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By Vittorio Basilico, Marco Quattrone, Mario Bassan

"In Italian building market one of the reasons that often stop building contractors from not taking into consideration the possibility to recycle rubble from building is represented by the increase of costs for rubble separation. However the recycling of C&DW can also allow a decrease in disposal costs and a reduction in raw materials requirement.In this paper the results of a testing conducted on a case study through economic and technical analyses are presented.Results highlight that a wise management of demolition and disposal processes can generate a remarkable saving and that it is possible, on the other side, to achieve environmental benefits such as reduction of raw material consumption and dump life lengthening.IntroductionTwo major factors have been found to have considerably influenced the market of recycled aggregates in Europe and Italy: the EU and national regulations and environmental awareness. The market of recycled aggregate has grown in countries with limited natural resources.Waste disposal has also been one of the top EU political and environmental priorities. In the complex interaction between human activities and the environment, waste is proved to be one of the most environment-degrading products.In 1972 the European Commission introduced measures on waste reduction, reuse and recycling. In 2006, directive 2006/12/EC (European Commission) on waste was issued. It covers the scope of minimizing the waste, prevent hazardous waste, maximize reclamation, reuse, recycling and energy-recovery.No specific directive refers to management and recycling of construction and demolition wastes. However, in 1992 the European Commission listed debris among waste management priorities because of its growing amount.Only recently, effective environmental policies have been implemented in Italy, even though relevant environmental issues started rising as early as the beginning of the 1970s. In the 1980s the Government undertook the first significant measures to handle the waste management."

Jan 1, 2008

By Emilia Visileanu, Eftalea Carpus

"Ecological economic policy shall be understood as the sum of political, economical and environmental measurements aimed at the entire economy dematerialization and the dematerialization shall be ""imposed"" since the designing stage of goods and services"". European textile and clothing industry with a long leading tradition in terms of innovation, fashion and creativity, continues to be one of Europe's major industrial sectors. Textile industry affects the environment by high consumption of water, energy and chemicals, as well as by the large amount of waste it generates as a result of using a large number of chemicals and technological processes.Textile waste prevention, reduction and ecological exploitation require the implementation of new management and education tools.Introduction“Europe must learn from the experience of global economic and financial crisis ""- this was the conclusion of the European Commission that has elaborated a ten-year strategy designed to reinvigorate the economy and make possible a growth which is ""intelligent, sustainable and favorable to inclusion"", by a better coordination of national and European policies.Adapting infrastructure and logistics that encourage the marketing of ""sustainable"", ""fair traded"" and ""green"" products as well as other special „green” products will facilitate the movement towards dematerialization and eco-efficiency among producers."

Jan 1, 2012

By Pinakin C. Chaubal

Today?s steel industry is in a vibrant and resurgent mode. This transformation has been in the making for some time now. Over the last few decades, the industry was steadily transforming itself into becoming a high tech industry. New technology was adopted, efficiencies were enhanced, lean manufacturing concepts were brought in and a strong customer focus was developed. Today?s mills employ sophisticated instrumentation, computerized monitoring, on-line smart systems etc. driving processes that are producing at rates of many tons/minute. All this is not possible without judiciously using the latest available technologies in various fields and developing a more sophisticated work force. Prof. Sohn has been a pioneer in driving the concept of process engineering in process metallurgy. In this paper the focus is on some aspects of process engineering ? primarily process modeling - as applied to iron and steelmaking processes. Examples are shown to demonstrate how problems have been addressed. Some thoughts on future directions are presented.

Jan 1, 2006

By Pinakin C. Chaubal

Today?s steel industry is in a vibrant and resurgent mode. This transformation has been in the making for some time now. Over the last few decades, the industry was steadily transforming itself into becoming a high tech industry. New technology was adopted, efficiencies were enhanced, lean manufacturing concepts were brought in and a strong customer focus was developed. Today?s mills employ sophisticated instrumentation, computerized monitoring, on-line smart systems etc. driving processes that are producing at rates of many tons/minute. All this is not possible without judiciously using the latest available technologies in various fields and developing a more sophisticated work force. Prof. Sohn has been a pioneer in driving the concept of process engineering in process metallurgy. In this paper the focus is on some aspects of process engineering ? primarily process modeling - as applied to iron and steelmaking processes. Examples are shown to demonstrate how problems have been addressed. Some thoughts on future directions are presented.

