JP2018151247A - Steam generation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device which generates steam using transuranium element and allows fuel assemblies to be horizontally placed for allowing cooling water to horizontally flow in order to increase the safety in an earthquake.SOLUTION: Transuranium element is used as fuel, and a transuranium element from used fuel is combusted and extinguished. Allowing fuel assemblies to be horizontally placed and arranged to allow cooling water to horizontally flow makes the height of a reactor vessel lower, thereby improving the safety in an earthquake.SELECTED DRAWING: Figure 4

Description

The present invention relates to a boiling water reactor.

FIG. 1 shows an overview of a pressure vessel (10) of a conventional boiling water reactor which is one of steam generation facilities (Non-patent Document 1).
The low-temperature and low-pressure steam that has finished work in the turbine is converted into water. The water is made into high-temperature and high-pressure unsaturated water and mixed with the water in the coolant space outside the shroud (16) between the pressure vessel (10) wall and the shroud (18) through the water supply pipe (17). The water is accelerated by the coolant circulation pump (25) rotated by the pump motor (24) and enters the lower core plenum (8) in the direction of the arrow from the lower end of the shroud (18).
The lower core plenum (8) is surrounded by the bottom of the pressure vessel (10) and the core support plate (9) and is filled with high temperature and high pressure unsaturated water.
The core support plate (9) supports a nuclear fuel assembly (30) in which nuclear fuel rods are bundled.
Unsaturated water that has entered the lower core plenum (8) enters the lower end of the nuclear fuel assembly (30), absorbs heat from the nuclear fuel rods of the nuclear fuel assembly (30), and part of the liquid water becomes saturated steam. It flows into the upper part as a two-phase flow in which saturated water as a liquid and saturated vapor as a gas coexist.
The two-phase flow in the direction of the dotted arrow containing a large amount of saturated steam flowing out from the upper part of the nuclear fuel assembly (30) and the saturated water in the direction of the arrow from the leakage coolant passage (20) are mixed in the mixing region (19). The two-phase flow thus separated into the steam separator 15 is separated into saturated steam rising in the direction of the open arrow and water falling down in the direction of the arrow. Since the raised saturated steam contains some moisture, it is separated by the steam dryer (12) into dried saturated steam rising in the direction of the open arrow and saturated water falling in the direction of the arrow. The dried saturated steam exits from the steam dome (11), through the wall of the pressure vessel (10) and the steam dryer body (13) and from the saturated steam pipe (14) to the turbine.
Control of reactor power is achieved by a cross-shaped control rod (22) that moves up and down by a control rod drive (23).
FIG. 2 is a schematic perspective view of a conventional nuclear fuel assembly (30) containing a nuclear fuel material and a conventional cross-shaped control rod (22). In the nuclear fuel assembly (30), a large number of cylindrical nuclear fuel rods (31) enclosing nuclear fuel material are arranged in a square lattice shape (rarely, a triangular lattice shape), and the lower portion thereof is a lower fuel tie plate ( 40), the bundle of nuclear fuel rods (31) is covered on four sides by a channel box (35) in which a plate made of zirconium alloy or stainless steel is molded into a square frame. The upper end of the fuel rod is inserted into the upper tie plate.
The nuclear fuel assembly (30) is supported by a fuel assembly support fitting (50). Between the nuclear fuel rods (31), there is a main coolant passage (36), and as the cooling water for extracting heat out of the reactor flows from the bottom to the top, it absorbs heat from the fuel rods and becomes steam. It flows as a two-phase flow in which steam and liquid are mixed.
Saturated water flows in the leakage coolant passage (20) between the adjacent nuclear fuel assemblies (30). The cross-shaped control rod (22) can move up and down between the channel boxes (35). The cross-shaped control rod (22) is a hafnium thin plate, which is a strong material that absorbs neutrons for controlling the reactor power. The cross-shaped control rod (22) is moved up and down by a control rod driving device (23) housed in the control rod guide tube (26). Unsaturated water in the lower plenum (8) enters the fuel assembly support fitting (50) from the coolant inlet (99) opened in the control rod guide pipe (26), and then the nuclear fuel assembly ( 30) It flows into the lower end.
The fuel assembly support fitting (50) is supported by a control rod guide tube (26) and a core support plate (9).
The arrows in the figure indicate the main flow direction of the coolant.
FIG. 3 is an overview of a conventional nuclear fuel rod (31). A cladding tube (41) made of a zirconium alloy, which is a cylindrical sheath having a diameter of about 10 mm and a length of 2 m to 4 m, containing helium approximately 10 times the atmospheric pressure, and the upper and lower open ends of the cladding tube (41) are hermetically sealed. The upper end plug (42) and the lower end plug (43) are closed, a number of nuclear fuel pellets (44) loaded in the cladding tube (41), and a spring (45). A nuclear fuel pellet (44) having a diameter of about 8 mm and a length of about 10 mm is formed by sintering an oxide of uranium (also called uranium).
: Corona, author Toko “Atomic Power” 117, 120 pages.

The characteristics of the Fukushima accident were the damage of the building, the second containment vessel, caused by a hydrogen explosion and the resulting rubble peaks. However, the first containment vessel (dry vessel) containing the reactor pressure vessel did not appear to be severely damaged.
Because the building was sealed to a certain extent as a second containment vessel, hydrogen was accumulated. If hydrogen was gradually leaking, the hydrogen explosion may not have occurred.

