IP Library › Granted Patent US 12,542,220
Granted Patent B2
US 12,542,220 · App. 18/502,577 · Granted Feb 3, 2026

Molten salt reactor containment

Inventor: Derek Haas (Austin, TX)
Assignee: Natura Resources LLC
G21G1/02G21C1/32G21C13/08G21C9/016
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Quick Facts
Patent No.
US 12,542,220
App. No.
18/502,577
Granted
Feb 3, 2026
Kind
B2
Abstract

A containment system for an integral molten salt reactor includes a sealed containment structure defining a containment volume. The containment structure includes a fission product adsorbing/absorbing material. The containment system further includes an integral molten salt reactor housed fully within the containment volume of the sealed containment structure. The integral molten salt reactor may permit circulation of a fuel salt therein being heated by fission reactions, and allow for the export of heat from said fuel salt.

Claims (51)

1 . A method of operating a containment system including an integral molten salt nuclear reactor, the method comprising

operating an integral molten salt reactor that is housed fully within a containment volume of a sealed containment structure, the integral molten salt reactor permitting circulation of a fuel salt therein, and allowing for export of heat from said fuel salt,

retaining fission gases, emitted from a release event, within the containment volume using a fission product adsorbing/absorbing material in cooperation with the sealed containment structure,

supplying inert gas into a drain tank section of the integral molten salt reactor, the drain tank section positioned within the sealed containment structure and elevationally below the fuel salt, wherein the inert gas supplied to the drain tank section generates a pressurized state of the drain tank section sufficient to prevent the fuel salt from gravitationally draining into the drain tank section,

while supplying inert gas into the drain tank section, supplying inert gas into a head space section of an integrally constructed vessel of the integral molten salt reactor, the head space section positioned within the sealed containment structure and elevationally above the fuel salt, wherein the inert gas supplied to the head space section generates a pressurized state of the head space section less than the pressurized state of the drain tank section and defining a pressure differential therebetween,

maintaining the pressure differential by continually supplying inert gas to the drain tank section and to the head space section during operation of the integral molten salt reactor, and subsequent to the operation of the integral molten salt reactor, ceasing the supply of inert gas to the drain tank section thereby gravitationally draining the fuel salt into the drain tank.

2 . The method of claim 1 , further comprising collecting gas emanating from the fuel salt circulated within the integral molten salt reactor in a fission gas void section, the fission gas void section defining the head space of the integrally constructed vessel of the integral molten salt reactor.

3 . The method of claim 1 , further comprising adsorbing and/or absorbing iodine and/or tritium and/or noble gas from the fission gases emitted from the release event.

4 . The method of claim 1 , further comprising

holding the containment volume under negative pressure, and

using the containment volume to provide a thermal barrier between the integral molten salt reactor and an environment exterior to the sealed containment structure.

5 . The method of claim 1 , wherein

the sealed containment structure is configured to enclose a collection of maintainable components associated with the operation of the integral molten salt reactor, and

the method further comprises, prior to the release event, accessing the maintainable components without disturbing the fuel salt of the integral molten salt reactor held within the sealed containment structure.

6 . The method of claim 1 , wherein

the operating of the integral molten salt reactor further comprises introducing a fuel salt into the drain tank section,

the drain tank section is positioned in an integrally constructed vessel of the integral molten salt reactor, and

the drain tank section defines a subcritical region of the integrally constructed vessel.

7 . The method of claim 6 , wherein

the operating of the integral molten salt reactor further comprises transferring the fuel salt from the subcritical region of the integrally constructed vessel to a critical region of the integrally constructed vessel, and

the critical region defines a critical volume for fission reactions and for the circulation of fuel salt therethrough.

8 . The method of claim 7 , wherein

the integrally constructed vessel comprises

a reactor section configured to receive a volume of fuel salt from the drain tank section and heat the fuel salt through fission reactions,

a heat exchange section configured to receive a flow of the heated fuel salt from the reactor section and remove heat therefrom, and

a fission gas void section defining a head space of the integral molten salt nuclear reactor and configured to hold a gas emanating from the fuel salt, and

the transferring of the fuel salt further comprises transferring the fuel salt from the drain tank section to the reactor section by increasing a pressure of the drain tank section to a value greater than a pressure of the reactor section.

9 . The method of claim 8 , wherein the operating of the integral molten salt reactor further comprises maintaining the pressure of the drain tank section at the value greater than the pressure of the reactor section during generation of heat through fission reactions at the reactor section.

