15 Oct (NucNet): The Petten high-flux research reactor (HFR) in the Netherlands is scheduled to restart on 16 February 2009, the Nuclear Research & Consultancy Group (NRG) said yesterday.

NRG, which operates the HFR on behalf of the EU�s Joint Research Centre, said that together with Areva NP subsidiary Uddcomb Engineering it has developed a plan to repair the pipe wall of the primary coolant system and return the reactor to service.

�The repair comprises the introduction of a sleeve into a section of pipework of the primary cooling system where corrosion and deformation have taken place,� NRG said. The sleeve will be installed using remote handling equipment and fixed in position by mechanical clamps.

However, NRG said the repair would be �a particularly complex matter� because the pipework section in question is encased in concrete and difficult to access.

�This complicates the repair process and demands rigorous preparation. NRG has, together with Uddcomb and other external consultants, made every effort to develop an appropriate solution for the technical problem? On the basis of knowledge gathered worldwide, the definitive preparations for the repair have now commenced,� the company said.

Shortages of medical isotopes have arisen as a result of HFR�s unplanned outage and those shortages will continue up to mid-February, NRG said. NRG discussed the shortages at a meeting of the Association of Imaging Producers & Equipment Suppliers (AIPES) on 13 October 2008. AIPES represents the pharmaceutical industry and also reactors responsible for isotope production.

NRG said both sides agreed that AIPES should find ways to minimise shortages. Meanwhile, NRG said collaboration between the Netherlands, Belgium and France had led to alternative supplies in the past two weeks which had made a �significant contribution� to easing shortages.

The HFR is a tank-in-pool type, light-water moderated and cooled reactor with forced cooling and 45 megawatt steady thermal power.

NRG said last month that the 2008-09 cycle for the production of isotopes, scheduled for 25 October to 23 November 2008, would be cancelled after it was discovered that a gas bubble stream had been escaping periodically into the reactor�s primary cooling system. The cause of deformations and the gas bubble stream was corrosion on the concrete side of the vessel. This corrosion affected the aluminium material of the vessel.

>>Related reports in the NucNet database (available to subscribers)

Petten Research Reactor Helps Meet Shortage Of Radioisotope (World Nuclear Review No. 49, 7 December 2007)

Ministers Urged To Tackle Shortfall In European Nuclear Medicine Supplies (News No. 72, 9 September 2008)

NRG Considering Repair Options For Petten High-Flux Reactor (News No. 74, 17 September 2008)

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