Jan 1, 2006

By Pinakin C. Chaubal

Today?s steel industry is in a vibrant and resurgent mode. This transformation has been in the making for some time now. Over the last few decades, the industry was steadily transforming itself into becoming a high tech industry. New technology was adopted, efficiencies were enhanced, lean manufacturing concepts were brought in and a strong customer focus was developed. Today?s mills employ sophisticated instrumentation, computerized monitoring, on-line smart systems etc. driving processes that are producing at rates of many tons/minute. All this is not possible without judiciously using the latest available technologies in various fields and developing a more sophisticated work force. Prof. Sohn has been a pioneer in driving the concept of process engineering in process metallurgy. In this paper the focus is on some aspects of process engineering ? primarily process modeling - as applied to iron and steelmaking processes. Examples are shown to demonstrate how problems have been addressed. Some thoughts on future directions are presented.

Jan 1, 2006

By Pinakin C. Chaubal

Today?s steel industry is in a vibrant and resurgent mode. This transformation has been in the making for some time now. Over the last few decades, the industry was steadily transforming itself into becoming a high tech industry. New technology was adopted, efficiencies were enhanced, lean manufacturing concepts were brought in and a strong customer focus was developed. Today?s mills employ sophisticated instrumentation, computerized monitoring, on-line smart systems etc. driving processes that are producing at rates of many tons/minute. All this is not possible without judiciously using the latest available technologies in various fields and developing a more sophisticated work force. Prof. Sohn has been a pioneer in driving the concept of process engineering in process metallurgy. In this paper the focus is on some aspects of process engineering ? primarily process modeling - as applied to iron and steelmaking processes. Examples are shown to demonstrate how problems have been addressed. Some thoughts on future directions are presented.

Jan 1, 2006

By Pinakin C. Chaubal

Today?s steel industry is in a vibrant and resurgent mode. This transformation has been in the making for some time now. Over the last few decades, the industry was steadily transforming itself into becoming a high tech industry. New technology was adopted, efficiencies were enhanced, lean manufacturing concepts were brought in and a strong customer focus was developed. Today?s mills employ sophisticated instrumentation, computerized monitoring, on-line smart systems etc. driving processes that are producing at rates of many tons/minute. All this is not possible without judiciously using the latest available technologies in various fields and developing a more sophisticated work force. Prof. Sohn has been a pioneer in driving the concept of process engineering in process metallurgy. In this paper the focus is on some aspects of process engineering ? primarily process modeling - as applied to iron and steelmaking processes. Examples are shown to demonstrate how problems have been addressed. Some thoughts on future directions are presented.

Jan 1, 2006

By Pinakin C. Chaubal

Today?s steel industry is in a vibrant and resurgent mode. This transformation has been in the making for some time now. Over the last few decades, the industry was steadily transforming itself into becoming a high tech industry. New technology was adopted, efficiencies were enhanced, lean manufacturing concepts were brought in and a strong customer focus was developed. Today?s mills employ sophisticated instrumentation, computerized monitoring, on-line smart systems etc. driving processes that are producing at rates of many tons/minute. All this is not possible without judiciously using the latest available technologies in various fields and developing a more sophisticated work force. Prof. Sohn has been a pioneer in driving the concept of process engineering in process metallurgy. In this paper the focus is on some aspects of process engineering ? primarily process modeling - as applied to iron and steelmaking processes. Examples are shown to demonstrate how problems have been addressed. Some thoughts on future directions are presented.

Jan 1, 2006

By Pinakin C. Chaubal

Today?s steel industry is in a vibrant and resurgent mode. This transformation has been in the making for some time now. Over the last few decades, the industry was steadily transforming itself into becoming a high tech industry. New technology was adopted, efficiencies were enhanced, lean manufacturing concepts were brought in and a strong customer focus was developed. Today?s mills employ sophisticated instrumentation, computerized monitoring, on-line smart systems etc. driving processes that are producing at rates of many tons/minute. All this is not possible without judiciously using the latest available technologies in various fields and developing a more sophisticated work force. Prof. Sohn has been a pioneer in driving the concept of process engineering in process metallurgy. In this paper the focus is on some aspects of process engineering ? primarily process modeling - as applied to iron and steelmaking processes. Examples are shown to demonstrate how problems have been addressed. Some thoughts on future directions are presented.

