Water is vital for paperboard manufacturing, because water is needed at every stage of production: water keeps logs fresh; it helps to separate wood fibres for the paperboard production process; and it transports the fibres to different stages of the production process. Water is also needed for cleaning, cooling, and in smaller quantities to create steam for thermal energy production.
However, rather than just using the water, it is recycled – the process water flows through the mill’s systems several times. After the use, the process water is cleaned thoroughly before it is returned back into nature. About half of the water is used for cooling machinery. As the cooling water runs in a separate system there's no need to clean it after use.
Given the need for water in manufacturing, all Metsä Board’s mills have been built alongside lakes and rivers. This safeguards a continuous availability of clean water for our processes. Still, our operations do not prevent or weaken any other parties’ access to water, for example agriculture. The whole Finnish forest industry uses only 0.2% of the available water resources in Finland.
Using the rich water resources responsibly
Metsä Board’s mills are located in the Nordic countries which are, according to World Business Council for Sustainable Development (WBCSD), the world's water richest region. As part of our water risk assessment, all our mills have been evaluated using the Pfister method, and also this water stress index demonstrates that our mills are located in highly water abundant regions.
Nevertheless, we still continuously seek new ways to minimise the use of fresh water in our processes, for instance by recycling our process waters effectively. This minimises our wastewater emissions and saves energy, therefore reducing impacts on the climate. The percentages of recycled and reused water vary from mill to mill, mainly depending on product quality requirements and local water conditions. Our mills have each set their own targets and continuous improvement plans for water use as part of their environmental management systems. Metsä Board has additionally launched a project to calculate the water footprint of our products based on a life cycle assessment.
As an example, Metsä Board’s mill at Simpele, was able to decrease its waste water flow by over 10% during 2017. The main reason for the reduction is a new online water monitoring system which enables efficient separation of clean pump sealing waters from waste waters.
Investment in the new disc filter at Husum paperboard mill in late 2018 will save 30–50 litre water every second and reduce fibre raw material losses by 1000 kg per day. At the same time the investment decreases energy consumption and thus lowers carbon dioxide emissions.
Metsä Board’s sustainable water use is recognised by CDP which has placed our company on the Water A list for four years in a row since 2015.
Water taken from surface waters
In 2018 Metsä Board’s fresh water intake totalled 105.9 million cubic metres. All process water was taken from surface waters such as rivers and lakes. Our process water use per product tonne has decreased by 20% since 2010.