JPH08105997A - Liquid metal purification device - Google Patents

Abstract

PURPOSE: To eliminate the clogging of an impurity arresting device and restore the function thereof. CONSTITUTION: When an impurity arresting device 11 is clogged with deposited impurities as a result of a long-term operation, valves 27 and 28 fitted to a liquid-metal feed pipe 13 and a liquid-metal discharge pipe 14 are closed to stop the feed and discharge of liquid-metal. Then, heated gas is supplied from a hot gas feed port 19, and circulated to the pipe 14, a liquid-metal tank 6, the device 11, a cooling device 33 and the pipe 13 in order. The gas is finally, discharged from a hot gas discharge port 20. According to this construction, impurities deposited in the device 11 are melted and collected into a liquid discharge tank 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid metal purifying apparatus for removing impurities from liquid metals such as lithium and sodium used as coolants in facilities such as fast breeder reactors and fusion reactors. .

[0002]

2. Description of the Related Art FIG. 3 shows a conventional liquid metal purifying apparatus.

A pair of partition plates 2 and 3 are provided inside the liquid metal purifying apparatus main body 1 in the shape of a substantially cylindrical container with a space between the upper and lower parts. The upper partition plate 2 and the lower partition plate 3 are provided below the partition plates 2 and 3, respectively. Refrigerant gas outlet header 4 and refrigerant gas inlet header 5 respectively
And the liquid metal tank 6 is formed between the upper and lower partition plates 2 and 3.

A plurality of heat transfer tubes 7 extending in the vertical direction are arranged at intervals in the circumferential direction at positions near the outer wall in the liquid metal tank 6, and both ends of each heat transfer tube 7 are provided with corresponding partition plates. The cooling device 33 is configured by penetrating the second and third passages and communicating with the refrigerant gas inlet header 5 and the refrigerant gas outlet header 4, respectively.

Further, a support plate 9 is arranged inside the liquid metal tank 6 with a gap 8 between the upper partition plate 2 and the support plate 9.
The cylindrical heat insulating material 10 which is located inside each heat transfer tube 7 and extends downward is attached to the outer edge portion of the.

Further, an impurity collecting device such as a cylindrical collecting wire net 11 located inside the heat insulating material 10 is attached to the lower surface of the support plate 9, and the lower end of the collecting wire net 11 is closed by a closing plate 12 or Close with wire mesh.

Further, a liquid metal supply pipe 13 is provided which penetrates the refrigerant gas outlet header 4 and the upper partition plate 2 and communicates between the outside and the gap 8 above the support plate 9 of the liquid metal tank 6. A liquid metal discharge pipe 14 that penetrates the liquid metal supply pipe 13 and the support plate 9 and connects the outside and the inside of the collection wire net 11 is provided.

Reference numeral 15 is a refrigerant gas such as an inert gas such as argon, 16 is a refrigerant gas supply pipe for supplying the refrigerant gas 15 to the refrigerant gas inlet header 5, and 17 is a refrigerant gas 15
For discharging the refrigerant from the refrigerant gas outlet header 4,
18 is a liquid metal such as lithium, sodium, potassium or gallium.

Further, the liquid metal discharge pipe 14 is provided with a large number of through holes (not shown) in a portion inside the collecting wire net 11.

The above-mentioned liquid metal purifying apparatus is attached in the middle of a flow path for circulating the liquid metal 18 in a facility such as a fast breeder reactor or a nuclear fusion reactor.

When removing impurities from the liquid metal 18 such as lithium, sodium, potassium or gallium, first, the liquid metal 18 is introduced into the liquid metal supply pipe 13.

Then, the liquid metal 18 is supplied from the liquid metal supply pipe 13 to the gap 8 between the upper partition plate 2 and the support plate 9 in the liquid metal tank 6, and the gap 8 provides the outer wall and the heat insulating material 10.
Sent to and from.

At this time, when the refrigerant gas 15 made of an inert gas such as argon is supplied from the refrigerant gas supply pipe 16 to the refrigerant gas inlet header 5, the refrigerant gas 15 is passed from the refrigerant gas inlet header 5 to the heat transfer pipe 7. , The temperature of the liquid metal 18 flowing between the outer wall and the heat insulating material 10 from 400 degrees Celsius to 20 degrees Celsius.
The solubility of the liquid metal 18 is reduced to about 0 degree.

