Production process of graphite tile for electrolyzing rare earth

Abstract

The invention belongs to the field of graphite tiles, and particularly relates to a production process of a graphite tile for electrolyzing rare earth, which comprises the following steps: weighing graphitized thermal insulation materials with different finenesses, including 10-16 parts by mass of large materials, 23-30 parts by mass of medium materials, 32-38 parts by mass of small materials and 20-26 parts by mass of powder materials, and uniformly mixing the raw materials to obtain a primary mixture; weighing 22-31 parts of modified liquid asphalt and 69-78 parts of the primary mixture, and performing secondary uniform mixing on the modified liquid asphalt and the primary mixture to obtain a secondary mixture; the secondary mixture is poured into a female die to be heated and subjected to compression molding, and a crucible-shaped graphite semi-finished product is obtained; cutting the bottom of the crucible-shaped semi-finished product to obtain a graphite cylinder, and then slitting the graphite cylinder by using a cutting machine to obtain the 1 / 4 cylindrical graphite tile, so that the electrochemical performance and physical stability of the graphite tile are optimized, the oxidation of the graphite tile is reduced, the service life is prolonged, and the stability and efficiency of the electrolysis process are improved.

Description

Technical Field

[0001] The invention belongs to the field of graphite tiles, and in particular relates to a production process of graphite tiles for electrolytic rare earth. Background Art

[0002] Graphite tiles are widely used as anodes in electrolytic furnaces for electrolysis of rare earth metals. The arc-shaped graphite products formed by four quarter-cylindrical graphite tiles are used as anodes to conduct electricity and reduce, replacing rare earth metals or alloys. During the rare earth molten salt electrolysis process, graphite tiles will react with gases such as oxygen and carbon dioxide, resulting in oxidation and damage of graphite tiles, which not only consumes graphite materials, but also affects the normal operation of the electrolytic cell, thereby affecting the stability and efficiency of the electrolysis process and increasing production costs. Summary of the invention

[0003] In order to solve the problems existing in the above-mentioned prior art, the present invention provides a production process of graphite tiles for electrolytic rare earths, which optimizes the electrochemical properties and physical stability of the graphite tiles by controlling the size and uniform distribution of the particles of the graphitized thermal insulation material, reduces the oxidation of the graphite tiles, prolongs the service life, and improves the stability and efficiency of the electrolysis process.

[0004] The specific technical solution adopted by the present invention is:

[0005] A production process of graphite tiles for electrolytic rare earth includes the following steps:

[0006] S1. Select raw materials, weigh graphitized thermal insulation materials of different finenesses, including 10-16 parts of large materials with a fineness of 3-6mm, 23-30 parts of medium materials with a fineness of 2-3mm, 32-38 parts of small materials with a fineness of 1-2mm, and 20-26 parts of powder materials with a fineness of 0.075-1mm, by weight, and mix the raw materials evenly to obtain a primary mixture; weigh 22-31 parts of reformed liquid asphalt and 69-78 parts of the primary mixture by weight, and mix the reformed liquid asphalt and the primary mixture for a second time to obtain a secondary mixture;

[0007] S2, pouring the secondary mixture into a concave mold for heating and pressing to obtain a crucible-shaped graphite semi-finished product;

[0008] S3, cutting the bottom of the crucible-shaped semi-finished product to obtain a graphite cylinder, and then using a cutting machine to cut the graphite cylinder into 1 / 4 cylinder graphite tiles.

[0009] In the step S1, the graphitized thermal insulation material, calculated by mass, includes 14 parts of large materials with a fineness of 3-6mm, 28 parts of medium materials with a fineness of 2-3mm, 35 parts of small materials with a fineness of 1-2mm, and 23 parts of powder materials with a fineness of 0.075-1mm; calculated by mass, 25 parts of reformed liquid asphalt and 75 parts of primary mixture are weighed, and the reformed liquid asphalt and the primary mixture are mixed for a second time to obtain a secondary mixture.

[0010] In step S1, the large material, medium material, small material and powder material are all ball-milled powders.

