Plug seal device for flue gas desulfurization tower

Abstract

The application provides a flue gas desulfurization tower plug sealing device, which comprises a vertical frame, a rotating plug assembly, a crank, a connecting rod assembly, a bearing seat and a driving mechanism, the vertical frame is fixedly installed on a flue, three bearing seats are vertically and spacedly arranged on the vertical frame, each bearing seat is connected with one rotating plug assembly, the rotating plug assembly comprises a rotating shaft horizontally extending into the flue and a plug arranged on the rotating shaft and rotating with the rotating shaft to open and close the flue, bearings are arranged on each bearing seat and the rotating shaft is horizontally connected with the bearings through the bearings, one end of the rotating shaft connected with the bearings is fixedly connected with the crank, the three cranks are connected through the connecting rod assembly, the connecting rod assembly comprises a plurality of connecting rods hingedly connected with the cranks, and the output end of the driving mechanism is in transmission connection with the connecting rod assembly to drive the cranks to rotate by pushing and pulling the connecting rod assembly. The application can reduce the air leakage rate and has high practicability through the parallel and synchronous structure of multiple plugs.

Description

Technical Field

[0001] This application relates to the field of flue gas treatment equipment technology, and in particular to a flue gas desulfurization tower insert sealing device. Background Technology

[0002] With increasingly stringent environmental protection requirements and the advancement of the aluminum electrolysis industry's dual carbon goals of "carbon peaking and carbon neutrality," higher demands have been placed on the efficiency and emission standards of aluminum electrolysis flue gas desulfurization systems. Fully enclosed operation of desulfurization systems has become an industry trend.

[0003] Existing flue gas desulfurization tower baffle sealing devices mostly use traditional hydraulic or pneumatically driven single-plate baffle gates for flue gas isolation and opening / closing. However, such devices have poor sealing performance in high-temperature and high-corrosion environments and are prone to air leakage. Utility Model Content

[0004] This application provides a flue gas desulfurization tower insert sealing device to solve the problem of poor sealing performance of existing single insert baffle doors driven by traditional hydraulic or pneumatic methods.

[0005] This application provides a flue gas desulfurization tower insert sealing device, including a vertical frame, a rotating insert assembly, a crank, a connecting rod assembly, a bearing seat, and a drive mechanism. The vertical frame is fixedly installed on the flue. Three bearing seats are arranged vertically at intervals on the vertical frame. Each bearing seat is connected to a rotating insert assembly. The rotating insert assembly includes a rotating shaft with one end horizontally extending into the flue and an insert plate disposed on the rotating shaft and located in the flue, rotating together with the rotating shaft to open and close the flue. Each bearing seat is equipped with a bearing and is horizontally connected to the rotating shaft through the bearing. A crank is fixedly connected to one end of the rotating shaft connected to the bearing. The three cranks are connected to each other through a connecting rod assembly. The connecting rod assembly includes multiple connecting rods hinged to the cranks. The output end of the drive mechanism is drively connected to the connecting rod assembly to drive each crank to rotate by pushing and pulling the connecting rod assembly.

[0006] In one alternative embodiment, each of the rotating shafts is provided with a shaft seal assembly at the point where it enters the flue. The shaft seal assembly includes a bushing fixed to the flue wall, a flexible graphite packing filled between the bushing and the rotating shaft, and a pressure cap that presses the flexible graphite packing. The flexible graphite packing can be tightly attached to the surface of the rotating shaft under the pressing action of the pressure cap to form a dynamic seal.

[0007] In one alternative embodiment, the drive mechanism includes a servo motor and a planetary gear reducer, wherein the servo motor is connected to the linkage assembly via the planetary gear reducer.

[0008] In one optional embodiment, the bearing installed in the bearing housing is a graphite self-lubricating bearing.

[0009] In one alternative embodiment, the bearing is a copper-graphite bearing.

