KR101564553B1 - No-action reactor - Google Patents

Abstract

The present invention relates to a no-action reactor. The purpose of the present invention is to provide a no-action reactor which has a safety system to operate passively without a separate control command at a nuclear reactor accident. The other purpose of the present invention is to provide a no-action reactor which performs a quick and safe cooling process by maximizing the cooling efficiency of the safety system in an integrated nuclear reactor.

Description

No-action reactor

The present invention relates to an unmanned reactor, more particularly, to an unmanned reactor capable of cooling passively generated heat through a simple safety system without operator intervention when a reactor failure occurs.

Nuclear power is generated by rotating the turbine using the energy generated during the fission process to produce electrical energy. Figure 1 briefly illustrates the principle of nuclear power generation in general. The nuclear fission of the fuel in the pressure vessel (or reactor vessel) results in enormous thermal energy that is transferred to the heat exchange medium in the pressure vessel and the heat exchange medium is discharged from the pressure vessel as indicated by the solid arrow in Figure 1 And then circulated in the direction of entering the pressure vessel again through the heat exchanger. The heat energy of the heat exchange medium is transferred to the steam generator while passing through the heat exchanger, and the water in the steam generator causes the phase change by the high temperature and high pressure steam due to heat energy. The generated high-temperature and high-pressure steam is supplied to the turbine as shown by the soft arrow in FIG. 1, and the turbine is rotated by the steam, and the generator connected to the turbine rotates together to generate electricity. The steam, which lost its energy by rotating the turbine, is again caused to undergo phase change to become water, which is again recirculated to the steam generator as indicated by the soft arrow in FIG.

Although FIG. 1 shows only the systems that are the subject of nuclear power generation, in reality, a safety system is necessarily provided in the reactor. As described above, when a reactor is operated, very high heat is generated. Such a high temperature environment is very dangerous and may cause a serious accident when a reactor damage occurs. Therefore, in case of damage to the reactor, a safety system for rapidly cooling the reactor must be provided.

Meanwhile, in the past, large-scale reactors have been constructed to produce as much power as possible, but the need for smaller reactors has recently emerged. For example, it is relatively easy to transfer the electricity generated from the power generation facilities to the required area because of the high population density in Korea. However, in the case where population concentration is low due to the low population density compared with the land area, There are various problems such as excessive power loss during transmission, excessive power transmission equipment cost, and the like. Therefore, it is economically more advantageous to have a small-sized power generation facility in a population-concentrated area, rather than having a very large power generation facility to distribute power in such an environment. In addition, in the case of nuclear reactors that are equipped with large ships or submarines and produce electricity, they must be made even smaller.

Given this trend, a number of safety systems that have been studied and designed to suit large conventional reactors tend to be unsuitable for such small and integrated reactors. More specifically, as a safety system configuration applied to existing nuclear reactors, a configuration in which cooling water accommodated in a reactor vessel is circulated to the outside (eg, a PRHR system) (CMT), a safety injection pump (SI pump), etc.), and an example of which is shown in FIG. 2, which can be seen in FIG. 2 It takes a considerable amount of space due to its own volume or its installation and operation. In some cases, it is difficult to apply to the structure of the integral reactor, and when the volume is reduced, sufficient cooling efficiency can not be obtained as much as desired There was a problem.

On the other hand, if the safety system is configured such that the operation of the safety system must be effected at the moment of an emergency such as the occurrence of a reactor damage, the safety system may not operate properly due to malfunction due to damage to the control system, or There are many risk factors such as failure of the reactor operator to give control orders on time.

Therefore, there is an increasing demand for a safety system applicable to an integrated or small reactor, and a safety system configured to be able to operate passively in the event of an accident without any special control instruction. As a result of this research, European Patent Publication No. 2560172 ("Small light water reactor with passive decay heat removal") and Korean Patent Publication No. 2002-0037105 ("&Quot; Emergency core cooling method and apparatus used ") discloses a small- and integrated-type reactor as described above and a safety system applicable thereto. However, the safety systems disclosed in the prior art also suffer from various problems such as failure to achieve a complete passive operation or insufficient cooling efficiency, which is necessary to be improved.

