Flue gas collecting device for crust breaking hammer rod of electrolytic cell

Abstract

The utility model discloses a flue gas collecting device for a crust breaking hammer rod of an electrolytic cell, which comprises a fixed sealing cover and a telescopic sealing cover, the fixed sealing cover is butted with a truss of the electrolytic cell, the telescopic sealing cover is hermetically mounted on the fixed sealing cover, and the telescopic sealing cover and the fixed sealing cover together cover the crust breaking hammer rod inside; a sealing cover is arranged at the top of the telescopic sealing cover and connected with the upper portion of the crust breaking hammer rod so that the telescopic sealing cover can stretch out and draw back vertically along with vertical movement of the crust breaking hammer rod. The top end of the crust breaking hammer rod is connected with a cylinder rod of the crust breaking air cylinder, and the fixed sealing cover is connected with an external smoke pipe mechanism. In this way, it can be guaranteed that the crust breaking hammer rod is covered with the sealing cover all the time, and therefore the problems that an original crust breaking hammer rod sealing structure is short in service life, inconvenient to maintain and prone to causing smoke overflow to pollute the environment can be solved. And meanwhile, flue gas can be actively collected in the whole process, and the problem of flue gas leakage at the hammer rod of the electrolytic cell is fundamentally solved.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas treatment, in particular to a flue gas collecting device mainly for a shelling hammer rod of an electrolytic cell. Background Art

[0002] During the electrolysis of cryolite-alumina molten salt, aluminum is precipitated on the cathode, and a large amount of CO, CO2 and some fluorides are generated on the anode. Since alumina contains 0.2-0.5% moisture and atmospheric water vapor, solid fluoride salt reacts under high temperature (400-600°C) to generate HF gas. The chemical formula is as follows:

[0003] 2Na3ALF6+3H2O=2AL2O3+6NaF+6HF↑

[0004] 2ALF3+3H2O=AL2O3+6HF↑

[0005] At the same time, since both alumina powder and fluoride salts have certain dissipative properties, the main components of electrolytic flue gas are CO, CO2, some fluorides and HF gas. If it is not collected in time and allowed to diffuse in the electrolytic plant or diffuse into the atmosphere, it will have great harm to the physical and mental health of workers and the surrounding ecological environment. Therefore, aluminum electrolysis is equipped with a special collection system for electrolytic flue gas at the beginning of its design. The flue gas collected by the electrolytic cell gas hood is the primary flue gas, and the flue gas that enters the air of the electrolytic plant without being collected by the gas hood is called secondary flue gas. The volume of primary flue gas is small, and the concentration of fluoride is relatively large. After being collected by the electrolytic cell gas hood, it enters the purification system and is discharged into the atmosphere after being purified by alumina powder dry method; the volume of secondary flue gas is large, and the concentration of fluoride is small. It is mainly discharged into the atmosphere naturally through the skylight of the plant. Therefore, the collection of primary flue gas by the electrolytic cell gas hood is very important for the collection and purification of electrolytic flue gas, and the collection rate is required to be above 98%.

[0006] The efficiency of flue gas collection in the electrolytic cell is not only related to the negative pressure of the smoke exhaust fan, but also to the sealing of the electrolytic cell itself. According to the design and production practice of the electrolytic cell, there are three main aspects of electrolytic cell sealing: cell cover seal, anode guide rod seal, and shell hammer rod seal. The quality of these three seals directly affects the gas collection efficiency of the electrolytic cell. Among them, the shell hammer rod seal is mainly used for the seal between the shell hammer rod and the electrolytic cell rack. Due to its sealing maintenance space position, dynamic sealing and other characteristics, it is the most difficult to improve the sealing effect. At present, the widely used sealing methods are insulating brick sealing, "U"-shaped sealing of waste conveyor belts, etc., but the sealing effect is always poor. There are also problems such as the high cost of insulating bricks and the easy brittleness of conveyor belts under high-temperature baking.

[0007] The above problems are mainly reflected in the following aspects:

[0008] 1. The U-shaped insulating brick plus the sealing frame sealing method has basically good use effect. However, since the electrolysis personnel need to repeatedly hit the hammer rod when handling the shell head package and alumina accumulation, the U-shaped insulating brick is seriously damaged, and the cost of the insulating material U-shaped brick is high, which increases the maintenance cost.

[0009] 2. The "U"-shaped sealing method made of waste conveyor belts is easy to harden under high-temperature baking above 920°C in the electrolytic cell, and the material has a short service life.

[0010] 3. Both of the above methods have the problems of short service life and frequent replacement and maintenance of sealing materials. Since the internal frame space of the electrolytic cell rack is small, it is difficult for personnel to maintain, which increases the labor intensity of workers.