Jan 1, 2006

By Suk J. Im, I. S. Min, Daesoo Kim

UFP are defined by atoms or their clusters having diameter in the range of l0Å-0.l.um. Due to a ratio of very large surface area to volume, they have peculiar properties such as extra high surface energy. Recently UFP deposition technique may find its new applications to various areas such as conductive/resistive film formation. In this method, gas flow with UFP jet through the nozzle which is considered to be a free molecular flow is maintained at a very high speed (~100m/s). Using this technique, mixture film of Fe and Ni, and Ag/ Ag-Alloy etc. were obtained, and their mechanical and electro-magnetic properties were determined. The experimental results are pending. The test results and discussion will be presented in the main paper.

Jan 1, 1988

By Yuan Zeping

This paper describes the distribution and removal of the main impurities in the pyrometallurgical process ?at the Guixi Smelter. The paper discusses in detail our converting schedule?of3S-SB and injecting deeply a mixture ofNa2CO) and CaO flux into the converters to enhance impurity removal.

Jan 1, 1998

By D. D. Harbuck

The U.S. Bureau of Mines recently identified a significant new source of scandium in an Oklahoma tantalum waste residue (approximately 0.24 pct Sc). Because scandium is a strategic and critical metal which the Department of Defense has classified for special consideration, the Bureau is researching methods of recovering scandium and associated metals from this and other process residues. A variety of operating parameters were evaluated to determine the best technique for recovering scandium. Testing showed that by sulfating the residue at temperatures as low as 150' C for reaction times as short as 0.5 hr, over 94 pct of the scandium converted to a water soluble form. Solvent extraction using DEHPA selectively recovered 100 pct of the scandium from the water leach solution.

Jan 1, 1992

By C. Lupi

The electrorefining of primary copper is a well known technology: in this work copper scrap was directly processed in the same way. he copper and copper alloy scrap was previously pressed by means of a 20 tons apparatus in order to avoid pyrometallurgical operations. The samples obtained in this manner showed a good compactness so that they were used as anodes in the electrorefining tests. The tests were carried out on anodes made by copper scrap, copper alloy scrap and a mixture of the two. The electrorefining tests were performed at both 303 and 333 K, in a perspex cell having a volume of 500 ml using a current density of 250 A/m2. The cathode used was always a sheet of pure copper and the electrolyte composition was 40-50 g/l Cu as CuS04 and 150-200 g/l H2SO4. Current efficiency in the range of 92-97% and specific energy consumption ranging from 0.14- 0.20 kWg of copper were reached in all the tests. The refined copper deposits were analyzed by AAS to verify their purity and observed by SEM to highlight their morphology.

Jan 1, 1998

By T. Kozuka, K. Sassa, S. Asai

"A new atomization process is developed. The principle of this process is completely different from that of conventional processes. This process uses electromagnetic energy induced by direct electric current and direct magnetic field instead of kinetic energy produced by fluid impingement or disk rotation.Experimental work of this process was carried out using pure tin, and it was found that the crucial factor for a stable operation is the contact state of molten metal with the electrode. In order to control the condition, a delay time controlling unit was developed and combined with this process. It is noticed that this controller works well to produce uniformly sized particles.A linear relation between the impulse and the momentum of atomized particles is found by use of experimental data and is explained by theoretical analysis.IntroductionIn atomization processes prevailing in metal powder technology, kinetic energy is currently employed for atomizing molten metal. That is, molten metal is broken into small particles by other fluid (e.g. water, argon gas, etc) or by impinged upon a rotating solid disk. This splashing process is always accompanied with uncertain factors for shape and size of the particles. The diameter distribution of products, therefore, comparatively spreads over a wide range. From another standpoint, the restriction of atmosphere is inevitable in some of these processes. As a pulverizing technology, the process which can produce uniformly sized particles and permits the choice of atmosphere is strongly desired.On the other hand, a great attention has been paid to the spray casting process as a new near net shape casting. In this process, a small size spraying device is favorable."

