Gas injection stirring rapid oxygen reduction device in liquid lead bismuth

Abstract

The invention provides a gas injection and stirring rapid oxygen reduction device in liquid lead bismuth, which comprises a coolant container, a gas injection device, a stirring device and a data acquisition and control system, and is characterized in that reducing gas microbubbles are injected into the liquid lead bismuth in the coolant container, and the bubbles are sheared and dispersed in combination with the stirring device; therefore, full contact and reaction of bubbles and dissolved oxygen are promoted; meanwhile, the gas flow of the gas injection device and the rotating speed of the stirring device are monitored and accurately adjusted in real time through the data acquisition and control system, the dynamic behavior of the oxygen reduction process is optimized, and it is ensured that dissolved oxygen in liquid lead bismuth is efficiently and rapidly removed.

Description

Technical Field

[0001] The present application relates to the field of using liquid metal as a coolant for fourth-generation nuclear reactors, and specifically to a device for a liquid lead-bismuth alloy loop system that realizes rapid oxygen reduction through gas injection stirring. Background Art

[0002] The application of lead-bismuth alloy (Pb: 44.5 wt%, Bi: 55.5 wt%) as a coolant in nuclear reactors has gradually received extensive attention. This alloy has a series of excellent properties, such as low melting point, high boiling point, low neutron absorption cross-section, high spallation neutron production rate, low viscosity, and high thermal conductivity. Compared with other reactor coolants, lead-bismuth alloy has significant advantages in terms of stability and heat conduction performance in high-temperature and high-radiation environments. However, when liquid lead-bismuth alloy contacts structural materials in a reactor, it is prone to a certain degree of dissolution corrosion, threatening the safe operation of the reactor.

[0003] To effectively control the oxygen concentration inside the reactor, it has been found that by precisely regulating the oxygen content in liquid lead-bismuth alloy, a stable oxide film can be formed on the surface of iron-based materials. This film can effectively prevent direct contact and chemical reactions between liquid lead-bismuth and structural materials, thereby significantly reducing the corrosion rate. The gas-phase oxygen control technology has become an effective way to control oxygen concentration. Specifically, it is achieved by injecting oxygen control gas into the liquid lead-bismuth system, controlling the gas composition and injection rate, and then realizing oxidation or reduction through the chemical reaction between the gas and liquid lead-bismuth, and further adjusting the oxygen concentration.

[0004] However, in the implementation of the traditional gas covering injection method, there is an uneven distribution of oxygen concentration. Especially, the diffusion rate of gas in liquid lead-bismuth is slow, resulting in ineffective regulation of the oxygen concentration in local areas, which affects the overall performance and stability of the reactor cooling system. In addition, the reaction efficiency of gas in liquid is low, and the traditional gas injection method often cannot make full use of the contact area between bubbles and liquid, thus affecting the rate and uniformity of the oxygen reduction process.

[0005] Therefore, how to effectively improve the uniformity of oxygen concentration in liquid lead-bismuth and accelerate the reaction rate between bubbles and liquid lead-bismuth has become a technical problem that urgently needs to be solved. Summary of the Invention

[0006] In order to overcome a series of defects existing in the prior art, the purpose of this application is to provide a device for rapidly reducing oxygen by injecting gas and stirring in liquid lead-bismuth in response to the above problems. The device includes a coolant container 1, a gas injection device, a stirring device, and a data acquisition and control system 19. By injecting reducing gas microbubbles into the liquid lead-bismuth in the coolant container 1 and combining with the stirring device to shear and disperse the bubbles, the full contact and reaction between the bubbles and dissolved oxygen are promoted. At the same time, through the data acquisition and control system 19, the gas flow rate of the gas injection device and the rotation speed of the stirring device are monitored in real time and precisely adjusted to optimize the kinetic behavior of the oxygen reduction process and ensure the efficient and rapid removal of dissolved oxygen in the liquid lead-bismuth.

[0007] Further, the coolant container 1 includes a tank body and a flange top cover 20. The tank body and the flange top cover 20 form a sealed space. The bottom of the sealed space is filled with liquid lead-bismuth, and the upper gas space is filled with inert gas. A heater for adjusting the temperature of lead-bismuth is installed outside the tank body, and the control of the heater is realized through a PID temperature control system. The flange top cover 20 is welded with a vacuum pump interface 20-1, a viewing window flange 20-2, an inlet pipe 20-3, an outlet pipe 20-4, an oxygen sensor ferrule interface 20-5, a thermocouple ferrule interface 20-6, a pressure gauge thread interface 20-7, a seal interface flange 20-8, and bolts 20-9 between the tank body flange.