[0011] The cutting machine includes a guide positioning component, a four-wire saw component and a clamping component for clamping a graphite cylinder. The positioning point on the guide positioning component is arranged in contact with the side wall of the graphite cylinder to form a positioning ring. The four-wire saw component includes a first saw rope and a second saw rope arranged in a cross shape and a driving unit respectively connected to the first saw rope and the second saw rope. The clamping component and the four-wire saw component have the freedom of relative movement along the axial direction of the positioning ring. The clamping component is respectively arranged between the first saw rope and the second saw rope along the circumferential direction of the positioning ring, and the axis of the positioning ring passes through the first saw rope and the second saw rope respectively.

[0012] The guide and positioning assembly includes a fixed shaft with a group of first hinged rods thereon, and a sliding sleeve sleeved on the fixed shaft and with a second hinged rod. The first hinged rod and the second hinged rod are hinged to each other. The end of the first hinged rod or the second hinged rod extends outward from the hinge point and the positioning point is located at the end to fit the inner wall of the graphite cylinder.

[0013] The end of the second hinged rod extends outward from the hinge point, and a rotating wheel is arranged at the end of the second hinged rod. The rotating wheel fits with the inner wall of the graphite cylinder to form a positioning point.

[0014] The clamping assembly includes a main axial slide rail, a radial slide rail arranged on the main axial slide rail, a secondary axial slide rail and clamps respectively located at both ends of the graphite cylinder. The clamps are respectively arranged on the secondary axial slide rails. The clamps have the freedom to move radially toward the graphite cylinder along the positioning ring with the help of the radial slide rails, and the clamps have the freedom to move axially along the positioning ring with the help of the secondary axial slide rails.

[0015] A fixing seat with a guide slide hole is fixedly connected to the guide positioning component, and guide slide blocks matching the guide slide holes are fixedly connected to the first saw rope and the second saw rope respectively.

[0016] The beneficial effects of the present invention are:

[0017] The present invention increases the proportion of small materials in the primary mixture and reduces the proportion of powder materials in the primary mixture by controlling the proportion of large materials, medium materials, small materials and powder materials in the raw materials, and the proportion with the reformed liquid asphalt, thereby optimizing the electrochemical properties and physical stability of graphite tiles, reducing the oxidation of graphite tiles, and extending the service life; improving the density of graphite tiles, reducing the penetration of molten salt, thereby protecting the graphite tiles from erosion, and at the same time enhancing the structural stability of the graphite tiles, reducing the occurrence of cracking or peeling of graphite tiles, and significantly improving the durability and stability of the graphite tiles during the electrolysis process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the cutting machine in the present invention;

[0019] Figure 2 for Figure 1 Left view of

[0020] Figure 3 It is a structural schematic diagram of the guide positioning component;

[0021] Figure 4 Schematic diagram of the state of the cutting machine cutting a graphite cylinder;

[0022] Figure 5 It is a structural diagram of graphite tiles;

[0023] In the attached drawings, 1, graphite cylinder, 2, graphite tile, 3, positioning ring, 4, first saw rope, 5, second saw rope, 6, first hinged rod, 7, fixed shaft, 8, second hinged rod, 9, sliding sleeve, 10, rotating wheel, 11, main axial slide rail, 12, radial slide rail, 13, secondary axial slide rail, 14, splint, 15, guide slide block, 16, fixed seat. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments:

[0025] Specific embodiment, the present invention relates to a production process of graphite tiles for electrolytic rare earth, comprising the following steps:

[0026] S1. Select raw materials, weigh graphitized thermal insulation materials of different finenesses, including 14 parts of large materials with a fineness of 3-6mm, 28 parts of medium materials with a fineness of 2-3mm, 35 parts of small materials with a fineness of 1-2mm, and 23 parts of powder materials with a fineness of 0.075-1mm, by weight, and mix the raw materials evenly to obtain a primary mixture; weigh 25 parts of reformed liquid asphalt and 75 parts of the primary mixture by weight, and mix the reformed liquid asphalt and the primary mixture for a second time to obtain a secondary mixture; wherein the large material, medium material, small material and powder are all ball-milled powders;

[0027] S2, pouring the secondary mixture into a concave mold for heating and pressing to obtain a crucible-shaped graphite semi-finished product;

[0028] S3, cutting the bottom of the crucible-shaped semi-finished product to obtain a graphite cylinder 1, and then using a cutting machine to cut the graphite cylinder 1 into 1 / 4 cylinder graphite tiles 2.

