Separator's Digest - GEA Westfalia Separator Group

30 Process Separator’s Digest 3 | 2008
GEA Westfalia Separator
Crud removal with the new Crudmaster 20
demand for metals
and raw materials
has never Been as strong
in recent years, the world-wide mining industry has been
experiencing an upswing which has been stronger than has been
the case for a long time, mainly due to the much stronger demand
for metal and energy raw materials from the Far east.
in particular, the Chinese economy, with
its above-average growth in demand, is
resulting in a shortage of supply and the
associated effect of rising prices. Because
experts are assuming that this development
will continue, the investment climate in the
mining industry is now better than it has
been for at least 20 years. in Chile, for
instance, where approximately 20 percent
of gross domestic product is generated in
the mining industry, this statement is
particularly applicable. Copper production
is expected to rise to 6 million tonnes in
2009, compared with a probable figure of
5.7 million tonnes in 2008. By the year
2011, investments in the Chilean copper
sector are expected to amount to usd 22
billion.
Liquid extraction for copper,
uranium, cobalt and zinc
the liquid extraction process with acid has
become established for recovering metals
such as copper, uranium, cobalt and zinc.
however, a problem encountered in this
process is the formation of so-called “crud“
in the settling tanks – this is an emulsion
layer consisting of acqueous and organic
components, air and fine solids. Because
this emulsion has a negative impact on the
effectiveness of the extraction process, it
has to be continuously removed from the
recovery process, or its formation has to be
prevented.
3-phase decanter removes the
crud in the extraction stage
one possibility is for the crud to be removed
from the process in the extraction stage. For
GEA Westfalia Separator Process 30
Separator’s Digest 3 | 2008
this purpose, Gea westfalia separator
provides special 3-phase decanters designed
to cope with the extreme requirements of
the product. in the first stage, the decanter
separates the emulsion which has previously
been drawn off from the tank into solids,
aqueous phase and solvent. the water and
solids are removed. the organic phase is
enriched with alumina and is then passed
through a 2-phase decanter. in this way, it
is possible to recover the solvent with such
high quality that it can be recycled back into
the extraction process without having a
negative impact on the effectiveness of the
process.
the “Crudmaster 20“ has been launched
on the market for this purpose. this decanter
is available as a two-phase as well as a
3-phase version; it is also possible to choose