Aluminum electrolysis multi-series flue gas desulfurization system

Abstract

This utility model relates to a multi-series flue gas desulfurization system for aluminum electrolysis. Each electrolysis series is equipped with 1-3 sets of fixed desulfurization devices, and all electrolysis series share one set of mobile desulfurization backup devices. Both the fixed and mobile backup devices are ultrafine droplet horizontal desulfurization devices. The shell of the ultrafine droplet horizontal desulfurization device is assembled from multiple modules, which are connected by bolts, and sealed at the joints. A chimney is provided outside the fixed desulfurization device. The tops of the shells of both the fixed and mobile backup devices are connected to the chimney via flue pipes. A desulfurization slurry tank and a support are located on the ground near the fixed desulfurization device, and the support is used to install the mobile backup device. This utility model requires only one set of mobile backup devices, which can be disassembled and reused, resulting in high utilization and significantly reduced investment costs. The elimination of the need for a chimney for the mobile backup device further saves costs.

Description

Technical Field

[0001] This utility model relates to a desulfurization system, and more particularly to a multi-series flue gas desulfurization system for aluminum electrolysis, belonging to the field of aluminum electrolysis flue gas desulfurization technology. Background Technology

[0002] With the increase in desulfurization facilities in electrolytic aluminum plants across the country, electrolytic desulfurization must not only achieve ultra-low emissions, but also minimize the energy consumption of the desulfurization system.

[0003] Currently, mature flue gas desulfurization technologies both domestically and internationally mainly include limestone-gypsum method, ammonia method, and circulating fluidized bed semi-dry desulfurization technology. In particular, the mature and widely used limestone-gypsum wet desulfurization technology occupies a dominant position in the treatment of electrolytic aluminum flue gas.

[0004] To address the issue of corrosion damage and detachment of the anti-corrosion lining in limestone-gypsum wet desulfurization towers, regular overhauls are essential, typically occurring every 2-4 weeks. During this maintenance period, the desulfurization tower cannot operate normally, therefore a backup system must be available to ensure continuity of service. During maintenance, sulfur dioxide emissions must adhere to a concentration not exceeding 35 mg / Nm³. 3 Environmental standards requirements.

[0005] Furthermore, aluminum electrolysis plants typically require multiple electrolysis series, necessitating the construction of multiple desulfurization systems, along with multiple backup desulfurization units and chimneys. However, each backup system operates for a short period annually and is used infrequently, resulting in high investment and maintenance costs. Therefore, it is necessary to develop a solution that addresses the backup issue of wet desulfurization units during maintenance periods while meeting stringent emission requirements and achieving energy conservation and emission reduction. Summary of the Invention

[0006] To address the above technical problems, this utility model provides a multi-series flue gas desulfurization system for aluminum electrolysis, aiming to achieve energy saving and consumption reduction, as well as solve the backup problem of the desulfurization device during maintenance.

[0007] To achieve the above objectives, this utility model is implemented as follows: A multi-series flue gas desulfurization system for aluminum electrolysis, wherein 1-3 sets of fixed desulfurization devices are set in each electrolysis series, and all electrolysis series share one set of mobile desulfurization backup device; wherein the fixed desulfurization device and the mobile desulfurization backup device are ultrafine droplet horizontal desulfurization devices, the shell of the ultrafine droplet horizontal desulfurization device is assembled from multiple modules, the different modules are connected by bolts, and a sealing element is set at the connection; a chimney is provided outside the fixed desulfurization device, and the top of the shell of the fixed desulfurization device and the mobile desulfurization backup device are respectively connected to the chimney through flue pipes; a desulfurization slurry tank and a support are provided on the ground near the fixed desulfurization device, and the support is used to install the mobile desulfurization backup device.

[0008] The bottom of the ultrafine droplet horizontal desulfurization device is connected to the desulfurization slurry tank through a first pipeline, and the lower part of the ultrafine droplet horizontal desulfurization device is connected to the desulfurization slurry tank through a second pipeline. The ultrafine droplet horizontal desulfurization device, the first pipeline, the second pipeline and the desulfurization slurry tank form a slurry circulation.

[0009] Valves are installed on the first and second pipelines.

[0010] A circulation pump is installed on the second pipeline.

[0011] The desulfurization slurry tank is connected to the slurry supply system.