[0008] Further, the gas injection device includes an inert gas cylinder 2, a reducing gas cylinder 3, a first solenoid valve 4, a second solenoid valve 5, a third solenoid valve 6, an intake pipeline 7, an aerator 8, and an outlet pipeline 9. Among them: the first solenoid valve 4 is arranged on the intake pipeline 7 between the inert gas cylinder 2 and the tank body; the second solenoid valve 5 is arranged on the intake pipeline 7 between the reducing gas cylinder 3 and the tank body; the third solenoid valve 6 is arranged on the outlet pipeline 9; the aerator 8 is fixedly connected to the bottom end of the inlet pipe 20-3 and is located at the bottom of the tank body; the intake pipeline 7 is connected to the inlet pipe 20-3, and the outlet pipeline 9 is connected to the outlet pipe 20-4.

[0009] Further, the stirring device includes a stepping motor 10, a magnetic fluid seal 11, a coupling 12, a stirring shaft 13, and a stirring impeller 14. The stepping motor 10 is tightly connected to the magnetic fluid seal 11 in the vertical direction through a central shaft keyway and bottom bolts; the magnetic fluid seal 11 is connected to the stepping motor 10 above it through a central shaft and bolts, and is fixed on the flange top cover 20 below it through a sealing flange 20-8; the coupling 12 connects the central shaft of the magnetic fluid seal 11 to the stirring shaft 13; the stirring impeller 14 is installed on the stirring shaft 13 and is a key component of this device for rapidly reducing oxygen by injecting gas and stirring.

[0010] Furthermore, the data acquisition and control system 19 includes an oxygen sensor 15, a thermocouple 16, a pressure gauge 17, a gas mass flow meter 18 and a control cabinet 19, wherein the oxygen sensor 15 is fixed to the flange top cover 20 through an oxygen sensor ferrule interface 20-5; the thermocouple 16 is fixed to the flange top cover 20 through a thermocouple ferrule interface 20-6; the pressure gauge 17 is fixed to the flange top cover 20 through a pressure gauge threaded interface 20-7; the gas mass flow meter 18 is arranged between the second solenoid valve 5 and the intake pipe 20-3, and is used to accurately control the flow rate of the injected gas; the control cabinet 19 is used for input signal acquisition and output signal control, the input signals include oxygen sensor signals, thermocouple signals, pressure gauge signals, motor speed signals and gas mass flow meter signals, and the signal output control includes gas mass flow control and motor speed control. The gas injection rate is accurately controlled by the gas mass flow meter 18, the aerator 8 is used to generate fine bubbles to increase the gas-liquid contact area, and the gas-liquid dispersion effect is optimized by adjusting the rotation speed of the stepper motor 10, thereby accelerating the consumption rate of the reducing gas reacting with the dissolved oxygen in the liquid lead bismuth, and achieving a rapid reduction in the oxygen concentration in the liquid lead bismuth to the target level.

[0011] Furthermore, the inert gas cylinder 2 is a high-purity argon cylinder; the reducing gas cylinder 3 is an argon-hydrogen mixed gas cylinder; the gas mass flowmeter 18 adopts a high-precision design to display and record the gas mass flow data in real time to ensure accurate control and regulation of the injected gas flow; the stepper motor 10 is a high-temperature resistant, high-torque model, which can drive the central axis of the magnetic fluid seal 11 to rotate, thereby providing stable rotational power for the rotation of the stirring shaft 13; the magnetic fluid seal 11 uses a magnetic fluid cutoff to achieve dynamic sealing of the shaft, ensuring that no solid friction and gas leakage occur when the shaft rotates at high speed.

[0012] Furthermore, the aerator 8 is arranged at a certain distance from the stirring impeller 14 and the oxygen sensor 15 .