The building should not be a second containment vessel, but rather be sealed tightly. I want to improve earthquake resistance. Can you reduce things in the building or eliminate beams and scaffolds?
The current BWR increases the reactor power density and makes the nuclear power plant relatively compact. However, the site surrounding the nuclear power generation facility is vast. In that case, it seems likely that a nuclear power generation facility with a low reactor power density will be laid on the entire site area.
Reasons that surface energy is considered safe are: 1: No emissions to the environment. 2: The output density is extremely low. If that is the case, it would be better to make the power density of the nuclear power plant extremely low.
Public opinion is divided into pros and cons for nuclear power. Slightly more anti-nuclear power plants Disposal of spent fuel is a problem.

Means 1 involve a transverse nuclear fuel assembly (130).
The horizontal nuclear fuel assembly (130) includes a large number of TRU nuclear fuel rods (151), each of which includes a large number of cylindrical super uranium element metals embedded in a stainless steel cladding tube (41) in a square lattice pattern. The coolant inlet side is fixed to the fuel inlet side tie plate (140), the coolant outlet side is fixed to the fuel outlet side tie plate (141), and the box (138) of the functional channel box (135) described later is used. Cover the bundle of TRU nuclear fuel rods (151) with four sides,
The functional channel box (135) includes a box (138) obtained by molding a stainless steel plate into a frame having a square cross section, and a low melting point neutron reflecting plate (136) fixed to the bottom surface of the box (138). Further, a neutron absorbing flat plate (137) is fixed to the bottom surface of the low melting point neutron reflecting flat plate (136),
The height H of the square cross section of the box (138) is not less than twice the neutron average moving distance D and not more than D in the box (138) mainly composed of the TRU nuclear fuel rod (151). ) In the flow path direction length L is not less than 3 times and not more than 1 meter of H,
The low melting point neutron reflecting plate (136) is formed by filling a rectangular stainless steel container with a low melting point neutron reflecting material (for example, lead), and the end surface on the cooling water inlet side of the low melting point neutron reflecting plate (136) is frozen by a low melting point metal. And the outlet side end face is covered with stainless steel.
The neutron absorption flat plate (137) is a transverse nuclear fuel assembly (130), which is formed by filling a rectangular stainless steel container with a low melting point neutron absorber (for example, boron carbide (B4C) mixed cadmium (Cd)). ).
The transuranium element (TRU) does not need to be pure and may contain solid fission products (solid FP). It is only necessary to remove volatile substances from the spent fuel. Iron heavy and light elements in solid FP may be mixed.
The low melting point neutron reflector should be lead (melting point 327 ° C, slow neutron macroscopic absorption cross section 0.006 / cm, macroscopic scattering cross section 0.368 / cm). Since the cooling water temperature of the current BWR is about 286 ° C., it melts if the inside of the box (138) becomes hot due to loss of coolant. Neutrons are difficult to absorb because of the small neutron macroscopic cross section, and even if lead melts, there is no effect on the increase or decrease of neutrons. Since the macroscopic scattering cross section is larger than the macroscopic absorption cross section, neutrons that attempt to leak from the box (138) to the bottom are reflected into the box (138).
The frozen seal is covered with a low melting point metal such as lead, tin, cadmium or copper. When it melts at high temperature, the low melting point neutron reflector inside leaks out.
The low melting point neutron reflector to be filled may be lead dioxide (melting point 290 ° C.). Alternatively, lead monoxide (melting point: 886 ° C.) may be added to lead or lead dioxide. Furthermore, water may be used.
The reason why the cover on the outlet side of the neutron absorption flat plate (137) is made of stainless steel is that the steam temperature on the outlet side is likely to rise due to an accident or the like. If the lid melts too sensitively, the facility will shut down even in the event of a chop, and the operating rate will decrease.
As for the boron carbide mixed cadmium which is a low melting point neutron absorber, it is desirable that cadmium be on the low melting point neutron reflecting plate (136) side and be boron carbide below. Boron generates helium gas when it absorbs neutrons, so that the internal pressure of the neutron absorption flat plate (137) rises and may be damaged. Neutron absorption is reduced to cadmium as much as possible to reduce the production of helium as much as possible. Boron absorbs fast neutrons more strongly than cadmium. If a small hole is made in the stainless steel container of the neutron absorption flat plate (137), helium is released to the outside.
The neutron absorption flat plate (137) may be a boron suspension containing boron in stainless steel.

If the height H of the square cross section of the box (138) is less than or equal to D, even if neutrons suddenly increase during operation, neutrons will leak in the height direction, so there will be no sudden increase in neutrons and no rapid increase in output. . On the other hand, if the height H is 2D or more, neutrons are difficult to leak in the height direction. In the unlikely event of a loss of cooling water, if the height H is 2D or less, the water in the leaked cooling water horizontal passage (220) is also lost and the neutron reflection action diminishes, causing neutrons to leak vertically and fissioning The reaction is suppressed.
The average neutron travel distance AVX until neutrons are absorbed is the reciprocal of the macroscopic neutron absorption cross section SIGA. For example, assuming that the steam-cooled neutron energy spectrum is an FBR neutron energy spectrum, the microscopic neutron absorption cross section of plutonium 239 is about 2.3 burns. Then SIGA is about 0.12 / cm, so AVX is about 8cm. In the box (138), there is not only the transuranic element, but there is a cladding pipe (41) and a cooling water passage through which steam passes, so AVX is about 20 cm. If the average neutron travel distance D in the box (138) is AVX, the safety at the time of an accident can be improved.
If the length L in the flow path direction of the box (138) is too short, the linear power density of the TRU nuclear fuel rod (151) becomes large in order to obtain a necessary heat output, which may cause fuel damage. Furthermore, since the rate of leakage of neutrons in the direction L of the flow path direction increases, shielding during normal operation becomes a problem. If L is more than 3 times D, shielding and line power density problems during normal operation are alleviated. However, if L is too long, it would be difficult to manufacture, move or load the horizontal nuclear fuel assembly (130), so the length was set to 1 meter or less.

