A method for removing the GGH module of a desulfurization system

Abstract

This invention relates to the field of maintenance technology, and more particularly to a method for dismantling a desulfurization system GGH module. The method includes the following steps: pre-operation inspection, hoisting mechanism positioning, adjustment and confirmation, hoisting tool positioning, component separation, hoisting and dismantling, and cyclical operation. This invention achieves "side-cut" dismantling of the heat exchange elements under the beam, eliminating the need to dismantle the top main beam or require a large crane to intervene from directly above, greatly reducing construction difficulty and cost. Simultaneously, vertical height adjustment is achieved through a scissor-type telescopic frame, and the I-beam track moves along the main beam via a rack and pinion mechanism. Combined with an electric hoist driven by an electric trolley, this constitutes a two-dimensional horizontal movement system with wide coverage and high positioning accuracy. This achieves point-to-point dismantling, significantly improving operational accuracy and flexibility, replacing the traditional method of radially cutting and dismantling heat exchange elements from the outside in, and shortening the dismantling time for individual heat exchange elements.

Description

Technical Field

[0001] This invention relates to the field of maintenance technology, and in particular to a method for removing the GGH module of a desulfurization system. Background Technology

[0002] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art.

[0003] Rotary flue gas heat exchangers (GGHs) are key equipment in the desulfurization systems of thermal power plants. Their internal rotors are filled with a large number of heat exchange elements (usually enamel-lined heat transfer element boxes). After long-term operation, sticky ash such as ammonium bisulfate will accumulate on the surface of the heat exchange elements, leading to blockage and reduced heat exchange efficiency, requiring regular replacement or offline cleaning.

[0004] Currently, during GGH maintenance, the traditional method for replacing heat exchange elements is to gradually cut and disassemble the elements radially from the outside to the inside. This method suffers from low efficiency and high labor intensity due to manual, step-by-step cutting and disassembly. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned shortcomings by providing a method for removing the GGH module of a desulfurization system.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a method for dismantling a GGH module in a desulfurization system, wherein the GGH module includes heat exchange elements, a rotor, and a shell, and the top of the shell is provided with a beam structure for serving as the main load-bearing structure of the furnace body, specifically including the following steps: S1, Conduct a condition inspection of the GGH module and its surrounding housing to identify any rust, deformation, or weld seam conditions. S2, the positioning mobile hoisting mechanism is placed around the GGH module and positioned on one side of the beam structure; S3, adjust the vertical height of the two-dimensional horizontal moving unit of the mobile hoisting mechanism and confirm that the moving range of the two-dimensional horizontal moving unit can cover all heat exchange elements on the beam structure side of the GGH module; S4, the lifting device of the mobile hoisting mechanism is positioned directly above the target heat exchange element by means of the two-dimensional horizontal moving unit; S5, use a cutting tool to cut off the connecting weld and fasteners between the target heat exchange element and the side wall shell, and complete the separation of the target heat exchange element; S6, the lifting device is lowered and connected to the target heat exchange element by the electric hoist of the mobile lifting mechanism, and then slowly lifted to remove the target heat exchange element from its original installation position and move it to the designated stacking area within the lifting operation radius; S7. Repeat steps S4-S6 to complete the targeted removal of all target heat exchange elements in sequence.

[0007] Furthermore, the mobile hoisting mechanism in step S2 further includes: Side frames, two of which are arranged opposite each other, each of which has a c-shaped structure with an opening at the top; A scissor-type telescopic frame, located inside the side frame and driven and controlled by motor a, is used to adjust the vertical height of the two-dimensional horizontal moving unit; The casters are located at the bottom of the side frame and are symmetrically arranged at both ends along its length, for convenient movement of the mobile hoisting mechanism to the construction work area of ​​the GGH module.

[0008] Furthermore, the two-dimensional horizontal movement unit in step S3 includes: The main beams are two in number and arranged in parallel relative to each other. An I-beam rail is horizontally placed and stacked on two main beams, and driving components are provided at both ends of the I-beam rail for driving the I-beam rail to move along the length direction of the main beams; An electric hoist, mounted on the I-beam rail and equipped with an electric trolley, is used to drive and control the electric hoist to move automatically left and right on the I-beam rail under the movement of the electric trolley.