[0013] Furthermore, the coupling 12 is made of high temperature and corrosion resistant 316L stainless steel; the stirring shaft 13 and the stirring impeller 14 are both made of 316L stainless steel, which generate strong shear force and impact force through rotation to break and disperse the bubbles, thereby promoting the full mixing of the reducing gas and lead and bismuth.

[0014] Furthermore, the operation method of the liquid lead-bismuth gas injection stirring device comprises the following steps:

[0015] Step S1: When the oxygen concentration in the liquid lead-bismuth alloy exceeds the threshold, start the gas injection device: open the first solenoid valve 4 to inject inert gas into the liquid lead-bismuth; open the third solenoid valve 6 to ensure that the excess gas is discharged through the gas outlet pipe 9; at the same time, continuously monitor the pressure in the tank, and terminate the injection of inert gas and close the first solenoid valve 4 after the pressure reaches the equilibrium state.

[0016] Step S2: Open the second solenoid valve 5, inject reducing gas into the lead-bismuth at the set injection rate, and start the stirring device to stir at the set stirring speed, so that the reducing gas reacts fully with the dissolved oxygen. At the same time, record the oxygen sensing signal, and determine the optimal combination of gas injection rate and stirring speed parameters under the current working conditions by analyzing the oxygen concentration change rate.

[0017] Step S3: When the oxygen sensing signal is stable within the preset target value range, close the stepper motor 10 and the second solenoid valve 5 to complete the entire deoxidation operation.

[0018] Compared with the prior art, the present application has the following beneficial effects:

[0019] The present application integrates the optimized gaseous oxygen control technology with the monitoring and control system, improving the system integrity. Based on the principle of gaseous oxygen control, by injecting reducing gas into the liquid lead-bismuth and combining with the stirring operation, while achieving rapid oxygen reduction, the temperature, pressure, and oxygen concentration changes are monitored and controlled in real time, so that the oxygen concentration is controlled within the range where the Fe 3 O 4 oxide film is stably formed, effectively preventing the corrosion of the structural material by lead-bismuth. The operation is simple, the cost is low, no impurities are generated compared with the traditional oxygen control method, and the oxygen reduction rate is increased, ensuring the stability and efficiency of the oxygen reduction process. This device has application prospects in the corrosion protection of lead-bismuth fast reactors. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of a device for rapid oxygen reduction by gas injection and stirring in liquid lead-bismuth disclosed in the present application;

[0021] Figure 2 It is a schematic structural diagram of the gas injection device and the stirring device in the present application;

[0022] Figure 3 It is a top view of the flange top cover in the present application.

[0023] In the figure:

[0024] 1, coolant container; 2, inert gas cylinder; 3, reducing gas cylinder; 4, first solenoid valve; 5, second solenoid valve; 6, third solenoid valve; 7, intake pipe; 8, aerator; 9, outlet pipe; 10, stepper motor; 11, magneto - fluid seal; 12, coupling; 13, stirring shaft; 14, stirring impeller; 15, oxygen sensor; 16, thermocouple; 17, pressure gauge; 18, gas mass flowmeter; 19, data acquisition and control system; 20, flange top cover

[0025] 20 - 1, vacuum pump interface; 20 - 2, visual window flange; 20 - 3, intake pipe; 20 - 4, outlet pipe; 20 - 5, oxygen sensor ferrule interface; 20 - 6, thermocouple ferrule interface; 20 - 7, pressure gauge thread interface; 20 - 8, seal interface flange; 20 - 9, bolts between tank body flanges Detailed implementation manners

[0026] To make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings in the embodiments of this application. In the drawings, the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions from beginning to end. The described embodiments are some, but not all, of the embodiments of this application.

[0027] All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts fall within the scope of protection of this application.

[0028] The embodiments described below with reference to the drawings and directional terms are exemplary and are intended to explain this application and should not be construed as limiting this application.

[0029] In a broad embodiment of this application, an apparatus for rapid oxygen reduction by gas injection and stirring in liquid lead - bismuth includes a coolant container 1, a gas injection device, a stirring device, and a data acquisition and control system 19. By injecting reducing gas micro - bubbles into the liquid lead - bismuth in the coolant container 1 and combining with the stirring device to shear and disperse the bubbles, the full contact and reaction between the bubbles and dissolved oxygen are promoted. At the same time, the gas flow rate of the gas injection device and the rotation speed of the stirring device are monitored in real - time and precisely adjusted by the data acquisition and control system 19 to optimize the kinetic behavior of the oxygen reduction process and ensure the efficient and rapid removal of dissolved oxygen in the liquid lead - bismuth.

