Determination of the Leakage Area of Radioactive Nitrogen N-16 in Steam Generators in Reactors of KLT-40 Type

摘要

The paper studies a primary-to-secondary leak of nitrogen radionuclide N-16 (T-1/2 = 7.11 s, E-gamma,E- max = 6.134 MeV, v(gamma,max)= 69) through a steam generator in a KLT-40 type reactor (used in ice breakers and floating power units, FPUs) with an ingress of water under pressure P(v)and temperature T(v)heated by a follow-up radioactive steam generation which is released under high pressure P-p through a helical steam duct of the steam generator. The content of the specified radionuclide in steam can be found and estimated by use of methods of gamma spectrometry and measurement of gamma-activity concentration of steam and gamma-radiation dose rate through the use of a simple physical and mathematical model making it possible to specify the reason and to determine the area of a leakage on a helical steam duct. The paper specifies the main areas in the structure of steam generators where radiation characteristics may be measured and their assessment techniques may be applied.