Glazing system
A glazing system is a nuclear system for integrating highly radioactive liquid waste from reprocessing into a leak-resistant glass matrix (see HAW glazing ).
The essential process steps (denitration, drying , calcining and melting ) are carried out in the plant either simultaneously or in successive stages. Ceramic furnaces or metal crucibles, which are heated either directly or inductively, are used for melting. End products are usually borosilicate glass blocks in stainless steel containers. These are also known as glass canisters . At each of the existing or planned reprocessing plants, a glazing system is either already in operation, under construction or planned.
Glazing plants in the individual countries
Germany
In Germany , a vitrification facility , the Karlsruhe Vitrification Facility (VEK), was in operation at the Karlsruhe Institute of Technology (North Campus ) to vitrify the highly radioactive waste (around 60 m³) generated during the operation of the Karlsruhe reprocessing facility (WAK). The hot commissioning took place in 2009 and was completed after 9 months in June 2010.
Belgium
The PAMELA plant was built in Belgium in the 1980s according to the German concept to condition the highly radioactive waste from the operation of the Eurochemic plant. In 1976, Eurochemic and Gelsenberg AG in Essen were granted a patent for the glazing process developed. Between 1985 and 1991, over 900 m³ of liquid waste was put through in 2 ceramic melting furnaces.
China
In Guangyuan in the Chinese province of Sichuan , a vitrification plant will be built in 2014 as part of the German-Chinese project Vitrification Plant China . The aim of the project is the conditioning of highly radioactive liquid waste suitable for disposal by melting it into a so-called borosilicate glass matrix .
France
France was the first country in the world to start large-scale glazing in Marcoule in 1978. With the AVM process (induction furnace with calcine feed) used there, around 1,900 m³ of liquid HAW had been processed into around 2,500 glass blocks by the end of 1999 . The process was further developed for the La Hague reprocessing plant . Two systems (R7, T7) have been in operation since 1989 and 1993, respectively.
Great Britain
In Great Britain , a glazing system ( WVP ) based on the French model was built at the Sellafield site. It started operating in 1990. By 2001, 2,280 containers had been filled with glass. As the plant did not achieve the planned throughput, a third glazing line was built at the urging of the authorities.
India
A vitrification plant ( Tarapur ) has been in operation in India since 1985. Similar plants are under construction in Trombay and Kalpakkam .
Japan
In Japan , a plant based on US technology (ceramic furnace with liquid feed) was built in Tōkai . It started operating in February 1995. The annual production is given as around 420 containers. Another facility using a proprietary process developed by JNC (formerly PNC) is to be built in Rokkasho .
Russia
In 1987 a plant with two ceramic melting furnaces was put into operation in Russia ( Mayak nuclear plant ). One of them has not been available since 1988 due to irreparable damage. The other was then modified and has been back in operation since 1991. A total of 1,300 tons of glass products have been produced so far.
United States
In the USA there are three glazing plants in different project phases. A facility on the Savannah River Site began operations in March 1996. By December 2000, around 3,400 m³ of HAW sludge had been processed and 1,000 stainless steel containers filled with glass. Glazing will take about 20-25 years. In West Valley , the first glass blocks in July 1996 was produced. The existing inventory has now been completely glazed. In Hanford , where the task is the most complex due to the different composition of the waste, construction of the vitrification system for the contents of the 177 underground HAW tanks should begin after the infrastructure has been completed in 2002. The hot commissioning was carried out in 2007.
Web links and sources
- Karlsruhe Research Center via the Karlsruhe Vitrification Facility (VEK)
- KIT supplies technology for glazing plant in China