Research on the failure mechanism of blast furnace tuyere based on experiment and numerical simulation results

The tuyere, an integral component of a blast furnace, plays a vital role in conveying energy and ensuring stable furnace operation. Given the tuyere's exposure to a complex working environment within the blast furnace, it is prone to breakage and failure. Thus, investigating the causes of tuyere failure is crucial. This study employs computational fluid dynamics alongside experimental characterization to conduct a numerical simulation of the blast furnace tuyere. The research focuses on comparing the velocity and temperature fields of the tuyere under various cooling conditions to analyze the reasons behind its breakage. The findings reveal that the accumulation of alkali metal elements such as Zn, K, and Na on the tuyere's surface significantly hampers its longevity. Moreover, the cooling water's flow rate, inlet temperature, and scale thickness emerge as critical factors influencing the tuyere's cooling efficiency. Notably, each increase of 30 L/min in the inlet flow rate results in a decrease of approximately 3-5 K in the tuyere's maximum temperature. For every 2 K rise in the inlet water temperature, the tuyere's maximum temperature increases by 2-3 K. Furthermore, an exponential increase in the tuyere's maximum temperature is observed with each 0.1 mm increment in scale thickness. When the scale thickness reaches 0.4 mm, the tuyere's maximum temperature rises to 545.07 K, an increase of 18.49 %. Thus, this study offers novel insights into the causative factors of tuyere failure, contributing significantly to the efficient utilization of energy within the blast furnace and the optimization of the production process.