Novolipetsk Steel Company (NLMK), Lipetsk, Russia:

T. V. Prokhorova, Engineer, Technology Development Department, e-mail: prohorova_tv@nlmk.com
D. A. Neugodov, Engineer, Technology Development Department
E. A. Milokhin, Head of the Iron Production Technologies Group, Technology Development Department
O. A. Semenov, Head of the Sintering Shop

The sintering process of agglomerate, its mineralogical composition and its structure are influenced by granulometric composition of solid fuel. It is considered to be, that the increasing portion of small fractions less than 0.5 mm in the structure of the agglomeration can lead to reduction of specific productivity, yield of suitable agglomerate, vertical sintering rate, deterioration of the strength characteristics of the agglomerate. The work describes the results of conducting semi-industrial and industrial experiments about removal of a fraction less than 0.5 mm from the composition of solid agglomeration fuel at the Agglomeration factory of Novolipetsk Steel Company (PJSC NLMK). It is analyzed technology of preparation solid agglomeration fuel for agglomeration in the conditions of NLMK, the degree of destruction of coke fines at all stages of its preparation for the sintering process is also estimated. The analysis of the influence of the content of –0.5 mm fraction and +3 mm fraction in the composition of solid agglomeration fuel on the technical and economic indicators of the agglomeration process in the conditions of NLMK was performed. It is revealed that during selecting the fractional composition of agglomeration fuel, its size should correspond to the size of the charge materials, and with the predominance of fine-grained materials (such as iron ore concentrate) in the composition of the agglomeration charge the fine fraction of –0.5 mm of solid agglomeration fuel during sintering does not have a noticeable negative impact on the technical and economic indicators of the sintering process, nor on the quality of the finished product. In the course of the conducted studies, there was no improvement in the parameters of the sintering process or the quality of the agglomerate with a decrease in the fraction of –0.5 mm in the composition of the solid agglomeration fuel for the existing agglomeration production at NLMK.

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