1. European Patent Publication No. 2560172 ("Small light water reactor with passive decay heat removal & 2. Korean Patent Publication No. 2002-0037105 ("Emergency core cooling method and apparatus using a reactor protection vessel and a compression tank")

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide an unmanned reactor having a safety system that can be actuated passively, . It is another object of the present invention to provide an unmanned nuclear reactor capable of rapidly and safely cooling by maximizing the cooling efficiency of a safety system in an integral nuclear reactor.

According to an aspect of the present invention, there is provided an unmanned reactor comprising: a reactor core; A reactor output control rod 112 into which a lower end portion is vertically movably inserted into the reactor core 111; The reactor core 111 is disposed on the lowermost side and a part of the upper end of the reactor output control rod 112 is exposed to the outside, And a reactor vessel (113) having the reactor output control rod (112) therein; A reactor protection vessel 114 formed inside the reactor vessel 113 so as to be hermetically sealed from the outside and having a vacuum vessel therein; An isolation vessel 115 which is formed in a water tank and accommodates cooling water which is a tertiary coolant C3 and is arranged such that the reactor protection vessel 114 is disposed in the cooling water; The heat exchanger is installed inside the reactor vessel 113 to receive heat from the primary coolant C1 and evaporate the heat exchange medium circulated therein to discharge the heat exchange medium to the steam pipe 116a to operate the turbine, A steam generator 116 for supplying the heat exchange medium to the water supply pipe 116b; The reactor vessel 113 is provided inside the isolation vessel 115 and has one end communicated with the upper end of the reactor protection vessel 114 and the other end communicated with the lower end of the reactor vessel 113, A core cooling heat exchanger (120) for performing heat exchange between the cooling water of the cooling water channel (120); A first check valve 121 provided at an upper portion of the reactor vessel 113 for opening and closing the communication between the inner space of the reactor protection vessel 114 and the inner space of the reactor vessel 113; A second check valve 122 provided at a lower portion of the reactor vessel 113 for opening and closing communication between the other end of the core cooling heat exchanger 120 and the inner space of the reactor vessel 113; . ≪ / RTI >

At this time, the unmanned reactor (100) includes a rupture cooling water tank (140) provided inside the reactor protection vessel (114) and containing cooling water which is a secondary cooling material (C2); A rupture plate 145 provided at a lower end of the rupture cooling water tank 140 and capable of rupture by pressure; As shown in FIG.

The unmanned reactor 100 is provided outside the isolation vessel 115 and has one end communicating with the upper end of the isolation vessel 115 and the other end communicating with the lower end of the isolation vessel 115, A condensing cooler 130 for exchanging heat between the fluid circulating inside and the external environment; As shown in FIG.

The unmanned reactor (100) further includes a coolant drive pump (117) provided on the upper side of the reactor vessel (113) to forcibly circulate the primary coolant (C1); As shown in FIG.

According to the present invention, since the safety system is completely driven, rapid cooling can be performed without any separate control instruction when a reactor damage occurs, thereby minimizing the risk of accidents. In addition, unlike the prior art, the present invention has a compact heat exchanging system including a safety system, which can significantly reduce the volume of the reactor, and is thus very suitable for application to small reactors .

Particularly, the present invention has an advantage that the cooling efficiency is much higher than that of the existing safety system. More specifically, in the reactor of the present invention, a reactor vessel is accommodated in a reactor protection vessel, and the reactor protection vessel is configured to be accommodated in an isolation vessel filled with a coolant. In the present invention, The coolant in the reactor protection vessel is directly subjected to heat exchange with the coolant filled in the quarantined vessel so that the coolant in the reactor vessel is cooled much more than the conventional cooling system in which indirect cooling is performed by indirect heat exchange with a separate heat exchange medium The advantage is high efficiency.

In addition, since the structure of the safety system itself is much simpler than that of the prior art, the volume of the space occupied by the safety system is reduced, so that the size and compactness of the reactor can be further improved.

Fig. 1 shows a general principle of nuclear power generation.
2 shows various examples of conventional safety systems.
Figure 3 shows the construction of the unmanned reactor of the present invention.
FIG. 4 is a diagram illustrating an operation step of an unmanned reactor according to the present invention when an accident occurs.
5 is a time-dependent cooling step of the unattended reactor of the present invention.

