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By S. L. Kher

The Singhbhum Copper Belt located in the state of Bihar in Eastern India bears evidence of ancient workings and indicates the existence of a civilized habitation in this region in the past. It was in 1833. how- ever, that the first official announcement of the occurrence of copper in the district was made. Although the occurrence was confirmed in 1847, it was not until 1857 that the first company was formed to exploit the deposits. This Company was dissolved in 1859 and from then until 1920, there were many unsuccessful attempts to develop and exploit the copper deposits in the Singhbhum area. In 1920. the Cordoba Copper Co. took an option on the Mosaboni area, which is nearly 10 km away from the present works located at Moubhandar, Ghatsila and exercising the option in 1924, purchased the mining rights from the Cape Copper Company. The Cordoba Copper Co. was then converted into Indian Copper Corporation Ltd. This was subsequently taken over by the Government of India in March 1972 and is now known as Indian Copper Complex (ICC), forming one of the two smelting units of Hindustan Copper Ltd.

Jan 1, 1976

By Jorge Alberto Soares Tenório, Denise Crocce Romano Espinosa, Kellie Provazi

"The purpose of this paper is to study metal separation and recovery from a sample composed of a mixture of the spent household batteries main types, using liquid-liquid extraction and metals electroplating. The electrolytes preparation consisted: grinding the waste of mixed batteries, reduction and volatile metals elimination using electric furnace and acid leaching. From this solution were studied the liquid-liquid extraction using Cyanex 272 [bis(2,4,4-trimethylpentyl) phosphoric acid] with tributyl phosphate as extracting agent. After study of solvent extraction and stripping has been recover and separate the metallic ions and with electroplating was recovered the manganese, copper, nickel and cobalt in their metallic forms.IntroductionCurrently has increased the consumption of electronics devices such as mobile phones, laptops, wireless phones, comcorders, etc., especially portable devices that use batteries as a power source, and consequently has increased the disposal of such material.Increased consumption of this devices is caused by several factors including increased popularity of consumer electronics devices, has become essential of modem life. Therefore, recycling of batteries is important because its reduces the waste of raw materias and nonrenewable resouces used in manufacturing these materias and help prevent potential environmental risks associated with improper disposal of these products together with household garbage.The batteries have a very diverse composition, containing metals such as zinc, lithium, nickel, lead, mercury, cobalt, cadmium, iron, copper, manganese and rare earths. Some components may contain hazardous materials such as cadmium, mercury and lead, and can contain acids or bases.This research line is a pioneer in dealing with a single process for recycling a mixture with all batteries types, for only processes that exist in the world are based on the recycling a mixture with all types of batteries, for only processes that exist in the world are based on the recycling of one or two types of batteries [1-4]. This process necessitates the previous separation of the batteries by type."

Jan 1, 2012

By Bror Nyrnan

Solvent extraction technology and equipment have been developed within Outokumpu since the early seventies. During this period altogether nine solvent extraction processes for molybdenium, zinc, rhenium, cobalt, nickel, calcium and magnesium have been commercially adopted in Outokumpu's metallurgical plants. During last years a new mixer-settler concept based on a "Vertical Smooth Flow" (VSF) principle has been developed. It has also been found to be a good method for copper solvent extraction, decreasing essentially the crud formation and the organic and aqueous entrainments.

Jan 1, 1994

By Marc Liebman

We present the results of a telephone survey of electric arc furnace (EAF) steel producers. This report characterizes the current status of EAF dust generation, treatment and disposal. It indicates the quantity generated, zinc content, other relevant constituents, and plans and trends that will impact on the quantity and characteristics of the dust generated. The survey covers EAF based steel producers in the United States and Canada. It identifies the processors currently employed, opinions about the use of these processors and services, as well as new technologies being considered.

Jan 1, 2000

By Andrew B. Suttie

The lead-acid battery recycling industry was seriously affected during the 1980s by increasing environmental protection costs and poor lead prices. The process is now being repeated in the 1990s causing further difficulties, for recyclers. In Europe, many lead-acid battery recycling plants use rotary furnaces. The Darley Dale smelter, redeveloped between 1984-87, uses only rotary furnaces. A review of options for this plant has been completed and 'concluded in favour of further investment to exploit more fully the benefits of rotary furnace technology.

