OPTIMISATION OF THE SLAG MODE IN THE LADLE DURING THE STEEL PROCESSING OF SECONDARY METALLURGY

Optimisation of the slag mode in the ladle with the help of briquetted fluxing agents, based on Al2O3 under various technological conditions is the object of this paper. The aim of the industrial experiments was to assess the possibility of achieving the optimum chemical composition of the slag that would improve the kinetic conditions of the refining ladle slag during the treatment in secondary metallurgy units. Industrial experiments were focused on comparing the influences of different slag-making agents such as lime (CaO), briquetted fluxing agents and deoxidation agents forming calcium carbide (CaC2) and granular aluminium (Al-granul). During the evaluation of the slag mode in the ladle, samples of the steel from different technological places under operational conditions were taken to assess the desulphurization degree. The samples of the slag for evaluating the chosen parameters, such as basicity, the content of easily reducible oxides, the proportion of CaO/Al2O3 and the Mannesmann index, were taken too. Further, the temperature and the oxygen activity in the steel were continuously measured too. The results mentioned in this paper represent the basic information about the possibilities of the slag-mode optimisation in the ladle using different proportions of the slag-making additions, briquetted fluxing agents as well as the deoxidation agents within secondary metallurgy.