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By Kunio Nakahara, Kashiwagim Junichi, Takao Hayashi

"There are many problems for electronic devices and parts which were caused electrostatic damage by static electricity. It is necessary for prevention of electrostatic charge to decrease surface resistivity of material using electroconductive coating. Mitsui Mining & Smelting Co., Ltd. developed metal oxide type electroconductive pigment PASSTRAN (trade mark) Type-IV which is barium sulfate coated with SnOz(Sb) thin electroconductive layer. This paper shows about pigment characteristics and film condition of antistatic transparency paint which contained PASS TRAN.L.IntroductionRecently rapid development of electronics technology diffused electronic devices and products to Office, Factory, Laboratory and our life. But the other side, there are many problems for electronics parts which were caused electrostatic damage under static electricity. Demand of antistatic materials were become lager by this situation.There is close relationship between surface resistivity of material and static electricity. If the surface resistivity of object is enough low (under 109 Q /Sq), static electricity is dissipated quickly. So it is necessary for prevention of electrostatic charge to decrease surface resistivity of material using electroconductive coating.1) There are many type of electroconductive materials, for example, carbon black, metal powder, electroconductive polymer and so on. Especially, carbon black is used for general purpose by reason of its low cost, but it has big problem of black color. It can not get any color without black, and it caused contamination of carbon.In recent years, metal oxide electroconductive pigment (ECP) was developed and used for special purpose which demands transparent coating or easy dispersion to make ECP paint or endurance under hard environment and so on. Mitsui Mining & Smelting Co., Ltd. developed electroconductive pigment PASSTRAN Type-IV which is BaS04 coated with electro-conductive Tin oxide layer."

Jan 1, 1998

By Guo Chen, Jin Chen, Jinhui Peng

In this paper, solving common problem of electrostatic precipitator (ESP), which was frequently ruptured of the cathode insulation in the production process were studied. The microwave heating airflow technology was introduced, which takes full advantage of its unique properties, solves the output problem of the high temperature air, achieves purpose of energy conservation, important economic significance and environmental significance. The mathematical models and designing of microwave high-temperature hot air system was calculated. The common forms of heat exchangers and comparative analysis were also introduced. The conditions found to be at the temperature of 240 °C. Under optimum conditions, the microwave heating power was 1482 W. Based on the mention results, this microwave heating method can be applied effectively and efficiently way for the production process of electrostatic precipitator.

Jan 1, 2015

By J. -C. Tedenac, C. Colinet, X. Tao, P. Jund, R. Viennois

"We report an ab-initio study of the stability and electronic properties of transition metal silicides in order to study their potential for high temperature thermoelectric applications. We focus on the family M5Si3 (M = Ta, W) which is stable up to about 2000 °C. We first investigate the structural stability of the two compounds and then determine the thermopower of the equilibrium structure using the electronic density of states and Mott’s law. We find that W5Si3 has a relatively large thermopower but probably not sufficient enough for thermoelectric applications.IntroductionIn the search of new sustainable energies, thermogeneration of electricity is one of the promising ways, notably because it is able to produce electricity from different kinds of heat wastes and to its portability. However, despite recent progress in the field, the state-of-the art materials have specificities making their mass-production difficult or even impossible: toxicity (thallium, chalcogen or/and pnictogen based alloys), weak abundance (tellurium based alloys) or cost (germanium or rare-earth based alloys). For all these reasons, finding thermoelectric materials without these drawbacks is vital if we wish to use high temperature thermoelectricity for generating electricity in the near future. Due to their abundance, low cost and low toxicity, transition metal silicides are candidate materials of primary interest and the slightest advance in this field would immediately find an application for the thermogeneration of electricity."

Jan 1, 2011

By Dong Hoon Han

The simultaneous sulfation by sulhr dioxide and oxygen of CaO and MgO in calcined CMA (calcium magnesium acetate) were investigated. he experiments were carried out in the temperature range from 700 to 830 "C and at the SO2 concentrations of 0.3 to 1 mol %. The oxygen concentration was kept at 5 %. Each sample was calcined completely before the temperature was lowered to the sulfation temperature. According to the ranges of partial pressure of sulhr dioxide and temperature, there exist three regions for the sulfation reaction: region I in which neither oxide is sulfated, region I1 in which only CaO is sulfated, and region 111 in which both oxides are sulfated. It was shown that the MgO in calcined CMA is sulfated at a rate comparable to that of CaO by forming a mixed sulfate phase. Thus, unlike MgO contained in other desulhrization materials, the MgO content in calcined CMA can be fully utilized for flue gas desulhrization.

