阅读说明：本技术 一种铅铋合金反应堆冷却剂加注装置及方法 (Device and method for filling coolant into lead-bismuth alloy reactor ) 是由 娄芮凡 兰治科 郭靓 李朋洲 卓文彬 李勇 王涛 岳倪娜 王苏豪 舒畅 于 2021-07-20 设计创作，主要内容包括：本发明属于核动力设备装置领域,具体公开了一种铅铋合金反应堆冷却剂加注装置及方法,该加注装置包括铅铋运输单元、熔化加注单元、气体控制单元和过滤单元；铅铋运输单元位于熔化加注单元上方,用于将需熔化加注的铅铋合金块传输至熔化加注单元中；气体控制单元位于熔化加注单元的上部的两侧,气体控制单元与熔化加注单元贯通连接,用于为熔化加注单元提供惰性气体、调节熔化加注单元内的压力；过滤单元位于熔化加注单元的下部,过滤单元与熔化加注单元固定连接,用于过滤铅铋合金冷却剂中的杂质。本发明的加注装置结构简单、熔化效率高,能够有效控制铅铋合金块在罐中的熔化时间、提高铅铋合金冷却剂的纯净度。(The invention belongs to the field of nuclear power equipment, and particularly discloses a device and a method for filling a coolant of a lead-bismuth alloy reactor, wherein the device comprises a lead-bismuth transportation unit, a melting and filling unit, a gas control unit and a filtering unit; the lead bismuth conveying unit is positioned above the melting and filling unit and is used for conveying the lead bismuth alloy block to be melted and filled into the melting and filling unit; the gas control units are positioned at two sides of the upper part of the melting and filling unit, and are communicated with the melting and filling unit and used for providing inert gas for the melting and filling unit and adjusting the pressure in the melting and filling unit; the filtering unit is positioned at the lower part of the melting and filling unit and is fixedly connected with the melting and filling unit and used for filtering impurities in the lead-bismuth alloy coolant. The filling device has the advantages of simple structure and high melting efficiency, and can effectively control the melting time of the lead bismuth alloy block in the tank and improve the purity of the lead bismuth alloy coolant.)

1. A coolant filling device for a lead-bismuth alloy reactor is characterized in that the filling device is positioned on a pool type stack top detachable part (7) of a lead-bismuth reactor device and is fixedly connected with the pool type stack top detachable part (7); the filling device comprises a lead-bismuth conveying unit, a melting filling unit, a gas control unit and a filtering unit; the lead bismuth conveying unit is positioned above the melting and filling unit and is used for conveying the lead bismuth alloy block (1) to be melted and filled into the melting and filling unit; the gas control units are positioned at two sides of the upper part of the melting and filling unit, and are communicated with the melting and filling unit and used for providing inert gas for the melting and filling unit and adjusting the pressure in the melting and filling unit; the filtering unit is positioned at the lower part of the melting and filling unit and is fixedly connected with the melting and filling unit and used for filtering impurities in the lead-bismuth alloy coolant.

2. The lead bismuth alloy reactor coolant filling device according to claim 1, wherein the melting and filling unit comprises a lead bismuth alloy melting tank (8), an injection tank (11) and an electric heating element, the electric heating element is arranged at the bottom of the lead bismuth alloy melting tank (8) and is used for heating and melting the lead bismuth alloy block (1); the injection tank (11) is positioned below the lead bismuth alloy melting tank (8) and is used for containing the liquid lead bismuth alloy melted and filtered by the lead bismuth alloy melting tank (8).

3. The lead bismuth alloy reactor coolant filling device according to claim 2, wherein the lead bismuth alloy melting tank (8) comprises a preheating section and a heating and melting section, the preheating section is positioned above the heating and melting section, and the preheating section is communicated with the heating and melting section; the preheating section is used for storing and preheating the solid lead bismuth alloy block (1), and the heating and melting section is a high-power heating section and is used for melting the lead bismuth alloy block (1).

4. The lead bismuth alloy reactor coolant filling device according to claim 3, wherein the lead bismuth alloy melting tank (8) is of a structure in which the diameter of the tank body is gradually reduced from top to bottom, and the volume of the heating and melting section is smaller than that of the preheating section.