[0029] Embodiment 2, a production process of graphite tiles for electrolytic rare earth, comprising the following steps:

[0030] S1. Select raw materials, weigh graphitized thermal insulation materials of different finenesses, including 11 parts of large materials with a fineness of 3-6mm, 29 parts of medium materials with a fineness of 2-3mm, 38 parts of small materials with a fineness of 1-2mm, and 22 parts of powder materials with a fineness of 0.075-1mm, by weight, and mix the raw materials evenly to obtain a primary mixture; weigh 22 parts of reformed liquid asphalt and 78 parts of the primary mixture by weight, and mix the reformed liquid asphalt and the primary mixture for a second time to obtain a secondary mixture; wherein the large material, medium material, small material and powder are all ball-milled powders;

[0031] S2, pouring the secondary mixture into a concave mold for heating and pressing to obtain a crucible-shaped graphite semi-finished product;

[0032] S3, cutting the bottom of the crucible-shaped semi-finished product to obtain a graphite cylinder 1, and then using a cutting machine to cut the graphite cylinder 1 into 1 / 4 cylinder graphite tiles 2.

[0033] Embodiment 3, a production process of graphite tiles for electrolytic rare earth, comprising the following steps:

[0034] S1. Select raw materials, weigh graphitized thermal insulation materials of different finenesses, including 16 parts of large materials with a fineness of 3-6mm, 30 parts of medium materials with a fineness of 2-3mm, 32 parts of small materials with a fineness of 1-2mm, and 22 parts of powder materials with a fineness of 0.075-1mm, by weight, and mix the raw materials evenly to obtain a primary mixture; weigh 30 parts of reformed liquid asphalt and 70 parts of the primary mixture by weight, and mix the reformed liquid asphalt and the primary mixture for a second time to obtain a secondary mixture; wherein the large material, medium material, small material and powder are all ball-milled powders;

[0035] S2, pouring the secondary mixture into a concave mold for heating and pressing to obtain a crucible-shaped graphite semi-finished product;

[0036] S3, cutting the bottom of the crucible-shaped semi-finished product to obtain a graphite cylinder 1, and then using a cutting machine to cut the graphite cylinder 1 into 1 / 4 cylinder graphite tiles 2.

[0037] The graphite tiles cut into pieces with a diameter of 500 mm in a crucible state were used as samples, and three groups of test samples were prepared in each treatment method of Examples 1-3.

[0038]

[0039]

[0040] It can be seen that the wear resistance and oxidation resistance of the graphite tiles prepared by the production process of graphite tiles for electrolytic rare earth provided by the present invention are significantly improved, thereby extending the service life of the graphite tiles, reducing the replacement frequency, and reducing the production cost of electrolytic rare earth.

[0041] Embodiment 4, as Figure 1-5 As shown, the cutting machine used in step S3 of embodiment 1-3 includes a guide positioning assembly, a four-wire saw assembly and a clamping assembly for clamping the graphite cylinder 1. The positioning point on the guide positioning assembly is arranged in contact with the side wall of the graphite cylinder 1 to form a positioning ring 3. The four-wire saw assembly includes a first saw rope 4 and a second saw rope 5 arranged in a cross shape and a driving unit connected to the first saw rope 4 and the second saw rope 5 respectively. The clamping assembly and the four-wire saw assembly have the freedom of relative movement along the axial direction of the positioning ring 3. The clamping assembly is respectively arranged between the first saw rope 4 and the second saw rope 5 along the circumferential direction of the positioning ring 3, and the axis of the positioning ring 3 passes through the first saw rope 4 and the second saw rope 5 respectively. The driving unit is a motor, a driving gear and a driven wheel of a commercially available wire saw.

[0042] During operation, the graphite cylinder 1 is sleeved on the guide positioning assembly for positioning, the positioning ring 3 coincides with the inner wall of the graphite cylinder 1, and after positioning is completed, the graphite cylinder 1 is clamped by the clamping assembly, and the four-wire saw assembly or the clamping assembly moves along the axial direction of the positioning ring 3, so that the graphite cylinder 1 passes through the four-wire saw assembly, and the four-wire saw assembly divides the graphite cylinder 1 into four; because the first saw rope 4 and the second saw rope 5 are cross-shaped, and the first saw rope 4 and the second saw rope 5 form an angle of 90 degrees, the axis of the positioning ring 3 passes through the first saw rope 4 and the second saw rope 5 respectively, that is, the first saw rope 4 and the second saw rope 5 are located on two mutually perpendicular radial lines of the graphite cylinder 1, when the graphite cylinder 1 passes through the four-wire saw assembly, the four-wire saw divides the graphite cylinder 1 into four equal parts, the cutting efficiency is high, the cut graphite tiles 2 are uniform in size, and the product quality is improved.

