The Baltic Sea is connected to the world’s oceans only through narrow straits. Water renewal in the sea through this channel has diminished in intensity over the last decades. With its closed character, its ecosystem is far more fragile than those found in many other seas. The most serious environmental challenge of the Baltic Sea is increasing pollution and eutrophication caused by excessive amounts of nitrogen, phosphorus and other harmful substances entering the sea. The Baltic is the world’s most polluted sea.
Outokumpu shoulders its responsibility for the Baltic Sea through an action plan for its major production facility, Tornio Works, which is located on the Baltic shore in Northern Finland. The Tornio Works includes ferrochrome and steel mills, and a mine in Kemi that produces chromite ore concentrate. The mills have an annual production capacity of about 500,000 tonnes of ferrochrome and 1.7 million tonnes of stainless steel.
The Tornio mills and mine have an impact on the Baltic Sea both by creating effluents and by using water in their operations. The making of stainless steel requires processes in high temperatures, in which Outokumpu Tornio uses about 15 million m3 of cooling water annually. Outokumpu seeks to progressively reduce its water usage. In terms of effluents, the Works is making a concerted effort to further reduce its watercourse loading. Cooling water is not an effluent per se, but exceptionally it is factored into the environmental loading of the Tornio Works. For this reason, the reported loading of the Works is higher than that of equivalent industrial facilities in the EU.
Since 2000, the environmental performance of Tornio Works has been improved in several respects. Levels of zinc and solid discharges and the volume of cooling water used have been reduced. Developments in the steel making process have halved nitrogen oxide discharges to the sea, and oil discharges to water have been reduced to such low levels that they cannot be measured under normal conditions.
In 2010, the project to utilize a suction-dredging basin located by the Works, through which all effluents will be discharged into the sea, has moved on as planned. At Tornio Works the extra sedimentation pool was taken in use in June 2011. After this, effluents from the Works will stay in the basin for several months. This will give solids in the water time to settle to the bottom of the basin, which means that they will not be discharged with the effluent into the sea. Nitrogen amounts will also be reduced significantly. The lowering of discharges is also investigated at the cold rolling mill of the Works, which is the main unit causing water discharges (metals and nitrogen). During 2012, also the sanitary treatment facility of the Works was renewed as part of continuous efforts to minimize its impact on the environment. It has been decided that from 2013 on all sanitary waters at Tornio will be conducted to the local municipal water-cleaning unit, further reducing emissions to the sea.
"The new use of the suction-dredging basin by the Works will mark a significant improvement in the way that we manage effluents from Tornio Works," says Juha Kekäläinen, manager of environmental affairs. "It is important to constantly investigate new ways for reducing our environmental loading, even if the environmental effects from effluents, according to yearly follow-up studies, are already almost minimal."