If the TRU nuclear fuel rod (151) melts in the event of a cooling water loss accident, the low melting point metal in the low melting point neutron reflector (136) of the functional channel box (135) melts and neutron reflection decreases. . As a result, neutrons leak into the neutron absorption plate (137) and are absorbed by the neutron absorption plate (137), so that the fission reaction is suppressed.
If the lower side of the box (138) and the neutron absorption plate (137) are combined in place of the low melting point neutron reflecting plate (136), the lower side of the box (138) is also used. The leakage cooling water horizontal passage (220) is formed, and the same effect as the leakage cooling water horizontal passage (220) on the upper side of the box (138) can be expected.

The means 2 is a flat nuclear reactor characterized by generating steam.
In the flat nuclear reactor, a horizontal nuclear fuel assembly (130) in which the horizontal nuclear fuel assemblies (130) in the means 1 are juxtaposed horizontally in a flat nuclear reactor vessel (103) which is a stainless steel sealed vessel. A rectangular parallelepiped control container (121) is laid between the two.
The water supplied to the inlet plenum (110) from the water supply pipe 1 (161) connected to the upper part of the flat reactor vessel (103) passes through the main water supply horizontal passage (236) of the horizontal nuclear fuel assembly (130). It becomes steam and is discharged to the outlet plenum (111).
The steam ascends in the heat-insulating chimney (123) laid on the top of the flat reactor vessel (103) and is discharged to the outside from the steam pipe 1 (122).
The rectangular parallelepiped control container (121) is a rectangular stainless steel container that can be filled with an aqueous neutron absorber material (for example, sodium pentaborate aqueous solution), and a poison injection tube that injects the neutron absorber aqueous solution into the upper part of the rectangular parallelepiped control container (121). (105) and a poison discharge pipe (107) for discharging the aqueous solution are connected.
A poison storage tank (104) for storing an aqueous solution of neutron absorbing material and a poison discharge tank (106) for discharging the aqueous solution are installed outside the upper side of the flat reactor vessel (103), and an electric pump (108) is installed in each tank. ) Is connected, and the liquid level of the aqueous solution of the neutron absorber in the rectangular parallelepiped control container (121) is adjusted by the electric pump (108).
Electricity can be generated by installing a steam turbine and a condenser at the tip of the flat reactor and rotating the generator with the steam turbine. Cold water from the condenser is led to the water supply pipe 1 (161) and returns to the flat reactor vessel (103). If the feed water returning from the feed water pipe 1 (161) to the inlet plenum (110) is wet steam or saturated steam, saturated steam or superheated steam is discharged from the steam pipe 1 (122).
The high-temperature steam discharged to the outlet plenum (111) is increased in discharge speed due to the chimney effect by the heat insulating chimney (123). As a result, the speed of water flowing into the main feed water horizontal passage (236) of the horizontal nuclear fuel assembly (130) also increases. When the cooling water speed increases, the heat removal action from the TRU nuclear fuel rod (151) increases. If a heat insulating material is wound around the outer periphery of the chimney, the temperature drop of the steam toward the steam turbine can be suppressed.
If an aqueous solution of transuranium element (for example, an aqueous solution of nitrate of transuranium element) is used instead of the aqueous solution of neutron absorber, the safety is improved. When the nuclear fuel in the TRU nuclear fuel rod (151) is burned down and the output is reduced, if an aqueous solution of transuranium element is injected into the rectangular parallelepiped control vessel (121), fission is activated and the output is increased. If TRU is not loaded excessively in the horizontal nuclear fuel assembly (130), the nuclear reaction is naturally reduced by combustion.

Means 3 is a steam generation facility.
The steam generation facility incorporates the flat reactor and emergency diesel generator according to claim 2 in a containment vessel (102).
The containment vessel (102) is a reinforced concrete sealed vessel constructed after the ground surface has been improved.
A solid diluent (210) (for example, cast iron mixed with boron carbide) is laid between the bottom of the containment vessel (102) and the bottom of the flat reactor vessel (103).
In order to operate an electric motor such as the electric pump (108), a power source is required.
The diesel generator (171) is built in a generator room (170) which is a sealed space.
The generator room (170) is connected to the intake side snorkel (173). The diesel generator (171) takes in the air in the generator chamber (170) and operates the diesel engine. Even if the intake-side snorkel (173) is submerged, the diesel generator (171) can be operated by the remaining air in the generator chamber (170) for a short time.
A steam generating facility characterized by laying that the exhaust port of the diesel engine of the diesel generator (171) is directly connected to the exhaust side snorkel (172).
Even if the exhaust-side snorkel (172) is submerged, the diesel generator (171) can be operated if the exhaust pressure is greater than the water pressure.
Prior to ground improvement, prestressed concrete piles, reinforced concrete piles, and concrete-filled steel pipe piles are driven into the ground as ground reinforcement work. After this, the ground will be improved by the deep mixing treatment method. As in the current BWR, the excavation to the bedrock is not carried out and then the reinforcing concrete mat is not applied.
In the Japanese archipelago, which is full of active faults, there are few suitable locations. Even if the power density is reduced and damage is caused by an earthquake with a seismic intensity of about 7, it is sufficient that no fatal event occurs. It is sufficient that the TRU nuclear fuel rod (151) does not melt on a large scale. Even if it is melted, if it is mixed with the solid diluent and the heat generation density is reduced, the influence on the surrounding environment is reduced.
The emergency power supply is snorkeled to prevent loss of emergency power due to seawater flooding from the diesel engine exhaust of the emergency diesel generator. In addition, the ventilation fan outlet has a shutter for rainy weather, but if a sudden flood or tsunami hits when the shutter is open during operation, the shutter will remain open even after operation is stopped. A large amount of water may enter through the shutter.
Instead of the emergency diesel generator, a primary battery or a seawater battery using magnesium may be installed.
Snorkel type with a flood prevention valve is good. It is a snorkel with a flood prevention valve attached to the top of the pipe to prevent flooding from the top of the pipe.
The solid diluent (210) must be solid. If it is liquid (for example, water), there is a risk of vapor explosion due to molten fuel. Since the density of TRU is high, nuclear materials cannot fly far away as experienced in Hiroshima and Nagasaki. It was good that F2 had fallen to the bottom on a recent TV, but he said that if it exploded without falling, it would damage Tokyo (Kunihiko Takeda). Even in Hiroshima and Nagasaki, there are video photographs of streetcars and traffic in a few days. There are few records to report the damage situation of neighboring prefectures.