[0010] In one optional embodiment, the vertical frame is a single-sided open vertical steel plate welded structure, and multiple plate-shaped reinforcing ribs are provided between the side plates of the vertical frame. The three bearing seats are welded together and protrude from the vertical frame at intervals along the vertical direction.

[0011] In one alternative embodiment, the connecting rods of the connecting rod assembly are hinged to the crank via pins.

[0012] In one alternative embodiment, the insert plate is made of 316L stainless steel with a ceramic fiber composite layer on its surface.

[0013] Compared with the prior art, this application has the following beneficial effects: This application provides a flue gas desulfurization tower insert sealing device, which connects to a rotating insert assembly via three bearing seats spaced vertically along a vertical frame. The parallel structure of the crank and connecting rod assembly enables synchronous operation under single-point drive, allowing multiple inserts to rotate synchronously and in a coordinated manner to open and close the flue. Compared with the traditional single insert design, this device improves the efficiency of flue duct sealing operation and achieves reliable sealing of the flue section, thereby significantly reducing the air leakage rate and improving the overall sealing performance. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 A schematic diagram of the overall structure of the flue gas desulfurization tower insert sealing device provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a shaft seal assembly provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of a rotating insert assembly provided in an embodiment of this application.

[0016] Figure label: 100-Vertical frame, 110-Plate-shaped reinforcing rib, 200-Rotating insert plate assembly, 210-Rotating shaft, 220-Insert plate, 300-Crank, 400-Connecting rod assembly, 410-Connecting rod, 500-Bearing housing, 510-Bearing, 600-Drive mechanism, 610-Servo motor, 620-Planetary reducer, 700-Shaft seal assembly, 710-Shaft sleeve, 720-Flexible graphite packing, 730-Glander cap. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are also within the scope of protection of this application.

[0018] like Figures 1-3 As shown, this application embodiment provides a flue gas desulfurization tower insert sealing device, including a vertical frame 100, a rotating insert assembly 200, a crank 300, a connecting rod assembly 400, a bearing seat 500, and a drive mechanism 600. The vertical frame 100 is fixedly installed on the flue. Three bearing seats 500 are vertically spaced on the vertical frame 100, and each bearing seat 500 is connected to a rotating insert assembly 200. Figure 3 As shown, the rotary insert plate assembly 200 includes a rotating shaft 210 with one end horizontally extending into the flue and an insert plate 220 disposed on the rotating shaft 210 and located within the flue. The insert plate 220 can rotate together with the rotating shaft 210 to realize the opening and closing of the flue. Each bearing seat 500 is equipped with a bearing 510 and is horizontally connected to the rotating shaft 210 through the bearing 510. One end of the rotating shaft 210 connected to the bearing 510 is fixedly connected to a crank 300. The three cranks 300 are connected to each other through a connecting rod assembly 400. The connecting rod assembly 400 includes multiple connecting rods 410 hinged to the cranks 300. The output end of the drive mechanism 600 is connected to the connecting rod assembly 400 for transmission so as to drive each crank 300 to rotate by pushing and pulling the connecting rod assembly 400.

[0019] In the above embodiment, a vertical frame 100 is fixedly installed on the flue, with three bearing seats 500 spaced vertically along its upper edge. Each bearing seat 500 is connected to a rotating insert plate assembly 200. The rotating insert plate assembly 200 includes a rotating shaft 210 with one end horizontally extending into the flue and an insert plate 220 fixed on the rotating shaft 210 and located within the flue. The insert plate 220 rotates with the rotating shaft 210 to open and close the flue. This spaced distribution of the bearing seats 500 allows the three independent rotating shafts 210 to be distributed vertically. Each rotating shaft 210 is horizontally supported by a corresponding bearing seat 500 via a bearing 510, enabling the synchronous operation of the three rotating shafts 210 to be linked to the connecting rod assembly 400. This reduces the risk of deformation of a single rotating shaft due to excessive span. Furthermore, the insert plate 220 maintains a relatively stable planar posture when rotating, resulting in a more uniform contact surface with the flue wall, thereby reducing local gaps during closure and improving overall sealing performance.

