PPPL-5079

Electrical Detection of Liquid Lithium Leaks from Pipe Joints

Authors: J.A. Schwartz , M.A. Jaworski , J. Mehl , R. Kaita , and R. Mozulay

Abstract:A test stand for flowing liquid lithium is under construction at Princeton Plasma Physics Laboratory. As liquid lithium reacts with atmospheric gases and water, an electrical interlock system for detecting leaks and safely shutting down the apparatus has been constructed. A defense in depth strategy is taken to minimize the risk and impact of potential leaks. Each demountable joint is diagnosed with a cylindrical copper shell electrically isolated from the loop. By monitoring the electrical resistance between the pipe and the copper shell, a leak of (conductive) liquid lithium can be detected. Any resistance of less than 2 k trips a relay, shutting off power to the heaters and pump. The system has been successfully tested with liquid gallium as a surrogate liquid metal. The circuit features an extensible number of channels to allow for future expansion of the loop. To ease diagnosis of faults, the status of each channel is shown with an analog front panel LED, and monitored and logged digitally by LabVIEW.
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Presented at: The 20th Topical Conference on High-Temperature Plasma Diagnostics, Atlanta, Georgia, June, 2014.

Published in: Review of Scientific Instruments 85, 11E824 (2014)

View online: http://dx.doi.org/10.1063/1.4894002

© 2014 AIP Publishing LLC.
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