5. The lead bismuth alloy reactor coolant filling device according to claim 3, characterized in that a plurality of baffle structures (10) are arranged in the preheating section of the lead bismuth alloy melting tank (8), and the baffle structures (10) are fixedly connected in the preheating section of the lead bismuth alloy melting tank (8) and are used for prolonging the storage time of the lead bismuth alloy blocks (1) in the preheating section.

6. The lead bismuth alloy reactor coolant filling device according to claim 2, characterized in that the lead bismuth transport unit comprises a lead bismuth conveyor belt (2), and the lead bismuth conveyor belt (2) is positioned above the lead bismuth alloy melting tank (8) and is used for transporting the lead bismuth alloy blocks (1) to be melted and filled into the lead bismuth alloy melting tank (8).

7. The lead bismuth alloy reactor coolant filling device according to claim 2, wherein the gas control unit comprises a gas inlet pipe (3) and a gas outlet pipe (9), the gas inlet pipe (3) and the gas outlet pipe (9) are positioned at two sides of the preheating section of the lead bismuth alloy melting tank (8), and the gas inlet pipe (3) and the gas outlet pipe (9) are both communicated with the lead bismuth alloy melting tank (8).

8. The apparatus for filling a coolant into a lead-bismuth alloy reactor according to claim 7, wherein the inlet pipe (3) is provided at a lower position than the outlet pipe (9).

9. The apparatus of claim 7, wherein the inert gas is nitrogen.

10. The lead-bismuth alloy reactor coolant filling device according to claim 3, wherein the filtering unit comprises a third filtering layer (4), a second filtering layer (5) and a first filtering layer (6); the primary filter layer (6) is positioned at the middle lower part of the inner side of the heating melting section of the lead bismuth alloy melting tank (8), and the primary filter layer (6) is fixedly connected with the lead bismuth alloy melting tank (8); the secondary filter layer (5) is positioned at the bottom of the lead bismuth alloy melting tank (8), and the secondary filter layer (5) is fixedly connected with the lead bismuth alloy melting tank (8); the three-stage filter layer (4) is positioned at a coolant outlet of the injection tank (11) and sleeved on the lead bismuth alloy melting tank (8), and the three-stage filter layer (4) is fixedly connected with the injection tank (11) and the lead bismuth alloy melting tank (8) respectively.

11. The lead bismuth alloy reactor coolant filling device as claimed in claim 10, wherein the primary filter layer (6) is used for filtering large unmelted lead bismuth alloy pieces (1) and large impurities, and the filter mesh diameter is in the range of 3mm-10 mm.

12. The lead bismuth alloy reactor coolant filling device as claimed in claim 10, wherein the secondary filter layer (5) is used for filtering larger oxide impurities in the liquid lead bismuth, and the filter mesh diameter is in the range of 0.5mm-2 mm.

13. The lead bismuth alloy reactor coolant filling device as claimed in claim 01, wherein the third filter layer (4) is used for filtering fine-particle-size oxide particles and impurities in the liquid lead bismuth coolant filled in the filling tank (11), and the filter mesh diameter is in the range of 100 μm-500 μm.

14. The lead bismuth alloy reactor coolant filling device as claimed in claim 10, wherein the material of the primary filter layer 6 and the secondary filter layer (5) is structural stainless steel which is the same as the structural material of the lead bismuth alloy melting tank (8).

15. The lead-bismuth alloy reactor coolant filling device as claimed in claim 10, wherein the material of the third filtering layer (4) is high temperature glass fiber or graphite fiber.

16. A method for filling a lead-bismuth alloy reactor coolant is characterized by comprising the following steps:

step 1, a lead-bismuth alloy block (1) is transmitted to a melting and filling unit through a lead-bismuth transmission unit;

step 2, providing inert gas for the melting and filling unit through the gas control unit, and adjusting the pressure in the melting and filling unit;

step 3, melting the lead-bismuth alloy block (1) into liquid lead-bismuth alloy through a melting and filling unit;

step 4, filtering impurities in the lead bismuth alloy coolant through a filtering unit;

and 5, injecting a lead-bismuth alloy coolant into a reactor loop.