Hereinafter, an unmanned reactor according to the present invention having the above-described structure will be described in detail with reference to the accompanying drawings.

FIG. 3 shows an example of the construction of an unmanned reactor of the present invention, and FIG. 4 shows an operation stage of an unmanned reactor according to the present invention in the event of an accident. FIG. 3 shows a small and integrated reactor as a basic structure of the reactor itself. However, the object to which the safety system of the present invention can be applied is not necessarily limited to an integral reactor. Therefore, Fig. 3 should be viewed as a representative example of the unmanned reactor of the present invention, and the configuration of the reactor operation system can be appropriately changed.

Referring to FIG. 3, the reactor operation system in the unmanned reactor according to the present invention will be described first. The operation system of the unmanned reactor 100 of the present invention includes a reactor core 111, a reactor output control rod 112, a reactor vessel 113, a reactor protection vessel 114, an isolation vessel 115, a steam generator 116, .

The reactor core 111 is a central portion of a nuclear reactor, in which a nucleus of a nuclear fuel is combined with a neutron to cause a nuclear fission, which generates heat energy. That is, the reactor core 111 generally refers to a bundle of fuel rods that is a nuclear fuel of the reactor.

The reactor output control rod 112 is inserted into the reactor core 111 so that the lower end thereof can move up and down. The reactor output control rod 112 controls the output of the reactor 100 by adjusting the degree of nuclear fission of the nuclear fuel, ultimately.

The reactor vessel 113 is hermetically sealed to the outside to receive the reactor core 111 and the reactor output control rod 112. The reactor core 111 is disposed at the lowermost side of the reactor vessel 113 and the reactor output control rod 112 is controlled to be movable up and down so that a part of the upper end thereof is exposed to the outside of the reactor vessel 113 Respectively. At this time, cooling water, which is a primary cooling material (C1), is accommodated in the reactor vessel (113), so that heat energy generated from the reactor core (111) is absorbed into cooling water. The cooling water serves not only to cool the reactor core 111 by absorbing the heat energy generated in the reactor core 111 but also to transfer the heat absorbed by the cooling water to the outside to ultimately generate electricity. (This will be described in more detail below in the section of the steam generator 116).

The reactor protection vessel 114 is hermetically sealed to the outside and has the inside of the reactor vessel 113 to protect the outside from high temperature and radiation generated in the reactor vessel 113. The inside of the reactor protection vessel 114, that is, the space between the reactor vessel 113 and the reactor protection vessel 114, is vacuumed so that effective heat insulation can be achieved.

The isolation vessel 115 is formed in the form of a water tank to receive cooling water as a tertiary coolant C3, and the reactor protection vessel 114 is arranged to be disposed in the cooling water. As described above, even if the space between the reactor vessel 113 and the reactor protection vessel 114 is evacuated to a maximum extent, the thermal energy generated in the reactor vessel 113 is very large (convection or conduction) There is a risk that the reactor protection vessel 114 is heated because of the amount of heat transferred to the radiation. Therefore, it is necessary to absorb and absorb this heat energy once more, and the cooling water accommodated in the isolation vessel 115 directly absorbs the thermal energy and serves to cool the reactor protection vessel 114.

The steam generator 116 is installed in the reactor vessel 113 in the form of a heat exchanger. A heat exchange medium is circulated in the steam generator 116 to receive heat from the cooling water in the reactor vessel 113 around the steam generator 116, that is, the primary cooling material C1. Accordingly, the heat exchange medium circulated in the steam generator 116 absorbs heat and evaporates. The heat exchange medium, which has become a gas state at a high temperature and a high pressure, is discharged to the steam pipe 116a to operate the turbine. After the turbine is operated, the condensed heat exchange medium is supplied to the steam generator 116 through the water supply pipe 116b to circulate the steam. The steam pipe 116a and the water pipe 116b are respectively provided with a steam pipe isolation valve 116c and a water pipe isolation valve 116d so as to be disconnected from the outside in an emergency.