Means 4 is an all-weather solar power plant.
An all-weather solar power plant by adding a steam turbine, a condenser and a generator to the steam generating facility in means 3 under the solar power plant.
The weak point of solar power generation is that it cannot generate power in rainy weather and at night. To overcome this weakness, a steam generation facility will be laid under the photovoltaic power generation equipment. If the sun is out, you can generate solar power. Below the solar power generation facility is a useless space.
A thermal power generation facility may be laid under the solar power generation facility. Further, a floating body may be floated on the dam lake, and a solar power generation facility or a wind power generation facility may be installed thereon. Since the surface of the dam lake is covered, wasteful evaporation of water can be suppressed, and the occurrence of aquatic can also be suppressed.
If a floating body is floated in the aquaculture farm and a solar power generation system is laid on it, the sunburn of the salmon can be prevented and it becomes a beautiful red coral. If a carp that can be said to be a deep-sea fish tans, it becomes a black carp and cannot be sold.

The functional channel box (135) provides inherent safety against a loss of cooling water accident.
Since the reactor is low in height, it is unlikely that the building will collapse. Therefore, a safe reactor with high earthquake resistance can be expected.
Since the reactor has a low height, the coolant head pressure is almost zero, so no coolant circulation pump is required. The temperature rise of the TRU nuclear fuel rod (151) due to the stagnation of the cooling water is suppressed.
Low line power density operation is good for improving safety. As a result, since the combustion is moderate, it is possible to expect a fuel-free operation for several decades and the management of the reactor is easy.
Because TRU is a powerful spontaneous neutron source, thermal output can be expected even in a subcritical reactor with a neutron source.
Since it is difficult to cause serious accidents, there is no need to drill up to the bedrock, so a low-cost reactor can be constructed in a short time.
By the way, city gas cooling is not suitable for big cities because it promotes the heat island phenomenon due to high exhaust gas temperature. In the case of nuclear power generation in a remote area with few residents, the heat island phenomenon in the remote area is minor.

In order to reduce the accumulated spent nuclear fuel quickly, transuranic elements were used as nuclear fuel, and an inherently high safety reactor could be provided.

FIG. 4 is a schematic view relating to the lateral nuclear fuel assembly (130) of the means 1. A schematic diagram is shown in the lower part. A sectional view is shown in the upper part.
The TRU nuclear fuel rod (151) includes a large number of cylindrical super uranium element metals contained in a stainless steel cladding tube (41).
A large number of TRU nuclear fuel rods (151) are arranged in a square lattice, and the coolant inflow side thereof is fixed to the inlet side tie plate (140), and the coolant outlet side is fixed to the outlet side tie plate (141). .
The inlet side tie plate (140) and the outlet side tie plate (141) are fixed to the following functional channel box (135). Four sides of the bundle of TRU nuclear fuel rods (151) are covered with a box (138) of the functional channel box (135) described below.
In the functional channel box (135), a low melting point neutron reflecting plate (136) is fixed to the bottom surface of a box (138) in which a stainless steel plate is formed into a square frame. Further, a neutron absorbing flat plate (137) is fixed to the bottom surface of the low melting point neutron reflecting flat plate (136).
The low melting point neutron reflecting plate (136) is a rectangular stainless steel container filled with a low melting point neutron reflecting material, and the end surface on the cooling water inlet side of the low melting point neutron reflecting plate (136) is freeze-sealed with a low melting point metal. Has been. The outlet end face is covered with a stainless steel lid.
The neutron absorption flat plate (137) is formed by filling a rectangular stainless steel container with a low melting point neutron absorber. A hafnium plate may be used.
The height H of the square cross section of the functional channel box (135) is not less than the neutron mean free distance D of the TRU nuclear fuel rod (131) but not more than twice the D, and the length of the box (138) in the flow path direction. L is 3 times or more of H and 1 meter or less.
Between adjacent TRU nuclear fuel rods (151) is a main cold water horizontal passage (236) through which a two-phase flow consisting of water liquid and steam passes. Liquid water entering from the inlet tie plate (140) receives heat from the TRU nuclear fuel rod (151) and becomes vapor. Steam exits from the outlet tie plate (141) to the outlet plenum (111).
FIG. 5 is a schematic view of a TRU nuclear fuel rod (151).
The TRU nuclear fuel rod (151) includes a stainless steel cladding tube (41) that is a cylindrical sheath enclosing helium at about atmospheric pressure, and an inlet end plug (airtightly closing the opening end of the cladding tube (41)). 143) and an outlet end plug (142), an end plug spring (146), a number of TRU nuclear fuel pellets (144) loaded in the cladding tube (41), and a plenum spring (145). ing. The TRU nuclear fuel pellet (144) is a transuranium (TRU) metal. Combustion can be moderated if the core of the TRU nuclear fuel pellet (144) is a flammable poison (143). The combustible poison (143) is a mixture of a neutron moderator (for example, silicon carbide) and a neutron absorber (for example, gadolinium).
Insert the end plug (143) of the TRU nuclear fuel rod (151) into the end plug insertion port of the inlet tie plate (140) on the cooling water inflow side, and the outlet end plug (142) on the outlet side of the steam outflow side. It is inserted into the end plug insertion port of the tie plate (141).
The inlet side tie plate (140) is fixed to the cooling water inflow side of the box (138) shown in FIG. The outlet side tie plate (141) is fixed to the steam outlet side of the box (138) shown in FIG. The inlet-side tie plate (140) is provided with an end plug port for inserting the inlet-side end plug (143) and a cooling water inlet for cooling water to flow in.
The outlet side tie plate (141) has an end plug opening for inserting the outlet end plug (142), and a steam outlet for steam (or two-phase flow of steam and water) to flow out. Yes. The TRU nuclear fuel rod (151) is restrained by the inlet tie plate (140) and the outlet tie plate (141) as long as the end plug spring (146) can expand and contract in the length direction.
Several TRU nuclear fuel rods (151) have an inlet end plug (143) and an outlet end plug (142) threaded so that the TRU nuclear fuel rod (151) group is connected to the inlet side tie plate (140). And the outlet side tie plate (141) with a nut.

