Alkali metal non-oxidation subpackaging device and method

Abstract

The invention provides an alkali metal non-oxidation subpackaging device and method.The alkali metal non-oxidation subpackaging device comprises a heating metal tank, a glove box, a subpackaging body, a vacuumizing system and a high-purity argon supply system, the top end of the heating metal tank communicates with the glove box, and a cover plate is arranged at the communicating position; the bottom end of the heating metal tank is communicated with the split charging body, one side of the heating metal tank is communicated with a cold trap, and the cold trap is respectively communicated with the vacuumizing system and the high-purity argon supply system through a three-way valve; a gas washing bottle is arranged on a communicating pipeline of the high-purity argon supply system and the three-way valve, one side of the heating metal tank is connected with a cold trap, the cold trap is communicated with the vacuumizing system and the high-purity argon supply system with the gas washing bottle through the three-way valve, and a low-oxygen environment can be created through vacuumizing and high-purity argon replacement. The cold trap can reduce the alkali metal volatilization effect, and the gas washing bottle can remove argon impurities, so that alkali metal oxidation is effectively reduced, the subpackaging precision is improved, and the heat conduction performance of equipment such as high-temperature heat pipes is guaranteed.

Description

TECHNICAL FIELD

[0001] The application relates to the high-temperature thermal structure technical field, in particular to an alkali metal non-oxidation sub-packaging device and method. BACKGROUND

[0002] In the high-temperature thermal structure technical field, the heat-proof structure represented by the high-temperature heat pipe gradually attracts attention because the heat-proof structure can meet the demand for continuously increasing the use temperature of heat-proof materials and heat-proof structures. The high-temperature heat pipe mainly relies on alkali metal as a high-thermal-conductivity medium, and the non-oxidation sub-packaging of the alkali metal is a key factor affecting the heat-conductivity of the high-temperature heat pipe.

[0003] At present, the sub-packaging of the alkali metal is mainly realized through vacuum / high-purity argon sub-packaging technology. However, the two technologies have obvious deficiencies: under the vacuum environment, the alkali metal is easy to volatilize, which will result in low sub-packaging precision; when the impurities contained in the high-purity argon come into contact with the alkali metal, the alkali metal will be oxidized. After the alkali metal is oxidized, not only the high-thermal-conductivity of the alkali metal will be lost, but also the channel will be blocked, thereby affecting the realization of the high-thermal-conductivity function of the high-temperature heat pipe. Therefore, a non-oxidation sub-packaging device and method capable of reducing the volatilization effect of the alkali metal and improving the sub-packaging precision of the alkali metal are urgently needed. SUMMARY

[0004] The application aims to provide an alkali metal non-oxidation sub-packaging device and method, which can reduce the volatilization effect of the alkali metal and improve the sub-packaging precision of the alkali metal.

[0005] The application provides an alkali metal non-oxidation sub-packaging device, which comprises a heating metal tank, a glove box, a sub-packaging body, a vacuum pumping system and a high-purity argon supply system. The top end of the heating metal tank is communicated with the glove box, and a cover plate is arranged at the communication position. The bottom end of the heating metal tank is communicated with the sub-packaging body. A cold trap is communicated with one side of the heating metal tank. The cold trap is communicated with the vacuum pumping system and the high-purity argon supply system through a three-way valve. A gas washing bottle is arranged on the communication pipeline of the high-purity argon supply system and the three-way valve.

[0006] Further, the working medium in the gas washing bottle is potassium-sodium alloy, and the melting point of the potassium-sodium alloy is lower than 0 DEG C.

[0007] Further, the cover plate is a quartz cover plate.

[0008] Further, the background vacuum degree of the vacuum pumping system is less than 1.0*10 -3 Pa.

[0009] Further, the cold trap is a columnar or spherical stainless steel body, and the working temperature of the cold trap is 12-20 DEG C.

[0010] Further, one or more one-way exhaust holes are arranged above the glove box.

