阅读说明：本技术 一种用于核素迁移研究的气氛控制装置 (Atmosphere control device for nuclide migration research ) 是由 周小毛 崔大庆 王玲钰 李腾 于 2021-06-22 设计创作，主要内容包括：本发明涉及一种用于核素迁移研究的气氛控制装置,属于放射性废物处理技术领域,包括玻璃瓶体,玻璃瓶体法兰上端设有密封盖,下端设有密封法兰；玻璃瓶体内盛有平衡溶液,样品台架置于玻璃瓶体内部台阶上；样品台架上端面的样品槽内放置盛有实验溶液的样品瓶,瓶内置有铂电极；导体、操作管道和进气管道分别与密封盖固接；导体通过导线与铂电极连接；进气管道下端连接下导气管,下导气管另一端浸在平衡溶液内；物料通道顶端和排气管固定在操作管道内,物料通道底端浸在实验溶液中。本发明提供的气氛控制装置,能够灵活多变适用不同工作场景,增强实验气氛纯度从而保证实验数据的真实可靠,另外材料便宜且便于获取,拆卸简单,方便放置。(The invention relates to an atmosphere control device for nuclide migration research, which belongs to the technical field of radioactive waste treatment and comprises a glass bottle body, wherein a sealing cover is arranged at the upper end of a flange of the glass bottle body, and a sealing flange is arranged at the lower end of the flange of the glass bottle body; the glass bottle body is filled with a balanced solution, and the sample rack is arranged on the step inside the glass bottle body; a sample bottle containing an experimental solution is placed in a sample groove on the upper end surface of the sample rack, and a platinum electrode is arranged in the bottle; the conductor, the operation pipeline and the air inlet pipeline are fixedly connected with the sealing cover respectively; the conductor is connected with the platinum electrode through a lead; the lower end of the air inlet pipeline is connected with a lower air duct, and the other end of the lower air duct is immersed in the balance solution; the top end of the material channel and the exhaust pipe are fixed in the operation pipeline, and the bottom end of the material channel is immersed in the experimental solution. The atmosphere control device provided by the invention can be flexibly and changeably suitable for different working scenes, enhances the purity of the experimental atmosphere so as to ensure the reality and reliability of experimental data, and is cheap and convenient to obtain materials, simple to disassemble and convenient to place.)

1. An atmosphere control device for nuclide migration research is characterized by comprising a glass bottle body (1), wherein a sealing cover (2) is arranged at the upper end of a flange of the glass bottle body (1), and a sealing flange (3) is arranged at the lower end of the flange; the bottom in the glass bottle body (1) is filled with a balance solution (12), the sample rack (10) is arranged on a step in the glass bottle body (1), and the bottom surface of the sample rack is higher than the liquid level of the balance solution (12); a plurality of sample grooves are formed in the upper end face of the sample rack (10), sample bottles (11) containing experimental solution are placed in the sample grooves, and platinum electrodes (15) are placed in the experimental solution of the sample bottles (11);

the sealing cover (2) is provided with a plurality of penetrating circular holes with different apertures, and the conductor (5), the operation pipeline (6) and the air inlet pipeline (8) are fixedly connected with the sealing cover (2) through the circular holes with corresponding apertures respectively; wherein the conductor (5) is connected with the platinum electrode (15) through a lead (16); the lower end of the air inlet pipeline (8) is connected with a lower air duct (9), and the other end of the lower air duct (9) is immersed in the equilibrium solution (12); the top end of the material channel (7) and the exhaust pipe (19) are fixed in the operation pipeline (6), and the bottom end of the material channel (7) is immersed in the experimental solution of the sample bottle (11).

2. The atmosphere control device for nuclide migration research as to claim 1, wherein the device further comprises a trace oxygen analyzer (6) for monitoring oxygen concentration and humidity inside the glass bottle body, the trace oxygen analyzer (6) comprises an oxygen probe (14) arranged above the sample rack (7) inside the glass bottle body (1) and a display arranged outside the glass bottle body (1), and a connecting line between the oxygen probe (14) and the display passes through a corresponding circular hole of the sealing cover (2) and is cured and sealed by vacuum sealing mud and epoxy resin; the oxygen probe (14) is a photoluminescent detector with low sensitivity to humidity.