Jan 1, 1995

By V. B. Telles, D. C. R. Espinosa, J. A. S. Tenório

"The purpose of this work was to study the reutilization of the steelmaking dust, derived from steel production in the electric arc furnace (EAF), in iron ore sintering process aiming zinc elimination. In each sintering process were collected sintered samples, these materials were analyzed by chemical analysis using atomic absorption spectrophotometry in order to determine the zinc content. Samples of not sintered mixtures were also characterized by chemical analysis aiming to determine the initial amounts of zinc, i.e. in order to check the zinc amounts present in the mixture before the sintering process. The comparation among the zinc contents of samples sintered and not sintered allowed to determine the elimination of zinc during the experiments. Results showed that the zinc elimination in the process is proportional to the ratio reducer/waste. The zinc removal was lower when the reducer/waste ratio was decreased.IntroductionThe electric arc furnace dust (EAFD) is a residue generated in the steelmaking process using electric arc furnace. Aproximately 30% of all steel produced (in the year 2009) was obtained through electric arc furance (EAF). In the United States of America the percentage of this process in the total crude steel production was about 62% in 2009, while in 2000 this percentage was only 47% [1].The iron ore sintering is a process that reuses wastes generated in metallurgical industries. However, the materials used must be physical and chemical characteristics compatible with the blast furnaces.The quantity of zinc, cadmium, chrome and other metals present in the EAFD depends on the quality of the scrap used to feed the EAF and the type of steel that it is been made [2,3]. The reuse of EAFD waste is interesting to steelmaking processes because of its iron content. However the presence of zinc inside a blast furnace is undesirable since the zinc oxide can be deposited on the blast furnace walls and in the drivers of gas output, interrupting the flow. Another part of the zinc oxide can form deposits on the refractory lining of the blast furnace [4,5]."

Jan 1, 2012

By Reza Rahimi, M. Nili Ahmadabadi

"Because of high cost and shortage of primary resources of Ni-base superalloys, revert alloys can be used as a part of charging materials for production of superalloys ingots. The current study is based on recycling of IN738LC, a Ni-base superalloy, using 30% and 50% reverted alloy and balanced amount of virgin raw materials. Therefore, it has been attempted to cast an alloy with references to standard chemical composition and mechanical properties. After charging and casting in vacuum melting furnaces, chemical composition verification and non-destructive tests (i.e. Penetration and Radiography Tests), quality of samples were evaluated at elevated temperature by stress-rupture test. Results acquired from chemical composition and mechanical test indicate that cast ingots using 30% and 50% reverted alloy is reliable and consistent with the quality control requirements.IntroductionIn recent years, there have been many fluctuations in cost and availability of raw materials which are extremely determining in Ni-base superalloys production. Accessibility to the high purity metals such as Cobalt, Molybdenum, Tantalum, Niobium and etc. have been problematical during the past decades. Therefore, shortages of critical raw materials beside the economical considerations motivated the alloy suppliers and investigators to study and find alternate sources such as reclamation and recycling of scraps [1].There are a lot of reasons for the necessity of recycling; perhaps the most justifiable one is that consumers themselves produce scraps. For example, the weight of a finished superalloy product could be less than one-third of the cast alloy weight and in the case of complicated machined parts; this portion may reach to one-tenth [2]. High values of constituents, reduction of energy consumption and environmental concerns have all strengthened the obligation of recycling in Ni-base superalloys.Because of the high degree of risk in usage of improper materials for production of turbine blades, a delicately controlled program for recycling is needed. Depending on the type of scraps, this program can define the recycling procedure, required instruments, allowable percentage of scrap for usage and finally confidence level of the process."

