Molten salt electrolyte primary crystal temperature measuring device

Abstract

A molten salt electrolyte primary crystal temperature measuring device belongs to the technical field of molten salt electrolyte physical property testing, and comprises a high temperature furnace, a crucible, a sealing cover, a support, a conductance cell, a thermocouple, a resistance measuring instrument, a temperature measuring instrument and a computer, and the conductance cell adopts a duplex integrated structure or a single-tube split structure. According to the molten salt electrolyte primary crystal temperature measuring device, the conductance cell is used for measuring the resistance of the molten salt electrolyte, a curve of the melt resistance changing along with the temperature is drawn, when non-conductive crystals are separated out from the surface of the electrode of the conductance cell, inflection points appear on the curve of the melt resistance changing along with the temperature, and the molten salt electrolyte primary crystal temperature is measured. The temperature corresponding to the inflection point is the primary crystal temperature of the molten salt electrolyte; and meanwhile, a thermocouple is used for synchronously measuring the melt temperature of the molten salt electrolyte, a melt step cooling curve is drawn, and through mutual verification of the melt step cooling curve and a curve of melt resistance changing along with the temperature, the identification reliability of the molten salt electrolyte primary crystal temperature is further improved.

Description

Technical Field

[0001] This utility model belongs to the field of molten salt electrolyte physical property testing technology, and in particular relates to a device for measuring the primary crystallization temperature of molten salt electrolyte. Background Technology

[0002] The primary crystallization temperature of a molten salt electrolyte refers to the temperature at which crystals first appear during the process of a molten salt transforming from a fully molten state to a solid state through slow cooling. The primary crystallization temperature is a crucial fundamental property of molten salt electrolytes because understanding its primary crystallization temperature is essential before studying other molten salt properties. In industrial electrolysis, the electrolysis temperature is determined based on the primary crystallization temperature of the molten salt. Furthermore, in the field of molten salt thermal energy storage, the primary crystallization temperature directly affects the lower operating limit of the storage system; below this temperature, the molten salt loses its fluidity. Therefore, accurately measuring the primary crystallization temperature of molten salt electrolytes is of paramount importance.

[0003] Currently, the primary crystallization temperature of molten salt electrolytes can be measured using various methods, including the gradual cooling curve method and differential thermal analysis. These methods utilize the exothermic property of molten salt electrolytes during crystallization. Taking the gradual cooling curve method as an example, when measuring the primary crystallization temperature of molten salt electrolytes, the molten salt electrolyte is first completely melted. Then, a thermocouple with its hot end exposed is directly inserted into the melt. The melt is then slowly cooled, and a gradual cooling curve is plotted. When crystals precipitate at the hot end of the thermocouple, the exothermic crystallization will cause an inflection point on the gradual cooling curve. The temperature corresponding to the inflection point is the primary crystallization temperature of the molten salt electrolyte.

[0004] However, the step cooling curve method is only applicable to simple molten salt systems because the step cooling curves of simple molten salt systems have relatively clear inflection points that are easier to identify. But as research has progressed, the composition of molten salt electrolytes has become increasingly complex, making it difficult to find clear inflection points on the step cooling curves of complex molten salt systems. Therefore, the traditional step cooling curve method can no longer meet the needs of scientific research and industrial production of complex molten salt systems.

[0005] Chinese patent application CN116297673A discloses a method for detecting and analyzing the primary crystallization temperature of an electrolyte. This method determines the primary crystallization temperature of the electrolyte by utilizing the difference in conductivity of the electrolyte melt as a function of temperature when the electrolyte melt is turbid below the primary crystallization temperature and clear above the primary crystallization temperature. However, the conductivity measurement method used in this method is the CVCC method, which is a discontinuous method for measuring the conductivity of molten salts. The CVCC method requires moving the electrode for each conductivity measurement, and this method requires measuring the conductivity values ​​at 11 temperature points without continuously plotting the conductivity curve. Therefore, using this method to measure the primary crystallization temperature of molten salt electrolytes is not only complex in operation but also cumbersome in subsequent data analysis. Utility Model Content

[0006] To address the problems existing in the prior art, this utility model provides a device for measuring the primary crystallization temperature of molten salt electrolyte. It utilizes a conductivity cell to measure the resistance of the molten salt electrolyte and plots a curve showing the change in melt resistance with temperature. When non-conductive crystals precipitate on the electrode surface of the conductivity cell, an inflection point appears on the curve of melt resistance versus temperature. The temperature corresponding to this inflection point is the primary crystallization temperature of the molten salt electrolyte. Simultaneously, a thermocouple is used to measure the melt temperature of the molten salt electrolyte and plot a melt cooling curve. By cross-referencing the melt cooling curve with the melt resistance versus temperature curve, the reliability of identifying the primary crystallization temperature of the molten salt electrolyte is further improved.

