Search

In this paper, a blast furnace gas flow distribution model with variable furnace structure was founded based on CFD (computational fluid dynamics) theory, and the gas velocity distribution near the surface of the copper staves in different areas of the BF is calculated under different conditions of variational structure parameters like Bosh angle, shaft angle, and the newly proposed “equivalent Bosh angle.” Based on the calculation, the influence rule of the BF structure on the service life of copper stave and the corresponding operation measures were obtained. The result shows that the increase of the Bosh angle and the decrease of the shaft angle will incur increasing of the gas flow velocity near the surface of the copper staves, which is harmful to the cooling stave life; the variation of the equivalent Bosh angle has a most significant influence on the cooling stave life, and the increase of the equivalent Bosh angle will cause a sharp increase of the gas flow velocity, which will damage the copper staves seriously; adopting long tuyeres and minishing the equivalent Bosh angle will reduce the washing action of the gas flow and ensure the stability of slag hanging to achieve a long service life of copper staves.

Cooling effects of the cast iron cooling stave were tested with a specially designed experimental furnace under the conditions of different temperatures of 800 °C, 900 °C, 1,000 °C and 1,100 °C as well as different cooling water velocities of 0.5 m·s–1, 1.0 m·s–1, 1.5 m·s–1 and 2.0 m·s–1. Furthermore, the combined heat transfer coefficient of hot-face on cast iron cooling stave (αh−i) was calculated by heat transfer theory based on the thermal test. The calculated αh−i was then applied in temperature field simulation of cooling stave and the simulation results were compared with the experimental data. The calculation of αh−i indicates that αh−i increases rapidly as the furnace temperature increases while it increases a little as the water velocity increases. The comparison of the simulation results with the experimental data shows that the simulation results fit well with the experiment data under different furnace temperatures.