Solid state oxygen control device

Abstract

The present invention discloses a solid-state oxygen control device, comprising: a container, a dissolution chamber for placing lead oxide pellets is provided in the container, and an inlet and an outlet respectively connected to the dissolution chamber are provided at both ends of the container; a flow rate regulating unit is provided on the container to control the flow rate of the coolant in the container; and a replenishing mechanism, the replenishing mechanism is connected to the dissolution chamber to replenish the lead oxide pellets for the dissolution chamber. The present invention solves the problem that the current solid-state oxygen control cannot be replenished online through the provision of a replenishing mechanism and a reflux pipeline, realizes high-power oxygen supply to the reactor device and online replenishment of lead oxide pellets, can accurately control the oxygen concentration in the coolant, form a dense oxide film on the steel surface, prevent the lead-based alloy from further penetrating into the steel, play an anti-corrosion role, solve the key technical difficulties of the lead-based fast reactor or ADS system, and ensure the long-term safe operation of the experimental loop and the lead-based fast reactor.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear reactors, and in particular to a solid-state oxygen control device. Background Art

[0002] Since liquid lead-based alloy coolant is highly corrosive to reactor structural materials, oxygen concentration control technology is generally considered to be the most effective means of corrosion protection for liquid metal loops and lead-based fast reactors. It is one of the key equipment to ensure the long-term safe operation of experimental loops and lead-based fast reactors.

[0003] Adjusting the oxygen content in the liquid lead-bismuth alloy is an important means to reduce its corrosion to steel. If a certain concentration of oxygen is dissolved in the lead-bismuth alloy, a dense oxide film can be formed on the wall of the loop pipe, preventing the lead-bismuth alloy from further penetrating into the steel, thus playing an anti-corrosion role. However, the oxygen concentration in the liquid metal must be maintained within a reasonable range. If it exceeds the upper limit, it will cause excessive oxidation, and solid lead and bismuth oxides will precipitate to form oxide residues, polluting the entire liquid metal system, and may cause heat transfer to deteriorate, and even block the pipeline. If the oxygen concentration is too low, then the oxide film protective layer will not be formed on the wall of the loop pipe, making it difficult to play an anti-corrosion role.

[0004] Currently, the mainstream oxygen control methods in the world are gaseous oxygen control technology and solid-state oxygen control technology.

[0005] The so-called gaseous oxygen control is a method of controlling the dissolved oxygen concentration in lead and bismuth by using the physical and chemical reaction of the injected reaction gas. Initially, Ar / H2 / O2 ternary gas was used to achieve oxygen control, in which Ar gas was used as a carrier gas to dilute the H2 or O2 content and reduce the risk of H2 gas explosion. The method of directly injecting hydrogen and oxygen is characterized by simple equipment and operating procedures, both the input and output are gases, there is no solid residue, and the excess oxygen reacts with hydrogen to generate water vapor and flows out from the outlet pipe. At the same time, long-term hydrogen injection can be used to clean up oxides and restore the thermal hydraulic properties of LBE. However, this method has very strict requirements on the design and adjustment of the pressure and seal of the inlet pipe, and it is almost impossible to directly inject gas with an oxygen content of dozens of ppb.

[0006] It is precisely because traditional gaseous oxygen control technology has many shortcomings that the research on solid oxygen control technology is gradually receiving widespread attention. Solid oxygen control technology mainly controls the dissolution and precipitation of solid oxides to achieve efficient, rapid and clean regulation of the oxygen content in liquid lead-bismuth alloy. When the liquid lead-bismuth alloy flows over the surface of lead oxide solid particles, since the solubility of solid lead oxide in the lead-bismuth alloy changes with the temperature and flow rate of the lead-bismuth alloy, the dissolution and precipitation of lead oxide in the lead-bismuth alloy can be controlled by controlling the flow rate and temperature of the liquid lead-bismuth alloy flowing over the surface of the lead oxide solid particles, thereby achieving the purpose of controlling the oxygen concentration in the lead-bismuth alloy.

[0007] The existing solid-state oxygen control devices can only be used in experimental loops or static experimental devices, and cannot be used in lead-based reactor devices. At the same time, the existing solid-state oxygen control devices cannot be replenished online with lead oxide pellets, which are easily contaminated and "poisoned". The solid-state oxygen control device can only be replaced offline after the reactor is shut down, which will bring radioactive risks to maintenance personnel. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a solid-state oxygen control device capable of supplying lead oxide balls online.

[0009] The technical solution adopted by the present invention to solve the technical problem is: to provide a solid oxygen control device, comprising:

[0010] A container, wherein a dissolution chamber for placing lead oxide pellets is provided in the container, and an inlet and an outlet are provided at both ends of the container respectively connected to the dissolution chamber;

[0011] a flow rate regulating unit, disposed on the container, to control the flow rate of the coolant in the container; and

[0012] A replenishment mechanism is connected to the dissolution chamber to replenish the dissolution chamber with lead oxide pellets.