3. The atmosphere control device for nuclide migration study as to claim 1, characterized in that the body of the glass bottle body (1) is in the shape of a stepped cylinder, the lower half has a slightly smaller inner diameter than the upper half, and the upper edge has a ground flange.

4. The atmosphere control device for nuclide migration research as to claim 3, wherein the sealing cover (2) is made of stainless steel, is circular in shape, has a diameter slightly larger than the outer diameter of the glass bottle body flange, and is uniformly distributed with a plurality of through holes along the outer circumference; a first sealing ring (4) made of silica gel is arranged between the contact surface of the sealing cover (2) and the glass bottle body (1); the bottom of the sealing cover (2) is coated with anticorrosive paint.

5. The atmosphere control device for nuclide migration research as to claim 3 or 4, wherein the sealing flange (3) is made of stainless steel and shaped like a circular ring, a second sealing ring (22) made of silica gel is arranged between the sealing flange (3) and the flange of the glass bottle body (1), and a plurality of through holes corresponding to the through holes on the sealing cover (2) are uniformly distributed along the outer circumference.

6. The atmosphere control device for nuclide migration research as to claim 1, wherein the conductor (5) is made of copper, penetrates through and is fixed in a corresponding round hole on the sealing cover (2), a silica gel gasket is arranged between the contact surfaces of the conductor (5) and the sealing cover (2), and the top end of the contact surface of the conductor and the sealing cover (2) is sealed by epoxy resin; the platinum electrode (15) is made of platinum and is in the shape of a platinum sheet or a platinum net, the upper end of the platinum electrode is a rod-shaped polytetrafluoroethylene rod with a built-in lead, and the platinum electrode penetrates out of the bottle cap of the sample bottle (11); the conductor (5), the platinum electrode (15), the lead (16), the experimental solution in the sample bottle (11), the salt bridge in the material channel (7), the additional electrochemical workstation, the saturated potassium chloride solution and the reference electrode form a loop for monitoring the change of the Eh value of the experimental solution.

7. The atmosphere control device for nuclide migration research as to claim 6, wherein the operating pipe (6) is made of stainless steel, is welded to the sealing cover (2), and is internally inserted with a plurality of material channels (7) and an exhaust pipe (19), an opening at the upper end of the exhaust pipe (19) is slightly higher than the top end of the material channels (7), and the upper ends of the exhaust pipe (19) and the material channels (7) are fixed and sealed by vacuum sealing mud (17) and epoxy resin (18); the material channel (7) is made of PVC, and a small opening for convection with gas in the glass bottle body (1) is formed in the middle of the material channel at a set distance; the lower end of the material channel (7) is fixed in the sample bottle (11) through a plastic cutting sleeve at the upper end and the lower end of the bottle cap of the sample bottle (11).

8. The atmosphere control device for nuclide migration research as to claim 7, wherein the air inlet pipe (8) is made of stainless steel, is connected with the sealing cover (2) by welding, and has an upper end connected with an upper air duct, the upper air duct is connected with an external experimental air cylinder, the lower end of the air inlet pipe (8) is connected with a lower air duct (9), and the lower air duct (9) passes through a through hole on the sample rack (10) and is connected into the equilibrium solution (12); the outer side of the upper end of the air inlet pipeline (8) is provided with a preformed thread and is matched with a screw cap (21) for use.

9. The atmosphere control device for nuclide migration study as to claim 1, wherein the sample rack (10) is made of polytetrafluoroethylene, is shaped like a circular truncated cone, and has an outer diameter matched with the inner diameter of the upper half part of the glass bottle body (1); the upper end of the sample rack (10) is prefabricated with a plurality of sample grooves for fixing the sample bottles (11).

10. An atmosphere control device for nuclide migration study as defined in any of claims 1 or 6-9, characterized in that the composition of the equilibration solution (12) is determined based on the experimental atmosphere and the experimental solution in the sample vial, the equilibration solution (12) having a total ion concentration comparable to the experimental solution in the sample vial (11).

Technical Field

The invention belongs to the technical field of radioactive waste disposal, and particularly relates to an atmosphere control device for nuclide migration research.

