1990 Volume 76 Issue 11 Pages 2025-2032
Effects of flux and slag volume on the characteristics of post-combustion were studied by using a 10 t ladle type test furnace with pre-treated molten pig iron. Three kinds of flux were used : CaO, CaO-MgO and SiO2, and amount of flux addition was varied between 3 to 15 kg/t.
Followings are brief results.
In the case that the cavity depth by O2 jet was lower than 150 mm deep, the post-combustion ratio decreased in every flux addition as compared with no flux addition. Especially, SiO2 flux addition caused the lowest post-combustion ratio.
From the results of heat balance, it was made clear that the heat efficiency for heating the bath decresed sharply in SiO2 flux adding heat.
The reason is considered to be that, in SiO2 flux adding heat, slag foaming was very high.
Some mechanisms are proposed to explain the decrease of the post-combustion ratio by the addition of SiO2 flux.