When the normal operation is being performed as described above, the cooling water inside the reactor vessel 113 naturally circulates convection. More specifically, it is as follows. When the heat energy generated in the reactor core 111 is absorbed into the cooling water, the cooling water that has become hot rises. When the high-temperature cooling water reaches the steam generator 116 disposed above the reactor core 111, the heat exchange medium in the steam generator 116 and the high-temperature cooling water undergo heat exchange. That is, the heat exchange medium in the steam generator 116 absorbs heat from the high-temperature cooling water. Accordingly, the cooling water of high temperature passes through the steam generator 116, and the temperature of the cooling water is lowered. The cooling water thus lowered absorbs the heat energy generated in the reactor core 111, so that a natural circulation convection as shown in FIG. 3 is achieved.

3, a coolant drive pump 117 is installed in the reactor vessel 113 so that the primary coolant C1 is spontaneously circulated in the reactor vessel 113, . The coolant drive pump 117 is disposed on the upper side of the reactor vessel 113 as shown in the drawing, and is arranged below the water surface of the primary coolant C1 during normal operation (liquid state). As described above, the cooling water that has absorbed heat from the reactor core 111 rises and evaporates near the water surface, discharges the heat, and then descends to reach the steam generator 116. At this time, In the case of the integral type reactor, since the cooling water rising from the reactor core 111 and the cooling water descending to the steam generator 116 are formed close to each other, heat transfer occurs between the cooling water in each path and natural circulation is not smooth You can not. At this time, the coolant drive pump 117 is provided above the steam generator 116 so that the coolant is forced to flow toward the steam generator 116. As a result, heat transfer occurs between the coolant water in each flow path as described above It is possible to carry out smooth circulation as originally designed.

The operating system of the reactor described above is common to existing large or small (integrated) reactors. The operation system configured as described above operates to produce power from the reactor, and during normal operation, this operation system alone does not cause any problem in operation. However, when the reactor vessel 113 is damaged and the cooling water in the reactor vessel 113 leaks, the thermal energy generated in the reactor core 111 can not be absorbed into the cooling water in a sufficient amount, 111) is excessively increased, which may result in more damage such as melting of parts. The safety of the reactor is more important than any other factors such as radiation leakage and so on. Therefore, when the reactor vessel 113 is damaged and leakage of the cooling water occurs, the reactor vessel 113, It is necessary to provide a safety system that quickly cools down.

At this time, as described above, when the safety system is operated only after receiving separate control instructions such as a man's operation, the reactor operator is left out of the room or the person himself or herself is injured. Failure to issue control orders will result in a significant increase in the risk of accidents. Also, in the case of a system in which an automatic control operation such as an electronic control is performed, there is a risk that the system may be damaged due to a high temperature generated due to damage to the reactor, thereby failing to operate correctly. Therefore, it is absolutely necessary to provide a safety system to operate mechanically in response to changes in the physical environment of the reactor damage and cooling water leakage.

In the present invention, the safety system (i.e., the devices for cooling the reactor) is completely driven so that no separate control instructions are required by the operator, thereby allowing quick cooling in the event of damage to the reactor, . In addition, the unmanned reactor of the present invention has a compact construction of the heat exchange system including the safety system, which can greatly reduce the volume of the reactor, and ultimately it can be applied to a small reactor And it is very suitable for use.

The safety system provided in the unmanned reactor (100) of the present invention mainly comprises a core cooling heat exchanger (120). Additionally, a condensation cooler 130 and a rupture cooling water tank 140 may be further included. The configuration and operation of each part will be described in detail below.

The core cooling heat exchanger 120 is provided inside the isolation vessel 115 as shown in the figure so as to be capable of exchanging heat between the fluid circulated in the isolation vessel 115 and the external cooling water. At this time, one end of the core cooling heat exchanger 120 communicates with the upper end of the reactor protection vessel 114, and the other end communicates with the lower end of the reactor vessel 113.

For operation of the core cooling heat exchanger 120, the first reactor check valve 121 and the second check valve 122 are provided in the reactor. The first check valve 121 is provided at an upper portion of the reactor vessel 113 to open and close communication between the inside space of the reactor protection vessel 114 and the inside space of the reactor vessel 113. The second check valve 122 is provided below the reactor vessel 113 to open and close communication between the other end of the core cooling heat exchanger 120 and the inner space of the reactor vessel 113.