17. The method for filling the lead-bismuth alloy reactor coolant according to claim 16, wherein the step 1 specifically comprises: the lead bismuth alloy block (1) to be melted and filled is placed on a lead bismuth block conveying belt (2) and is conveyed into a lead bismuth alloy melting tank (8) of a melting and filling unit through the lead bismuth block conveying belt (2).

18. The method for filling the lead-bismuth alloy reactor coolant according to claim 16, wherein the step 2 specifically comprises: an air inlet pipe (3) of the gas control unit provides inert gas nitrogen for a lead bismuth alloy melting tank (8) of the melting and filling unit; the pressure in a lead-bismuth alloy melting tank (8) of the melting and filling unit is adjusted by adjusting the gas flow in a gas inlet pipe (3) and a gas outlet pipe (9) of the gas control unit.

19. The method for filling the lead-bismuth alloy reactor coolant according to claim 16, wherein the step 3 specifically comprises: heating and melting the lead-bismuth alloy block (1) in the lead-bismuth alloy melting tank (8) through an electric heating element in the melting and filling unit, and melting the lead-bismuth alloy block (1) into liquid lead-bismuth alloy.

20. The method for filling the lead-bismuth alloy reactor coolant according to claim 16, wherein the step 4 specifically comprises: filtering large lead bismuth alloy blocks (1) which are not melted and large impurities through a primary filtering layer (6); filtering larger oxide impurities in the liquid lead bismuth through a secondary filtering layer (5); the three-stage filter layer (4) is used for filtering oxide particles with fine particle sizes and impurities in the liquid lead bismuth coolant injected into the tank (11).

21. The method for filling the lead-bismuth alloy reactor coolant according to claim 16, wherein the step 5 specifically comprises: the pressure head is provided by the height difference in the lead bismuth alloy melting tank (8) of the melting and filling unit and the gas control unit, and the lead bismuth alloy coolant enters the reactor loop after passing through the three-stage filter layer (4), the two-stage filter layer (5) and the first-stage filter layer (6) of the filter unit.

Technical Field

The invention belongs to the field of nuclear power equipment, and particularly relates to a device and a method for filling a coolant for a lead-bismuth alloy reactor.

Background

During the operation of the lead-bismuth fast reactor and the large-scale lead-bismuth coolant experimental loop device, the melting and filling of the lead-bismuth alloy are very critical steps.

Since the lead bismuth alloy has a high density and a high melting point relative to sodium metal, when the required amount is large, such as a large-scale circuit (a small-scale lead bismuth nuclear power plant, a large-scale experimental circuit, etc.), the lead bismuth alloy is required to have a volume of about 18 to 50m³The transportation and melting of the lead bismuth alloy can be difficult.

Since the lead bismuth alloy is a non-transparent substance, it is difficult to determine the melting time of the lead bismuth alloy block in the can. In addition, before the lead bismuth alloy coolant is injected into the loop system, impurities in the lead bismuth alloy coolant need to be filtered.

Therefore, it is desired to develop a device for filling a lead bismuth alloy coolant, which can effectively solve the above problems.

Disclosure of Invention

The invention aims to provide a device and a method for filling a lead bismuth alloy reactor coolant, wherein the device is simple in structure and high in melting efficiency, and can effectively control the melting time of a lead bismuth alloy block in a tank and improve the purity of the lead bismuth alloy coolant.

The technical scheme for realizing the purpose of the invention is as follows:

a coolant filling device for a lead-bismuth alloy reactor is positioned on a detachable pool type reactor top part of a lead-bismuth reactor device and fixedly connected with the detachable pool type reactor top part; the filling device comprises a lead-bismuth conveying unit, a melting filling unit, a gas control unit and a filtering unit; the lead bismuth conveying unit is positioned above the melting and filling unit and is used for conveying the lead bismuth alloy block to be melted and filled into the melting and filling unit; the gas control units are positioned at two sides of the upper part of the melting and filling unit, and are communicated with the melting and filling unit and used for providing inert gas for the melting and filling unit and adjusting the pressure in the melting and filling unit; the filtering unit is positioned at the lower part of the melting and filling unit and is fixedly connected with the melting and filling unit and used for filtering impurities in the lead-bismuth alloy coolant.