[0013] Preferably, the inlet is in a necked shape.

[0014] Preferably, the replenishing mechanism comprises a storage chamber for accommodating lead oxide pellets and a replenishing pipe, and the replenishing pipe is connected between the storage chamber and the container.

[0015] Preferably, the supply mechanism further comprises an isolation valve and an air blowing mechanism for pushing the lead oxide balls, and the isolation valve and the air blowing mechanism are both arranged on the supply pipeline.

[0016] Preferably, the flow rate regulating unit comprises a pump body and a power device connected to drive the pump body to rotate; the pump body extends into the container, and the power device is located outside the container.

[0017] Preferably, a first grid plate is provided in the container to divide the dissolution chamber into a first dissolution chamber for placing lead oxide pellets and a second dissolution chamber for placing aluminum oxide pellets, and the second dissolution chamber is located between the first dissolution chamber and the inlet.

[0018] Preferably, the diameter of the lead oxide ball is 1 mm-10 mm; the diameter of the aluminum oxide ball is the same as that of the lead oxide ball.

[0019] Preferably, a second grid plate and a third grid plate are provided in the container, and the second grid plate is placed on top of the lead oxide pellets in the first dissolution chamber and is located between the outlet and the lead oxide pellets;

[0020] The third grid plate is placed at the bottom of the alumina pellets in the second dissolution chamber, between the inlet and the alumina pellets.

[0021] Preferably, the solid-state oxygen control device further comprises:

[0022] The reflux pipeline has two ends connected to the inlet and outlet of the container respectively.

[0023] The solid-state oxygen control device also includes:

[0024] The heating unit is arranged in the dissolving chamber and controls the dissolution of the lead oxide pellets by heating.

[0025] The beneficial effects of the present invention are as follows: through the arrangement of the replenishment mechanism and the reflux pipeline, the problem that the current solid-state oxygen control cannot be replenished online is solved, high-power oxygen supply to the reactor device and online replenishment of lead oxide pellets are achieved, the oxygen concentration in the coolant can be accurately controlled, a dense oxide film is formed on the surface of the steel, and the lead-based alloy is prevented from further penetrating into the interior of the steel, which plays an anti-corrosion role, solves the key technical difficulties of the lead-based fast reactor or the ADS system, and ensures the long-term safe operation of the experimental loop and the lead-based fast reactor.

[0026] In addition, the problem of lead oxide pellets being easily contaminated and "poisoned" was solved by setting up a reflux pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0028] Figure 1 It is a schematic cross-sectional structure diagram of a solid-state oxygen control device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0030] like Figure 1 As shown, a solid-state oxygen control device according to an embodiment of the present invention includes a container 10 , a flow rate regulating unit 20 and a replenishing mechanism 30 .

[0031] A dissolution chamber for placing lead oxide pellets 101 is provided in the container 10, and an inlet 11 and an outlet 12 are provided at both ends of the container 10, respectively connected to the dissolution chamber. The coolant (lead-based alloy coolant) enters the dissolution chamber from the inlet 11 and is discharged from the outlet 12. A flow rate regulating unit 20 is provided on the container 10 to control the flow rate of the coolant in the container 10. A replenishment mechanism 30 is connected to the dissolution chamber to replenish the lead oxide pellets 101 online for the dissolution chamber. The lead oxide pellets 100 are mainly lead monoxide.

[0032] The container 10 is a sealed container as a whole, and the coolant is circulated through the inlet 11 and the outlet 12. A space 103 is formed above the dissolution chamber in the container 10 for accommodating argon gas; correspondingly, an interface (not shown) for accessing argon gas is provided on the container 10. The pressure of the argon gas is consistent with the pressure of the reactor cover gas.

[0033] like Figure 1 As shown, in this embodiment, the lower end of the container 10 is open to form an inlet 11, the upper end is closed, and the outlet 12 is arranged on the upper end along the outer periphery. The outlet 12 can be arranged in multiple ways, such as 10-12 outlets 12 of the same diameter are arranged around the upper end of the container 10, so that the coolant with high oxygen concentration can be discharged in time.

[0034] The inlet 11 is in a constricted shape; the flow velocity at the constricted part is faster and the pressure is lower than the pressure at the outlet 12, so that a part of the high oxygen concentration coolant at the outlet 12 can flow back to the inlet 11 to prevent the lead oxide pellets from being poisoned.

[0035] Furthermore, a first grid plate 51 is provided in the container 10, which divides the dissolution chamber into a first dissolution chamber 101 for placing the lead oxide pellets 100 and a second dissolution chamber 102 for placing the aluminum oxide pellets 200. The second dissolution chamber 102 is located between the first dissolution chamber 101 and the inlet, so that the coolant first passes through the second dissolution chamber 102 after entering the container 10, and then reaches the first dissolution chamber 101 after the flow field is uniform, thereby ensuring that the lead oxide pellets 100 in each area of ​​the first dissolution chamber 101 are uniformly dissolved.