[0020] Meanwhile, in this embodiment, each bearing housing 500 is connected to a corresponding rotating shaft 210 with a crank 300 fixed at its outer end. The three cranks 300 are connected to each other via a connecting rod assembly 400, which includes multiple connecting rods 410 hinged to the cranks 300. The output end of the drive mechanism 600 is connected to the connecting rod assembly 400 for transmission, and drives each crank 300 to rotate by pushing and pulling the connecting rod assembly 400. This parallel connection of the cranks 300 and the connecting rod assembly 400 disperses the driving force to the three cranks 300, making the rotation angle and speed tend to be consistent. After the rotation is synchronized, the three insert plates 220 reach the closed position simultaneously, reducing temporary leakage caused by differences in the timing of actions and further improving the sealing uniformity of the entire flue section.

[0021] Furthermore, although the three rotating insert plate assemblies 200 in this embodiment are arranged independently, they are synchronized through the connecting rod assembly 400, dividing the part of the flue that needs to be sealed into three areas. Each insert plate 220 undertakes the sealing task, thereby reducing the size and weight of a single insert plate 220 in practical applications, and reducing deformation caused by thermal expansion and gravity. In addition, through the combined action of the connecting rod assembly 400, the complex setup of multiple drive sources is avoided, reducing the difficulty of installation and maintenance, and improving the practicality of the device while maintaining sealing reliability.

[0022] In some embodiments, each rotating shaft 210 is provided with a shaft seal assembly 700 at the point where it enters the flue, such as... Figure 2 As shown, the shaft seal assembly 700 includes a bushing 710 fixed to the flue wall, a flexible graphite packing 720 filled between the bushing 710 and the rotating shaft 210, and a cap 730 that presses the flexible graphite packing 720. The flexible graphite packing 720 can be tightly attached to the surface of the rotating shaft 210 under the pressing action of the cap 730 to form a dynamic seal.

[0023] In the above embodiments, the bushing 710 is typically made of stainless steel and is fixed to a pre-drilled opening in the flue wall using flange bolts. The inner diameter of the bushing 710 is slightly larger than the outer diameter of the rotating shaft 210, forming an annular gap. In practical applications, the flexible graphite packing 720 is braided or expanded graphite packing, which is installed in multiple loops to fill the gap, with a filling thickness typically of 10-20 mm. The gland 730 is a circular flange that is pressed into the bushing 710 from outside the flue. It is then gradually tightened using 4-8 evenly distributed bolts, causing the flexible graphite packing 720 to expand radially and tightly wrap around the surface of the rotating shaft 210. This structure reduces friction by utilizing the self-lubricating properties of graphite when the rotating shaft 210 rotates at low speeds, while maintaining a reliable seal. It is suitable for high-temperature and highly corrosive flue gas environments, and routine maintenance only requires periodic inspection and tightening of the bolts.

[0024] In some embodiments, the drive mechanism 600 includes a servo motor 610 and a planetary reducer 620, wherein the servo motor 610 is connected to the link assembly 400 via the planetary reducer 620.

[0025] The servo motor 610 is a three-phase asynchronous or permanent magnet synchronous motor with an output torque of 2000-5000 N·m. It is mounted on a platform outside the lower part of the vertical frame 100 and connected to the input end of the planetary reducer 620 via a coupling. The planetary reducer 620 typically has a reduction ratio of 10:1 to 50:1, and its output shaft is hinged to the lowermost connecting rod 410 in the connecting rod assembly 400 via a bent arm. In actual operation, the servo motor 610 can be controlled to rotate forward and backward via a PLC to achieve remote or local start and stop. The start and stop time can be controlled within 30 seconds, with smooth operation and sufficient torque, adapting to frequent switching conditions.

