000 annual tons of waste are taken to the site of La Pradera, located in very rainy location (3.000 mm of precipitation per year), with complex in topography and very far away from the sources of the waste. During the work the author detected important problems that should be addressed, as follows:Lack of adequate technical administration and resources. The entity did not count with sufficient human resources to focus on the appropriate technical handling of the solid waste. The organization worked mostly with independent contractors, lacking enough coherence and integration. The internal workload was too large for the few people who had technical responsibility and this gave rise to attention problems. It is important to have clear technical procedures, technical know how and human resources, continuity in the activities. It is important to have a clear capacity to plan, to study, to make tests and monitoring, to pursuit and develop ideas, to optimize the processes and to introduce changes, to respond to environmental authorities, to the communities and to mass media and to handle the contractors. All this was basically lacking. In the case of the handling of the sanitary filling of La Pradera, for example, although the people in charge were very able and dedicated, the magnitude of the task was too large and the resources they had were insufficient. As a result, the site had at the time of the study, problems with thousands of vultures, lack of immediate cover up for the waste, uncontrolled leaching, the area being dirty and little attractive, despite being called a park."

Jan 1, 2008

By J. H. Meza

La Caridad copper smelter is located in the magnificent but rugged Sierra Madre Mountains. This project presents unusual challenges that require the utmost in detailed analysis and planning. The smelter, owned by Mexicana de Cobre, S.A. de C.V., has an annual production capacity of 225,000 metric tons of copper and 600,000 metric tons of sulfuric acid. It utilizes only the Flash Smelting process. This project will expand the annual production capacity to 270,000 metric tons of copper and 1,000,000 metric tons of sulfuric acid. Offgases from the Flash Furnace and the Teniente Converter will be sent to a mixing chamber, from which it will be led to two sulfuric acid plants. This project will then produce a high quality sulfuric acid.

Jan 1, 1995

By Wantae Kim

In order to establish the optimized recovery process for heavy minerals from Korean beach sand, we investigated the several physical separation methods such as gravity and magnetic separation followed by mineralogical characterization. There was clear relationship between the particle size and heavy mineral content that heavy minerals were mostly concentrated in the particles below 100mesh. Gravity separation using the spiral and shaking table separators made it possible to concentrate heavy minerals by rejecting the light and coarse particles consist mainly of quartz and other non-valuable minerals. The high-intensity magnetic roll separator and subsequent induced magnetic separator were applied to fractionate magnetic particles according to their magnetic susceptibility. The content of TiO2 of high susceptible ilmenite-rich fraction was 43.98wt.% while those of ZrO2 of non-magnetic and magnetic residue were 6.78wt.% and 3.11wt.%, respectively.

Jan 1, 2006

By A. V. Tarasov

Based on the data available in the literature and the practical experience of new metallurgical plants, a method has been proposed and relevant studies conducted for metallurgical processing of zinc sulfide concentrates. Process conditions and parameters have been identified, which ensure high levels of recovery of zinc into solution. This is achieved by leaching concentrates under the normal pressure at a temperature of >90°C in the presence of ferric iron ions. Sulfide sulfur is converted to elemental sulfur in this process. To produce elemental sulfur it is necessary to maintain oxidizing conditions in the system, characterized by a positive Eh value. In order to eliminate the interfering effect of elemental sulfur formed in the process, it is possible to add surfactants into the concentrate pulp. The proposed technology has certain advantages as compared with the high-temperature pressure leaching and is considered as a basic technology to be applied to increase zinc production at one of the Russian zinc plants.

Jan 1, 2006

By Partha Patra

Extracellular bacterial protein (EBP) from Paenibacillus polymyxa was isolated. Adsorption of bacterial cells of Paenibacillus polymyxa as well as EBP onto pyrite, galena and sphalerite was studied. Both bacterial cells and EBP was found to have different adsorption density for different minerals. Protein from mineral surfaces were extrated and examined through SDS PAGE electrophoresis. Specific group of protein was found to be adsorbing, specific to respective minerals. EBP was fractionated through FPLC. Adsorption studies were carried out with each fractions. Difference in adsorption density was observed for individual minerals. Flocculation and flotation experiment were carried out with these mineral specific EBP. Pyrite was selectively removed from ternary mixture of galena and spharite through flocculation anf flotation using pyrite specific EBP. Mineral specific EBP was found to selectively separated remove pyrite from the complex sulphide mixture.Zetapotential studies were carried out to examine the surface chemical changes of the minerals on interaction with EBP. Hydrophobicity of the minerals were carried out on interaction with bacterial cells as well as mineral specific EBP.

