Abstract:

The safe operation of the converter waste heat boiler is affected by factors such as blowing time, excess air coefficient, flue gas velocity, etc. Among them, the excess air coefficient is most closely related to practical production. Based on the thermal calculation process of the converter waste heat boiler, a thermal calculation program was compiled, and change rules of theoretical combustion temperature, heat transfer and exhaust gas temperature were obtained based on the program when the excess air coefficient changed. To the 180 t converter waste heat boiler, under the conditions that the primary furnace gas temperature is 1 600 ℃ and gas volume composition is 90 % CO and 10 % CO₂, the result shows the theoretical combustion temperature increases by 286.1 ℃, the proportion of CO in flue gas decreases from 72.468 % to 41.052 %, the heat transfer increases significantly, and the exhaust gas temperature increases by 139.12 ℃ as the excess air coefficient increases from 0.08 to 0.3.

Key words: converter waste heat boiler, excess air coefficient, theoretical combustion temperature, heat transfer, exhaust gas temperature