Further, the melting and filling unit comprises a lead bismuth alloy melting tank, an injection tank and an electric heating element, wherein the electric heating element is arranged at the bottom of the lead bismuth alloy melting tank and used for heating and melting a lead bismuth alloy block; the injection tank is positioned below the lead bismuth alloy melting tank and is used for containing the liquid lead bismuth alloy melted and filtered by the lead bismuth alloy melting tank.

Furthermore, the lead bismuth alloy melting tank comprises a preheating section and a heating and melting section, the preheating section is positioned above the heating and melting section, and the preheating section is communicated with the heating and melting section; the preheating section is used for storing and preheating the solid lead bismuth alloy block, and the heating and melting section is a high-power heating section and is used for melting the lead bismuth alloy block.

Furthermore, the lead bismuth alloy melting tank is of a structure that the diameter of the tank body is gradually reduced from top to bottom, and the volume of the heating and melting section is smaller than that of the preheating section.

Furthermore, a plurality of blocking structures are arranged in the preheating section of the lead bismuth alloy melting tank, and the blocking structures are fixedly connected in the preheating section of the lead bismuth alloy melting tank and are used for prolonging the storage time of the lead bismuth alloy blocks in the preheating section.

Further, the lead bismuth conveying unit comprises a lead bismuth block conveying belt, and the lead bismuth block conveying belt is located above the lead bismuth alloy melting tank and used for conveying the lead bismuth alloy blocks to be melted and filled into the lead bismuth alloy melting tank.

Furthermore, the gas control unit comprises an air inlet pipe and an air outlet pipe, the air inlet pipe and the air outlet pipe are located on two sides of the preheating section of the lead bismuth alloy melting tank, and the air inlet pipe and the air outlet pipe are communicated with the lead bismuth alloy melting tank.

Further, the intake pipe is provided at a lower position than the exhaust pipe.

Further, the inert gas is nitrogen.

Further, the filtering unit comprises a third filtering layer, a second filtering layer and a first filtering layer; the primary filter layer is positioned at the middle lower part of the inner side of the heating and melting section of the lead bismuth alloy melting tank and is fixedly connected with the lead bismuth alloy melting tank; the secondary filter layer is positioned at the bottom of the lead bismuth alloy melting tank and is fixedly connected with the lead bismuth alloy melting tank; the third filtering layer is positioned at the coolant outlet of the injection tank and sleeved on the lead bismuth alloy melting tank, and the third filtering layer is respectively fixedly connected with the injection tank and the lead bismuth alloy melting tank.

Furthermore, the primary filter layer is used for filtering large unmelted lead-bismuth alloy blocks and large impurities, and the diameter range of the filter mesh is 3mm-10 mm.

Furthermore, the secondary filter layer is used for filtering larger oxide impurities in the liquid lead bismuth, and the aperture range of the filter screen is 0.5mm-2 mm.

Furthermore, the three-stage filter layer is used for filtering oxide particles with fine particle sizes and impurities in the liquid lead bismuth coolant injected into the tank, and the diameter range of the filter mesh is 100-500 mu m.

Further, the first-stage filter layer and the second-stage filter layer are made of structural stainless steel which is the same as that of the lead-bismuth alloy melting tank.

Furthermore, the material of the third filtering layer is high-temperature glass fiber and graphite fiber.

A method for filling a cooling agent into a lead-bismuth alloy reactor specifically comprises the following steps:

step 1, a lead bismuth alloy block is transmitted to a melting and filling unit through a lead bismuth transportation unit;

step 2, providing inert gas for the melting and filling unit through the gas control unit, and adjusting the pressure in the melting and filling unit;

step 3, melting the lead-bismuth alloy block into liquid lead-bismuth alloy through a melting and filling unit;

step 4, filtering impurities in the lead bismuth alloy coolant through a filtering unit;

and 5, injecting a lead-bismuth alloy coolant into a reactor loop.

Further, the step 1 specifically comprises: and (3) placing the lead-bismuth alloy block to be melted and filled on a lead-bismuth block conveying belt, and conveying the lead-bismuth alloy block to a lead-bismuth alloy melting tank of the melting and filling unit through the lead-bismuth block conveying belt.