[0009] Furthermore, the driving component includes a slide table correspondingly disposed at the end of the I-beam rail, a gear disposed in the slide table and driven by motor b, a rack connected to the gear on the corresponding side of the main beam, and a slide rail for linear movement of the slide table on the top surface of the main beam.

[0010] Furthermore, the chain or wire rope of the electric hoist is provided with a lifting ring at the end, and the lifting device has two rings connected to the lifting rings by a flexible rope.

[0011] Furthermore, the motors a and b respectively installed on the two scissor telescopic frames are all connected to the controller, and the two motors a and two motors b are synchronously controlled and driven.

[0012] Furthermore, let one of the two motors a and two motors b have its drive shaft as the master shaft and the other motor's drive shaft as the slave shaft. In each control cycle, the actual positions of the main spindle and the slave spindle are read, the position deviation is calculated, and a speed compensation amount is generated based on the deviation and superimposed on the speed command of the slave spindle so that the slave spindle follows the actual position of the main spindle in real time. The speed compensation amount The calculation formula is as follows:

[0013] In the formula, , The actual position of the main axis The actual position of the axis; , , Online adaptive adjustment or offline tuning can be adopted, among which Used to convert position deviation into velocity compensation, with a range of 5–20 mm·s. - ¹ / mm; Used to eliminate static deviation, its range is 0.1 to 2 s. - ¹; Used to suppress the rate of change of deviation, its range is 0 to 0.5 s; This is the integral of the deviation over time; This is the derivative of the deviation with respect to time.

[0014] Furthermore, the cutting tool in step S5 is a flame cutting tool or a hydraulic shearing tool.

[0015] Furthermore, during dismantling, the heat exchange elements on the other half of the beam structure of the GGH module need to be operated and rotated 180 degrees so that all the heat exchange elements on the other half of the GGH module are placed under the mobile hoisting mechanism.

[0016] Furthermore, the rotor is evenly divided into multiple sector segments along its circumference, and each sector segment is provided with multiple heat exchange zones along the radial direction of the rotor. Each heat exchange zone is provided with heat exchange elements of corresponding specifications, and the shell covers the outer periphery of the rotor.

[0017] The beneficial effects of this invention are reflected in: This invention achieves "side-cut" dismantling of heat exchange elements under the beam by arranging a mobile hoisting mechanism on one side of the top main load-bearing beam structure and combining it with a hoisting unit capable of two-dimensional horizontal movement. This eliminates the need to dismantle the top main beam or require a large crane to intervene from directly above, significantly reducing construction difficulty and cost. Simultaneously, a scissor-type telescopic frame enables vertical height adjustment, and a gear and rack drive I-beam rail moves along the main beam. Combined with an electric hoist driven by an electric trolley, this forms a wide-coverage, high-precision two-dimensional horizontal movement system. A synchronous control algorithm ensures consistent movement of the two motor-driven mechanisms on both sides, avoiding the risk of jamming or overturning due to uneven loading or asynchrony during hoisting. This achieves point-to-point dismantling, greatly improving operational accuracy and flexibility, replacing the traditional method of radially cutting and dismantling heat exchange elements from the outside in, and shortening the dismantling time for individual heat exchange elements. Attached Figure Description

[0018] Figure 1This is a top view of an embodiment of the present invention applied to a GGH module; Figure 2 This is a perspective view of a three-dimensional structure according to an embodiment of the present invention; Figure 3 This is a three-dimensional structural diagram of the GGH module according to an embodiment of the present invention.