After that, the refrigerant gas 15 is taken out from each heat transfer pipe 7 to the refrigerant gas outlet header 4, and is discharged from the refrigerant gas outlet header 4 to the refrigerant gas discharge pipe 17.

On the other hand, the liquid metal 18 whose solubility has been reduced by the refrigerant gas 15 is guided to the inside of the heat insulating material 10 through the lower end of the heat insulating material 10, and is collected inside the heat insulating material 10. After passing through the metal net 11, the liquid metal discharge pipe 14
Sent to the outside.

Since the liquid metal 18 has a reduced solubility, impurities such as oxygen dissolved in the liquid metal 18 adhere to the collecting wire net 11 when passing through the collecting wire net 11. The impurities are collected and removed by producing crystals of the oxide of the liquid metal 18 with the impurities as nuclei.

[0017]

However, the above-mentioned conventional liquid metal purifying apparatus has the following problems.

That is, the temperature of the liquid metal 18 is lowered so that the dissolved oxygen is deposited on the collecting wire net 11.
Owing to long-term operation, oxide crystals grow and clog the catching wire netting 11, resulting in high pressure loss and deterioration of performance.
It causes 1 blockage.

In view of the above situation, it is an object of the present invention to provide a liquid metal purifying apparatus capable of removing the clogging of a collecting wire net and recovering its function.

[0020]

The present invention relates to a liquid metal purifying apparatus in which a temperature lowering device and an impurity collecting device are arranged inside a liquid metal tank to which a liquid metal supply pipe and a liquid metal discharge pipe are connected. The metal supply pipe and the liquid metal discharge pipe are provided with valves for stopping the supply and discharge of the liquid metal, and the liquid metal supply pipe and the liquid metal discharge pipe are arranged so that the gas heated inside the liquid metal tank is opposite to the liquid metal. The present invention relates to a liquid metal purifying apparatus, characterized in that a hot gas discharge port and a hot gas supply port that flow in a direction are respectively formed, and a drainage tank is connected to a liquid metal tank.

In this case, the hot gas discharge port and the hot gas supply port may be connected by a hot gas passage, and a gas supply source, a circulation device and a heating device may be provided in the middle of the hot gas passage. .

[0022]

The operation of the present invention is as follows.

First, the liquid metal enters the liquid metal tank from the liquid metal supply pipe, passes through the liquid metal tank through the temperature lowering device and the impurity collecting device in this order, and is discharged from the liquid metal discharge pipe.

At this time, since the temperature of the liquid metal is lowered by the temperature lowering device and the solubility thereof is lowered, the impurities are deposited in the impurity trapping device and easily removed.

When the impurity collector is clogged with the deposited impurities due to long-term operation, the valves provided in the liquid metal supply pipe and the liquid metal discharge pipe are closed to stop the supply and discharge of the liquid metal, The heated gas is supplied from the hot gas supply port, and the liquid metal discharge pipe, the liquid metal tank, the impurity collecting device, the temperature lowering device, and the liquid metal supply pipe are flowed in this order to discharge the hot gas from the hot gas discharge port. The impurities deposited in the collector are melted and collected in the drainage tank.

As a result, the clogging of the impurity collector is eliminated, and the impurity removing function is restored.

Further, the hot gas discharge port and the hot gas supply port are connected by a hot gas flow passage, and a gas supply source, a circulation device and a heating device are provided in the middle of the hot gas flow passage to reduce the amount of gas. It can be used in circulation.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an embodiment of the present invention.

A pair of partition plates 2 and 3 are provided inside the main body 1 of the liquid metal purifying apparatus in the shape of a substantially cylindrical container and are vertically spaced from each other. Refrigerant gas outlet header 4 and refrigerant gas inlet header 5 respectively
And the liquid metal tank 6 is formed between the upper and lower partition plates 2 and 3.

A plurality of heat transfer tubes 7 extending in the vertical direction are arranged at intervals in the circumferential direction at positions near the outer wall in the liquid metal tank 6, and both ends of each heat transfer tube 7 are provided with corresponding partition plates. The cooling gas inlet header 5 and the refrigerant gas outlet header 4 are communicated with each other by penetrating the second and third portions to form the temperature lowering device 33.