Jan 1, 2012

By Caisa Samuelsson, Taishi Matsushita, Hannes Holmgren, Sina Mostaghel

"Rönnskär Smelter of Boliden Mineral AB, Sweden, is a large end-processor of secondary raw materials and waste, including electronic scrap. Electronic scrap may introduce various impurities to the smelter's flow-sheet, among which alumina is a common and significant one. This article summarizes the results of an ongoing research at Luleä University of Technology, Sweden, to study the influences of alumina on different properties of slag from the zinc fuming process at Rönnskär smelter. A combination of different experimental techniques and thermodynamic calculations have been used to investigate properties such as density, surface tension, effective thermal diffusivity, viscosity, and melting/leaching behaviors. Results show that the addition of alumina to this slag increases the degree of polymerization of the melt, and physical properties vary correspondingly. Mineralogy of the semi-rapidly solidified samples is also changed due to alumina addition. A correlation between mineralogy and leaching behavior can be observed.IntroductionBoliden's Rönnskär Smelter is a base- and precious-metals producer located in north of Sweden. Its main products are copper, zinc clinker, lead, gold, and silver. Sulphuric acid, liquid sulphuric dioxide and iron sand (granulated slag) are some of its main by-products. In order to optimize the overall outcome of the process, different refining units are integrated in the smelter's flow-sheet (Figure 1). Copper concentrates and fluxing materials (mainly silica sand) are charged to the process. The produced matte is sent to the converter and the generated slag is charged to the fuming furnace, where it is treated by reducing gases to produce zinc clinker. The converter's slag is charged to the electric furnace, while the fumed slag is tapped into the settling furnace for further cleaning, where matte, slag and speiss (residual metals) are separated. The matte from the settling furnace is also sent to the converters; its speiss is sold to external customers; and its slag is water granulated and sold as construction material, which is known as iron sand."

Jan 1, 2012

By Sne?ana Devi

Mineralogy is a significant scientific discipline, essential in establishing the nature and the character of raw materials, regardless of whether they are monomineral or polymineral. Mineralogical characterization is very important, because its results give valuable information on features and nature of examined materials. Information's on mineralogical nature of mineral raw materials influence directly the quality assessment of a raw material, and thus the possibility of its use. The possibility of use of mineralogy in different industrial branches confirms constant activity of this scientific discipline. By use of methods within mineralogical analysis (optical microscopy, x-ray diffraction and others) data on mineral raw materials can be obtained as support in mineral raw materials quality assessment. Short description of results of mineralogical analysis of some mineral materials (granodiorite, dolomites, clay, refractory materials, slags and casting powders) in this paper shows the importance of its support to quality assessment and determine the possibilities of their use.

Jan 1, 2009

By John A. Mavrogenes

Reflected light microscopy and electron microprobe techniques were used to determine the mineralogy, phase percentages, grain sizes, and textures of Co-Ni-rich mattes. The mattes were produced by submerged bath smelting at the University of Missouri-Rolla Pyrometallurgical Center of a flotation concentrate with 4.S% Co and 5.1% Ni that was prepared at the United States Bureau of Mines Rolla Research Center by flotation up-grading of the cobalt and nickel content of a copper concentrate from the Magmont mine, Viburnum Trend, Southeast Missouri. Nine distinct phases were distinguished in the matte samples, and three of these contain cobalt and nickel. The phases that were free from cobalt and nickel are bornite, chalcocite, pyrrhotite, magnetite, metallic copper, and galena. Submerged bath smelting serves to segregate the cobalt and nickel into phases that can subsequently be recovered by flotation. These phases are: shandite (Ni3PbZSZ)' cobaltpentlandite ((Co,Ni,Fe)9SS)' and Co-bearing Fe-rich sphalerite ((Zn,Fe,Co)S). Most of the cobalt occurs in cobaltpentlandite, but some is present in sphalerite. High total air conditions during smelting favor the development and segregation of cobalt into cobaltpentlandite. Nickel occurs in cobaltpentlandite and shandite. Shandite contains lead, a deleterious constituent in the smelting of cobalt and nickel.

Jan 1, 1989

By Francis Vanbellen

Umicore Precious Metals Refining operates an integrated precious metals smelting and refining plant in Hoboken, Belgium. Once a smelter and refiner of complex concentrates, the plant today?s feed consists exclusively of industrial and consumer recycled products, making it the world?s largest recycling facility for precious metals. Unlike the fairy tale of the Frog Prince, it took much more than a princess? kiss to successfully realize this makeover. A completely renewed plant has been built over the past decade. The most visible technological innovation was the commissioning of the Pb-Cu smelter. Its flexibility towards very different types of feed makes it perfectly suited as main entry to the Hoboken flow sheet. A new Cu-leaching & electro winning plant and precious metals refinery make up the Precious Metals Operations (PMO) whose targets are fast throughput and maximized yields for gold, silver and the platinum group metals. The Base Metals Operations (BMO), flexibly process the by-products from the PMO, valorizing ?impurities? like indium, tellurium, selenium and others. Off gas and waste water treatments ensure compliance with strict environmental standards. Precious metals recycling is an art that goes beyond mastering a unique flow sheet. Umicore Precious Metals Refining offers a complete recycling service, taking care of sampling and assaying, metals management and logistics. The quality of this integral service is recognized through the attribution of ISO certifications for our operational activities, sampling and the environmental care. And it?s an art that follows Michelangelo?s experience: ?Art is 5% of inspiration and 95% of transpiration.?

