Influence of Oxy-Fuel Lance Parameters on the Scrap Pre-Heating Temperature in the Hot Metal Ladle

Abstract

As one of the vital ways to improve the converter heat balance and increase the scrap ratio, scrap pre-heating technology has attracted much attention from researchers. The aim of this paper is to reveal the effect of the oxy-fuel lance parameters on the temperature field, flow field, and scrap pre-heating temperature in the ladle by means of numerical simulations. For this, a three-dimensional mathematical model containing the turbulence model, the porous medium heat balance model, and other models has been developed. The research results show that the rational and correct choice of gas flow rate, lance position, and nozzle angle has an important influence on the temperature field and the average scrap temperature. When the gas flow rate increases, the internal annular combustion zone of the scrap gradually expands, the cold zone at the bottom of the scrap continues to decrease, and the average scrap temperature keeps increasing. When the gas flow rate is 5000 m3/h, and the average scrap temperature reaches 1197 K, the pre-heating time is 9.98 min. Lowering the oxy-fuel lance position helps to reduce the cold zone at the bottom of the scrap and increases the average temperature in the cold zone. Reasonable selection of the nozzle angle is conducive to improving the uniformity of the flow field. When the angle of the nozzle is 15°, the gas circulation zone is the largest, and the time to reach an average scrap temperature of 1197 K is the shortest.

Keywords

• scrap pre-heating
• gas circulation zone
• heating curve
• pre-heating temperature