A graphite anode baking furnace for rare earth electrolysis

Abstract

The present invention provides a graphite anode baking furnace for rare earth electrolysis, comprising a baking furnace body and a control cabinet. It is characterized in that the baking furnace body includes a cylinder body and a heating element; a chamber for accommodating the heating element is arranged inside the cylinder body, and the heating element is detachably arranged in the chamber; the heating element includes a conductive connection block, a refractory insulating column, a conductive base, a large insulating plate and two small insulating plates; by means of low-voltage direct current, the graphite anode plates form a series circuit and rely on their own resistance to heat and bake themselves. The method is simple, the heating is uniform and thorough, and the efficiency is high. Compared with the traditional large muffle furnace technology, the energy saving is obvious, which is not only beneficial to reducing production costs, but also beneficial to energy conservation and consumption reduction, has high economic benefits, and meets the green development requirements of energy conservation and emission reduction.

Description

Technical Field

[0001] The invention relates to the technical field of graphite anode sheet drying furnaces, in particular to a graphite anode sheet drying furnace for rare earth electrolysis. Background Art

[0002] The production of rare earth metals mainly adopts molten salt electrolysis, and the device used is an electrolytic cell, which is mainly composed of graphite anode, tungsten cathode, graphite crucible, platen, etc. During the rare earth electrolysis process, the temperature of the electrolytic furnace directly affects the qualified rate of rare earth metals, especially the carbon content in the metal. If the furnace temperature is low, it is easy to cause high metal carbon. The reason is that as the rare earth electrolysis proceeds, the anode will be continuously consumed, and it needs to be continuously replaced with a new graphite anode. During the replacement process, due to the interruption of the electrolysis process, the molten salt in the furnace will lose a lot of heat and cannot be replenished in time. At this time, the temperature will drop significantly, and the carbon accumulated in the molten salt will not be easy to volatilize, and it is easy to react with the metal to form rare earth carbide or be mixed in the metal, resulting in excessive metal carbon content. Under normal circumstances, the use of a large muffle furnace to bake anode sheets has low efficiency, slow heating speed, high energy consumption, and is not conducive to energy conservation and environmental protection and reducing production costs.

[0003] The Chinese invention patent with publication number CN114353512A discloses a muffle furnace, including a bottom wall, a side wall and a cover body, the side wall is cylindrical, the bottom end of the side wall is connected to the bottom wall, the cover body covers the top of the side wall, the inner side of the side wall is provided with a heating assembly and a furnace, the upper end of the furnace is embedded with an inner cover, the inner cover can rotate at the upper end of the furnace, the inner cover is provided with a mouth, and the mouth is filled with an inner plug. This application has low baking efficiency and slow speed when baking graphite anode sheets for rare earth metal production, wasting a lot of energy. Summary of the invention

[0004] In view of the above-mentioned technical deficiencies, the purpose of the present invention is to provide a graphite anode sheet drying furnace for rare earth electrolysis, which utilizes the resistance of the graphite anode sheet itself to generate heat to achieve the purpose of heating and baking the graphite anode sheet.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] A graphite anode baking furnace for rare earth electrolysis, comprising a baking furnace body and a control cabinet. The baking furnace body includes a cylinder body and a heating element. A chamber for accommodating the heating element is arranged inside the cylinder body, and the heating element is detachably arranged in the chamber. The heating element includes a conductive connection block, a refractory insulating column, a conductive base, a large insulating plate and two small insulating plates. The large insulating plate vertically penetrates the conductive base. The large insulating plate divides the conductive base into a left conductive seat and a right conductive seat which are symmetrically arranged. The lower end surface of the refractory insulating column abuts against the upper end surface of the conductive base. A first groove for accommodating the large insulating plate and a second groove perpendicular to the first groove are arranged at the lower part of the refractory insulating column. The two small insulating plates are respectively arranged on both sides of the large insulating plate and are clamped in the second groove. The large insulating plate and the two small insulating plates divide the external space of the refractory insulating column into a first quadrant space, a second quadrant space, a third quadrant space and a fourth quadrant space. A connecting groove for accommodating the conductive connection block is arranged at the top of the refractory insulating column. The connecting groove communicates with the first quadrant space and the third quadrant space. The conductive connection block is clamped in the connecting groove. An arc-shaped graphite anode plate is arranged in each of the first quadrant space, the second quadrant space, the third quadrant space and the fourth quadrant space. The four graphite anode plates are circumferentially arranged at equal angles with the axis of the refractory insulating column as the center. The bottom end surface of the graphite anode plate contacts the upper end surface of the conductive base. The inner side surfaces of the graphite anode plates in the first quadrant space and the third quadrant space respectively contact both ends of the conductive connection block. Two wiring posts are fixedly arranged inside the cylinder body. The bottom end surfaces of the two wiring posts respectively contact the top end surfaces of the graphite anode plates arranged in the second quadrant space and the fourth quadrant space. The wiring posts are connected to the control cabinet through electric wires.

