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INVESTORS / SAYANOGORSK AS MODERNISATION
SAYANOGORSK AS MODERNISATION
 The
modernisation of the Sayanogorsk aluminium smelter (SAZ), which was built in 1985,
began in 2004. The USD 62 mln programme included significant modernisation
of the casting equipment, trial sections of new RUSAL Aluminium (RA) smelting technology
cells, compensating busbar, modernisations to the anode length, increasing the anode
stud diameter, control systems and replacing transformer rectifiers, an increase
in operational amperage, an upgrade of the gas scrubbers and improvements in the
carbon area (production of pre-baked anodes).
In February 2004, the Company finished the first stage of the casthouse
reconstruction in Sayanogorsk. The smelter received new casthouse equipment for
billets, which had been purchased from Hydro. In May 2006, SAZ commissioned the
new 192 ktpa casting line which allowed production of high-quality extrusion billets.
The modernisation of the casthouse allowed to produce value added products aligned
to RUSAL's marketing strategy.
In 2005 local staff from SAZ and engineers from RUSAL Engineering
& Technology Centre conducted a comprehensive upgrading of the process equipment
and control systems at each of the smelter’s eight gas scrubbers, installing Control
Logix (advanced control software), which made possible the permanent monitoring
of the efficiency of gas treatment and reduced alumina consumption. Each gas scrubber
was equipped with dust sensors, ultrasonic gas flow meters, gauges for bulk materials
and reflection radars for better control of alumina consumption rates. The key objective
of the project was to minimise harmful emissions into the atmosphere. Today, SAZ
is one of the ‘cleanest’ production sites globally, which is mostly achieved through
the excellent performance of its gas scrubbers.
In 2006 SAZ completed the revamping of process equipment and gas
scrubber control systems, which immediately led to a better handling of noxious
atmospheric emissions and reduced incident response time.
Another important environment-saving activity is the effort to extend the service
life of the smelter’s cells: fewer cell rebuilds means less carbon waste and spent
pot lining, and of course, less harmful emissions generated whilst a cell is pre-heated
prior to its start-up. In 2006 the cell service life was extended to 64.4 months.
The better efficiency of cell hoods helped reduce emissions and improve the environmental
statistics inside potrooms. Apart from that, the smelter cut the consumption of
calcined soda which is used in the production of prebaked anodes, and this resulted
not only in an environmental but also a cost saving effect.
According to the environmental modernisation programme, package condenser units
were fully replaced at Rectifier 5 of the experimental potroom, with over USD 68,000
channelled into this project in 2007. PCB (polychlorbiphenyl) containing condensers
were replaced with environmentally friendly units using dielectric mineral oil.
Point feeders were upgraded on all the cells in Potroom 2. Launched in autumn 2007,
the project included the replacement of dosers and local pneumatic equipment with
more reliable ones produced by Festo. Now, crust breakers are adjusted in a matter
of seconds and with practically no physical effort, but before that this took almost
thirty minutes and was highly labour-intensive. The frequency of equipment failures
has been significantly reduced as well, which minimised anode effects, which are
considered as the major contributor to air pollution because they generate most
of the emissions.
In 2007, in order to increase labour efficiency the electrodes
production shop of SAZ started a project involving production of anode holders with
180 mm diameter stubs, and a line load increase. This project helped produce an
additional 13,248.3 tpa. The process equipment was upgraded in order to improve
the quality of prebaked anodes. It served to improve the qualitative characteristics
of prebaked anodes and decreased anode consumption by over 10 kg per tonne of aluminium
produced, also reducing coal dust output by at least 4 kg per tonne of aluminium.
Processing of coke dust generated in the electrode production shop was organised
with the aim to return carbon materials into production.
The construction of the sanitary buffer zone of SAZ is on-going. In the last two
years over half a million trees and shrubs were planted around the smelter. The
work was being carried out as per the design of the VAMI institute (St. Petersburg).
In the construction of the sanitary buffer zone the principles of efficient landscape
and constructive planting were applied involving the use of a wind barrier and protective
structures, and the main environment protecting sectors were defined. The planting
design and location in the buffer zone enables the contaminated air masses to be
captured and prevents them from penetrating the populated areas. The metal workers
are planning further expansion of the smelter buffer zone in 2009.
In 2008 USD 25 mln was invested in the anode production at the
Sayanogorsk smelter. As a result, it is no longer necessary to purchase additional
anode blocks from China and deliver them to Sayanogorsk. The savings resulting from
anode production expansion amounts to over USD 33 mln anually.
In spring 2008 the comprehensive upgrade of the smelter power shop was completed.
Four Russian manufactured air dryers and two air dryers manufactured in Germany
(Zander) were installed. Three ÒÌ-2250 compressors manufactured by Samsung were
commissioned. The objective is to increase compressed air production and improve
its quality in line with the ever-growing aluminium output.
In 2008 the pilot reduction area of SAZ equipped with RA-400 cells was expanded
by adding the RA-400T cells designed for the Taishet aluminium smelter. Approximately
USD 35 mln was spent for designing and introducing the RA-400T cells. The RA-400T
cell is an upgraded version of the base RA-400 model that was started up at SAZ
in 2005 and is intended for industrial use. The capacity of the RA-400T cell is
3 tonnes of aluminium per 24 hours, making it the most powerful cell in the world.
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