Background

Deep geological disposal is the most viable long-term management solution specifically for high-level radioactive waste. The radioactive waste is buried in a stable rock stratum of 500-1000 meters underground to build a disposal warehouse, and the multiple barriers formed by natural environment and artificial facilities can effectively prevent the radioactivity from diffusing to human life circle for a long time (ten thousand years or even longer). The development of the radioactive waste disposal library in the early stage needs a large amount of verification experiments, wherein the verification experiments comprise research and simulation of nuclide migration behavior and corrosion resistance behavior of packaging materials in the disposal library environment with the atmosphere condition as the core. The research is mainly to obtain the concentration and form change data of related nuclides, phase composition data of corrosion products and sediments and moment change data of Eh value of solution through leaching experiments. The data acquisition requires stable atmosphere maintenance, while some valence-variable nuclides are very sensitive to oxygen in the experimental process, and the residual oxygen easily misleads the real experimental data.

The current routine way to maintain atmospheric conditions in the laboratory is to use a hypoxic glove box. Inert gas is filled into a closed box body, and gases such as water, oxygen and the like are removed by an automatic gas purification system with a renewable molecular sieve, a copper catalyst and the like, so that a long-term stable atmosphere condition is obtained. However, the following problems exist for simulating the environment under deep geological disposal conditions:

1. the low-oxygen glove box is a circulating system, the component proportion of multi-component gas is difficult to keep constant after multiple cycles, for example, carbon dioxide is easily absorbed by leachate, hydrogen is easily consumed by metal parts, and long-term hydrogen existence can cause hydrogen brittleness of steel parts. Still other deep geologic modeling scenarios require a certain proportion of oxygen to be present, which is clearly contrary to the concept of a hypoxic glove box.

2. The deep geological treatment simulation scene mainly considers the influence of nuclides in a solution system, and related gases need to have stable water vapor equilibrium partial pressure. Hypoxic glove boxes have difficulty maintaining significant water vapor presence because oxygen probes are particularly sensitive to water molecules. In addition, the leaching experiment requires a series of liquid-related operating steps, which are detrimental to the work of the glove box. If put liquid into the container of screwing, reduce the operation of uncapping step by step, this again hardly realizes the atmosphere balance outside and the bottle in the bottle, influences the accuracy of experiment.

3. In addition, hypoxic glove boxes are expensive, require specialist maintenance, and are expensive to maintain, while most leaching experiments require longer periods, even years, and it is clear that hypoxic glove boxes are not the best choice.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention aims to provide an atmosphere control device for nuclide migration research, which can adapt to experiments of various atmosphere conditions, provide specific component gases and long-term constant conditions, and meet the requirement of sampling and monitoring the change of the Eh value of a system at any time, thereby ensuring that relatively comprehensive, real and reliable experimental data are obtained.

In order to achieve the above purposes, the invention adopts a technical scheme that:

an atmosphere control device for nuclide migration research comprises a glass bottle body, wherein a sealing cover is arranged at the upper end of a flange of the glass bottle body, and a sealing flange is arranged at the lower end of the flange; the bottom of the glass bottle body is filled with a balance solution, the sample rack is arranged on a step in the glass bottle body, and the bottom surface of the sample rack is higher than the liquid level of the balance solution; a plurality of sample grooves are formed in the upper end face of the sample rack, sample bottles containing experimental solution are placed in the sample grooves, and platinum electrodes are placed in the experimental solution of the sample bottles;

the sealing cover is provided with a plurality of penetrating circular holes with different apertures, and the conductor, the operation pipeline and the air inlet pipeline are fixedly connected with the sealing cover through the circular holes with corresponding apertures respectively; wherein the conductor is connected with the platinum electrode through a lead wire; the lower end of the air inlet pipeline is connected with a lower air duct, and the other end of the lower air duct is immersed in the balance solution; the top end of the material channel and the exhaust pipe are fixed in the operation pipeline, and the bottom end of the material channel is immersed in the experimental solution of the sample bottle.

Further, the atmosphere control device for nuclide migration research further comprises a trace oxygen analyzer for monitoring oxygen concentration and humidity inside the glass bottle body, wherein the trace oxygen analyzer comprises an oxygen probe arranged above the sample rack in the glass bottle body and a display arranged outside the glass bottle body, and connecting lines of the oxygen probe and the display penetrate through corresponding round holes of the sealing cover and are cured and sealed by vacuum sealing mud and epoxy resin; the oxygen probe is a photoluminescence detector with low sensitivity to humidity.

