CN116195006A

CN116195006A - Underground nuclear reactor with explosion relief chamber

Info

Publication number: CN116195006A
Application number: CN202180006185.5A
Authority: CN
Inventors: 帕尔文纳纳桑·加内森
Original assignee: Pa ErwennanasangJianeisen
Current assignee: Pa ErwennanasangJianeisen
Priority date: 2021-09-08
Filing date: 2021-12-13
Publication date: 2023-05-30
Also published as: WO2023038656A1

Abstract

An underground nuclear reactor having a hollow explosion tunnel extending from one end of a containment member and housing a nuclear reactor, a heat exchanger, a generator, etc. A nuclear reactor or the like is located on the movable support member. The detonation tunnel defines a detonation chamber having a plurality of spaced apart fragment deflectors therein. The explosion chamber has an upper wall with a top opening formed therein, the top opening being selectively closed by a top portion. If maintenance or replacement of the reactor is required, the top section is opened to allow the reactor to pass therethrough into the explosion chamber and outwardly through the top opening. If the reactor explodes, the explosion drives fragments to pass through the explosion vent and enter the explosion chamber, and the deflector reduces the explosion force when the fragments pass through the explosion chamber. A simplified cooling system is provided.

Description

Underground nuclear reactor with explosion relief chamber

Cross Reference to Related Applications

The present application is a continuation-in-part application Ser. No. 17/183,923, filed on 24, 2, 2021, entitled "underground Nuclear energy reactor with explosion relief Chamber (UNDERGROUND NUCLEAR POWER REACTOR WITH A BLAST MITIGATION CHAMBER)".

Technical Field

The present invention relates to nuclear reactors, and more particularly, to underground nuclear reactors. Even more particularly, the present invention relates to underground nuclear reactors having an explosion-mitigation chamber associated therewith. Even more particularly, the present invention relates to an underground nuclear reactor having a simplified emergency cooling system.

Background

Nuclear reactor systems have been arranged to protect the reactor in the event of a destructive event. The applicant has previously obtained several patents which represent a significant advance in nuclear reactor technology. See, for example, U.S. patent nos. 9,378,855B2, 9,396,823B2, 9,502,143B2, 10,170,209, 10,685,751B2, and 10,714,221. In pending application No. 17/183,923, entitled "underground nuclear reactor with explosion relief chamber (UNDERGROUND NUCLEAR POWER REACTOR WITH A BLAST MITIGATION CHAMBER)", filed by applicant at 24, 2, 2021, the applicant provides a convenient means for removing a nuclear reactor from its containment structure for repair or replacement. In the same application, the applicant provides a unique emergency cooling system. The present application represents an improvement over the inventions of this co-pending application.

Disclosure of Invention

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key aspects or essential aspects of the claimed subject matter. Furthermore, this summary is not intended to be used as an aid in determining the scope of the claimed subject matter.

A nuclear reactor in accordance with the present invention includes a containment member comprising:

(a) A bottom wall having a first end, a second end, a first side, a second side, an upper side, and a lower side;

(b) An upstanding first end wall having a lower end, an upper end, an inner side, an outer side, a first end and a second end;

(c) A first end wall extends upwardly from the first end of the bottom wall;

(d) An upstanding second end wall having a lower end, an upper end, an inner side, an outer side, a first end, and a second end;

(e) A second end wall extends upwardly from the second end of the bottom wall;

(f) The second end wall of the receiving member has a channel formed therein;

(g) An upstanding first sidewall having a lower end, an upper end, an inner side, an outer side, a first end and a second end;

(h) A first side wall extending upwardly from a first side of the bottom wall;

(i) An upstanding second sidewall having a lower end, an upper end, an inner side, an outer side, a first end, and a second end;

(j) A second sidewall extending upwardly from a second side of the bottom wall;

(k) An upper wall having a first end, a second end, a first side, a second side, a lower side, and an upper side;

(l) The upper wall extending between the upper ends of the first end wall, the second end wall, the first side wall and the second side wall such that the containment member defines an interior compartment therebetween; and

(m) the upper wall of the containment member is located below ground level so that the containment member is fully buried under the ground.