[0030] Furthermore, the coolant container 1 includes a tank body and a flange top cover 20. The tank body and the flange top cover 20 form a sealed space. The bottom of the sealed space is filled with liquid lead-bismuth, and the upper gas space is filled with inert gas. A heater for adjusting the temperature of lead-bismuth is installed outside the tank body, and the heater is controlled by a PID temperature control system. The flange top cover 20 is welded with a vacuum pump interface 20-1, a viewing window flange 20-2, an intake pipe 20-3, an outlet pipe 20-4, an oxygen sensor ferrule interface 20-5, a thermocouple ferrule interface 20-6, a pressure gauge thread interface 20-7, a seal interface flange 20-8, and bolts 20-9 between the tank body flange.

[0031] Furthermore, the gas injection device includes an inert gas cylinder 2, a reducing gas cylinder 3, a first solenoid valve 4, a second solenoid valve 5, a third solenoid valve 6, an intake pipe 7, an aerator 8, and an outlet pipe 9, where: The first solenoid valve 4 is arranged on the intake pipe 7 between the inert gas cylinder 2 and the tank body; the second solenoid valve 5 is arranged on the intake pipe 7 between the reducing gas cylinder 3 and the tank body; the third solenoid valve 6 is arranged on the outlet pipe 9; the aerator 8 is fixedly connected to the bottom end of the intake pipe 20-3 and is located at the bottom of the tank body; the intake pipe 7 is connected to the intake pipe 20-3, and the outlet pipe 9 is connected to the outlet pipe 20-4.

[0032] Furthermore, the stirring device includes a stepping motor 10, a magnetic fluid seal 11, a coupling 12, a stirring shaft 13, and a stirring impeller 14. The stepping motor 10 is tightly connected to the magnetic fluid seal 11 in the vertical direction through a central shaft keyway and bottom bolts; the magnetic fluid seal 11 is connected to the stepping motor 10 above it through a central shaft and bolts, and is fixed on the flange top cover 20 below it through a seal flange 20-8; the coupling 12 connects the central shaft of the magnetic fluid seal 11 to the stirring shaft 13; the stirring impeller 14 is installed on the stirring shaft 13 and is a key component of this gas injection and stirring rapid oxygen reduction device.

[0033] Further, the data acquisition and control system 19 includes an oxygen sensor 15, a thermocouple 16, a manometer 17, a gas mass flowmeter 18, and a control cabinet 19. The oxygen sensor 15 is fixed on the flange top cover 20 through an oxygen sensor ferrule interface 20-5; the thermocouple 16 is fixed on the flange top cover 20 through a thermocouple ferrule interface 20-6; the manometer 17 is fixed on the flange top cover 20 through a manometer threaded interface 20-7; the gas mass flowmeter 18 is arranged between the second solenoid valve 5 and the intake pipe 20-3 for accurately controlling the flow rate of the injected gas; the control cabinet 19 is used for the acquisition of input signals and the control of output signals. The input signals include oxygen sensing signals, thermocouple signals, manometer signals, motor speed signals, and gas mass flowmeter signals. The signal output control includes gas mass flow control and motor speed control. By accurately controlling the gas injection rate through the gas mass flowmeter 18, microbubbles are generated by the aerator 8 to increase the gas-liquid contact area, and the gas-liquid dispersion effect is optimized by adjusting the rotation speed of the stepping motor 10, thereby accelerating the consumption rate of the reaction between the reducing gas and the dissolved oxygen in the liquid lead-bismuth, and rapidly reducing the oxygen concentration in the liquid lead-bismuth to the target level.

[0034] Further, the inert gas cylinder 2 is a high-purity argon gas cylinder; the reducing gas cylinder 3 is an argon-hydrogen mixed gas cylinder; the gas mass flowmeter 18 is designed with high precision to display and record the gas mass flow data in real time to ensure the accurate control and adjustment of the injected gas flow rate; the stepping motor 10 is a high-temperature and high-torque model, which can drive the central shaft of the magnetic fluid seal 11 to rotate, thereby providing stable rotational power for the rotation of the stirring shaft 13; the magnetic fluid seal 11 uses magnetic fluid to achieve dynamic sealing of the shaft, ensuring that there is no solid-solid friction and gas leakage when the shaft rotates at high speed.