[0007] Preferably, the cylinder body includes a support plate, a heat insulation pad and a coaxial outer shell, a heat insulation layer and a refractory skeleton. The heat insulation layer is arranged between the outer shell and the refractory skeleton. The outer side surface of the heat insulation layer is attached to the inner side surface of the outer shell. The inner side surface of the heat insulation layer is attached to the outer side surface of the refractory skeleton. The support plate and the heat insulation pad are arranged inside the outer shell. The upper end surface of the support plate contacts the lower end surface of the heat insulation layer. The upper end surface of the heat insulation pad contacts the lower end surface of the support plate, and the lower end surface contacts the outer shell. The lower end surface of the conductive base contacts the upper end surface of the support plate.

[0008] Preferably, the cylinder body includes a cylinder cover and a cylinder body. The wiring post is arranged inside the cylinder cover. A thermocouple is fixedly arranged inside the cylinder cover. The thermocouple is electrically connected to the control cabinet. A first connecting ear plate is fixedly arranged on the outer side surface of the bottom of the cylinder cover. A second connecting ear plate is fixedly arranged on the outer side surface of the top of the cylinder body. The first connecting ear plate and the second connecting ear plate are hinged.

[0009] Preferably, the refractory insulating column is fixedly arranged inside the cylinder body, and the upper end of the refractory insulating column extends upward to the outside of the cylinder body.

[0010] Preferably, clamping grooves adapted to the small insulating plate are provided on both the left conductive base and the right conductive base; the bottom of the small insulating plate is clamped in the clamping grooves.

[0011] Preferably, a temperature display controller and a power supply are configured on the control cabinet.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0013] Compared with the prior art, the present invention forms a series circuit with graphite anode plates through low-voltage direct current, and relies on its own resistance to heat and bake itself. The method is simple, the heating is uniform and thorough, and the efficiency is high. Compared with the traditional large muffle furnace technology, the energy saving is obvious, which is not only beneficial to reducing production costs, but also beneficial to energy conservation and consumption reduction, has high economic benefits, and meets the green development requirements of energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic structural diagram of the present invention;

[0015] Figure 2 is a schematic structural diagram of the baking furnace body of the present invention with graphite anode plates installed;

[0016] Figure 3 is a schematic structural diagram of the baking furnace body of the present invention;

[0017] Figure 4 is a schematic connection diagram of the heating element and the graphite anode plate of the present invention;

[0018] Figure 5 is a structural exploded view of the heating element of the present invention.

[0019] Wherein:

[0020] 1, heat preservation pad; 2, conductive base; 201, left conductive base; 202, right conductive base; 3, refractory skeleton; 4, small insulating plate; 5, terminal; 6, outer shell; 7, heat preservation layer; 8, electric wire; 9, temperature display controller; 10, control cabinet; 11, conductive connection block; 12, sealing ring; 13, refractory insulating column; 14, large insulating plate; 15, support plate; 16, cylinder cover; 17, cylinder body; 18, thermocouple; 19, graphite anode plate; 20, first connecting ear plate; 21, second connecting ear plate; 22, clamping groove; 23, first groove; 24, connecting groove; 25, second groove. DETAILED DESCRIPTION OF THE INVENTION

[0021] The present invention will be further described below with reference to the accompanying drawings.

