ASSEMBLY AND METHOD FOR INJECTING WATER CONTAINING A NEURTON-ABSORBING ELEMENT TO COOL A NUCLEAR REACTOR CORE IN A CRISIS SITUATION

• US 20130170599A1
• Filed: 11/30/2012
• Published: 07/04/2013
• Est. Priority Date: 11/30/2011
• Status: Active Grant

• Current Assignee: Areva Np (AES Corporation)
• Original Assignee: Areva Np (AES Corporation)
• Inventors: MULLER, Thierry, GUILLAUME, Emilie Maud, BOMBAIL, Jean-Paul, GUILLODO, Michael
• Granted Patent: US 9,240,252 B2
• Time in Patent Office: Days
• US Class Current: 376/282
• CPC Class Codes: G21C 15/182 comprising powered means, e.g. pumps
• CPC Class Codes: G21C 9/033 by an absorbent fluid
• CPC Class Codes: G21D 3/04 Safety arrangements emergency protection of reactor G21C9/00
• CPC Class Codes: Y02E 30/30 Nuclear fission reactors

Abstract

An assembly is provided including a mobile structure including a main pipe equipped with a first end intended to be connected to a water supply and a second end intended to be connected to a circuit connected to the primary circuit of the reactor, and including between these two ends in the direction of circulation of the water, a pump, a water heating device, an injector for continuously injecting the powdered neutron-absorbing element into the water of the main pipe, a first mixer for mixing and dissolving powder with water and a controller driving and controlling the flow rate of the water and the flow rate of the powder injected.

Claims

1. An assembly for injecting water containing a neutron-absorbing element in order to cool a nuclear reactor core of a nuclear reactor in a crisis situation, the assembly comprising:

a mobile structure containing a main pipe, the main pipe including a first end connectable to a water supply, a second end connectable to a circuit connected to a primary circuit of the nuclear reactor and, between the first and second ends, in order to ensure the circulation of water;

a pump;

an injector for continuously injecting the neutron-absorbing element in powder form into the water of the main pipe;

a first mixer for mixing and dissolving the powdered form of the neutron-absorbing element in the water; and

a controller for driving and controlling the flow rate of the water and the powder injected.

2. The assembly as recited in claim 1 wherein the main pipe further includes, between the pump and the injector, a water heater regulated by the controller.

3. The assembly as recited in claim 1 wherein the mobile structure further includes a secondary pipe having a first end connectable to a water supply and a second end connected to the main pipe between the mixer and the second end of the main pipe, the secondary pipe including a pump between the first and second ends thereof.

4. The assembly as recited in claim 3 wherein the main pipe includes, between the second end of the secondary pipe and the second end of the main pipe, a second mixer for mixing the powdered neutron-absorbing element and the water from the secondary pipe.

5. The assembly as recited in claim 4 wherein the second mixer is a mechanical mixer.

6. The assembly as recited in claim 3 wherein a flow rate of the water in the main pipe is lower than a flow rate of the water in the secondary pipe.

7. The assembly as recited in claim 1 wherein the first mixer is a mechanical mixer and ultrasound inducers controlled the by the controller.

8. A method for cooling a nuclear reactor core in a crisis situation using the assembly as recited in claim 1, the method comprising:

transporting the mobile structure to a vicinity of a building housing the nuclear reactor;

connecting the first end of the main pipe to a water supply and the second end of the main pipe to a circuit connected to the primary circuit of the reactor;

controlling the pump of the main pipe, the injector and the first mixer using the controller;

supplying the primary circuit of the nuclear reactor with the water containing the dissolved neutron-absorbing element to progressively cool the nuclear reactor core; and

regulating the flow rates of the water and the powder and the mixer using the controller.

9. The method as recited in claim 8 further comprising heating the water of the main pipe, the water temperature being regulated by the controller.

10. The method as recited in claim 8 wherein the mobile structure further includes a secondary pipe having a first end connectable to a water supply and a second end connected to the main pipe between the mixer and the second end of the main pipe, the secondary pipe including a pump between the first and second ends thereof, the method further comprising:

connecting the first end of the secondary pipe to the water supply;

controlling the pump of the secondary pipe using the controller;

injecting water from the secondary pipe into the main pipe between the first mixer and the second end of the main pipe;

controlling the second mixing system using the controller to provide a secondary mixture of the powder with the water;

supplying the primary circuit of the nuclear reactor with water containing the neutron-absorbing element; and

regulating the flow rates of the water in the main and secondary pipes, the flow rate of the powder, and the first and second mixers using the controller.