The invention comprises an elongate, horizontally disposed hollow detonation tunnel including a detonation chamber extending from a second end wall of a containment member, the detonation chamber comprising:

(b) An upstanding first sidewall having a lower end, an upper end, an inner side, an outer side, a first end and a second end;

(c) A first side wall extending upwardly from a first side of the bottom wall;

(d) An upstanding second sidewall having a lower end, an upper end, an inner side, an outer side, a first end, and a second end;

(e) A second sidewall extending upwardly from a second side of the bottom wall;

(f) An upstanding first end wall having a lower end and an upper end;

(g) The first end wall extends between the first end of the first side wall and the first end of the second side wall;

(h) An upstanding second end wall having a lower end and an upper end;

(i) The second end wall extends between the first side wall and the second end of the second side wall;

(j) The upper wall extends at the upper ends of the first end wall, the second end wall, the first side wall and the second side wall;

(k) The upper wall has a top opening formed therein, the top opening being selectively closed by a top portion;

(l) The first end wall of the explosion tunnel having a passageway formed therein in communication with the passageway of the second end wall of the containment member;

(m) an optional vent is movably positioned in the passageway of the second end wall of the containment member and the passageway of the first end wall of the explosion tunnel, the vent being movable from a normally closed position to an explosion-opened position; and

(n) the vent may also be selectively opened to allow removal of the nuclear reactor from the containment member for replacement and/or repair.

In a preferred embodiment, the detonation tunnel is constructed of concrete. In a preferred embodiment, the deflector is selectively removably secured to the side wall of the detonation tunnel.

In a preferred embodiment, a simplified cooling system is provided for cooling the reactor vessel in case of emergency.

In a preferred embodiment, the nuclear reactor vessel, heat exchanger, turbine and generator are mounted on a movable support member in a containment member, which enables the nuclear reactor to be more easily removed from the containment member and explosion relief chamber for repair or replacement.

The main object of the present invention is to provide a nuclear reactor containment with both passive cooling and explosion relief.

It is a further object of the present invention to provide a nuclear reactor containment wherein some or all of the power generating groups may be moved into and out of the containment system for repair or refueling.

It is another object of the present invention to provide an explosion relief system that functions to divert the force of an explosion to a lateral direction and to control the force of the explosion in an explosion relief chamber when a nuclear reactor is exploded.

It is another object of the present invention to provide a nuclear reactor that is protected from missile attack or aircraft crashes.

It is a further object of the present invention to provide a simplified passive cooling system that is not affected by earthquakes and is used in combination with an explosion-mitigating section and a protective section that protects against missile attack or aircraft crashes.

It is another object of the present invention to provide a nuclear reactor in which the components of the nuclear reactor and the power generating set are mounted on a movable platform.

It is a primary object of the present invention to provide an explosion suppression chamber for an underground nuclear reactor.

It is a further object of the present invention to provide an explosion suppression assembly that includes an explosion chamber that not only can suppress the explosion of an underground nuclear reactor in an explosion, but also can be used to enable the reactor to be removed from its underground containment structure for repair or replacement.

These and other objects will be apparent to those skilled in the art.

Drawings

Non-limiting and non-exhaustive embodiments of the present invention are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified.

FIG. 1 is a partial side cross-sectional view of the present invention showing a top section of an explosion chamber elevated from the explosion chamber in phantom;

FIG. 1A is an enlarged portion of FIG. 1 showing components of a nuclear reactor and power generation assembly mounted on a movable wheeled platform;

FIG. 2 is a partial cross-sectional view of a nuclear reactor vessel;

FIG. 3 is a partial upper cross-sectional view of the present invention;

FIG. 4 is a view similar to FIG. 3 except that the nuclear reactor has undergone an explosion or blast;

FIG. 5 is a partial top cross-sectional view that more fully illustrates the invention;

FIG. 6 is a partial side cross-sectional view showing the nuclear reactor vessel fluidly connected to a conduit through cooling water; and

fig. 7 is a view similar to fig. 1, except that the power generation pack is located at the ground surface.

Detailed Description

Embodiments are described more fully hereinafter with reference to the accompanying drawings, which form a part hereof, and which show, by way of illustration, specific exemplary embodiments. These embodiments are disclosed in sufficient detail to enable those skilled in the art to practice the invention. Embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. The following detailed description is, therefore, not to be taken in a limiting sense, since the scope of the present invention is defined only by the appended claims.

