Very simplified boiling water reactors for commercial electricity generation

Patent metadata

Field	Value
Publication number	US-11742099-B2
Application number	US-202016888766-A
Country	US
Kind code	B2
Filing date	May 31, 2020
Priority date	May 2, 2017
Publication date	Aug 29, 2023
Grant date	Aug 29, 2023

Abstract

Nuclear reactors have very few systems for significantly reduced failure possibilities. Nuclear reactors may be boiling water reactors with natural circulation-enabling heights and smaller, flexible energy outputs in the 0-350 megawatt-electric range. Reactors are fully surrounded by an impermeable, high-pressure containment. No coolant pools, heat sinks, active pumps, or other emergency fluid sources may be present inside containment; emergency cooling, like isolation condenser systems, are outside containment. Isolation valves integral with the reactor pressure vessel provide working and emergency fluid through containment to the reactor. Isolation valves are one-piece, welded, or otherwise integral with reactors and fluid conduits having ASME-compliance to eliminate risk of shear failure. Containment may be completely underground and seismically insulated to minimize footprint and above-ground target area.

First claim

What is claimed is:

1. A simplified nuclear reactor system for commercially generating electricity, the system comprising:
a nuclear reactor;
at least one primary coolant loop connecting to two of a plurality of isolation valves of the nuclear reactor; and
at least one emergency coolant source connecting to at least one of the plurality of isolation valves of the nuclear reactor, wherein the nuclear reactor is integrally isolatable from the primary coolant loop and the emergency coolant source by the plurality of isolation valves integral with the nuclear reactor, and wherein each of the isolation valves includes a primary and a secondary actuator in a continuous valve body.

2. The system of claim 1 , further comprising:
a containment, wherein the reactor is inside the containment, wherein the emergency coolant source is outside containment, and wherein the containment is entirely underground.

3. The system of claim 2 , wherein the containment has a personnel access point at a top shield accessible from ground.

4. The system of claim 2 , wherein the nuclear reactor is a maximum 1000 megawatt-thermal rated boiling water reactor having a height that exceeds its width by a factor of at least 3.9.

5. The system of claim 2 , wherein the containment does not include any open coolant pool for emergency cooling.

6. The system of claim 1 , further comprising:
a containment surrounding the nuclear reactor, wherein each of the isolation valves is connected to the one of the primary coolant loop and the emergency coolant source outside of the containment; and
a plurality of penetration seals, wherein each one of the penetration seals lines and seals the containment at each one of the isolation valves.

7. The system of claim 6 , wherein all penetrations that move a fluid coolant to or from the reactor include at least one of the isolation valves, and wherein the containment is fluid-tight up to 300 psig.

8. The system of claim 1 , further comprising:
a containment; and
a silo surrounding the containment and the emergency coolant source, wherein the silo is a seismic structure configured to reduce seismic shocks to the containment, the emergency coolant source, and the nuclear reactor.

9. A method of operating a simplified nuclear reactor system, the system including a nuclear reactor, at least one primary coolant loop connecting to two of a plurality of isolation valves of the nuclear reactor, and at least one emergency coolant source connecting to at least one of the plurality of isolation valves of the nuclear reactor, wherein the nuclear reactor is integrally isolatable from the primary coolant loop and the emergency coolant source by the plurality of isolation valves integral with the nuclear reactor, and wherein each of the isolation valves includes a primary and a secondary actuator in a continuous valve body, the method comprising:
flowing a fluid coolant through the nuclear reactor to transfer heat from the nuclear reactor to the fluid coolant.

10. The method of claim 9 , further comprising:
opening the two of the plurality of isolation valves connecting the primary coolant loop and the nuclear reactor to place the nuclear reactor in a normal operating condition for electricity generation.

Assignees

• Ge Hitachi Nuclear Energy Americas Llc

Inventors

• Hunt Brian S
• Dahlgren Christer N
• Marquino Wayne

Classifications

• Y02E30/00

  Energy generation of nuclear origin · CPC title

• G21C9/004 Primary

  Pressure suppression · CPC title

• G21C1/028

  cooled by a pressurised coolant (cooling arrangements G21C15/00) · CPC title

• G21C1/086

  Pressurised water reactors · CPC title

• G21C9/016

  Core catchers · CPC title