[0007] To achieve the above objectives, this utility model adopts the following technical solution: a molten salt electrolyte primary crystallization temperature measuring device, comprising a high-temperature furnace, a crucible, a cover, a support, a conductivity cell, a thermocouple, a resistance measuring instrument, a temperature measuring instrument, and a computer; the crucible is placed inside the high-temperature furnace and is used to hold the molten salt electrolyte; the cover is fastened to the open end of the crucible; the support is fixedly installed above the high-temperature furnace; the conductivity cell and thermocouple are vertically mounted on the support, with their lower ends passing through the cover and inserted into the molten salt electrolyte; the upper end of the conductivity cell is electrically connected to the resistance measuring instrument via a wire, and the resistance measuring instrument is electrically connected to the computer; the upper end of the thermocouple is electrically connected to the temperature measuring instrument via a wire, and the temperature measuring instrument is electrically connected to the computer.

[0008] The conductivity cell adopts a dual-unit integrated structure or a single-tube split structure.

[0009] When the conductivity cell adopts a dual-unit integrated structure, it includes a first electrode rod, a second electrode rod, a dual-through-hole electrode protection tube, and a dual-through-hole capillary tube; the dual-through-hole electrode protection tube is vertically fixed on a support, and the thermocouple is distributed side by side with the dual-through-hole electrode protection tube; the first electrode rod and the second electrode rod are respectively fixedly inserted into the two through holes of the dual-through-hole electrode protection tube, and the first electrode rod, the second electrode rod, and the dual-through-hole electrode protection tube are an integrated prefabricated assembly, and the top ends of the first electrode rod and the second electrode rod are connected to a resistance measuring instrument through wires; the dual-through-hole capillary tube is vertically fixed on a cap, and the lower end of the tube body is inserted into molten salt electrolyte, the dual-through-hole capillary tube is located directly below the dual-through-hole electrode protection tube, and the two are coaxially distributed; the first electrode rod and the second electrode rod respectively pass through the two through holes of the dual-through-hole capillary tube, and the lower ends of the first electrode rod and the second electrode rod are inserted into molten salt electrolyte.

[0010] When the conductivity cell adopts a dual-unit integrated structure, the cover is provided with thermocouple perforation and double-through-hole capillary perforation respectively; the thermocouple is fitted into the thermocouple perforation; the double-through-hole electrode protection tube is fitted into the double-through-hole capillary perforation and fixedly fitted.

[0011] When the conductivity cell adopts a single-tube split structure, it includes a first electrode rod, a second electrode rod, a first single-hole electrode protection tube, a second single-hole electrode protection tube, a first single-hole capillary tube, and a second single-hole capillary tube; both the first and second single-hole electrode protection tubes are vertically fixed on a support; the thermocouple is located between the first and second single-hole electrode protection tubes; the first electrode rod is fixedly inserted into the first single-hole electrode protection tube, and the first electrode rod and the first single-hole electrode protection tube are an integral prefabricated assembly; the top of the first electrode rod is connected to a resistance measuring instrument via a wire; the second electrode rod is fixedly inserted into the second single-hole electrode protection tube, and the second electrode rod and the second single-hole capillary tube are... The single-hole electrode protection tube is an integral prefabricated assembly. The top of the second electrode rod is connected to the resistance measuring instrument via a wire. Both the first and second single-hole capillaries are vertically fixed and installed on the cap. The lower ends of both the first and second single-hole capillaries are inserted into the molten salt electrolyte. The first single-hole capillary is located directly below the first single-hole electrode protection tube and the two are coaxially distributed. The second single-hole capillary is located directly below the second single-hole electrode protection tube and the two are coaxially distributed. The first electrode rod passes through the first single-hole capillary, and the lower end of the first electrode rod is inserted into the molten salt electrolyte. The second electrode rod passes through the second single-hole capillary, and the lower end of the second electrode rod is inserted into the molten salt electrolyte.

