Clean Soederberg

The majority of aluminium produced in Russia uses Soederberg technology, which was invented in 1920. The development of the aluminium industry, a greater focus on environmental issues and the surge in demand for aluminium has resulted in new discoveries of technology enhancements to reduce the impact on the environment and boost production efficiency.

In 2009, RUSAL’s Engineering and Technology Centre designed a new generation of Soederberg cells, reinvigorating the traditional production technology. The new technology was named “Clean Soederberg” and significantly cut emissions as well as increased production efficiency.

The new technology’s major improvement over its predecessor is the use of colloidal anode instead of traditional anode paste. Colloidal anode contains a much lower amount of pitch, which is the main source of tar substance emissions. A further advantage is the enhanced cells’ structure that also helps to reduce emissions.

The project’s key technical solutions:

• Use of ultradispersed mechanically activated anode paste (colloidal anode)
• Introduction of an efficient gas removal system that ensures a cut in emissions
• Higher impenetrability of reduction cells
• New structure of cathode assembly that prompts a 12 tonnes cut in metal consumption
• Higher level of automation

The technology’s key advantages:

• Reduction of hazardous emissions (the fluoride emissions are cut by 75%)
• 7% cut in anode consumption
• Over a 30% cut in fluoride aluminium consumption

The cells using Clean Soederberg technology were put in operation at Krasnoyarsk smelter in 2009 and showed excellent results. RUSAL plans to gradually transfer all the smelter’s capacities to Clean Soederberg. The company also intends to introduce the technology at Bratsk, Novokuznetsk, Irkutsk and Volgograd smelters.