[0011] 4. The lack of seal of the shell hammer rod will affect the gas collection efficiency of the electrolytic cell, resulting in a worsening of the electrolytic plant environment and a low recovery rate of purified fluoride salts. In order to improve the gas collection efficiency of the electrolytic cell, the load of the smoke exhaust fan has to be increased, resulting in an increase in the electricity consumption cost of electrolytic production. Utility Model Content

[0012] The technical problem to be solved by the utility model is to provide a fume collection device for the shelling hammer rod of an electrolytic cell, which has a simple structure, better sealing effect, can realize separate and centralized recovery of fume at the shelling hammer rod, improve the fume recovery efficiency, and extend the life of the sealing material, in view of the shortcomings of the prior art.

[0013] In order to solve the above technical problems, the utility model adopts the following technical scheme: a fume collection device for the shelling hammer rod of the electrolytic cell, characterized in that: it includes a fixed sealing cover and a telescopic sealing cover, the fixed sealing cover is connected to the electrolytic cell frame, the telescopic sealing cover is sealingly installed on the fixed sealing cover, and together with the fixed sealing cover, the shelling hammer rod is covered inside; a sealing cover is arranged on the top of the telescopic sealing cover, the sealing cover is connected and fixed to the upper part of the shelling hammer rod so that the telescopic sealing cover forms a structure that can be telescoped up and down as the shelling hammer rod moves up and down; the top end of the shelling hammer rod is connected to the cylinder rod of the shelling cylinder, and a full-process sealing structure for the shelling hammer rod when working is formed through the cooperation of the sealing cover, the telescopic sealing cover and the fixed sealing cover with the electrolytic cell frame, and the fixed sealing cover is connected to an external smoke pipe mechanism.

[0014] Furthermore, a fixing plate is arranged near the upper end of the shell beating hammer rod, the fixing plate and the shell beating hammer rod are sealed and connected, and the sealing cover is sealed and fixed to the fixing plate.

[0015] Furthermore, a sealing insulating member is provided between the lower end of the fixed sealing cover and the electrolytic cell rack, and a sealing structure between the fixed sealing cover and the electrolytic cell rack is formed by the sealing insulating member.

[0016] Furthermore, the smoke pipe mechanism is connected outwardly and upwardly inclined from the lower side wall of the fixed sealing cover.

[0017] Preferably, the telescopic sealing cover is a cylindrical structure or a conical structure, and the upper diameter of the telescopic sealing cover with a conical structure is smaller than the lower diameter.

[0018] Preferably, a quick connection structure is adopted between the telescopic sealing cover and the fixed sealing cover.

[0019] Furthermore, the smoke pipe mechanism includes an oblique smoke pipe and a horizontal smoke pipe. The oblique smoke pipe is connected to the interior of the fixed sealing cover from the lower part of the side wall of the fixed sealing cover in an inclined posture, and the horizontal smoke pipe is connected to the top of the oblique smoke pipe in a horizontal posture; the horizontal smoke pipe is connected to a blower and connected to the electrolytic cell smoke pipe through the blower.

[0020] Furthermore, the horizontal smoke pipe and the blower are connected through a transition pipe, and the blower and the branch smoke pipe of the electrolytic cell are connected through a smoke outlet pipe. Insulating flanges are respectively provided on the transition pipe and the branch smoke pipe, and the insulating flanges form an insulation structure between the horizontal smoke pipe and the electrolytic cell and the blower.

[0021] Furthermore, the smoke collecting device of each shelling hammer rod is connected to an inclined smoke pipe, and each inclined smoke pipe is connected to the horizontal smoke pipe in an inclined posture.

[0022] Preferably, the inclination angle of the inclined smoke pipe is 30-60 degrees to ensure that alumina and fluorine-loaded alumina will not enter the horizontal smoke pipe during the smoke collection process of the inclined smoke pipe.

[0023] The utility model can move with the movement of the shell hammer rod by designing a movable sealing structure (mainly a fixed sealing cover and a movable seal), ensuring that the shell hammer rod is always covered inside, thereby solving the problems of the original shell hammer rod sealing structure having a short service life, inconvenient maintenance, and easy smoke overflow and pollution of the environment. At the same time, it can realize active collection of smoke throughout the process, fundamentally solving the problem of smoke leakage at the hammer rod of the electrolytic cell; and there is no need to worry about the impact of knocking the hammer rod when manually handling the shell head bag or a large pile of materials, so that the service life of the sealing device is longer and the labor intensity of workers can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the utility model.

