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By R. Laucournet, E. Billy, M. Joulié

Today Li-ion batteries are considered as one of the most attractive available energy storage solutions. However in order to overcome environmental, legislative and economic issues, the management of used batteries has to be considered and mainly the recycling. The present paper deals with the recycling of used Li-ion batteries and the recovery of high value metals from active materials of electrodes. Lithium nickel cobalt aluminum oxide (NCA) and lithium manganese nickel magnesium oxide (LMNM) cathodes, which contain most of valuable elements typically used in the composition of active materials for Li-ion batteries are investigated by a hydrometallurgy route. The process is divided into two steps: the materials leaching and the elements recovery by a selective chemical separation. Some experimental parameters (acid nature, concentration, time and temperature) are studied to determine the most efficient conditions of dissolution. Then, the valuable elements such as nickel, cobalt and manganese are selectively recovered with a high efficiency close to 100 % and with a high purity by precipitation. By this study, an adaptable hydrometallurgy process can be defined according to the composition of Li-ion batteries to recycle.

Jan 1, 2014

By Katsunori Yamaguchi

A new technique for the removal of tramp-elements from steel scrap has been required from the viewpoint of saving energy and protection of environment. In order to obtain fundamental information on the removal of copper, tin and zinc from molten iron, the extraction method by using of phase separation in the liquid Fe-Pb-C system was investigated at 1453K. A mixture of iron, lead and carbon melted in a carbon crucible separates into two phases of lead and iron containing carbon. The compositions on the miscibility gap in the Fe-Pb-C system are 95.4%Fe-4.5%C-0.1 %Pb and 99.9%Pb-0.I%Fe. The distribution ratios of copper, tin and zinc between the lead and the iron phases, Lx [mass%X in molten Pb]/(mass%X in molten Fe), are 2.2, 2.2 and 1.4, respectively. Seventy percent of copper and tin from iron scrap can be eliminated with comparable lead addition. Gold, silver and palladium are enriched in the lead rich phase, on the contrary platinum and rhodium are more distributed to the iron rich phase than to the lead phase.

Jan 1, 2003

By A. Delgado-Jiménez, O. J. Restrepo-Baena, G. Aristazabal

"Mining industry as a source of raw material is essential to society however, it lacks of good reputation due to the type of management historically applied to many of its social and environmental impacts. It is argued that this situation has hampered the obtaining of social license to operate of a lot of mining projects around the world. The last considerations are very common in Latin American countries. As a result, the mining sector has understood that the viability of the business long term is associated with more profit for the shareholders but also with activities that improve the livelihoods of local communities, enhance the capabilities of local governments and preserve the ecosystems around the projects. Nevertheless, recent studios have shown that most of the current advances to incorporate sustainability concepts in mining have been mainly focused on control and the prevention of environmental and social impacts of extractive activities. Thus, contributing to the development of territories around mining projects constitutes a fundamental aspect of the business competitiveness through reducing cost and risks of stopping projects, innovating new ways of relationship with stakeholders, improving the level of reputation of the industry as well as its position in the market. However, this contribution requires formal strategies and models that enable companies understand the different resources in the territories where their mining activities are developed and those resource transformations, in order to establish the best way to articulate the project with the territory, pursuing an effective contribution to its development, truly sustainable over time even after the mine closure. CONTEXT Currently in the world but especially in developing countries such as Latin Americans, different stakeholders are increasingly vigilant of how mining companies carry out their activities in terms of socio-economic and environmental management of territories, not only for its impact on the livelihoods of the communities that inhabit them, but also because many demanders of raw materials -both countries and companies- have set sustainability standards as a prerequisite to establishing business relationships with mining companies, such as the recently declared Sustainable Development Goals by 2030 (UN, 2015). Accordingly, decide underinvest or not to invest in sustainability issues carries risks for mining companies. However, invest much in the wrong way may involve the same risks. Managers are concerned to ensure profits, and therefore they decide carefully how to invest in the areas of production, R & D or marketing. Likewise, they should think strategically about investing in initiatives related to sustainability. This if they really want that those investments in fact help to improve the competitiveness of the company. The mining industry benefits from natural capital that extracts, so it should implement strategies that lead to remunerate such benefit to the territories (Almaguer, 2007). One option is through the transformation of natural capital in other types of non-existent capital or poorly developed in their areas of influence. In this way, the value generated by the extraction of underground resources is shared and additionally contributing to improving the quality of life of the communities. Historically, mining industry has been into several problems to achieve this, which represents one of the aspects that has most influenced the current reputation of mining industry in some regions of Latin America. Many communities, local governments and civil society organizations continue to associate this activity with the destruction of the social fabric and ecosystems in the territories, and their opposition against companies working in the areas has led to affect the operational continuity of many projects (Hamann, 2003; Prno and Scott, 2012; Slack, 2012)."