[0012] When the ultrafine droplet horizontal desulfurization device is a mobile desulfurization backup device, the bottom of the mobile desulfurization backup device is provided with a second quick connector, which is connected to the first pipeline, and the lower part of the mobile desulfurization backup device is provided with a first quick connector, which is connected to the second pipeline.

[0013] The mobile desulfurization backup device is equipped with a third quick-connect fitting on its housing for quick connection with auxiliary equipment of the fixed desulfurization device. The third quick-connect fitting is connected to the flue gas duct, process water system and oxidation air system through pipes and quick-connect fittings respectively.

[0014] The bracket and the bracket connecting bolts are connected, and the top of the bracket is bolted to the bottom of the mobile desulfurization backup device housing; the housing of the fixed desulfurization device and the mobile desulfurization backup device are detachable in 2-3 layers along the height direction, and each layer of housing is divided into 2 to 10 detachable modules along the length direction; the modules are connected by bolts, and a seal is set at the connection.

[0015] Each module of the housing of the fixed desulfurization device and the mobile desulfurization backup device has an edge at the connection point, and the two edges are fixed by bolts, with a seal between the two edges.

[0016] The housing is made of stainless steel corrosion-resistant material of grade 2205 or 316L.

[0017] Advantages and effects of this utility model:

[0018] This novel device employs an ultra-fine droplet horizontal desulfurization unit, which features low system resistance, low liquid-to-gas ratio, and low system energy consumption, achieving energy saving and consumption reduction in the desulfurization and purification of aluminum electrolysis flue gas.

[0019] The mobile desulfurization backup device of this utility model can be disassembled and moved to the ground near the fixed desulfurization device that needs to be repaired for installation. Therefore, only one set needs to be configured, which can be repeatedly disassembled and used among multiple fixed desulfurization systems in multiple electrolysis series. The device has a high utilization rate and significantly reduces investment costs.

[0020] Both the stationary desulfurization unit and the mobile desulfurization backup unit are made of corrosion-resistant materials, making maintenance and repair convenient.

[0021] This utility model of a mobile desulfurization backup device eliminates the need for a chimney. When needed, the mobile desulfurization backup device is connected to the chimney of the fixed desulfurization device via a flue pipe. Since the chimney can reach a height of 60-80 meters, the flue gas from the mobile desulfurization backup device is connected to the chimney of the fixed desulfurization device via a flue pipe. This eliminates the need to configure a chimney for the mobile desulfurization backup device, greatly saving costs.

[0022] The fixed desulfurization device and the mobile desulfurization backup device in this utility model are both modularly installed, which is convenient for disassembly and assembly, has a short construction period, requires less high-altitude work, and is suitable for the high magnetic field environment of aluminum electrolysis. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of this utility model.

[0024] Figure 2 This is a schematic diagram of the installation structure of a mobile desulfurization backup device.

[0025] In the diagram: 1. Chimney; 2. Mobile desulfurization backup unit; 3. Fixed desulfurization unit; 4. Desulfurization slurry tank; 5. Slurry supply system; 6. Flue gas pipeline; 7. Process water system; 8. Oxidation air system; 9. Circulating pump system; 10. First quick-connect coupling; 11. Second quick-connect coupling; 12. Desulfurization unit shell; 13. Module; 14. Flue pipe; 15. Support; 16. Support connecting bolts; 17. Ground; 18. First pipeline; 19. Second pipeline; 20. Third quick-connect coupling. Detailed Implementation

[0026] The specific embodiments of this utility model will now be explained in detail and clearly with reference to the accompanying drawings. It should be noted that the presented embodiments represent only a part of the many possible embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are also subject to the protection of this utility model patent.

[0027] like Figure 1As shown, this utility model discloses a multi-series flue gas desulfurization system for aluminum electrolysis. Each electrolysis series is equipped with 1-3 sets of fixed desulfurization devices 3. In this embodiment, there are 2 sets of fixed desulfurization devices 3, and all electrolysis series share one set of mobile desulfurization backup device 2. The fixed desulfurization devices 3 and the mobile backup device 2 are ultrafine droplet horizontal desulfurization devices. The shell of the ultrafine droplet horizontal desulfurization device is assembled from multiple modules 13, which are connected by bolts, and sealed at the connection points. A chimney 1 is provided between the two sets of fixed desulfurization devices 3. The tops of the shells 12 of the fixed desulfurization devices 3 and the mobile backup device 2 are respectively connected to the chimney 1 via flue pipes 14. A desulfurization slurry tank 4 and a support 15 are provided on the ground near the fixed desulfurization devices 3. The support 15 is used to install the mobile backup device 2. The bottom of the ultrafine droplet horizontal desulfurization device is connected to the desulfurization slurry tank 4 via a first pipeline 18, and the lower part of the ultrafine droplet horizontal desulfurization device is connected to the desulfurization slurry tank 4 via a second pipeline 19. The ultrafine droplet horizontal desulfurization device, the first pipeline 18, the second pipeline 19, and the desulfurization slurry tank 4 form a slurry circulation system. Valves are installed on the first pipeline 18 and the second pipeline 19. A circulation pump 9 is installed on the second pipeline 19. The desulfurization slurry tank 4 is connected to the slurry supply system 5.

