Working Group on LBE Technology

Background

Lead-bismuth eutectic (LBE) is a very effective nuclear coolant because of its low melting temperature, high boiling temperature and neutronic transparency. In addition, LBE itself is a very efficient spallation target for neutron generation via a high-energy proton accelerator. On the other hand, liquid metal corrosion and embrittlement are major issues that must be dealt with in using LBE as a nuclear coolant and spallation target. Thus, LBE continues to be the subject of considerable research in the U.S, Europe and Asia, specifically within the framework of the Accelerator Driven Transmutation Systems and fast-spectrum reactors. A joint working group that addresses the major issues associated with the use of LBE as a nuclear coolant in a unified framework would be of benefit to all the interested parties.

Initially, the working group will function under the Accelerator Reliability and Utilization subgroup of the Working Party on Partitioning and Transmutation (WPPT). After the WPPT mandate expires, the working group will function as a working group under OECD/NEA until the outlined objectives are met.

Working group objective

The objectives of the working group are

• to coordinate and guide the LBE research in participating organizations, while enhancing closer and broader-based collaboration,
  
  
• develop a set of requirements and standards and a consistent methodology for experimentation, data collection and data analyses,
  
  
• to publish the results in a consistent format within a single document in the form of a handbook to provide designers with a single source of qualified properties and data, and to guide the subsequent development efforts.

Working group scope and deliverables

Consistent with the above objective, the scope of the working group includes:

• Development of oxygen control strategies and evaluation of their effectiveness as a function of operational strategies, thermal-hydraulic parameters and different alloys for structural materials;
  
  
• Development of a unified calibration standard for the oxygen sensors;
  
  
• Oxygen sensor development, calibration and evaluation of their effectiveness as a function of thermal-hydraulic parameters;
  
  
• Instrumentation development and testing for reliable operations of LBE coolant loops;
  
  
• Development and evaluation of corrosion- and embrittlement-resistant alloys or surface coating techniques;
  
  
• Corrosion and liquid metal embrittlement experiments and data analyses;
  
  
• Effect of irradiation on the corrosion control strategy (e.g. effect hydrogen generation in the LBE and structures on oxide layer) and corrosion;
  
  
• Effect of spallation and activation products on corrosion control strategy and liquid metal corrosion;
  
  
• Effect of irradiation on the liquid metal embrittlement; and
  
  
• Establishment of the limitations on instrumentation caused by radiation field.

Within the scope of the working group irradiation tests include high-energy proton irradiation, mixed proton and neutron irradiation typical of spallation targets and surrounding areas, and fast-spectrum neutron irradiation typical of fast reactors.

The main deliverable of the working group will be an LBE handbook. The handbook schedule is provided in the table below.

In addition, the working group will publish a joint 5-year test plan in January 2004. After 5 years, continuation of the working group and further updates to the handbook will be re-evaluated based on the needs of the national programs. If the effort is terminated at the time, all participating organizations will have equal copyrights on the previously published data and the versions of the handbook.

Working group membership

The membership for the working group requires:

• A strong R&D program and supporting resources (hardware, test facilities and intellectual resources) within the participating organizations with respect to LBE corrosion and liquid metal embrittlement.
  
  
• Adequate independent source of funding for contributing the technical tasks leading up to the long-term objectives cited above.

Initially, eight organizations/countries will form the working group

CEA/CNRS (France)
DOE (LANL/UNLV) (USA)
ENEA-Brasimone (Italy)
FZK (Germany)
JAERI (Japan)
KAERI (S. Korea)
PSI (Switzerland)
SCK-CEN (Belgium)

The working group will be formed by one member from each participation state/organization. Additional member organizations/countries, that meet the above requirements, may be added to the working group in the future by consensus of the group.

Initially, the group will be chaired by the chairman of the Accelerator Utilization and Reliability subgroup under WPPT, who is currently Dr. Kemal O. Pasamehmetoglu from U.S.A. The secretarial duties will be assumed by Dr. Byung-Chan Na from OECD/NEA.

After completion of the WPPT charter, the working group will transition into a new structure independent of the WPPT. At that time, depending upon the status of the workload, a new chairman will be appointed by the OECD.

Working group meetings

A minimum of one working group meeting per year will be held. Depending upon the needs, a second meeting in a year also may be necessary, especially when there is sufficient volume of work to be incorporated into the handbook. In between meetings, the work will be coordinated by remote communications (e.g. e-mail, tele- or video-conference, etc…).

The meeting location will rotate among the participating organizations/countries. The meetings are expected to last at least two days and the actual duration will be determined by the chairman for each meeting depending upon the amount of new information to be reviewed.

It is the chairman's responsibility to organize and conduct the meeting. Outside the working group members listed above, the attendance to the meetings is limited to people approved by the working group chairman. The chairman may invite subject matter experts to participate in certain meetings to assist the group members or to make specific technical presentations.

Working group documentation

Meeting minutes will be published within one month of each meeting. The meeting minutes will summarize the technical progress up to date and the specific discussions, conclusions and action items. A copy of the presentations made during the meeting will be attached to the minutes.

Meeting minutes are primarily used to track progress, share the preliminary data and to guide the work. The meeting minutes will contain preliminary data and will not be distributed outside the participating organization.

The main deliverable of the working group are the Handbook revisions. The working group will publish the revisions after review and approval. Each contributing organization/country maintain full copyrights to the handbook revisions.

Working group budget and funding

The work performed under this working group will be funded by the participating organizations/countries out of their independent research funds. The working group does not have a dedicated funding source.

In general no fund transfer is anticipated between the participating organizations/countries. Occasionally, small amounts of fund transfer may occur for items like sample shipment, sharing test facilities, etc…It is also expected that the working group will provide short term opportunities for visiting scientists in the form of resident researchers in various organizations. The funding for those kinds of activities will be negotiated on a case-by-case basis among the organizations involved.

For more Information on this Subgroup, please contact Claes Nordborg (Claes.Nordborg@oecd.org

For more information on activities managed/supported by the NSC, please contact Claes Nordborg (Claes.Nordborg@oecd.org) Return to the NSC Home Page