Jan 1, 2006

By Larry G. Stolarczyk

The development of geosteering technology for geothermal reservoirs is challenged by the integration of electrically small antennas in small-diameter metallic drill rods. To be useful, the antenna pattern must achieve sufficient back-lobe suppression, preferably with a forward-looking pattern. Forward-looking capability requires an antenna array with phase control. The phase-controlled antenna pattern enables imaging of geologic structures ahead of and surrounding the well bore. This paper describes the development of electric and magnetic dipole arrays for small-diameter drilling pipe.

Jan 1, 2006

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 A. H. Rosenberger, M. A. Tschopp, M. A. Groeber, K. N. Solanki, A. L. Oppedai, J. D. Miller

"Characterizing the spacing of primary dendrite arms in directionally-solidified microstructures is an important step for developing process-structure-property relationships by enabling the quantification of (i) the influence of processing on microstructure and (ii) the influence of microstructure on properties. The research objective herein is to evaluate the capability of various conventional approaches, as well as new or modified approaches, for spatial point pattern analysis with application to characterizing experimental dendritic microstructures. Both computer-generated and experimental dendritic microstructures are used for this analysis along with numerous techniques based on the nearest neighbor spacing, Voronoi tessellation, Delaunay triangulation, or graph theory. Comparison of new metrics with traditional primary dendrite arm spacing metrics will also be discussed for both local and global measures. The current methods investigated will supply information of local spacing and coordination number while addressing edge effects, parameter sensitivity, and correlation with interdendritic features, thus providing insight into how processing affects properties.IntroductionDeveloping an enhanced understanding of mechanical behavior in materials relies upon sufficiently characterizing microstructure details at the relevant length scales that contribute to this behavior. Moreover, to truly enhance the predictive capability of processing-structureproperty models that aim to improve material performance requires a quantitative description of the relevant microstructure features and, thereby, the material itself"

Jan 1, 2013

By Hiroyuki Sano

Elimination of heavy metals from the incineration fly ash by the chlorination volatilization method had been already developed and the effectiveness of this method was confirmed by the present authors. In this study, this method was applied to the elimination of heavy metals, mainly lead, from the incineration bottom ash. Since the fly ash contains a large amount of chloride, heavy metals in the fly ash are easily chlorinated. On the other hand, the addition of the chlorination agent is a key point for applying this method to the bottom ash, because it hardly contains chloride. The effects of various variables such as a kind of chlorination agent, adding quantity of it and temperature on the elimination ratio were investigated and the harmlessness of the residual ash was evaluated. The preferable condition was proposed from the recyclability of the bottom ash.

Jan 1, 2006

By L. A. Kazanbayev

The Chelyabinsk Electrolytic Zinc Plant (CEZP) was commissioned in 1935. Over the elapsed years the Plant capacity has been increased from 10 thousand tons of zinc (1935) to 150 thousand tons of zinc (2005). The paper describes the Plant main achievements in production updating for the last 10 years.

Jan 1, 2006

By Kazutaka Kunii

It is invariably certain that after punching for IC Leadframes, scrap metal were generated. These seraps were re-dissolved and in order to use as raw material for leadframes, it is necessary to remove the Ni plating. In this study a simple method was developed for the removal of Ni plating by surface oxidation of Ni plating. For this purpose a fundamental study was carried out on the oxidation behavior of Ni plating. Results showed that by controlling the oxidation condition, a considerably high rate of Ni could be removed.

