A sealing structure and method for anode lead column and anode cover plate of fluorine production electrolytic cell

Abstract

The present invention provides a sealing structure and method for an anode lead post and an anode cover plate of a fluorine production electrolytic cell, comprising a lead post body, a sealing box integrally formed with the anode cover plate is sleeved on the outside of the lead post body, a steel sleeve is sleeved on the outside of the lead post body below the sealing box, an isolation pad is provided between the steel sleeve and the sealing box, and a granular insulating material layer, a flexible insulating material layer and a plurality of rigid insulating material layers are provided inside the sealing box. The sealing structure between the sealing box and the lead post body adopts the method of simultaneously providing a granular insulating material layer, a flexible insulating material layer and a plurality of rigid insulating material layers, and the granular material of the granular insulating material layer can be adaptively adjusted according to the vibration and pressure fluctuation of the electrolytic cell, so as to ensure that the insulation and sealing of the sealing box are not damaged under the vibration and pressure fluctuation conditions of the electrolytic cell, and the flexible insulating material layer has a certain toughness, further ensuring the sealing.

Description

Technical Field

[0001] The invention relates to the technical field of sealing of an anode wire column and an anode cover plate of a fluorine-producing electrolytic cell, and in particular to a sealing structure and method of an anode wire column and an anode cover plate of a fluorine-producing electrolytic cell. Background Art

[0002] The uranium purification and conversion electrolytic fluorine production line mainly uses 10kA carbon steel fluorine electrolytic cells as fluorine production equipment, and adopts the medium-temperature electrolytic fluorine production process commonly used at home and abroad to prepare fluorine gas. Through continuous exploration and optimization in recent years, the medium-temperature electrolytic fluorine production technology has achieved certain results, and the fluorine production capacity of the production line has met the needs of uranium purification and conversion. However, during the operation of the electrolytic fluorine production system, there are still problems such as frequent abnormal working conditions, such as: the wire column catches fire, which affects the continuity and stability of the fluorine supply system. The function of the wire column is to connect and fix the fluorine-making carbon plate in the electrolytic cell, and the wire column is connected to the power supply for electrolysis. During the assembly process of the electrolytic cell, the sealing and insulation of the wire column sealing box are extremely high. The insulation and sealing of the sealing box of the electrolytic cell are easily damaged under vibration and pressure fluctuation conditions. When the sealing of the wire column sealing box is damaged, air enters the electrolytic cell, oxygen reacts with fluorine gas, causing polytetrafluoroethylene to catch fire, which will cause a large amount of fluorine gas to leak. Summary of the invention

[0003] The purpose of the present invention is to provide a sealing structure and method for the anode wire column and the anode cover plate of a fluorine-producing electrolytic cell, wherein a granular insulating material layer, a flexible insulating material layer and a rigid insulating material layer are combined to fill and assemble the sealed box, thereby improving the insulation and sealing of the sealed box, thereby reducing or eliminating the fire failure of the wire column.

[0004] The technical solution of the present invention provides a sealing structure of an anode wire column and an anode cover plate of a fluorine-producing electrolytic cell, comprising a wire column body, a sealing box integrally formed with the anode cover plate is sleeved on the outer side of the wire column body, a steel sleeve is sleeved on the outer side of the wire column body below the sealing box, an isolation pad is provided between the steel sleeve and the sealing box, and a granular insulating material layer, a flexible insulating material layer and multiple rigid insulating material layers are provided inside the sealing box.

[0005] Furthermore, the granular insulating material layer includes a calcium fluoride powder layer and a polytetrafluoroethylene powder layer, the flexible insulating material layer is sealing mud, and the rigid insulating material layer is a polytetrafluoroethylene pad, a bakelite pad or a steel gasket.

[0006] Furthermore, the interior of the sealing box is sequentially provided with sealing mud, a first polytetrafluoroethylene pad, a first polytetrafluoroethylene powder layer, a calcium fluoride powder layer, a second polytetrafluoroethylene powder layer, a second polytetrafluoroethylene pad, a bakelite pad and a steel pad from bottom to top.