A support plate 9 is disposed inside the liquid metal tank 6 with a gap 8 between the upper partition plate 2 and the support plate 9.
The cylindrical heat insulating material 10 which is located inside each heat transfer tube 7 and extends downward is attached to the outer edge portion of the.

Further, an impurity trapping device such as a cylindrical trapping net 11 located inside the heat insulating material 10 is attached to the lower surface of the support plate 9, and the lower end of the trapping net 11 is closed by a closing plate 12 or. Close with wire mesh.

Further, a liquid metal supply pipe 13 is provided which penetrates the refrigerant gas outlet header 4 and the upper partition plate 2 and communicates between the outside and the gap 8 above the support plate 9 of the liquid metal tank 6. A liquid metal discharge pipe 14 that penetrates the liquid metal supply pipe 13 and the support plate 9 and connects the outside and the inside of the collection wire net 11 is provided.

Reference numeral 15 is a refrigerant gas such as an inert gas such as argon, 16 is a refrigerant gas supply pipe for supplying the refrigerant gas 15 to the refrigerant gas inlet header 5, and 17 is a refrigerant gas 15
For discharging the refrigerant from the refrigerant gas outlet header 4,
18 is a liquid metal such as lithium, sodium, potassium or gallium.

The liquid metal discharge pipe 14 is provided with a large number of through holes (not shown) in a portion inside the collection wire net 11.

In the present invention, in addition to the above, the hot gas supply port 19 is provided in the liquid metal discharge pipe 14, the hot gas discharge port 20 is provided in the liquid metal supply pipe 13, and the hot gas supply port 19 and the hot gas discharge port 19 are provided. Hot gas flow path 2 between the outlets 20
1, a gas supply source 22 such as a gas cylinder that stores an inert gas such as argon, a circulation device 23 such as a blower that circulates the inert gas, and a heating device such as a heater in the middle of the hot gas passage 21. A device 24 is provided.

Incidentally, 27 is a valve provided in the middle of the liquid metal supply pipe 13, 28 is a valve provided in the middle of the liquid metal discharge pipe 14, and 29 and 30 are respectively provided at the inlet and outlet sides of the hot gas passage 21. The valve 31 is a valve provided in the middle of the drain pipe 25, and the valve 32 is attached to the gas supply source 22.

The liquid metal purifying device is attached in the middle of a flow path for circulating the liquid metal 18 in a facility such as a fast breeder reactor or a fusion reactor.

Next, the operation will be described.

In the case of removing impurities from the liquid metal 18 such as lithium, sodium, potassium and gallium, as shown in FIG.
First, the valves 27 and 28 are opened to open the valves 29 to 3 as shown in FIG.
Keep 2 closed.

Then, the liquid metal 18 flowing through the flow path for flowing the liquid metal 18 in a facility such as a fast breeder reactor or a nuclear fusion reactor is first guided to the liquid metal supply pipe 13 to supply the liquid metal. It is supplied from the pipe 13 to the gap 8 between the upper partition plate 2 and the support plate 9 in the liquid metal tank 6, and the gap 8
From the outer wall to the heat insulating material 10.

At this time, when the refrigerant gas 15 made of an inert gas such as argon is supplied from the refrigerant gas supply pipe 16 to the refrigerant gas inlet header 5, the refrigerant gas 15 is passed from the refrigerant gas inlet header 5 to the heat transfer pipe 7. , The temperature of the liquid metal 18 flowing between the outer wall and the heat insulating material 10 from 400 degrees Celsius to 20 degrees Celsius.
The solubility of the liquid metal 18 is reduced to about 0 degree.

After that, the refrigerant gas 15 is taken out from each heat transfer pipe 7 to the refrigerant gas outlet header 4, and is discharged from the refrigerant gas outlet header 4 to the refrigerant gas discharge pipe 17.

On the other hand, the liquid metal 18 whose solubility has been reduced by the refrigerant gas 15 is guided to the inside of the heat insulating material 10 through the lower end of the heat insulating material 10, and is collected inside the heat insulating material 10. After passing through the metal net 11, the liquid metal discharge pipe 14
Is sent to a flow path for circulating the liquid metal 18 in a facility such as a fast breeder reactor or a fusion reactor.