[0035] Further, the aerator 8 is arranged at a certain distance from the stirring impeller 14 and the oxygen sensor 15.

[0036] Further, the coupling 12 is made of 316L stainless steel with high temperature and corrosion resistance; the stirring shaft 13 and the stirring impeller 14 are both made of 316L stainless steel, generating strong shear force and impact force through rotation to break and disperse the bubbles, and promoting the full mixing of the reducing gas and lead-bismuth.

[0037] Further, the operation method of the liquid lead-bismuth gas injection and stirring device includes the following steps:

[0038] Step S1: When the oxygen concentration in the liquid lead-bismuth alloy exceeds the threshold, start the gas injection device: open the first solenoid valve 4 to inject inert gas into the liquid lead-bismuth; open the third solenoid valve 6 to ensure that the excess gas is discharged through the gas outlet pipe 9; at the same time, continuously monitor the pressure in the tank, and terminate the injection of inert gas and close the first solenoid valve 4 after the pressure reaches the equilibrium state;

[0039] Step S2: Open the second solenoid valve 5 to inject reducing gas into the lead-bismuth at the set injection rate, and start the stirring device to stir at the set stirring speed, so that the reducing gas reacts fully with the dissolved oxygen. At the same time, record the oxygen sensor signal, and determine the optimal combination of gas injection rate and stirring speed parameters under the current working conditions by analyzing the oxygen concentration change rate;

[0040] Step S3: When the oxygen sensor signal is received and stabilized within the preset target value range, close the stepper motor 10 and the second solenoid valve 5 to complete the entire deoxidation operation.

[0041] The following combines the drawings to list the preferred embodiments of the present application and further describes the present application in detail.

[0042] As Figures 1-3 shown, this embodiment provides a device for rapidly reducing oxygen by gas injection and stirring in liquid lead-bismuth, which includes four parts: a coolant container 1, a gas injection device, a stirring device, and a data acquisition and control system;

[0043] The coolant container 1 includes a tank body and a flange top cover 20. The tank body and the flange top cover 20 form a closed space. The bottom of the closed space is filled with liquid lead-bismuth, and the upper gas space is filled with inert gas; a heater for adjusting the temperature of the lead-bismuth is installed outside the tank body, and the heater is controlled through a PID temperature control system; the flange top cover 20 is welded with a vacuum pump interface 20-1, a viewing window flange 20-2, an air inlet pipe 20-3, an air outlet pipe 20-4, an oxygen sensor ferrule interface 20-5, a thermocouple ferrule interface 20-6, a pressure gauge thread interface 20-7, a seal interface flange 20-8, and bolts 20-9 between the tank body flange;

[0044] The gas injection device includes an inert gas cylinder 2, a reducing gas cylinder 3, a first solenoid valve 4, a second solenoid valve 5, a third solenoid valve 6, an intake pipe 7, an aerator 8, and an outlet pipe 9; the inert gas cylinder 2 is a high-purity argon gas cylinder; the reducing gas cylinder 3 is an argon-hydrogen mixture gas cylinder; the first solenoid valve 4 is arranged on the intake pipe between the inert gas cylinder 2 and the tank body; the second solenoid valve 5 is arranged on the intake pipe between the reducing gas cylinder and the tank body; the third solenoid valve 6 is arranged on the outlet pipe 9; the aerator 8 is fixedly connected to the bottom end of the intake pipe 20-3, located at the bottom of the tank body, and has a certain distance from the stirring impeller 14 and the oxygen sensor 15; the intake pipe 7 is connected to the intake pipe 20-3, and the outlet pipe 9 is connected to the outlet pipe 20-4.

[0045] The stirring device includes a stepper motor 10, a magnetic fluid seal 11, a coupling 12, a stirring shaft 13, and a stirring impeller 14. The stepper motor 10 is tightly connected to the magnetic fluid seal 11 in the vertical direction through a central shaft keyway and bottom bolts; the magnetic fluid seal 11 is connected to the stepper motor 10 above it through a central shaft and bolts, and is fixed to the flange top cover 20 below it through a sealing flange 20-8; the coupling 12 connects the central shaft of the magnetic fluid seal 11 to the stirring shaft 13; the stirring impeller 14 is installed on the stirring shaft 13 and is a key component of this gas injection and stirring rapid oxygen reduction device.