[0011] The alkali metal non-oxidation sub-packaging method is realized based on an alkali metal non-oxidation sub-packaging device, and specifically comprises the following steps: S1: opening a vacuum pumping system, controlling a three-way valve to connect the vacuum pumping system and a cold trap, vacuumizing a heating metal tank and a sub-packaging body to a specified vacuum degree, and then closing the vacuum pumping system and the three-way valve; S2: opening a high-purity argon supply system, and introducing high-purity argon into the heating metal tank and the sub-packaging body to make the pressure in the heating metal tank reach 1 atm; S3: opening a cover plate to make excess high-purity argon in the heating metal tank flow into a glove box, and gradually exhausting air in the glove box; S4: cutting a certain amount of alkali metal in the glove box, and putting the cut alkali metal into the heating metal tank; S5: closing the high-purity argon supply system and the cover plate, opening the vacuum pumping system, and controlling the three-way valve to connect the vacuum pumping system and the cold trap, and vacuumizing the heating metal tank and the sub-packaging body to the specified vacuum degree again; S6: heating the heating metal tank and the sub-packaging body to above the melting point of the alkali metal, and making the alkali metal flow into the sub-packaging body under the action of gravity after being melted.

[0012] Further, the specified vacuum degree in step S1 and step S5 ranges from 1.0 to 5.0*10 -3 Pa.

[0013] Further, the flow rate of the high-purity argon in step S2 is 200-800 ml / min.

[0014] Further, the volume of the high-purity argon flowing into the glove box in step S3 is greater than 10 times the volume of the glove box.

[0015] The technical scheme of the present application can create a low-oxygen environment through vacuumizing and high-purity argon replacement by connecting a cold trap to one side of the heating metal tank and connecting the cold trap to the vacuum pumping system and the high-purity argon supply system with a gas washing bottle through a three-way valve, the cold trap can reduce the volatilization effect of the alkali metal, and the gas washing bottle can remove argon impurities, thereby effectively reducing the oxidation of the alkali metal, improving the sub-packaging precision, and protecting the heat conduction performance of high-temperature heat pipes and other equipment. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical scheme in the specific embodiments of the present application or the prior art, the drawings needed in the following specific embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0017] Figure 1The connection structure diagram of the alkali metal oxidation-free split charging device.

[0018] Figure 2 The curve of the saturated vapor pressure of metallic sodium with temperature.

[0019] Figure 3 The temperature response curve of the sodium working medium nickel-based superalloy heat pipe obtained by split charging in a traditional process.

[0020] Figure 4 The temperature response curve of the sodium working medium nickel-based superalloy heat pipe obtained by split charging.

[0021] The figure mark explanation: 1-heating metal tank, 2-split charging body, 3-glove box, 4-cover plate, 5-vacuum extraction system, 6-high-purity argon supply system, 7-cold trap, 8-three-way valve, 9-gas washing bottle. DETAILED DESCRIPTION

[0022] The technical solutions of the present application will be described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0023] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0024] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited. In addition, the terms "mounting", "connecting", "connecting" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0025] Example 1 like Figure 1 As shown, the present invention provides an alkali metal non-oxidizing subpackaging device, comprising a heating metal tank 1, a glove box 3, a subpackaging body 2, a vacuum system 5 and a high-purity argon supply system 6. The vacuum system 5 is used to vacuum the heating metal tank 1, and comprises a molecular pump, a mechanical pump, a stop valve and a vacuum gauge. The molecular pump and the mechanical pump are connected in series with each other. When vacuuming, the mechanical pump works first. After the vacuum degree in the heating metal tank 1 is less than 10Pa, the molecular pump and the mechanical pump work simultaneously. The vacuum gauge can be installed on the heating metal tank or on a vacuum pipe close to the heating metal tank. When the vacuum gauge is installed on the heating metal tank, it should be avoided to be close to the heating element; the high-purity argon supply system 6 is used for the supply of argon, and comprises a liquid argon storage tank, a delivery pipeline, a high-pressure valve (such as a needle valve, a ball valve) and a flow meter, wherein one end of the delivery pipeline is connected to the outlet of the liquid argon storage tank, the high-pressure valve and the flow meter are sequentially installed on the delivery pipeline, the top of the heating metal tank 1 is connected to the glove box 3, and a quartz cover is provided at the connection position. The plate 4 is an independent movable plate structure used to seal the communication port between the heating metal tank 1 and the glove box 3. A sealing ring can be set at the bottom end of the quartz cover 4 to ensure the vacuum effect of the subsequent heating metal tank 1 and the sub-package 2; the bottom end of the heating metal tank 1 is connected to the sub-package 2, and the top end of the sub-package 2 is detachably sealed and connected to the bottom end of the heating metal tank 1. The two can be detachably connected by a threaded connection. One side of the heating metal tank 1 is connected to a cold trap 7. The cold trap 7 The glove box 3 is connected to the vacuum system 5 and the high-purity argon supply system 6 through a three-way valve 8. The cold trap 7 is a cylindrical or spherical stainless steel body, and the operating temperature of the cold trap 7 is 12-20°C. A washing bottle 9 is provided on the connecting pipeline between the high-purity argon supply system 6 and the three-way valve 8. The working medium in the washing bottle 9 is a potassium-sodium alloy with a melting point of -10°C. The operating temperature of the cold trap 7 is 20°C. One or more one-way exhaust holes are provided above the glove box 3, through which excess gas in the box can enter the surrounding atmosphere.