Jan 1, 1988

By Masatsugu Morimitsu, Tian Zhang

"This paper presents a novel anode for oxygen evolution in acidic aqueous solutions to produce non-ferrous metals by electrowinning. The method to prepare the anode was thermal decomposition of a precursor solution, and the obtained anode consisted of Ru02-based oxide catalytic layers formed on a titanium substrate, in which the catalytic layer contains nano-oxide particles as the active component. The oxygen evolution potential was lower than amorphous lr02-Ta20s coated titanium anodes so that the cell voltage of electrowinning was further reduced with the amorphous Ru02-based electrode.IntroductionElectrowinning (EW) is used to produce high purity of non-ferrous metals, and the primary metal production of copper, zinc, nickel, and cobalt by EW consumes huge electric energy worldwide, which tends to increase with increasing demand of such metals. The reduction of electric energy consumption is a significant issue for electrowinning industry, which means that the cell voltage reduction is needed to realize more energy-efficient EW processes. Another issue is also indicated from environmental perspectives; i.e., an improvement in EW plant environment by eliminating hazardous byproducts and wastes. Such byproducts and wastes include lead oxide, manganese oxide, and acid mist.We have been developing the anodes for energy-efficient and environmentally friendly electrowinning processes [ 1-11]. The development has been successfully done with the invention of the smart anode, MSA TM (Morimitsu Smart Anode) [ 1-5], which has low polarization for the main reaction and high polarization for the side reaction, in which the main reaction is oxygen or chlorine evolution, while the side reaction is the anodic deposition of each or both of lead oxide, manganese oxide, and cobalt oxide. The anode consists of a valve metal substrate coated with amorphous or less crystalline oxide catalytic layers. One of the typical examples of such oxides is amorphous lr02-Ta20s, and the substrate is normally titanium plate or mesh. The most important point of the oxide is that the amorphization or less crystallinity induce the increase in the active surface area only to the main reaction, not to the side reaction, thereby the polarization of the main reaction being reduced.In this paper, we present the smart anode consisting of RuO2-based catalyst formed on titanium substrates for oxygen evolution in electrowinning. The preparation, characterization, and polarization behaviors of the anodes are shown, and the cell voltage data for zinc or copper electrowinning using the anodes are also presented."

Jan 1, 2012

By Joseph C. Milbourne

The selection of a suitable nitrate removal process depends on a variety of site-specific chemical and environmental issues. The dominant technologies for nitrate removal include biological denitrification and continuous countercurrent ion exchange. The decision to apply either of these technologies, or both together, depends on the nature of the waste water to be treated. Factors that affect the selection of the biological system include the feed composition and feed temperature. Ion exchange nitrate removal systems are less sensitive to the feed composition but require disposal or destruction of the concentrated pregnant eluate. The paper discusses Tetra's continuous countercurrent ion exchange technology (CCIXTM) and fixed film biological reactor, Denite°. The treatment of the ion exchange pregnant eluant is also discussed.

Jan 1, 1994

By Guo Xueyi

The dissolution behaviors of valuable metals, lead and zinc, from secondary fly ash generated in municipal incineration plants were investigated using some lixiviants: sulfuric and hydrochloric acids, acetic acid and some chelating reagents including L-asparaginic-N,N-diacetic acid (ASDA), a biodegradable, and therefore, environmentally benign novel chelating reagent. It was found that zinc exists mainly as ZnO, whereas Pb probably as PbOHCI and PbO, and the easily soluble components in SFA are KCI and NaCl. Suitable amount of HCI can dissolve all of lead and zinc from SFA. Sulfuric acid can selectively extract zinc leaving lead in the residue. Ethylenediaminetetraacetic acid (EDTA) is an effective chelating reagent to extract both zinc and lead. Although ASDA and diethylene¬triaminepentaacetic acid (DTPA) can selectively extract more than half of lead from SFA, it would by no means be regarded as highly effective reagents for the extraction of these metal values. Keywords: Lead, Zinc, Secondary fly ash, Leaching, Dissolution

Jan 1, 2002

By Shane Andrews, Gustavo Vasquez, S. K. Varma

"The effect of solutionizing time on the corrosive wear behavior of 2014 aluminum alloy has been studied using the impact and continuous mode of scratching techniques. The transient currents (TC) evolved during the scratching of the alloy shows a linear dependence between the TC and the solutionizing time. Higher TC values at longer solutionizing time may be associated with the changes in the concentration of quenched-in vacancies, grain sizes and dislocations generated during scratching. These factors can either create (a) anodic sites or (b) pitting corrosion resulting in the generation of transient currents. The results have been compared with the similar study carried out for 6061 aluminum alloys. This 6061 aluminum alloy shows similar behavior but the rate of TC generation per unit solutionizing time is much lower than 2014 aluminum alloy. The morphological changes in the impact scratches and the TEM investigation in the scratch have been presented in this paper.IntroductionThe technique of studying corrosive wear of composites of 6061 aluminum in the monolithic and reinforced forms has been reported in the literature [1]. Two modes of scratching, consisting of impact and continuous, in a corrosive environment indicate that the composites, containing 0.10 and 0.20 volume fractions of alumina particles (VFAP), have higher corrosive wear rates than the monolith. A graph between the transient current (TC) generated during the impact scratching as a function of solutionizing time at 540°C indicates linear relationship between them. A similar slopes for the composites were observed and the TC values were less for the composite containing lesser VFAP."