[0012] When the conductivity cell adopts a single-tube split structure, the cover is respectively provided with a thermocouple through hole, a first single-hole electrode protection tube through hole, and a second single-hole electrode protection tube through hole; the thermocouple is installed and fitted with the thermocouple through hole; the first single-hole capillary is installed and fixedly fitted with the first single-hole electrode protection tube through hole; the second single-hole capillary is installed and fixedly fitted with the second single-hole electrode protection tube through hole.

[0013] A method for measuring the primary crystallization temperature of a molten salt electrolyte, using the aforementioned molten salt electrolyte primary crystallization temperature measuring device, includes the following steps:

[0014] Step 1: Powdered molten salt electrolyte is loaded into a crucible, and then the crucible containing the molten salt electrolyte is placed into a high-temperature furnace. The high-temperature furnace heats the crucible until the molten salt electrolyte is completely melted.

[0015] Step 2: After the molten salt electrolyte has completely melted, attach the cap to the open end of the crucible;

[0016] Step 3: Install the conductivity cell and thermocouple between the cap and the support, and then lower the height of the support until the thermocouple, the first electrode rod and the second electrode rod are all inserted into the molten salt electrolyte.

[0017] Step 4: Connect the first and second electrode rods to the resistance measuring instrument via wires, connect the thermocouple to the temperature measuring instrument via wires, and then connect the resistance measuring instrument and the temperature measuring instrument to the computer;

[0018] Step 5: Lower the heating temperature of the high-temperature furnace so that the temperature of the molten salt electrolyte in the crucible decreases synchronously;

[0019] Step 6: Simultaneously plot the melt resistance curve and melt cooling curve of the molten salt electrolyte with temperature in the computer.

[0020] In step three, when the conductivity cell adopts a dual-unit integrated structure, the installation process of the conductivity cell is as follows: First, the double-hole capillary tube is fixedly installed onto the cover through the double-hole capillary tube perforation. After installation, the double-hole capillary tube is directly inserted into the molten salt electrolyte. Then, the thermocouple and the double-hole electrode protection tube are installed on the bracket. The installed thermocouple is located directly above the thermocouple perforation. The installed double-hole capillary tube perforation and its first and second electrode rods are located directly above the double-hole capillary tube.

[0021] In step three, when the conductivity cell adopts a single-tube split structure, the installation process of the conductivity cell is as follows: First, the first single-hole capillary and the second single-hole capillary are fixedly installed onto the cover through the perforations of the first and second single-hole electrode protection tubes, respectively. After installation, the first and second single-hole capillary tubes are directly inserted into the molten salt electrolyte. Then, the thermocouple, the first single-hole electrode protection tube, and the second single-hole electrode protection tube are installed on the bracket. The installed thermocouple is located directly above the thermocouple perforation. The installed first single-hole electrode protection tube and its first electrode rod are located directly above the first single-hole capillary tube. The installed second single-hole electrode protection tube and its second electrode rod are located directly above the second single-hole capillary tube.

[0022] The beneficial effects of this utility model are:

[0023] This invention relates to a device for measuring the primary crystallization temperature of molten salt electrolytes. It utilizes a conductivity cell to measure the resistance of the molten salt electrolyte and plots a curve showing the change in melt resistance with temperature. When non-conductive crystals precipitate on the electrode surface of the conductivity cell, an inflection point appears on the melt resistance versus temperature curve. The temperature corresponding to this inflection point is the primary crystallization temperature of the molten salt electrolyte. Simultaneously, a thermocouple is used to synchronously measure the melt temperature of the molten salt electrolyte and plot a melt cooling curve. By cross-referencing the melt cooling curve with the melt resistance versus temperature curve, the reliability of identifying the primary crystallization temperature of the molten salt electrolyte is further improved. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a molten salt electrolyte primary crystallization temperature measuring device (the conductivity cell adopts a dual-unit integrated structure) according to the present invention;

[0025] Figure 2 This is a schematic diagram of the structure of a molten salt electrolyte primary crystallization temperature measuring device (the conductivity cell adopts a single-tube split structure) according to the present invention;

[0026] Figure 3 This is a schematic diagram of the combined structure of the cap, bracket, conductivity cell (adopting a double-unit integrated structure) and thermocouple of this utility model;

[0027] Figure 4 This is a schematic diagram of the combined structure of the cap, bracket, conductivity cell (adopting a single-tube split structure) and thermocouple of this utility model;

[0028] Figure 5 The graph shows the change in melt resistance as a function of temperature when NaCl is used as a molten salt electrolyte.

