Analytical and experimental study of the thermophysical properties of blast furnace slag melts in the conditions of blast furnaces of Ukraine

Abstract

The aim of the work is to establish patterns of influence of the chemical composition of blast-furnace slags on the thermophysical properties of their melts, which is relevant to ensure high technical and economic indicators of the blast furnace. Experimental studies of the temperature of molten iron and slag at their release from a blast furnace with a volume of 1500 m3 have been carried out. It is shown that the temperatures of iron and slag have almost identical values and vary in the range of 1451÷14870С. On a Anton Paar rotary rheometer, viscosity measurements were made in the temperature range of 1320 ÷ 15000С and it was shown that the viscosity of slags from the blast furnace output exceeds its optimal value of 0.3 Pa.second. Based on the correlation-regression analysis of the literature data and the performed experimental studies, the enthalpy of the melts was determined as a function of the chemical composition of blast-furnace slags, which are represented through stoichiometry (ρ) and temperature. It is shown that when temperature fluctuations of slag melts in the range of 1453 ÷ 14870С their enthalpy changes in the range of 1933÷2031 kJ/kg. A predictive model for calculating the enthalpy of blast-furnace slags is proposed. On the basis of the proposed predictive model, the enthalpy of blast furnace slags for a blast furnace with a volume of 1500 m3 was calculated taking into account their actual temperatures at the outlet.