[0022] As Figures 1 to 5As shown in the figure, a graphite anode baking furnace for rare earth electrolysis includes a baking furnace body and a control cabinet 10. The baking furnace body includes a cylinder and a heating element. The cylinder mainly plays a heat preservation role, and the heating element plays a role in heating and drying. The shape of the cylinder is cylindrical. There is a chamber inside the cylinder for accommodating the heating element, and the heating element is detachably arranged in the chamber. The heating element includes a conductive connection block 11, a refractory insulating column 13, a conductive base 2, a large insulating plate 14, and two small insulating plates 4. The main materials of the conductive connection block 11 and the conductive base 2 are graphite. The materials of the refractory insulating column 13, the large insulating plate 14, and the small insulating plate 4 are corundum. The large insulating plate 14 and the small insulating plates 4 both have insulating properties. The conductive connection block 11 has electrical conductivity. The conductive base 2 is cylindrical. The large insulating plate 14 vertically penetrates the conductive base 2 downward from the upper direction of the conductive base 2. The large insulating plate 14 divides the conductive base 2 into a symmetrically arranged left conductive seat 201 and a right conductive seat 202, and the left conductive seat 201 and the right conductive seat 202 are not connected to each other after being separated by the large insulating plate 14. The lower end surface of the refractory insulating column 13 abuts against and is fixedly connected to the upper end surface of the conductive base 2. The refractory insulating column 13 is coaxially arranged with the conductive base 2. The diameter of the refractory insulating column 13 is smaller than the diameter of the conductive base 2. A first groove 23 for accommodating the large insulating plate 14 and a second groove 25 perpendicular to the first groove 23 are provided at the lower part of the refractory insulating column 13. The first groove 23 and the second groove 25 intersect at the axis of the refractory insulating column 13. The two small insulating plates 4 are respectively arranged on both sides of the large insulating plate 14 and are clamped in the second groove 25. The large insulating plate 14 and the two small insulating plates 4 divide the external space of the refractory insulating column 13 into a first quadrant space, a second quadrant space, a third quadrant space, and a fourth quadrant space. A connection groove 24 for accommodating the conductive connection block 11 is provided at the top of the refractory insulating column 13. The connection groove 24 communicates with the first quadrant space and the third quadrant space. The conductive connection block 11 is clamped in the connection groove 24. An arc-shaped graphite anode plate 19 is provided in each of the first quadrant space, the second quadrant space, the third quadrant space, and the fourth quadrant space. The four graphite anode plates 19 are circumferentially arrayed at equal angles with the axis of the refractory insulating column 13 as the center. Adjacent two graphite anode plates 19 are separated by the large insulating plate 14 and the small insulating plates 4 and do not contact each other. The bottom end surface of the graphite anode plate 19 contacts the upper end surface of the conductive base 2. The inner side surfaces of the graphite anode plates 19 in the first quadrant space and the third quadrant space respectively contact the two ends of the conductive connection block 11, so that the four graphite anode plates 19 are connected in series. Two wiring posts 5 are fixedly arranged inside the cylinder. The bottom end surfaces of the two wiring posts 5 respectively contact the top end surfaces of the graphite anode plates 19 arranged in the second quadrant space and the fourth quadrant space. The wiring posts 5 are connected to the control cabinet 10 through electric wires 8.The current is transmitted from the control cabinet 10 through one of the terminal posts 5 to the graphite anode plate 19 in the second quadrant space, and then downward along the graphite anode plate 19 to the left conductive seat 201 / right conductive seat 202. Then, it is transmitted through the left conductive seat 201 / right conductive seat 202 to the graphite anode plate 19 in the first quadrant space, and through the conductive connection block 11 to the graphite anode plate 19 in the third quadrant space. It is transmitted downward to the right conductive seat 202 / left conductive seat 201, and then to the graphite anode plate 19 in the fourth quadrant space, and is conveyed back to the control cabinet 10 through the other terminal post 5. The graphite anode plate 19 is heated by the action of the current to achieve self-heating and baking.

