Correction - An earlier version of this article incorrectly stated that Studsvik was to process used steam generators from the Olkiluoto plant. As a few readers have pointed out, Olkiluoto units 1 and 2 are boiling water reactors (BWRs) which, unlike pressurized water reactors (PWRs), do not have steam generators. Apologies for any confusion caused.
Studsvik of Sweden has signed a contract with Finland's Teollisuuden Voima Oyj (TVO) for the dismantling and metal recycling of old heat exchangers from the Olkiluoto nuclear power plant.
Studsvik's facility near Nyköping, Sweden, melts metal scrap, such as stainless steel, carbon steel, copper, aluminium or lead. Melting reduces the volume and weight of the waste, resulting in reduced costs for interim on-site storage and final disposal. The end-product is metal ingots, which can either be immediately free-released as conventional scrap metal or released after a period of decay storage. Residual products (slag, sorted material, cutting and blasting residues and dust from the ventilation filters) and ingots that cannot be free-released are returned to the customer.
Units 1 and 2 at TVO's Olkiluoto plant underwent an extensive modernization programme between 1995 and 1998. In both units, the steam separator, generator and main transformer were replaced; the internal components of the low-pressure turbines and the turbine control and protection system were replaced; and the high-pressure turbine was modified.
Under a SKr 25 million ($3.4 million) contract, the used Olkiluoto heat exchangers will now be transported to Sweden where Studsvik will dismantle them and recycle up to 90% of their metal content. Studsvik will process the steam generators - weighing about 700 tonnes in total - in 2010 and 2011. The remaining non-recyclable material will be returned to Finland for final disposal.
Studsvik has signed several previous contracts for the dismantling and recycling of large components from nuclear power plants. In 2009, Studsvik signed a contract worth some SKr250 million ($34 million) with Canada's Bruce Power for the treatment of 32 used steam generators. The steam generators will be treated at Studsvik's facilities in Sweden between 2010 and 2018. The first 16 generators are scheduled for delivery in the spring of 2010.
The technology which makes it possible to treat the steam generators was developed in a project that Studsvik conducted in cooperation with Ringhals. Studsvik has previously treated steam generators from the Ringhals nuclear power plant in Swedish and the decommissioned Stade plant in Germany.
Nuclear power plants replace steam generators as part of regular maintenance and when they are modernized. According to Studsvik, it is estimated that several hundred steam generators and other large components are stored temporarily at nuclear power plants around the world awaiting efficient treatment methods.
"We see interest from an increasing number of countries in treatment of low- and medium-level metallic material instead of direct disposal," said Leif Andersson, head of Studsvik's Swedish business segment.
Researched and written
by World Nuclear News