[0046] The data acquisition and control system 19 includes an oxygen sensor 15, a thermocouple 16, a pressure gauge 17, a gas mass flowmeter 18, and a control cabinet 19. The oxygen sensor 15 is fixed to the flange top cover 20 through an oxygen sensor ferrule interface 20-5; the thermocouple 16 is fixed to the flange top cover 20 through a thermocouple ferrule interface 20-6; the pressure gauge 17 is fixed to the flange top cover 20 through a pressure gauge threaded interface 20-7; the gas mass flowmeter 18 is arranged between the second solenoid valve 5 and the intake pipe 20-3 to precisely control the flow rate of the injected gas; the control cabinet 19 is used for the acquisition of input signals and the control of output signals. The input signals include oxygen sensing signals, thermocouple signals, pressure gauge signals, motor speed signals, and gas mass flowmeter signals. The signal output control includes gas mass flow control and motor speed control. By precisely controlling the gas injection rate through the gas mass flowmeter 18, using the aerator 8 to generate fine bubbles to increase the gas-liquid contact area, and optimizing the gas-liquid dispersion effect by adjusting the speed of the stepper motor 10, the consumption rate of the reaction between the reducing gas and the dissolved oxygen in the liquid lead-bismuth is accelerated, and the oxygen concentration in the liquid lead-bismuth is rapidly reduced to the target level.

[0047] The stepper motor 10 is a high-temperature and high-torque model, capable of driving the rotation of the central shaft of the magnetic fluid seal 11, thereby providing stable rotational power for the rotation of the stirring shaft.

[0048] The magnetic fluid seal 11 utilizes magnetic fluid to achieve dynamic sealing of the shaft, ensuring that there is no solid-to-solid friction and gas leakage when the shaft rotates at high speed.

[0049] The coupling 12 is made of 316L stainless steel with high temperature and corrosion resistance.

[0050] Both the stirring shaft 13 and the stirring impeller 14 are made of 316L stainless steel. By rotating, they generate strong shear force and impact force to break and disperse the bubbles, promoting the full mixing of the reducing gas and lead bismuth.

[0051] The gas mass flowmeter 18 is designed with high precision and can display and record the gas mass flow data in real time to ensure precise control and adjustment of the injected gas flow rate.

[0052] Another object of this embodiment is to provide an operation method for the above-mentioned liquid lead bismuth gas injection stirring device, including the following steps:

[0053] Step S1: When the oxygen concentration in the liquid lead bismuth alloy exceeds the threshold, start the gas injection device: open the first solenoid valve 4 to inject inert gas into the liquid lead bismuth; open the third solenoid valve 6 to ensure that the excess gas is discharged through the outlet pipe 9; at the same time, continuously monitor the pressure in the tank, and terminate the injection of inert gas and close the first solenoid valve 4 after the pressure reaches the equilibrium state.

[0054] Step S2: Open the second solenoid valve 5, blow the reducing gas into the lead bismuth at the set injection rate, and start the stirring device to stir at the set stirring speed, so that the reducing gas fully reacts with the dissolved oxygen. At the same time, record the oxygen sensing signal, and determine the optimal combination of gas injection rate and stirring speed parameters under the current working conditions by analyzing the oxygen concentration change rate.

[0055] Step S3: When the oxygen sensing signal stabilizes within the preset target value range, turn off the stepper motor 10 and the second solenoid valve 5 to complete the entire deoxidation operation.

