CN117976259A - Small-sized nuclear power module - Google Patents

Abstract

The present invention provides a small-scale nuclear power module, which comprises: a water pool; and a containment shell placed in the water pool, a small-scale reactor is arranged in the containment shell, wherein the containment shell is filled with an inert gas. Compared with the prior art, the small-scale nuclear power module of the present invention comprises a water pool and a containment shell placed in the water pool, a small-scale reactor is arranged in the containment shell, and the containment shell is filled with an inert gas. During normal operation, the containment shell is filled with an inert gas, and the inert gas maintains the pressure in the containment shell at atmospheric pressure or slightly higher than atmospheric pressure, thereby preventing air from leaking into the containment shell and causing a safety accident.

Description

Small Reactor Nuclear Power Module

Technical Field

The present invention relates to the field of nuclear engineering technology, and more specifically, to a small reactor nuclear power module.

Background technique

The containment is the third safety barrier of a nuclear power plant. Its main function is to contain radioactive materials released from the core under normal operating conditions and accident conditions.

At present, large commercial pressurized water reactor nuclear power plants use a large containment due to the large size of the primary loop system. The entire primary loop system, part of the safety system, auxiliary systems, etc. are contained in the containment. The containment forms include concrete containment, concrete containment with steel lining, and steel containment. For small reactors, the primary loop system adopts an integrated design or compact design. The size of the main loop is much smaller than that of large commercial nuclear power plants. The use of relatively compact or compact containment is conducive to modular manufacturing, transportation, installation and operation, and simplifies system configuration.

However, in existing small-scale nuclear power reactors, air is easily leaked into the containment, thereby causing safety accidents. In view of this, it is indeed necessary to provide a small-scale nuclear power module that can prevent air from entering the containment.

Summary of the invention

The purpose of the present invention is to provide a small-scale nuclear power module which can prevent air from entering the containment vessel.

In order to achieve the above-mentioned object of the invention, the present invention provides a small reactor nuclear power module, which comprises:

Pools; and

A containment vessel is placed in the water pool, and a small reactor is arranged in the containment vessel;

Wherein, the containment vessel is filled with inert gas.

According to one embodiment of the small reactor nuclear power module of the present invention, the small reactor is an integrated small reactor, including a pressure vessel and a core, reactor internals, a steam generator and a pressurizer arranged in the pressure vessel.

According to an embodiment of the small reactor nuclear power module of the present invention, the outer side wall of the pressure vessel is adjacent to the inner side wall of the containment vessel.

According to an embodiment of the small reactor nuclear power module of the present invention, the containment vessel is filled with nitrogen.

According to an embodiment of the small reactor nuclear power module of the present invention, water is provided in the water pool, and the containment vessel is immersed in the water.

According to an embodiment of the small reactor nuclear power module of the present invention, the containment vessel is a steel containment vessel.

According to an embodiment of the small reactor nuclear power module of the present invention, an upper isolation valve is provided on the top of the containment vessel, and a lower isolation valve is provided on the bottom of the containment vessel.

According to an embodiment of the small reactor nuclear power module of the present invention, the pressure in the containment vessel is not lower than atmospheric pressure.

Compared with the prior art, the small reactor nuclear power module of the present invention includes a water pool and a containment vessel placed in the water pool, a small reactor is arranged in the containment vessel, and the containment vessel is filled with inert gas. During normal operation, the containment vessel is filled with inert gas, and the inert gas maintains the pressure in the containment vessel at atmospheric pressure or slightly higher than atmospheric pressure, so as to prevent air from leaking into the containment vessel and causing safety accidents.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

FIG1 is a schematic structural diagram of a small reactor nuclear power module according to the present invention;

In the figure: containment--1, pressure vessel--2, interval channel--3, lower isolation valve--4, water pool--5, upper isolation valve--6;

Detailed ways

In order to make the invention purpose, technical solution and technical effect of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described in this specification are only for explaining the present invention, not for limiting the present invention.

It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

It should be further understood that the term "and/or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

Please refer to FIG. 1 , the present invention provides a small-scale nuclear power module, which includes: a water pool 5; and a containment vessel 1 placed in the water pool 5, wherein a small-scale reactor is arranged in the containment vessel 1, wherein the containment vessel 1 is filled with an inert gas.

According to one embodiment of the small reactor nuclear power module of the present invention, the small reactor is an integrated small reactor, including a pressure vessel 2 and a core, internal components, a steam generator and a pressurizer arranged in the pressure vessel 2, wherein the pressure vessel 2 has a radiation shielding effect on the core and has the function of preventing the spillover of post-fission products, and the function of the containment vessel 1 is to contain the radioactive substances released from the core under normal operating conditions and accident conditions. It should be noted that since the integrated small reactor is a prior art, the components installed in the pressure vessel 2 (such as the core, internal components, steam generator, etc.) are not shown in FIG. 1.

It should be noted that the shape of the containment vessel 1 can be set to be the same as that of the pressure vessel 2. The containment vessel 1 is used to completely isolate the pressure vessel 2 from the external environment to achieve the function of a safety protection barrier. The containment vessel 1 is the last barrier to prevent the release of fission products to the surroundings, and is used to control and limit the spread of radioactive substances from the reactor to protect the public from harm by radioactive substances.

Furthermore, the containment shell 1 may be made of steel. The steel containment shell 1 has the characteristics of good sealing and low leakage rate. At the same time, the steel containment shell 1 can be prefabricated and welded on site, which is beneficial to shortening the construction period.

