atw - February 2015

European Decommissioning Academy
NucLab Macoule
Change Management - From Power Generation to Decommissioning
Analysis for High Temperature Gas-cooled Reactors
Japan Steps up Overseas Pace

How Belgium Helped Establish a Surveillance Programme for Argentina’s Atucha-2

NucNet

Collaboration between Belgian experts and Argentina on the commissioning of Argentine reactors helped overcome problems caused by delays with construction. Marc Scibetta, deputy manager for nuclear materials science, from the Belgian Nuclear Research Centre (SCK CEN) gave an interview in which he told some facts to Lubomir Mitev of NucNet.

The cooperation between SCK CEN an Argentina’s Comisión Nacional de Energía Atómica (CNEA) started in 2002. The first project was a support for the safety evaluation of the Atucha-1 reactor pressure vessel.

When Argentina resumed the construction of Atucha-2 in 2006 – originally, construction started in 1981 but was suspended in 1985 due to financial reasons – , SCK CEN was asked to develop and implement a surveillance programme for the unit.

European Decommissioning Academy (EDA): Ready to Start

Vladimir Slugeň

According to analyses presented at EC meeting focused on decommissioning organized at 11 September 2012 in Brussels, it was stated that at least 2,000 new international experts for decommissioning will be needed in Europe up to 2025, which means about 150 each year.

The article describes the European Decommissioning Academy (EDA) which is prepared for the first term in June 2015 in Slovakia. The main goal is a creation of new nuclear experts generation for decommissioning via the Academy, which will include lessons, practical exercises in laboratories as well as 2 days on-site training at NPP V-1 in Jaslovske Bohunice (Slovakia). Four days technical tour via most interesting European decommissioning facilities in Switzerland and Italy are planned as well. After the final exam, there is the option to continue in knowledge collection via participation at the 2nd Eastern and Central European Decommissioning (ECED) conference in Trnava (Slovakia). We would like to focus on VVER decommissioning issues because this reactor type is the most distributed design in the world and many of these units are actually in decommissioning process or will be decommissioned in the near future.

NucLab Marcoule: A Dedicated Waste Management and Dismantling Support Laboratory

Florence Goutelard, Lionel Bec-Espitalier and Olivier Dugne

Formerly dedicated to plutonium production support, NucLab was renovated to perform a wide range of analyses for dismantling, plant operation and process development activities mainly at Marcoule but also for external clients. The laboratory is a CEA entity in the Nuclear Energy Division. It provides services to several industrial operators (nuclear processes and power plants) in the fields of analytical chemistry, radioactivity measu- rements, in situ nuclear measurements, decontamination processes, industrial chemistry processes, and waste treatment. NucLab supports research, production, and dismantling activities in all areas of dismantling operations.

Change-Management: From Commercial Power Operation to Post Power Operation and Decommissioning

Karl Wasinger

Transition from power generation to decommissioning challenges utilities. Power generation is mainly characterized by a stable working environment and constant workload, decommissioning and dismantling, however, by transformation and change. Also, changing requirements for the workforce’s skills challenge the organization and its senior management. Ensuring effective and efficient performance, while maintaining motivation of staff, requires adjustment of management processes as well as of operational organization and human resources management. AREVA has more than 20 years of experience in decommissioning of own nuclear fuel cycle plants in France, as well as of other large plants and power reactors in Germany, the United Kingdom and the US. Therefore, the group has developed and successfully implemented integrated change management processes. The implementation of well-established and proven methods, developed by the productive industry and adjusted to the nuclear regulatory requirements, significantly improves the performance and efficiency of means and methods in use. The AREVA Performance Improvement Process defines concrete approaches to identify and improve potential deficits of productivity in six main areas (decommissioning scenarios and stra-tegies, waste treatment and logistics, operations management, supply chain, regulatory monitoring and controls as well as dismantling operation). Nuclear plant and facility owners around the world benefit from AREVA experts well experienced in execution of large and complex decommissioning projects.

Radio Analytical Non-Destructive Technique in Performance Evaluation of Nuclear Grade Resins Indion ARU 103 and Purolite NRW 5050

Pravin U. Singare

Nondestructive radio analytical technique using 131I and 82Br tracer isotopes was used to assess the performance of two nuclear grade anion exchange resins Indion ARU 103 and Purolite NRW 5050. It was observed that for both the resins under identical experimental conditions, iodide ion- isotopic exchange reaction take place at a faster rate as compared to bromide ion-isotopic exchange reaction. The results of present investigation indicate that during the two ion-isotopic exchange reactions, for both the resins, there exists a strong positive linear correlation between amount of ions exchanged and concentration of ionic solution; and strong negative correlation between amount of ions exchanged and temperature of exchanging medium. Also at a constant temperature of 30.0 0C, as the concentration of labeled iodide ion solution increases from 0.001 mol/L to 0.004 mol/L, the percentage of iodide ions exchanged increases from 77.72 % to 84.60 % for Purolite NRW 5050 resins and from 58.28 % to 65.76 % for Indion ARU 103 resins. Similarly results were observed in case of bromide ion-isotopic exchange reactions for the two resins. The overall results indicate that under identical experimental conditions, Purolite NRW 5050 resins shows superior performance over Indion ARU 103 resins.

