Magnox fuel

Stradling GN, Stather JW, Gray SA, et al. 1989. Assessment of intake of an actinide-bearing dust formed from the pond storage of spent magnox fuel. Radiat Prot Dosim 26(l/4) 201-206. 

In addition to indigenous fuel, quantities of SNF have been received at Sellafield from overseas. This includes Magnox fuel from Tokai Mura in Japan and Latina in Italy, and Light Water Reactor (LWR) fuel from Europe and Japan. 

Based on these considerations and the experience from operation of the Windscale Piles, storage in deep water filled pools was adopted for the early Magnox fuel. This storage philosophy was also adopted by the British electricity generating utilities for the majority of their commercial nuclear power stations. 

Magnox fuel was originally stored in open skips in pools with no weather protection. This resulted in chloride contamination of the poolwater by chloride ions entrained in the coastal air. Under these conditions the Magnox cladding materials were susceptible to corrosion but storage was short-term and the fuel was generally reprocessed before penetration of the cladding. 

Sellafield currently accepts fuel from Magnox power stations in the UK and elsewhere, and Magnox fuel will continue to arrive at Sellafield at least until the elosure of Wylfa which is expected to be no later than 2012. Temporary dry storage has been successful... 

AGR fuel is transported to Sellafield in skips which are placed inside lidded containers using a dry inlet facility shared with Magnox fuel in the FHP. The container provides criticality control by segregation so boron addition to the water is unnecessary. The design of the lid allows containers to be triple stacked. After a minimum of 180 days cooling the elements are dismantled. 

Magnox Reactor waste streams include a wide range of materials such as ion exchange (IX) resins, sludge, Magnox fuel element debris (FED), reactor graphite and carbon and stainless steels. Some wastes will exhibit heterogeneity and for many construction materials such as steels there will be radionuclides present which are neutron activation products of trace impurities and were un-quantified at the time of manufacture. 

Fully active laboratory scale experiments were started using firstly a Windscale HAW solution (5000 l/t) generated by the reprocessing of Magnox fuel elements with a burn-up value of 3500 MWd/t. The overall decay time was about 10 months and as the composition was not known, only relative activity measurements were performed. Other fully active HAW solutions were subsequently prepared in Ispra hot cells by dissolving U02 samples irradiated at 26 — 36,000 MWd/t and cooled for about 4 years. Successive TBP batch-extraction steps were carried out under the 1st extraction cycle conditions of the Purex process to remove the bulk of U and Pu. 

British Nuclear Fuels pic (BNFL) provide a complete nuclear fuel cycle service with its sites at Springfields (AGR/Magnox Fuel Fabrication) near Preston and Sellafield (MOX Fuel Fabrication and Reprocessing) in Cumbria. BNFL also generates electricity using Magnox Reactors at Sellafield (Calder Hall) and Chaplecross in Scotland. This paper provides an overview of the Windscale Vitrification Plant (WVP) and reviews the major safety issues associated with vitrification operations. The practicalities of vitrification of Pu using the current WVP process are briefly discussed. 

Fuel Preparation. Magnox fuel cladding is removed and the bare uranium bars fed into a magazine this is then transferred to the reprocessing plant by rail. The fuel cladding is transferred to an... 

Both these factors, the (in practice) limited number of fuel fabricators and changing national policies, have led some countries to make national self-sufficiency in fuel supply a high priority, calling for the early establishment of uranium prospecting and mining and fuel fabrication. It can also lead to the choice of a power plant type which can be fuelled with natural uranium (HWR or MAGNOX). Fuel fabrication is a fairly easy technology, but its introduction locally for an SMPR is hardly justifiable from an economic point of view. 

Storage of spent nuclear fuel under dry conditions is not a new idea, but dates back to the end of the fifties. MAGNOX fuel has been stored in diy vaults since 1957. Under dry conditions, there have been no major problems with MAGNOX fuel storage. In-leckage of rain water into the dry vault at Wylfa power station, however, has led to severe corrosion of a few fuel elements. Also spent fuel elements from research reactors and fast reactors have been stored in the U. S., in Jq>an and France for many years without problems. 

The experience with spent fuel stored in dry vaults is also very encouraging. Besides the storage of MAGNOX fuel there is good experience with storage of fuel assemblies from research reactors in the CASCAD facility at Cadarache and from breeder reactors [10]. In the U. S. spent fuel from the Fort St. Vrain HTGR has been stored in a dry vault store for many years. Modular concrete stor e systems have been developed and licoised for LWR fuel assemblies. 

UK vault Storage of MAGNOX fuel AGR fuel storage proposal (Tomess)... 

Fabrication costs are three or four times greater with steel pin bundles than for Magnox fuel. Has the use of extruded Zr finned fuel cans, together with larger diameter pins, been considered ... 

Figure 2 Photograph of an uncontaminated ALSO Magnox Fuel Can manufactured for the...

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