Measures have been undertaken to improve the protection of the environment in Bulgaria. Legislative changes have been made in order to bring gradually the environmental standards of the country in correspondence to EU norms. In this respect, it is of great importance to reduce the environmental loading by developing effective processes for the recycling of metal-containing wastes generated by the national industry. In this paper, the occurrence, gathering and storage of some metal-containing wastes which have not been recycled in Bulgaria is discussed and a pilot-plant unit for their utilisation is presented. The recycling of the wastes is carried out in a newly-developed Direct Current Electric Arc Furnace which has a maximum power of 500 kW and a capacity of 1.0 t iron-based melt. The main characteristics of the furnace and its lay-out are given. Experimental results obtained from the treatment of lead blast furnace slags, Zn cake from neutral leaching, EAF steelmaking dusts and spent NiCd batteries are discussed. The use of the DCEAF recycling process is analysed from the viewpoint of metallurgical technology, ecology and economics. It is shown that the high recovery of valuable metals such as Zn, Pb and Ni, the low investment and operation costs, as well as the generation of harmless by-products are particular advantages of this equipment for the emerging recycling industry in Bulgaria.
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