Vaskiluodon Voima Oy has placed an order with Fortum for nitrogen oxide (NOx) reduction equipment for its Vaasa power plant. Fortum’s solution uses combustion technology to reduce nitrogen oxides generated in the power plant boiler’s combustion process. The rest of the emissions are reduced by injecting urea into the boiler. The equipment will be delivered during 2019 and commissioned in early 2020.
Vaskiluodon Voima generates electricity and district heating at the power plant located in Vaskiluoto, Vaasa. The district heating produced covers more than 60% of the demand in the City of Vaasa. The modification will enable the power plant to comply with the tightening restrictions on emissions.
“The solution is very cost-efficient and the use of additional chemicals is minimal, compared to traditional reduction equipment. For our customer, it was important that the operating expenses remain reasonable; we will achieve that by reducing the nitrogen oxides already during the combustion phase,” says Kristian Rehnström, General Manager, Finnish and Baltic Markets, Fortum eNext.
The EU has repeatedly tightened the emissions limits of various flue gases through the Industrial Emissions Directive (IED). Taking effect in 2010, the IED lowered the nitrogen oxide emissions limit to 200 mg per cubic meter. The emissions limits affect combustion plants with a thermal input of over 50 MW, and compliance with the new limits must be met during 2020−2023. The modification work at the Vaasa power plant will achieve compliance with the new limits.
Reducing nitrogen oxides is part of curbing climate change
NOx emissions are generated in transportation, as well as in energy production during the combustion process of coal-, peat- and multifuel-fired power plants. Nitrogen oxides acidify nature and weaken air quality in cities.
“Reducing nitrogen oxide emissions plays an important role also in the mitigation of climate change. Nitrogen oxides acidify water systems and soil and have an impact on forest growth, which in turn prevents the formation of carbon sinks,” notes Rehnström.
Decades of experience in reducing power plant nitrogen oxides
The key aspect of the NOx technology developed by Fortum in the early 1990s involves impacting the combustion process by modifying the over firing of the combustion air. The solution is an efficient and in terms of operating expenses economical way to reduce emissions because significantly less nitrogen oxides it generated.
The approximately 50 coal-fired boiler modification projects Fortum eNext has performed in the EU area since 1994 have reduced the boilers’ emissions into the air. These modifications have reduced NOx emissions cumulatively by more than 700,000 tonnes, of which more than 100,000 tonnes in Finland. By comparison, Finland’s total NOx emissions were 130,000 tonnes in 2017.