[0026] The subpackage 2 is a nickel-based high-temperature heat pipe shell. The subpackage volume of alkali metal sodium is 22g, which is close to the lower limit of 20g for nickel-based high-temperature heat pipe working fluid. The filling process parameters are as follows: the background vacuum degree of the vacuum system 5 is less than 1.0×10 -3 Pa, the purity of argon in the high-purity argon supply system 6 is 99.9999%, and the flow rate of high-purity argon is 200-800 ml / min; the leakage rate of the metal tank with heating function and the sub-packaging body 2 is 3.0×10 -9 Pa·m³ / s; the heating temperature of the heating metal can 1 and the subpackage 2 is 130°C.

[0027] Figure 2The curve of the saturated vapor pressure of metallic sodium with temperature is given, and it can be seen that when the working temperature decreases from 100 DEG C to 20 DEG C, the saturated vapor pressure of metallic sodium decreases by 4-5 orders of magnitude, that is, after the cold trap 7 is applied, the volatilization tendency of metallic sodium is greatly reduced, and the filling precision is improved.

[0028] Figure 3 and Figure 4 The temperature response curves of the nickel-based superalloy heat pipe filled with sodium working medium by the traditional process (without the gas washing bottle 9 and the cold trap 7) and the present application are given, and points 1-8 are the temperature measuring points on the high-temperature heat pipe. It can be seen that the surface temperature of the nickel-based superalloy heat pipe filled by the traditional process does not reach the uniform temperature state during the starting test, and the heat pipe fails to start; the surface temperature of the nickel-based superalloy heat pipe filled by the present application reaches the uniform temperature state during the starting test, and the heat pipe starts successfully. Further test analysis shows that the sodium alkali filled by the traditional process is obviously oxidized, and the mass of the filled metallic sodium is lower than the lower limit of the working medium filling of the heat pipe, which leads to the failure of the nickel-based superalloy heat pipe to start. On the other hand, the oxidation of the sodium alkali filled by the present application is not obvious, and the mass of the filled metallic sodium is still greater than the lower limit of the working medium filling, so the nickel-based superalloy heat pipe starts successfully. That is, compared with the traditional alkali metal filling process, the present application can more effectively reduce the oxidation effect of alkali oxidation.

[0029] The present application also provides an alkali metal non-oxidation filling method, which is realized based on an alkali metal non-oxidation filling device and specifically includes the following steps. (1) The vacuum pumping system 5 is opened, the three-way valve 8 is controlled to connect the vacuum pumping system 5 and the cold trap 7, the heating metal tank 1 and the filling body 2 are pumped to a specified vacuum degree, and then the vacuum pumping system 5 and the three-way valve 8 are closed; (2) The high-purity argon supply system 6 is opened, high-purity argon is introduced into the heating metal tank 1 and the filling body 2, and the pressure in the heating metal tank 1 reaches 1 atm; the flow rate of the high-purity argon is 200-800 ml / min; (3) The quartz cover plate 4 is opened, and the excess high-purity argon in the heating metal tank 1 flows into the glove box 3, and the air in the glove box 3 is gradually exhausted; wherein the volume of the high-purity argon flowing into the glove box 3 is greater than 10 times the volume of the glove box 3. (4) A certain amount of alkali metal is cut in the glove box 3, and the cut alkali metal is put into the heating metal tank 1; (5) The high-purity argon supply system 6 and the cover plate 4 are closed, the vacuum pumping system 5 is opened, and the three-way valve 8 is controlled to connect the vacuum pumping system 5 and the cold trap 7, and the heating metal tank 1 and the filling body 2 are pumped to a specified vacuum degree; (6) The temperature of the heating metal tank 1 and the filling body 2 is heated to 30-50 DEG C higher than the melting point of the alkali metal, and after the alkali metal is melted, it flows into the filling body 2 under the action of gravity.