[0029] Figure 6 The melt cooling curve is shown when NaCl is used as a molten salt electrolyte.

[0030] Figure 7The graph shows the change in melt resistance as a function of temperature when MgCl2-KCl-NaCl-AlF3 is used as the molten salt electrolyte.

[0031] Figure 8 The melt cooling curve is shown when MgCl2-KCl-NaCl-AlF3 is used as the molten salt electrolyte.

[0032] In the diagram, 1—high-temperature furnace, 2—crucible, 3—cover, 4—support, 5—conductivity cell, 6—thermocouple, 7—resistance measuring instrument, 8—temperature measuring instrument, 9—computer, 10—first electrode rod, 11—second electrode rod, 12—double-hole electrode protection tube, 13—double-hole capillary tube, 14—first single-hole electrode protection tube, 15—second single-hole electrode protection tube, 16—first single-hole capillary tube, 17—second single-hole capillary tube, 18—thermocouple perforation, 19—double-hole capillary perforation, 20—first single-hole electrode protection tube perforation, 21—second single-hole electrode protection tube perforation, 22—molten salt electrolyte. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0034] like Figures 1-4 As shown, a device for measuring the primary crystallization temperature of a molten salt electrolyte includes a high-temperature furnace 1, a crucible 2, a cover 3, a support 4, a conductivity cell 5, a thermocouple 6, a resistance measuring instrument 7, a temperature measuring instrument 8, and a computer 9. The crucible 2 is placed inside the high-temperature furnace 1 and is used to hold the molten salt electrolyte 22. The cover 3 is fastened to the open end of the crucible 2. The support 4 is fixedly positioned above the high-temperature furnace 1. The conductivity cell 5 and the thermocouple 6 are vertically mounted on the support 4, with their lower ends passing through the cover 3 and inserted into the molten salt electrolyte 22. The upper end of the conductivity cell 5 is electrically connected to the resistance measuring instrument 7 via a wire, and the resistance measuring instrument 7 is electrically connected to the computer 9. The upper end of the thermocouple 6 is electrically connected to the temperature measuring instrument 8 via a wire, and the temperature measuring instrument 8 is electrically connected to the computer 9.

[0035] Specifically, the high-temperature furnace 1 is a top-opening pit furnace, the crucible 2 is a cylindrical graphite crucible, the cover 3 is a disc-shaped graphite cover, the thermocouple 6 is an S-type thermocouple with a temperature measurement deviation of 1.8℃, the resistance measuring instrument 7 is a TH2830 digital bridge, and the temperature measuring instrument 8 is an AI719 temperature controller.

[0036] The conductivity cell 5 adopts a dual-unit integrated structure or a single-tube split structure.

[0037] When the conductivity cell 5 adopts a dual-unit integrated structure, it includes a first electrode rod 10, a second electrode rod 11, a dual-through-hole electrode protection tube 12, and a dual-through-hole capillary tube 13; the dual-through-hole electrode protection tube 12 is vertically fixed on the bracket 4, and the thermocouple 6 is distributed side by side with the dual-through-hole electrode protection tube 12; the first electrode rod 10 and the second electrode rod 11 are respectively fixedly inserted into the two through holes of the dual-through-hole electrode protection tube 12, and the first electrode rod 10, the second electrode rod 11, and the dual-through-hole electrode protection tube 12 are integrated. The prefabricated assembly has the top ends of the first electrode rod 10 and the second electrode rod 11 connected to the resistance measuring instrument 7 via wires; the double-hole capillary tube 13 is vertically fixed on the cover 3 with the lower end of the tube inserted into the molten salt electrolyte 22, the double-hole capillary tube 13 is located directly below the double-hole electrode protection tube 12 and the two are coaxially distributed; the first electrode rod 10 and the second electrode rod 11 respectively pass through the two through holes of the double-hole capillary tube 13, and the lower ends of the rods of the first electrode rod 10 and the second electrode rod 11 are inserted into the molten salt electrolyte 22.

[0038] Specifically, the first electrode rod 10 and the second electrode rod 11 are made of platinum wire, the double-hole electrode protection tube 12 is made of corundum tube, and the double-hole capillary tube 13 is made of hot-pressed or pyrolytic boron nitride ceramic tube.

