Rokkasho reprocessing plant delayed again

08 September 2009

The Rokkasho reprocessing plant, due to be completed last month, will not now be finished until October 2010. The further delay is to allow for cleaning and inspections of the vitrification facility. 


Rokkasho reprocessing plant (JNFL)
The Rokkasho reprocessing plant (Image: JNFL)
Japan Nuclear Fuel Ltd (JNFL) has applied to the Ministry of Economy, Trade and Industry for permission to change the work plan, pushing back the scheduled completion date to next year. The change to the work plan is the 14th made since legislation launching the project was enacted, Atoms in Japan noted, listing some of the work required before commissioning can get back on track.


Most of this seems to concern the vitrification line, where dried out and powdered high-level radioactive waste is mixed with molten glass and poured into flasks for permanent storage.


JNFL will begin cleaning the inside of the vitrification cell in early September. It will then clean the equipment to which liquid waste directly adhered during the earlier testing of the cell. Once cleaning is completed, JNFL will restore insulation resistance and confirm insulating effectiveness by December.


In the meantime, JNFL will also inspect some 220 pieces of equipment that may have been affected by nitric acid contained in the high-level liquid waste used in the vitrification plant's trial run, and repair them if necessary.


The company will subsequently heat the glass-melting furnace and remove the ceiling bricks that had earlier fallen to the bottom of the furnace. It will then remove some glass residue. Once that is completed, JNFL will again inspect the inside of the vitrification cell and prepare to resume the test run of the facility by July 2010. In addition, the company will use a full-scale mock-up to gather and analyze data toward ensuring the resumption of operation of the vitrification facility.


The change in the work plan has also impacted JNFL's schedule for reprocessing used fuel. The Rokkasho facility had been due to reprocess 160 tonnes of fuel during the year ending March 2010, with 320 tonnes scheduled to be reprocessed during the following year. However, with the further delay in the plant's completion, no fuel will be reprocessed by March 2010 and 80 tonnes will be reprocessed in the following year.


Once operational, the maximum reprocessing capacity of the plant is 800 tonnes per year, enough to reprocess the used fuel produced from forty 1000 MWe reactors, according to JNFL. That, the company says, is nearly equal to 80% of annual used fuel generation in Japan.