Jan 1, 2006

By Francis Vanbellen

Umicore Precious Metals Refining operates an integrated precious metals smelting and refining plant in Hoboken, Belgium. Once a smelter and refiner of complex concentrates, the plant today?s feed consists exclusively of industrial and consumer recycled products, making it the world?s largest recycling facility for precious metals. Unlike the fairy tale of the Frog Prince, it took much more than a princess? kiss to successfully realize this makeover. A completely renewed plant has been built over the past decade. The most visible technological innovation was the commissioning of the Pb-Cu smelter. Its flexibility towards very different types of feed makes it perfectly suited as main entry to the Hoboken flow sheet. A new Cu-leaching & electro winning plant and precious metals refinery make up the Precious Metals Operations (PMO) whose targets are fast throughput and maximized yields for gold, silver and the platinum group metals. The Base Metals Operations (BMO), flexibly process the by-products from the PMO, valorizing ?impurities? like indium, tellurium, selenium and others. Off gas and waste water treatments ensure compliance with strict environmental standards. Precious metals recycling is an art that goes beyond mastering a unique flow sheet. Umicore Precious Metals Refining offers a complete recycling service, taking care of sampling and assaying, metals management and logistics. The quality of this integral service is recognized through the attribution of ISO certifications for our operational activities, sampling and the environmental care. And it?s an art that follows Michelangelo?s experience: ?Art is 5% of inspiration and 95% of transpiration.?

Jan 1, 2006

By Francis Vanbellen

Umicore Precious Metals Refining operates an integrated precious metals smelting and refining plant in Hoboken, Belgium. Once a smelter and refiner of complex concentrates, the plant today?s feed consists exclusively of industrial and consumer recycled products, making it the world?s largest recycling facility for precious metals. Unlike the fairy tale of the Frog Prince, it took much more than a princess? kiss to successfully realize this makeover. A completely renewed plant has been built over the past decade. The most visible technological innovation was the commissioning of the Pb-Cu smelter. Its flexibility towards very different types of feed makes it perfectly suited as main entry to the Hoboken flow sheet. A new Cu-leaching & electro winning plant and precious metals refinery make up the Precious Metals Operations (PMO) whose targets are fast throughput and maximized yields for gold, silver and the platinum group metals. The Base Metals Operations (BMO), flexibly process the by-products from the PMO, valorizing ?impurities? like indium, tellurium, selenium and others. Off gas and waste water treatments ensure compliance with strict environmental standards. Precious metals recycling is an art that goes beyond mastering a unique flow sheet. Umicore Precious Metals Refining offers a complete recycling service, taking care of sampling and assaying, metals management and logistics. The quality of this integral service is recognized through the attribution of ISO certifications for our operational activities, sampling and the environmental care. And it?s an art that follows Michelangelo?s experience: ?Art is 5% of inspiration and 95% of transpiration.?

Jan 1, 2006

By Peter G. Mason

Over the last 15 years numerous Pressure Oxidation and Pressure Leach plants have been installed throughout the world. The technology is no longer regarded with awe and trepidation as plants designed to treat a wide range of feedstocks continue to be successfully brought on line. Important aspects of the design of such plants include feed preparation, slurry pumping, heating and heat recovery, pressure control and let-down, vessel design, safety and provision of associated services.