Jan 1, 1999

By Xiancong Zhao, Hao Bai, Qi Shi, Zhancheng Guo

Reducing electricity cost is important for energy intensive industries such as the iron and steel industry. With the implementation of time-of-use (TOU) electricity price, plenty of attention has been paid to the optimal management of byproduct gases. The time-of-use (TOU) electricity price is the practice of implementing different prices for different times of use. It is possible to reduce electricity cost by adjusting the amount of product gases stored or used for power generation throughout the day. In this paper, a novel mixed integer linear programming (MILP) model concerning the TOU electricity price is proposed to optimize byproduct gas use. Compared with previous models, this model considers the optimal load shift between gasholders and boilers under TOU electricity price. The case study of a steel plant demonstrates that the electricity purchase cost can be reduced by more than 30% after optimization.

Jan 1, 2016

By Mao Chen, Baojun Zhao, Zhixiang Cui

Bottom blown oxygen copper smelting process, operated at high grade matte (up to 75 wt% Cu) with relatively low (2-3 wt%) Cu in slag, has been commercialized for more than five years at Dongying Fangyuan Nonferrous Metals CO., Ltd. Quenched slag and matte samples have been collected at different operating conditions while the slag temperature was measured by thermocouple. The samples were analysed by X-ray Fluorescence and Electron Probe X-ray Microanalysis. FactSage computational software was used to explain the observations of the industrial samples. The analyses show that the copper loss was closely related to the operation parameters. The Fe/SiO2 in slag and temperature determine the solid proportion, which significantly affects the physical entrained and also chemically dissolved copper in the slag. The present study will be useful in understanding the slag chemistry of bottom blown copper smelting furnace and in optimization of the operating conditions to lower Cu loss in the slag.

Jan 1, 2015

By June-Yong Eom, Jong-Jin Pak, Jung-Mock Jang, Min-Kyu Paek

The nitrogen solubility in liquid Mn-Si, Mn-Si-Fe, Mn-Si-C and Mn-Si-Fe-C alloys has been measured by the gas-liquid metal equilibration technique in the temperature range of 1673-1773 K. The additions of silicon, iron and carbon significantly decreased the nitrogen solubility in liquid manganese alloys. The experimental results were thermodynamically analyzed by the Wagner’s formalism to determine the first- and second-order interaction parameters of silicon, iron and carbon on nitrogen in liquid manganese. The thermodynamic parameters can be used to predict the nitrogen solubility in ferromanganese and silicomanganese alloy melts as functions of the melt composition and temperature at given nitrogen partial pressures.

Jan 1, 2014

By Y. Waseda, S. V. Gnyloskurenko

"Present paper reviews the various processes for making of metallic foams. These methods are classified in accordance with the state of initial metals - liquid, powdered and ionized. Liquid metal can be foamed by direct inputting of gas into melt, using gas releasing foaming agents or producing supersaturated metal-gas solutions. This group also includes methods creating voids in the melt. Powder route is based on using powdered matrix metal with foamable precursor materials. Finally Deposition techniques allows making highly porous metallic structures using ionized metal.Experimental study presented shows importance of wettability in bubble formation at gas blowing into melt simulation liquid (water) through holes. Good wettability of injection holes by water ensures formation of bubbles with smaller sizes that effect to the final foam structure.IntroductionOne of the objectives of future production technology is to make of lightweight constructional materials while achieving improved property and good economy as well.The most perspective lightweight materials are cellular or foamed materials that are Wide8pread. in nature and have a growing interest in industry and everyday life.Even metals and metallic alloys can be produced as cellular solids or metal foams beside of the traditional engineering materials such as polymers, ceramics or glass. Recent developments in metal foams, especially aluminium, have produced a new class of lightweight materials."

Jan 1, 2000

By N. M. S. Balbinot, A. L. Rodríguez, C. M. Mahlmann, R. de C. de S. Schneider

The use of sunflower oil co-products it was studied for production thermoplastic composites. Thermoplastic composites have been processed in polyethylene matrices of virgin linear low density polyethylene (LLDP) or recycled. Samples have been formulated with 10% mass fraction of sunflower bran, seed coat and mixture of bran and seed coat. The material characterization has been achieved by mechanical tensile test and Shore D hardness and by density physical testing. The results have demonstrated better properties to thermoplastic composites with sunflower seed coat.

Jan 1, 2008

By Robert B. Haagensen

While light optical microscopy has long been employed by the mineral processing industry, there has been a tendency to shy away from its use for all but the most exacting purposes. Despite the usefulness of micros-copy in solving a wide variety of problems, the response to such work is often less than enthusiastic primarily due to time considerations. Microscopical techniques are therefore often relegated to the "ivory tower" and their direct and practical application to everyday problem solving over-looked. The purpose of this paper is to dispel such attitudes and promote a wider use of light microscopy. Several examples are given which point out the indispensib1e nature of optical microscopy as a rapid means of defining and solving problems in mineral processing. The application of other instrumental techniques to augment the information obtained is also discussed, particularly the value of the combined use of the optical microscope and electron probe micro-analyzer.