Jan 1, 1998

By Zhonglin Ye, Yifeng Shi

"This paper has outlined forms of Au & Ag losses in copper smelting process and methods for increasing Au & Ag recovery, analyzed factors influencing Au & Ag recovery in copper converting process, presented Au & Ag behavior in copper electrorefining process, and reviewed effect of current density/electrolyte circulation rate during electrolysis and surface finish of cathode on Au & Ag losses. Measures and research direction for decreasing Au & Ag losses in electrolysis have also been introduced. Based on Au & Ag behavior in copper electrorefining process and previous studies by others, new approach for increasing Au & Ag recovery in copper smelter has been discussed. And brief comparison has made between continued multiplication method and equilibrium method application in the case of calculation of Au & Ag recovery in copper smelter.IntroductionAs gold and silver are the major by-products from copper smelting process, efficient Au & Ag recovery has become one of the key approaches for copper producers to increase economic efficiency. With similar physicochemical properties, Cu, Au and Ag belong to the first subgroup of elements in the same periodic table. Au and Ag will be enriched into Cu phase firstly when both matte-slag phase and copper-matte phase appear in copper smelting process. However, great changes have taken place in Au & Ag proportions into individual phase due to changes of physicochemical conditions in each smelting process. Metallurgists at home and abroad have carried out a great deal of pilot plant tests and laboratory tests in order to increase Au & Ag the former Soviet Union with regard to Au & Ag losses in copper smelting process in the 1970s and 1980s, and he proposed solutions to increase Au & Ag recovery in copper metallurgical plants. As more than 20 years passed, Jingchun Lu's paper, Discussion on Increasing Au & Ag Recovery in Copper Smelting System, remains as a literature of the most comprehensive study. Based on Jingchun Lu's literature, the authors of this paper discussed new approaches to increase Au & Ag recovery in copper metallurgical plants with combination of many researches done by other researchers for over 20 years."

Jan 1, 2013

By Huimin Lu, Qiang Li, Jingbo Xu

"The smelting reduction of V-Ti bearing beach placer by combined rotary hearth furnace and direct current arc furnace was studied in laboratory. It takes the aid of back propagation (BP) neural network theory to build the nonlinear mapping relations between the crucial process variables such as content of carbon, temperature and time and the degree of reduction. Then by the integrating BP neural network and genetic algorithm (GA), the optimized process parameters for the high degree of reduction were searched. The comparisons between experiment results and neural network simulation results show that GA-based on BP method can predict the degree of reduction with higher prediction accuracy. Calculations show that the integrated energy consumption of new technology is 580kgce/tHM, less than the current existing blast furnace.IntroductionThese V-Ti bearing beach placers (VTBBP) are secondary Fe-rich minerals formed by rivers, ocean waves, ocean tides and ocean currents on beach zones, their useful minerals are V-Ti magnetite ores. On Asia Pacific zone, such as Japan, China, Philippines, Indonesia, Australia and New Zealand, the VTBBP have large reserves and wide distribution. But so far, the VTBBP are not still comprehensively utilized. Therefore, in this paper, a combined rotary hearth furnace technology and arc furnace smelting method is studied for comprehensive utilization of the VTBBP. The main objective of this paper is to find optimum operation conditions for the production ofV-bearing iron and titania-rich slag from the VTBBP by means of the laboratory testing.Recently, neural network (NN) expected to be able to provide an effective tool because of its advantages, which describe nonlinear mapping relations. With the characteristics of strong selflearning, self-organization, robust error toleration and accurate nonlinear relation approximation, artificial neural network can be applied to nonlinear process modeling based on sufficient training. Back-propagation (BP) training algorithm is probably the frequently used one in practical application. Genetic algorithm has parallel search strategy and global optimization characteristics, which makes the trained neural network being higher classification accuracy and faster convergence speed. So it is necessary to combine neural network and genetic algorithm. The nonlinear relationship between input and output presented by NN and the global optimal function of GA are abroad applied in the engineering and scientific research [1, 2]. So these methods supply an efficient path to solve the above problems. At present, it is common to study the optimization of process parameters by orthogonal experimental design, the method combining neural network and genetic algorithm is a novel and better method than orthogonal experimental design. Tills study organized the above advantages to optimize the process parameters for comprehensive utilization of the VTBBP."

Jan 1, 2012