Jan 1, 2017

By Theodore J. Barrett

[One of the earliest records of pillar removal can be found in the 16th Chapter of Judges in the Old Testament. Here we read where the mighty Sampson removed the pillars from beneath the prison house causing the collapse of the structure resulting in his own death along with the deaths of the 3,000 Philistine occupants. Our problems at the Mi Vida Mine differ somewhat from those of Sampson of old, in that it is our aim first to remove the pillars and get out from under the back before the "house falls in" and, secondly, to remove the pillars without the lose of a single life or without even a single casualty. As of January 15, 1959, the Mi Vida accident record stood at 772 days without a lost-time accident]

Jan 1, 1959

By Suresh K. Bhatt

Although overall worker productivity for U.S. underground coal mines is available, productivity by mining method and seam thickness is not. Mining technology has gone through dramatic changes in the past decade, and the industry has experienced a lack of accurate productivity Figures addressing these changes. This information is of great interest in planning for future mining systems as thick and shallow coal seams currently being mined are depleted and exploitation of thinner, deeper, and better quality seams is considered to partially meet the requirements of the 1990 Clean Air Act Amendments. In a cooperative program, the U.S. Bureau of Mines obtained raw mine level production and related data from U.S. Energy Information Administration for 1989 and 1990 and performed the needed statistical analysis. Base criteria, parameters, and salient results of the mine productivity analysis are presented in this report.

Jan 1, 1994

By S Vearncombe

SpaDiSÖ is a revolutionary approach to the spatial analysis of point data using geometry to analyse geometry! SpaDiSÖ uses each and every spatial relationship and is not dependent on mathematical models. For n points there are n2 û n spatial relationships and, because of the square function, the method yields interpretable results for both small and large data sets. SpaDiSÖ is an alternative to variography for directional studies. At the regional scale, the analysis can assess distribution patterns of mineralisation and potential controlling structures. At the deposit scale, the characteristics of zones of mineralisation such as direction, spacing, high-grade ore direction and grade distribution can all be deduced.

Jan 1, 2000

By W. S. Eu

Reduction of weathered mineral ores can initiate phase transformation which can affect either their activation or deactivation, subsequently influencing the extent of extraction of desired metals in a leaching reagent. The reduction of ilmenite ores for one occurs as a series of parallel, solid state reactions which at present has no known mechanisms, although the evidence of their effects is abundant. Understanding these reactions may well be the key to uncovering the mechanism of ilmenite activation, hence enabling precise control of its reaction process to maximize yield of TiO2 extraction. However, documenting the solid state reactions in the reduction of ilmenite is challenging due to the ore complexity, the number of simultaneous reactions and the difficulty of capturing critical intermediate reactions and phase transformations during processing. The phase transformations of ilmenite minerals reduced at temperatures up to 850°C were investigated in this study. Mineral transformations were studied in-situ using synchrotron radiation based X-ray powder diffraction with temperature resolved tests. The effect of the extent of reduction and specific mineral transformations were verified by leaching reduced ore with sulphuric acid. The re-sults suggest that transformation of major mineral phases occurs within of specific window of operation and thermal treatment appears to influence the extent of activation and leachability of ilmenite minerals.