Jan 1, 1981

By Zhiqian Zhang, Chao Wu, Chao Li, Hongxu Li, Yu Chen, Xiangxin Hao

"In this paper, the life cycle assessment models for automobile lightweight materials including high-strength steel, aluminum alloy and magnesium alloy are developed by Gabi software. The evaluation models and evaluation indicators such as acidification effects, rich eutrophication effect, ozone layer depletion effects, global warming, resource consumption and formation of ozone potential were taken into account. It is shown that the effects of acidification and ozone formation are mainly derived from the run phase of high-strength steel and they have strong environmental impact load. While considering the entire life cycle with materials production phase and resource consumption, the aluminum and magnesium alloy appe art o have large r environmental load than high-strength steel. Base d on the evaluation, some optimization tips are proposed.IntroductionAs the increasing of car ownership, automobile has its two sides. One which is the convenient, efficient and fast traffic vehicle; the other is aggravating energy consumption, emissions and environmental pollution. The car industry faces heavy pressure with energy saving, safety and environmental protection. Nowadays, the main study ways for automotive energy-saving and environmental protection are power system improvement, alternative energy sources and technologies. For limitation of technique, development cycle and market share, the development of car is little progress at this stage and the application has been restricted. And another important way is the lightweight of vehicle. Usually there are three ways to get the lightweight automobile body structure, automobile body structure optimized design, using advanced body manufacturing technology, development and application of lightweight high strength body material.The life cycle assessment (LCA)[1lis commonly used to evaluate environmental factors and potential environmental impacts of products and services. As an environmental management tool of product-oriented, it becomes increasingly popular in industry. In this study, the concept of LCA and GaBi software was used to develop models for the three automotive lightweight materials, evaluate the environmental impact and make horizontal and vertical contrast by choosing variety of evaluation systems and indexes."

Jan 1, 2013

By Yoshimasa Oda

The tank house of Tamano Smelter has adopted a high current density electrolysis operation applying PRC (Periodic Reverse Current) method and before 1991, it had materialized both high production capacity of 161,000 tons/year and high labor productivity. However, recent rapid rise of Japanese currency in foreign exchange market has urged us to further exert our efforts in reduction of labor cost. In order to achieve this goal of labor cost reduction, we have completed, in 1994, our phase four production expansion project which incorporated significant re-structuring of the organization and we have accomplished annual production of 191,000 tons/year. This project can be outlined as increase of number of cells for electrode exchange per day in the commercial electrolysis process to meet the increased number of cells and increase of the capacity of impurity treatment process. These improvements were done with minimum installation of new equipment and facilities and with achievements in efficiency and manpower saving of the existing facilities. Together with these improvements, rationalization in the starting sheet section was carried out by changing the material of mother blanks as well as changing their maintenance procedures. At the same time, the crane in this section was modified to enable automatic operation by a fuzzy control. As a result, we were able to save manpower equivalent to 5 operators in this section. With these improvements, the production capacity was increased by 18% and labor productivity by 25%.

Jan 1, 1996

By Zhang Chuanfu

The fibrous nickel oxide powder was prepared by the method of chemical precipitation and pyrolysis, that is, the NiO precursor was firstly precipitated from nickel ions solution with addition of oxalate salt and then the final NiO powder was obtained by pyrolysis of the prucursor. The effects of the pH, reaction temperature, reactant concentration, addition of surfactant on the morphology of the precursor particles were investigated. The influences of the various conditions, including the temperature and time, the air flow and the speed of the temperature increase on the morphology, average size and specific surface area of the NiO particles were also addressed. The fibrous NiO particles with IOO~ 120 in axis/diameter ratio and 5.5 m2/g of the specific surface area may be produced under certain operation conditions by this process.

Jan 1, 2003

By Yuan Lu, Yiming Rong, Richard D. Sisson Jr

With the development of quench technology, there is a trend of using gas quench to replace liquid quench for less distortion and residual stress. The fundamental difference between the liquid and gas quench is the heat transfer coefficient, not only the values but also the shape of the curve as a function of temperature. The equivalent heat transfer coefficient for the liquid and gas quench is analyzed by simulations and experiments. Even it may result in the same hardness in the liquid and gas quench, the steel microstructure may be different because of the different cooling processes, and therefore other steel properties, such as toughness, may be different. The cooling process, microstructures and properties such as hardness and toughness should be examined when designing the liquid or gas quench processes.

