National University of Science and Technology «MISiS» (Moscow, Russia):

P. I. Chernousov, Cand. Eng., Associate Prof., e-mail: p.chernou@yandex.ru
O. V. Golubev, Cand. Eng., Associate Prof., e-mail: olega-san@yandex.ru

Stoilenskiy Mining and Beneficiation Plant (GOK) (Staryi Oskol, Russia):
S. N. Seregin, Director of Repair Complex, e-mail: seregin_sn@nlmk.com

Currently, in Russia at the Nizhny Tagil, West Siberian and Novolipetsk metallurgical plants have been implemented projects for the introduction of pulverized coal fuel (PCF) technology. In the next decade, we should expect the expansion of the use of PCF at domestic integrated metallurgical plants, therefore the analysis of the world experience of the effective use of PCF is relevant. The main modern methods of studying the unused residue from pulverized coal blown into the blast furnace are presented, their advantages and disadvantages are considered, and the adequacy of the conditions of the blast furnace tuyere zone is analyzed for methods of physical modeling of PCF combustion. Based on the results of the study, it was concluded that vertical tube furnaces (VTF) and stream reactors (SR) most adequately reflect the conditions of the blast furnace tubercle zone. It is proposed to use a single term to denote a partially reacted PCF leaving the blast furnace with a gas – «unused coke residue of PCF» (UCR PCF). The data on the content of UCR PCF in blast furnace dust and sludge, obtained using X-ray phase analysis (XRF), is well supplemented by data on the microstructure of dust particles obtained using the Field Emission Scanning Electron Microscopy (FESEM) method. A possible option for combining the advantages of optical microscopy and XRF is the preliminary preparation of samples of UCR PCF using equipment simulating the tuyere zone and the blast furnace shaft. These samples, studied using XRF, can later be used as a reference for the identification of UCR PCF in the study of blast dust using optical microscopy. The implementation of this approach is possible, for example, in the framework of the joint work of a large research center and several metallurgical companies.

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