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Clear water revival for Lake Vänern

​Our Skoghall Mill lies on Sweden’s vast Lake Vänern, the largest lake in the EU, so water protection is naturally a top priority in its environmental work. But the mill also actively addresses other environmental issues from local noise concerns to global climate change.

Published: 2/2/2014 4:00 PM

Photo / Text: Lasse Arvidson / Fran Weaver

​Gulls and ducks are swimming on the clear waters of the lake, which stretches off southwards to a distant misty horizon. To the east and west, Vänern is fringed by dark forests dotted with autumnal golden birches. But behind us is a huge industrial facility that produces one sixth of the world's liquid packaging board, and this scene has not always been so unspoilt.

"Back in the 1970s, these waters were badly contaminated with fibrous wastes and other discharges," remembers Skoghall Mill's environmental manager Margareta Sandström. "But today we can swim here – and the city of Karlstad's drinking water supply comes from the same bay fed by our treated wastewater outlet. In terms of organic substances, water quality in Lake Vänern is now as good as it was 100 years ago, thanks to many local improvements in industrial and municipal wastewater treatment."

Ecological cooperation

Sandström participates on behalf of us in the work of the Lake Vänern Society for Water Conservation. This organisation provides a forum for discussing issues related to the lake's water quality, and identifying the necessary solutions.
"Skoghall Mill is one of the biggest industrial plants on the lake, so it's vital for us to have an open dialogue with them," says Grete Algesten, one of the society's experts on lake ecology, who is also an environmental advisor at the Värmland County Administrative Board.
Algesten is delighted that the lake has regained its natural clarity. "Its main ecological problems today concern mercury concentrations and the presence of dioxins in fatty fishes, caused by old environmental sins. Another problem is the artificial regulation of water levels, but this is not related to Skoghall."
Nutrient concentrations in the open waters of the naturally nutrient-poor lake are also close to natural levels, but Stora Enso still aims to further reduce nitrogen concentrations in effluent. This is because Vänern's water eventually flows into the Kattegat, where nutrient pollution is problematic.
"Overall water quality is much better than 20 years ago, and Skoghall is one of the facilities that have worked hard to cut pollutant loads," explains Algesten. Thanks to one such significant improvement, resinous acids from the mill's debarking plant are now burnt as biofuels. The levels of these naturally occurring chemicals in mill effluent used to be harmful to fish. "We also enjoy close cooperation with Stora Enso today on regular water quality monitoring and studies of toxicity levels in fish," Algesten adds.

Fresh fish

Just along the lakeshore from the mill, local fisherman Göran Fransson steers his boat into Lillängen Harbour, where he runs a fish-smoking business with his brother Christer Fransson.
The Franssons catch fish for our ecological sampling work, but most of their catches end up on local dinner tables. "The most important fish for us are vendace, pike-perch and perch," says Christer, slicing open a small female vendace to extract its orange-coloured roe, a local delicacy.
Göran has fished these waters for 30 years. "The lake water is certainly much clearer today near the mill where it used to be full of pulp fibres," he says. "Vänern's fish stocks seem to fluctuate cyclically for natural reasons. We don't have any problems around Skoghall – in fact the waters around the mill's outlet are a good place to fish, since the slightly warmer moving water attracts small fish and the bigger fish that eat them," adds Göran.

Investments in technology and know-how

Margareta Sandström explains that in improving the mill's wastewater treatment, building up know-how together with the local university and cooperating with the environmental authorities to identify the necessary changes can be just as important as making major investments: "We recently improved the efficiency of biological wastewater treatment in our aerated lagoon, thanks to such collaboration."
Many of the mill's environmental investments produce double benefits: reducing harmful emissions, while also recovering materials that can be used as biofuels or for other purposes. "We're now using biofuel ash together with wastewater treatment sludge to create a waterproof layer to seal an old landfill area," she adds.
Sandström is pleased to report that Skoghall's emissions to air all fall comfortably within the limits set in the mill's environmental permit. But she emphasises that striving to reduce fossil carbon dioxide emissions is a never-ending task, due to the urgency of global climate change.
Mill director Carl-Johan Albinsson explains that since Skoghall's Energy 2005 project was launched seven years ago, the mill's oil consumption has fallen by 65 percent, leading to corresponding reductions in emissions of fossil carbon. This is largely thanks to the installation of a new efficient recovery boiler and the conversion of an oil boiler to take biofuels. "It helps that we've also done a lot to enhance energy efficiency throughout the mill. The next major step should be to refit our limekiln to use biofuel instead of oil," he adds.
Skoghall Mill produces about 39 percent of the electricity it needs, mainly from biofuels including black liquor, bark, sawdust, and logging residues. "By increasing Skoghall's pulp production the mill could meet more of its own electricity needs," reckons Albinsson.
Shifts in transportation from road to rail are another way to curb emissions. A new container crane enables imported pulp and outgoing board to be transported in the same specially designed containers through our logistical network by ship and train.

Keeping the neighbours warm and content

Surplus heat from the mill is also used in a local community district heating scheme to warm about 5 000 local homes.
Addressing local residents’ concerns is another key aspect of the mill’s environmental work. “Our ongoing investments in new woodyard facilities will further reduce noise levels,” explains Albinsson.
Local odour problems have been virtually eliminated, except during unexpected incidents and during maintenance stoppages. The mill’s communications staff have learnt that by warning neighbours in advance of such events complaints can be minimised.
“On top of our own environmental work, it’s important not to forget the environmental friendliness of our fibre-based packages,” adds Albinsson, referring to a carbon footprint study conducted by the German Institute for Energy and Environmental Research. The study showed that beverage packages made of board from Skoghall generate 28 percent less carbon dioxide, use 51 percent less fossil carbon, and consume 24 percent less energy than bottles made of monolayer PET plastic.