[0039] When the conductivity cell 5 adopts a dual-unit integrated structure, the cover 3 is provided with a thermocouple perforation 18 and a double-through capillary perforation 19 respectively; the thermocouple 6 is fitted into the thermocouple perforation 18; the double-through electrode protection tube 12 is fitted into the double-through capillary perforation 19.

[0040] When the conductivity cell 5 adopts a single-tube split structure, it includes a first electrode rod 10, a second electrode rod 11, a first single-hole electrode protection tube 14, a second single-hole electrode protection tube 15, a first single-hole capillary tube 16, and a second single-hole capillary tube 17; the first single-hole electrode protection tube 14 and the second single-hole electrode protection tube 15 are both vertically fixed on the bracket 4; the thermocouple 6 is located between the first single-hole electrode protection tube 14 and the second single-hole electrode protection tube 15; the first electrode rod 10 is fixedly inserted into the first single-hole electrode protection tube 14, and the first electrode rod 10 and the first single-hole electrode protection tube 14 are an integral prefabricated assembly, and the top end of the first electrode rod 10 is connected to the resistance measuring instrument 7 through a wire; the second electrode rod 11 is fixedly inserted into the second single-hole electrode protection tube 15, and the second electrode rod 11 and the second single-hole electrode protection tube 17 are connected to the first single-hole electrode protection tube 16. The single-hole electrode protection tube 15 is an integral prefabricated assembly. The top end of the second electrode rod 11 is connected to the resistance measuring instrument 7 via a wire. The first single-hole capillary tube 16 and the second single-hole capillary tube 17 are both vertically fixed and installed on the cover 3. The lower ends of the tubes of the first single-hole capillary tube 16 and the second single-hole capillary tube 17 are inserted into the molten salt electrolyte 22. The first single-hole capillary tube 16 is located directly below the first single-hole electrode protection tube 14 and the two are coaxially distributed. The second single-hole capillary tube 17 is located directly below the second single-hole electrode protection tube 15 and the two are coaxially distributed. The first electrode rod 10 passes through the first single-hole capillary tube 16, and the lower end of the rod of the first electrode rod 10 is inserted into the molten salt electrolyte 22. The second electrode rod 11 passes through the second single-hole capillary tube 17, and the lower end of the rod of the second electrode rod 11 is inserted into the molten salt electrolyte 22.

[0041] When the conductivity cell 5 adopts a single-tube split structure, the cover 3 is respectively provided with a thermocouple through hole 18, a first single-hole electrode protection tube through hole 20, and a second single-hole electrode protection tube through hole 21; the thermocouple 6 is fitted into the thermocouple through hole 18; the first single-hole capillary 16 is fitted into the first single-hole electrode protection tube through hole 20; and the second single-hole capillary 17 is fitted into the second single-hole electrode protection tube through hole 21.

[0042] Specifically, the first electrode rod 10 and the second electrode rod 11 are made of platinum wire, the first single-hole electrode protection tube 14 and the second single-hole electrode protection tube 15 are made of corundum tubes, and the first single-hole capillary tube 16 and the second single-hole capillary tube 17 are made of hot-pressed or pyrolytic boron nitride ceramic tubes.

[0043] A method for measuring the primary crystallization temperature of a molten salt electrolyte, using the aforementioned molten salt electrolyte primary crystallization temperature measuring device, includes the following steps:

[0044] Step 1: Powdered molten salt electrolyte 22 is loaded into crucible 2, and then crucible 2 containing molten salt electrolyte 22 is sent into high-temperature furnace 1. The high-temperature furnace 1 heats crucible 2 until molten salt electrolyte 22 is completely melted.

[0045] Step 2: After the molten salt electrolyte 22 has completely melted, attach the cap 3 to the open end of the crucible 2;

[0046] Step 3: Install the conductivity cell 5 and thermocouple 6 between the cover 3 and the bracket 4 respectively, and then lower the height of the bracket 4 until the thermocouple 6, the first electrode rod 10 and the second electrode rod 11 are all inserted into the molten salt electrolyte 22.

[0047] Step 4: Connect the first electrode rod 10 and the second electrode rod 11 to the resistance measuring instrument 7 through wires, connect the thermocouple 6 to the temperature measuring instrument 8 through wires, and then connect the resistance measuring instrument 7 and the temperature measuring instrument 8 to the computer 9.