The applicant has previously obtained U.S. patent nos. 9,378,855B2, 9,396,823B2, 9,502,143B2, 10,170,209, 10,685,751B2 and 10,714,221, which relate to nuclear reactors. While applicant's earlier patent relates to a floating nuclear reactor, the present invention relates to an underground nuclear reactor and an explosion-mitigation chamber. The disclosures of the above patents are incorporated herein by reference in their entirety, if necessary, to complete the present invention. Furthermore, as used herein, the term "fluid" may include "steam".

The underground nuclear power reactor of the present invention is designated by reference numeral 10 (fig. 1). The ground surface of the buried nuclear reactor 10 is indicated by reference numeral 12 and the ground surface or upper surface thereof is indicated by reference numeral 14.

The underground nuclear reactor 10 includes containment members 16. The receiving member 16 includes a bottom wall 18 having a first end 20, a second end 22, a first side 24, a second side 26, an upper side 28, and a lower side 30. The receiving member 16 includes an upstanding first end wall 32, the first end wall 32 having a lower end 34, an upper end 36, a first end 38, and a second end 40. The receiving member 16 further includes an upstanding second end wall 42, the second end wall 42 having a lower end 44, an upper end 46, a first end 48 and a second end 50 extending upwardly from the end 22 of the bottom wall 18. The second end wall 42 has a passageway 51 formed therein as will be described hereinafter.

The receiving member 16 includes an upstanding first side wall 52 having a first end 54 and a second end 56 extending upwardly from the first side 24 of the bottom wall 18. End 54 of side wall 52 is joined to end 38 of end wall 32. End 56 of side wall 52 is joined to end 48 of end wall 42.

The receiving member 16 also includes an upstanding second side wall 58 having a first end 60 and a second end 62 extending upwardly from the second side 26 of the bottom wall 18. End 60 of side wall 58 is joined to end 40 of end wall 32. End 62 of side wall 58 is joined to end 50 of end wall 42.

The components of the nuclear reactor 10 are mounted on the movable support member 66 and have an upper side 68, a lower side 70, a first end 72, a second end 74, a first side 76, and a second side 78. A plurality of casters 80 are secured to the underside 70 of the support member 66, the support member 66 engaging the upper side 28 of the bottom wall 18 such that the support member 66 is positioned above the bottom wall 18.

The nuclear reactor 10 includes a vertically disposed reactor vessel 82, the reactor vessel 82 having an upper end 84, a lower end 86, and an interior compartment 88. As shown in fig. 2, the inner end 92 of the conduit 90 is in fluid communication with the upper end of the interior compartment 88. A conduit 94 extends outwardly from the conduit 90 outside the container 82 and a valve 96 is provided therein. A valve 98 is provided in the conduit 90 outside the conduit 94.

As shown in fig. 2, the inner end 102 of the conduit 100 is in fluid communication with the lower end of the interior compartment 88. As shown in fig. 2, a conduit 104 extends from the conduit 100 and a valve 106 is provided therein. As shown in fig. 2, the conduit 100 has a valve 108, which valve 108 is provided in the conduit 100 outside the conduit 104. The pump 100 is disposed in the conduit 100 outside of the conduit 108. As shown in fig. 1A, the conduit 90 and the conduit 100 extend into the heat exchanger 112 and are connected together by a conduit 116 as shown in fig. 1A, the heat exchanger 112 having an interior compartment 114.

A steam line or conduit 118 extends from the interior compartment 114 of the heat exchanger 112 to a turbine 120 that drives an electrical generator 122. A return line 124 extends from turbine 120 to condenser 126, and a leg 128 extending upwardly from support 66 raises condenser 126 above support member 66. A line 130 extends from an underside 132 of the condenser 126 to a lower end of the interior compartment 114 of the heat exchanger 112. While the turbine 120, generator 122, and condenser 126 are preferably located in the receiving member 16, they may also be located at the ground 14 as shown in FIG. 7. If so positioned, these components are typically enclosed in a building or shed.

As shown in fig. 6, the

pipes

94 and 104 extend outwardly through the receiving member 16 to a buried water tank 134 having cooling water 136 contained therein. As shown, the tank 134 has a vent tube 138 extending upwardly therefrom to a position above the ground 14. As also shown in fig. 6, the

pipes

94 and 104 are connected together by a cooling pipe 139 extending therebetween, surrounded by cold water in the tank. Preferably, the conduit 94 has a flexible slack formed in the conduit 94 inside the receiving member 16 and outside the receiving member 16. Preferably, the tube 104 has slack formed in the tube 104 inside the receiving member 16 and outside the receiving member 16.