When the core cooling heat exchanger 120, the first check valve 121, and the second check valve 122 are provided as a safety system, an operation process in the event of an accident will be described with reference to FIG. 4 as follows . As described above, the cooling of the reactor core 111 in the normal operating state as shown in FIG. 3 is performed by the primary coolant C1, which is accommodated in the reactor vessel 113 in the first place. At this time, both the first check valve 121 and the second check valve 122 are in the closed state, so that the core cooling heat exchanger 120 does not operate. In other words, when the normal state of the reactor is normal, the inside of the core cooling heat exchanger 120 is not empty, but a coolant (that is, coolant) of the same material as the primary coolant C1 is filled. In other words, normally, the coolant in the core-cooled heat exchanger 120 does not flow but is merely accommodated, and is maintained in a state having the same temperature condition as that of the third coolant C3 in the isolation vessel 115 .

If the amount of the primary coolant C1 in the vessel is lost due to damage to the reactor vessel 113 at this time, the heat generated in the reactor core 111 can not be sufficiently absorbed by the primary coolant C1 Excessive heat is generated. 4, the primary coolant C1 in the reactor vessel 113 evaporates much more, and the upper space of the reactor vessel 113, that is, the upper side of the liquid coolant primary coolant C1 The pressure is greatly increased due to the vapor of the primary coolant (C1). When the pressure in the upper space of the reactor vessel 113 increases, the first check valve 121 is opened.

The first check valve 121 serves to open and close the communication between the inner space of the reactor protection vessel 114 and the inner space of the reactor vessel 113 as described above. At this time, since the first check valve 121 is opened, the vapor in the reactor vessel 113 is discharged into the reactor protection vessel 114 through the first check valve 121.

The vapor of the primary coolant (C1) discharged into the reactor protection vessel (114) rises upward, and therefore, the upstream end of the core cooling heat exchanger (120), which is in communication with the upper end of the reactor protection vessel . At this time, the core cooling heat exchanger 120 is accommodated in the tertiary coolant C3 in the isolation vessel 115, and the primary coolant C1 vapor introduced into the core cooling heat exchanger 120 Exchanges heat with the tertiary coolant (C3) by the core cooling heat exchanger (120), loses heat and condenses and returns to a low-temperature liquid state.

In addition, the primary coolant (C1) vapor continuously flows into one end of the core cooling heat exchanger (120), so that the pressure in the core cooling heat exchanger (120) also increases. The second check valve 122 is opened to open when the pressure in the core cooling heat exchanger 120 is increased. Accordingly, when the second check valve 122 is opened, the second check valve 122 is opened to open the core cooling heat exchanger 120 and the inner space of the reactor vessel 113 communicate with each other. Then, the coolant contained in the core cooling heat exchanger 120 can be introduced into the reactor vessel 113. Of course, at this time, the coolant flowing into the reactor vessel 113 is cooled by the coolant originally filled in the core-coolant heat exchanger 120 when the core coolant heat exchanger 120 is not operating normally, And a coolant mixed with the primary coolant (C1) that is newly introduced into the core cooling heat exchanger (120) through one end of the core coolant heat exchanger (120) communicated with the upper end of the reactor protection vessel (114). (Accordingly, it is described above that the coolant filled in the core-cooled heat exchanger 120 is preferably made of the same material as the first coolant C1. Of course, in general, , Virtually all of the coolant in the reactor is made of the same material, so this configuration can be realized in most cases very natural and natural.)

As described above, the primary coolant C1 returned through the core cooling heat exchanger 120 is re-introduced into the reactor vessel 113 to be circulated. At this time, as described above, the primary coolant C1 passes through the core-cooling heat exchanger 120, dissipates heat with the tertiary coolant C3, and becomes a low-temperature liquid state. Accordingly, the superheat generated in the reactor core 111 can be sufficiently absorbed again, and the primary coolant C1 is discarded by the third coolant C3 through the circulation process as described above. That is, the primary coolant C1 is continuously circulated continuously through the reactor core 111, the reactor vessel 113, the reactor protection vessel 114 and the core-cooling heat exchanger 120, 111 are discharged to the tertiary coolant (C3), thereby achieving a stable cooling action.

