The history and development of the pyrometallurgical processes at Evraz Highveld Steel & Vanadium
WS Steinberg, W Geyser, J Nell
In 1963, the full-scale engineering study for the development of an
iron, steel, and vanadium plant was initiated. This was the birth of
Evraz Highveld and its process flow as it is known today. Highveld
started out as a steelworks that produced steel and vanadiumbearing
slag from a titaniferous magnetite iron ore mined from its
own mine site near Steelpoort. The process utilized co-current rotary
kilns for prereduction, and submerged-arc furnaces for the
production of pig iron with approximately 1.15% vanadium.
Because of various technical challenges that the submerged-arc
furnaces experienced over the years, a decision was taken in 2004
to convert the furnaces to open slag bath (OSB) operation, in order
to enable the maximum production of iron and vanadium while
improving the control over operational parameters. The conversion
proved to be highly successful and, since 2005, three furnaces have
been converted to OSB operation. The fourth furnace will be
converted in the first half of 2011.
The conversion to OSB furnaces not only yields higher
vanadium recovery to the metal at the iron plant, but also improves
the overall throughput of the steel plant. This is the result of the
higher carbon content of the liquid iron from the OSB furnaces,
eliminating the need for anthracite addition to the shaking ladle
process. This reduces the blowing time by approximately 60%.
The conversion of the furnaces to OSB configuration is seen as
an enabling technology change and a prerequisite to the implementation
of other plant improvements that are envisaged. The longterm
vision of EHSV is to convert five furnaces to OSB mode, and
permanently decommission the two remaining submerged-arc
furnaces. This will allow EHSV to maintain current steel and
vanadium production but at a significantly improved overall
efficiency.
Keywords: pyrometallurgy, furnace, open slag bath, Evraz, Highveld.