[0048] Step 5: Lower the heating temperature of high-temperature furnace 1 so that the temperature of molten salt electrolyte 22 in crucible 2 drops synchronously;

[0049] Step 6: Simultaneously plot the melt resistance curve and melt cooling curve of molten salt electrolyte 22 as a function of temperature in computer 9.

[0050] In step three, when the conductivity cell 5 adopts a dual-unit integrated structure, the installation process of the conductivity cell 5 is as follows: First, the double-hole capillary tube 13 is fixedly installed onto the cover 3 through the double-hole capillary tube through hole 19. After installation, the double-hole capillary tube 13 is directly inserted into the molten salt electrolyte 22. Then, the thermocouple 6 and the double-hole electrode protection tube 12 are installed onto the bracket 4. After installation, the thermocouple 6 is located directly above the thermocouple through hole 18. After installation, the double-hole capillary tube through hole 19 and its first electrode rod 10 and second electrode rod 11 are located directly above the double-hole capillary tube 13.

[0051] In step three, when the conductivity cell 5 adopts a single-tube split structure, the installation process of the conductivity cell 5 is as follows: First, the first single-hole capillary tube 16 and the second single-hole capillary tube 17 are fixedly installed onto the cover 3 through the first single-hole electrode protection tube through hole 20 and the second single-hole electrode protection tube through hole 21, respectively. After installation, the first single-hole capillary tube 16 and the second single-hole capillary tube 17 are directly inserted into the molten salt electrolyte 22. Then, the thermocouple 6, the first single-hole electrode protection tube 14 and the second single-hole electrode protection tube 15 are installed onto the bracket 4. After installation, the thermocouple 6 is located directly above the thermocouple through hole 18. After installation, the first single-hole electrode protection tube 14 and its first electrode rod 10 are located directly above the first single-hole capillary tube 16. After installation, the second single-hole electrode protection tube 15 and its second electrode rod 11 are located directly above the second single-hole capillary tube 17.

[0052] When the molten salt electrolyte 22 is NaCl, the curve of melt resistance versus temperature is as follows: Figure 5 As shown, the melt cooling curve is as follows: Figure 6As shown. From Figure 5 As can be seen, the inflection point of the curve is 802.6℃. Since the temperature measurement deviation of thermocouple 6 is 1.8℃, the measured primary crystallization temperature of NaCl should be 800.8℃. Compared with the standard value of 800.7℃ for the primary crystallization temperature of NaCl, the measurement error is 0.02%. Figure 6 As can be seen, the inflection point temperature of the curve is 802.8℃. Since the temperature measurement deviation of thermocouple 6 is 1.8℃, the actual measured primary crystallization temperature of NaCl should be 801℃. Compared with the standard value of 800.7℃ for the primary crystallization temperature of NaCl, the measurement error is 0.04%. The measurement of the primary crystallization temperature of NaCl fully verifies the effectiveness of this utility model.

[0053] When the molten salt electrolyte 22 is MgCl2-KCl-NaCl-AlF3, the melt resistance as a function of temperature is as follows: Figure 7 As shown, the melt cooling curve is as follows: Figure 8 As shown. From Figure 7 As can be seen, the inflection point of the curve is 458℃. Since the temperature measurement deviation of thermocouple 6 is 1.8℃, the measured primary crystallization temperature of MgCl2-KCl-NaCl-AlF3 should be 456.2℃. Figure 8 As can be seen, the inflection point of the curve is 457.7℃. Since the temperature measurement deviation of thermocouple 6 is 1.8℃, the measured primary crystallization temperature of MgCl2-KCl-NaCl-AlF3 should be 455.9℃. Therefore, the melt cooling curve and the melt resistance versus temperature curve mutually corroborate each other, effectively improving the reliability of identifying the primary crystallization temperature of the molten salt electrolyte.

[0054] The solutions in the embodiments are not intended to limit the scope of protection of this utility model. All equivalent implementations or modifications that do not depart from the scope of protection of this utility model are included in the scope of protection of this utility model.

