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INVESTORS / KRASNOYARSK
SMELTER MODERNISATION PROGRAMME
KRASNOYARSK SMELTER MODERNISATION PROGRAMME
To expand primary aluminium output and reduce the environmental impact of the
facility, UC RUSAL’s Engineering & Technology Center developed the
Krasnoyarsk smelter modernisation project which was implemented in 2004 - 2009.
It is a programme of unprecedented scale, investment, scope, and impact. The
modernisation of the Krasnoyarsk smelter encompasses the application of the
world's best practices and achievements to upgrade the aluminium smelting
technology and improve the facility's environmental performance.
The programme included the introduction of alumina point feeders into the
reduction potrooms; the installation of new gas scrubbers; the conversion to
the 'dry anode' technology; an increase of the amperage in the existing
reduction area, the modernisation of the cast houses and many other activities.
The total investment by UC RUSAL into the Krasnoyarsk smelter modernisation
project over 4 years exceeded USD 300 mln.
The modernisation of the smelter led to a reduction in specific harmful
emissions per tonne of aluminium produced. Hydrogen fluoride was reduced by 1.5
times; tar substances by 2.7 times, and benzo(a)pyrene by 2.5 times.
Transition to 'dry anode' technology
The highlight of the programme was the full conversion of the Krasnoyarsk
aluminium smelter to a more environmentally friendly 'dry anode' technology. In
2008, all the pots at the smelter (8 reduction lines) were converted to the
'dry anode' technology.
Introduction of the best-practice technology enabled the smelter to reduce tar
and benzo(a)pyrene emissions and improve working conditions in the reduction
area. Significant reduction of use of raw materials and energy will provide for
positive economic effect. The total investment committed to the project
exceeded USD 29 mln.
Implementation of dry gas scrubbing system
Another important strand of the modernisation was the construction of new
gas scrubbers. 23 gas scrubbing stations equipped with an extra dry treatment
stage are currently running at the smelter, which enables the smelter to
maintain the maximum technically achievable fluorides capture level of up to
99%.
Mounting of automated alumina point feeders
In August 2004, the Krasnoyarsk aluminium smelter embarked on the installation
of automated alumina point feeders. In 2008, all the Soederberg pots in Potroom
No. 21 were equipped with point feeders. The new system feeds alumina to the
pot through a small opening using a set programme, drastically improving the
ambient environment in the reduction potrooms and driving down the number of
pot tending vehicles along with reducing the probability of accidents. Today
the most illustrative outcome is the reduction of specific harmful emissions
per tonne of aluminium produced – by 10% for hydrogen fluoride, and by 30% for
tar substances and benzo(a)pyrene. The new feeding system enables the smelter
to reduce the anode effect frequency and, as a result, significantly drive down
PFC emissions. The measurements taken at the smelter in September 2007 by
specialists from the International Aluminium Institute showed an 80% reduction
in specific PFC emissions against the levels recorded in 1990.
The complete conversion of the smelter to point feeders costs USD30 mln.
Introduction of a tertiary effluent treatment plant
In the end of 2008 a special plant was built at KrAZ for tertiary treatment of
wastewaters and effluents. Improvement of the existing water recycling system
and creation of an effluent treatment system was on-going at the smelter since
2004. The construction of the tertiary effluent treatment plant marked the
final achievement of the 5-year modernisation of the smelter's water recycling
system. Waters treated in the new facility will fully comply with all the
sanitary norms set out in the legislation. Apart from that, the share of
recycled water reused in the production process will grow and, therefore, the
amount of fresh water from Yenisei consumed will go down. The expenses on
construction of this system exceeded RUR 102 mln.
The modernisation programme also encompasses further development of the
smelter's buffer zone.
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