Jan 1, 2014

By John M. Smith

Kaolin is an important industrial mineral because of its unique properties and low cost. Strictly defined, kaolin is the name given to a group of hydrous aluminum silicates of which kaolinite is the most common mineral (1). Through common usage the mineral, kaolinite, is called "kaolin" or "china clay". In 1972 over 4, 000, 000 tons of kaolin will be beneficiated and shipped by domestic producers. By far the largest user of kaolin is the paper industry which utilizes approximately 65 to 70 per cent of the total production. Kaolin is used in paper as a filler in the interstices of the sheet and as a coating to impart smoothness, gloss, brightness, and printability to the paper. The rubber industry is also a large user of kaolin where it is used as a filler because it adds strength, abrasion resistance, and rigidity to both natural and synthetic rubber goods. Kaolin is used as an extender in paints because it is chemically inert, has a high covering power, gives desirable flow properties, and is low in cost. In ceramics, kaolin is used in whitewares, tile, insulators, refractories, and in some face brick where a white color is desired. Kaolin is also used extensively in plastics as a filler in thermosetting and thermoplastic mixes to give smoother surfaces, a more attractive finish, good dimensional stability, and resistance to chemical attack. Many other process industries use kaolin as a filler, suspending medium, or for color improvement.

Jan 1, 1972

By A. Janwong

Ion exchange technology is becoming more prevalent for metal recovery from low concentration solutions. The products of ion exchange are typically a metal free stream (product stream) and a concentrated metal stream (byproduct). The metals in the concentrate stream are usually precipitated and returned to the process or discarded. The unique features of emew® technology enable metals to be recovered directly from the concentrated stream. The advantage of the IX-emew® combination is the ability to have two product streams: 1) clean metal free solution and 2) metal product for sale. In addition to recovering metals from solution, it is also possible to separate metals from each other and recover more than one metal product. In this paper, examples of IX-emew® combinations are detailed including the recovery of copper, nickel and cobalt from an industrial waste stream, recovery of nickel from a spent electroless nickel plating solution and recovery of cobalt from an hydroxide cake.

Feb 23, 2014

By T. A. Vivian

The use of heavy media organic solvents to recover coal from its attendant gangue is hardly new. DuPont built a pilot plant using pentachloroethane in 1936 at Weston Coal Company, Weston Breaker, Shenandoah, Pennsylvania. That's almost half a century ago. Since that time, it has become common practice to utilize similar classes of chemicals in laboratory separations of coal samples. It is the objective of this paper to discuss some specific separations on both pilot and laboratory scale on samples representing different classifications of coal. These separations have been carried out on coarse (+4 M), middling (4 x 20 M), and fine (-20 M) coal samples. The coal samples tested include Pennsylvania anthracite; Pennsylvania, Indiana and Colorado bituminous; Wyoming sub-bituminous; and Texas lignite. Other chlorinated solvents were used to vary the specific gravity of separation.

Jan 1, 1984

By Xuling Chen, Yi Wang, Xiaohui Fan

"The current control method of grate-kiln iron ore oxide pellet production is lack of accuracy and normalization due to the limited detection conditions. Therefore, mathematical models of grate-kiln temperature field are presented. With calculation of gas-particle heat transfer as well as enthalpy changes of moisture evaporation and magnetite oxidation, the thermal history of pellets throughout grate-kiln process can be acquired and used for production status estimation. Taking the calculated results as well as detected data in production as inputs, process parameters such as running speed, fan opening and coal injection rate as adjusting objects, expert system for grate-kiln pellet production is outlined. And the preheating section dominated control strategy is explained. Results of production application show that the stability rate of gas temperature in gas hood of preheating section is increased from 91.0% to 94.2%, compressive strength and first grade rate of pellet are increased by 3.62% and 2.36%, respectively, while FeO content is 18.18% lower. Control guidance of this expert system can solve production anomalies effectively, stabilize grate-kiln iron ore oxide pellet production and improve pellet quality.IntroductionSteel industry in China has developed rapidly in recent years. China’s crude steel production in 2010 is nearly 627 million, which is 44.2% of the world total production. Burden with higher quality is demanded by enlargement and modernization of blast furnaces. And oxide pellet production has become a growing concern. In 2010, the total production of pellet in China is 110 million, and about 60% is produced by grate-kiln process."