In the case of a safety system that is cooled by discarding heat in a conventional reactor as described above with an external heat sink, the cooling system is operated in the order of the coolant, the heat exchange medium, and the heat sink, in the order of the driven residual heat removal (PRHR) The heat is designed to be discarded. That is, conventionally, the heat absorbed by the coolant is removed through the heat exchange medium once more. However, in the case of the present invention, the heat is designed to be discarded in the order of coolant → heat sink. That is, conventionally, the heat transfer from the coolant to the heat sink is indirectly performed. In the present invention, direct heat transfer is performed from the coolant to the heat sink. Accordingly, the core cooling heat exchanger 120 of the present invention can perform much more efficient cooling than apparatuses for removing residual heat such as the conventional PRHR and the like.

As described above, the first and second check valves 121 and 122 are normally closed, the first check valve 121 is opened, the pressure in the reactor vessel 113 is increased, The opening condition of the 2 check valve 122 is that the pressure in the core cooling heat exchanger 120 increases. When the pressure in the reactor vessel 113 is increased, the pressure in the core cooling heat exchanger 120 also increases naturally. As a result, when the first check valve 121 is opened (even if there is a slight difference) (122) is inevitably opened.

On the other hand, when the heat generated in the reactor core 111 is continuously removed, the nuclear reaction occurs in the reactor core 111 and the heat is not generated any more. The reactor core 113, the reactor protection vessel 114, and the core-cooling heat exchanger 120 are not connected to each other in the reactor core 111, The primary coolant C1 that circulates sequentially becomes gradually cooler and becomes a low temperature state. In this process, the amount of vapor of the primary coolant (C1) evaporated in the reactor vessel (113) gradually decreases, that is, the pressure in the reactor vessel (113) gradually decreases. The first check valve 121 is closed when the pressure in the reactor vessel 113 reaches a pressure lower than a pressure reference value sufficient to open the first check valve 121. [ When the first check valve 121 is closed, the steam of the primary coolant (C1) is no longer introduced into the core cooling heat exchanger (120), so that the pressure in the core coolant heat exchanger (120) The second check valve 122 is also closed.

Since the operations of the first and second check valves 121 and 122 are completely performed by a pressure difference, that is, by a change in environmental conditions, no separate actuator or control means for opening or closing them is necessary not. In other words, if the reactor damage occurs, the reaction starts naturally by the environmental conditions changed by the phenomenon occurring during the reactor damage (increase in the amount of the primary coolant, increase in the pressure in the reactor vessel and the core cooling heat exchanger) The operation is stopped naturally by passive environmental conditions such as a decrease in the amount of the primary coolant vapor, a pressure drop in the reactor vessel and the core cooling heat exchanger, and the like.

As described above, the unmanned reactor 100 according to the present invention can be cooled by the first and second check valves 121 and 122 and the core cooling heat exchanger 120, It is possible to realize a completely unattended reactor which does not require any indication at all.

In addition, the core cooling heat exchanger 120 is provided in the isolation vessel 115 as shown in FIGS. 3 and 4, and has a scale similar to that of the reactor protection vessel 114. That is, the amount of the coolant originally accommodated in the core-cooled heat exchanger 120 is considerably large. On the other hand, as described above, the coolant originally accommodated in the core cooling heat exchanger 120 flows into the reactor vessel 113 when the coolant leakage accident first occurs. In other words, the core cooling heat exchanger 120 can sufficiently perform a role as a core replacement water tank (CMT) of a conventional conventional reactor safety system.

In the meantime, even if the core cooling heat exchanger 120 is additionally provided in the isolation vessel 115, the change in the total volume can be expressed as not big. In other words, in the case of a conventional core make-up water tank (CMT), a separate tank for accommodating the coolant is required, so that the facility required space is further needed. In the present invention, the core cooling heat exchanger 120 serves as a CMT Even so, the amount of additional space is not much.

That is, in the unmanned nuclear reactor according to the present invention, since the space occupied by the core-cooled heat exchanger is not so large, the volume of the nuclear reactor itself can be reduced and a large amount of coolant can be easily supplied at the initial stage of the accident. Two goals of miniaturization of the reactor and improvement of the cooling efficiency can be achieved at the same time.

