Desulphurization of Ferronickel in the converters with oxygen is the most complex part of the technological process in the Drenas foundry. Sulphur in the ferronickel melting is mostly in the form of FeS, with a melting temperature of 1195oC, and it has tendency to dissolve indefinitely in liquid iron. Our objective is to determine the sulphur removal coefficient, as a key indicator of the desulphurization efficiency in the converter, by measuring the activity and concentration of sulphur and other elements in liquid Fe and melting. Determination of this coefficient is done according to the analytical method, while comparing the current process parameters with those of the new desulfurization methods, other indicators of the refining process are determined. The refining process and the effective conduct of the study depend on the XRD analysis database of metal and slag, and as well of the technological refining process analysis data. Research has shown that desulfurization efficiency is a function of the sulphur removal coefficient, respectively; metal composition, slag, oxygen activity, CaO/SiO2 ratio, sulphide capacity, fluidity, surface pressure, etc.). In addition to this coefficient, other indicators of refining process optimization are defined.

Purpose. The purpose of the research is to substantiate the possibility of replacing existing MgO bricks with the MgO-C bricks due to their resistance to the slag aggressiveness of the electric furnace and the Si content in the resulting metal, which can have a positive effect on reducing the consumption of refractory materials. Methods. This research will be presented as the results of theoretical and experimental data determining the dependence of the electric furnace on the type of refractory material, walls construction, operating parameters and the electric furnace lining, that are expected to have a major impact on the cost output of production process. Findings. Based on the presented results, it has been revealed that MgO-C bricks are more effective in terms of preventing the furnace damage depending on refractory materials. Therefore, to optimize the production process, it is recommended to improve the composition of melted metal and slag, as well as to strengthen the control of the process parameters. Originality. Laboratory analyses are conducted in specialized laboratories, and the presented data have been obtained through the use of devices and equipment required for experimental research. Practical implications. The refractory materials are one of the main indicators of technical performance and production costs at NewCo Ferronickel in Kosovo. Therefore, the higher performance of the refractory lining will have a positive effect on the furnace durability and the quality of the final product.

The aim of this paper is based in analyze of the zinc sulphate solution obtained from neutral leaching process of zinc calcine in "Trepca" and its purification from impurities. This solution besides zinc contains also and other impurities such as (Cu, Cd, Co, Ni, As, Ge, Sb, Se, Te, Ag etc.), which are with different concentrations. The sulphate solution can released from metal impurities based on the fact that they have higher electro -chemical potential than zinc and, as such, during the refining process they separate and precipitate in metallic form. Treatment of solution with appropriate technological methods technologically is very important in continuation of the electrolysis process and is accompanied by economic effects, because of non-ferrous and rare metals benefit. In this paper are described the phases of the purification process including acidic purification, cooling, needed materials and equipments for the refining process. Also, special attention is dedicated to the factors that have influence in the process development such as concentration, temperature, time, compressed air, etc.

Purpose.The aim of our research consists in argumentation of the possibility of transformation of slag from potential pollutants into a new material used and its promotion as an alternative raw material for the production of consumable layers of asphalt concrete for highway. Methodology.The research on the possibility of using the slag of the electric furnace in Ferronickel Foundery is based on the practice of CISRO and Sumitomo Metals Industri in Japan, while the products of this process, in accordance with the standards EN12697-1:2006, EN12697-23, EN12697-12, EN 12697-27 dhe DD226-26/2004, have been used as aggregates for the production of asphalt concrete in the AHN Group-Kosovo. Findings.This paper presents the results from a study program related to minimizing the pollution impact of Fe-Ni slag landfill in Drenas, through valorization and improvement of physical-mechanical properties of slag according to the method of integrated dry granulation and using it afterwards as aggregate for the production of AC11 surf. Originality.Laboratory analyses were conducted in specialized laboratory and data presented are achieved through the use of devices and equipment that are necessary for experimental research, thus the obtained results are original data presented in this paper. Practical value.From the research data it has been proved that the conversion of Fe-Ni slag from wastes with high pollutant potentials into aggregates valuable for industry would express significant economic and environmental effects.

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