[0025] In the figure, 1 is a shelling hammer rod, 2 is an electrolytic cell frame, 3 is a shelling cylinder, 4 is a fixed plate, 5 is a fixed sealing cover, 6 is a telescopic sealing cover, 7 is a sealing cover, 8 is a sealing insulating member, 9 is an oblique smoke pipe, 10 is a horizontal smoke pipe, 11 is a transition pipe, 12 is a blower, 13 is a smoke outlet pipe, 14 is an insulating flange, and 15 is an electrolytic cell smoke support pipe. DETAILED DESCRIPTION

[0026] In this embodiment, refer to Figure 1 The fume collecting device for the shelling hammer rod of the electrolytic cell includes a fixed sealing cover 5 and a telescopic sealing cover 6. The fixed sealing cover 5 is docked with the electrolytic cell frame 2. The telescopic sealing cover 6 is sealed and installed on the fixed sealing cover 5. Together with the fixed sealing cover 5, the shelling hammer rod 1 is covered inside. The telescopic sealing cover 6 can be made of materials such as aluminum foil tubes similar to those of range hoods so that it can be freely extended and retracted within its length range. A sealing cover 7 is arranged on the top of the telescopic sealing cover 6. The sealing cover 7 is connected and fixed to the upper part of the shelling hammer rod 1 so that the telescopic sealing cover 6 can move up and down with the shelling hammer rod 1; the top end of the shelling hammer rod 1 is connected to the cylinder rod of the shelling cylinder 3, and the shelling hammer rod 1 is driven by the shelling cylinder 3 to move up and down. The shelling hammer rod 1 is fully sealed during operation through the cooperation of the sealing cover 7, the telescopic sealing cover 6 and the fixed sealing cover 5 with the electrolytic cell frame 2. The fixed sealing cover 5 is connected to the external smoke pipe mechanism so that the smoke can be discharged.

[0027] A fixing plate 4 is provided near the upper end of the shell beating hammer rod 1, and the fixing plate 4 and the shell beating hammer rod 1 are sealed. The sealing cover 7 is sealed and fixed to the fixing plate 4, for example, by cooperating with a sealing ring and bolts to achieve a sealing connection.

[0028] A sealing insulating member 8 is provided between the lower end of the fixed sealing cover 5 and the electrolytic cell frame 2 , and a sealing structure between the fixed sealing cover 5 and the electrolytic cell frame 2 is formed by the sealing insulating member 8 .

[0029] The smoke pipe mechanism is connected outwardly and upwardly inclined from the lower side wall of the fixed sealing cover 5.

[0030] The telescopic sealing cover 6 is a cylindrical structure or a conical structure. The upper diameter of the telescopic sealing cover 6 with a conical structure is smaller than the lower diameter, which can reduce the space occupied by the telescopic sealing cover.

[0031] A quick connection structure is adopted between the telescopic sealing cover 6 and the fixed sealing cover 5 to improve the replacement and maintenance efficiency of the telescopic sealing cover.

[0032] The smoke pipe mechanism includes an oblique smoke pipe 9 and a horizontal smoke pipe 10. The oblique smoke pipe 9 is connected to the interior of the fixed sealing cover 5 from the lower part of the side wall of the fixed sealing cover 5 in an inclined posture, and the horizontal smoke pipe 10 is connected to the top of the oblique smoke pipe 9 in a horizontal posture; the horizontal smoke pipe 10 is connected to a blower 12, and is connected to the electrolytic cell smoke pipe 15 through the blower 12.

[0033] The horizontal smoke duct 10 and the blower 12 are connected via a transition duct 11, and the blower 12 and the electrolytic cell branch smoke duct 15 are connected via a smoke outlet pipe 13. Insulating flanges 14 are provided on the transition duct 11 and the branch smoke duct 13, respectively. The insulating flanges 14 form an insulating structure between the horizontal smoke duct 10 and the electrolytic cell and the blower 12 to prevent short circuit.

[0034] There may be multiple sets of shell beating hammer rod mechanisms, and the smoke collecting device of each shell beating hammer rod 1 is connected to an inclined smoke pipe 9, and each inclined smoke pipe 9 is connected to the horizontal smoke pipe 10 in the same inclined posture.

[0035] The inclination angle of the oblique smoke pipe 9 is 30-60 degrees, for example 37 degrees, to ensure that alumina and fluorine-carrying alumina will not enter the horizontal smoke pipe during the smoke collection process of the oblique smoke pipe.

