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In process of pig iron production besides main product, pig iron, also secondary products are formed, that have character of secondary raw materials and industrial wastes. The most abundant secondary product originating in the process of pig iron production, is blast furnace slag, its occurrence is about 300 to 500 kg for one ton of pig iron. Blast furnace slag originates from melting of gangue parts of metal bearing materials, slag forming additions and coke ash. Its chemical, mineralogical and physical – chemi...

The aim of this work is the optimization of sinter-crystallization regime of a glassceramic from a municipal solid waste incineratior (MSWI) bottom ash. The parent waste was melted at 1400oC, milled below 75 $\mu$m and the obtained glass powders were pressed at 100 MPa. The optimal temperature for sinter-crystallization was estimated by DTA, dilatometry and XRD. Subsequently, the degrees of sintering, obtained at different heating rates (between 2 and 40oC/min) and 1 h step at 950oC were estimated by the linear sh...

A detailed investigation of physical and chemical properties of pyrite cinders from sulfuric acid production has been carried out by employing variety of analytical methods and techniques, including ICP-MS, XRL, XRD, M\"ossbauer Spectroscopy, SEM-EDX, SQUID, TGA, etc. The study is focused on the investigation of the content and distribution of about 50 micro- and trace elements in magnetically separated fractions, and among/within individual particles. It has been found that many heavy metals exist in easily avail...

Fly dusts creates by steel and cast iron melting. Their properties depends on a type of melting aggregate. For steel it is first of all a fly dust from electric arc furnace, its chemical composition is depended on the kind of produced steel. A cupola furnace is the most used furnace for cast iron production. Fly dusts from steel and cast iron production contain some part of FeO that is reducible in a cupola and blast furnace. It is a very fine material and it has to be pelletized or briquetted before its next use....

Perspective conception is characterized by including of wastes assembly problems in sphere of general actions for environment protection taking into account as any nonvalorized waste or least non-used, pollute the environment. Processing of solid minerals sterile and obtaining of sub-products which are economically usable has major importance, both from economical and ecological point of view, through environment protection. Researches had followed elaboration of ecological technologies of processing the waste as ...

Foundries produce metal castings from ferrous or non-ferrous alloys and they operate in various locations around the world. A typical foundry workplace is composed of furnace area, pouring area, core making area, shaking out area and fettling area. The manufacturing process involves the melting of metal into a liquid, the pouring of molten metal into a cast, the removing of casting and the cleaning / finishing of the cast piece. Dusts arise almost in every of these steps of foundry processes. Solid waste streams f...

This paper presents the results obtained by utilization of pulverized coal fly ash both as raw mix component for Portland cement clinker and as admixture to cement type CEM II/B-V, too. The fly ash was analyzed from point of view of chemical, mineralogical and of radioactivity content. Two samples of raw mixes were prepared, one with raw materials as a reference sample consisting from limestone, clay, sand and pyrite cinder, and another with 10.14\% fly ash instead of clay. Raw mixes were ground at a fineness expr...

Returnable and non-returnable losses rise during melting and casting of molten metal. Non – returnable losses arise by melting and metallurgical treatment of molten metal as a back wash of evaporation, chemical reactions between molten metal and refractory lining, molten metal and air and between molten metal and refining additions. Value of these losses depends on the kind of alloy, on used furnace and charge quality. Except non-returnable losses, the returnable losses creates by melting. They represent a diffe...

The aim of the present research work is to investigate the possibility of adding a mixture of non-granulated blast furnace slag (NGBFS) and steel slag, two wastes resulting from metallurgical industry which underwent calcinations previously, in the raw meal for the production of Portland eco-cement clinker. For this purpose, the NGBFS and steel slag from ArcelorMitall Steel Galati were analyzed for chemical, mineralogical and heavy metals contents. Two samples of raw mixes were prepared, one with typically raw mat...

The possibility to obtain new eco-compatible building materials by milling, pressing and direct sintering of secondary raw materials (SRM) derived from a physical/mechanical treatment of municipal solid waste incinerator (MSWI) bottom ashes is discussed. The chemical compositions and particle size distribution of used SRM press powders were evaluated using XRF analysis and by laser granulometer, respectively. The thermal and densification behaviours were studied by non-isothermal DTA-TG and dilatometric techniques...