According to one embodiment of the small reactor nuclear power module of the present invention, the outer wall of the pressure vessel 2 is adjacent to the inner wall of the containment vessel 1 (close-fitting). Since the diameter of the pressure vessel 2 of the small reactor is small, the close-fitting containment vessel 1 can still ensure that the outer dimensions of the power module are small, and can be manufactured, assembled and transported in a modular manner by land in the factory. The free space inside the close-fitting steel containment vessel 1 is small, and the wall thickness of the containment vessel 1 is large, which can withstand higher accidental internal pressure and has better sealing. When a loss of coolant accident occurs, the pressure inside the containment vessel 1 will quickly balance with the pressure inside the pressure vessel 2, avoiding excessive loss of coolant and exposure of the core.

A spacing channel 3 is provided between the containment shell 1 and the pressure vessel 2, and the spacing channel 3 surrounds the pressure vessel 2. In the illustrated embodiment, the spacing channel 3 may be filled with an inert gas (such as nitrogen). The containment shell 1 is filled with an inert gas to replace the oxygen in the containment shell 1. Under normal operating conditions of the unit, the containment shell 1 maintains atmospheric pressure or slightly higher than atmospheric pressure, thereby preventing oxygen in the environment from leaking into the containment shell 1. Since there is no oxygen in the containment shell 1, internal disasters such as explosion or deflagration caused by the reaction of hydrogen and oxygen generated under design basis accidents or severe accident conditions are actually eliminated.

It is understandable that when the hydrogen concentration in the spacing channel 3 exceeds the combustible concentration limit, combustion or even explosion may occur, causing overpressure and temperature rise in the containment 1, thereby posing a threat to the integrity of the containment 1, and radioactive fission products may be released into the environment, causing serious consequences. For this reason, in the illustrated embodiment, the pressure in the containment 1 is not lower than atmospheric pressure (maintained at atmospheric pressure or slightly higher than atmospheric pressure) to prevent air from leaking into the containment 1 and causing safety accidents.

Specifically, an upper isolation valve 6 is provided at the top of the containment 1, and a lower isolation valve 4 is provided at the bottom. The upper isolation valve 6 and the lower isolation valve 4 are used for the input and output of the inert gas in the containment 1 (that is, the inert gas in the spacing channel 3), so as to facilitate the input and output of the inert gas in the containment 1. Under normal shutdown and refueling conditions, the upper isolation valve 6 and the lower isolation valve 4 need to be opened to discharge the inert gas in the containment 1, so that the water in the heat sink flows into the containment 1. At this time, the core decay heat will be introduced into the final heat sink through the shell wall of the pressure vessel 2, the water between the pressure vessel 2 and the containment 1, and the shell wall of the containment 1, so as to realize the residual heat discharge function under normal operating conditions.

In the illustrated embodiment, a coolant is provided in the water tank 5, the containment 1 body is placed in the water tank 5, the coolant immerses the containment 1, and the coolant can be water or other cooling liquids. The containment 1 of the small reactor nuclear power module is immersed in a water tank 5, and the water tank 5 serves as the final heat sink. Under accident conditions (such as loss of coolant accident), the core heat is released into the containment 1, and the heat will be conducted to the water pool through convection exchange in the shell, heat conduction of the steel containment shell wall, and convection exchange between the shell wall and water, thereby realizing the long-term cooling function of the core under accident conditions.

Combined with the above detailed description of the embodiment of the present invention, it can be seen that, compared with the prior art, the small-scale nuclear power module of the present invention includes a water pool 5 and a containment shell 1 placed in the water pool 5, a small-scale reactor is arranged in the containment shell 1, and the containment shell 1 is filled with an inert gas. During normal operation, the containment shell 1 is filled with an inert gas, and the inert gas maintains the pressure in the containment shell 1 at atmospheric pressure or slightly higher than atmospheric pressure, which can prevent air from leaking into the containment shell 1 and causing safety accidents. In addition, under accident conditions, the heat released by the core will be introduced into the coolant in the placement groove 5 through the shell wall of the pressure vessel 2, the coolant between the pressure vessel 2 and the containment shell 1, and the shell wall of the containment shell 1, which can improve the heat transfer effect on the pressure vessel 2 and enable the pressure vessel 2 to obtain strong and continuous cooling.

According to the above principles, the present invention can also make appropriate changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the scope of protection of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the present invention.

Claims (8)

1. A small reactor nuclear power module, characterized in that the small reactor nuclear power module comprises: Pools; and A containment vessel is placed in the water pool, and a small reactor is arranged in the containment vessel; Wherein, the containment vessel is filled with inert gas. 2. The small reactor nuclear power module according to claim 1 is characterized in that the small reactor is an integrated small reactor, including a pressure vessel and a core, in-core components, a steam generator and a pressurizer arranged in the pressure vessel. 3. The small reactor nuclear power module according to claim 2 is characterized in that the outer wall of the pressure vessel is adjacent to the inner wall of the containment vessel. 4. The small reactor nuclear power module according to claim 1 is characterized in that the containment vessel is filled with nitrogen. 5. The small reactor nuclear power module according to claim 1 is characterized in that water is provided in the water pool and the containment vessel is immersed in the water. 6. The small reactor nuclear power module according to claim 1 is characterized in that the containment vessel is a steel containment vessel. 7. The small reactor nuclear power module according to claim 1 is characterized in that an upper isolation valve is provided at the top of the containment vessel, and a lower isolation valve is provided at the bottom of the containment vessel. 8. The small reactor nuclear power module according to claim 1 is characterized in that the pressure inside the containment vessel is not lower than atmospheric pressure.