[0043] Furthermore, the guide positioning assembly includes a fixed shaft 7 with a group of first hinged rods 6 thereon, and a sliding sleeve 9 sleeved on the fixed shaft 7 and with a second hinged rod 8, the first hinged rod 6 is hinged to the fixed shaft 7, the second hinged rod 8 is hinged to the sliding sleeve 9, the first hinged rod 6 and the second hinged rod 8 are hinged to each other, the end of the first hinged rod 6 or the second hinged rod 8 extends outward from the hinge point between the two and the positioning point is located at the end and fits with the inner wall of the graphite cylinder 1; in this embodiment, the end of the second hinged rod 8 extends outward from the hinge point, pushes the sliding sleeve 9 along the fixed shaft 7, and the first hinged rod 6 and the second hinged rod 8 are hinged to each other. By rotating, the end of the second hinged rod 8 can be opened and closed to meet the positioning of graphite cylinders 1 of different inner diameters; a rotating wheel 10 is provided at the end of the second hinged rod 8, and the rotating wheel 10 fits with the inner wall of the graphite cylinder 1 to form a positioning point. When the graphite cylinder 1 is cut and moves axially along the graphite cylinder 1 with the guide positioning component, the rotating wheel 10 rotates with the movement of the graphite cylinder 1, and can guide the graphite cylinder 1 while positioning, avoiding hard friction inside the graphite cylinder 1, keeping the inner wall of the graphite cylinder 1 smooth and complete, which is helpful to improve the stability of the graphite tile 2 during the electrolysis process and extend the service life of the graphite tile 2.

[0044] The clamping assembly includes a main axial slide rail 11, a radial slide rail 12 arranged on the main axial slide rail 11, a secondary axial slide rail 13 and clamping plates 14 respectively located at both ends of the graphite cylinder 1, wherein the bottom of the radial slide rail 12 forms a guide sliding fit with the main axial slide rail 11, and the bottom of the secondary axial slide rail 13 forms a guide sliding fit with the radial slide rail 12, and the two clamping plates 14 are respectively arranged on the secondary axial slide rail 13, and the clamping plates 14 have the freedom to move along the radial direction of the positioning ring 3 toward the graphite cylinder 1 by means of the radial slide rail 12, and the clamping plates 14 have the freedom to move along the axial direction of the positioning ring 3 by means of the secondary axial slide rail 13; after the graphite cylinder 1 is positioned with the help of the guide positioning assembly, the axial position of the graphite cylinder 1 is fixed, the secondary axial slide rail 12 approaches the graphite cylinder 1 along the radial slide rail 12, and the two clamping plates 14 move toward the two ends of the graphite cylinder 1 along the secondary axial slide rail 13 respectively and cooperate with each other to clamp and fix the graphite cylinder 1. Subsequently, under the clamping of the graphite cylinder 1 by the two clamping plates 14, the radial slide rail 12 moves along the main axial slide rail 11, so that the graphite cylinder 1 is cut through the four-wire saw assembly.

[0045] The clamping position of the clamping plate 14 on the graphite cylinder 1 , the first saw rope 4 , the second saw rope 5 and the rotating wheel 10 are uniformly arranged along the circumference of the graphite cylinder 1 .

[0046] Furthermore, a fixed seat 16 with a guide slide hole is fixedly connected to the guide positioning assembly, and a guide slide block 15 matching the guide slide hole is fixedly connected to the first saw rope 4 and the second saw rope 5 respectively. During operation, the first saw rope 4 and the second saw rope 5 produce reciprocating motion, and the guide slide block 15 forms a guide slide matching with the guide slide hole on the fixed seat 16, which guides the movement of the first saw rope 4 and the second saw rope 5, improves the accuracy of the cutting position, and provides support for the first saw rope 4 and the second saw rope 5.

[0047] The cutting machine involved in this embodiment can realize accurate positioning and cutting of the graphite cylinder, effectively improve the cutting efficiency of the graphite cylinder, and the cut graphite tiles are uniform in size, thereby improving product quality.

