Behavior of Heat Transfer to Molten Metal by Burner Combustion with Addition of Raw Material Particles

Abstract

In order to increase the amount of chromium ore in smelting reduction furnace, it is important to increase the heat supply to the furnace. Many techniques have been developed with the aim of increasing post -combustion. However, the heat transfer efficiency of post -combustion to the molten metal is low. This is also a factor in reduced refractory life. In this study, experiments with a 4 ton furnace and a numerical simulation were conducted to consider a method of promoting heat transfer from burner combustion heat to the metal. The behavior of heat transfer from the burner to the metal by feeding heated particles of raw materials through the flame was investigated. It was found that:
1) The temperature increment of the metal is increased by feeding of heated particles of raw materials through the burner flame.
2) The quantity of heat transferred from the flame to the metal increases as the feeding rate of heated particles is increased.
3) From the results of the numerical simulation, both the particles temperature and the flame temperature decrease as the particle feeding rate increases. However, the total sensible heat of all particle raw materials increases.
4) As the feeding rate of heated particles increases, heat transfer from the flame by radiation and convection decreases, and heat transfer by the sensible heat of the heated particles increases.
As a result, the particles heated by the flame function as a medium of heat transfer from the flame to the molten metal.