Further, the step 2 specifically includes: an air inlet pipe of the gas control unit is used for providing inert gas nitrogen for a lead bismuth alloy melting tank of the melting and filling unit; the pressure in the lead-bismuth alloy melting tank of the melting and filling unit is adjusted by adjusting the gas flow in the gas inlet pipe and the gas outlet pipe of the gas control unit.

Further, the step 3 specifically includes: and heating and melting the lead-bismuth alloy block in the lead-bismuth alloy melting tank by an electric heating element in the melting and filling unit, and melting the lead-bismuth alloy block into liquid lead-bismuth alloy.

Further, the step 4 specifically includes: filtering large unmelted lead-bismuth alloy blocks and large impurities by a primary filter layer; filtering larger oxide impurities in the liquid lead bismuth through a secondary filter layer; and filtering oxide particles with fine particle sizes and impurities in the liquid lead bismuth coolant injected into the tank through a three-stage filter layer.

Further, the step 5 specifically includes: the pressure head is provided by the height difference in the lead bismuth alloy melting tank of the melting and filling unit and the gas control unit, and the lead bismuth alloy coolant enters the reactor loop after passing through the third filtering layer, the second filtering layer and the first filtering layer of the filtering unit.

The invention has the beneficial technical effects that:

1. according to the cooling agent filling device for the lead bismuth alloy reactor, provided by the invention, the air inlet pipe is arranged at the lower position of the exhaust pipe, nitrogen flows in a preheating section of the lead bismuth alloy melting tank in a floating mode from bottom to top by means of self weight, heat of a heating and melting section of the lead bismuth alloy melting tank is brought to the position above the preheating section in the floating flowing process of the nitrogen to preheat a solid lead bismuth alloy block, oxygen in the lead bismuth alloy melting tank is swept in the floating flowing process of the nitrogen, oxidation of liquid lead bismuth alloy in the melting and adding process is reduced, so that the generation of oxide impurities is reduced, and the purity of the cooling agent for the lead bismuth alloy is effectively improved.

2. According to the cooling agent filling device for the lead bismuth alloy reactor, the overall structure of the lead bismuth alloy melting tank is set to be the structure that the diameter of the tank body is gradually reduced from top to bottom, the volume of the heating and melting section is set to be smaller than that of the preheating section, and the melting efficiency of a lead bismuth metal block in the lead bismuth alloy melting tank is effectively improved.

3. According to the coolant filling device for the lead-bismuth alloy reactor, the lead-bismuth alloy is separated according to the volume through the filtering unit, impurities in the coolant are filtered out at the same time, and the purity degree of the coolant injected into a loop is ensured.

4. According to the cooling agent filling device for the lead bismuth alloy reactor, a pressure head is provided for the cooling agent for the lead bismuth alloy through the height difference of the lead bismuth alloy melting tank and the gas control unit, and when the liquid level of the liquid lead bismuth alloy is higher than the height of the injection tank, the cooling agent can be automatically filled into the reactor.

5. The device for filling the cooling agent into the lead-bismuth alloy reactor provided by the invention has simple structure, controls the melting amount and the injection amount of the lead-bismuth alloy by adjusting the speed of the lead-bismuth block conveyor belt, the input amount of the lead-bismuth alloy block, the pressure of the gas in the lead-bismuth alloy melting tank and the electric heating power of the lead-bismuth alloy melting tank, and is reliable, efficient and convenient to maintain and replace.

Drawings

FIG. 1 is a schematic structural diagram of a coolant filling apparatus for a lead-bismuth alloy reactor provided in the present invention;

in the figure: 1. a lead bismuth alloy block; 2. a lead bismuth block conveyor belt; 3. an air inlet pipe; 4. a third filtering layer; 5. a secondary filter layer; 6. a first-stage filter layer; 7. a pool-type heap top removable section; 8. a lead bismuth alloy melting tank; 9. an exhaust pipe; 10. a barrier structure; 11. injecting into a tank;

region a is a high power heating section, i.e., a melt-filled portion.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