Jan 1, 1999

By Fu-Shen Zhang, Mengjun Chen, Jianxin Zhu

"A novel approach for foam glass preparation, namely vacuum-aided powder sintering technique, was preliminarily investigated in the present communication. The key point of which was to prepare foam glass at a negative pressure. Compared to normal powder sintering process, the new approach could benefit the foaming process by shorting the holding time, reducing the amount of foaming agent and especially decreasing relative density of the product. Optimum conditions were 750 °C, 1000 Pa, 5 min and 1 wt.% foaming agent, respectively.IntroductionFoam glass represents a highly valuable solution for thermal and acoustic insulation, since it possesses a generally higher mechanical, chemical and thermal stability than other foams'1'. The first industrial processing for foam glass production, the direct introduction of gases (""blowing"") into the special molten glass, can be dated back to the end of 1930s'2'. At present, almost all foam glasses is prepared by powder sintering technique instead of blowing,3 since it reduces the temperature by several hundred degrees. Moreover, as fine glass powders or similar powders can be used to substitute corresponding glasses by this technique, considerable attention has been focused on the production of foam glass by considering fully recycled glasses, coal fly ash, or other solid wastes as raw materials,4 especially CRT glasses'3' 5', on the point of environmental protection.In a previous report'6', when discussing the lead removal and recovery from CRT funnel glass by a pyrovacuum process, we found that foam glass could be prepared at a negative pressure. Therefore, in this communication, the similarities and differences between the powder sintering process for foam glass at normal and negative pressure was preliminarily discussed."

Jan 1, 2011

By Honglei Zhang, Wuguo Xiang, Xinhao Huang, Guotao Xu, Xilai Chen

"The service behavior of refractories used in hot air pipeline for hot air stoves in a 3200 M3 blast furnace of WISCO was analyzed. The damage factors can be concluded as the poor quality of and alusite based bricks, the severe thermal shock damage, the more porosity in structures, loose bonding capability, and the unreasonable choice of materials and design of bricks. By analysis, the service life of hot air stoves can be enhanced by the measurements such as the reasonable choice of materials and their match, the use of light-weight refractories, the improvement of brick type, etc. Thereafter, the normal production operation of hot air stoves is guaranteed.IntroductionThe No.7 blast furnace of WISCO has been used for about 5 years and it was mid-repaired in March, 2012. The top phenomena of worn hot air pipelines are brick drop, breakage, severely local wear and deformation, existing hidden danger, so the worn hot air pipelines were renewed. Investigations have been done on the stove damage and design [1,2]. In order to clarify the wear mechanism, the used refractories for hot air pipelines were sampled and analyzed, the properties and structures of worn materials and reused materials are relatively studied."

Jan 1, 2013

By S. K. Utimurd, D. C. R. Espinosa, J. A. S. Tenório

"Waste Electrical and Electronic Equipment (WEEE) has become an environmental issue due to technological advance and waste plastic is one of the main polluters. The excessive discard of these plastics result in a difficult to dispose it to landfill and need further separation with technique in order to produce high added value plastics. There are many kinds of plastics in extensive use at the present time and the co=on are the acrylonitrile-butadiene-styrene (ABS) and high impact polystyrene (HIPS) used in the production of electric appliances. These plastics are difficult to separate because they have similar densities. Flotation of plastics is one possible separation technique and using selective wetting agents. The separation may be possible given close control at particle size and the concentration of the reagent. The process was able to produce a concentrate of HIPS with at least of 93% purity and a concentrate of ABS with 99% purity.IntroductionThe current situation of municipal solid waste (MSW) management especially in emerging economies like Brazil, the growing population and economic activity will result in a significant increase in the generation of waste in the coming decades. It is worthwhile to review and update the sources, amounts and recovery technologies of specific materials from waste, particularly from municipal solid waste (MSW).The growing impact of the current waste management practices stresses the need for a change in how waste is handled. The 2012 survey and the Brazilian Association of Public Cleaning and Special Waste Disposal Companies (ABRELPE) reports the generation of 62 Mt urban MSW in that year, which is an increase of 13% compared to 2011. It has been reported that in Brazil about 90.17% of the generated MSW is currently collected, which indicates an increase in the coverage of collection services compared to 2011 [ l]."