FIG. 6 is a schematic view relating to the flat reactor of the means 2.
In the flat nuclear reactor, the horizontal nuclear fuel assembly (130) according to claim 1 is arranged in parallel in the flat nuclear reactor vessel (103), which is a sealed vessel made of stainless steel, and is adjacent to the horizontal nuclear fuel assembly (130). ) And a rectangular parallelepiped control container (121).
The water supplied to the inlet plenum (110) from the water supply pipe 1 (161) connected to the upper part of the flat reactor vessel (103) passes through the main water supply horizontal passage (236) of the horizontal nuclear fuel assembly (130). It becomes steam and is discharged to the outlet plenum (111).
The steam ascends in a heat-insulating chimney (123) installed on the upper part of the flat reactor vessel (103) and is discharged to the steam pipe 1 (122) (for example, a steam turbine). The heat insulation chimney (123) is formed by covering the outer periphery of a stainless steel chimney with a heat insulating material.
The rectangular parallelepiped control container (121) is a rectangular stainless steel container that can be filled with an aqueous neutron absorber material (for example, sodium pentaborate aqueous solution), and a poison injection tube that injects the neutron absorber aqueous solution into the upper part of the rectangular parallelepiped control container (121). (105) and a poison discharge pipe (107) for discharging the aqueous solution are connected. If an aqueous solution of neutron absorber is accumulated in the poison discharge pipe (107), this is an aid when the emergency reactor is shut down.
A poison storage tank (104) for storing an aqueous solution of neutron absorbing material and a poison discharge tank (106) for discharging the aqueous solution are installed outside the upper side of the flat reactor vessel (103), and an electric pump (108) is installed in each tank. ) Is connected, and the liquid level of the aqueous solution of the neutron absorber in the rectangular parallelepiped control container (121) is adjusted by the electric pump (108).
A fuel assembly replacement door (120) is provided for each horizontal nuclear fuel assembly (130) at the lengthwise extension of the horizontal nuclear fuel assembly (130) on the side wall of the flat reactor vessel (103). Yes. Originally, the fuel was not exchanged until the decommissioning several decades ahead, but the transverse nuclear fuel assembly (130) could be exchanged in the event of a failure in the transverse nuclear fuel assembly (130).
An inlet side partition plate (112) is laid on the cooling water inlet side of the adjacent horizontal nuclear fuel assembly (130), and an outlet side partition plate (112) is laid on the steam outlet side. ) Enters the main feed horizontal passage (236) of the horizontal nuclear fuel assembly (130). The water leaked mainly into the leakage cooling water horizontal passage (220) at the top of the box (138) is discharged to the outlet plenum (111). If the outlet side partition plate (112) is also provided on the outlet side upper part of the box (138), the water flowing through the leakage cooling water horizontal passage (220) is reduced.
The water in the leakage cooling water horizontal passage (220) serves as a neutron reflector that suppresses excessive leakage of neutrons generated in the horizontal nuclear fuel assembly (130) in the vertical direction.
When the water supply is reduced or lost, the water flowing through the leakage cooling water horizontal passage (220) becomes steam, so that neutrons generated in the horizontal nuclear fuel assembly (130) leak violently in the vertical direction. As a result, the neutron reflection action is reduced and neutrons leak intensely in the vertical direction, so that the nuclear reaction by neutrons is suppressed and the output is reduced.