[0007] Furthermore, the components of the sealing mud include epoxy resin, maleic acid and phthalate.

[0008] Furthermore, the components of the sealing mud are calculated by weight: 55-65 parts of epoxy resin, 10-20 parts of maleic acid, and 25 parts of phthalate.

[0009] Furthermore, the components of the sealing mud are calculated by weight: 60 parts of epoxy resin, 15 parts of maleic acid, and 25 parts of phthalate.

[0010] Furthermore, the isolation pad is made of polytetrafluoroethylene material, and is a boss-shaped structure, and the top end of the isolation pad abuts against the bottom end of the sealing mud.

[0011] Furthermore, a compression nut is installed on the top of the steel pad on the conductor column body.

[0012] A sealing method for an anode lead column and an anode cover plate of a fluorine-producing electrolytic cell is implemented based on a sealing structure of the anode lead column and the anode cover plate of the fluorine-producing electrolytic cell, and specifically comprises the following steps:

[0013] S1: Filter the calcium fluoride powder, place it in an oven, dry it at 100℃-120℃ for 24 hours, take it out, and put it at room temperature for use;

[0014] S2: Sealing mud is mixed with calcium fluoride powder in a ratio of 60 parts of epoxy resin, 15 parts of maleic acid and 25 parts of phthalate;

[0015] S3: Roll the sealing mud into a round strip of φ12mm-16mm and coil it around the bottom of the sealing box. Install the first polytetrafluoroethylene pad and press the sealing mud downward to make it flat. Then lay the first polytetrafluoroethylene powder layer, calcium fluoride powder layer, second polytetrafluoroethylene powder layer, second polytetrafluoroethylene pad, bakelite pad and steel pad in sequence.

[0016] Furthermore, in step S1, the calcium fluoride powder is filtered using a 120-mesh sieve.

[0017] The technical solution of the present invention has the following beneficial effects over the prior art: the sealing structure between the sealing box and the conductor column body adopts a granular insulating material layer, a flexible insulating material layer and multiple rigid insulating material layers, and the granular material of the granular insulating material layer can be adaptively adjusted according to the vibration and pressure fluctuations of the electrolytic cell, ensuring that the insulation and sealing of the sealing box are not damaged under the vibration and pressure fluctuation conditions of the electrolytic cell, and the flexible insulating material layer has a certain toughness to further ensure the sealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a schematic diagram of the connection between the conductor column body and the fluorocarbon plate in the present invention;

[0020] Figure 2 A cross-sectional view of the sealing structure between the conductor post and the anode cover plate in the present invention;

[0021] Explanation of the accompanying drawings: 1-conductor column body, 2-steel sleeve, 3-sealing box, 4-isolating pad, 5-sealing mud, 6-first polytetrafluoroethylene pad, 7-first polytetrafluoroethylene powder layer, 8-calcium fluoride powder layer, 9-second polytetrafluoroethylene powder layer, 10-second polytetrafluoroethylene pad, 11-bakelite pad, 12-steel pad, 13-tightening nut, 14-anode cover. DETAILED DESCRIPTION

[0022] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0024] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] Example 1

[0026] like Figure 1 and Figure 2 As shown, a sealing structure of an anode wire column and an anode cover plate of a fluorine-producing electrolytic cell includes a wire column body 1, a sealing box 3 integrally formed with the anode cover plate 14 is sleeved on the outer side of the wire column body 1, a steel sleeve 2 is sleeved on the outer side of the wire column body 1 below the sealing box 3, and the steel sleeve 2 is screwed and connected to the wire column body 1 to form a support for the sealing box 3 at its top.

