MATERIALS RECYCLING PROCESSES AND PRODUCTS

In this study, active zinc oxide containing over 98 wt. % ZnO was synthesized by hydrometallurgical process starting from waste zinc powder (blue zinc oxide). In the first step of the study, 95 wt. % Zn containing waste zinc powder was reacted with diluted sulphuric acid solution and then Fe content was removed from the system by addition of hydrogen peroxide. In the second step, zinc sulphate solution was mixed with different stoichiometric sodium carbonate solution. After solid / liquid separation, obtained zinc carbonate was dried over 12 hours. In the last step, calcination of zinc carbonate was carried out at different temperatures and time to set the alternative quality of active zinc oxide. Elemental analysis of the waste zinc powder and active zinc oxide was performed by using XRD, XRF, BET and AAS.

Crude zinc oxide, the collected fume from a Waelz kiln, is calcined in a rotary kiln to remove volatile salts (such as lead chloride and potassium sulfate). Accretions develop in the calcination kiln. The work reported here examined the fundamental cause. It is found that a small amount of liquid forms at the calcination temperature, and binds together the zinc oxide, similar to the mechanism by which moisture increases the strength of wet sand. Both potassium sulfate and calcium silicate cause liquid formation. Laboratory trials tested whether the composition of the binding liquid responds to additions of silica and alumina. The calcium silicate appears to contain all of the calcium oxide and silica from the feed material (crude zinc oxide); It is possible to manipulate the composition and amount of the calcium silicate by silica additions to the feed, but the calcium silicate does not respond to alumina additions. While this work has clarified the likely causes of accretion formation, it does not lead to any obvious solutions. It does not appear possible to eliminate all liquid in this process, since potassium sulfate (with a melting point of 1069°C) is one of the binder liquids.

The main mechanism of failure in most of collide is impact. Absorption energy and fracture toughness are important factors which could avoid failure of material or decreasing deflection in impacts, so they reduce cost and health damage to trucks or their passengers in accident. In addition, weight has two different significant roles in the vehicle. The first one is to reduce the cost and energy. The second one is to decrease the mass of the truck for reduction of kinetic energy of moving vehicle, which reduces the impact energy in crash. Hence, using of light material with high impact absorption energy and relatively low cost is important in vehicle industries. Aluminum foam is an excellent material in this purpose. It could be used in bumper and chassis even in body work of automobile to reduce the accident damage. Furthermore, using of Aluminum Foam in frames of automobile could have useful properties in reduction of damping vibration. The aim of this paper is to identify the technological aspect of a project for Aluminum foam to decrease its specific mass below one gram per cubic centimeter to optimize the absorption energy to the weight.

Efficient use of building construction materials are a key to success of a construction project. Nowadays, the successful selection of construction materials has to be based on stabile construction designed. Kosovo needed by the Customs Union agreement which came into force in 1997to remove the technical barriers in trade within a limited period, in order to ensure free circulation of products as required by the harmonization with the European Union process, and. In order to remove the negative effects of these barriers on international trade, some regulations were passed both within the World Trade Organization and regional authorities, in order that such regulations do not create new barriers against trade. The activities of the building- and construction sector are not only of influence on the human and quality of life, but it is also a sector with a high employment potential which relies heavily on local industry with close ties with all the other sectors, primarily the manufacturing industry. The aim of these Directives is to ensure free circulation of the construction materials, which are manufactured in our country, within Kosovo and the European Union member countries. Conformity with the harmonized standards, issued by the EU Commission is obligatory to ensure compliance of the construction materials with the directive. Basic Requirements: - Mechanical strength and stability (Disaster Directives)- Safety in case of fire (Fire Directives)- Hygiene, health and environment (Drinking Water and Hazardous Materials Directives)- Using Safety (Health and Safety Directives)- Protection against noise (Noise Directives)- Energy Saving and heat conservation (Heat Isolation Directives). “Safe Product� within the context of this Directive is the product which does not bear risk within the normal using period and under normal conditions or; Which bears acceptable amount of risk and meets the basic requirements such as protecting public health, environment, flora and fauna.

Carbon nanotube (CNT) bundles into ropes/ribbons were synthesized by expensive methods, arc discharge and chemical vapour deposition (CVD) using transition metal catalysts e. G., Co, Ni, Fe and Mo [1,2]. We produced CNT ribbons by pyrolysis of a sustainable waste material. Different geometrical structures, e. G.; Knotted and twisted, U- and spiral-shaped CNT ribbons were observed in the images of scanning and transmission electron microscopy. The widths of the CNT ribbons measured varied in the ranges 18 ~ 80 nm. X-ray photoelectron spectroscopy analysis showed five types of carbon binding peaks, C–C/C–H (~77%), C–O–H (~9%), –C–O–C (~5%), C=O (~5%) and –O–C=O (~3%). The ratio of intensities of G and D bands, IG/ID was 1.61 analysed by Raman Spectroscopy. CNT ribbons grown on the surface of catalyst have potential for the fabrication of high-strength composite materials with polymer and metal.

Carbon nanotube (CNT) bundles into ropes/ribbons were synthesized by expensive methods, arc discharge and chemical vapour deposition (CVD) using transition metal catalysts e. G., Co, Ni, Fe and Mo [1,2]. We produced CNT ribbons by pyrolysis of a sustainable waste material. Different geometrical structures, e. G.; Knotted and twisted, U- and spiral-shaped CNT ribbons were observed in the images of scanning and transmission electron microscopy. The widths of the CNT ribbons measured varied in the ranges 18 ~ 80 nm. X-ray photoelectron spectroscopy analysis showed five types of carbon binding peaks, C–C/C–H (~77%), C–O–H (~9%), –C–O–C (~5%), C=O (~5%) and –O–C=O (~3%). The ratio of intensities of G and D bands, IG/ID was 1.61 analysed by Raman Spectroscopy. CNT ribbons grown on the surface of catalyst have potential for the fabrication of high-strength composite materials with polymer and metal.

A technology was developed to produce high strength building materials by treating slags with CO2 at elevated pressure (20 bar) and temperature (140°C) without addition of binders. The carbonated materials can compete with concrete products (C35/C45) and have excellent environmental and technical properties. The materials have the additional advantage of sequestering 180-200 g CO2/kg slag. The process makes use of a unique combination of existing technologies commonly used in the construction industry. Building of a pilot installation for treatment of 10.000 ton of slag per year is planned for the near future.

Lead ore winning started in Zerjav-Slovenia in 1746. Large demand for lead in 1846 resulted in the first largest modernisation of production, which has been continously updated ever since. In 1990 MPI Reciklaza d. O. O. Was transformed into one of the most modern secondary lead smeltery in this part of Europe. In 2002 MPI Reciklaza became part of the group TAB Batteries d. D. This connection brought new investments and improvements into recycling process. This presentation describes recycling proces in company MPI Reciklaza d. O. O. All the improvements made in last years and the process of battery production. In the presentation will be presented usage of all products of recycling: -Lead as a material for our battery production , - PP as a material for production of battery boxes and- Gypsum as material in the cement industry. Recycling proces of TAB-MPI group represents a complete loop from the scrap to the end product.

This paper describes the characteristics of copper smelter slag, which are very influential in the process of flotation. Special attention was paid to the stability of the suspension in the flotation conditions. Zeta potential and sedimentation tests were conducted under different values of pH, concentration of solid and concentration of flotation reagents. In addition to these some mineralogical investigations were carried out on samples of slag in the piece as well as in briquette of milled samples by ore microscopy. Appearance of solid copper bearing phase and their size and shape were given in the paper. On briquettes of granulated slag sample the liberation results of the copper bearing phase under different conditions of grinding and flotation were shown and discussed in the paper. And finally some recommendations for the reprocessing of copper smelter slag in order to obtain copper by flotation were given. All test were conducted on samples of smelter slag from Mining and Smelting Bor, Serbia.

