The influence of hot briquetted iron on technological, thermodynamic and economic factors in the arc steelmaking process

Abstract

In this article, the effect of hot briquetted iron (HBI) on the steel smelting process in electric arc steel smelting furnaces (EASSF) is comprehensively studied. The main focus is on the analysis of the composition of the semi-product, which is formed under conditions of changes in energy-technological parameters, the process of slag formation, the mechanisms of metal slag melting and an increased share of HBI.
It turns out that when HBI is used, the specific consumption of electricity increases, the amount of slag and the degree of oxidation of the metal–slag system increases. At the same time, the amount of carbon in the metal decreases. When the HBI share exceeds 25-30%, the likelihood of the formation of solid insoluble shlaco-metallic conglomerates under portioned loading conditions increases, which can damage the inner lining of the furnace.
A thermodynamic analysis of the phosphorus loss process has been carried out, taking into account the calculation of the distribution coefficients of phosphorus and the assessment of the equilibrium level. When HBI is used, the steel content has been found to decrease in harmful impurities (phosphorus, sulfur, nitrogen, copper, nickel, chromium, tin). This was due to the high purity of HBI raw materials and the strong oxidation of slags.
In addition, a method has been developed to estimate the amount of copper in half the product in different combinations of shikhta. This applied normal distribution functions and regression analysis. Also given is the feasibility of using HBI instead of precious metal scrap and recycled cast iron. It has been proven that using HBI through proper loading and slurry regime control can be a cost-effective and from a technological point of view acceptable solution.