Jan 1, 2015

By Nobuhiro Ishikawa

The in-situ observation of the effect of impurities on the reduction process of iron oxides by C in TEM was carried out. A few wt% of CaO or AbO, was used as impurities in FeO was prepared. Some precipitates grew into the C layer expect for using 3.0wtCa. The reaction between FeO and carbon was much different from using pure FeO at about 800-1 lOOK. The rate of reaction became much slower including Ca and almost no reaction was happened with the concentration of CaO up to 3.0wt%. On the contrary, AbO, had ahuost no effect on the reaction. The results indicated that Ca suppressed the reaction and the effect of Al was much less. The precipitates which grew into C layer accompanied almost no Ca and AI. Only Fe was detected in the precipitates.

Jan 1, 2008

By T. Ranki-Kilpinen

In the flash smelting technique, developed by Outokumpu Oyj, off-gases with dust load are directed into the heat recovery boiler (HRB). As the temperature decreases, metallic sulphates become thermodynamically stable. Sulphation of oxidic particles initiates. The release of heat causes an increase in particle temperatures, and soft sulphated particles can stick to the heat transfer surfaces. Dust accretion may form and cause operational problems. The objectives of the project are to study sulphation reaction mechanisms and kinetics of flue- dust particles under HRB conditions, and get more information for the flue-dust treatment possibilities. The sulphation behaviour of synthetic Cu2O particles (37-53 pm) was studied using a fluid-bed reactor of laboratory scale. The experimental parameters in the latest campaign were oxygen and sulphur dioxide contents of 2.5-10 vol-% 02 and 40-60 vol-% SO2 respectively and temperatures of 600-660°C. Samples were examined microscopically (SEM+EDS) and chemical analysis were conducted. The sulphation rate was found to have a maximum at the certain temperature, which was dependent on the gas SO2 content. Regardless of the level of SO2, a rise in oxygen content promoted sulphate formation.

Jan 1, 2002

By Tong Deng

Clean processing of copper converter slags for reclaiming cobalt and copper could be a challenge. An innovative and environmentally benign approach for recovering metal values from such a slag was developed in the present work. Curing the slag with sulfuric acid, without re-smelting or roasting as currently practiced in the industry, made it amenable to leaching, and more than 95% of the cobalt and up to 90% of the copper was extracted, together with iron, by water leaching, leaving silica behind in a residue. Copper in the leach liquor was recovered by cementation with iron, and the dissolved iron crystallized as ferrous sulfate monohydrate. Cobalt in the pregnant solution rich in iron was recovered by either cementation or sulfide precipitation. Chemical and mineralogical characterization of the slag and its products were examined and compared to determine the nature of the changes occurring during curing and leaching. Operating variables were also investigated and optimized.

Jan 1, 2003

By Luis W. Pommier

The wastes of the plating industry are generated in the process of rinsing the plated objects and during the cleaning of the plating shops. High volumes of hazardous waters are neutralized on site producing recyclable water, generating a metal rich, hazardous, filter cake. Occasionally, a complete plating bath has to be discarded which increases the metal content of the filter cakes. These filter cakes are discarded as hazardous at a cost of over $ 250 per ton. The metals found in the cakes are generally copper, nickel and chromium or zinc, lead and cadmium, assaying from 2% to 15% or even higher content of each metal The metals and their contents are highly variable. Some plating shops discard their products directly to hazardous waste sites, others, have them collected by companies which consolidate wastes from several producers prior to discarding. These wastes, richer in metal content than mine ores, need neither mining nor crushing and grinding for concentration. The commonly found impurities in the mine ores, i.e.: pyrites, arsenic, and valuable metals which are present in minute quantities, are absent in the filter cakes. The processes available to selectively recover the metals from the filter cakes, are discussed based on their technical and economic merits. The flow-sheets include leaching, solvent extraction when required, and electrolytic refining. Examples, showing the separation of copper, nickel and chromium and also of zinc and lead in pilot plants, show the technical and economic viability of the processes.

Jan 1, 1996

By Esher Hsu

On July 5, 1997, Environmental Protection Administration of Taiwan publicized the recycling regulation of waste home appliances that include four items, namely, television, refrigerator, washing machine, and air conditioner. It is believed that this regulation pioneers the law enforcement of waste home appliances in the world. The objective of this study is to provide helpful base for amending recycling rates of waste home appliances. This study investigates the collection and recycling costs of waste home appliances in accordance with these newly established routes and facilities, respectively. Cost survey was conducted among collectors and recycling plants of waste home appliances; consequently, the collection and recycling costs were analyzed, correspondingly. Results provide some suggestions regarding recycling route, recycling system, recycling rates paid by manufactures and importers, recycling subsidies to collectors and recyclers. Those suggestions may provide useful policy implications to EPA for the future decision-making regarding the recycling of waste home appliances.

Jan 1, 2003

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