Jan 1, 2014

By Kenji Monden

"In order to obtain basic data for the development of highly thermally conductive composite materials, the thermal conductivity of a resin composite material with an Aluminum Nitride filler was assessed. Several different measurement techniques such as the xenon flash and the temperature wave thermometric analysis method were employed to gather data on these composites. An excellent match between theoretical and experimental data was achieved by employing a predictive expression that takes into account the effect of percolation on thermal conductivity.IntroductionA thermal solution composite is made by incorporating dense inorganic fillers with high thermal conductivity into a resin. Because the composite materials have high thermal conductivities, they have been used in electrical products that generate excessive thermal energy during operation, such as inverters, amplifiers and motor drivers. They function as electrically insulating and thermally conducting parts of the electric modules. As the uses of thermal solutions are expanded, composites of higher thermal conductivities will be required. The aim of this work was to investigate, evaluate, and try to predict the influence of key parameters on thermal conductivity and diffusivity. This was achieved by analyzing the effect of both volume fraction and shape of Aluminum Nitride ceramic fillers and measuring the thermal conductivity. In addition, the influence of percolation on thermal conductivity is considered. The thermal conductivity of the composites is discussed by employing a predictive equation using literature data of thermal conductivities for both the filler and resin. As well as thermal conductivity measurements the effect of volume fraction of the filler was also explored.ExperimentalSpecimen PreparationThe composite samples were prepared from silicone resin and Aluminum Nitride (AlN) fillers. The AlN fillers with an average particle size of 20 µm are shown in Figure 1. The mean diameters of the AlN particles used are given in Table I. For comparison the AlN fillers with an average particle size of 5 µm are shown in Figure 2. A planetary centrifugal mixer was used for simultaneously dispersing the components uniformly and de-aerating the mixture. After mixing, these materials were placed in a silicone rubber case and cured at 150 °C for 1 hour."

Jan 1, 2013

By Guanyong Shi, Zhihe Dou, Cong Wang, Ting'an Zhang, Hongyan Zhang

We prepared the CuCr alloy by thermit reduction-electromagnetic casting. But there are the defects such as stomata and oxide inclusions in CuCr alloy. In this paper, the existing state and distribution of inclusions and stomata in CuCr alloy are systematically analyzed. The alloy was characterized via SEM, EDS and metallographic microscope, in which the existing state and micro-structural defects of inclusions are analyzed. The results show that: there are three distinct areas: copper-rich areas, chromium-rich areas and the inclusion areas. Inclusions are mainly in the form of stomata and Al2O3 phase, mainly locating in the copper-rich phase and the interface area of chromium-rich phase and the copper-rich phase. Then, the composition of phases of the smelting slags and alloy were characterized via XRD. The results show that: the slag consists of Al2O3 and a little of Cr, the alloy consists of Cr, Cu and a little of Al2O3.

Jan 1, 2015

By Jian Li, Guo Chen, Bingguo Liu, Hongying Xia, Jinhui Peng, Libo Zhang

"Decomposition of ammonium tetramolybdate to prepare Mo03 using silicon carbide crucible in microwave fields was investigated. The results were analyzed Using TG-DTG and X-ray diffraction. Meanwhile, the effects of heating rat, material thickness, socking time, socking temperature on the structure of preparing Mo03 were studied. TG-DTG curves show that the decomposition process of ammonium tetramolybdate is only one stage, in the temperature range 300-350°C, whose begin to decompose when temperature increases beyond 300°C. The molybdenum trioxide was prepared by thermal decomposition. The quality ofMo03 was not affected under the heating rat is 12°C/min. It was beneficial for decomposition ratio with the lower material thickness, longer soaking time, and higher soaking temperature. XRD curves showed that it is viable method for preparation of Mo03 by decomposition from ammonium tetramolybdate in microwave fields.IntroductionMolybdenum is widely used in national defense, aviation, industrial and agricultural production as rare refractory metal. Molybdenum trioxide is vital raw materials for the process of preparation of molybdenum. The traditional production technology of molybdenum oxide is that ammonium tetramolybdate is calcined in rotary kiln or 4-tube furnace [J,2J. But the longer production time, the higher production cost, the lower furnace thermal efficiency, and bigger the energy consumption, especially the powder is easy to leak, the working environment is poor by using rotary kiln [ 3 l _ The particle of molybdenum oxide is non-uniform by using 4-tube furnace because of the uneven temperature of every tube and the poor exhaust of boat bottom [4l _ However microwave heating is quick and uniformity, it is a meaningful research that the microwave is used in the process of calcining ammonium tetramolybdate."

Jan 1, 2013