Jan 1, 2012

By James R. Myers

A source of clean gas containing sulfur dioxide and sufficient oxygen for conversion to sulfur trioxide is essential to the production of sulfuric acid. SO2 containing gases obtained from roasting sulfide ores are heavily contaminated with inorganic dust and volatile impurities. If not removed, these contaminants will reduce product acid quality, foul the catalyst beds and mist eliminators, and accelerate equipment corrosion. This paper reviews conventional gas cleaning systems for metallurgical acid plants, followed by a discussion of modern systems utilizing DynaWave Scrubber technology. This technology is based on a unique approach togas scrubbing that can concurrently accomplish several gas cleaning/processing tasks. Scrubbing liquid is injected into the gas stream to create a "Froth Zone". This is a region of extreme turbulence, with a very high rate of liquid surface renewal. It efficiently removes both particulate matter and gas contaminants, and is also a cost effective quenching device for gases as hot as 1250 o C.

Jan 1, 1992

By R. ?. Shishmarjov, Yu. ?. Davidenko, S. V. Bukhalov, ?. S. Baksheev, M. S. Shkirya, N. ?. Aikasheva, D. V. Bogdanovich, ?. Yu. Faustova

"The goal of prospecting operations in the Republic of Altay was to locate gold-sulfide-quartz mineralization. For this purpose we applied the technology of electromagnetic sounding and induced polarization (EMS-IP). These operations resulted in localizing promising sites with presence of sulfidization. The EMS-IP method proved to be highly efficient amongst other prospecting methods targeted at recognizing zones of sulfide mineralization making up 91%, considering that in more than half cases the ore intervals were the case. In the Yakutian diamondiferous province the EMS-IP technology was approbated during three field seasons to accomplish the assignments on searching for kimberlite bodies under conditions of various geological types. As a result, the reference objects were distinguished, and geoelectric parameters of kimberlite pipes of explosion were defined.INTRODUCTION In the time span 2015-2016 in Gorny Altay the EMS-IP technology was approbated in the Novokuznetsk area. The on-land areal geophysical survey was performed by EMS-IP method applied to identify, outline and locate promising sites with Au-Ag-bearing polymetallic mineralization within surveyed areas. Compared to the hosting rocks, the sulfides contained in polymetallic mineralization are typified by low specific electrical resistivity (SER) and high polarization. The areal survey conducted via EMS-IP method provided spatial characteristics of searched object. From July 2016 to August 2017 our expedition group carried out serial test works and laboratory investigations intending to define performance capabilities of EMS-IP technology in searching for kimberlite bodies under conditions of diverse geological types. The prerequisites for serial work were operations accomplished at the «Listvenichny» site lying 35 km away from Mirny town in the Sakha Republic (Yakutia), where the EMS-IP technology was probed for locating position and measuring geoelectric parameters of tuff pipe «Buardakhsky». After successful completion of operations it was decided to evaluate geoelectric parameters of kimberlite pipes of explosion."