An electrochemical sensor for lead detection within a lead recycling system with concentrations in the range from 50-1000 uM is reported. The sensor uses carbon paste electrodes modified with cyclam-functionalized exfoliated graphene oxide (EGO-cyclam-CPE). The interaction of Pb(II) ions with the cyclam ligands on the surface of the electrode in aqueous media is studied using cyclic voltammetry. The presence of cyclam ligands enhances the redox activity of Pb(II) ions in a 0.1 M acetate buffer. In order to determine the electrochemical behaviour of EGO-cyclam-CPE, parameters such as voltammetric scan rate, pH and type of buffer are also optimized. The Pb(II) detection limit is found to be 18 uM.

The paper shall present the theoretic, quality, technology and development aspects, related to the pyrometallurgical treatment of the lead-bearing wastes and other secondary materials.

A practical usage of urban mine and its system formation are one of the most challenging and important issue to be progressed. In Japan, Home Appliance Recycling Law and End-of-Life Vehicle (ELV) Recycling Law are enforced since 2001 (former) and 2005 (latter). These Laws may play a part to reduce illegal waste disposals and to properly control hazardous substances. However, in the case of recycle, it seems less affected since a further recovery procedure, for example recovery of less-common-metals, has not additionally and adequately installed. Mainly the previously-existing recycling processes are operated. According to the sustainable resource management, further progress for the special minor metals recovery may become the key issue. On the other hand, there is no regulation and legislation for collecting small-sized E-scrap such as cell phones, mobile audio players, digital cameras, and etc in Japan. The contain ratio of special minor metals in small-size E-scraps can be much higher than that in home appliances and ELVs. To help to figure the operability of special minor metals recovery from small-size E-scraps, we will introduce the estimation on how much less-common-metals are accumulated in a society through all E-scrap from home appliances, ELVs and small domestic appliances in Japan. Then we will introduce experimental trials of collecting small-size E-scrap operated in some parts of Japan and how to recover minor rare metals from them

One of the most pressing problems facing metal casting industry today is the disposal of foundry by-products. Foundry industry produces a big amount of wastes (or by products?) that generate in every step of foundry process. Cast iron foundries generate next types of wastes: Used sand mixtures (92,93%), slags (3,5%), used refractory material (0,17%), fly dust from furnaces (1,42%), dust comes from sand mixtures – preparing and handling (0,66%) and dust from finishing operations – castings cleaning, grinding (1,32%). Disposal of foundry by-products is a large cost for foundry industry, whether disposal occurs in company-owned facilities or in municipal or privately owned landfills. The authors have been attending to properties and treatment of foundry wastes ( above all foundry dusts and slags) for some years and on the base of results obtained during their research the possibilities of wastes (by-products?) recycling in steel and cast iron foundry will be proposed (with regard to condition in Slovak foundries).

In recent years, there has been an acceleration of the interest in cost reduction of titanium production which is closely related to electrolysis process. The energy consumption to produce metal magnesium from magnesium chloride in molten salt electrolysis is required 70-80% of the total energy for titanium sponge production. In this reason, efforts to reduce the energy consumption of electrolysis have continued practically. There are a number of main factors which affects in energy consumption of electrolysis process; The composition of the electrolyte, the distance between anode and cathode, the flow of the electrolyte. In this paper, therefore, an effect of the factors mentioned above on the energy consumption of electrolysis was studied with monopolar diaphragmless electrolytic cell have originally designed. The energy consumption is lower in electrolytes containing a large proportion of sodium chloride and smaller amounts of calcium fluoride. The optimum composition of the electrolyte for the production of magnesium should be NaCl 50~60 %, CaCl2 20~25 %, MgCl2 20~25 %, and CaF2 2~5 %. The energy consumption markedly decreases if the electrode distance is reduced which means the effect of the electrode distance on the energy consumption is the stronger.

The company Gallooplastics has developed an integrated process for plastics recovery and recycling from shredding of automobiles. This process occurs after the crushing and metals sorting. The none metallic fraction of automotive shredder residue, is then processed by a cascade of physical and mechanical sorting that leads to separation and recycling of Polypropylen ans Polyethylen fractions and to the preparation of a derived fuel that can replace quantities of coal and coke in the production of steel in blast furnaces. This process has been validated during a test campaign conducted in collaboration with BMW, and the company Scholz. A life cycle assessment of the complete process of shredding of cars and recovery of plastics fractions was performed. This analysis shows that there is a real environmental impact reduction with the recovery of plastics fractions compared to dumping and production of new polymeric materials. The reduction is particularly important for greenhouse gas emissions and energy resources consumption. Recycled plastics have properties sufficiently powerful for reuse in the manufacture of automobile parts.

The slag of electric furnace, which came from melted nickel oxide ore from production of Ferronickel in Drenas, Kosovo, has acidic attribute. Slag components are SiO2 and CaO, oxides that influence in their physic and mechanics characteristics. Cooling and granulation of slag, conform standard requirements affect in their applied technology to the consumable layers of asphalt concrete for roads of all charges. The designing of recaptures added from this slag in the same time would also affect improvement of surface layer. The program of prearrangement of ferronickel slag, projection of preliminary mixing properties and research of the asphalt concrete layer consumable is based on standard methods, EN (933, 13036-4, 13036-1, etc..). In this project are proven data gained from research results regarding the skid resistance, depth of surface texture, resistance to erosion, water absorption, etc. Research results have argued the fact that slag besides that can use for developing of asphalt concrete adding of this slag in mixing silicate clinker indicates improvements in terms of characteristics to surface layer of consumable asphalt and log time usage.

Kroll process is a well-known extraction process which produces titanium. It consists of 4 steps containing chlorination, reduction, vacuum distillation, electrolysis. Electrolysis process is not directly related to production of metal titanium, but it has an important role being recycling of by-product, magnesium chloride. During this electrolysis process, metal magnesium is oxidized at cathode and chloride gas is reduced at anode. Chloride gas in forms of bubble makes a effect to flow of the molten magnesium salt, and flow is a significant factor that determines efficiency of process. Therefore, a three-dimensional mathematical model was developed to investigate the flow of the molten magnesium salt, and validated against data of pilot scale experiment. The model predicted the flow field with applying change of variable such as cell temperature, distance between electrodes, and design of electrode. And operating parameters which optimize the electrolysis process were suggested by simulation for productivity and cost savings.

Generation of new quantitative data and findings of the research allowed us to improve significantly the quantity and the quality of the statistics available on international trade, use and prices of copper scrap for some key countries. Quantitative estimates of copper scrap in direct melt should contribute to improved knowledge of this market. An important achievement was to improve the understanding of the role of scrap in specific economies and semis products. The role of China, India, the Russian Federation, Japan, the EU27 scrap market and other regions in the global flow of recycled copper is now better understood and there are more figures available. The critical role played by scrap via direct melt into some semi fabricators production, in particular on brass mills and alloy products was observed. The secondary market does not show dynamic behaviour in the case of copper mine oversupply, but can play a critical role in an scenario of tight copper concentrates, limited expansion of SX-EW cathode production and sustained recovery of the industrial production, confirming the buffer role of scrap in the global refined copper market. The study of recycling policies and trade regulations affecting scrap produced useful outcomes. Regulations affecting sectors are key drivers for copper scrap recycling: Electronic waste recycling is receiving increased attention, as well as automobile recycling, but more important sectors for copper such as building, construction and industrial waste recycling have not been promoted as needed. Regulatory leadership in end-of-life products recycling is moving from Europe and Japan towards China, the USA and developing economies, while Europe focuses more on high quality copper scrap regulation. In the case of the study of trade regulations we found that the use of export restrictions on scrap as a tool to promote more value added production as semis was an important finding. Also we observed that the “waste� status of copper scrap supply can work as a non tariff barrier against more international trade of copper scrap in some regions, at a time when the strict waste regulation is seldom enforced domestically. An improved knowledge of the role of the copper scrap market in relation to other copper commodities such as copper concentrate is another key outcome: The research allowed us to confirm that the availability of old scrap is directly linked to the shortage in copper concentrate markets, which has been induced by the growth in the Chinese demand. Custom smelters use more and more copper scrap together in a mix with available concentrates. Substitution between scrap and concentrate at the smelter level is a next area that ICSG should study in more detail and with more active involvement of the smelters and refineries. The same is valid in relation to the substitution between refined and scrap direct use at the level of copper and copper alloy semis fabricators. The option of developing large scale surveys in some regions and indirect input – output flows in regions where data is harder to obtain is an option to improve global knowledge on scrap use. Chinese imports are by far the major driver of this market. In consequence China scrap trade and its regulatory developments on scrap, as well as domestic enforcement of its recycling laws, are expected to be among the most important issues affecting this market in the future. ICSG knowledge of the scrap demand in China from secondary smelters has been improved, but much more remains to be done to know the metal scrap demand by small size brass plants and metal fabricating operations in China, not based on copper only.