[0036] When the shelling operation stops, the shelling cylinder 3 contracts, the shelling hammer rod 1 rises to the highest point, and the telescopic sealing cover 6 is stretched by the sealing cover 7, so that the entire sealing cover completely covers the shelling hammer rod 1, and the smoke overflowing between the shelling hammer rod 1 and the electrolytic cell rack 2 is all collected in the fixed sealing cover 5 and the telescopic sealing cover 6. Under the action of the blower 12, it enters the electrolytic cell branch smoke pipe 15 through the oblique smoke pipe 9, the horizontal smoke pipe 10, the filter pipe 11, and the smoke outlet pipe 13 to complete the collection; during the shelling operation, the telescopic sealing cover 6 is compressed by the sealing cover 7 and descends together with the shelling hammer rod 1, and the entire sealing cover still completely covers the shelling hammer rod 1, and the smoke is still all collected in the fixed sealing cover 5 and the telescopic sealing cover 6, and enters the electrolytic cell branch smoke pipe 15 through the oblique smoke pipe 9, the horizontal smoke pipe 10, the filter pipe 11, and the smoke outlet pipe 13 to complete the collection.

[0037] The present invention has been described in detail above. The above description is only a preferred embodiment of the present invention and should not limit the scope of implementation of the present invention. That is, all equivalent changes and modifications made within the scope of this application should still fall within the scope of the present invention.

Claims

1. A fume collection device for a shelling hammer rod of an electrolytic cell, characterized in that: It comprises a fixed sealing cover and a telescopic sealing cover, the fixed sealing cover is docked with the electrolytic cell rack, the telescopic sealing cover is sealingly installed on the fixed sealing cover, and together with the fixed sealing cover, covers the shell beating hammer rod inside; a sealing cover is arranged on the top of the telescopic sealing cover, the sealing cover is connected and fixed to the upper part of the shell beating hammer rod so that the telescopic sealing cover forms a structure that can be telescoped up and down as the shell beating hammer rod moves up and down; the top end of the shell beating hammer rod is connected to the cylinder rod of the shell beating cylinder, and a full-process sealing structure for the shell beating hammer rod when working is formed through the cooperation of the sealing cover, the telescopic sealing cover and the electrolytic cell rack, and the fixed sealing cover is connected to the external smoke pipe mechanism.

2. The fume collection device for the shelling hammer rod of the electrolytic cell according to claim 1 is characterized in that: A fixing plate is arranged near the upper end of the shell beating hammer rod, the fixing plate and the shell beating hammer rod are sealed and connected, and the sealing cover is sealed and fixed to the fixing plate.

3. The fume collection device for the shelling hammer rod of the electrolytic cell according to claim 1 is characterized in that: A sealing insulating member is arranged between the lower end of the fixed sealing cover and the electrolytic cell frame, and a sealing structure between the fixed sealing cover and the electrolytic cell frame is formed by the sealing insulating member.

4. The fume collection device for the shelling hammer rod of the electrolytic cell according to claim 1 is characterized in that: The smoke pipe mechanism is connected outwardly and upwardly inclined from the lower side wall of the fixed sealing cover.

5. The fume collection device for the shelling hammer rod of the electrolytic cell according to claim 1 is characterized in that: The telescopic sealing cover is a cylindrical structure or a conical structure. The upper diameter of the telescopic sealing cover with a conical structure is smaller than the lower diameter.

6. The fume collection device for the shelling hammer rod of the electrolytic cell according to claim 1 is characterized in that: A quick connection structure is adopted between the telescopic sealing cover and the fixed sealing cover.

7. The fume collection device for the shelling hammer rod of the electrolytic cell according to claim 1 or 4, characterized in that: The smoke pipe mechanism includes an oblique smoke pipe and a horizontal smoke pipe. The oblique smoke pipe is connected to the interior of the fixed sealing cover from the lower part of the side wall of the fixed sealing cover in an inclined posture, and the horizontal smoke pipe is connected to the top of the oblique smoke pipe in a horizontal posture; the horizontal smoke pipe is connected to a blower and connected to the electrolytic cell smoke pipe through the blower.

8. The fume collection device for the shelling hammer rod of the electrolytic cell according to claim 7 is characterized in that: The horizontal smoke pipe and the blower are connected through a transition pipe, and the blower and the branch smoke pipe of the electrolytic cell are connected through a smoke outlet pipe. Insulating flanges are respectively provided on the transition pipe and the branch smoke pipe to form an insulating structure between the horizontal smoke pipe and the electrolytic cell and the blower.

9. The fume collection device for the shelling hammer rod of the electrolytic cell according to claim 7 is characterized in that: The smoke collecting device of each shelling hammer rod is connected with an inclined smoke pipe, and each inclined smoke pipe is connected to the horizontal smoke pipe in an inclined posture.

10. The fume collection device for the shelling hammer rod of the electrolytic cell according to claim 9, characterized in that: The inclination angle of the oblique smoke pipe is 30-60 degrees.

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