[0019] In the picture: 1. Heat exchange element; 2. Rotor; 3. Main beam; 4. Slide rail; 5. Electric trolley; 6. Electric hoist; 7. Lifting device; 8. I-beam rail; 81. Slide table; 9. Rack; 10. Gear; 11. Side frame; 12. Scissor-type telescopic frame; 13. Casters. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Please see Figure 1-3 This invention discloses a method for dismantling a desulfurization system GGH module. The GGH module to be dismantled includes a heat exchange element 1, a rotor 2, and a shell. The top of the shell is equipped with a steel beam structure (not fully shown in the figure, but it forms the basis of this method) to support the weight of the entire GGH and flue. The rotor 2 is evenly divided into 24 sector segments along the circumference. Each sector segment is radially divided into three heat exchange zones: inner, middle, and outer. Each zone is equipped with corrugated plate heat exchange elements 1 of different specifications.

[0022] The specific steps for the demolition are as follows: Step S1: Conduct a comprehensive inspection of the GGH module and its surrounding environment. Identify the corrosion and deformation of all heat exchange elements 1, confirm the location, length, and degree of corrosion of the welds connecting each heat exchange element 1 to the rotor compartment wall and side wall shell, and check the load-bearing capacity and integrity of the top beam structure to ensure it can serve as a support point for the mobile hoisting mechanism.

[0023] Step S2: Move the mobile hoisting mechanism to the side of the GGH module to be removed using the bottom casters 13. Adjust its position so that the mechanism is parallel to one side of the top beam structure. The mobile hoisting mechanism includes: two opposing C-shaped side frames 11, each side frame 11 housing a scissor-type telescopic frame 12 driven by a high-precision servo motor a; the tops of the two scissor-type telescopic frames 12 jointly support a two-dimensional horizontal moving unit. The two-dimensional horizontal moving unit consists of two parallel main beams 3, an I-beam rail 8 spanning the main beams 3, and an electric hoist 6 mounted on the I-beam rail 8.

[0024] It should be noted that the 13 swivel wheels are made from mature products on the market and have a braking structure, allowing for both movement and stable parking.

[0025] The scissor-type telescopic frame 12 is raised and lowered by controlling the forward and reverse rotation of motor a, thereby adjusting the overall vertical height of the upper two-dimensional horizontal moving unit to accommodate heat exchange elements 1 at different heights.

[0026] Furthermore, the main beam 3 is installed at the top of the scissor-type telescopic frame 12. Slides 81 are bolted / welded to both ends of the I-beam track 8, and gears 10 driven by motor b are installed inside the slides 81. A rack 9 and slide rail 4, meshing with the gears 10, are welded to the top surface of the main beam 3. When motor b drives the gears 10 to rotate, the slides 81 move the entire I-beam track 8 along the length of the main beam 3 (Y-axis direction). Simultaneously, the electric hoist 6 is suspended on the lower flange of the I-beam track 8 via an electric trolley 5, and can travel along the I-beam track 8 (X-axis direction) under motor drive.

[0027] Step S3: Based on the height of the top of the heat exchange element 1, synchronously control the two motors a to drive the scissor-type telescopic frame 12 to extend or retract, adjusting the two-dimensional horizontal moving unit to a suitable height. Subsequently, manually or via the controller, test the travel distance (Y direction) of the I-beam rail 8 along the main beam 3 and the travel distance (X direction) of the electric hoist 6 driven by the electric trolley 5 along the I-beam rail 8 to confirm that it can cover all heat exchange elements 1 of the current GGM module located on this side of the beam structure.

[0028] Step S4: Operate the two-dimensional horizontal moving unit: First, drive the I-beam rail 8 to move to the Y coordinate where the target heat exchange element 1 is located, then drive the electric trolley 5 to move the electric hoist 6 to the X coordinate directly above the heat exchange element 1. Ensure that the vertical projection of the lifting device 7 connected below the electric hoist 6 completely covers the target heat exchange element 1.

[0029] Step S5: The operator uses a handheld flame cutting tool (or hydraulic shearing tool) to enter the fan-shaped compartment of rotor 2 and precisely cuts the connecting welds between the target heat exchange element 1 and the compartment wall and the side wall of the shell, as well as all fixing bolts or clips, so that the heat exchange element 1 is completely separated from the shell.