Governments are starting to notice the real issues around material availability and the criticality of some metals that are byproducts of mined materials and have an inelastic supply pattern as well as being used in the highly consumer popular high-tech applications. Industry is also starting to pay attention to the positive economic benefits of having a sustainability policy in place as Umicore can demonstrate. Ten years ago, Umicore made fundamental choices by concentrating on two activities, i. E. The development of high quality materials with extensive technology content and the recycling of precious and rare metals, which form the basis of many of these high-tech materials. As the materials provider for rechargeable batteries, catalytic converters, solar cells and other high tech applications and as the recycler of end-of-life materials from these same technologies, Umicore has been able to illustrate and effectively close the material loop. Today, over half of Umicore turnover and profits is derived from this wide range of Clean Technologies. This illustrates the success sustainability as a strategy is having for Umicore.

The increasing use of polymeric materials and the subsequent solid waste generation has led to the necessity of controlling the environmental impact through the polymer recycling process. The aim of this work was to make virgin polypropylene (PP), polyestyrene (PS) and polyvinyl chloride (PVC) blended with their corresponding recycling material (100/0, 84/16, 68/32, 50/50, 34/66, 18/82, 0/100) via injection molding, and evaluate their hardness and impact fracture behavior. The impact testing method was Charpy impact test as for hardness measurement hardness Shore method was used. For all the cases hardness increased when increasing the recycled material percentage, as the contrary behavior was observed for impact strengths. These results suggest that the recycled material percentage has direct influence on mechanical properties of virgin polymers.

Processing technologies addressed to recover different products from complex waste, characterized by the presence of different materials and associated contaminants, need to be extremely powerful, since they must be relatively simple to be cost-effective, but also accurate enough to create high-purity products and able to valorize a substantial fraction of the waste materials into useful products of consistent quality in order to be economical. On the other hand, the potential market for such technologies is large and the boost of environmental regulations has made many industries interested both in “general purpose� waste sorting technologies, as well as in developing more specialized sensing devices and/or inspection logics for a better quality assessment of specific products. The development of these actions passes through: I) the definition of advanced sorting techniques able to deal with complex associations of materials and ii) a suitable design rules in adequacy with the technological limits of the sorting processes existing in the recycling industry. The lecture is addressed to present innovative devices, software tools and integrated software and hardware architecture in solid waste recycling finalized to perform a full quality control of fed/recovered waste streams through the definition of new sorting and/or control logics that could be profitably applied, in “on-line� control architectures, at industrial plant level.

A presentation is given on the worldwide unique closed battery recycling loop that the German company group BERZELIUS METALL GmbH characterises. BERZELIUS treats and recycles automotive and industrial batteries, scraps and lead containing waste in a very efficient way. The group is leader in processing lead, lead alloys, silver, sulphuric acid, sodium sulphate and polypropylene-compounds (Seculene®). The processes and management of the three modern smelters – one primary and two secondaries - as well as a logistic company are described. Utmost attention is given to their state-of-the-art technologies, starting with the secondary smelters BSB and MRU. The treatment of the different components of old batteries is illustrated - i. E. Plastics in the BSB compounding plant with the registered Polypropylene quality Seculene®, paste and grid metals etc – amongst secondary lead which is available in more than 100 qualities according to customers’ specifications. The integration of an incinerator for hazardous wastes at MRU - enabling the recovery of the energy content of toxic wastes - in the allied subsidiaries, provides the closing link for the exemplary recycling of materials and wastes during the production of lead, plastics, and sulphuric acid. Technological leadership in the production of primary lead and sulphuric acid assures the most modern QSL process at the BBH smelter. The range of products includes high purity lead, silver, copper/lead matte and BERZELIT® slag. Forward-looking was the latest expansion of the sulphuric acid plant with a significant capacity increase. Responsibility for the environment is a matter of principle at BERZELIUS Metall: The production subsidiaries were among the first of this industrial sector to be certified as users of an integrated management system of quality, workplace safety and environmental protection. The application of environmentally sound processes, an intelligent management and control of materials, and the encapsulation and hooding of plants and warehouses, lead to a closed-circuit recycling of resources, which the efficiency of the measures employed. The reduction of waste releases, the continuing decrease of emissions and the steady reduction of the blood lead levels and lost time accidents are impressive proofs of this strategy.

Due to always getting stricter environmental legislations as well as increasing land filling fees the efforts for treating residues from metallurgy are increasing. In case of filter dusts from metallurgical industry the high zinc bearing EAF-dusts are one main source for the recovery of secondary zinc. Although the waelz kiln is state of the art, there are investigations to improve the recycling performance, to generate less newly residues, to achieve a better product quality and going hand in hand with that to prevent the further treatment in the primary industry. One concept which seems to yield fruits is a two step concept, which is investigated at the department for nonferrous metallurgy on the University Leoben/Austria, with a reducing metal bath as a core part. This would open the opportunity to recover more than one valuable metal, next to a cleaner product (ZnO) and less slag compared to recycling processes which are in use at the moment. Additionally an advantage is the high flexibility of this concept, due to that it is adaptable for a wide range of residues, like dusts from secondary copper industry, neutral leaching residues or even waelz slag.

To date, the lead-acid electrochemical system is one of the most successful ever developed and even now no other system is yet able to compete on cost grounds. Despite having the second lowest energy to weight ratio, the lead-acid system is able to supply high surge currents and therefore maintain a relatively large power-to-weight ratio. Add to this their low cost, well established worldwide manufacturing and recycling infrastructure, wide availability of raw materials, and their reliability of operation, lead-acid batteries are still a very attractive and viable source of power. The main disadvantage to the lead-acid system is its weight, which is due to the heavy lead electrode; This is one of the areas other chemistries such as the Lithium (Li) ion system have the main advantage. This has resulted in so much emphasis on producing Li based batteries for Electrical Vehicles (EVs) that the lead-acid battery, the most established automotive battery for over 100 years, has not been seriously considered for the next generation of EVs and Hybrid Electrical Vehicles (HEVs). This is particularly surprising given the cost advantages are by a factor of 10.In this project, foundations will be laid for the next generation of low-cost, light weight and high energy density lead based electrochemical systems. A potential method of producing nanoparticles for use in lead acid batteries to increase the level of efficiency in these systems is explored. PbO precursors formed by leaching-crystallization-combustion method have been characterised using X-ray diffraction (XRD), secondary electron microscopy (SEM), BET surface area analysis, elemental mapping and Cyclic Voltammetry. The microstructure and size of the active component from commercial sources was successfully altered using the method and depending on the mode of processing, different microstructural and chemical characteristics were observed.

Zinc containing residues such as dusts from steel, copper or lead industry have become an interesting secondary raw material because of stricter dumping regulations and high prices of the contained metals. Nevertheless most of the existing recycling routes are pyrometallurgical ones and therefore the melting behavior is of high importance. Simple chemical analysis of the elements does not offer sufficient information due to their complex formation. The paper describes the study of the morphology of such residues which act as a base for detailed investigations with a high temperature melting microscope. The results of these laboratory scale trials give detailed information about the influence of slag components, atmosphere and degree of metallization on the sintering and melting points and with this offer a base for the development or optimization of future recycling processes.