[0028] The mobile desulfurization backup device 2 is equipped with a second quick-connect fitting 11 at its bottom, which is connected to the first pipeline 18. The mobile desulfurization backup device 2 is also equipped with a first quick-connect fitting 10 at its lower part, which is connected to the second pipeline 19. The pipeline transport length between the first quick-connect fitting 10 and the second quick-connect fitting 11 and the desulfurization slurry tank 4 should be minimized.

[0029] The mobile desulfurization backup device 2 is equipped with multiple third quick-connect joints 20 that can be quickly connected to the auxiliary equipment of the fixed desulfurization device 3. The third quick-connect joints 20 are connected to the flue gas pipeline 6, the process water system 7 and the oxidation air system 8 through pipes and quick-connect joints respectively.

[0030] The bracket 15 and bracket connecting bolts 16 are connected to support the mobile desulfurization unit 2 and maintain its stability. The top of the bracket 15 is bolted to the bottom of the mobile desulfurization backup unit housing 12; the housings of the fixed desulfurization unit 3 and the mobile desulfurization backup unit 2 are detachable in 2-3 layers along the height direction, and each layer of housing is divided into 2 to 10 detachable modules 13 along the length direction; the modules 13 are bolted together and sealed at the connection.

[0031] Each module 13 of the housing of the fixed desulfurization device 3 and the mobile desulfurization backup device 2 has an edge at the connection point, and the two edges are fixed by bolts, with a seal between the two edges.

[0032] The housing 12 is made of stainless steel corrosion-resistant material of grade 2205 or 316L.

[0033] In this embodiment, the fixed desulfurization unit 3 and the mobile desulfurization backup unit 2 have external dimensions of 18m (length), 5m (width), and 6m (height). For ease of transportation and installation, a modular structure is adopted. The housing of both the fixed and mobile desulfurization backup units is divided into six sections: three along the length and two along the height. The fixed desulfurization unit remains stationary after installation. The mobile desulfurization backup unit... Figure 2 The modules are connected by bolts and are installed on a support frame. The support frame is bolted to the ground foundation (17 meters) for easy disassembly and relocation to other purification systems. The system is 18 meters long and can utilize multiple support frames.

[0034] During construction, this utility model first requires the construction of multiple sets of fixed desulfurization units for various electrolysis series, including a desulfurization slurry tank 4, a slurry supply system 5, a flue gas pipeline 6, a process water system 7, an oxidation air system 8, and a circulating pump 9. Each of the flue gas pipeline 6, process water system 7, oxidation air system 8, and circulating pump 9 is equipped with valves and quick-connect couplings. During installation, the fixed desulfurization units are hoisted, and different modules are connected by bolts with seals at the joints, then fixed to the ground. In this embodiment, a chimney is installed between two sets of fixed desulfurization units. The fixed desulfurization units remain operational during the aluminum electrolysis process. When a fixed desulfurization unit experiences problems such as damage or detachment of its anti-corrosion lining requiring repair, a mobile desulfurization backup unit can be transported nearby for assembly and use. During the assembly of the mobile desulfurization standby unit, the bracket 15 and bracket connecting bolts 16 are connected first. The various modules 13 of the housing 12 are then assembled on the top of the bracket 15 using bolt connections, with seals installed at the joints. Simultaneously, the internal components of the mobile desulfurization standby unit are installed. After assembly, the top of the mobile desulfurization standby unit's housing is connected to the chimney 1 of the fixed desulfurization unit via a flue pipe 14, allowing them to share a single chimney. The flue gas pipeline 6, process water system 7, oxidation air system 8, and circulating pump system 9 of the mobile desulfurization standby unit are connected to the mobile desulfurization standby unit via a first quick-connect connector 20. The pipeline is connected to the desulfurization slurry tank 4 via a second quick-connect connector 11. The fixed desulfurization unit is shut down, and the valves on the pipelines connecting to the first quick-connect connector 10 and the second quick-connect connector 11 are opened to allow the mobile desulfurization standby unit to operate and perform flue gas desulfurization.