As shown in fig. 1, the coolant filling device for a lead-bismuth alloy reactor provided by the invention is used for melting and filtering a large amount of lead-bismuth alloy and then injecting the lead-bismuth alloy into a loop. The filling device is positioned on the pool type pile top detachable part 7 of the lead bismuth reactor device, is fixedly connected with the pool type pile top detachable part 7, and is convenient to maintain and replace. The filling device comprises a lead-bismuth transporting unit, a gas control unit, a melting and filling unit and a filtering unit; the lead bismuth conveying unit comprises a lead bismuth conveying belt 2; the melting and filling unit comprises a lead bismuth alloy melting tank 8, an injection tank 11 and an electric heating element; the gas control unit comprises a gas inlet pipe 3 and a gas outlet pipe 9; the filtering unit comprises a third filtering layer 4, a second filtering layer 5 and a first filtering layer 6.

The lead bismuth conveying unit comprises a lead bismuth block conveying belt 2, and the lead bismuth block conveying belt 2 is located above the lead bismuth alloy melting tank 8 and used for conveying the lead bismuth alloy blocks 1 to be melted and filled into the lead bismuth alloy melting tank 8.

The melting and filling unit comprises a lead bismuth alloy melting tank 8, an injection tank 11 and an electric heating element. The overall structure of the lead bismuth alloy melting tank 8 is a structure in which the diameter of the tank body is gradually reduced from top to bottom, the lead bismuth alloy melting tank 8 comprises a preheating section and a heating and melting section, the preheating section is located above the heating and melting section, and the preheating section is in through connection with the heating and melting section. The preheating section at the upper part is mainly used for storing the solid lead bismuth alloy block 1, inert gas nitrogen is added into the lead bismuth alloy block through a gas control unit, preliminary preheating is carried out on the lead bismuth alloy block 1, and preliminary purging is carried out on oxygen in a lead bismuth alloy melting tank 8; the heating and melting section at the lower part is a high-power heating section and is mainly used for melting the lead bismuth alloy blocks 1, the heating and melting section consumes too long time for melting a large number of lead bismuth alloy blocks 1 and needs too large power, the volume of the heating and melting section is set to be smaller than that of the preheating section, and the melting efficiency of the lead bismuth metal blocks in the lead bismuth alloy melting tank 8 is effectively improved.

The preheating section of the lead bismuth alloy melting tank 8 is internally provided with a plurality of baffle structures 10, and the baffle structures 10 are fixedly connected in the preheating section of the lead bismuth alloy melting tank 8 and are used for prolonging the storage time of the lead bismuth alloy block 1 in the preheating section and effectively prolonging the preheating time of the lead bismuth alloy block 1 in the high-temperature inert gas environment in the preheating section.

The electric heating element is arranged at the bottom of the lead bismuth alloy melting tank 8 and is used for heating and melting the lead bismuth alloy block 1.

The injection tank 11 is positioned below the lead bismuth alloy melting tank 8 and is used for containing the liquid lead bismuth alloy melted and filtered by the lead bismuth alloy melting tank 8.

The working medium in the melting and filling part of the area A in the figure 1 adopts liquid lead-bismuth alloy, the heat source is an electric heating element when the liquid lead-bismuth alloy is injected for the first time, and then the liquid lead-bismuth alloy can be heated by combining nuclear fission energy and the electric heating element.

After the lead bismuth alloy 1 to be melted and poured enters the lead bismuth alloy melting tank 8, preheating is carried out in the process of falling into the bottom of the lead bismuth alloy melting tank 8 under the action of the blocking structure 10. The lead bismuth alloy block 1 entering the bottom is gradually melted by heating of the electric heating element, and finally is injected into a loop through the filtering unit under the action of air pressure and height difference on the structure of the lead bismuth alloy melting tank 8.