Increased demand of metals has driven the accelerated mining and metallurgical production in recent years. For many metals the world is seeing a critical problem in depleting primary resources of metals and minerals – “metals scarcity�. In parallel, the mining and metallurgical operations generate enormous amount of solid residues and waste such as tailings, slags, flue dust and leach residues. In these types of solid waste, the valuable metal contents are relatively low for the current concentration and extraction technologies. They are mostly dumped, land-filled or used in limited secondary applications. Here two issues are getting increased attention from the public and the industry: (1) environmental pollution, (2) treatment of wastes from metal industry. Recycling and recovery of the metals and materials from these large streams of waste become a natural solution. The current technology and processes for primary metals production are not readily applicable for direct metals extraction from these waste materials. In the present paper, the resources of the existing solid waste are reviewed, and current technologies and R&D trends are discussed. The recent developed technology and flowsheet from authors’ group are presented for the potential solutions to waste and resource problems: Zinc recovery from various industrial wastes, vanadium recovery from fly ash, and silicon recovery from wafer sawing kerf. Technological and economical challenges are addressed. It is very important that the processing of secondary resources should have minimal or no environmental impact.

In this work is developed in the laboratory a methodology for extracting the precious metals gold and silver and platinum group (palladium, iridium, rhodium and platinum) present in electronic waste. To determine this, it examines the state of the art in the recovery of metals from electronic waste, selected, prepared and characterized by SEM techniques and X-ray diffraction eight types of electronic components found in electronic waste are defined and mounted experimental techniques via hydrometallurgical and electrolytic recovery under a fractional factorial statistical model that presents the data of the response variable. Electronic components correspond to the categories called pin serial and parallel port card, RAM, processor pins, integrated surface, diodes, resistors, capacitors, and transistor; Components which together are subjected to mineral recovery stages of size reduction , magnetic separation, selective leaching, electrowinning, cementation, refining and metal collection. The fundamental stage selective leaching gradually develops through the sequence aluminum, lead - tin, copper, precious, nickel - zinc, platinum group, controlling and operating the electrochemical variables to obtain liquor input stage electrowinning . Liqueurs metal species recorded for the gold, silver and platinum group is subjected to electrowinning defining the parameters of current density, pH, residence time and temperature in the electrowinning cell. The remaining liquor will be subjected to chemical analysis to recognize the metal fraction content and set the corresponding mass balance.

Microwave Assisted Recovery of PlatinumT. Gerdes, M. Willert-PoradaUniversität Bayreuth, Lehrstuhl für WerkstoffverarbeitungPlatinum metals are important industrially applied catalysts. Currently, exhaust gas catalysts account for approx. 10 % total Pt use, however, based on expected demand soon probably 20 % of the total consumption of platinum group metals will be allocated to exhaust gas catalysis in automotive applications. Materials used in cars have to be recycled. Currently the recycling rate of platinum is very high. Consequently, the primary Pt-production equals the secondary production. In view of the rising volume of secondary Pt-production the economy of Pt-recycling gains importance. Primary as well as secondary processing of Pt consists of numerous dissolution and precipitation processes with their individual efficiency governing the overall economy of the process. In particular, only Pt of exceptional purity is capable of catalytic activity or superior refractory metal properties. Consequently, unique oxidation and reduction steps have to be applied in order to insure enrichment and purity of the refractory metal. The entrapment of impurities upon subsequent repetition of dissolution and precipitation steps is an issue in current state of the art Pt-purification and recycling processes. The aim to use microwave heating upon purification processes is to enhance dissolution and precipitation of Pt metal without retention of impurities, by selective overheating of the leaching agent. Microwave heating enables pulsed application of energy, thus accelerating dissolution of Pt-sponge and its precipitation while limiting sintering of the Pt-sponge accompanied by impurities entrapment. A significant reduction of processing time can be achieved by utilisation of microwave assisted processing conditions. In the paper a comparison of conventional and microwave assisted process is presented. The influence of MW-power control (power level, pulse length, local plasma ignition) on the platinum sponge morphology and details of the re-dissolving process of platinum sponge in a chlorine saturated hydrochloric acid upon microwave heating are discussed

Waste incineration has nowadays become more common, so the new kind of slags and ashes are to be managed in Finland. Treatment and disposal of these residues affect significantly the operating costs of a waste incineration plant, and when disposed without utilisation the slags and ashes will also burden landfills. Meanwhile there are also a number of national and EU-level development initiatives ongoing in Finland to enhance the reuse of waste materials. The reuse of bottom ash requires suitable upgrading processes, as it is not as such, without upgrading suitable for material reuse. The aim of this ongoing co-operation project of VTT and GTK is to process a novel reuse material suitable for earth construction purposes from MSWI bottom ash, and to develop innovative waste material upgrading technologies based on current ore enrichment processes. The development work has shown some promising results, most of metal elements can be enriched by using mineral processing technology.

Recovery of valuable elements from non-ferrous slags has been attended gradually with decrease of natural mineral resources for extraction of metals. In this work, the mechanism of reduction of Fe and Ni elements in molten slags and feasibility of Ni-Fe alloy prepared from the Fe and Ni elements-containing non-ferrous slags were investigated using carbothermic-electrochemical reduction method. The experimental result shows that the carbothermic-electrochemical Reduction Method was used to obtained Ni-Fe alloy with carbon-free from Fe and Ni elements-containing molten slags, in which the reduction of Ni2+ is easier than that of Fe2+ into Ni-Fe alloy. Moreover, the nonferrous slags was pretreated for desulfurization at 1373K for 5hours in air, pre-reduction at 1373K for 4 hours using coal as a reductant and melt-separating between metal reduced and slags remained at 1773K for 0.5 hour, and then was reduced using the carbothermic-electrochemical reduction method which also plays an effect of oxygen potential sensor to displays the reduction rate and the oxide activity in the slags by the current and potential between the electrodes. Finally, a low S, C contents-containing Ni-Fe alloy with compositions of 98.39%Fe, 0.83%Ni, 0.49%Cu, 0.18%C and 0.026%S was obtained from the non-ferrous slags, which is a good material for making a weathering resistant steel.

Among Plastic Solid waste (SW), polyolefins represent a very important family of polymers, constituting more than a third of the total plastics consumption in Europe, but they are the least recycled plastic materials, as a consequence polyolefins waste recovery represents one of the major opportunities in PSW. The possibility offered by HyperSpectral Imaging (HSI) based sensing architectures has been investigated in order to develop innovative sensing architectures and logics finalized to perform polyolefins recognition. Due to the high degree of innovation of HSI and the relative low knowledge, in terms of available hyperspectral libraries, related analytical tools and HSI based recognition strategies, a study was thus carried to explore the potentialities of the proposed approach. The investigations have been thus carried out in two steps: I) collection of a large number of post-consumer polyolefin samples characterized by different attributes and ii) systematic application of different spectroscopic sensing techniques (FT-IR spectroscopy, by Raman spectroscopy and by hyperspectral imaging) in order to identify the different plastic particles to be recycled, with particular reference to the polyolefins present inside complex plastic wastes. The spectral signatures collected adopting the different techniques have been thus detected, analysed and compared. The main parameters that allow to perform the recognition of the polyethylene (PE) and polypropylene (PP) have been defined, with particular reference to the hyperspectral imaging innovative technique. The analytical strategies can be utilised to define sorting and/or control logics to be applied in “on-line� control architectures to directly act at industrial plant level.

The Swedish iron ore contains about 0.1%V. In a blast furnace the vanadium is reduced to the hot metal which has a V-content of about 0.3%. During the LD-process, the vanadium is oxidised and ends up in the LD-slag. The high V-content, 2-3%V in the slag leads to a very limited external application of the slag in Sweden. At the same time it is a huge loss of an important resource. Since 2004, MISTRA - the Swedish Foundation for Strategic Environmental Research has together with the steel and mining industry in Sweden and Finland initiated and supported a long term project, called VILD (Vanadium In LD-slag), aiming at efficient recovery of vanadium in the slag and at the same time a useful slag product with low V-content. The aimed concept consists of a reduction step and a phosphorus removal step. This paper will highlight some of the results obtained so far with focus on the various metallurgical reactors used for the slag reduction. The available amount of vanadium in the unused Swedish LD-slag is about 5000 tons corresponding to a value of about US$ 150 millions every year based on the current vanadium price. The environmental potentials of the project include annual savings of more than 1 million tons CO2 and 2 TWh of energy according to the preliminary LCA assessment. For the reduction trials, both pilot and industrial trials have been performed and it has shown that it is possible to reduce the vanadium to below 0.1% in the slag. This will open a wider market for the reduced slag products. The property of the slag product will also be discussed.

