Behaviour of New Zealand ironsand during iron ore sintering

Titanium-bearing burdens are commonly introduced into blast furnaces to protect the hearlh because the so-called "titanium bear" which is a precipitate of carbide, nitride and carbonitride of titanium may form in the blast furnace hearth if Ti02 is present in the feed [1 , 2J. New Zealand ironsand is a titanomagnetite, containing around 60 wt.% iron, 8 wt.% titanium and other substances such as silica, phosphorus and lime [3, 4]. Since it is competitive in price, introduction of the ironsand into the ferrous feed can reduce the production cost and potentially increase blast furnace campaign life. An appropriate method of inlroduction of ironsand is as a component of the sinter as the small size of ironsand precludes direct charging into the blast furnace. Although the effect of introducing titanomagnetite into iron ore blends has been investigated [1,,2, §],little is known about the detailed sintering mechanism. The present study is aimed at identifying the sintering behaviour of New Zealand ironsand as well as the interaction between New Zealand ironsand and CaO to gain better understanding of sintering mechanism of titanomagnetite.