[0026] In some embodiments, the bearing 510 installed in the bearing housing 500 is a graphite self-lubricating bearing. Optionally, the bearing 510 is a copper-graphite bearing.

[0027] The copper-graphite bearing 510 uses a high-strength copper alloy as its base, with solid graphite lubricant embedded on its surface or inside. During installation, it is directly pressed into or embedded in the inner bore of the bearing housing 500. The inner bore of the bearing 510 mates with the rotating shaft 210 using a transition fit, facilitating assembly while limiting radial movement. This type of bearing requires no additional grease lubrication, exhibits a low coefficient of friction in dusty and highly corrosive environments, and has a long service life. In practical applications, the bearings 510 in the upper, middle, and lower bearing housings 500 collectively provide radial support, while the shoulders or retaining rings of the rotating shaft 210 achieve axial positioning, resulting in smooth and reliable overall operation.

[0028] In some embodiments, the vertical frame 100 is a single-sided open vertical steel plate welded structure, and a plurality of plate-shaped reinforcing ribs 110 are provided between the side plates of the vertical frame 100. Three bearing seats 500 are welded and protruded along the vertical interval of the vertical frame 100.

[0029] In the above embodiments, the vertical frame 100 can be welded from 10-20mm thick Q235 or stainless steel plates. The single-sided open design facilitates installation and maintenance of the rotating shaft 210 and related components from one side. Multiple plate-shaped reinforcing ribs 110, 50-100mm wide, are welded along the height of the vertical frame 100 to improve its bending and vibration resistance. The bearing housing 500 is a prefabricated square or rectangular block, directly welded to the vertical frame 100. After welding, it undergoes grinding and flaw detection to ensure strength.

[0030] In some embodiments, each link 410 of the link assembly 400 is hinged to the crank 300 by a pin.

[0031] In practical applications, stainless steel pins with a diameter of 20-40mm are generally selected for the pin shaft, and cotter pins or nuts are used to prevent them from coming loose. A sleeve or self-lubricating bushing can be added to the hinge joint to reduce wear. The connecting rod 410 is a straight rod with eyelets machined at both ends. It is aligned with the end of the crank 300 and then inserted into the pin shaft for fixation. This hinged joint allows for a certain degree of angular oscillation, compensating for installation errors and thermal expansion, while ensuring reliable force transmission. In actual assembly, the connecting rods 410 and crank 300 are connected sequentially from one end of the drive mechanism 600. After adjustment, tightening the pin shaft completes the transmission chain, resulting in flexible operation and simple maintenance.

[0032] In some embodiments, the insert plate 220 is made of 316L stainless steel with a ceramic fiber composite layer on its surface.

[0033] In the above embodiments, the substrate of the insert plate 220 is cut and formed from a 5-10mm thick 316L stainless steel plate to ensure corrosion resistance. The ceramic fiber composite layer, 1-2mm thick, is bonded to the flue gas-facing surface of the insert plate 220 by high-temperature bonding or mechanical fixing to improve temperature resistance and wear resistance. The edges of the insert plate 220 can be processed into a flat or sealed groove structure to facilitate fitting with the flue wall when closed. After manufacturing, overall leveling is performed to ensure flatness within 2mm. During installation, the insert plate 220 is fixed to the middle of the rotating shaft 210 by a key or bolt. Rotating ±90° with the shaft can achieve full opening or full closing of the flue, resulting in a simple structure and good sealing effect.

[0034] In aluminum electrolysis flue gas desulfurization systems, flue ducts typically require the use of baffle plate sealing devices, primarily for switching and isolating multiple flue ducts during the treatment process. For example, during desulfurization tower maintenance or emergency shutdown, the relevant flue ducts must be quickly shut down to prevent untreated flue gas from leaking out or backflowing into other systems. This device achieves reliable opening and closing of the flue ducts through the rotation of the baffle plate 220 along with the rotating shaft 210, thereby helping to maintain the overall stable operation of the system and reducing the risk of environmental pollution.