[0030] Step S6: Control the chain or wire rope of the electric hoist 6 to descend, so that the lifting device 7 reaches the lifting holes or preset lifting points on both sides of the heat exchange element 1, and manually connect them securely. Then, the electric hoist 6 slowly lifts up, vertically pulling the heat exchange element 1 out of the rotor compartment. After it is lifted above the upper edge of the shell, it is horizontally moved to the designated temporary stacking platform outside the GGH module by the two-dimensional horizontal moving unit, and then lowered and released.

[0031] Further optimization explains that the lifting device 7 consists of two L-shaped hooks connected to the lifting ring via a flexible rope, which can adapt to the center of gravity of heat exchange elements of different sizes.

[0032] Step S7: Repeat steps S4 to S6 above, and remove all heat exchange elements 1 in the half-zone in sequence from the outer ring to the inner ring and from one side to the other.

[0033] Further optimization involves removing all heat exchange elements 1 on one side of the beam structure, then manually or using a turning device, rotating the rotor 2 of the GGH 180 degrees so that all heat exchange elements 1 originally located on the other side of the beam structure are moved to the underside of the mobile hoisting mechanism. Steps S3 to S7 are then repeated to complete the removal of all heat exchange elements.

[0034] Regarding synchronization control: In this embodiment, in order to ensure that the two scissor telescopic frames 12 maintain height or position synchronization during the lifting process and the two slides 81 maintain height or position synchronization during the movement process, and to prevent structural twisting or jamming, both motors a and two motors b are connected to a PLC controller and a master-slave synchronous control strategy is adopted.

[0035] Taking the synchronization of two slides 81 as an example: The drive shaft of one motor b, located closer to the operating side, is designated as the master shaft, and the other as the slave shaft. Within each control cycle (e.g., 10ms), the controller reads the actual position of the master shaft using a high-precision encoder (position sensor). and the actual position of the axis Calculate positional deviation Then, the speed compensation amount is calculated based on the deviation value. :

[0036] In this embodiment, based on the mechanism load (approximately 1.5 tons) and response speed requirements, the parameters determined by the offline tuning method are as follows: =12mm·s - ¹ / mm, =0.8s - ¹, =0.2s. This compensation amount The speed command is superimposed on the slave shaft in real time, enabling the slave shaft to quickly and smoothly follow the actual movement trajectory of the master shaft. Actual measurements show that during the start-up, constant speed, and deceleration phases, the positional deviation between the master and slave shafts is consistently controlled within ±0.5mm, effectively ensuring the stability of the I-beam rail 8 during movement and avoiding the risk of beam skewing and roller derailment due to one end being ahead or behind. Similarly, the lifting synchronization of the two scissor-type telescopic frames 12 also employs the exact same control strategy, ensuring the levelness of the hoisting platform.

[0037] It should be noted that when the shaft lags ( >0), When positive, the slave axis accelerates to catch up; when the slave axis leads ( <0), If the value is negative, decelerate from the shaft and wait.

[0038] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0039] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0040] Additionally, "multiple" refers to two or more.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for dismantling a GGH module in a desulfurization system, wherein the GGH module includes a heat exchange element (1), a rotor (2), and a shell, and the top of the shell is provided with a beam structure for serving as the main load-bearing structure of the furnace body, characterized in that, Specifically, the following steps are included: S1, Conduct a condition inspection of the GGH module and its surrounding housing to identify any rust, deformation, or weld seam conditions. S2, the positioning mobile hoisting mechanism is placed around the GGH module and positioned on one side of the beam structure; S3, adjust the vertical height of the two-dimensional horizontal moving unit of the mobile hoisting mechanism and confirm that the moving range of the two-dimensional horizontal moving unit can cover all heat exchange elements on the beam structure side of the GGH module (1). S4, the lifting device (7) of the mobile hoisting mechanism is positioned directly above the target heat exchange element (1) by adjusting the two-dimensional horizontal moving unit; S5, use a cutting tool to cut off the connecting weld and fasteners between the target heat exchange element (1) and the side wall shell to complete the separation of the target heat exchange element (1); S6, the electric hoist (6) of the mobile hoisting mechanism drives the lifting device (7) to descend and connect with the target heat exchange element (1), and then slowly lifts it so that the target heat exchange element (1) is removed from its original installation position and moved to the designated stacking area within the hoisting operation radius; S7. Repeat steps S4-S6 to complete the targeted removal of all target heat exchange elements (1) in sequence.