Jan 1, 2018

By R. Kumar, N. R. Mandre

"The beneficiation of iron ore slimes by selective flocculation was studied. Polyacrylamide (PAM) and guar gum were used as flocculant, along with sodium hexametaphosphate (SHMP) as a dispersant. The samples collected were initially subjected for chemical and mineralogical studies. The mineralogical studies indicated the presence of haematite and goethite as the principal iron-bearing minerals, with quartz and kaolinite as gangue minerals. The selective flocculation tests showed that the Fe grade can be enhanced from 58.24% to 64.60% Fe at a recovery of 66.33% using polyacrylamide as the flocculant. A Fe grade of 63.20% at a recovery of 68.04% was obtained using guar gum as flocculant. The efficacy of the studies was analysed using a separation index, which indicated that the higher separation index was obtained with the tests employing polyacrylamide as the flocculant. IntroductionIndia is endowed with huge reserves of highgrade iron ore and is one of the prominent producers in the world. As the high-grade iron ores have been exhaustively mined, it has become imperative to use low-grade iron ores, fines, and slimes to meet the growing demand. Also, generation of fines and slimes during mining and processing contributes to loss of minerals to the extent of 30% of the total value (Mandre and Panigrahi, 1997). These fines/slimes are often discarded as waste into tailing ponds, containing considerable amounts of iron. Therefore beneficiation of tailings/slimes has become necessary for optimal utilization of the resources.In recent years, interest in recovery of valuable minerals from low-grade ores, slimes, and tailings has increased worldwide. These activities are initiated not only to recover minerals but also to address various environmental issues associated with fine particle treatment. The literature reveals that several technologies have been employed in this regard, including flotation, advanced gravity separation, and high-intensity magnetic separation. However, these processes are found to be ineffective for fine particle treatment due to lower collision probability in flotation, decreased gravitational effect in gravity separation, and reduced drag force in magnetic separation, among other factors (Batisteli and Peres, 2008; Das et al., 2007; Dworzanowski, 2012; Rocha, Caneado, and Peres, 2010). Therefore, it is in this regard that selective flocculation has gained importance in treating slimes in recent years."

Jan 1, 2017

By C. A. Lorenson

THE Marmoraton mine is located a mile southeast of Marmora, a village in Hastings county, Ontario, 130 miles east from Toronto and 143 miles west of Ottawa. Highway No. 14 from Belleville intersects Highway No. 7 at Marmora and the branch line of the Canadian National railway between Trenton and Bancroft passes through the property just east of the open pit. HISTORY AND GEOLOGY The Marmora orebody appears as the whorls of a thumb print on the aeromagnetic survey map released by the Ontario Department of Min.es early in 1950, the survey of the district having been made in 1948 and 1949, under the joint auspices of the Department of Mines and the Geological Survey of Canada. The 'anomaly' appeared to have interesting possibilities, so Bethlehem representatives carried out a ground survey and began drilling the property in June, 1950. A total of 40 holes, aggregating 37,000 feet, were drilled to delineate the ore-body. The Marmora orebody is a re-placement of Precambrian limesto.ne with zones or bands of magnetite interlaid with metamorpl1ic rocks and cut by later intrusives. The ore and associated Precambrian rocks are overlain by 100 to 150 feet of flat-lying Palaeozoic limestone. It is a low-grade deposit averaging 33 per cent iron and requires concentration to raise it to 65 per cent iron grade.

Jan 1, 1958

By G. A. Witwicki

"The Thyssen Mining Group of Companies has successfully applied ground freezing technology to numerous projects throughout Europe and North America for over 100 years. Recently, the aspect of data acquisition and data verification has received greater focus.Thyssen Mining has been engaged in several relatively deep shaft sinking projects over the past five (5) years, all of which have required ground freezing to successfully sink through water bearing rock. To safely and economically sink through a quantity of water similar to Saskatchewan’s Potash Mines, it is imperative to understand freeze wall thickness and growth rate.Critical to understanding freeze wall thickness and growth rate, is the collection of accurate data as well as the interpretation of those data. The data can then be utilized to gain a better understanding of the freeze wall growth rate in active projects as well as to provide data to be utilized in modeling for future projects.This paper elaborates on the installation and operation of the data acquisition system utilized at the Newmont Leeville project, Nevada’s first frozen shaft project. In addition, this paper elaborates on the methodology developed by Thyssen Mining to manipulate the freeze wall data derived through the data acquisition system.The successful incorporation of the new system of collection and analysis of freeze wall data for the Leeville Project has given Thyssen Mining a high degree of confidence in the understanding, as well as prediction, of the ground conditions during shaft sinking.This paper will include:•,A brief description of ground freezing and its objective;•,An overview of previous data acquisition methods employed;•,Current data acquisition methods;•,Installation requirements; and,•,Data manipulation and presentation methods."