Further, as for the atmosphere control device for nuclide migration research, the body of the glass bottle body is in a cylindrical shape with steps, the inner diameter of the lower half part is slightly smaller than that of the upper half part, and the upper edge of the glass bottle body is provided with a ground flange.

Further, according to the atmosphere control device for nuclide migration research, the sealing cover is made of stainless steel and is circular, the diameter of the sealing cover is slightly larger than the outer diameter of the glass bottle body flange, and a plurality of through holes are uniformly distributed along the outer circumference; a first sealing ring made of silica gel is arranged between the contact surface of the sealing cover and the glass bottle body; the bottom of the sealing cover is coated with anticorrosive paint.

Further, as above, in the atmosphere control device for nuclide migration research, the sealing flange is made of stainless steel and shaped like a circular ring, a second sealing ring made of silica gel is arranged between the sealing flange and the glass bottle body flange, and a plurality of through holes corresponding to the through holes in the sealing cover are uniformly distributed along the outer circumference.

Further, according to the atmosphere control device for nuclide migration research, the conductor is made of copper and penetrates through and is fixed in the corresponding round hole in the sealing cover, a silica gel gasket is arranged between the contact surface of the conductor and the sealing cover, and the top end of the contact surface of the conductor and the sealing cover is sealed by epoxy resin; the platinum electrode is made of platinum and is in the shape of a platinum sheet or a platinum net, and the upper end of the platinum electrode is provided with a rod-shaped polytetrafluoroethylene rod with a built-in lead and penetrates out of the bottle cap of the sample bottle; the conductor, the platinum electrode, the lead, the experimental solution in the sample bottle, the salt bridge in the material channel, the additional electrochemical workstation, the saturated potassium chloride solution and the reference electrode form a loop for monitoring the Eh value change of the experimental solution.

Further, according to the atmosphere control device for nuclide migration research, the operation pipeline is made of stainless steel and is welded with the sealing cover, the material channels and the exhaust pipe are inserted into the operation pipeline, the upper end opening of the exhaust pipe is slightly higher than the top end of the material channels, and the exhaust pipe and the upper end of the material channels are fixed and sealed through vacuum sealing mud and epoxy resin; the material channel is made of PVC, and a small opening for convection with gas in the glass bottle body is formed in the middle of the material channel at a set distance; the lower end of the material channel is fixed in the sample bottle through the plastic clamping sleeve at the upper end and the lower end of the sample bottle cap.

Further, according to the atmosphere control device for nuclide migration research, the air inlet pipeline is made of stainless steel and is connected with the sealing cover in a welding mode, the upper end of the air inlet pipeline is connected with the upper air duct, the upper air duct is connected with the external experimental air cylinder, the lower end of the air inlet pipeline is connected with the lower air duct, and the lower air duct penetrates through the through hole in the sample rack and is connected into the equilibrium solution; and the outer side of the upper end of the air inlet pipeline is provided with a prefabricated thread and is matched with a screw cap for use.

Further, according to the atmosphere control device for nuclide migration research, the sample rack is made of polytetrafluoroethylene and is in the shape of a circular truncated cone, and the outer diameter of the sample rack is matched with the inner diameter of the upper half part of the glass bottle body; the upper end of the sample rack is prefabricated with a plurality of sample grooves for fixing the sample bottles.

Further, the atmosphere control apparatus for nuclide migration study as described above determines the composition of the equilibrium solution based on the experimental atmosphere and the experimental solution in the sample bottle, the total ion concentration of the equilibrium solution being equivalent to the experimental solution in the sample bottle.

The atmosphere control device has the following remarkable technical effects:

1. the method is suitable for long-time leaching experiments with normal temperature, normal pressure, dust-free and variable gas components in a scene, and can timely monitor the Eh value and the nuclide concentration change of a sample system or assist an electrolytic cell to research the electrochemical properties related to nuclide migration under the gas with a specific component;

2. the gas with specific components can be provided, and the long-term constant conditions can be provided, so that relatively comprehensive, real and reliable experimental data can be obtained;

3. the material is cheap and convenient to obtain, and the dismantlement is simple, conveniently places.