The gas control unit comprises an inlet pipe 3 and an outlet pipe 9. Intake pipe 3 and blast pipe 9 are located the both sides of 8 preheating sections of lead bismuth alloy melting tank to intake pipe 3 is located the position that compares blast pipe 9 lower, and in this embodiment, intake pipe 3 is located the bottom of 8 preheating sections of lead bismuth alloy melting tank, and blast pipe 9 is located the top of 8 preheating sections of lead bismuth alloy melting tank. The inlet of the air inlet pipe 3 is connected with a gas transmission system, the outlet of the exhaust pipe 9 is connected with a gas extraction system, the outlet of the air inlet pipe 3 and the inlet of the exhaust pipe 9 are respectively and fixedly connected with the lead bismuth alloy melting tank 8, and the air inlet pipe 3 and the exhaust pipe 9 are both communicated with the lead bismuth alloy melting tank 8.

The gas input in the gas transmission system is inert gas nitrogen which is inert in chemical property, safe under the irradiation condition of the reactor and slightly lighter than air. Through locating intake pipe 3 in the lower position of blast pipe 9 for nitrogen gas gets into the preheating section of lead bismuth alloy melting tank 8 from lower intake pipe 3, and nitrogen gas relies on the dead weight buoyancy to rise to higher blast pipe 9 department, and nitrogen gas floats the heat of the heating section of the in-process of floating in the preheating section of lead bismuth alloy melting tank 8 top below with lead bismuth alloy melting tank 8 and takes the preheating section top to preheat solid-state lead bismuth alloy piece 1. In addition, since oxygen is introduced into the lead bismuth alloy melting tank 8 when the solid lead bismuth alloy ingot 1 is filled, the oxygen activity in the liquid lead bismuth alloy is increased by the oxygen, and the oxygen activity is more than 10^-6A large amount of oxide impurities can be generated, the gas inlet pipe 3 is arranged at the lower position of the gas outlet pipe 9, so that the input direction of nitrogen is set to be a flowing process from bottom to top, the system can be helped to preliminarily sweep oxygen, the oxidation of the liquid lead-bismuth alloy in the melting and adding process is reduced, and the generation of the oxide impurities is effectively reduced.

The filtering unit comprises a third filtering layer 4, a second filtering layer 5 and a first filtering layer 6, and is used for separating the lead bismuth alloy according to the volume and filtering out impurities in the coolant at the same time, so that the purity degree of the coolant injected into the loop is ensured.

The primary filter layer 6 is positioned at the middle lower part of the inner side of the heating and melting section of the lead bismuth alloy melting tank 8, and the primary filter layer 6 is fixedly connected with the lead bismuth alloy melting tank 8 through welding. The primary filter layer 6 is a baffle with pores and is used for blocking the large lead bismuth alloy block 1 which is not melted and large impurities on the baffle in the heating and melting section and continuously heating the lead bismuth alloy block 1 which is not melted. The aperture of the filter screen is specifically determined by the size of the lead-bismuth alloy block, and the aperture range of the filter screen can be 3mm-10 mm.

The secondary filter layer 5 is positioned at the bottom of the lead bismuth alloy melting tank 8, and the secondary filter layer 5 is fixedly connected with the lead bismuth alloy melting tank 8 through a supporting structure welded on the inner wall of the lead bismuth alloy melting tank 8. The secondary filter layer 5 is used for filtering larger oxide impurities in the liquid lead bismuth, and the aperture range of the filter mesh can be 0.5mm-2 mm.

The third-stage filter layer 4 is located at a coolant outlet of the injection tank 11 and sleeved on the lead bismuth alloy melting tank 8, the third-stage filter layer 4 and the injection tank 11 are fixedly connected through a supporting structure welded on the inner wall of the injection tank 11, and the third-stage filter layer 4 and the lead bismuth alloy melting tank 8 are fixedly connected through a supporting structure welded on the outer wall of the lead bismuth alloy melting tank 8. The third filtering layer 4 is used for filtering out oxide particles with fine particle sizes and impurities in the liquid lead bismuth coolant injected into the tank 11, so that the purity of the lead bismuth coolant entering the loop is ensured. The aperture of the filter screen can be determined by the rod bundle spacing of the reactor core and other parts of the reactor device, the flow requirement of the positioning grid plate and the property of the filter system of the reactor system, and the aperture of the filter screen can be in the range of 100-500 μm.

The material of the primary filter layer 6 and the secondary filter layer 5 can be structural stainless steel which is the same as the structural material of the lead bismuth alloy melting tank 8. The material of the third filtering layer 4 can be high-temperature glass fiber, graphite fiber and the like.