Jan 1, 2015

By Gopalakrishna B. Prabhu, David L. Bourell

"Three mol% Yttria-Stabilized Tetragonal Zirconia (YSTZ) was prepared by a sol-gel synthesis technique using zirconium tetrachloride and hydrated yttrium chloride precursors. After drying and annealing at 823K, the particle size was in the range 10 to 20 nm. The zirconia powder was sintered using a uniaxial hot press at an applied stress of 20 to 40 MPa. One hour, isothermal sintering was performed in air after initial heating at 50K/min. Theoretical density was obtained at densification temperatures above 1498K. After sintering, grain coarsening characteristics were studied using constant heating rate anneals followed by quenching, based on a model for grain coarsening in a linear heating rate cycle. The microstructural change was studied using SEM and TEM and the phases were determined using x-ray diffraction.IntroductionThe ability to sinter nanocrystalline materials to full density several hundred degrees below the normal sintering temperatures is one reason for their current interest. [1-5] Yttria Stabilized Tetragonal Zirconia (YSTZ) of grain size of about 300 nm has exhibited superplasticity, with elongations as large as 800%.[6-7] Fine grain size is critical for superplasticity. Retention of the fine grain size during sintering of nanocrystalline powder is important if a material is to exhibit superplasticity or to exhibit physical or mechanical properties associated with the ultra fine structure. This paper investigates the sintering behavior and the grain coarsening characteristics ofnanocrystalline YSTZ.Techniques for synthesizing nanocrystalline materials have been studied in great detail earlier. [8-12] The techniques used to synthesize nanocrystalline zirconia include alkoxide synthesis [9], the chloride method [11], the peroxide method [13] and the acetone-toluene method. [13] In this paper the method used in the synthesis of zirconia is the chloride technique. With this precipitation technique, either zirconium chloride or oxychloride and a corresponding yttrium salt or even pure yttria are used."

Jan 1, 1994

By F. Rashchi, N. Naseri Joda

Recycling of electronic wastes is an important subject both from an environmental point of view and also the recovery of valuable materials. In this research, PC board scraps were leached to recover Cu, Ag, Au and Pd. Due to the high cost of the shredding process and to avoid secondary pollution from odors and dusts, board scraps were cut into 5X5 cm2 pieces. To determine the most effective leachant, aqua regia, nitric acid, hydrochloric acid, ammonium persulfate and potassium persulfate were tested. The effect of the leaching parameters, the leachant concentration, temperature, leaching time and liquid to solid ratio were studied and optimized using response surface methodology.

Jan 1, 2011

By T. T. Campbell

A survey of the literature eras made covering the use of aqueous non-aqueous, and fused-welt systems for the electrowinning or electroplating of molybdenum metal. The survey was prepared in order to provide background for further investigations directed toward the electrodeposition of pure molybdenum metal from either aqueous or nonaqueous mediums. While a thorough effort was made to cover all available references, a critical review was not attempted nor does this survey pretend to be exhaustive in nature.

Jan 1, 1955

By D. Duvris

The main objective of this work was to quantitatively investigate exhaust emission levels, as related to maintenance (service) intervals, during the operation of diesel-powered equipment at an underground bauxite mine in Greece. Such emissions depend on a great number of parameters, including the type (technology) and tuning of the engine, the type of work performed as related to the engine workload, suggested maintenance intervals, the altitude, the temperature and the humidity of the atmosphere of the underground mine, the properties of the fuel, the operator's training and experience level. Necessary ventilation quantities were calculated based on exhaust gas concentration measurements, site specific relationships between pollutants and adjusted air quality indices. Diagrams comparing necessary and recommended air flow for several equipment groups featuring two engine types and for different maintenance intervals are presented.

Jan 1, 1998