Drawings

FIG. 1 is a schematic structural diagram of an atmosphere control apparatus for nuclide migration studies provided in an embodiment of the present invention;

FIG. 2 is a schematic view of the sealing cap of the embodiment of FIG. 1;

FIG. 3 is a schematic structural view of the sealing flange in the embodiment of FIG. 1;

FIG. 4 is a schematic view of the internal structure of the operation pipeline in the embodiment of FIG. 1;

FIG. 5 is a schematic diagram of the connection to an external device in operation of the embodiment of FIG. 1;

FIG. 6 is a schematic diagram of another embodiment of the present invention in operation in connection with an external device;

FIG. 7 is a schematic diagram of the connection of a further embodiment of the present invention to an external device in operation;

wherein, 1-a glass bottle body; 2-sealing cover; 3-sealing the flange; 4-a first sealing ring; 5-a conductor; 6-operating the pipeline; 7-a material channel; 8-an air inlet duct; 9-lower airway; 10-a sample stage; 11-sample vial; 12-equilibrium solution; 13-trace oxygen analyzer; 14-an oxygen probe; 15-a platinum electrode; 16-a wire; 17-vacuum sealing mud; 18-epoxy resin; 19-an exhaust pipe; 20-bolt and nut; 21-a screw cap; 22-second sealing ring.

Detailed Description

The invention is further described with reference to specific embodiments and drawings attached to the description.

Referring to fig. 1-4, the device mainly comprises a glass bottle body 1, a sealing cover 2 is arranged at the upper end of a flange of the glass bottle body 1, a sealing flange 3 is arranged at the lower end of the flange, a balanced solution 12 is contained at the bottom of the glass bottle body 1, a sample rack 10 is arranged on a step in the glass bottle body 1, and the bottom surface of the sample rack is higher than the liquid level of the balanced solution 12; a plurality of sample grooves are formed in the upper end face of the sample rack 10, sample bottles 11 containing experimental solution are placed in the sample grooves, and platinum electrodes 15 are placed in the experimental solution of the sample bottles 11;

the sealing cover 2 is provided with a plurality of penetrating circular holes with different apertures, and the conductor 5, the operation pipeline 6 and the air inlet pipeline 8 are fixedly connected with the sealing cover 2 through the circular holes with corresponding apertures respectively; wherein the conductor 5 is connected with the platinum electrode 15 through a lead 16; the lower end of the air inlet pipeline 8 is connected with a lower air duct 9, and the other end of the lower air duct 9 is immersed in the balance solution 12; the top end of the material channel 7 and the exhaust pipe 19 are fixed in the operation pipeline 6, and the bottom end of the material channel 7 is immersed in the experimental solution of the sample bottle 11;

the device also comprises a trace oxygen analyzer 6 for monitoring the oxygen concentration and humidity inside the glass bottle body. The trace oxygen analyzer 6 consists of an oxygen probe 14 and a display, the oxygen probe 14 is arranged above the sample rack 7 in the glass bottle body 1, the display is arranged outside the glass bottle body 1, and a connecting wire of the oxygen probe 14 and the display penetrates through a corresponding round hole of the sealing cover 2.

The main body of the glass bottle body 1 is in a cylindrical shape with steps, the inner diameter of the lower half part is slightly smaller than the upper half part, and the upper edge is provided with a ground flange. This structure can realize upper and lower interlayer, and sample rack 7 is placed on upper portion, and the bottom holds balanced solution.

The sealing cover 2 is made of stainless steel, is round in shape, has a diameter slightly larger than the outer diameter of the glass bottle body flange, is provided with an O-shaped ring with the size corresponding to that of the glass bottle body flange on the contact surface with the glass bottle body 1 and is slightly lower than the whole, and is internally provided with a first sealing ring 4 which is made of silica gel; a plurality of through holes are uniformly distributed on the periphery of the sealing cover 2 slightly outside the periphery of the glass bottle body flange and used for inserting bolts; in order to prevent the steel from rusting and polluting the container, the bottom of the sealing cover 2 is also coated with a layer of anticorrosive paint.