Recycled aggregates from construction and demolition waste (CDW) are commonly classified in coarse (CRA) and fine (FRA) fractions. Unlike CRA, which are now widely used in different applications including concrete, FRA (minus 4 mm fraction) are used as low-value products (for roads, landscaping and landfilling). One of the main reasons for this is the poor knowledge of their properties which prevents their application in added-value products such as concrete. The development of a methodology to classify FRA aiming at their application in different applications relies on the physical and chemical-mineralogical characterization that is conditioned by the composition of the CDW and by the processing they were subjected to. This paper describes the experimental work carried out aiming at the characterization of this fraction of recycled aggregates and of its influence on the properties commonly used to predict concrete behavior. For this purpose, samples of 7 Portuguese CDW recycling plants were collected. The criteria to choose the plants were the geographical location and the type of CDW processing at the recycling plant. The former was due to the geological environment where the materials used in the construction were collected and to the building techniques employed, because they are most probably related with the composition of CDW and the resulting aggregates. The CDW processing diagram, equipment type and parameter settings may also affect the physical and the physical aggregate properties. The particle size analysis of each FRA was carried out and the +1 mm fraction was manually separated in different materials (e. G. Aggregates, wood, plastics) for composition evaluation. The inert fraction was grinded and dissolved in HCl for carbonates and other soluble minerals quantification. Then, a chemical-mineralogical characterization of the remaining sample by means of X-ray fluorescence and X-ray diffractometry was made. Finally, the physical properties of the aggregates that are commonly used to predict concrete behavior sucha as bulk density, water absorption and voids percentage were determined. The relationship between these and the physical and chemical-mineralogical characteristics was obtained leading to classification of FRA in different categories.

Kovohute Pribram operates technology of whole batteries smelting in a blast furnace built in 1997 according to know how Varta, Germany. Value of polypropylene and new European Directive on Batteries and Accumulators setting obligation for minimal recycling efficiency forced Kovohute to implement technology of polypropylene separation from batteries prior their smelting in the blast furnace. This presentation describes the procedure how the separation method has been implemented and the problems which were solved. In the first step equipment for polypropylene separation was built, then, in the second, equipment for its washing and drying. This solution is economic, effective and contributes to green gas emission reduction in the process of lead acid batteries recycling.

The smelting process of nickel oxides ores in the electric furnace is almost slag process, where about 75% of the calcin pass to slag. The designed capacity of the New Ferronickel foundry has possibility to process about 1.200.000 t ores /year, capacity production to produce 11.000 t Ni/year, and 800.000 t slag / year. Until now, about 8 million tons of slag is stored in slag landfill. The stored slag is highly prized raw material for: Construction industry, cements industry (portland cement with slag as additive, metallurgical cements), refractory materials, mineral glasses, bituminized aggregates (asphalt concrete, pavement for paths, etc.). Nowadays this slag landfill is not properly treated and it is one environmental problem. The examination of the Ferronickel slag, show that in addition to numerous opportunities for their valorisation, but excite as well and the limits on the use of such slags as: Balance of slag ingredients (CaO-FeO-SiO2, MgO-FeO-SiO2), structural properties of SiO2 and silicate ions, water granulation, granules composition, mass volume, plasticity, water absorption, etc. These slag limits are research object in research laboratories: Xella-Kosovo, "Ahn Group Handles" - Prishtina, “Ramtech� - Zagreb, “Silkapor� – Kosovo, etc, and results obtained are presented in this paper.

At the present time subsurface brines are the dominating raw material for lithium carbonate production worldwide because of lower production costs as compared with processing costs for lithium ores and other lithium-bearing raw materials. However, due to rising demand for lithium that materials appear to be economically feasible for the production of Li2CO3. In this study processes based on roasting-leaching-crystallization steps and condensation-precipitation- steps, respectively for Li2CO3 separation from spent Li/MnO2 batteries and lithium-containing wastewaters, respectively were developed and verified on a laboratory scale. Spent Li/MnO2 batteries were roasted under reduced pressure at 650°C, which split the castings and deactivated the batteries by reduction of LiMnO2 and MnO2 with residual lithium metal and graphite to form MnO and Li2CO3. The resultant lithium carbonate was selectively solubilized in water with manganese remaining in the leach residue. Li2CO3 of 99.5% purity was obtained after evaporation of 95% water. Processing of lithium-containing alkaline wastewaters from the production of liquid rubber comprises condensation up to lithium concentration of 10-12 g/l Li and two- step precipitation of lithium carbonate using CO2 as a precipitation agent. Sparingly soluble Li2CO3 was obtained in the second step at 95°C, whilst most impurities remain in the solution. Obtained lithium carbonate products contained from 98.6 to 99.7% Li2CO3 depending on the purity of processed wastewaters and lithium concentration in the original solutions.

The paper presents the results of a laboratory study aimed at verifying the possibility to use particular types of electric arc furnace (EAF) steel slags, in substitution of the natural aggregates, in the production of high performance bituminous mixtures (Stone Mastic Asphalt, wearing course and base course asphalts) for road flexible pavements, characterized by a steel slag content higher than the 89% in weight. The experimental trial has been articulated in a preliminary study of the physical-geotechnical properties of the EAF steel slag and in the following design of the asphalt mixtures, on the basis of the Marshall procedure. The performance of the asphalt mixes, in terms of stiffness and moisture susceptibility, has been investigated, through dynamic modulus tests at various frequencies and indirect tensile strength tests, for both dry and wet conditions. All the different types of bituminous mixtures have completely satisfied the requisites for acceptance in the road sector technical standards (Marshall Stability and Quotient up to 1,530 MPa and 462 daN/mm respectively, depending on the mix) thus resulting as suitable for use in the construction of road infrastructures.

The technological development seen in the last decades in the various sectors of the electronics industry has stimulated the replacement of electronic equipment. As a result, there has been a growing disposal of obsolete computers and other electronics equipment into landfill sites throughout the world. Computer monitor screens present as coating a powder containing a mixture of oxides and sulphides containing high quantity of yttrium (Y) and zinc (Zn) and other precious metals, in lower amount, but with high commercial value, such as europium (Eu), indium (In), iridium (Ir), strontium (Sr) and zirconium (Zr). Recycling of electronic waste is an important subject not only as waste treatment is concerned, but also when the recovery aspect of valuable materials is considered. This work focus on the recovery of Y, Zn, Eu and In from coating powder residue scraped from discarded computer monitor. The powder was obtained by manually scraping the inner surface of the screen. Two steps of the powder leaching were required. In the first stage of leaching, Eu, Y and large amount of Zn was leached. In the second stage, In and the remained Zn were dissolved. In the step one of leaching a liquor containing 15,5 g/L Y, 23 g/L Zn and 0,87 g/L Eu was obtained. In this step, the dissolution yield of Eu and Y was higher than 97 w/t%, while the dissolution of Zn was around 93 wt%. In the second step of leaching the dissolution of In and Zn was 95 and 99w/t%, respectively. After the leaching step, the metals were separated and purified by solvent extraction. DEHPA was used as extractant, sulphuric acid was used as scrubbing agent for Eu and as stripping agent for Zn and In, while hydrochloride acid was used as Y stripping solution.

With the increase in environmental awareness, disposal of any form of hazardous waste has become a great threat to the industrial sectors. During desulphurization of petroleum product, there is generation of a huge quantity of hydro-refining spent catalyst. This catalyst consists of an appreciable amount of molybdenum metal and sulphur as well. When disposed to the environment, it pollutes the air as well as ground water levels. Keeping in view the above, lime-enhanced carbothermic reduction has been proposed to be carried out for this spent catalyst. The effect of various experimental parameters on the recovery of molybednum has been discussed in this paper.

