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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...