[0035] This device is well-suited for aluminum electrolysis flue gas emission scenarios. Aluminum electrolysis flue gas has high temperatures (>150℃), is highly corrosive (containing HF, SO2, and dust), and has stringent emission standards (requiring SO2 <35mg / Nm³). 3 HF < 0.5 mg / Nm 3 In practical use, this device can generally be installed on the inlet or outlet flue of the desulfurization tower. During normal system operation, the drive mechanism 600 opens the baffle plate 220, allowing smooth flue gas flow. When isolation is required, the drive mechanism 600 drives the connecting rod assembly 400 and the crank 300, causing the three baffle plates 220 to simultaneously close the flue, blocking the flue gas flow and achieving reliable isolation.

[0036] As the core equipment for treating flue gas from aluminum electrolysis, the desulfurization tower primarily employs the limestone-gypsum wet process or other techniques to absorb pollutants such as SO2 and HF. This unit, as an auxiliary component of the desulfurization tower, focuses on flue gas control and works closely in tandem with the desulfurization process. When the flue is closed, it facilitates normal circulation of the slurry within the tower and the dehydration of the gypsum; when the flue is open, it ensures that the flue gas enters the absorption zone of the tower evenly. The main uses of this unit include emergency isolation, system switching, and maintenance shutdown. It supports the fully enclosed operation of the desulfurization system and is highly practical.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A flue gas desulfurization tower insert sealing device, characterized in that, The device includes a vertical frame, a rotating insert plate assembly, cranks, a connecting rod assembly, bearing seats, and a drive mechanism. The vertical frame is fixedly installed on the flue. Three bearing seats are arranged vertically at intervals on the vertical frame. Each bearing seat is connected to a rotating insert plate assembly. The rotating insert plate assembly includes a rotating shaft with one end horizontally extending into the flue and an insert plate disposed on the rotating shaft and located inside the flue, rotating together with the rotating shaft to open and close the flue. Each bearing seat is equipped with a bearing and is horizontally connected to the rotating shaft through the bearing. A crank is fixedly connected to one end of the rotating shaft connected to the bearing. The three cranks are connected to each other through a connecting rod assembly. The connecting rod assembly includes multiple connecting rods hinged to the cranks. The output end of the drive mechanism is driven by the connecting rod assembly to drive each crank through pushing and pulling the connecting rod assembly.

2. The flue gas desulfurization tower insert sealing device according to claim 1, characterized in that, Each of the rotating shafts is provided with a shaft seal assembly at the point where it enters the flue. The shaft seal assembly includes a bushing fixed to the flue wall, a flexible graphite packing filled between the bushing and the rotating shaft, and a pressure cap that presses the flexible graphite packing. The flexible graphite packing can be tightly attached to the surface of the rotating shaft under the pressing action of the pressure cap to form a dynamic seal.

3. The flue gas desulfurization tower insert sealing device according to claim 1, characterized in that, The drive mechanism includes a servo motor and a planetary reducer, and the servo motor is connected to the connecting rod assembly via the planetary reducer.

4. The flue gas desulfurization tower insert sealing device according to claim 1, characterized in that, The bearing installed in the bearing housing is a graphite self-lubricating bearing.

5. The flue gas desulfurization tower insert sealing device according to claim 4, characterized in that, The bearing is a copper-graphite bearing.

6. The flue gas desulfurization tower insert sealing device according to claim 1, characterized in that, The vertical frame is a single-sided open vertical steel plate welded structure. Multiple plate-shaped reinforcing ribs are provided between the side plates of the vertical frame. The three bearing seats are welded and protrude from the vertical frame at intervals along the vertical direction.

7. The flue gas desulfurization tower insert sealing device according to claim 1, characterized in that, The connecting rods of the connecting rod assembly are hinged to the crank via pins.

8. The flue gas desulfurization tower insert sealing device according to claim 1, characterized in that, The insert plate is made of 316L stainless steel with a ceramic fiber composite layer on the surface.

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