[0056] Furthermore, determining the optimal combination of gas injection rate and stirring speed parameters under the current working conditions by analyzing the oxygen concentration change rate includes the following steps:

[0057] Calculate the change rate based on the oxygen concentration signal Reflect the oxygen consumption rate, and the formula is: where dt represents a small change in time; k represents the proportional relationship between the oxygen concentration change rate and the gas injection rate and stirring speed; represents the influence of the gas injection rate on the oxygen concentration change rate, and α is a fitting parameter used to describe the sensitivity of the gas injection rate to the oxygen concentration change; It shows the influence of the stirring speed on the oxygen concentration change rate, and β is the fitting parameter used to describe the sensitivity of the oxygen concentration change to the stirring speed;

[0058] According to the oxygen concentration change rate, the gas injection rate G is dynamically adjusted through the data acquisition and control system 19 gas and the stirring speed N mix , and the reaction rate is optimized, which is expressed by the formula: where u(t) is the adjustment signal output by the data acquisition and control system 19, which is used to adjust the gas injection rate and the stirring speed so that the oxygen concentration reaches the target value; K p is the proportional gain in the data acquisition and control system 19, which determines the influence degree of the current error on the control signal; e(t) is the error at the current moment, which represents the difference between the target oxygen concentration and the actual oxygen concentration; K i is the integral gain in the data acquisition and control system 19, which controls the cumulative influence of the error and is used to eliminate the long-term steady-state error; K d is the differential gain in the data acquisition and control system 19, which controls the influence of the error change rate and is used to suppress the drastic fluctuation of the error; represents the change rate of the error, that is, the change rate of the error e(t) with time, which is used to evaluate the dynamic change of the error;

[0059] The relationship between the oxygen concentration change rate and different combinations of gas injection rates and stirring speeds is analyzed in real time. When the oxygen concentration change rate reaches the maximum value, the optimal combination of gas injection rate and stirring speed parameters under the current working conditions can be determined.

[0060] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A device for rapid oxygen reduction by gas injection and stirring in liquid lead and bismuth, characterized in that: The invention comprises a coolant container (1), a gas injection device, a stirring device and a data acquisition and control system (19). By injecting reducing gas microbubbles into the liquid lead and bismuth in the coolant container (1), and combining with the stirring device to shear and disperse the bubbles, the bubbles are promoted to fully contact and react with the dissolved oxygen. At the same time, the gas flow rate of the gas injection device and the rotation speed of the stirring device are monitored and accurately adjusted in real time by the data acquisition and control system (19), so as to optimize the kinetic behavior of the oxygen reduction process and ensure the efficient and rapid removal of dissolved oxygen in the liquid lead and bismuth.

2. The device for rapid oxygen reduction by gas injection and stirring in liquid lead and bismuth according to claim 1, characterized in that: The coolant container (1) comprises a tank body and a flange top cover (20), wherein the tank body and the flange top cover (20) form a closed space, wherein the bottom of the closed space is filled with liquid lead bismuth, and the upper air space is filled with inert gas; a heater for adjusting the temperature of the lead bismuth is installed outside the tank body, and the heater is controlled by a PID temperature control system; and a vacuum pump interface (20-1), a visual window flange (20-2), an air inlet pipe (20-3), an air outlet pipe (20-4), an oxygen sensor ferrule interface (20-5), a thermocouple ferrule interface (20-6), a pressure gauge threaded interface (20-7), a sealing interface flange (20-8), and bolts (20-9) between the tank body flanges are welded to the flange top cover (20).

3. The device for rapid oxygen reduction by gas injection and stirring in liquid lead and bismuth according to claim 2, characterized in that: The gas injection device comprises an inert gas cylinder (2), a reducing gas cylinder (3), a first solenoid valve (4), a second solenoid valve (5), a third solenoid valve (6), an air inlet pipe (7), an aerator (8) and an air outlet pipe (9), wherein: the first solenoid valve (4) is arranged on the air inlet pipe (7) between the inert gas cylinder (2) and the tank body; the second solenoid valve (5) is arranged on the air inlet pipe (7) between the reducing gas cylinder (3) and the tank body; the third solenoid valve (6) is arranged on the air outlet pipe (9); the aerator (8) is fixedly connected to the bottom end of the air inlet pipe (20-3) and is located at the bottom of the tank body; the air inlet pipe (7) is connected to the air inlet pipe (20-3), and the air outlet pipe (9) is connected to the air outlet pipe (20-4).

4. The device for rapid oxygen reduction by gas injection and stirring in liquid lead and bismuth according to claim 3, characterized in that: The stirring device comprises a stepper motor (10), a magnetic fluid seal (11), a coupling (12), a stirring shaft (13) and a stirring impeller (14); the stepper motor (10) is tightly connected to the magnetic fluid seal (11) in the vertical direction through a central shaft keyway and bottom bolts; the magnetic fluid seal (11) is connected to the stepper motor (10) above it through a central shaft and bolts, and is fixed to a flange top cover (20) below it through a sealing flange (20-8); the coupling (12) connects the central shaft of the magnetic fluid seal (11) and the stirring shaft (13); and the stirring impeller (14) is installed on the stirring shaft (13).