10 . The method of claim 9 , wherein the operating of the integral molten salt reactor further comprises, in response to a shutdown event, reducing the pressure of the drain tank section and draining the fuel salt into the drain tank section.

11 . The method of claim 10 , wherein the operating of the integral molten salt reactor further comprises storing the fuel salt, subsequent to the shutdown event, in the drain tank section in a subcritical state.

12 . A method of operating a containment system including an integral molten salt nuclear reactor, the method comprising

operating an integral molten salt reactor that is housed fully within a containment volume of a sealed containment structure, the integral molten salt reactor permitting circulation of a fuel salt therein, and allowing for export of heat from said fuel salt,

accessing a collection of maintainable components associated with the operation of the integral molten salt reactor without disturbing the fuel salt of the integral molten salt reactor held within the sealed containment structure, the collection of maintainable components packed within a fission product adsorbing/absorbing material,

supplying inert gas into a drain tank section of the integral molten salt reactor, the drain tank section positioned within the sealed containment structure and elevationally below the fuel salt, wherein the inert gas supplied to the drain tank section generates a pressurized state of the drain tank section sufficient to prevent the fuel salt from gravitationally draining into the drain tank section,

while supplying inert gas into the drain tank section, supplying inert gas into a head space section of an integrally constructed vessel of the integral molten salt reactor, the head space section positioned within the sealed containment structure and elevationally above the fuel salt, wherein the inert gas supplied to the head space section generates a pressurized state of the head space section less than the pressurized state of the drain tank section and defining a pressure differential therebetween,

maintaining the pressure differential by continually supplying inert gas to the drain tank section and to the head space section during operation of the integral molten salt reactor, and

subsequent to the operation of the integral molten salt reactor, ceasing the supply of inert gas to the drain tank section thereby gravitationally draining the fuel salt into the drain tank.

13 . The method of claim 12 , further comprising collecting gas emanating from the fuel salt circulated within the integral molten salt reactor in a fission gas void section, the fission gas void section defining the head space of the integrally constructed vessel of the integral molten salt reactor.

14 . The method of claim 13 , further comprising retaining fission gases, emitted from a release event from the integral molten salt reactor, within the containment volume using the fission product adsorbing/absorbing material in cooperation with the sealed containment structure.

15 . The method of claim 14 , further comprising adsorbing and/or absorbing iodine and/or tritium and/or noble gas from the fission gases emitted from the release event.

16 . The method of claim 12 , wherein the sealed containment structure is held at a vacuum pressure about the integral molten salt reactor contained therein.

17 . A method of operating a containment system including an integral molten salt nuclear reactor, the method comprising

operating an integral molten salt reactor that is housed fully within a containment volume of a sealed containment structure, the integral molten salt reactor permitting circulation of a fuel salt therein, and allowing for export of heat from said fuel salt,

holding the containment volume under vacuum pressure,

using the containment volume to provide a thermal barrier between the integral molten salt reactor and an environment exterior to the sealed containment structure, and

maintaining a pressure differential between a drain tank section and a reactor section by supplying inert gas from an inert gas supply of an inert gas system, selectively, to the drain tank section via a subcritical gas line extending into the drain tank section and to the reactor section via a critical gas line extending into a critical volume.

18 . The method of claim 17 , further comprising accessing a collection of maintainable components associated with the operation of the integral molten salt reactor without disturbing the fuel salt of the integral molten salt reactor held within the sealed containment structure, the collection of maintainable components packed within a fission product adsorbing/absorbing material.

19 . The method of claim 18 , further comprising retaining fission gases, emitted from a release event from the integral molten salt reactor, within the containment volume using the fission product adsorbing/absorbing material in cooperation with the sealed containment structure.

20 . The method of claim 17 , wherein

the operating of the integral molten salt reactor further comprises circulating the fuel salt within a critical region of an integrally constructed reactor vessel while maintaining a pressure of a subcritical region of the integrally constructed reactor vessel above a pressure of the critical region, and

the subcritical region is fluidly coupled with and elevationally below the critical region.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 5, 2024
From: HAAS, DEREK
To: NATURA RESOURCES LLC
Reel/Frame 067016/0340 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 29, 2023
From: HAAS, DEREK
To: NATURA RESOURCES, LLC
Reel/Frame 065693/0281 →
Continuity (2)
Continuation 18449445 · Aug 14, 2023
Related Publication 20250062047A1 · Feb 20, 2025
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