Jan 1, 1996

By Chengyi Ding, Xuewei Lv, Changyang Ji, Rende Zhang, Xiangwei Zheng

The fraction of liquid phase in sintered ore can be the most important factor to determine the sinter quality and yield in sintering process. The generation ability of liquid phase for mixture of iron ore powders is determined by basicity, roasting time, roasting temperature and chemical composition of iron ores. Five different iron ores were selected in this study and the dried powders of iron ore and CaO reagent (<200 mesh) were homogeneously mixed together at their required proportions, then 15g of the mixture was pressed under a pressure of 20MPa to make a cylindrical sample with a diameter of 20mm. The sintering temperature in this study was kept at 1280℃, the gas phase is air, the holding time was varied with its three levels of 5min,10min and 15min. After that, the sample was cooled under room temperature in the air, and the cooled sample was analyzed by using zeiss optical microscope. The mineral phase compositions were quantitatively determined with an open source image processing software, Image J whicn can calculate the fraction of liquid phase. Besides, the study on how to estimate the sintering behavior of the raw materials in different conditions by the theoretical calculation is of vital importance, and the development of this will greatly improve the sintering production. Factsage will be used to calculate the liquid phases formulation during the sintering. Comparing the experimental results and the theoretical calculation shows that the mass of liquid phase increases with increasing basicity during the sintering, besides, the mass of calcium ferrite increases with increasing basicity. The generation ability of liquid phase of iron ores can be predicted through the experiment verification.

Jan 1, 2015

By W. Mueller

The function of a process mineralogist in the operation of a copper mine and plant is to assist in the identification and classification of the operation&apos;s main throughput. These include ore, concentrates, slag and matte, and to a lesser extent, refined products. In addition, a number of other products not normally thought of in association with mineralogy are examined. These include scales from submersible pumps, failed boiler tubes, acid plant, and shaft furnace; characterization of inclusions in failed compressor gear teeth as well as in copper rod; and flue dusts from a smelter, air transported particulates and coatings on passive copper anodes in the refinery. Techniques and equipment required for these studies include simple hand magnets to the high intensity Isodynamic separator, visual examination to electron microscopes, x-ray equipment, DTA, IR, heavy liquid separation, and contracted services of custom laboratories. Several examined products from Magma Copper Company have been selected to illustrate the range of techniques and equipment required by a process mineralogist.

Jan 1, 1981

By Carla Lupi, Alessandro Pescetelli

"Spent lead battery recycling still shows few weak points in the achievement of a 100% recycling of different waste matters and by- products arising from the recycling process. Some of said problems are dealing with aqueous streams outgoing the recycling plant, and more particularly, a) the waste waters discarded from the breaking and separation unit, b) purification of the spent electrolyte drained from waste batteries and upgrade to a quality compatible with full re-use by the batteries’ manufacturers, c) purification of the mother liquors discarded in the sodium sulfate crystallization process so to produce a salt of commercial grade. All of the above listed problems have been satisfactorily overcome applying an electrochemical process that, through different process conditions and parameters, is able to remove the harmful impurities that hinder the successful commercialization of such by products, or, at least, that can avoid heavy and expensive treatment plant and operation.IntroductionAlmost 100% of commercial lead and lead alloys produced by secondary lead plants is recycled to the new lead accumulators manufacture. The other by-products and residues produced through the lead recycling process may be classified into two groups:a) matters reusable in the new accumulators production processb) matters produced as a result of various reagents and additives used in the recycling process, to be sold to different market sectorsQuality and saleability of by-products are significant points for the economics of the secondary lead plant operation, because, if said by-products are not saleable, they are just wastes, so offsetting potential revenues, and, at the same time, adding a heavy burden to operating cost, like disposal cost [1]. When looking at a typical, modern lead scrap batteries recovery cycle, it is quite evident that we are still rather far from dealing with a waste-less technology (fig.1).The group a) includes 3 by-products produced through the breaking process: among those matters the polypropylene only usually reaches a standard quality suitable for sale to lead manufacturing sector or to other sectors as well. The other two by-products, electrolyte and separators, do not still reach, through a viable and effective regeneration process, a quality standard sufficient for their re-use in the lead batteries sector ."

Jan 1, 2008