[0027] In order to ensure that the insulation and sealing properties of the sealing box 3 are not damaged under the conditions of electrolytic cell vibration and pressure fluctuation, a granular insulating material layer, a flexible insulating material layer and a plurality of rigid insulating material layers are arranged inside the sealing box 3. The granular insulating material layer includes a calcium fluoride powder layer 8 and a polytetrafluoroethylene powder layer, the flexible insulating material layer is a sealing mud 5, and the rigid insulating material layer is a polytetrafluoroethylene pad, a bakelite pad 11 or a steel gasket. When sealing, the sealing mud 5, the first polytetrafluoroethylene pad 6, the first polytetrafluoroethylene powder layer 7, the calcium fluoride powder layer 8, the second polytetrafluoroethylene powder layer 9, the second polytetrafluoroethylene pad 10, the bakelite pad 11 and the steel pad 12 are arranged in sequence from bottom to top inside the sealing box 3. A compression nut 13 is installed on the top of the steel pad 12 on the conductor body 1, which is used to compress the various sealing layers inside the sealing box 3, especially to make the granular insulating material layer more compact; the reason why calcium fluoride powder is laid over a large area inside the sealing box 3 is that: on the one hand, the calcium fluoride powder plays an insulating role and does not react with fluorine gas; on the other hand, the calcium fluoride powder particles will not adhere when heated, which facilitates the later disassembly of the sealing box 3; the bakelite pad 11 plays an insulating role.

[0028] An isolation pad 4 made of polytetrafluoroethylene material and having an isolation and sealing effect is arranged between the steel sleeve 2 and the sealing box 3. The isolation pad 4 is a boss-shaped structure, and the top end of the isolation pad 4 abuts against the bottom end of the sealing mud 5.

[0029] Taking into full consideration that the chemical properties of fluorine gas are very active and its oxidizing property is extremely strong, in order to make the sealing mud 5 non-reactive with fluorine gas and have a certain toughness after curing at room temperature or the operating temperature of the electrolytic cell, the present invention adopts epoxy resin, maleic acid and phthalate to make the sealing material according to a certain ratio. Because epoxy resin has a strong cohesive force and a dense molecular structure, it is a beneficial and multifunctional electrical insulating material. After curing, epoxy resin has an excellent dielectric constant. Add suitable curing agent, toughening agent and solid filler, and self-curing at room temperature to 100°C, with good sealing and insulation. In addition, taking into full consideration that the chemical properties of fluorine gas are very active, in order to make the sealing mud 5 non-reactive with fluorine gas and have a certain toughness after curing at room temperature or the operating temperature of the electrolytic cell, maleic acid is used as a curing agent and phthalate is used as a toughening agent, thereby improving the shrinkage, strength and tolerance of the sealing mud 5. The present invention selects epoxy resin, and simultaneously adopts maleic acid as a curing agent and phthalate as a toughening agent.

[0030] The specific formula of epoxy resin, maleic acid and phthalate is as follows:

[0031] Formula 1: 65g epoxy resin, 10g maleic acid glycol, 25g phthalate;

[0032] Formula 2: 60g epoxy resin, 15g maleic acid glycol, 25g phthalate;

[0033] Formula 3: 55g epoxy resin, 20g maleic acid glycol, 25g phthalate;

[0034] According to the working condition operation verification, the sealing mud 5 made by the formula 2 of the present invention has better sealing, insulation and operating conditions than the formulas 1 and 3, and its specific characteristics are as follows: it can be fully cured at the operating temperature, and the hardness, flexibility and surface finish after curing meet the working condition requirements; the sealing mud 5 does not react with fluorine gas and hydrogen fluoride gas before and after curing; it becomes a ceramic-like substance after curing and adheres to the metal at the sealing part, with good sealing effect, and no fluorine gas leakage incident occurs in the sealing box 3 during the operation cycle of the electrolytic cell; the dielectric property is good, the resistivity is greater than 107ΩΩm, and the resistivity of the formulas 1 and 3 are both less than 100ΩΩm.