[0035] After the stationary desulfurization unit is overhauled, the mobile desulfurization standby unit is disassembled from the ground foundation and transported to the vicinity of other stationary desulfurization units that need overhaul, where it is installed on the ground foundation.

[0036] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An aluminum electrolytic multi-train flue gas desulfurization system, characterized in that: 1-3 sets of fixed desulfurization devices (3) are set in each electrolysis series, and all electrolysis series share a set of mobile desulfurization backup devices (2); among them, the fixed desulfurization device (3) and the mobile desulfurization backup device (2) are ultra-fine droplet horizontal desulfurization devices. The shell of the ultra-fine droplet horizontal desulfurization device is assembled from multiple modules (13). The different modules (13) are connected by bolts, and a seal is set at the connection. A chimney (1) is set outside the fixed desulfurization device (3). The top of the shells of the fixed desulfurization device (3) and the mobile desulfurization backup device (2) are connected to the chimney (1) through the flue pipe (14). A desulfurization slurry tank (4) and a support (15) are set on the ground near the fixed desulfurization device (3). The support (15) is used to install the mobile desulfurization backup device (2).

2. The aluminum electrolysis multi-series flue gas desulfurization system according to claim 1, characterized in that: The bottom of the ultrafine droplet horizontal desulfurization device is connected to the desulfurization slurry tank (4) through the first pipeline (18), and the lower part of the ultrafine droplet horizontal desulfurization device is connected to the desulfurization slurry tank (4) through the second pipeline (19). The ultrafine droplet horizontal desulfurization device, the first pipeline (18), the second pipeline (19) and the desulfurization slurry tank (4) form a slurry circulation.

3. The aluminum electrolytic multi-stage flue gas desulfurization system according to claim 2, characterized in that: Valves are provided on the first pipeline (18) and the second pipeline (19).

4. The aluminum electrolysis multi-series flue gas desulfurization system according to claim 2 or 3, characterized in that: A circulation pump is installed on the second pipeline.

5. The aluminum electrolytic multi-stage flue gas desulfurization system according to claim 2, characterized in that: The desulfurization slurry tank (4) is connected to the slurry supply system (5).

6. The aluminum electrolysis multi-series flue gas desulfurization system according to claim 2, characterized in that: When the ultrafine droplet horizontal desulfurization device is a mobile desulfurization backup device (2), the mobile desulfurization backup device (2) is provided with a second quick connector (11) at the bottom, the second quick connector (11) is connected to the first pipeline (18), and the mobile desulfurization backup device (2) is provided with a first quick connector (10) at the bottom, the first quick connector (10) is connected to the second pipeline (19).

7. The aluminum electrolytic multi-stage flue gas desulfurization system according to claim 6, characterized in that: The mobile desulfurization backup device (2) is equipped with multiple third quick connectors (20) that can be quickly connected to the auxiliary equipment of the fixed desulfurization device (3). The third quick connectors (20) are connected to the flue gas pipeline (6), the process water system (7) and the oxidation air system (8) through pipes and quick connectors respectively.

8. The aluminum electrolytic multi-stage flue gas desulfurization system according to claim 1, characterized in that: The bracket (15) and the bracket connecting bolt (16) are connected. The top of the bracket (15) is bolted to the bottom of the mobile desulfurization backup device housing (12). The housing of the fixed desulfurization device (3) and the mobile desulfurization backup device (2) are detachable in 2-3 layers along the height direction. Each layer of housing is divided into 2 to 10 detachable modules (13) along the length direction. The modules (13) are bolted together and a seal is provided at the connection.

9. A multi-series flue gas desulfurization system for aluminum electrolysis according to claim 1 or 8, characterized in that: Each module (13) of the housing of the fixed desulfurization device (3) and the mobile desulfurization backup device (2) has an edge at the connection point, and the two edges are fixed by bolts, with a seal between the two edges.

10. The aluminum electrolytic multi-stage flue gas desulfurization system according to claim 9, characterized in that: The housing is made of stainless steel corrosion-resistant material of grade 2205 or 316L.

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