Claims

1. A device for measuring the primary crystallization temperature of molten salt electrolyte, characterized in that: The system includes a high-temperature furnace, a crucible, a cover, a support, a conductivity cell, a thermocouple, a resistance measuring instrument, a temperature measuring instrument, and a computer. The crucible is placed inside the high-temperature furnace and is used to hold molten salt electrolyte. The cover is fastened to the open end of the crucible. The support is fixedly positioned above the high-temperature furnace. The conductivity cell and thermocouple are vertically mounted on the support, with their lower ends passing through the cover and inserted into the molten salt electrolyte. The upper end of the conductivity cell is electrically connected to the resistance measuring instrument via a wire, and the resistance measuring instrument is electrically connected to the computer. The upper end of the thermocouple is electrically connected to the temperature measuring instrument via a wire, and the temperature measuring instrument is electrically connected to the computer.

2. The molten salt electrolyte primary crystallization temperature measuring device according to claim 1, characterized in that: The conductivity cell adopts a dual-unit integrated structure or a single-tube split structure.

3. The molten salt electrolyte primary crystallization temperature measuring device according to claim 2, characterized in that: When the conductivity cell adopts a dual-unit integrated structure, it includes a first electrode rod, a second electrode rod, a dual-through-hole electrode protection tube, and a dual-through-hole capillary tube; the dual-through-hole electrode protection tube is vertically fixed on a support, and the thermocouple is distributed side by side with the dual-through-hole electrode protection tube; the first electrode rod and the second electrode rod are respectively fixedly inserted into the two through holes of the dual-through-hole electrode protection tube, and the first electrode rod, the second electrode rod, and the dual-through-hole electrode protection tube are an integrated prefabricated assembly, and the top ends of the first electrode rod and the second electrode rod are connected to a resistance measuring instrument through wires; the dual-through-hole capillary tube is vertically fixed on a cap, and the lower end of the tube body is inserted into molten salt electrolyte, the dual-through-hole capillary tube is located directly below the dual-through-hole electrode protection tube, and the two are coaxially distributed; the first electrode rod and the second electrode rod respectively pass through the two through holes of the dual-through-hole capillary tube, and the lower ends of the first electrode rod and the second electrode rod are inserted into molten salt electrolyte.

4. The molten salt electrolyte primary crystallization temperature measuring device according to claim 3, characterized in that: When the conductivity cell adopts a dual-unit integrated structure, the cover is provided with thermocouple perforation and double-through-hole capillary perforation respectively; the thermocouple is fitted into the thermocouple perforation; the double-through-hole electrode protection tube is fitted into the double-through-hole capillary perforation and fixedly fitted.

5. The molten salt electrolyte primary crystallization temperature measuring device according to claim 2, characterized in that: When the conductivity cell adopts a single-tube split structure, it includes a first electrode rod, a second electrode rod, a first single-hole electrode protection tube, a second single-hole electrode protection tube, a first single-hole capillary tube, and a second single-hole capillary tube; both the first and second single-hole electrode protection tubes are vertically fixed on a support; the thermocouple is located between the first and second single-hole electrode protection tubes; the first electrode rod is fixedly inserted into the first single-hole electrode protection tube, and the first electrode rod and the first single-hole electrode protection tube are an integral prefabricated assembly; the top of the first electrode rod is connected to a resistance measuring instrument via a wire; the second electrode rod is fixedly inserted into the second single-hole electrode protection tube, and the second electrode rod and the second single-hole capillary tube are... The single-hole electrode protection tube is an integral prefabricated assembly. The top of the second electrode rod is connected to the resistance measuring instrument via a wire. Both the first and second single-hole capillaries are vertically fixed and installed on the cap. The lower ends of both the first and second single-hole capillaries are inserted into the molten salt electrolyte. The first single-hole capillary is located directly below the first single-hole electrode protection tube and the two are coaxially distributed. The second single-hole capillary is located directly below the second single-hole electrode protection tube and the two are coaxially distributed. The first electrode rod passes through the first single-hole capillary, and the lower end of the first electrode rod is inserted into the molten salt electrolyte. The second electrode rod passes through the second single-hole capillary, and the lower end of the second electrode rod is inserted into the molten salt electrolyte.

6. The molten salt electrolyte primary crystallization temperature measuring device according to claim 5, characterized in that: When the conductivity cell adopts a single-tube split structure, the cover is respectively provided with a thermocouple through hole, a first single-hole electrode protection tube through hole, and a second single-hole electrode protection tube through hole; the thermocouple is installed and fitted with the thermocouple through hole; the first single-hole capillary is installed and fixedly fitted with the first single-hole electrode protection tube through hole; the second single-hole capillary is installed and fixedly fitted with the second single-hole electrode protection tube through hole.

Images