FIG. 7 is a schematic diagram relating to the steam generation facility of the means 3.
The steam generation facility incorporates the flat reactor and emergency diesel generator according to claim 2 in a containment vessel (102).
The containment vessel (102) is a reinforced concrete sealed vessel constructed after the ground surface has been improved.
The flat reactor vessel (103) is fixed in the containment vessel (102).
A solid diluent (210) (for example, cast iron mixed with boron carbide) is laid between the bottom of the containment vessel (102) and the bottom of the flat reactor vessel (103).
Prestressed concrete piles, reinforced concrete piles and concrete-filled steel pipe piles will be driven into the ground as ground reinforcement work, and ground improvement will be carried out by the deep mixing treatment method. As in the current BWR, the excavation to the bedrock is not carried out and then the reinforcing concrete mat is not applied.
The diesel generator (171) is built in a generator room (170) which is a sealed space.
The generator room (170) is connected to the intake side snorkel (173). The diesel generator (171) sucks air in the generator room (170). Even if the intake-side snorkel (173) is submerged, the diesel generator (171) can be operated for a short time.
The exhaust port of the diesel generator (171) is directly connected to the exhaust side snorkel (172).
Even if the exhaust-side snorkel (172) is submerged, the diesel generator (171) can be operated if the exhaust pressure is greater than the water pressure.
The door 1 is laid on the side wall of the storage container (102) on the side of the water supply pipe 1 (161) so that the equipment can be easily taken in and out.
If the power density is reduced, it is not necessary to install an emergency core cooling system, and the construction cost is greatly reduced. If the top of the steam generating facility is a hydroponics pond or aquaculture pond, emergency cooling water can be secured.
In the Fukushima Tohoku Earthquake, the Fukushima Daiichi site did not cause significant damage from the earthquake itself, but the underground distribution board caused electrical failure due to the subsequent flooding caused by the tsunami. In recent offices, it was disappointing that, due to earthquake resistance, wiring was stopped on the floor and stopped on the ceiling. Failed to “keep cooling for 4 days” until the decay heat of the office decays. Ten years after the Chile earthquake and tsunami where human and material damage occurred, people's memories faded and houses spread in the affected areas. Five years after the Fukushima Tohoku Earthquake, there is a chance to build a city hall again on the land of a certain city hall in Tohoku where 111 people died. The environment where you live every day should be convenient.
In the Awaji Kobe earthquake, the structure directly above the active fault was severely damaged, but the damage was minor if it was 2 meters away from the active fault. The seismic standards for buildings after the Fukushima Tohoku earthquake have become considerably strict.
Even if the nuclear fuel assembly (130) is broken and the nuclear fuel leaks out, the nuclear fuel is mixed with the solid diluent (210), and the heat generated from the leaked nuclear fuel is diluted. Therefore, thermal damage to the artificial ground is reduced.

Electricity can be generated by adding a steam turbine and a generator to the steam generating facility in claim 3. If a steam generation facility is installed under the solar power generation facility, it becomes an all-weather solar power plant that can generate power even in the rain or at night.