Revisited: Euratom`s ownership of special fissile materials

Norbert Pelzer

Among all Treaties on the Foundation of the European Community, seemingly, the Euratom Treaty ist the most unobtrusive one having even nearly been declared dead occasionally. For the opponents of nuclear energy the treaty is a thorn in their side because it aims for the peaceful exploitation of nuclear energy. Actually, the treaty likewise aims for the protection of dangers of nuclear energy and encloses a bundle of collective control instruments. The protective purpose provides the community with a strong position in numerous fields towards nuclear energy users including the right to intervene in the operations of nuclear facilities. The communitie`s position is further strengthened by the communitie`s ownership on special fissile materials.

The EAEC Treaty determines: “Special fissile materials are owned by the community“. The material content of Euratom`s ownership is limited by Article 87 of the EAEC Treaty: Unlimited right of use and consumption is granted to the properly possessors unless obligations of the Euratom Treaty oppose. Inherently, the community does not have these rights.

It was asked what would be left to the owner Euratom if the properly possessor is entitled to unlimited right of use and even right of consumption.

Porous Structure Analysis of Large-Scale Randomly Packed Pebble Bed in High Temperature Gas-Cooled Reactor

Cheng Ren, Congxin Li, Xingtuan Yang, Zhiyong Liu, Yanfei Sun and Shengyao Jiang

A three-dimensional pebble bed corresponding to the randomly packed bed in the heat transfer test facility built for the High Temperature Reactor Pebble bed Modules (HTR-PM) in Shandong Shidaowan is simulated via discrete element method. Based on the simulation, we make a detailed analysis on the packing structure of the pebble bed from several aspects, such as transverse section image, longitudinal section image, radial and axial porosity distributions, two-dimensional porosity distribution and coordination number distribution. The calculation results show that radial distribution of porosity is uniform in the center and oscillates near the wall; axial distribution of porosity oscillates near the bottom and linearly varies along height due to effect of gravity; the average coordination number is about seven and equals to the maximum coordination number frequency. The fully established three-dimensional packing structure analysis of the pebble bed in this work is of fundamental significance to understand the flow and heat transfer characteristics throughout the pebble-bed type structure. Keywords: pebble bed; packing structure; discrete element method.

AMNT 2014: Key Topic | Fuel, Decommissioning & Disposal – Report: Part 1

Redaktion

Summary report on the following Topical Sessions of the Key Topic “Fuel, Decommissioning & Disposal“ of the Annual Conference on Nuclear Technology held in Frankfurt, 6 to 8 May 2014:

  • From Pilot Project to an Industrial Service (Thomas Seipolt)
  • Radioactive Waste Management – Experiences with Interim and Final Storage (Stefan Weber and Ingo Kock)

The other Sessions of the Key Topics “Reactor Operation, Safety”, “Competence, Innovation, Regulation” and “Fuel, Decommissioning & Disposal” have been covered in atw 10 and 12 (2014), 1 (2015) and will be covered in further issues of atw.

Vertiefungskurs 2014: Safety Margins in Nuclear Power Plants: Identify, Quantify and Extend

Matthias Rey

Fifteen speakers dealt with the topic safety margins in nuclear power plants from different points of view at the “Vertiefungskurs 2014“ of the Nuklearforum Schweiz in Olten, 4 and 5 November 2014.

In the context of the “Vertiefungskurs 2014” the safety margins in power plants were considered and quantified and possible extensions have been discussed. The conference started with an in-depth introduction of the basis design of existing nuclear power plants. Thereafter speakers told about the main topics emergency preparedness, knowledge management and safety retrofit of nuclear power plants in operation.

60th year atw: Controlled Energy Generation from Nuclear Fusion

Georg Weiss

Prospects increase, that with a controlled process of nuclear fusion one day an additional nuclear energy source will be commercially exploitable. In what follows, scientific principles according to the most recent research will be presented.

Since approximately 30 years we are aware of the fact, that energy in form of light and heat provided by the sun and other fixed stars since over four billions years resulted from reactions of atomic nuclei. A series of such reactions became known which are considered for „thermonuclear“ processes, for example the carbon cycle by Bethe, where hydrogen is converted into helium.

Most of the reflections and experiments dealt until 1938 with the reaction between nuclei of light elements. The possibility of splitting heavy nuclei was not anticipated .Its discovery by Hahn and Straßmann was a complete surprise – so to speak a rash reaction to release energy at the end of the element row. This “way out” captured the interest of nuclear physicist for more than a decade. Only today, by starting to construct big nuclear power plants – only today, being able to assess the possibilities and limitations of this technology, the idea of energy generation through nuclear fusion steps into the foreground of nuclear research.

Japan Steps up Overseas Pace to Compensate for Nuclear Doldrums at Home

John Shepherd

The recent re-election of Japan’s prime minister Shinzo Abe is seen by many commentators as a largely positive move, in terms of political support for a slow revival of Japan’s commercial nuclear fortunes. But Japan’s nuclear companies cannot expect a return to “business as usual” anytime soon and so have set their sights on overseas markets.

The government has supported Japan’s industrial giants as they renew efforts to enter foreign markets, such as Vietnam and Turkey. It is hardly surprising to note that this move is not popular with some environmentalists and opposition politicians.

Critics argue that Japan is not best-placed to be selling its nuclear know-how and technologies elsewhere in the light of the Fukushima-Daiichi disaster. But those critics fail to acknowledge advances made since plants such as Fukushima-Daiichi were built in the 1960ies.

A report released by Japan’s Institute of Energy Economics (IEE) towards the end of last December showed why nuclear firms desperately need to tap business opportunities overseas.

 

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