A method for filling a cooling agent into a lead-bismuth alloy reactor specifically comprises the following steps:

step 1, transmitting a lead-bismuth alloy block 1 to a melting and filling unit through a lead-bismuth conveying unit

The lead bismuth alloy block 1 to be melted and filled is placed on a lead bismuth block conveying belt 2 and is conveyed to a lead bismuth alloy melting tank 8 of the melting and filling unit through the lead bismuth block conveying belt 2.

Step 2, providing inert gas for the melting and filling unit through the gas control unit, and adjusting the pressure in the melting and filling unit

And an inert gas nitrogen is provided for a lead-bismuth alloy melting tank 8 of the melting and filling unit through an air inlet pipe 3 of the gas control unit. The air inflow and the air outflow of the gas control unit are controlled by adjusting the gas flow in the air inlet pipe 3 and the air outlet pipe 9 of the gas control unit, the pressure in the lead bismuth alloy melting tank 8 is adjusted, and the lead bismuth alloy is ensured to have enough time to meltThe oxygen activity in the cooling agent for forming lead bismuth and the cooling agent for lead bismuth is maintained at 10^-6-10^-7In the meantime.

If coolant needs to be filled into the reactor, the exhaust pipe 9 can be closed, the air inlet pipe 3 is opened at the same time, the lead bismuth alloy melting tank 8 is pressurized, and the lead bismuth alloy coolant is extruded out of the melting and filling unit and then enters the reactor system.

Step 3, melting the lead-bismuth alloy block (1) into liquid lead-bismuth alloy through a melting and filling unit

Heating and melting the lead-bismuth alloy block 1 in the lead-bismuth alloy melting tank (8) through an electric heating element in the melting and filling unit, and melting the lead-bismuth alloy block (1) into liquid lead-bismuth alloy.

The electric heating element can be a heating rod or a heat tracing wire, and the power and the melting time of the lead-bismuth alloy are determined by the specific design size of the device and the specific shape of the lead-bismuth alloy block.

Step 4, filtering impurities in the lead bismuth alloy coolant through a filtering unit

Filtering large unmelted lead bismuth alloy block 1 and large impurities through a primary filter layer 6, and blocking the large unmelted lead bismuth alloy block 1 and the large impurities on a baffle of the primary filter layer 6 in the heating and melting section; filtering larger oxide impurities in the liquid lead bismuth through a secondary filter layer 5; the three-stage filter layer 4 filters oxide particles with fine particle size and impurities in the liquid lead bismuth coolant injected into the tank 11, so that the purity of the lead bismuth coolant entering the loop is ensured.

Step 5, injecting a lead bismuth alloy coolant into a reactor loop

The pressure head is provided by the height difference in the lead bismuth alloy melting tank 8 of the melting and filling unit and the gas control unit, and the lead bismuth alloy coolant enters the reactor loop after passing through the third filtering layer 4, the second filtering layer 5 and the first filtering layer 6 of the filtering unit. When the liquid lead-bismuth alloy liquid level of the melting part is higher than the height of the injection tank 11, the reactor can be automatically filled with the coolant.

In the whole process of filling the cooling agent of the lead-bismuth alloy reactor, the melting rate and the injection amount of the lead-bismuth alloy can be controlled by adjusting the speed of the lead-bismuth block conveyor belt 2, the input amount of the lead-bismuth alloy block 1, the pressure of gas in the lead-bismuth alloy melting tank 8 and the electric heating power of the lead-bismuth alloy melting tank 8. The melting time of the lead-bismuth alloy can be controlled by controlling the injection amount and the heating power of the lead-bismuth alloy coolant.

When the lead bismuth coolant is injected again, the air can be exhausted through the air control unit, and a part of the molten lead bismuth coolant is sucked into the lower part of the lead bismuth alloy melting tank to accelerate the melting rate of the lead bismuth alloy.

The present invention has been described in detail with reference to the drawings and examples, but the present invention is not limited to the examples, and various changes can be made within the knowledge of those skilled in the art without departing from the spirit of the present invention. The prior art can be adopted in the content which is not described in detail in the invention.