In addition, the unmanned reactor of the present invention further includes a system for discarding waste heat discarded in the tertiary coolant C3 by the core cooling heat exchanger 120 to the outside, thereby further improving the cooling efficiency. The condensing cooler 130 shown in Figs. 3 and 4 is a device that plays such a role.

The condensing cooler 130 is provided outside the isolation vessel 115 to perform heat exchange between the fluid circulated in the isolation vessel 115 and the external environment. 3 and 4, one end of the condensing cooler 130 is communicated with the upper end of the isolation vessel 115, and the other end is connected to the lower end of the isolation vessel 115. As described above, the superheat generated in the reactor core 111 is absorbed by the primary coolant C1 and discharged to the tertiary coolant C3 through the core coolant heat exchanger 120, and the third coolant C3 When the heat is absorbed, the temperature of the tertiary coolant (C3) also rises. At this point, the tertiary coolant (C3) vapor is also introduced into the condenser cooler (130) through one end communicating with the upper end of the isolation vessel (115) The liquid is condensed into a low-temperature liquid by blowing heat to the outside while passing through the heat exchanger 130. The third coolant (C3) condensed in the low temperature liquid state is recirculated to the isolation vessel (115) through the other end of the condenser cooler (130), and the third coolant (C3) The waste heat accumulated in the first coolant (C1) can be discharged to the outside, so that the third coolant (C3) can ultimately absorb heat discarded from the first coolant (C1) more effectively.

Although not shown in the drawings, a pump for facilitating the circulation of the third coolant (C3) on the flow path of the condensing cooler (130) may be provided in order to smoothly flow the third coolant (C3) into the condenser cooler And a valve or the like may be provided in order to prevent the condensing cooler 130 from being unnecessarily operated normally. The present invention is not limited to the drawings and may be suitably modified as necessary.

In addition, the unmanned reactor 100 of the present invention may further include a rupture cooling water tank 140 as shown in Figs. The rupture cooling water tank 140 is provided in the reactor protection vessel 114 and receives cooling water as a secondary cooling material C2. A rupture cooling water tank 140 is provided at the lower end thereof with a rupture plate (Not shown).

3, the pressure in the reactor protection vessel 114 remains within a predetermined range. In this state, the rupture plate 145 is connected to the secondary coolant C2 in the rupture cooling water tank 140 And serves to close the lower end of the rupture cooling water tank 140 so that the rupture cooling water tank 140 can be received stably. The pressure level in the reactor protection vessel 114 is a pre-designed and known value, so that the rupture plate 145 can be easily designed with materials and configurations capable of withstanding the corresponding level of pressure.

4, when the leakage accident occurs, the first check valve 121 provided in the reactor vessel 113 is opened to discharge the vapor of the primary coolant C1, The pressure within the chamber becomes high. The rupture plate 145 is formed so as to rupture when the pressure in the reactor protection container 114 becomes high, so that the rupture plate 145 ruptures only when the state shown in FIG. The lower end of the ruptured cooling water tank 140 is opened and the secondary coolant C2 in the ruptured cooling water tank 140 is discharged to the reactor protection vessel 114 to further assist the cooling.

At this time, since the secondary coolant C2 is mixed with the primary coolant C1 that eventually leaks or is discharged in the form of vapor, it is preferable that the secondary coolant C2 is made of the same material as the primary coolant C1. As described above, it is very easy for the first and second coolants C1 and C2 to be made of the same material because the coolant used in the reactor is mostly water, that is, coolant.

Although the rupture cooling water tank 140 is shown on the edge of the reactor protection vessel 114, the present invention is not limited thereto. For example, the rupture cooling water tank 140 may be formed at the center of the ceiling of the reactor protection vessel 114. In this case, when the rupture plate 145 is ruptured, By directly pouring down to the outlet 113, direct cooling can be done quickly and effectively.

Figure 5 illustrates the cooling step of the unattended reactor of the present invention over time. As shown in the figure, initially, the coolant originally received in the core cooling heat exchanger 120 is supplied into the reactor vessel 113 (that is, the core cooling heat exchanger 120, as described above, (1) to quickly remove the initial overheating. Thereafter, as described above, the primary coolant C1 evaporated in the reactor vessel 113 is circulated through the core-coolant heat exchanger 120 and the heat is discharged to the tertiary coolant C3, (2). After the cooling of the tertiary coolant C3 by the absorption of waste heat has been performed to a certain extent, the heat is further dissipated to the outside by the operation of the condensing cooler 130 as described above, .