Since the liquid metal 18 has a reduced solubility, impurities such as oxygen dissolved in the liquid metal 18 adhere to the collecting wire net 11 when passing through the collecting wire net 11. The impurities are collected and removed by producing crystals of the oxide of the liquid metal 18 with the impurities as nuclei.

When oxide crystals grow due to long-term operation and the trapping wire netting 11 is clogged, the valves 27 and 28 are closed to stop the supply and discharge of the liquid metal 18 and supply the refrigerant gas 15. Stop draining.

Next, the valves 29 to 32 are opened, the circulation device 23 such as a blower is driven, and an inert gas such as argon is supplied from the gas supply source 22 such as a gas cylinder to the hot gas passage 2.
Send to 1.

Then, the inert gas such as argon is heated by the heating device 24 and then heated by the hot gas supply port 19
Enters the liquid metal discharge pipe 14 and flows backward in the flow path of the liquid metal 18.

That is, the liquid metal discharge pipe 14 enters the liquid metal tank 6, passes through the collecting wire net 11, passes between the heat insulating material 10 and the outer wall, and the upper partition plate 2 and the support plate 9 are connected. Gap 8
After passing through, the liquid metal is supplied to the liquid metal supply pipe 13 and returned from the hot gas discharge port 20 to the hot gas passage 21.

Thereafter, an inert gas such as argon is sent to the hot gas supply port 19 by the circulation device 23 such as a blower and circulates in the above path.

When the inert gas such as argon is circulated, the valve 32 is closed and the supply of the inert gas from the gas supply source 22 is stopped.

In this manner, the inert gas is heated to cause the liquid metal 18 to flow backward, so that the liquid metal 18 containing impurities that has clogged the collecting wire net 11 is blocked.
The fraction melts and flows down onto the lower partition plate 3, and is discharged from the lower partition plate 3 to the drain tank 26 via the drain pipe 25.

As a result, the clogging of the collecting wire net 11 is eliminated and the function of the liquid metal purifying device is restored.

Once the function of the liquid metal purifier is restored,
As described above, restart the operation of the liquid metal purifier,
Impurities are removed from the liquid metal 18.

The present invention is not limited to the above-mentioned embodiment, and the hot gas passage 21 may be an open passage instead of the circulation passage, and other deviates from the gist of the present invention. It goes without saying that various changes can be made within the range not covered.

[0057]

As described above, according to the liquid metal purifying apparatus of the present invention, the excellent effect that the clogging of the impurity trapping device can be removed and the function can be recovered can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic side sectional view of an embodiment of the present invention.

FIG. 2 is an operation diagram when the clogging of the apparatus of FIG. 1 is cleared.

FIG. 3 is a schematic side sectional view of a conventional example.

[Explanation of symbols]

 6 Liquid Metal Tank 11 Impurity Collection Device (Collection Wire Mesh) 13 Liquid Metal Supply Pipe 14 Liquid Metal Discharge Pipe 18 Liquid Metal 19 Hot Gas Supply Port 20 Hot Gas Discharge Port 21 Hot Gas Flow Path 22 Gas Supply Source 23 Circulation Device 24 heating device 26 drainage tank 27, 28 valve 33 temperature lowering device

Claims (2)

[Claims] 1. A liquid metal purifying apparatus in which a temperature lowering device and an impurity collecting device are arranged inside a liquid metal tank connected to a liquid metal supply pipe and a liquid metal discharge pipe, wherein the liquid metal supply pipe and the liquid metal discharge pipe are provided. A valve for stopping the supply and discharge of liquid metal is provided in the liquid metal supply pipe and the liquid metal discharge pipe, and a hot gas discharge port for flowing the gas heated inside the liquid metal tank in the opposite direction to the liquid metal. A liquid metal purifying apparatus, characterized in that hot gas supply ports are formed respectively, and a drainage tank is connected to the liquid metal tank. 2. The liquid according to claim 1, wherein the hot gas discharge port and the hot gas supply port are connected by a hot gas passage, and a gas supply source, a circulation device and a heating device are provided in the middle of the hot gas passage. Metal purifier.