The disappearance of spent fuel in the pool can only be achieved with nuclear technology. The potential of producing large quantities of nuclear bombs is likely to be preserved by anti-nuclear people.
Revenue can be expected as TRU disposal costs. The stainless steel of the cladding tube (41) is also profitable if it is recovered from the nuclear power plant.
To respond to people imprinted with surface-derived energy myths, nuclear power generation that is conscious of surface-derived energy will be necessary.
The present invention is a candidate for a power source in an extreme state such as a remote place. For example, it will be a stable energy source and power supply so that fighters can spend comfortably in the camp. The living environment of the camp is important because the period of staying in the camp is longer than the period during which fighters in the battlefield actually meet. As a power source for driving a wooden plywood or cloth or plastic drone, it can be a reactor that can be mounted on a ship, a cargo plane or a truck at any time. Such drones can be produced at low cost and in large quantities as consumables by famous consumer electronics manufacturers and ready-made clothing manufacturers.
Nuclear energy is suitable for global warming countermeasures and energy supply countermeasures. If so, BWR after Fukushima is one of the recipes for energy cocktails (the word “best mix” is not familiar to the general public) (the word “base power” seems to focus on nuclear power for the general public) and adapts to countermeasures for global warming and energy supply. I want to send a safe and comfortable life with absolute unconscious consideration. This requires a new perspective. For example, the energy of the Great East Japan Earthquake is said to be “30,000” for the Hiroshima-type atomic bomb (TNT equivalent 15kt, “160,000 dead”), and what is reported to be “less than 20,000 dead” It is necessary to continue taking out from various angles. It clearly shows the inefficiency of natural energy. It ’s as wasteful as war, but then demands. Recognize the inefficiency of renewable energy generation. There was a person who escaped to Okayama because of the fission product of the nuclear hydrogen explosion in this earthquake (there is a science department at the newspaper company, but trying to give the impression that the nuclear material was scattered) However, if North Korea dropped an atomic bomb on the Sea of Japan, people would really want to escape to Antarctica, so it would be necessary to advertise preparations for transport aircraft and oil carriers. There will be people who can't move, so it will be necessary to promote the preparation of an emergency helicopter. Even at that time, Shimbashi, Shibuya, Shinjuku, Kitashinchi and Hakata will be watching lively electronic bulletin boards. Although we report the delay in recovery six years later as if it were the cause of the nuclear power plant, there is no doubt that the aftermath of the energy release of 30,000 Hiroshima-type atomic bombs can be easily accommodated. It is necessary to publicize the necessity of the nuclear power plant based on the recognition that the press only conveys emotions. The number of Christians will increase in December, and there will be more memorials in March.
Although anti-nuclear public opinion seems to be high, public opinion is easy to relax. Anti-nuclear public opinion can change just as Showa public opinion changed greatly after the defeat. Many of the people and bureaucrats who called intellectuals lived casually unconsciously by looking at the Daitoa mutual prosperity zone unconsciously based on the Meiji version of the unconventional Daiten Constitution. Many of them after the war have lived easy days with unconsciously thinking of democracy, freedom, and equality unconsciously based on the undefeated version of the Constitution. It is not easy to revise the defeated version of the unskilled masters by eliminating the people who gained their social status and gained profits based on the undefeated version of the unskilled masters. It is not easy to convince, but anti-nuclear public opinion can change. Beat the people who want to believe in the riots. When emotions and reason conflict, the emotions generally pass. Nuclear power may be accepted if we talk about eradicating transuranium elements with technology that is as secure as surface-derived energy now that we are in the direction of abolishing nuclear power as an emotion and favoring surface-derived energy.
However, there is a high barrier to the rehabilitation of nuclear power, the product liability law. If there is a product liability law, the manufacturing industry will be contracted and the manufacturing industry will lose its competitiveness. At best, you can only make money with something that is a collection of finished parts. Even parts like air bags are taken responsibility. However, President Trump is trying to implement financial deregulation, but does not mention the relaxation of PL law. There is no expectation of a resurgence in the manufacturing industry in the United States (poor products in Japan, fake from foreign countries), which is obliged to issue the PL Law. The manufacturing industry of a huge system that is improved and developed by repeated trial and error is not feasible. It is difficult to grow a company that “does everything”. In Japan, large manufacturing companies are forced to follow a decline. However, weapons that can be bought with taxes that are the money of others will hold down the responsibility for manufacturing. Only a small manufacturing company that can escape at night will remain. The surplus money from financial deregulation can only go to the military (weapons and soldiers), stocks, land, condominiums and tulips. If the PL Law is gradual for domestic companies and harsh for foreign companies, the possibility of a revival of the manufacturing industry will emerge. From a new business model that has made a lot of money, such as “Please use at your own risk. We are not responsible for any damage caused by using this product. You can use it only after agreeing to the above”. Isn't there reinstatement to the manufacturing model?
There are various problems in the globalization such as the Rockefeller Empire Conspiracy Theory, but in the United States 1st (even though the citizens donated to Yamakoshi Village) Niigata 1st, Tokyo 1st, Setagaya 1st, Minato 1st came, and finally I will be 1st. Disruption of welfare and indifference to the weak. If it becomes 1st competition, it will become deflation competition, and it cannot survive if it does not deflation earlier than others. The fossil fuel price will not rise even if the nuclear power plant is removed. However, fossil fuel soars because when I go to the point where 1st and deflation arrive, there is a return force. You must prepare for it. In the sense of insurance, nuclear power is one of the best technologies for keeping it quiet and quiet in the event that the value of oil increases and soars. Considering households, if electricity charges are apparently reduced with tax subsidies, nuclear power generation will be abolished.
The people of Tokyo, who have become fully liberalized, are not in the eyes of TEPCO, Niigata Prefecture, or Iwate Prefecture. Like the Pokemon epidemic, it was easy for Tokyo people to cool down. Inhabitants of the district who have chosen solar power generation because of the aversion to nuclear power should use expensive solar power generation (the cost of solar power generation is basically the same because other residents are not willing to pay for the purchase of solar power generation). Companies and people are unlikely to enter the ward where the mayor says that it is solar power generation and raises the electricity bill. Next to the ward first, I will be my first, and companies in Japan will not be able to stand up and seek a way of life all over the world. In the end, Japan will become Mizuho, a country rich in nature, including flood disasters. Inhabitants who oppose paying taxes for subsidized places where tsunamis come and return. Due to the possibility that some prefectures will not sell rice in Tokyo, preparations for importing foreign rice proceed (imported from East Asia before the war). We can sympathize with the weak (old people, people with disabilities), but material medical support is almost impossible.
President Trump, who will promote the rise of the coal industry and shale oil by mitigating environmental problems, will dig up quick demand for the activation of the US manufacturing industry. War is the best way to deter huge consumption, but it's scary, so we are trying to create huge consumption by creating a war atmosphere. Be enthusiastic about overreactions in neighboring countries (we can sell weapons and sell fuel for that), and global skirmishes such as the Middle East and East Asia, because of rising oil prices. The increased production of shale oil can be compensated by a reduction in oil production due to sanctions on Iran. Surface-derived energy will be taken in the direction of reduction. As Mike Pence, who is active in nuclear development, became Vice President, the armed forces would increase the value of oil. In order to reduce the possibility of hostile nations and giant terrorist groups collecting micro-enriched uranium and converting it to enrichment or plutonium to make bombs, to reduce nuclear power generation and reduce the micro-enriched uranium market, The US will monopolize the technology to efficiently explode weapon-grade enriched uranium. The technique of the present invention using TRU survives.
On a global scale, there are few plains and it is only near the coast, and in particular, the country of Japan has become mountains and cliffs immediately from the coast. Many people who are electricity consumers live in the plains, so any facility is advantageous near the coast. A rich country like France, which is mostly plain and has a slow-flowing river, is suitable for nuclear power. Germany is unsuitable for nuclear power generation and offshore wind power generation in basically poor countries with forests, lakes, waterways, narrow inland coastlines, few plains, and slow and rivers flowing through several countries. Since it will be difficult to compete if export competitors work on cheap nuclear power generation, it seems that partner countries are actively conducting surface energy propaganda in the same way as Germany. Something happens when coal is dug up. There are iron, hydropower, coal, natural gas and wheat in the countries around Germany. Sweden seems to revive the conscription system (against Russia?).

Schematic of a reactor vessel (2000) containing a void reactivity coefficient negative core loaded with a nuclear fuel mainly composed of a conventional uranium element. Schematic of the reactor cooling facility of the present invention of means 1. Overview of a conventional nuclear fuel rod (31). FIG. 3 is a schematic view relating to a lateral nuclear fuel assembly (130) of the means 1; 1 is a schematic view of a TRU nuclear fuel rod (151). FIG. FIG. 3 is a schematic view relating to a flat reactor of means 2. Schematic concerning the steam generation facility of means 3. FIG.