The management of Mechanical Biological Treatment reject (MBTr) is today a significant problem in several countries due to the large quantity of material sent to landfill. This product is composed mainly by glass, especially packaging glass. In Portugal, for instance, there are 5 MBT plants in operation and 7 to be commissioned in the next year. It is estimated that about 75000ton/year of glass from MBT-r will be landfilled. When MBT is correctly operated the non organic residue is composed mostly by mineral type materials such as stones and anthropogenic inert materials, like glass and ceramics, with particle size under 20 mm. The recycling of glass obliges its separation from the other materials. Optical sorting, currently used in the sorting of the packaging glass disposed by citizens in glass containers and bottle banks, has not been an option to be applied directly in MBTr for the process efficiency decreases drastically with particle size and it is very sensitive to feed composition and organic contamination. The present paper describes the experimental work carried in the search for economic and technological solutions for the recovery of the glass contained in the MBTr that could significantly contribute to the “closed loop recycling�. A thorough experimental work was carried out by testing different processes applied before optical sorting. Separation methods commonly used in mineral processing, like screening, were used. The apparent difference in the shape of glass particles (flaky particles) and other material particles (mostly sub-spherical particles), mainly in the upper size range, were exploited applying gravity concentration. Pre-processing by washing and drying was tested too. The optical sorting efficiency was evaluated and its limitations were related with particle size, feed composition and organic contamination.

Electrical and electronic equipment (EEE) represent today a huge amount of wastes which have to be managed according to the highest environmental standards and economic requirements. While in Europe, in average, 4kg of waste from EEE are produced each year per inhabitant, in Portugal this value increases to 4.7, which represented 45 000tons in 2009, 30% of the EEE commercialized in that year. The management of this stream of waste, specially its processing and valorization of materials, is today a challenge due to multiple problems. One major problem is the heterogeneity associated and the large amount of types of materials, namely polymers. In the lecture, firstly, the characterization of waste from EEE is addressed; The special topics of sampling and material analysis are discussed. Then, the problems related with materials separation are dealt with. Current practice and some case studies are presented as well as the new developments in the subject.

The paper discusses an experimental analysis concerning cement bound mixtures for road foundations, with an aggregate matrix completely composed by industrial wastes, as foundry sands, electric arc furnace (EAF) steel slags and bottom ash from municipal solid waste incineration (MSWI), combined with different dosages. The research involved a preliminary study of the physical-geotechnical properties of the three different industrial wastes, and a subsequent mechanical characterization of the cement bound mixtures. The mix design has been conducted in terms of Proctor, compression and indirect tensile tests. At the end of the study the dynamic elastic modulus of the mixtures was determined by means of ultrasonic tests, also at different curing periods. The results were completely satisfactory for all the mixtures designed, especially for that characterized by 30% foundry sand, 30% bottom ash and 40% steel slag, which attained 7 days compression strength up to 4.18 MPa and indirect tensile strength up to 0.39 MPa. The experimental results met the main Italian Specifications, so demonstrating the feasibility of using industrial by-products as integral substitutes of the conventional natural aggregates in the production of cement bound granular materials for road foundations.

Recycling of aluminium scrap and white dross yields significant economic and energy savings, as well as environmental benefits. During the smelting process of recycled aluminium scraps fluxes consisting of NaCl and KCl are added on the molten bath to prevent metal oxidation and remove impurities from the charge, and thus black dross is formed. Black dross contains water-soluble compounds which may react with water or environmental humidity and release chlorides into the water and/or give off noxious gases (H2, CH4, NH3 and H2S). After the salt has been removed from the black dross it is considered to be non-hazardous, and can safely be landfilled. Black dross does also contain many relatively valuable compounds that may be worth recovering, i. E. Alumina (Al2O3) and spinel (MgO-Al2O3). The aim of the present work is to experimentally investigate the salt removal from black dross by heat treatment under different conditions. The first and second part of the study covers heat treatment of secondary aluminium dross in an inductive furnace, and the third part in a rotary furnace to enhance stirring. In all cases the chemical composition of the black dross after heat treatment were investigated by SEM-EDS and XRD analyses. In the present study it was established that the salt contained in the black dross, i. E. 35wt%, starts to evaporate at approximately 1273 K in an inert atmosphere (argon), as well as in vacuum. The salt removal efficiency was found to increase in both cases as a function of temperature. When conducting the experiments in a vertical induction furnace in an atmosphere of argon, the highest salt removal efficiency was obtained after heat treatment of a 20 g sample for 10 hours at 1573K. A residual salt amount containing 0.33wt% chloride was obtained in this case. By sucking vacuum simultaneously as argon gas was introduced into the system lowered the chloride concentration in the residue to 0.2wt% when heat treated at 1473 K for 8 hours, and to 0.095wt% when heat treated at 1523 K for 10 hours. The improvement obtained by increasing the temperature by 50 K may, however, not be justified from an economical view point. When conducting the experiments in a rotary furnace in an atmosphere of argon it was, due to the enhanced stirring, possible to increase the sample size from 20 g to 750 g, and still reach results that were in good agreement with the results obtained in the induction furnace. It was also established in the present study that at temperatures above 1273 K the aluminium nitride present in the melt were partly oxidized to alumina, as well as to spinal. Based on the present results it is concluded that the optimum conditions for salt removal from black dross by heat treatment is in an atmosphere of argon in a rotary furnace.

Sustainable development requires the optimal use and recycling of the natural resources and wastes respectively. Recycling is the final productive use of end-of–life vehicles (ELVs), obsolete appliances, as well as industrial and municipal wastes. Wastes have become an important source for production of iron and steels, aluminium, copper, and other metals, as well as composites. Shredding and recycling plants are built to first shred the obsolete goods in pieces and then process the mixed scrap to recycle different metals and non-metals fractions for metallurgical and other industrial uses. Currently, the rate of recovery for obsolete goods in shredding and recycling plants, around the world, approximates to 75-80% and about 20-25% of the feed to the shredding and recycling plants is land-filled. However, social and economical concerns and new legislations together with the depletion of natural resources dictate for improving the recycling rate in an environmentally sound and economically viable manner. The new legislations for recycling rate of End of Life Vehicles (ELVs) and other obsoletes, especially in Europe, do not allow for such low recycling rate. The shredding plant facilities and their performances and possibilities for improving the quality and quantity of recycled products and protect environment through different scenarios are discussed. Furthermore, a case study for the result of improving the quality of ferrous scrap for metallurgical application in Sweden is presented.

The solid wastes resulting from the physical, chemical and biological treatment of used solutions from metal coating processes are termed as metal finishing sludges or metal hydroxide sludges. These wastes are generally of inorganic character and contain high levels of heavy metals and anions. Metal finishing sludges are considered as “hazardous waste� in many countries and are disposed of at sites designed specifically for hazardous wastes. Cadmium, copper, lead, nickel and zinc are the most widely studied heavy metals in metal finishing sludges and are on the list of priority pollutants compiled by the United States Environmental Protection Agency (US EPA). Solidification is one of the remediation processes, in which waste materials are mixed with various binding media to obtain a new product with improved physical properties. Immobilization within a cement-matrix does not require expensive thermal treatments to render hazardous waste inert and in a stable form. The final product is resistant to aggressive environmental agents and can be safely stored in landfill sites. In order to evaluate the possibility of soil and water contamination during the storage, leachability tests of the solidified waste have to be performed. In this study, we aimed to reduce the contamination of high level heavy metal pollution by using the solidification/stabilization (S/S) method with different additive materials and cement. Leaching potential of metal ions after S/S procedure was evaluated by two different leaching tests, toxicity characteristic leaching procedure (TCLP) and DIN 38414 methods by using acetic acid solution and water, respectively. Leaching tests were performed in a shaker during 18 h and 24 h, respectively. The concentrations of heavy metals in liquid extracts were measured by Flame Atomic Absorption Spectrometry (FAAS). Cement based S/S process techniques using different construction and insulation additives can be effectively applied in order to sufficiently treat these metal hydroxide sludges containing heavy metals.