The University of Missouri-Kansas City (UMKC), a state-supported higher education institution, is located in a large metropolitan area in the central United States. In order to evaluate students’ attitude toward recycling and environmental sustainability, a waste audit along with a survey was conducted at three residence halls at UMKC in fall of 2009 as part of a term project for the “Introduction to Waste Management” class. The residence halls were audited by student teams that physically sorted all solid w...

The concept of “sustainability” was developed in recent years in order to make decisions under the consideration of environment. Additionally, “environmental sustainability” means the ensuring of the continuity of the natural resources most of which faced with exhaustion with the increasing population and developing technology on the world. Increasing both adaptive reuse applications and the use of alternating materials will support the protection of natural resources and provide efficiency in terms of ene...

Recycling of metals has been becoming an attractive subject, lately due to the fact that the depleted resources, high energy consumption and harmful gases emission. Metal machining chips are recycled conventionaly which consist of melting casting. In the paper the method of direct conversion of bronze and steel chips, into finished product without melting, as an alternative way to conventional method is described. Metal chips were comminuted by mechanical milling and for the next processing the granulated chips la...

Slag are by-products by metallurgical processes. The most famous slag are blast furnace slag and steel slag. Their treatment and using are known and their using is very extensive. Cupola slag formats by cast- iron production in cupola furnace. In some countries it is used by roadway building but in Slovakia it is waste only. In some European countries it is granulated and granulation product is used in building industry. Cupola slag is after tipping from cupola furnace casted in to slag dip and put in to waste dep...

In regard to indisputable carcinogenic effects of asbestos species the European Union prohibited (from January 2005) the usage all kinds of asbestos fibres in member states. This fact resulted in replacement of asbestos by artificial mineral and synthetic fibres. In this context large demolitions are realised, frequently unnecessary and a big volume of wastes and dangerous dust is created. These are mainly hazardous wastes that require an adequate disposal. The paper offers a view of the most frequently used metho...

Dusts arise in every step of foundry process. A lot of dust create by mould sands and core sands preparation. Their composition depend on used binder. The main compound of these dusts is SiO2 and by mould sands with organic binder it is carbon too. A melting process is connected with formation of flue dust, its composition depends on charge composition. Cupola furnaces, electric arc furnaces and induction furnaces are used in foundry. The most quantity of dust is produced from cupola furnace. It is very fine-grain...

Return material consists of gating, risers and residues from cold chamber, defective castings and another residues from die casting. This material has to be degreased from the fatty and separating agents that are usually of oil origin. In common praxis the clean and contaminated material is put in to melting furnace, it is melted and new alloys are added in the form of small pieces. Within the frame of experiments the influence of contaminated return material in the charge on quality die castings was observed. The...

Lignite and other types of coal are formed as result of different chemical and biological transformations of ligneous and plant materials lacking oxygen. During the coal use for energy production , there are mineralogical remains in the form of ashes, which have different physical, chemical, mineralogical and morphological properties, which largely depend on the type of coal used, and technology in its combustion. This type of ashes is presented in thermal power plants in the form of dust or fly ash and inorganic ...

Waste disposal is the biggest humanity problem nowadays. This has been recognized worldwide and we are lucky because waste treatment is applied, at least at developed countries. On the other hand Nature is suffering a lot and biodiversity is reducing rapidly. The preservation and conservation of Nature has leaded European Union to establish the NATURA 2000 network in continuity of Ramsar Convention. In this paper the conditions and the status of the biotopes of the National Park of East Macedonia and Thrace, and p...

The treatment of natural rock, as well as construction aggregates and ornamental rock creates a great amount of residues, which are usually grain sized under 100 $\mu$m and with chemical and mineralogical composition modified due to processing. Therefore these materials have a composition with a variable content of rock, accompanied with other components as iron particles, clayey materials, flocculants, etc. These contaminants limit the application of those wastes. It is necessary therefore, the search of a proces...

The economic profitability analysis of recycling process should take into account either the minimization of costs connected with the realization of investment or maximization of the production having the costs of the production established. Nevertheless, we need to take into consideration that these costs depend on many factors. In this paper, the economic profitability of municipal waste recycling by the maximization of the production having the costs of the production established or the minimization of the cost...