[0023] Furthermore, the cylinder body includes a support plate 15, a heat insulation pad 1, and a housing 6, a heat insulation layer 7, and a refractory skeleton 3 arranged coaxially; the heat insulation layer 7 is arranged between the housing 6 and the refractory skeleton 3; the outer side surface of the heat insulation layer 7 is attached to the inner side surface of the housing 6; the inner side surface of the heat insulation layer 7 is attached to the outer side surface of the refractory skeleton 3; the support plate 15 and the heat insulation pad 1 are arranged inside the housing 6; the upper end surface of the support plate 15 is in contact with the lower end surface of the heat insulation layer 7; the upper end surface of the heat insulation pad 1 is in contact with the lower end surface of the support plate 15, and the lower end surface is in contact with the housing 6; the lower end surface of the conductive base 2 is in contact with the upper end surface of the support plate 15; the materials of the support plate 15 and the refractory skeleton 3 are mainly corundum, and the material of the heat insulation pad 1 is heat insulation brick.

[0024] Furthermore, the cylinder body includes a cylinder cover 16 and a cylinder body 17; the terminal post 5 is arranged inside the cylinder cover 16; a thermocouple 18 is fixedly arranged inside the cylinder cover 16; the thermocouple 18 is electrically connected to the control cabinet 10; the outer side surface of the bottom of the cylinder cover 16 is fixedly provided with a first connecting ear plate 20; the outer side surface of the top of the cylinder body 17 is fixedly provided with a second connecting ear plate 21; the first connecting ear plate 20 and the second connecting ear plate 21 are hinged; sealing rings 12 are respectively arranged at the joints of the cylinder cover 16 and the cylinder body 17; when the cylinder cover 16 is closed on the cylinder body 17, the two terminal posts 5 are respectively abutted against the corresponding graphite anode plates 19, so as to realize that the four graphite anode plates 19 form a series circuit.

[0025] Furthermore, the refractory insulating column 13 is fixedly arranged inside the cylinder body 17; the upper end of the refractory insulating column 13 extends upward to the outside of the cylinder body 17.

[0026] Furthermore, the left conductive seat 201 and the right conductive seat 202 are both provided with slots 22 adapted to the small insulating plate 4; the bottom of the small insulating plate 4 is clamped in the slots 22.

[0027] Furthermore, a temperature display controller 9 and a power supply are configured on the control cabinet 10; the temperature display controller 9 is built-in with time, temperature, current, voltage and working mode; the heating element is controlled by a thermocouple 18 to work. After the graphite anode plate 19 is self-heated to the set temperature, it switches to the heat preservation state; the set temperature for the heating element to work should be greater than 150 °C to ensure that the anode plate is completely dehumidified; the power supply adopts a low-voltage DC rectifier power supply with a voltage lower than 12V and a current lower than 5000A.

[0028] During the rare earth electrolysis process, when the anode of the electrolytic cell is approaching replacement, baking of the anode plate should be carried out at least 1 hour in advance. Open the cylinder cover 16 of the baking furnace, put in four graphite anode plates 19, place the conductive connection block 11 into the connection groove 24 at the upper part of the refractory insulating column 13, clamp the graphite anode plate 19 tightly, close the cylinder cover 16, and press the two terminal posts 5 on its upper part against the graphite anode plate 19 to ensure good contact. Turn on the power supply, set the temperature, current, voltage and working mode through the temperature display controller 9, and automatically switch to the heat preservation mode after reaching the set temperature. When replacing the graphite anode plate 19, turn off the power supply, open the cylinder cover 16, take out the graphite anode plate 19, replace the anode of the electrolytic cell, and then continue to bake the graphite anode plate 19 according to the production situation.