Slags are essential in high temperature metallurgical processing to purify molten metal at competitive prices. Large volumes are produced annually, leading to important economical and ecological issues regarding their afterlife. To maximise the recycling potential, slag processing has become an integral part of the valorisation chain. Stainless steel slags present a fascinating case. During the melting and decarburization processes the chromium content of the slag is a major metallurgical factor. The cooled and treated slag can for instance be used as an aggregate in road construction. In this paper some of the past and present work on stainless steel slags will be highlighted: Chromium recovery in the EAF process; Boron stabilisation and distribution in slags; And slag microstructure development during solidification. Relationships between the metallurgical process requirements, hot stag slag processing and utilization potentiality of the slag will be discussed. It will be shown that control of the slag ‘microstructure’ during metallurgical processing and in the cooled product are essential both to metallurgical process optimisation and slag valorisation.

Kroll process is a well-known extraction process which produces titanium. It consists of 4 steps containing chlorination, reduction, vacuum distillation, electrolysis. Electrolysis process is not directly related to production of metal titanium, but it has an important role being recycling of by-product, magnesium chloride. During this electrolysis process, metal magnesium is oxidized at cathode and chloride gas is reduced at anode. Chloride in forms of bubble makes various flows in the molten magnesium electrolytic cell. Flow is a significant factor that determines efficiency of process. Therefore, a three-dimensional mathematical model was developed to investigate the flow of the molten magnesium salt, and validated against data of pilot scale experiment. The model predicted the flow field with applying change of variable such as cell temperature, distance between electrodes, and design of electrode. And operating parameters which optimize the electrolysis process was suggested by simulation for productivity and cost savings.

Korpa, A., Xhaxhiu, KFaculty of Natural Sciences, Blv. “Zog I�, 1001, Tirana, AlbaniaIn line with the goal of sustainable development in the construction industry, we have investigated the possibility of developing clinker free binders (cements), at low energy cost, composed of ground granulated blast furnace slag with addition of various activators. Several blast furnance slags obtained from different sources as well as a large number of common and new activator types were tested. It shows that, the granulation process is of major importance for the quality and suitability of the slag for the binder production. The reactivity of blast furnace slag depends on its chemical and mineralogical composition, on the degree of vitrification and fineness of grinding, more precisely on the particle size distribution and specific surface area. The properties of the resulting binders were strongly dependent on both slag and activator characteristics. In order to assess the influence of the activator concentration on binder properties (setting time and strength), the activatiors were employed with varying concentrations. The slag-sulphatic type activators show worse resulting binder properties then the slag alkaline type activators. However the mixture of sulphatic-alkaline activators due to the synergitic activation effects produced binders of optimal properties. The optimisation to obtain high quality cements for industrial applications can be performed either through the binder, slag or both at the same time.

With a current global production of approx. 260 Mton/a and an average annual growth rate of around 10 %, plastics belong to the largest and fastest growing raw material streams. Due to the low density of plastics, global production has even surpassed steel making in terms of metric volume. The high level of plastics consumption results in corresponding amounts of waste plastics, a substantial part of which is currently used as a secondary fuel or reduction agent in materials processing, such as cement production, steel making and non-ferrous metallurgy. The current secondary fuel market relying on plastics waste is rather immature and is dominated by short-term goals. Suppliers and users in this market have limited insight in each others true requirements and synergy opportunities. Impurities in secondary fuels, such as heavy metals and halogens, are often used for price negotiations, while synergy or true environmental benefits are rarely considered. For example, zinc-containing car tyres are often sold to cement kilns, where the zinc content is lost into the cement, instead of recovering it via a suitable metallurgical route. The widely recognized need for sustainability calls for a more structured use of waste plastics as well as a closer and long-term co-operation between suppliers and end users of secondary fuels. This paper attempts to give an overview of major plastics waste streams categorized by their suitability for use as a secondary fuel or reduction agent. It is pointed out that at least from a sustainability point of view, recycling is preferred for waste streams with a fair potential for material recovery. On the other hand, numerous arguments advocate for the use of mixed waste streams of glass fibre reinforced and mineral filled plastics as a secondary fuel or reducing agent. The role of metals, halogens and other elements used as an additive in plastics are dealt with in this context. Opportunities to arrive at a more sustainable use of waste plastics in metallurgy and materials processing are discussed.

The paper presents few aspects concerning of the new alternative iron making technologies in Romania. A few reasons are analyzed for the apparition and development of such technologies in the world steel market competition. The presence of altenative iron making technologies will be a benefit for metallurgic, economic, social and environmental reasons. The preliminary researches made using wastes from chemical and metallurgical industries are encouraging for developing alternative iron making pilot plants

A salt extraction process was applied to chromium oxide to recover metallic chromium. This process consists of two steps: 1. Dissolution of chromium oxide into the molten salt mixture; 2. Electrolysis of salt phase to recover Cr as cathode deposit. In dissolution step Cr2O3 powder was dissolved in a mixture of KCl, LiCl, NaCl and AlCl3 in which aluminium chloride is the main dissolving agent. However, due to high vapour pressure, the yield of AlCl3 is low as a considerable amount of it evaporates before reacting with Cr2O3. Therefore, to increase the yield of AlCl3, in this work an additive containing 30 wt. % AlCl3 was prepared at a low temperature (450-500áµ’C). The effect of replacing pure AlCl3 by this additive was studied in two series of dissolution experiments. Chemical analysis of dissolution samples by ICP-AES shows that using this AlCl3 additive minimises the loss of AlCl3 and the efficiency of the process is significantly increased. After dissolution period the attained salt bath was electrolysed under an applied voltage of 2.8 V. The cathode deposit was subjected to SEM/EDS and XRD analyses, which confirmed the formation of Cr. The results show that molten salt extraction process offers a promising route towards the extraction of metallic chromium from its oxide.

With the intention of preserving the environment and material resources, a great deal of efforts has been dedicated to the recycling and reutilization of a wide variety of materials, by frequently targeting the production of advanced materials. This has stimulated the development of new recycling technologies which require not only financial and human resources but also new facilities and equipments including efforts to publish many scientific papers or file new patents. However, at some point, the amount of efforts devoted to develop recycling technologies has to be balanced with the one employed in the production of a given material in the first place. This is because there is a risk of contamination or causing more damage during recycling compared to the original production. While the recovery and recycling process of various materials may vary due to different end-point applications one thing that may apply to all of them is the central paradigm of materials science and engineering relationship: “Processing  Structure  Property  Performance�. In this paper in order to achieve the attainment of full existing potentials the above paradigm is applied in the new reality of recycling necessity. As such a new modified paradigm is proposed that includes recyclability in the close-cycled relationship expressed as “Processing  Structure  Property  Performance ->Recyclability�. If in the development of any technology for the production of a new specific material the recyclability of the final products is taken into consideration as an additional criteria, the efficiency of the overall technological process will be much higher. As a consequence it can also be postulated that the same pivotal role can be equally played during the production of a given material for the first time as well as during its reutilization or recycling. In this point of view the production and reutilization of some materials are analyzed and owing to their technological and economical importance some typical examples are discussed. An outlook in which utilization, reutilization and recycling are organic part of the new modified central paradigm linked together in a closed cycled is presented in the conclusions.

Steel slag is main by-product in steel making process, and how to utilize it as resource has been an urgent issue for metallurgy industry. Until now, large-scale utilization of steel slag is not realized, since the limitation of its quality for potential application. China is the largest producer of crude steel, with the result that production of steel slag is also massive. Thus, development of high efficient and high value-added technology of steel slag utilization in China is of great significance for growth of recycling economy and increasing availability of resources in metallurgical industry. The converter slag was chosen as raw material with several other clay materials, and formulas of CaO-A12O3-SiO2 system and CaO-MgO-SiO2 system were designed. Steel slag based ceramic material of stable properties was processed successfully. The ceramic material of CaO-MgO-SiO2 system has a better performance, and the highest bending strength of the samples was up to 99.84MPa. The microstructure of these ceramic samples was analyzed by SEM, EPMA and XRD. It is found that the crystal phase composition of the samples which were made from the same formula system was similar. For CaO-A12O3-SiO2 system, the main phases of the samples include quartz, anorthite and pyroxene. While for CaO-MgO-SiO2 system, the main phases are diopside and diopside ferroan when the steel slag addition amount reaches 40% (mass percent)， however，the main phases are akermanite and enstatite when the steel slag addition amount is over 65% (mass percent). In addition, since the diopside was observed as short-column-like or needle-like structure, it is assumed to act as the frame of the ceramic material, which may contribute to the high bending strength tested. The results of this study indicate that the idea of making ceramics from steel slag provides a new technical route for the utilization of steel slag as resource, and the processing method can be a promising technology for future high value-added utilization of steel slag.