Reference numeral 190 designates an explosion relief assembly of the present invention. The explosion mitigation assembly 190 includes an elongated hollow tunnel member 193, the elongated hollow tunnel member 193 having an inner end 194 and an outer end 196. The tunnel member 193 includes a horizontally disposed bottom wall 198, an upstanding outer end wall 200, an upper wall 202, a first side wall 204, and a second side wall 206.

Walls

198, 200, 202, 204, and 206 of tunnel member 193 define an interior explosion relief chamber 208. The inner end of explosion relief chamber 208 has a channel 210 formed therein, with channel 210 aligned with channel 51 in receiving member 16. An optional explosion vent 212 is hingedly mounted in channel 51 and channel 210, preferably made of steel. The vent 212 is normally closed but is movable to an open position, as will be described in more detail below. The

channels

51 and 210 are large enough to allow the nuclear reactor 80, heat exchanger 116, and associated equipment to be moved therein for repair or replacement.

As shown, a plurality of elongate and vertically disposed deflectors 214 are secured to the inner surface of the wall 204 in a horizontally spaced apart manner. As shown, a plurality of elongate and vertically disposed deflectors 214 are also secured to the inner surface of the wall 206 in a horizontally spaced apart manner. As shown, the deflector 214 extending inwardly from the wall 204 is horizontally offset relative to the deflector 214 extending inwardly from the wall 206. Preferably, the deflector 214 is composed of concrete, but may be composed of steel or the like, if desired.

Preferably, each deflector 214 has a triangular or trapezoidal cross-section defining angled front and rear faces 214A, 214B. Preferably, the lower end of the deflector 214 is located on the upper side of the bottom wall 198. Preferably, the deflector 214 is selectively secured to its respective side wall by a flange 216 and bolts 218. The inner ends of the flanges 216 are embedded in the respective deflector 214 and the outer ends are bolted to the respective side walls. The deflector 214 is attached to the corresponding sidewall to enable removal of the deflector from the chamber 208 to enable cleaning of the interior of the chamber 208 and movement of the nuclear reactor through the chamber 208 for repair or replacement. Numeral 220 designates a top portion that can selectively close a top opening 222 formed in the upper wall 202.

It is sometimes necessary to repair or replace the reactor 80 and the heat exchanger 116. In this case, the top portion 220 is raised to open the top opening 222. Subsequently, the vent 212 will move to its open position. Typically, deflectors 214 on

walls

204 and 206 will remove explosion chamber 198 to remove reactor 80 and the like from containment member 16. Subsequently, reactor 80 or the like is moved through passageway 51, passageway 192 and passageway 210, through explosion chamber 208, and outwardly through top opening 222 for repair or replacement.

The optional vent 212 includes a closure mechanism designed to allow the vent 212 to open when the reactor is broken by overpressure and the vent 212 is subjected to a predetermined explosion pressure. The breakage of the reactor can also result in breakage and damage to other components in the containment member 16, such as the steam generator, turbine, generator, condenser, and support structure. The broken reactor and its associated components strike the vent 212, and the vent 212 is opened by the force of the explosion, thereby allowing the broken reactor components and other component fragments to pass through the passage 51 and passage 210 and into the explosion relief chamber 208.

The pressure wave and reactor fragments strike the innermost deflector 214 on the wall 206, resulting in a reduction in explosive force. Fragments of the reactor and components are redirected to the next deflector 214 on the wall 204 and then travel to and from the deflector 214 until the end of the chamber 208, such that the explosive force is reduced each time a fragment strikes the front face of the deflector 214. Eventually, the explosive force is reduced to a safe level, so that the top portion 220 can be opened, thereby cleaning the explosion relief chamber 208 and cleaning the receiving member 16. If the reactor vessel 82 were to overheat, the normally closed valve 96 would open allowing hot fluid from the interior compartment 88 of the reactor vessel 82 to pass through the conduit 94, cooling tube 139 and conduit 104. The water surrounding the tubing 139 cools the tubing and the fluid within the tubing. Valve 106 will open allowing cooling fluid from the interior of conduit 139 to return to the bottom of interior compartment 88 through conduit 104 and conduit 100.

