Effect of the Surface Relief of the Heat-Insulating Insert in the Blast Channel of Blast-Furnace Tuyere on Its Efficiency

• Published in: Metallurgist (New York) Vol. 67; no. 3-4; pp. 354 - 361
• Main Authors: Albul, S. V., Kobelev, O. A., Levitskii, I. A.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-07-2023; Springer; Springer Nature B.V
• Subjects: Blast furnace gas; Burnout; CAD; Carbon dioxide; Carbon dioxide concentration; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Combustion; Computer aided design; Efficiency; Enthalpy; Explosions; Grooves; Materials Science; Metallic Materials; Natural gas; Thermal stress; Tuyeres; Ansys modeling; blast furnace; groove; natural gas combustion; air tuyere; blast channel; thermal stress; heat transfer; ceramic insert
• ISSN: 0026-0894; 1573-8892
• DOI: 10.1007/s11015-023-01522-3

When supplying natural gas to a blast-furnace tuyere, it is necessary to strive to increase the efficiency of the combustion of natural gas in the blast channel of the tuyere on the one hand and to protect the inner shell of the tuyere against burnout on the other hand. One of the methods to achieve both of these contradictory goals is to install a heat-insulating ceramic insert in the blast channel. We consider the possibility of increasing the efficiency of the ceramic insert by making one or more annular grooves on its surface to improve the mixing between natural gas and blast air for more efficient combustion. Ansys 21.1 software is used to simulate the motion of fluids, heat transfer, and combustion of natural gas in the blast channel with a ceramic insert that has annular grooves of quadrangular cross-section. The influence of the depth and width of grooves and the distance between them on the processes in the tuyere is studied. It is shown that an annular groove in the insert increases the total heat from the combustion of natural gas, which is confirmed by an increase in the concentration of CO
2
and the temperature and rate of blast at the outlet of the tuyere. The maximum thermal stresses in the insert increase as well, exceeding the maximum stresses in the insert without grooves by no more than 30%.