5. The device for rapid oxygen reduction by gas injection and stirring in liquid lead and bismuth according to claim 4, characterized in that: The data acquisition and control system (19) comprises an oxygen sensor (15), a thermocouple (16), a pressure gauge (17), a gas mass flow meter (18) and a control cabinet (19), wherein the oxygen sensor (15) is fixed on the flange top cover (20) through an oxygen sensor sleeve interface (20-5); the thermocouple (16) is fixed on the flange top cover (20) through a thermocouple sleeve interface (20-6); the pressure gauge (17) is fixed on the flange top cover (20) through a pressure gauge threaded interface (20-7); the gas mass flow meter (18) is arranged between the second solenoid valve (5) and the air intake pipe (20-3) and is used for accurately controlling the flow rate of the injected gas; the control cabinet (19) is used for collecting input signals and controlling output signals, wherein the input signals include oxygen sensor signals, thermocouple signals, pressure gauge signals, motor speed signals and gas mass flow meter signals, and the signal output control includes gas mass flow control and motor speed control. The gas injection rate is precisely controlled by a gas mass flow meter (18), fine bubbles are generated by an aerator (8) to increase the gas-liquid contact area, and the gas-liquid dispersion effect is optimized by adjusting the rotation speed of a stepper motor (10), thereby accelerating the consumption rate of the reducing gas in the liquid lead bismuth by reacting with dissolved oxygen, and achieving a rapid reduction of the oxygen concentration in the liquid lead bismuth to a target level.

6. The device for rapid oxygen reduction by gas injection and stirring in liquid lead and bismuth according to claim 5, characterized in that: The inert gas cylinder (2) is a high-purity argon gas cylinder; the reducing gas cylinder (3) is an argon-hydrogen mixed gas cylinder; the gas mass flow meter (18) is designed with high precision to display and record gas mass flow data in real time to ensure accurate control and regulation of the injected gas flow; the stepper motor (10) is a high-temperature resistant, high-torque model, capable of driving the central axis of the magnetic fluid seal (11) to rotate, thereby providing stable rotational power for the rotation of the stirring shaft (13); the magnetic fluid seal (11) uses magnetic fluid to achieve dynamic sealing of the shaft, ensuring that no solid friction and gas leakage occur when the shaft rotates at high speed.

7. The device for rapid oxygen reduction by gas injection and stirring in liquid lead and bismuth according to claim 5, characterized in that: The coupling (12) is made of high temperature resistant and corrosion resistant 316L stainless steel; the stirring shaft (13) and the stirring impeller (14) are both made of 316L stainless steel, which generate strong shearing force and impact force through rotation, break up and disperse the bubbles, and promote the full mixing of the reducing gas and the lead and bismuth.

8. A device for rapid oxygen reduction by gas injection and stirring in liquid lead and bismuth according to any one of claims 6-7, characterized in that: The operation method of the liquid lead-bismuth gas injection stirring device comprises the following steps: Step S1: When the oxygen concentration in the liquid lead-bismuth alloy exceeds a threshold value, the gas injection device is started: the first solenoid valve (4) is opened to inject an inert gas into the liquid lead-bismuth; the third solenoid valve (6) is opened to ensure that excess gas is discharged through the gas outlet pipe (9); at the same time, the pressure in the tank is continuously monitored, and after the pressure reaches a balanced state, the inert gas injection is terminated and the first solenoid valve (4) is closed; Step S2: opening the second solenoid valve (5), injecting reducing gas into the lead-bismuth according to the set gas injection rate, and starting the stirring device to stir at the set stirring speed so that the reducing gas and dissolved oxygen fully react, while recording the oxygen sensor signal, and determining the optimal gas injection rate and stirring speed parameter combination under the current working condition by analyzing the oxygen concentration change rate; Step S3: When the received oxygen sensor signal is stable within the preset target value range, the stepper motor (10) and the second solenoid valve (5) are turned off to complete the entire deoxygenation operation.

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