8 is a core lower plenum.
9 is a core support plate.
10 is a pressure vessel.
11 is a steam dome.
12 is a steam dryer.
13 is a steam dryer trunk.
14 is a saturated steam pipe.
15 is a steam separator.
Reference numeral 16 denotes a coolant space outside the shroud.
17 is a water supply pipe.
18 is a shroud.
19 is a mixing area.
22 is a cross-shaped control rod.
23 is a control rod drive device.
24 is a pump motor.
25 is a coolant circulation pump.
26 is a control rod guide tube.
30 is a nuclear fuel assembly.
31 is a nuclear fuel rod.
35 is a channel box.
40 is a fuel lower tie plate.
41 is a cladding tube.
42 is an upper end plug.
43 is a lower end plug.
44 is a nuclear fuel pellet.
45 is a spring.
102 is a storage container.
103 is a reactor vessel.
104 is a poison storage tank.
105 is a poison injection tube.
106 is a poison discharge tank.
107 is a poison discharge pipe.
108 is an electric pump.
110 is an entrance plenum.
111 is an exit plenum.
112 is an entrance-side partition plate.
Reference numeral 113 denotes an outlet side partition plate.
120 is a fuel assembly replacement door.
121 is a rectangular parallelepiped control container.
122 is a steam pipe 1.
123 is an insulated chimney.
130 is a horizontal nuclear fuel assembly.
135 is a functional channel box.
136 is a low melting point neutron reflecting plate.
137 is a neutron absorption flat plate.
138 is a box.
140 is an inlet side terplate.
141 is an exit side terplate.
142 is an outlet end plug.
143 is an inlet end plug.
144 is a TRU nuclear fuel pellet.
145 is a plenum spring.
146 is an end plug spring.
148 is a flammable poison.
151 is a TRU nuclear fuel rod.
161 is a water supply pipe 1.
170 is a generator room.
171 is a diesel generator.
172 is an exhaust side snorkel.
173 is an intake side snorkel.
210 is a solid diluent.
220 is a leakage cooling water horizontal passage.
236 is a main cooling water horizontal passage.

Claims (4)

The horizontal nuclear fuel assembly (130) includes a large number of TRU nuclear fuel rods (151), each of which includes a large number of cylindrical super uranium element metals embedded in a stainless steel cladding tube (41) in a square lattice pattern. The coolant inlet side is fixed to the fuel inlet side tie plate (140), the coolant outlet side is fixed to the fuel outlet side tie plate (141), and the box (138) of the functional channel box (135) described later is used. Cover the bundle of TRU nuclear fuel rods (151) with four sides,
The functional channel box (135) includes a box (138) obtained by molding a stainless steel plate into a frame having a square cross section, and a low melting point neutron reflecting plate (136) fixed to the bottom surface of the box (138). Further, a neutron absorbing flat plate (137) is fixed to the bottom surface of the low melting point neutron reflecting flat plate (136),
The height H of the square cross section of the box (138) is not less than twice the neutron average moving distance D and not more than D in the box (138) mainly composed of the TRU nuclear fuel rod (151). ) In the flow path direction length L is not less than 3 times and not more than 1 meter of H,
The low melting point neutron reflecting plate (136) is a rectangular stainless steel container filled with a low melting point neutron reflecting material, and the cooling water inlet side end surface of the low melting point neutron reflecting plate (136) is freeze-sealed with a low melting point metal, The outlet side end face is covered with stainless steel,
The lateral nuclear fuel assembly (130) is characterized in that the neutron absorption flat plate (137) is formed by filling and sealing a low melting point neutron absorption reflector in a rectangular stainless steel container. In the flat nuclear reactor, the horizontal nuclear fuel assembly (130) according to claim 1 is arranged in parallel in the flat nuclear reactor vessel (103), which is a sealed vessel made of stainless steel, and is adjacent to the horizontal nuclear fuel assembly (130). ) A rectangular parallelepiped control container (121) between,
The water supplied to the inlet plenum (110) from the water supply pipe 1 (161) connected to the upper part of the flat reactor vessel (103) passes through the main water supply horizontal passage (236) of the horizontal nuclear fuel assembly (130). It becomes steam and is discharged to the outlet plenum (111),
The steam ascends in the adiabatic chimney (123) laid on the top of the flat reactor vessel (103) and is discharged to the outside from the steam pipe 1 (122).
The rectangular parallelepiped control container (121) is a rectangular stainless steel container that can be filled with an aqueous neutron absorber material. The poison injection pipe (105) that injects the neutron absorber aqueous solution into the upper part of the rectangular parallelepiped control container (121) and the aqueous solution are discharged. A poison discharge pipe (107) is connected,
A poison storage tank (104) for storing an aqueous solution of neutron absorbing material and a poison discharge tank (106) for discharging the aqueous solution are installed outside the upper side of the flat reactor vessel (103), and an electric pump (108) is installed in each tank. ) Is connected, and the electric pump (108) is used to adjust the liquid level of the neutron absorber aqueous solution in the rectangular parallelepiped control vessel (121),
A flat nuclear reactor characterized by generating steam. The steam generation facility contains the flat reactor according to claim 2 and the diesel generator (171) for emergency power in the containment vessel (102),
The containment vessel (102) is a sealed container made of reinforced concrete constructed after ground improvement on the ground surface,
A solid diluent (210) is laid between the bottom in the containment vessel (102) and the bottom of the flat reactor vessel (103),
The diesel generator (171) is built in a generator room (170) which is a sealed space, and the generator room (170) is connected to the intake-side snorkel (173), and the diesel engine exhaust port of the diesel generator (171). Is a steam generating facility that is directly connected to the exhaust side snorkel (172). An all-weather solar power plant by adding a steam turbine, a condenser and a generator to the steam generating facility according to claim 3 under the solar power generation facility.

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