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Titanium-bearing iron ores are widely
ed throu
notably in rock form in South Africa, Russia, Norway a
merica,
apan, South America and New Zealand. Many attempts have been ma
t them i
Despite Abel’s advice, John Parry, Edward Smith and D. Atkinson conducted blast furnace smel
s at New Plymouth in 1868, using the Pioneer Steel furnace. Their first proble
ss
nsand, which choked the furnace and prevented the flow of gases. They solved t
he furnace with consolidated balls of iron sand bonde
However, when they attempted to draw off the molten metal, the tap holes becam
with accretions of a viscous pasty material. Similar problems led to the failure of t
Iron and Steel Company in 1878, after which the New Zealand Government received furt
ce reiterating Abel’s opinion that titanium in the sand was causing the
The Chemical Composition of New Zealand Iron sands
Compare
est non-titaniferous ores, ironsands provide a raw material of relatively low grade, co
y 58-60% iron by weight after physical concentration using magnetic and gravity methods
ng mineral is titanomagnetite, a solid solution of titanium, magnesium, manganese and vanadium in m3O4). Other substances, such as silica, phosphorus and lime, are also present as inclusions. A typical analysis of New Zealand concentrated titanomagnetite gives the compos
eight illustrated in the pie
In a blast furnace, hot air is blown through a mixture of iron ore, coke and fluxes such as limestone, creating conditions suitable for the reduction of iron oxide to metallic iron. The pri
ucing agent is carbon monoxide, formed by reaction of carbon in the coke with oxygen in t
For magnetite ore the reduction reactions are:
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FeO CO <span style=’font-size:14.0pt;font-fami
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In a blast-furnace, the titanium (IV) oxide (TiO2) in titanomagnetite ore is reduced to titanium nitride (TiN), titanium carbide (TiC) and the titanium (II) oxide (TiO).* These stable products have very high melting points and, in large amounts, can produce highly viscous slags. As solids wetted by both molten pig iron and slag, they form accretions and pasty masses, which block the tap holes of the furnace when the metal or slag is drawn off.. BEW
* The Roman numerals IV and II denote the oxidation state of the metal, which specifies the number of units of positive charge resulting from loss of electrons.