2. The method for removing the GGH module of a desulfurization system according to claim 1, characterized in that, The mobile hoisting mechanism in step S2 further includes: Side frames (11), two of which are arranged opposite each other, each of the side frames (11) having an open top in the shape of a U-shape; A scissor-type telescopic frame (12) is installed inside the side frame (11) and driven and controlled by motor a, used to adjust the vertical height of the two-dimensional horizontal moving unit; The casters (13) are located at the bottom of the side frame (1) and are symmetrically arranged at both ends along its length, for conveniently moving the mobile hoisting mechanism to the construction work area of ​​the GGH module.

3. The method for removing the GGH module of a desulfurization system according to claim 1, characterized in that, The two-dimensional horizontal movement unit in step S3 includes: Main beams (3), two of which are set in parallel relative to each other; I-beam rails (8) are horizontally placed and stacked on the two main beams (3). Both ends of the I-beam rails (8) are provided with driving components for driving the I-beam rails (8) to move along the length direction of the main beams (3). An electric hoist (6) is mounted on the I-beam rail (8) and has an electric trolley (5) for driving and controlling the electric hoist (6) to move automatically left and right on the I-beam rail (8) under the movement of the electric trolley (5).

4. The method for removing the GGH module of a desulfurization system according to claim 3, characterized in that: The driving component includes a slide (81) located at the end of the I-beam rail (8), a gear (10) driven by a motor b located in the slide (81), a rack (9) connected to the gear (10) on the corresponding side of the main beam (3), and a slide rail (4) for linear movement of the slide (81) on the top surface of the main beam (3).

5. The method for removing the GGH module of a desulfurization system according to claim 1, characterized in that: The electric hoist (6) has a lifting ring at the end of its chain or wire rope, and the lifting device (7) has two lifting rings connected to the lifting rings by a flexible rope.

6. The method for removing the GGH module of a desulfurization system according to claim 2 or 4, characterized in that: The motors a on the two scissor telescopic frames (12) and the motors b on the two slides (81) are connected to the controller, and the two motors a and the two motors b are driven synchronously.

7. The method for removing the GGH module of a desulfurization system according to claim 6, characterized in that: Let the drive shaft of one of the two motors a / two motors b be the master shaft and the drive shaft of the other motor be the slave shaft; In each control cycle, the actual positions of the main spindle and the slave spindle are read, the position deviation is calculated, and a speed compensation amount is generated based on the deviation and superimposed on the speed command of the slave spindle so that the slave spindle follows the actual position of the main spindle in real time. The speed compensation amount The calculation formula is as follows: In the formula, , The actual position of the main axis The actual position of the axis; , , Online adaptive adjustment or offline tuning can be adopted, among which Used to convert position deviation into velocity compensation, with a range of 5–20 mm·s. - ¹ / mm; Used to eliminate static deviation, its range is 0.1 to 2 s. - ¹; Used to suppress the rate of change of deviation, its range is 0 to 0.5 s; This is the integral of the deviation over time; This is the derivative of the deviation with respect to time.

8. The method for removing the GGH module of a desulfurization system according to claim 1, characterized in that: The cutting tool mentioned in step S5 is a flame cutting tool or a hydraulic shearing tool.

9. The method for removing the GGH module of a desulfurization system according to claim 1, characterized in that: During dismantling, the heat exchange element (1) located on the other half of the beam structure of the GGH module needs to be operated and rotated 180 degrees so that all the heat exchange elements (1) of the other half of the GGH module are placed under the mobile hoisting mechanism.

10. The method for removing the GGH module of a desulfurization system according to claim 1, characterized in that: The rotor (2) is evenly divided into multiple fan-shaped segments along its circumference. Each fan-shaped segment is provided with multiple heat exchange zones along the radial direction of the rotor (2). Each heat exchange zone is provided with heat exchange elements (1) of corresponding specifications. The shell covers the outer periphery of the rotor (2).

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