US 5,130,078 A · Reactivity control system and method

Abstract

A method and system for controlling nuclear reactivity in a nuclear reactor are disclosed. The method includes maintaining a nuclear position solution at an initial poison pressure less than the steam pressure within the reactor vessel. The method further includes channeling a pressurizing fluid into the holding tank for pressurizing the poison solution to a pressure greater than the initial pressure thereof, and draining by gravity the poison solution from the holding tank and into the reactor vessel for mixing with the water to reduce reactivity in the core. The system includes the holding tank, apparatus for channeling the pressurizing fluid from the reactor vessel to the holding tank, apparatus for channeling the poison solution from the holding tank by gravity into the reactor vessel, and a controller for opening a normally closed pressurizing valve and a normally closed drain valve to allow flow of the pressurizing fluid to, and the drained poison solution from, the holding tank through the respective channeling apparatus.

Claims17

Dependent claims

A method of controlling nuclear reactivity in a nuclear reactor vessel having a reactor core for boiling water to produce steam in said vessel at a steam pressure comprising:

maintaining a nuclear poison solution in a holding tank at an initial poison pressure less than said steam pressure during operation of said reactor core;
channeling a pressurizing fluid into said holding tank for pressurizing said poison solution to a second poison pressure greater than said initial poison pressure for allowing gravity to drain said pressurized poison solution;
draining by gravity pressurized said poison solution from said holding tank;
and
channeling said drained poison solution into said reactor vessel for mixing with said water to reduce reactivity in said core.

2 more elements

A system for controlling nuclear reactivity in a nuclear reactor vessel having a reactor core for boiling water to produce steam in said vessel at a steam pressure comprising:

a holding tank containing a nuclear poison solution at an initial poison pressure less than said steam pressure;
means for channeling a pressurizing fluid from said reactor vessel to said holding tank for pressurizing said poison solution to a second poison pressure greater than said initial poison pressure, and including a pressurizing valve being normally closed for preventing flow of said pressurizing fluid to said holding tank;
means for channeling said poison solution from said holding tank by gravity into said reactor vessel for mixing with said water to reduce reactivity in said core, and including a drain valve being normally closed for preventing flow of said poison solution drained by gravity from said holding tank;
and
means for opening said pressurizing valve and said drain valve to allow flow of said pressurizing fluid to, and said drained poison from, said holding tank.

2 more elements

Dependencies are inferred from the claim text.

Reactivity control system and method

Life of this patent

Reactivity control system and method

Life of this patent

Abstract

Claims17