Claims

1. A graphite anode baking furnace for rare earth electrolysis, comprising a baking furnace body and a control cabinet (10). It is characterized in that the baking furnace body includes a cylinder body and a heating element; a chamber for accommodating the heating element is arranged inside the cylinder body, and the heating element is detachably arranged in the chamber; the heating element includes a conductive connection block (11), a refractory insulating column (13), a conductive base (2), a large insulating plate (14) and two small insulating plates (4); the large insulating plate (14) vertically penetrates through the conductive base (2); the large insulating plate (14) divides the conductive base (2) into a symmetrically arranged left conductive seat (201) and right conductive seat (202); the lower end surface of the refractory insulating column (13) abuts against the upper end surface of the conductive base (2); a first groove (23) for accommodating the large insulating plate (14) and a second groove (25) perpendicular to the first groove (23) are arranged at the lower part of the refractory insulating column (13); the two small insulating plates (4) are respectively arranged on both sides of the large insulating plate (14) and are clamped in the second groove (25); the large insulating plate (14) and the two small insulating plates (4) divide the external space of the refractory insulating column (13) into a first quadrant space, a second quadrant space, a third quadrant space and a fourth quadrant space; a connecting groove (24) for accommodating the conductive connection block (11) is arranged at the top of the refractory insulating column (13); the connecting groove (24) communicates with the first quadrant space and the third quadrant space; the conductive connection block (11) is clamped in the connecting groove (24); an arc-shaped graphite anode plate (19) is arranged in each of the first quadrant space, the second quadrant space, the third quadrant space and the fourth quadrant space, and the four graphite anode plates (19) are circumferentially arrayed at equal angles with the axis of the refractory insulating column (13) as the center; the bottom end surface of the graphite anode plate (19) is in contact with the upper end surface of the conductive base (2); the inner side surfaces of the graphite anode plates (19) in the first quadrant space and the third quadrant space are respectively in contact with both ends of the conductive connection block (11); two wiring posts (5) are fixedly arranged inside the cylinder body; the bottom end surfaces of the two wiring posts (5) are respectively in contact with the top end surfaces of the graphite anode plates (19) arranged in the second quadrant space and the fourth quadrant space; the wiring posts (5) are connected to the control cabinet (10) through electric wires (8). The cylinder body includes a support plate (15), a heat preservation pad (1) and a coaxial outer shell (6), a heat preservation layer (7), a refractory skeleton (3); the heat preservation layer (7) is arranged between the outer shell (6) and the refractory skeleton (3); the outer side surface of the heat preservation layer (7) is attached to the inner side surface of the outer shell (6); the inner side surface of the heat preservation layer (7) is attached to the outer side surface of the refractory skeleton (3); the support plate (15) and the heat preservation pad (1) are arranged inside the outer shell (6); the upper end surface of the support plate (15) is in contact with the lower end surface of the heat preservation layer (7); the upper end surface of the heat preservation pad (1) is in contact with the lower end surface of the support plate (15), and the lower end surface is in contact with the outer shell (6); the lower end surface of the conductive base (2) is in contact with the upper end surface of the support plate (15). The left conductive seat (201) and the right conductive seat (202) are both provided with a card slot (22) adapted to the small insulating plate (4); the bottom of the small insulating plate (4) is snap-fitted in the card slot (22).

2. A graphite anode baking furnace for rare earth electrolysis according to claim 1, characterized in that the cylinder body includes a cylinder cover (16) and a cylinder body (17); the terminal post (5) is arranged inside the cylinder cover (16); a thermocouple (18) is fixedly arranged inside the cylinder cover (16); the thermocouple (18) is electrically connected to the control cabinet (10); a first connecting ear plate (20) is fixedly arranged on the outer side of the bottom of the cylinder cover (16); a second connecting ear plate (21) is fixedly arranged on the outer side of the top of the cylinder body (17); the first connecting ear plate (20) and the second connecting ear plate (21) are hinged.

3. A graphite anode baking furnace for rare earth electrolysis according to claim 2, characterized in that the refractory insulating column (13) is fixedly arranged inside the cylinder body (17); the upper end of the refractory insulating column (13) extends upward to the outside of the cylinder body (17).

4. A graphite anode baking furnace for rare earth electrolysis according to claim 1, characterized in that the control cabinet (10) is configured with a temperature display controller (9) and a power supply.

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