The company, which earmarked US$74 million for the latest environmental retrofitting, modified 1,954 reduction cells for the process at the facility. In all, the producer has invested US$390 million in modernisation projects at KrAZ.

The EcoSoderberg process uses an improved design of the exhaust fume removal system to ensure high levels of hermetic sealing and optimised anode pastе composition. It was developed by RUSAL's  Engineering and Technology Centre.

Its use allows a significant reduction of emissions, particularly for the emissions of tarry materials. RUSAL noted that, during 2011-2020, the second stage of the KrAZ eco-modernisation allowed the smelter to reduce total emissions by 13.7%, while hydrofluoride emissions reduced by 30%.

"The introduction of the EcoSoderberg process is a key part of the company's modernisation program," RUSAL CEO Evgenii Nikitin said.

He also noted that, currently, the process is also being introduced at its other smelters, including BrAZ, IrkAZ, NkAZ and VgAZ. Its total plan includes adding 400 reduction cells across five smelters this year.

"A new system of gas treatment has improved hermetic sealing of the cells, allowing us to effectively catch more than 99% of fluorides, 99.5% of benz (a) pyrene, and at least 96.5% of sulphur oxide. The next stage of our retrofitting efforts will involve deployment of inert anode reduction cells," he added.

KrAZ first began its environmental improvements work in 2004, separating it into two stages. The first involved its smelter building, focusing on commissioning new gas treatment systems, installing an automated production process management system, and introducing the dry anode process.

"As a result of the 16-year environmental program, the smelter's total emissions have been cut by 38%, while fluoride emissions are down by 76%. Today, the smelter's emissions, which end up in the air of the city, are 4.5 times less than they were back in 1980," RUSAL said.