As shown in the graph of FIG. 5, in the unmanned nuclear reactors of the present invention, safety systems that operate mainly by time are different from each other (1) operation of a core cooling heat exchanger serving as a CMT in a time zone, (3) operation of discharging heat to the outside by a condensing cooler in a time zone), each safety system plays an optimized role in the state characteristic of each time zone (1) (2) cooling gradually and steadily by discarding overheating by heat sink in time zone / (3) complete cooling by discarding residual waste heat to outside in time zone). The stepwise cooling maximizes the cooling efficiency and, as described above, the safety system of the unmanned reactor of the present invention is much simpler than that of the prior art, thereby improving the economical efficiency and the driving performance simultaneously .

In addition, in the case of small reactors as shown in FIGS. 3 and 4, a plurality of reactor protection vessels may be included in one isolation vessel. In this case, So that ultimately, the actual modularization can be completed.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. It goes without saying that various modifications can be made.

100: Unmanned reactor (of the present invention)
111: reactor core 112: reactor output control rod
113: Reactor vessel 114: Reactor vessel
115: Isolation vessel 116: Steam generator
116a: steam tube 116b: water pipe
116c: steam pipe isolation valve 116d: water pipe isolation valve
117: coolant drive pump
120: Core cooling heat exchanger
121: first check valve 122: second check valve
130: condenser cooler
140: rupture cooling water tank 145: rupture plate
C1: Primary coolant
C2: Secondary coolant
C3: tertiary coolant

Claims (4)

Reactor core (111);
A reactor output control rod 112 into which a lower end portion is vertically movably inserted into the reactor core 111;
The reactor core 111 is disposed on the lowermost side and a part of the upper end of the reactor output control rod 112 is exposed to the outside, And a reactor vessel (113) having the reactor output control rod (112) therein;
A reactor protection vessel 114 formed inside the reactor vessel 113 so as to be hermetically sealed from the outside and having a vacuum vessel therein;
An isolation vessel 115 which is formed in a water tank and accommodates cooling water which is a tertiary coolant C3 and is arranged such that the reactor protection vessel 114 is disposed in the cooling water;
The heat exchanger is installed inside the reactor vessel 113 to receive heat from the primary coolant C1 and evaporate the heat exchange medium circulated therein to discharge the heat exchange medium to the steam pipe 116a to operate the turbine, A steam generator 116 for supplying the heat exchange medium to the water supply pipe 116b;
The reactor vessel 113 is provided inside the isolation vessel 115 and has one end communicated with the upper end of the reactor protection vessel 114 and the other end communicated with the lower end of the reactor vessel 113, A core cooling heat exchanger (120) for performing heat exchange between the cooling water of the cooling water channel (120);
A first check valve 121 provided at an upper portion of the reactor vessel 113 for opening and closing the communication between the inner space of the reactor protection vessel 114 and the inner space of the reactor vessel 113;
A second check valve 122 provided at a lower portion of the reactor vessel 113 for opening and closing communication between the other end of the core cooling heat exchanger 120 and the inner space of the reactor vessel 113;
A rupture cooling water tank 140 provided inside the reactor protection vessel 114 for receiving cooling water as a secondary cooling material C2;
A rupture plate 145 provided at a lower end of the rupture cooling water tank 140 and capable of rupture by pressure;
Wherein the reactor is a reactor.
The method of claim 1, wherein the unattended reactor (100)
And the other end is communicated with the lower end of the isolation vessel 115. The fluid flowing inside the isolation vessel 115 and the external environment A condensing cooler 130 for exchanging heat between the condenser 130 and the condenser 130;
Further comprising: a second reactor having a first reactor and a second reactor.
delete The method of claim 1, wherein the unattended reactor (100)
A coolant drive pump 117 provided on the upper side of the reactor vessel 113 for forcibly circulating the primary coolant C1;
Further comprising: a second reactor having a first reactor and a second reactor.

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