The lower end face of the glass bottle body flange is provided with a sealing flange 3 which is made of stainless steel and is in a circular ring shape, the inner side of the sealing flange is slightly lower than the outer side of the sealing flange, and the diameter of the inner side of the sealing flange corresponds to the lower end of the glass bottle body flange. A second sealing ring 22 is arranged between the sealing flange 3 and the glass bottle body flange, the material is silica gel, and a plurality of through holes corresponding to the through holes in the sealing cover 2 are uniformly distributed on the periphery of the outer side of the sealing flange 3. The sealing cover 2, the sealing flange 3, the first sealing ring 4, the second sealing ring 22 and the bolt and nut 20 cooperate to realize the integral sealing of the device.

The conductor 5 is made of copper and penetrates through and is fixed in a corresponding round hole in the sealing cover 2, a silica gel gasket is arranged between the contact surface of the conductor 5 and the sealing cover 2, and the top end of the contact surface of the conductor 5 and the sealing cover 2 is sealed by epoxy resin, so that sealing and insulation are realized;

the platinum electrode 15 is made of platinum and is in the shape of a platinum sheet or a platinum net, the upper end of the platinum electrode is a rod-shaped polytetrafluoroethylene rod with a built-in lead, and the rod-shaped polytetrafluoroethylene rod penetrates out of the bottle cap of the sample bottle 11; the lead 16 is a common soft lead, the periphery is an insulator, the upper end of the lead is connected with the conductor 5, and the lower end of the lead is connected with the lead on the platinum electrode 15.

The conductor 5, the platinum electrode 15, the lead 16, the experimental solution in the sample bottle 11, the salt bridge in the material channel 7, the additional electrochemical workstation, the saturated potassium chloride solution and the reference electrode form a loop for monitoring the Eh value change of the experimental solution.

The operation pipeline 6 is made of stainless steel, is connected with the sealing cover 2 in a welding mode, has the inner diameter of about 2cm, and is internally inserted with a plurality of material channels 7 and an exhaust pipe 19. The exhaust pipe 19 and the upper end of the material channel 7 are fixed by vacuum sealing mud 17, and then a layer of epoxy resin 18 is poured to realize sealing; the upper end opening of the exposed exhaust pipe 19 is slightly higher than the top end of the material channel 7, so that air is prevented from being introduced into the material channel 7 during operation.

The material channel 7 is used for conveying the sampler and the salt bridge, is made of PVC and has the size ofThe top end of the material channel 7 is arranged at the inner side of the operation pipeline 6, the bottom end of the material channel is inserted into the experimental solution of the sample bottle 11, and a small opening is formed in the middle of the material channel 7 at a certain distance and used for convection with the gas in the glass bottle body; the upper end and the lower end of the bottle cap of the sample bottle 11 are provided with plastic clamping sleeves, and the material channel 7 and the upper end and the lower end of the bottle cap of the sample bottle 11 are fixed by the plastic clamping sleeves to prevent movement.

The material of admission line 8 is stainless steel, adopts welded connection with sealed lid 2, and upper end connects the air duct, goes up the air duct and is used for meeting with the gas cylinder for the experiment, and its lower extreme connects down air duct 9, and lower air duct 9 passes the pipe perforation on sample rack 10 and inserts in balanced solution 12, and lower air duct 9 opening will be less than the liquid level of balanced solution 12. The outer side of the upper end of the air inlet pipeline 8 is pre-threaded and is matched with a screw cap 21 for use.

The sample rack 10 is made of polytetrafluoroethylene, is shaped like a circular truncated cone, and has an outer diameter matched with the inner diameter of the upper half part of the glass bottle body 1, so that the sample rack can be just and stably placed on the step of the upper half part of the glass bottle body 1 without being required to be tightly matched with the glass bottle body 1. A plurality of sample grooves with certain depth are prefabricated at the upper end of the sample bottle, the inner diameter of the sample grooves is slightly larger than the outer diameter of the sample bottle 11, and the sample bottles 11 are fixed. A through hole with the aperture slightly larger than the outer diameter of the lower air duct 9 is arranged beside the sample groove and is used for guiding the lower air duct 9 to enter the equilibrium solution 12.

The composition of the equilibration solution 12 depends on the experimental atmosphere and the experimental solution in the sample bottle, and its total ion concentration is comparable to the experimental solution in the sample bottle 11. The device has the functions of maintaining the balance of gas components and humidity in the glass bottle body 1 and preventing experimental errors caused by the fact that the liquid level of the sample bottle 11 is increased or reduced due to excessive evaporation or water absorption of experimental solution caused by great difference with the water vapor pressure of the experimental solution in the sample bottle 11. If the gas containing carbon dioxide is used for experiments, the equilibrium solution can be added with corresponding amount of calcium carbonate and sodium carbonate; the experiment requires low oxygen atmosphere, and the corresponding amount of ferrous chloride and reducing iron powder can be added into the equilibrium solution.

