Oak Ridge National Laboratory (ORNL)

Oak Ridge National Laboratory (ORNL) and the University of Tennessee are developing and performance testing an innovative prototype pump for a small, modular, advanced molten salt nuclear reactor (MSR). The reliability of fuel salt circulation pumps is important to MSR commercial deployment since these pumps must operate leak-free for years at high temperature and in an extreme radiation environment. Present generation pumps are restricted to long vertical shafts with bearings located above the salt line, decreasing both pump lifetime and efficiency. This project will incorporate two innovations that will dramatically improve the reliability of molten salt pumps—magnetic bearings and canned rotor structure. This design will eliminate the need for shaft seals, a preferred approach identified in the MSR experiment at ORNL in the 1960s. The proposed pump will also employ advanced electromagnetic materials suited to MSR operating temperatures and radiation levels. Lastly, operating this fuel salt pump and monitoring its performance will require innovative sensors to remotely locate the control electronics. The resulting design will improve MSR plant performance and cost metrics.

If successful, developments from MEITNER projects will inform the development of lower cost, safe, and secure advanced nuclear power plants.