Method for sampling and analyzing gamma spectrum of primary loop coolant of nuclear power plant

The invention relates to the technical field of nuclear power plant nuclear chemistry sampling analysis, in particular to a nuclear power plant primary loop coolant sampling analysis gamma spectrum method. The method comprises the following steps: 1, acquiring a loop coolant sample; calculating the time interval t of the sample from leaving the ideal water body of the primary loop coolant system to entering the sample bottle; 2, decay treatment is conducted on a primary loop coolant sample, setting is conducted on a high-purity germanium gamma spectrometer analysis input system, and the nuclide specific activity of the sample is measured. And step 3, calculating an FRI value according to the obtained specific activity data of the nuclide I-134 and the nuclide I-131. According to the method, the technical effect of reducing the storage time of the RCP high-radioactivity sample in a nuclear island laboratory is achieved through the technical means that the sampling time of the input high-purity germanium gamma