Claims

1. A production process of graphite tiles for electrolytic rare earth, characterized in that: The following steps are involved: S1. Select raw materials, weigh graphitized thermal insulation materials of different finenesses, including 10-16 parts of large materials with a fineness of 3-6mm, 23-30 parts of medium materials with a fineness of 2-3mm, 32-38 parts of small materials with a fineness of 1-2mm, and 20-26 parts of powder materials with a fineness of 0.075-1mm, by weight, and mix the raw materials evenly to obtain a primary mixture; weigh 22-31 parts of reformed liquid asphalt and 69-78 parts of the primary mixture by weight, and mix the reformed liquid asphalt and the primary mixture for a second time to obtain a secondary mixture; S2, pouring the secondary mixture into a concave mold for heating and pressing to obtain a crucible-shaped graphite semi-finished product; S3, cutting the bottom of the crucible-shaped semi-finished product to obtain a graphite cylinder (1), and then using a cutting machine to cut the graphite cylinder (1) into 1 / 4 cylinder graphite tiles (2).

2. The production process of graphite tiles for electrolytic rare earth according to claim 1, characterized in that: In the step S1, the graphitized thermal insulation material, calculated by mass, includes 14 parts of large materials with a fineness of 3-6mm, 28 parts of medium materials with a fineness of 2-3mm, 35 parts of small materials with a fineness of 1-2mm, and 23 parts of powder materials with a fineness of 0.075-1mm; calculated by mass, 25 parts of reformed liquid asphalt and 75 parts of primary mixture are weighed, and the reformed liquid asphalt and the primary mixture are mixed for a second time to obtain a secondary mixture.

3. The production process of graphite tiles for electrolytic rare earth according to claim 1, characterized in that: In step S1, the large material, medium material, small material and powder material are all ball-milled powders.

4. The production process of graphite tiles for electrolytic rare earth according to claim 1, characterized in that: The cutting machine comprises a guide positioning component, a four-wire saw component and a clamping component for clamping a graphite cylinder (1); the positioning point on the guide positioning component is arranged in contact with the side wall of the graphite cylinder (1) to form a positioning ring (3); the four-wire saw component comprises a first saw rope (4) and a second saw rope (5) arranged in a cross shape and a driving unit respectively connected to the first saw rope (4) and the second saw rope (5); the clamping component and the four-wire saw component have the freedom of relative movement along the axial direction of the positioning ring (3); the clamping component is respectively arranged between the first saw rope (4) and the second saw rope (5) along the circumferential direction of the positioning ring (3); and the axis of the positioning ring (3) passes through the first saw rope (4) and the second saw rope (5) respectively.

5. The production process of graphite tiles for electrolytic rare earth according to claim 4, characterized in that: The guide positioning assembly comprises a fixed shaft (7) with a group of first hinged rods (6) thereon, and a sliding sleeve (9) sleeved on the fixed shaft (7) and with a second hinged rod (8), the first hinged rod (6) and the second hinged rod (8) being hinged to each other, the end of the first hinged rod (6) or the second hinged rod (8) extending outward from the hinge point and the positioning point being located at the end so as to fit with the inner wall of the graphite cylinder (1).

6. The production process of graphite tiles for electrolytic rare earth according to claim 5, characterized in that: The end of the second hinged rod (8) extends outward from the hinge point. A rotating wheel (10) is provided at the end of the second hinged rod (8). The rotating wheel (10) fits with the inner wall of the graphite cylinder (1) to form a positioning point.

7. The production process of graphite tiles for electrolytic rare earth according to claim 4, characterized in that: The clamping assembly comprises a main axial slide rail (11), a radial slide rail (12) arranged on the main axial slide rail (11), a secondary axial slide rail (13) and clamping plates (14) respectively located at both ends of the graphite cylinder (1), wherein the clamping plates (14) are respectively arranged on the secondary axial slide rails (13), and the clamping plates (14) respectively have the freedom to move radially toward the graphite cylinder (1) along the positioning ring (3) with the help of the radial slide rails (12), and the clamping plates (14) have the freedom to move axially along the positioning ring (3) with the help of the secondary axial slide rails (13).

8. The production process of graphite tiles for electrolytic rare earth according to claim 5, characterized in that: A fixing seat (16) with a guide slide hole is fixedly connected to the guide positioning component, and a guide slide block (15) matching the guide slide hole is fixedly connected to the first saw rope (4) and the second saw rope (5).

Images