New commercial opportunities for producers of high purity
alumina (HPA) products are emerging due to the growth of
secondary metallurgy performed in steel ladles, delegates at
the 14th UNITECR in Vienna, were told.
Andreas Buhr, global technical director of refractories at
German speciality alumina supplier Almatis said that the
development of new high purity steel grades over the past few
years is having a positive impact on refractory
Buhr outlined that further opportunities were being created
by an increased appetite for low impurity steel from the
automobile sector and that companies were becoming increasingly
aware of energy losses and the cost savings made possible by
better refractory lining concepts.
Notable examples of progression in steel technology are
basic oxygen furnaces (BOF) replacing open hearth furnaces, the
introduction of continuous casting and the growth of secondary
metallurgy performed in steel ladles, according to Buhr.
Around 60-70% of the world’s refractories are
used in steel making, while the rest are mostly consumed in the
manufacturing of iron, cement, glass and non-ferrous
Extended processing of liquid steel in secondary metallurgy
requires continuous adjustment and improvement of refractory
linings and can be considered among the most important drivers
for refractory innovations, Buhr said.
This type of processing can only be performed with specific
high-performance refractory linings, such as HPA refractories,
which must be thermodynamically stable in contact with steel,
in order to avoid re-oxidising the metal.
Buhr noted that refractories for steel ladle side walls must
also be able to withstand slag attack by aggressive,
metallurgical reactive slag – for example,
calcium-aluminate slag (CaO/Al2O3).
As silica-containing high alumina refractories, such as
andalusite or bauxite, show higher wear rates with aggressive,
low-melting CaO/Al2O3 slag, there has
been a trend towards HPA spinel refractories replacing
andalusite and bauxite in ladle linings, Buhr said.
Despite flat steel industry demand, refractory producers can
still benefit, Alteo’s director of marketing, Mike
Rodgers, told IM on the sidelines of the
conference: "The refractories industry is an old one and it has
its ups and downs."
However, he said that there was still growth in developing
countries such as South America, Vietnam and with the recent
lifting of trade sanctions, Iran.
He added that further opportunities existed in Brazil and
Japan with infrastructure development during the 2016 and 2020