The oxygen probe 14 of the trace oxygen analyzer 13 is a photoluminescent detector with low sensitivity to humidity, such as a photoluminescent oxygen detector with cross sensitivity to humidity reduction (application patent No. CN 20110366889); the display is a common touch screen display, and the power supply can be switched on at any time to read the internal oxygen concentration and humidity. When the connecting line of the oxygen probe 14 and the display passes through the round hole of the sealing cover 2, the curing and sealing are realized by adopting the vacuum mud sealing at the bottom and the epoxy resin at the upper part. Only when the experiment requires low oxygen content to the atmosphere or is a certain constant value, the trace oxygen analyzer is used for monitoring data, other experiments do not need, and an oxygen content alarm threshold value is not set.

When the atmosphere control device for nuclide migration research provided by the embodiment of the invention is used specifically, other equipment components need to be combined, and a use method of the device provided by the invention is described below with reference to fig. 5. The basic operation process is as follows:

s1, fixing one end of each material channel 7 and the exhaust pipe 19 in the operation pipeline 6 by using vacuum sealing mud 17, wherein the upper ends of all the pipelines are lower than the opening height of the upper end of the operation pipeline 6, pouring by using prepared epoxy resin 18, and horizontally placing the sealing cover 2 during pouring to wait for 24 hours for curing.

S2, placing the platinum electrode 15 and the lower end of the material channel 7 into the sample bottle 11, connecting the platinum electrode 15 with the lead 16, and connecting the lead 16 with the conductor 5, wherein the inner side and the outer side which are in contact with the bottle cap of the sample bottle 11 are fixed by plastic cutting sleeves, which is beneficial to keeping the positions of the platinum electrode 15 and the material channel 7 in the sample bottle 11 unchanged for a long time.

S3, preparing a balance solution 12 at the bottom according to the experimental atmosphere and the experimental solution, if a reagent sensitive to air such as ferrous chloride is put in the balance solution, the reagent is not put in the balance solution urgently, and the balance solution is introduced from the air inlet pipeline 8 after being covered, sealed and exhausted for a period of time; if the low-oxygen atmosphere is needed, reducing iron powder is added in advance at the bottom, or the reducing iron powder and ferrous chloride are added simultaneously from the air inlet pipeline 8.

And S4, connecting the air inlet pipeline 8 with the experimental air bottle to start air inlet.

S5, adding the prepared solid sample into the sample bottle 11, pouring the prepared experimental solution, and blowing the experimental solution for half an hour by using the target gas if exhausting is needed.

S6, placing the first sealing ring 4, the second sealing ring 22, the sealing cover 2 and the sealing flange 3 above and below the flange of the glass bottle body 1 in sequence, and screwing and fixing the two sealing rings in sequence by using the diagonal of the bolt and the nut 20, wherein the nut 21 is not added.

S7, if the internal oxygen concentration needs to be monitored, the oxygen analyzer 13 is opened for monitoring until the oxygen content reaches the expected and stable value, and then the gas is cut off and the screw cap 21 is screwed.

And S8, sampling. Unscrewing a screw cap 21, continuously introducing experimental gas, introducing a plastic pipe with the outer diameter less than 4mm from a port of a material channel 7 at the upper end of an operation pipeline 6, introducing the plastic pipe into an experimental solution, and sampling by adopting a matched sampler; after sampling, the screw cap 21 is quickly screwed and the gas is cut off.

S9, Eh value measurement. Unscrewing a screw cap 21, continuously introducing experimental gas, introducing a plastic pipe with the outer diameter smaller than 4mm from a port of a material channel 7 at the upper end of an operation pipeline 6, filling agar of saturated potassium chloride prepared in advance into the plastic pipe to serve as a salt bridge, putting the upper end of the plastic pipe into 1mol/L potassium chloride solution, simultaneously putting a reference electrode into the potassium chloride solution, and forming a loop together with an electrochemical workstation, a conductor 5 and a lead 16 to monitor the Eh value of the experimental solution.