[0030] wherein the vacuum degree range specified in step (1) and step (5) above is 1.0-5.0×10 -3 Pa.

[0031] Example 2 The difference between this example and Example 1 is that two-stage purification devices can also be arranged in the high-purity argon supply system, i.e. a molecular sieve adsorption tower and a deoxidizer filter can also be arranged in sequence after the gas washing bottle on the connecting pipeline between the high-purity argon supply system and the three-way valve, so as to form a double purification mode of chemical adsorption plus physical condensation to reduce the oxygen content in argon as much as possible.

[0032] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions described in the foregoing examples can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An alkali metal non-oxidation packaging device, characterized in that: It includes a heating metal can, a glove box, a packaging body, a vacuum system and a high-purity argon supply system. The top of the heating metal can is connected to the glove box, and a cover is provided at the connection position; the bottom of the heating metal can is connected to the packaging body, and one side of the heating metal can is connected to a cold trap, and the cold trap is connected to the vacuum system and the high-purity argon supply system respectively through a three-way valve; a gas washing bottle is provided on the connecting pipeline between the high-purity argon supply system and the three-way valve.

2. The alkali metal non-oxidation packaging device according to claim 1, characterized in that: The working medium in the gas washing bottle is potassium-sodium alloy, and the melting point of the potassium-sodium alloy is lower than 0°C.

3. The alkali metal non-oxidation packaging device according to claim 1, characterized in that: The cover plate is a quartz cover plate.

4. The alkali metal non-oxidation packaging device according to claim 1, characterized in that: The background vacuum degree of the vacuum system is less than 1.0×10 -3 Pa.

5. The alkali metal non-oxidation packaging device according to claim 1, characterized in that: The cold trap is a columnar or spherical stainless steel body, and the operating temperature of the cold trap is 12-20°C.

6. The alkali metal non-oxidation packaging device according to claim 1, characterized in that: One or more one-way exhaust holes are provided above the glove box.

7. A method for non-oxidative packaging of alkali metals, characterized in that: Based on the alkali metal non-oxidation packaging device according to any one of claims 1 to 6, specifically The following steps are involved: S1: Open the vacuum system, control the three-way valve to connect the vacuum system and the cold trap, evacuate the heated metal can and the subpackage to the specified vacuum degree, and then close the vacuum system and the three-way valve; S2: Open the high-purity argon gas supply system and introduce high-purity argon gas into the heating metal tank and the sub-package to make the pressure in the heating metal tank reach 1 atmosphere; S3: Open the cover to allow excess high-purity argon gas in the heated metal tank to flow into the glove box, gradually exhausting the air in the glove box; S4: cutting a certain amount of alkali metal in the glove box and placing the cut alkali metal into a heated metal can; S5: Close the high-purity argon gas supply system and the cover, open the vacuum system, and control the three-way valve to connect the vacuum system to the cold trap, and perform secondary vacuuming on the heated metal can and the subpackage to the specified vacuum degree; S6: The temperature of the heating metal can and the sub-package is heated to above the melting point of the alkali metal. After the alkali metal melts, it flows into the sub-package under the action of gravity.

8. The alkali metal non-oxidation packaging method according to claim 7, characterized in that: The vacuum range specified in step S1 and step S5 is 1.0-5.0×10 -3 Pa.

9. The alkali metal non-oxidation packaging method according to claim 7, characterized in that: The flow rate of high-purity argon in step S2 is 200-800 ml / min.

10. The alkali metal non-oxidation packaging method according to claim 7, characterized in that: In step S3 , the volume of the high-purity argon gas flowing into the glove box is greater than 10 times the volume of the glove box.

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