[0036] The diameter of the lead oxide ball 100 is 1 mm to 10 mm; the diameter of the aluminum oxide ball 200 is the same as that of the lead oxide ball 100. Preferably, the aluminum oxide balls 200 are arranged with the same diameter to make the coolant flow field more uniform. The inner diameter of the hole of the first grid plate 51 is smaller than the diameter of the lead oxide ball 100 and the aluminum oxide ball 200 to separate the two balls.

[0037] In addition, a second grid plate 52 and a third grid plate 56 are disposed in the container 10 .

[0038] The second grid plate 52 is placed on the top of the lead oxide pellets 100 in the first dissolution chamber 101, between the outlet 12 and the lead oxide pellets 100, to prevent the lead oxide pellets 100 from escaping from the first dissolution chamber 101. The inner diameter of the pores of the second grid plate 52 is smaller than the diameter of the lead oxide pellets 100.

[0039] The third grid plate 53 is placed at the bottom of the alumina balls 200 in the second dissolution chamber 102, between the inlet 11 and the alumina balls 200, to prevent the alumina balls 200 from running out of the second dissolution chamber 102. The inner diameter of the pores of the third grid plate 53 is smaller than the diameter of the alumina balls 200, to prevent the alumina balls 200 from running out of the second dissolution chamber 102 while ensuring that the coolant passes through the third grid plate 53 with minimal resistance.

[0040] The flow rate regulating unit 20 may include a pump body 21 and a power device 22 connected to drive the pump body 21 to rotate; the pump body 21 extends into the container 10, and the power device 22 is located outside the container 10. In the flow rate regulating unit 20, the flow rate of the coolant is controlled by controlling the rotation speed of the pump body 21, so that the flow rate of the coolant is adjusted by a pump driving method, thereby controlling the oxygen supply rate.

[0041] like Figure 1 As shown, in this embodiment, the pump body 21 is located at the upper end of the first dissolution chamber 101 in the container 10; the power device 22 can be a motor to drive the pump body 21 to rotate.

[0042] The provision of the replenishment mechanism 30 enables online replenishment of the lead oxide pellets 100, without the need for maintenance and overall replacement of the solid oxygen control device, thereby preventing the release of radioactive substances in the coolant. The replenishment mechanism 30 may include a storage chamber 31 for accommodating the lead oxide pellets 100 and a replenishment pipe 32, the replenishment pipe 32 being connected between the storage chamber 31 and the container 10 for the lead oxide pellets 100 to pass through and enter the container 10.

[0043] Specifically, the storage chamber 31 may be located above the first dissolution chamber 101, so that the lead oxide pellets 100 can enter the first dissolution chamber 101 through the supply pipe 32 by gravity. One end of the supply pipe 32 is connected to the storage chamber 31, and the other end is connected to the container 10, which is connected to the first dissolution chamber 101. In addition, since the density of the lead oxide pellets 100 is less than that of the coolant, one end of the supply pipe 32 enters the bottom of the first dissolution chamber 101, which facilitates the supply of the lead oxide pellets 100.

[0044] The supply mechanism 30 further includes an isolation valve 33 and an air blowing mechanism 34 for pushing the lead oxide pellets 100, and both the isolation valve 33 and the air blowing mechanism 34 are arranged on the supply pipeline 32. The isolation valve 33 controls the on-off of the supply pipeline 32. When the lead oxide pellets 100 are not needed to be replenished, the supply pipeline 32 is closed to prevent the release of radioactive substances; when the lead oxide pellets 100 are needed to be replenished, the supply pipeline 32 is opened to replenish the lead oxide pellets 100.

[0045] The blowing mechanism 34 is preferably located between the isolation valve 33 and the storage chamber 31 to push the lead oxide pellets 100 to move into the container 10. The blowing mechanism 34 can also perform gas sealing to prevent the release of radioactive substances when there is no need to push the lead oxide pellets 100 for replenishment.

[0046] When the lead oxide pellets 100 in the first dissolution chamber 101 are reduced as they are dissolved, the supply mechanism 30 replenishes the lead oxide pellets 100 to the first dissolution chamber 101 through a gas rabbit method, which is convenient and effective.