And S10, placing. When the gas is placed for a long-term experiment, working gas is periodically introduced and exhausted, and the internal gas components are kept constant. In addition, the device is far from the irradiation of sunlight and the abnormal heat source, so as to prevent the transportation.

The use and usage of the present invention will be further described with reference to fig. 6 and 7.

The first application is as follows: research on reductive deposition behavior of iron-based material to nuclide

A large amount of reducing iron-based materials are used between a packaging container used in deep geological processing engineering of high-level radioactive wastes and spent fuel, have reducing deposition effect on dissolved nuclide and can prevent the nuclide from migrating. The experimental atmosphere is 0.03% CO2-Ar, the solid is iron sheet with a certain surface area, the nuclide is various forms of high-valence uranium (UO22+) and high-valence selenium (SeO32+ and SeO42+), the experimental solution in the sample bottle is 10mM sodium chloride +2mM sodium bicarbonate, and the equilibrium solution at the bottom of the device is 10mM ferrous chloride + saturated calcium carbonate + excessive reducing iron powder. The oxygen solubility is strictly controlled to be lower than 1ppm during the experiment process, because the high valence nuclide reduced by iron is likely to be oxidized again. In addition, the rust formed by the oxygen-free corrosion of iron is easily destroyed by oxygen, which affects the subsequent surface analysis. Periodic sampling to analyze the nuclide concentration and monitoring of the solution Eh helps to study the mechanism of the process. The experimental procedure was the same as the basic procedure described above.

The second purpose is as follows: study on oxygen consumption of copper material of packaging container

Cast copper is used as a packaging container in deep geological disposal engineering of high-level wastes, so that the structural strength requirement is met, peripheral residual oxygen is continuously consumed to avoid premature exposure of spent fuel, and the disposal safety is maintained. The method comprises the following steps of doping 0.03% CO2-Ar with different oxygen concentrations in a gas atmosphere, wherein the solid is a copper sheet with a certain surface area, the experimental solution is 10mM of sodium chloride and 2mM of sodium bicarbonate, and the equilibrium solution at the bottom of the device is 10mM of sodium chloride and saturated calcium carbonate. And (3) carrying out long-time gas washing at the beginning of the experiment to stably maintain the oxygen concentration at an expected level, then monitoring the change of the oxygen concentration in time, and analyzing the thickness of the corrosion layer of the copper sheet after the experiment is finished. The experimental procedure is the same as the basic operation procedure, the experimental device is shown in fig. 6, and the Eh value change does not need to be monitored in the experiment, so that some parts can be removed.

The application is three: electrochemical study for simulating corrosion dissolution of spent fuel (lobe element doped uranium dioxide)

The main body of the spent fuel is uranium dioxide, the dissolving behavior of the uranium dioxide seriously influences the migration behavior of most radionuclides in the spent fuel, and the research on the electrochemical behavior of the uranium dioxide in different environments helps us to understand the mechanism and the process of oxidative dissolution. The working electrode is simulated spent fuel or uranium dioxide, the experimental solution is 10mM sodium chloride, sodium bicarbonate with different concentrations, ferric chloride with different concentrations, hydrogen peroxide with different concentrations, calcium chloride with different concentrations and the like, and the atmosphere is Ar, 0.03% CO2-Ar, 4% H2-0.03% CO2-Ar and the like. The experimental steps are the same as the basic operation process, and the experimental device is shown in fig. 7, and can effectively remove the interference of air on the experiment.

The atmosphere control device for nuclide migration research provided by the invention is used for simulating the atmosphere of nuclide migration in a deep geological disposal environment, can adapt to experiments of various atmosphere conditions, provides specific component gas and long-term constant conditions, and has good air tightness, and the leakage rate is less than or equal to 0.05 vol%/h; meanwhile, the requirement of sampling and monitoring the change of the Eh value of the system at any time is met, so that relatively comprehensive, real and reliable experimental data are ensured to be obtained; in addition, the utilization rate is high, and therefore the experiment cost is reduced.

The above-described embodiments are merely illustrative of the present invention, which may be embodied in other specific forms or in other specific forms without departing from the spirit or essential characteristics thereof. The described embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. The scope of the invention should be indicated by the appended claims, and any changes that are equivalent to the intent and scope of the claims should be construed to be included therein.