Emergency Cooling System for Improved Reliability for Light Water Reactors

摘要

A passive cooling system using only reactive processes without moving parts to power its startup and operation is designed to maximize the reliability of decay heat removal for the current generation of nuclear power plants and for advanced passive reactors. In order to reduce the number of failure modes processes independent from any external power source—such as the electrical power grid or Diesel generators—are used exclusively for all safety functions.;The system uses the very energy that could cause an accident to circulate cooling water through the steam generator to remove the decay heat, simplifying the design and reducing capital costs significantly. Decay heat generated by the nuclear fuel after reactor shutdown induces coolant circulation from the steam generator to the ultimate heat sink keeping the nuclear fuel at safe temperatures and preventing any release of radioactive fission products to the environment.

主权项

1. A safety system for nuclear reactors to dissipate decay heat after the nuclear reaction is terminated, comprising:
nozzles for circulating a two-phase flow generated by steam produced by the decay heat in a reactor vessel which is injected through a first nozzle configured to create condensation of the steam in the two phase flow by compression shock, the pressure of the fluid in the first nozzle throat being substantially below the pressure of the fluid in the remainder of the system, a cooling loop for directing liquid from the compression shock into a heat exchanger to remove the heat of condensation from the fluid and return the resulting flow to a second nozzle, a startup valve which is operated by releasing stored potential energy to commence flow through the nozzle.