Primary Simulation: The Yield of 14C Produced in PWR During Normal Operation

Abstract

The mechanisms of the radionuclide 14C production and releasing from pressurized water reactor (PWR) nuclear power plant (NPP) are simply described in the paper. The yield calculation model for 14C produced in PWR is offered in this work. The averaged neutron flux in reactor core under normal operation condition is simulated with MCNP5 according to the simplified Daya Bay NPP reactor core structure and other parameters, the yields and activities of 14C in different parts of the reactor core including fuel, fuel cladding, nitrogen impurities in fuel and coolant are calculated and compared with Origen2. The simulation results showed that the yields of 14C produced in different parts change linearly with operation time. The rations of 14C introduced by nuclear reactions in coolant, fuel cladding, nitrogen impurities in fuel and fuel element core are 64%, 16%, 12%and 8%, respectively. The dominant part of 14C is induced by neutron reactions with coolant. The primary study results may offer some reference values for 14C releasing in environment control from NPP.