In the east-coast states of Malaysia, the waste management approach being employed is landfill, but due to rapid development and lack of space for new landfills, the east-coast States in Malaysia is looking for a success recycling of solid waste programmes. Households’ awareness is considered the touchstone for the success of recycling any recycling programmes. However, this paper attempts to identify households’ awareness and opinion on recycling of solid wastes in the major town of Kelantan State which locat...

The legislative framework for the environmental protection in Romania, as a European Union member state, has carried a new approach in the management of the perimeters affected by the industrial activities. At the national level, efforts are made to implement a number of projects (e.g. ISPA [The Instrument for Structural Policies for Preaccession] – Environment) that would lead to a better administration of waste materials associated with these activities (e.g. recycling in the economic circuit or the easy reint...

Smelting of hammerable iron and its treatment in Antiquity and Medieval produced also by-product: slag. Because of small yields of iron the process produced only small amounts of slag that did not attract attention of smelter concerning its possible use. The use of slag pieces was only accidental. The paper deals with the most important processes used for treatment of blast furnace and steelmaking slags and with the most important ways of their utilization. The method of recycling of steelmaking slags, that follow...

This study has for purpose to highlight and eliminate one from problems that influence negativity for the present and future of our environment. Today the environment is a big problem no only in Albania, but everywhere in world. It is very important to save our environment, because one clean environment will say healthy people, secure future.

Industrial processes do not get full efficiency and this means that a considerable amount of wastes without economical aim and which will finish in rubbish dumps, hence promoting a large environmental impact. Modern society steer itself, towards getting a sustainable development which minimize the production of these wastes, which are also increasing its economical, environmental and social costs. This fact compels to search solutions which could avoid the generation of this kind of wastes and to get value from th...

The European foundry industry is the third largest in the world for ferrous castings and the second largest for non-ferrous ones. the annual production of castings in the enlarged European Union amounts 11.7 million tonnes of ferrous and 2.8 million tonnes of non-ferrous castings. The foundry industry is a major player in the recycling of metals. steel, cast iron and aluminium scrap is remelted into new products. The most possible negative environmental effects of foundries are related to the presence of a thermal...

The present work discusses the synthesize of sintered granite–like glass-ceramics obtained by vitrification of hazardous industrial wastes. The chemical resistance of parent wastes and glasses were classified by the toxic characteristics leaching procedure (TCLP), whereas the crystallization behaviour was evaluated by DTA and XRD. The thermal and mechanical properties of final glass-ceramics were also measured and discussed. The obtained glass-ceramics have attractive appearance, elevate chemical durability and ...

The main purpose of this work was to analyze possibilities for application of lignite byproducts- fly ash from Kosova Power Plants in other industry branches and for filling of old underground mines and see the positive impact in environmental protection. The Kosova lignite-fired power generation industry produces millions tones of fly ash each year. Only small amount of this fly ash is used, with most being considered a waste. This waste must be disposed of in an environmentally acceptable way at a cost which is ...

The feasibility to substitute feldspar raw materials in a porcelain stoneware body with waste Cathode Ray Tube (CRT) glass was investigated. Various compositions, containing different percentages of feldspars and CRT glass, were compared. The densification process was studied by non-isothermal dilatometry and the degree of sintering was evaluated by pycnometric techniques. The structure and phase composition of the final ceramics were studied by SEM and XRD, respectively. The technological parameters and the mecha...

Collection, transport, transfer, recycling and proper disposal of solid waste is an essential issue for the local authorities of large metropolitan areas. Turkey, especially in the metropolitan cities like Konya, has been combatting with the same problem, changing the institutional structure of the national policy and the necessary legislation about the solid waste management and the implementation of the recyling-recovery programs to reduce the amount of the solid waste to be disposed of at the sanitary landfills...

This paper deals with the removal of copper from Municipal Solid Waste (MSW) compost using Na2EDTA and a mixture of Na2S2O5 and Na2EDTA in the batch mode. At the end of extraction studies, for 3 hours at 1:25 solid:liquid ratio by using 0.05 M Na2EDTA, 100\% removal yield was obtained for Cu. 100\% heavy metal removal yield was obtained with 0.01 M Na2EDTA and 0.1 M Na2S2O5, at 1:6 solid:liquid ratio, for Cu in this study.