Detection of Gaseous Heavy Water Leakage Points in CANDU-6 Pressurised Heavy Water Reactors

Abstract

During reactor operation, the heavy water filled primary coolant system in a CANDU 6 Pressurized Heavy Water Reactor (PHWR) may leak through routine operations of the plant via components, mechanical joints, and during inadvertent operations etc. Early detection of leak points Is therefore important to maintain plant safety and economy. There are many independent systems to monitor and recover heavy water leakage in a CANDU 6 PHWR. Methodology for early detection based on operating experience from these systems, is investigated in this paper. In addition, the four symptoms of D2O leakage, the associated process for clarifying and verifying the leakage. and the probable points of leakage are discussed.