Caithness Map :: Links to Site Map Paying too much for broadband? Move to PlusNet broadband and save£££s. Free setup now available - terms apply. PlusNet broadband.  

 

Removal of trapped fuel elements from the Dounreay Fast Reactor

30th March 2015

Photograph of Removal of trapped fuel elements from the Dounreay Fast Reactor

The removal of trapped fuel elements from the Dounreay Fast Reactor moved a step closer with the successful trial of bespoke equipment to lift off the top plate.

Decommissioning the 50-year-old experimental reactor is one of the most technically challenging projects in the NDA estate.

In 2012, a camera looked inside the reactor for the first time. Subsequent inspections over a three-month period enabled the Dounreay Fast Reactor (DFR) team to assess the internal conditions in detail, providing an accurate basis for planning future fuel removal.

The reactor top plate, a stainless steel honeycomb structure, has been submerged in hazardous radioactive alkali metal for decades.

Working with Caithness company Enterprise Engineering Services Ltd, the DFR team has now carried out a series of trials, using specialised equipment to demonstrate that sections of the reactor top plate can be removed to release the trapped elements underneath.

The equipment was manufactured and trialled extensively at the company's off-site facility, before installation works on the reactor top were completed successfully and on schedule.

Additional work is planned during the summer to prepare for removal and repackaging of the remaining fuel.

Andy Beckwith, project director for fuels, said:"DFR decommissioning is one of the most technically challenging projects for the NDA estate and the safe removal of the breeder fuel elements is crucial to the site's closure programme.

"This project proves that with a dedicated and committed team of people all working together these challenges can be achieved safely, allowing future DFR decommissioning projects to progress."

Meanwhile, 5 tonnes of cables connected to the hub that once controlled the reactor have been ripped out.

Large quantities of mineral-insulated copper conductors were used because of their resistance to heat and overall strength even when flattened.

The cables fed into equipment used for reactor control, temperature monitoring, trace heating systems and distribution boards. Their removal will allow the DFR decommissioning team to clear old distribution boards and cables from areas next to the reactor floor, in turn making space for the removal of other fixtures and fittings. The work is due to be complete by June.

Project Manager, Suzanne Griffiths, said:"We have now removed approximately five tonnes of cabling and junction boxes from the sphere skirt and underground duct, which has presented many challenges including the safe removal of asbestos."

Fact File
Dounreay's experimental fast breeder reactor, housed inside a steel sphere, led British nuclear R&D during the 1950s and 60s.
Built in the 1950s, the DFR became the world's first fast reactor to provide electricity to a national grid in 1962. Its 14MW output was enough to power a small town like Thurso (population of approx 9,000). It closed in 1977.
The reactor was one of only two ever built in the UK to run on liquid metal - an alloy of sodium and potassium known as NaK.
Following closure, the reactor was defuelled, the liquid metal removed from the secondary circuit and some of the breeder material taken out.
Construction started in 2003 on the plant needed to remove the rest of the breeder material and destruction of the bulk liquid metal in the primary cooling circuit was completed in 2012.
Once the residues of liquid metal have been cleansed from the circuits and all the nuclear material removed, work will begin to dismantle the reactor structure, including the sphere.

 

Related Businesses

 

Related Articles

Graduating Apprentices "the Future Of The Far North"Thumbnail for article : Graduating Apprentices "the Future Of The Far North"
Eleven young people who have completed their Dounreay apprentice training are "very much a part of the future of the far north." Guest speaker Jamie Stone MP told the audience at the apprentice indenture ceremony that took place last Friday that, as Dounreay continues to decommission, the newly indentured apprentices would be an important part of the area's ability to offer a skilled and innovative workforce.   Dounreay Managing Director and former nuclear industry apprentice Phil Craig added: “I am very proud that we are celebrating yet another group of talented apprentices.  
Register For The Nuclear Supply Chain Event
The biggest networking event in Europe for nuclear decommissioning will be held in Manchester.  2 November 2017.  
Doors Open At Unique Nuclear ArchiveThumbnail for article : Doors Open At Unique Nuclear Archive
A unique new archive, funded by the Nuclear Decommissioning Authority, has opened its doors to the public for the first time, bringing together historical nuclear records from all over the UK.   Speaking today at the Nucleus (Nuclear and Caithness Archive) in Wick, NDA chairman Stephen Henwood, said:Today we see a new chapter in the important role Caithness has played in the UK's nuclear history.  
Waste contract signals Dounreay's community commitmentThumbnail for article : Waste contract signals Dounreay's community commitment
Amec Foster Wheeler has been awarded a contract to design and build a new effluent treatment plant at Dounreay.  The agreement signals a landmark move for the Caithness site as the first to incorporate socio-economic commitments following the introduction of a new procurement policy earlier this year.  
New camera provides clear images of bowels of reactorThumbnail for article : New camera provides clear images of bowels of reactor
An off the shelf CCTV camera is providing crystal clear images from the depths of Dounreay's Prototype Fast Reactor (PFR).   Fifty years on from the construction of PFR, the reactor decommissioning team is viewing footage that will enable it to pull apart the innards of the second and last fast reactor to be built in the UK.  
Dounreay meets target for liquid hazard reductionThumbnail for article : Dounreay meets target for liquid hazard reduction
The last of the higher activity liquid waste produced during Dounreay Fast Reactor (DFR) fuel reprocessing has been made safe for future generations.  It is an important milestone in the immobilisation of the historic liquid waste, known as raffinate, created from reprocessing undertaken during the operation of Dounreay's three reactors.  
Highest Hazard Materials Disposed Of At DounreayThumbnail for article : Highest Hazard Materials Disposed Of At Dounreay
The destruction of one of the highest hazards remaining in the Nuclear Decommissioning Authority (NDA) estate has been completed at Dounreay.   Around 68 tonnes of highly radioactive liquid metal coolant was removed from the Dounreay Fast Reactor (DFR) and safely destroyed over a ten year period.  
Connect and innovate at the NDA Estate Supply Chain event
The Nuclear Decommissioning Authority (NDA), in association with the Site Licence Companies (SLCs), invite you to ‘connect and innovate' at their fifth annual event.   Entry is free of charge to delegates and exhibitors.  
Nuclear Archive At WickThumbnail for article : Nuclear Archive At Wick
The PFR stone table with the inscription 'Out of Caithness to the World' will become the centre piece of the NDA Archive when it opens its doors in 2017.   Construction of the new facility has begun at Wick and was officially opened by David Flear, Dounreay Stakeholder Group chairman, when he cut the first turf at an opening ceremony in August.  
From Caithness to the World Thumbnail for article : From Caithness to the World
A ceremonial turf cutting ceremony marked the official start of building work on the new archive that will store nuclear records from across the UK.   David Flear, chairman of the Dounreay Stakeholder Group, dug into the ground at the Wick site where the Nuclear Decommissioning Authority's Nuclear Archive will start to take shape over the next 12 months.  

[Printer Friendly Version]