Diameter Selection of Blast Furnace Tuyeres Based on the Rate and Energy of the Fuel-Enriched Blast and Tuyere Gas Flows with the Injection of the Pulverized Coal

The diameter of the air tuyeres on the blast furnace must be selected not based on the change in the kinetic energy of the fuel-enriched blast flow, but in order to not lose the blast flow rate, especially with weak blowing compressors, to ensure its growth. In this case, it is imperative to keep the optimal total mechanical energies of the fuel-enriched blast and tuyere gas flows on the furnace, which determine the change in the size of the combustion zones and the penetration depth of the gas flow to the hearth center of the blast furnace. Optimum energy values are set by calculation during periods of high-performance furnace operation with low coke consumption. The diameter choice of the tuyeres in terms of kinetic energy leads to errors in the distribution of the gas flow “from the top”, especially when switching from the technology of natural gas injection to the technology of injection of pulverized coal. Attempts to regulate the gas flow “from the bottom” when the pulverized coal is injected by the “top” control methods do not always give a positive result.