[0035] A sealing method for an anode lead column and an anode cover plate of a fluorine production electrolytic cell, the sealing method comprising the following steps: firstly, using a 120-mesh screen to filter calcium fluoride powder to make the particles of the calcium fluoride powder smaller, thereby making the gaps between the calcium fluoride powder particles smaller and having good sealing performance, and then placing the calcium fluoride powder in an oven, drying it at 100°C-120°C for 24 hours, taking it out, and placing it at room temperature for standby use; then, sealing mud 5 is prepared according to the mixture of 60 parts of epoxy resin, 15 parts of maleic acid and 25 parts of phthalate. After mixing in proportion, stir and mix with calcium fluoride powder; roll the sealing mud 5 into a round strip of φ12mm-16mm and coil it around the bottom end of the sealing box 3, install the first polytetrafluoroethylene pad 6 to press the sealing mud 5 downward to make the sealing mud 5 flat, and then lay the first polytetrafluoroethylene powder layer 7, calcium fluoride powder layer 8, second polytetrafluoroethylene powder layer 9, second polytetrafluoroethylene pad 10, bakelite pad 11 and steel pad 12 in sequence, and finally use the clamping nut 13 to tighten the steel pad 12.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A sealing structure for an anode lead column and an anode cover plate of a fluorine production electrolytic cell, characterized in that: It comprises a conductor post body, the outer side of which is sleeved with a sealing box integrally formed with the anode cover plate, a steel sleeve is sleeved with the outer side of the conductor post body below the sealing box, an isolation pad is arranged between the steel sleeve and the sealing box, and the interior of the sealing box is arranged with sealing mud, a first polytetrafluoroethylene pad, a first polytetrafluoroethylene powder layer, a calcium fluoride powder layer, a second polytetrafluoroethylene powder layer, a second polytetrafluoroethylene pad, a bakelite pad and a steel pad in sequence from bottom to top.

2. The sealing structure of the anode lead column and the anode cover plate of the fluorine production electrolytic cell according to claim 1, characterized in that: The components of the sealing mud include epoxy resin, maleic acid and phthalic acid ester.

3. The sealing structure of the anode lead column and the anode cover plate of the fluorine production electrolytic cell according to claim 2, characterized in that: The components of the sealing mud are calculated by weight: 55-65 parts of epoxy resin, 10-20 parts of maleic acid, and 25 parts of phthalate.

4. The sealing structure of the anode lead column and the anode cover plate of the fluorine production electrolytic cell according to claim 1, characterized in that: The isolation pad is made of polytetrafluoroethylene material and is a boss-shaped structure. The top end of the isolation pad abuts against the bottom end of the sealing mud.

5. The sealing structure of the anode lead column and the anode cover plate of the fluorine production electrolytic cell according to claim 1, characterized in that: A compression nut is installed on the top of the steel pad on the conductor column body.

6. A method for sealing the anode lead column and the anode cover plate of a fluorine production electrolytic cell, characterized in that: The sealing structure of the anode lead column and the anode cover plate of the fluorine production electrolytic cell according to any one of claims 1 to 5 is realized, and specifically comprises the following steps: S1: Filter the calcium fluoride powder, place it in an oven, dry it at 100℃-120℃ for 24 hours, take it out, and put it at room temperature for use; S2: Sealing mud is mixed with calcium fluoride powder in a ratio of 55-65 parts of epoxy resin, 10-20 parts of maleic acid and 25 parts of phthalate; S3: Roll the sealing mud into a round strip of φ12mm-16mm and coil it around the bottom of the sealing box. Install the first polytetrafluoroethylene pad and press the sealing mud downward to make it flat. Then lay the first polytetrafluoroethylene powder layer, calcium fluoride powder layer, second polytetrafluoroethylene powder layer, second polytetrafluoroethylene pad, bakelite pad and steel pad in sequence.

7. The sealing method for the anode lead column and the anode cover plate of the fluorine production electrolytic cell according to claim 6, characterized in that: In step S1, the calcium fluoride powder is filtered using a 120-mesh sieve.

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