It can thus be seen that the invention achieves at least all of its ends.

Although the invention has been described in language specific to certain structures and method steps, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific structures and/or steps described. Rather, the specific aspects and steps are described as forms of implementing the claimed invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.

Claims

1. A nuclear reactor underground, comprising:

a female member comprising:

(b) An upstanding first end wall having a lower end, an upper end, an inner side, an outer side, a first end, and a second end;

(c) The first end wall extends upwardly from the first end of the bottom wall;

(e) The second end wall extending upwardly from the second end of the bottom wall;

(f) The second end wall of the female member having a channel formed therein;

(g) An upstanding first sidewall having a lower end, an upper end, an inner side, an outer side, a first end, and a second end;

(h) The first side wall extends upwardly from the first side of the bottom wall;

(j) The second side wall extends upwardly from the second side of the bottom wall;

(l) The upper wall extends between the upper ends of the first end wall, the second end wall, the first side wall and the second side wall such that the female member defines an interior compartment therebetween; and

(m) said upper wall of said containing member being located below ground level whereby said containing member is fully buried under the ground;

a nuclear reactor vessel located within the interior compartment of the containment member;

the nuclear reactor vessel having an upper end, a lower end, and an interior compartment;

the lower end of the reactor vessel being located at the upper side of the bottom wall of the containing member;

a vertically disposed heat exchanger having an upper end, a lower end, and an interior compartment located in the interior compartment of the female member;

the lower end of the heat exchanger being located on the bottom wall of the containing member adjacent the reactor vessel;

a power generation system located in the interior compartment of the containing member adjacent to the heat exchanger and driven by the heat exchanger;

the power generation system includes a condenser located on the bottom wall of the containing member;

an elongated hollow detonation tunnel, the elongated hollow detonation tunnel comprising:

(b) An upstanding first side wall extending upwardly from the first side of the bottom wall, the first side wall having an upper end, a lower end, a first end, a second end, an inner side and an outer side;

(c) An upstanding second side wall extending upwardly from the second side of the bottom wall, the second side wall having an upper end, a lower end, a first end, a second end, an inner side and an outer side;

(d) A first end wall having an upper end and a lower end, being located at the first end of the bottom wall, and having a passage formed therein, the passage communicating with the passage in the second end wall of the female member;

(e) A second end wall having an upper end and a lower end, said second end wall extending between said second ends of said first and second side walls at said second end of said bottom wall;

(f) An upper wall located at the upper end of the first end wall of the detonation tunnel, the second end wall of the detonation tunnel, the first side wall of the detonation tunnel, and the second side wall of the detonation tunnel; and

(g) The wall of the explosion tunnel defines an explosion chamber configured to receive fragments from the nuclear reactor in the event of an explosion of the nuclear reactor thereby generating an explosive force extending from the nuclear reactor;

(h) A cooling water tank located in the ground adjacent the nuclear reactor vessel; and

(i) A conduit in fluid communication with the interior compartment of the reactor vessel and passing through water in the cooling water tank.

2. A subterranean nuclear reactor according to claim 1, wherein the conduit in fluid communication with the interior compartment of the reactor vessel and through the water in the coolant tank has one or more flexible slack portions formed therein.

3. The underground nuclear reactor of claim 1, wherein the upper wall of the detonation tunnel has a top opening formed therein, wherein a top portion is located on the detonation tunnel, the top portion being located in the top opening to normally close the top opening, but the top portion is selectively movable to an open position.

4. The underground nuclear reactor of claim 1, wherein a plurality of spaced apart first deflectors are secured to the inside of the first sidewall of the detonation tunnel to partially reside in a path of fragments passing through the detonation tunnel from the first end of the detonation tunnel toward the second end of the detonation tunnel, and wherein a plurality of spaced apart second deflectors are secured to the inside of the second sidewall of the detonation tunnel to partially reside in a path of fragments passing through the detonation tunnel from the first end of the detonation tunnel toward the second end of the detonation tunnel.

5. The underground nuclear reactor of claim 4, wherein the first deflector is vertically disposed and horizontally spaced, and wherein the second deflector is vertically disposed and horizontally spaced.