[0047] The solid-state oxygen control device of the present invention further comprises a reflux pipe 40, the two ends of which are respectively connected to the inlet 11 and the outlet 12 of the container, and a part of the high oxygen concentration coolant at the outlet 12 is sent back to the inlet 11 to prevent the lead oxide pellets 101 from being contaminated and poisoned. The openings at both ends of the reflux pipe 40 are respectively connected to the inlet 11 and the outlet 12 of the container 10. Combined with the pressure difference between the inlet 11 and the outlet 12, the reflux pipe 40 passively refluxes a part of the oxygen at the outlet 12 to the inlet 11, so that the Fe ions are oxidized first, and the Fe ions are prevented from being combined on the surface of the lead oxide pellets 100, thereby preventing the lead oxide pellets 100 from being poisoned.

[0048] The reflux pipe 40 may be disposed on the outer wall of the container 10 . There may be one or more reflux pipes 40 , which may be arranged at intervals along the outer circumference of the container 10 .

[0049] Alternatively, the diameter of the return pipe 40 is 5 mm-10 mm.

[0050] Furthermore, the solid-state oxygen control device of the present invention further comprises a heating unit, which is disposed in the first dissolution chamber 101 of the dissolution chamber and controls the dissolution of the lead oxide pellets 100 by heating.

[0051] The heating unit includes at least one heating rod 60; the temperature of the heating rod 60 is controlled to control the dissolution of the lead oxide. The higher the temperature, the faster the lead oxide pellets 100 dissolve, the faster the oxygen supply speed, and the oxygen supply efficiency can be improved.

[0052] The solid-state oxygen control device of the present invention controls the coolant flow rate by heating in combination with pump driving, and can realize high-power oxygen supply to meet the high oxygen consumption rate of the reactor.

[0053] When the solid-state oxygen control device of the present invention is used, it can be directly inserted into the reactor pressure vessel. The lead-based alloy coolant enters the container 10 from the inlet 11, passes through the uniform flow field of the alumina pellets 200 in the second dissolution chamber 102, and then enters the first dissolution chamber 101. The lead oxide pellets 100 in the first dissolution chamber 101 dissolve and supply oxygen, and the oxygen-containing coolant can be output from the outlet 12, and part of it can return to the inlet 11 through the reflux pipe 40.

[0054] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A solid-state oxygen control device, characterized in that: include: A container (10), wherein a dissolution chamber for placing lead oxide pellets (100) is provided in the container (10), and an inlet (11) and an outlet (12) respectively connected to the dissolution chamber are provided at two ends of the container (10); a flow rate regulating unit (20), arranged on the container (10), for controlling the flow rate of the coolant in the container (10); and a replenishing mechanism (30), the replenishing mechanism (30) being connected to the dissolution chamber and replenishing the lead oxide pellets (100) into the dissolution chamber; A reflux pipe (40), wherein two ends of the reflux pipe (40) are respectively connected to an inlet (11) and an outlet (12) of the container (10).

2. The solid-state oxygen control device according to claim 1, characterized in that: The inlet (11) is in a necked shape.

3. The solid-state oxygen control device according to claim 1, characterized in that: The replenishment mechanism (30) comprises a storage chamber (31) for accommodating lead oxide pellets (100) and a replenishment pipe (32), wherein the replenishment pipe (32) is connected between the storage chamber (31) and the container (10).

4. The solid-state oxygen control device according to claim 3, characterized in that: The supply mechanism (30) further comprises an isolation valve (33) and an air blowing mechanism (34) for pushing the lead oxide ball (100); the isolation valve (33) and the air blowing mechanism (34) are both arranged on the supply pipeline (32).

5. The solid-state oxygen control device according to claim 1, characterized in that: The flow rate regulating unit (20) comprises a pump body (21) and a power device (22) connected to drive the pump body (21) to rotate; the pump body (21) extends into the container (10), and the power device (22) is located outside the container (10).

6. The solid-state oxygen control device according to claim 1, characterized in that: A first grid plate (51) is provided in the container (10) to divide the dissolution chamber into a first dissolution chamber (101) for placing lead oxide pellets (100) and a second dissolution chamber (102) for placing aluminum oxide pellets (200); the second dissolution chamber (102) is located between the first dissolution chamber (101) and the inlet (11).

7. The solid-state oxygen control device according to claim 6, characterized in that: The lead oxide ball (100) has a diameter of 1 mm to 10 mm; the aluminum oxide ball (200) has the same diameter as the lead oxide ball (100).

8. The solid-state oxygen control device according to claim 6, characterized in that: A second grid plate (52) and a third grid plate (53) are provided in the container (10); the second grid plate (52) is placed on top of the lead oxide pellets (100) in the first dissolution chamber (101) and is located between the outlet (12) and the lead oxide pellets (100); The third grid plate (53) is placed at the bottom of the alumina balls (200) in the second dissolution chamber (102), and is located between the inlet (11) and the alumina balls (200).

9. The solid-state oxygen control device according to any one of claims 1 to 8, characterized in that: The solid-state oxygen control device also includes: A heating unit is arranged in the dissolution chamber and controls the dissolution of the lead oxide pellets (100) by heating.

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