Exploring a bioproduct mill

The Äänekoski bioproduct mill was inaugurated in October 2017, replacing an old pulp mill that had been running at the site since 1985. It's the biggest wood processing plant in the Northern Hemisphere and the largest investment in the history of the Finnish forest industry. It can produce up to 1.3 million tons of pulp per year as well as bioproducts like tall oil, bioelectricity and wood fuel.

The mill produces more than double the amount of energy it needs to run. So once it reaches full capacity at the end of 2018, it's expected to generate 1.8 terawatts of power each year — or about 2.5 percent of Finland's electricity production. And all of this without using fossil fuels.

Ninety percent of the wood used at the mill is certified and most of it is grown in sustainably managed Finnish forests. The mill's operator, Metsä Group, says 100 percent of the raw materials and side streams that reach the plant are also used in a resource-efficient way for products and bioenergy.

Processes such as pulp bleaching have damaging consequences for the environment, but the mill operator says it has taken steps to reduce these impacts and limit the amount of landfill waste. Nevertheless, local traffic and noise pollution near the site are set to rise significantly: A total of 240 raw wood lorries and 70 flat wagons will soon be arriving at the mill each day.

Pulp production requires huge amounts of water, but the mill's goal is to implement closed water cycles and an effective wastewater treatment process. Some environmental concerns have been raised, however, including questions about how the mill's thermal load could impact temperatures at nearby Lake Kuhnamo. In terms of air quality, the company says emissions will meet limit values set by the EU.