6. The underground nuclear reactor of claim 5, wherein each of the first and second deflectors has an angular shape.

7. The underground nuclear reactor of claim 1, wherein the passage is sufficiently large to allow the nuclear reactor to pass through the passage for repair or replacement.

8. A subterranean nuclear reactor according to claim 3, wherein the top opening is sufficiently large to allow the nuclear reactor to pass through the top opening for repair or replacement.

9. The underground nuclear reactor of claim 1, having an explosion vent movable between open and closed positions and positioned in the passageway to close the passageway when the vent is closed.

10. A nuclear reactor underground, comprising:

a female member comprising:

(c) The first end wall extends upwardly from the first end of the bottom wall;

(f) The second end wall of the female member having a channel formed therein;

(m) said upper wall of said containing member is located below ground level, whereby said containing member is fully buried under the ground;

a movable supporting member located in the interior compartment of the containing member on the upper side of the bottom wall of the containing member;

the movable support member having an upper side and a lower side;

a nuclear reactor vessel located on the upper side of the movable support member;

the lower end of the heat exchanger being located on the upper side of the movable support member adjacent the reactor vessel;

a power generation system positioned on the upper side of the movable support member adjacent to the heat exchanger and driven by the heat exchanger;

the power generation system includes a condenser positioned on the upper side of the movable support member;

(e) A second end wall having an upper end and a lower end, said second end wall being located at said second end of said bottom wall, said second end wall extending between said second ends of said first and second side walls;

(g) The wall of the explosion tunnel defines an explosion chamber configured to receive fragments from the nuclear reactor upon explosion of the nuclear reactor, thereby generating an explosive force extending from the nuclear reactor.

11. A nuclear reactor as claimed in claim 10, wherein a plurality of wheels are located on the underside of the movable support member.

12. The underground nuclear reactor of claim 10, wherein the upper wall of the detonation tunnel has a top opening formed therein, wherein a top portion is located on the detonation tunnel, the top portion being located in the top opening to normally close the top opening, but the top portion is selectively movable to an open position.

13. The underground nuclear reactor of claim 10, wherein there is a cooling water tank located in the ground adjacent the nuclear reactor vessel, wherein a conduit is in fluid communication with the interior compartment of the nuclear reactor and passes through water in the cooling water tank.

14. The underground nuclear reactor of claim 13, wherein a portion of the conduit in fluid communication with the interior compartment of the nuclear reactor and passing through the water in the cooling water tank is flexible and slack.

15. The underground nuclear reactor of claim 10, wherein a plurality of spaced apart first deflectors are secured to the inside of the first sidewall of the detonation tunnel to partially reside in a path of fragments passing through the detonation tunnel from the first end of the detonation tunnel toward the second end of the detonation tunnel, and wherein a plurality of spaced apart second deflectors are secured to the inside of the second sidewall of the detonation tunnel to partially reside in a path of fragments passing through the detonation tunnel from the first end of the detonation tunnel toward the second end of the detonation tunnel.

16. The underground nuclear reactor of claim 15, wherein the first deflector is vertically disposed and horizontally spaced, and wherein the second deflector is vertically disposed and horizontally spaced.

17. The underground nuclear reactor of claim 16, wherein each of the first and second deflectors has an angular shape.

18. The underground nuclear reactor of claim 10, wherein the passage is sufficiently large to allow the nuclear reactor to pass through the passage for repair or replacement.

19. A nuclear reactor underground, comprising:

a female member comprising:

(c) The first end wall extends upwardly from the first end of the bottom wall;

(f) The second end wall of the female member has a passage opening formed therein;

a nuclear reactor vessel located in the interior compartment of the containment member;

a power generation system located above the ground level of the containing member, driven by the heat exchanger;

(g) The wall of the explosion tunnel defines an explosion chamber configured to receive fragments from the nuclear reactor upon explosion of the nuclear reactor, thereby generating an explosive force extending from the nuclear reactor;

a water tank having cooling water therein located in the ground adjacent the reactor vessel; and

a conduit in fluid communication with the interior compartment of the reactor vessel and passing through water in the cooling water tank.

20. The underground nuclear reactor of claim 19, wherein a portion of the piping in fluid communication with the interior compartment of the nuclear reactor vessel and passing through the water in the cooling water tank is flexible and slack.

21. A nuclear reactor as claimed in claim 19, wherein the lower ends of the reactor vessel and the heat exchanger are located on a movable support member.