Dismantling of Cathode Ray Tubes (CRTs) represents a pressing environmental problem. Dismantled CRTs are generally used in the production of new CRTs in close-circuit recycling scheme, but CRT technology is becoming obsolete, due to the technological changes towards flat panels so new applications must be found. On the other hand, new legislation, such as the European Directive on Waste Electric and Electronic Equipment (WEEE), will require increased recycling and recovery rate, while landfilling should be more and more a residual option. Due to the particular composition of CRTs glasses (funnel and panel, welded together with a lead frit), in-depth investigations need to evaluate the feasibility of open-circuit recycling scheme, considering technical features, quantities, environmental implications and economic considerations. In this study, an experimental process for CRT glass recycling has been tested to obtain a product able to meet the required market standard. After a mechanical comminution process at industrial scale on CRTs glasses, consisting of an attrition operation controlled by a screening unit, the obtained glass cullets have been utilised in a thermal process at laboratory scale to produce a porous glass suitable for structural and insulating applications in building constructions, using calcium carbonate as foaming agent. Different operative conditions have been tested, varying process temperature and concentration of the foaming agent. The shape of pores and the properties of porous glass obtained have been investigated by image and mechanical analysis, in order to set up the proper operative conditions.

HyperSpectral Imaging (HSI) is based on the utilization of an integrated hardware and software (HW&SW) platform embedding conventional imaging and spectroscopy to obtain both spatial and spectral information from an object. Although HSI was originally developed for remote sensing, it has recently emerged as a powerful process analytical tool, for non-destructive analysis, in many research and industrial sectors. The possibility to apply HSI based techniques in order to develop innovative on-line sorting strategies for different materials in recycling processes and/or to define new process and quality control logics in different recycling sectors is presented and critically evaluated. The HSI based logics can be profitably applied in order to design and implement fast, reliable and low-cost strategies for: I) quality control of recycled materials that must comply with specific chemical and physical constraints, ii) performance evaluation related to the processing chains and/or real-time tuning of operative variables and iii) classification-sorting actions addressed to recognize and separate different recycled products. Case studies, related to recent advances in the application of HSI to different industrial recycling sectors, as plastic, glass, fluff, bottom ash and compost, and addressed to specific goals as contaminant detection, constituent analysis and quality evaluation are described, according to authors' originally developed application.

Phosphorus is a vital component of every cell in all living organisms. No other element can replace phosphorus as a primary nutrient that is essential for plant growth. Plants take up phosphorus from soil. Plant available phosphorus pool in soils needs to be replenished by spraying phosphorus fertilizers. Limited natural resources, phosphate ores, predominantly concentrated in Morocco, China and USA, are going gradually into depletion. 159 million tons of phosphates have been mined 2009. Drivers for phosphate consumption are available cropland, growth of population, changing diets and bio-fuels. Sales shall grow by 2-3% per year. Renewable phosphates from sewage sludge and slaughterhouse residues can replace up to 40% of the natural rock phosphates. After widespread and constantly increasing energy recovery in more than 400 sludge incinerators, these materials produce 3 million tons of ash with a phosphate concentration of up to 30%, being available as a waste at negative cost. Without treatment, ash is not a fertilizer because of its high heavy metal concentration and deficient phosphate plant availability. Because of an increasing concern with nutrition safety, food manufacturers and policy makers prefer energy recovery from sewage sludge opposed to its direct application as a fertilizer on cropland, the vanishing alternative phosphate recovery route. In Europe, landfill disposal of sludge is not a legal option any more. ASH DEC has developed a thermochemical process to eliminate heavy metals from ash and simultaneously make nutrients plant available. For this purpose, a mix of phosphorus rich ash and – predominantly - magnesium salts is fired at 1.000°C in a reactor. At this temperature, the toxic heavy metals form gaseous metal chlorides that leave the kiln with the process gas and are captured as filter dust in a dry air pollution control system. Simultaneously, within the solid phosphate compounds, magnesium ions partly replace calcium ions and significantly improve the plant availability of phosphates. The result of the thermochemical process is a phosphate fertilizer that compares to traditional superphosphates in terms of efficiency. The product’s heavy metal loads, however, are one to two orders of magnitude below those of most rock phosphate based fertilizers (cadmium, uranium) and below those of the sludge ash (cadmium, copper, lead, zinc). Before the process could be transferred to industrial scale, a process controlled 7 ton per day, pilot plant was set-up and operated for two years in Austria. Operations aimed at proof of the technical concept, process optimization and test of machinery and equipment. Operational experience and results are shown in the full paper and at the conference.

The annual production of bottom ash resulting from the incineration of municipal solid waste in Europe includes about 400,000 tons of metallic aluminum and 200,000 tons of heavy non-ferrous metals, such as copper, zinc and lead, and even traces of precious metals. The efficient recovery of this non-ferrous metal resource has been subject of several innovative research and development programs, which are now showing their results in the field. Solutions vary from improvements in state-of-the-art eddy current separation technology, to advanced dry or wet classification to remove the fine mineral fraction prior to metal separation, and even to adaptation of the incinerator itself. The paper presents a review of the various technologies in terms of costs, revenues, health issues and applications of the mineral residue. Field data show that efficient recycling has a significant impact on value recovery as well as on non-ferrous metal recycling rates, even simple measures producing 25% more metals from the ash.

Combustion residues of heavy Petroleum fuel (Mazut), containing compounds such as vanadium is valuable. Mazut widespread use of fuel in thermal power plants causes the formation of a significant ash inside the boiler, so they are worth considering and vanadium compounds, the ashes can Mazut as an important secondary source for the extraction of vanadium used such as Ferro-vanadium and ammonium metavanadat. Ferro-vanadium production are requires two steps. First phase extraction of vanadium resources to do it as vanadium oxide and other steps to revive Aluminothermic Reduction process and ultimately produce Ferro-vanadium. This study followed the procedure pyro-hydrometallurgy for the extraction of vanadium as Vanadium Pentoxide powder or Aluminothermic Reduction method for producing ammonium metavanadat selected and evaluated the factors affecting it were studied and optimum conditions for each of these processes were determined.

Waste materials produced in supplying energy, such as: Coal gob piles, oil sand residues, and oil refinery "bottoms", are converted into useful products using a three stage process. In the, patented, first stage, carbon dioxide is used as a reagent to convert the organics an active carbon and energy. The , patented, second stage uses a part of that carbon to produce sulfur and metals. In the patent applied for, third stage, the carbon is used to produce hydrocarbons inexpensively, and /or hydrogen for upgrading oil, and/ or electricity. The objective is a cleaner environment, and the production of useful products.

In the Deep Galvanizing Process the two zinc containing residues are: Zinc ash and hard zinc. The amount of produced zinc ash is approximately 13 wt. -% and of hard zinc around 12 wt. -% of the zinc input. The aim of the presented work is the recovery of the metallic zinc hard zinc by using the ceramic filtering technology. Aluminum is used as refining agent. Between 1 to 4 % weight has been added to melted hard zinc to form intermetalic phases Fex-Aly at temperatures between 450 and 550°C. Argon gas was used in the process to obtain an inert atmosphere. Absorption atomic spectroscopy, Scanning Electronic and Optical Microscopy were used to analyze the refining and liberation of Zinc form Hard Zinc. The results applying the best process parameters of laboratory scale tests are resulting in a zinc recovery of 65 % by separating the intermetallic phases from hard zinc.

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