Circulating fluidized bed gasification furnace hearth outlet expansion joint refractory sealing structure

Abstract

The utility model discloses a refractory material sealing structure at the expansion joint of the furnace outlet of circulating fluidized bed gasification furnace, relates to the technical field of expansion joint sealing structure. The structure includes two opposite arrangement gap filling blocks, and the elasticity is connected through the built -in guide pipe, guide rod and stretch spring, can the dynamic change of self -adaptation expansion gap width. One gap filling block is equipped with rubber sealing frame body, and its " tongue department " extends into another filling block inner chamber, and forms dynamic main seal, and the contact end face of two filling blocks still is equipped with sealed rubber pad and is used as auxiliary seal. The both sides of structure are equipped with elastic mounting piece and realize stable assembly, and are equipped with limit mechanism and prevent excessive displacement. The scheme passes through the elastic self -adaptation and double -sealed design, and effectively solved the problem of the sealing failure of traditional rigid expansion joint under the complex thermal condition, and the obvious barrier of flue gas and the penetration of furnace ash, improves the furnace wall tightness, the service life and the operating energy efficiency of boiler.

Description

Technical Field

[0001] This utility model relates to the technical field of expansion joint sealing structure, and in particular to the refractory material sealing structure at the expansion joint of the furnace outlet of a circulating fluidized bed gasifier. Background Technology

[0002] During long-term high-temperature operation, boiler furnace walls require expansion joints to release structural stress and prevent cracking or damage due to thermal expansion and contraction. Traditional expansion joint structures often use Z-shaped fiber felt filling, such as the "expansion joint structure for boiler furnace walls" proposed in Chinese utility model patent CN206556062U. This structure improves the traditional Z-shaped expansion joint into a longitudinally arranged "1"-shaped expansion joint, aiming to avoid the formation of continuous flue gas channels due to the evacuation of the fiber felt, thereby reducing the amount of ash entering the insulation layer, reducing air leakage, and extending the service life of the furnace wall.

[0003] However, the aforementioned "1"-shaped expansion joint structure still has certain limitations in practical applications. This structure is essentially a rigid gap design with a fixed width, and its expansion compensation capability depends on the preset gap width and arrangement. Under long-term, unstable, or overloaded boiler operation conditions, the temperature distribution in different areas of the furnace wall is uneven, leading to differences in the amount and rate of expansion. A fixed "1"-shaped expansion joint cannot dynamically adapt to this complex and uneven thermal deformation, and is prone to losing its effective sealing function due to localized stress concentration. It may still form a channel for flue gas and ash penetration, affecting the sealing performance and overall durability of the furnace wall.

[0004] Furthermore, with the development of high-efficiency combustion technologies such as circulating fluidized bed combustion, higher requirements are placed on the sealing performance of expansion joints in key components such as the furnace outlet. Especially in harsh environments with high temperature, high wear, and high gas-solid two-phase flow erosion, expansion joints not only need to have good thermal compensation capabilities, but also need to achieve continuous, adaptive, and recoverable dynamic sealing to prevent the leakage of flue gas and dust, and ensure the safety and energy efficiency of system operation. Therefore, there is an urgent need for an expansion joint sealing structure that can adapt to uneven thermal expansion, has dynamic adaptive sealing capability, is structurally reliable and easy to implement, in order to overcome the sealing failure problem of existing fixed expansion joints under complex working conditions, and further improve the long-term operational stability and energy efficiency of boilers and similar high-temperature equipment furnace walls. Utility Model Content

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a refractory material sealing structure at the expansion joint of the furnace outlet of a circulating fluidized bed gasifier.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a refractory material sealing structure at the expansion joint of the furnace outlet of a circulating fluidized bed gasifier, two inter-contact gap filling blocks, each of the two gap filling blocks having an installation groove on its inter-contact surface, the two installation grooves being elastically connected, a rubber sealing frame being fitted into the inner cavity of one of the gap filling blocks, and one end of the rubber sealing frame extending into the inner cavity of the other gap filling block.

[0007] Preferably, sealing rubber pads are installed on the sides of the two gap filling blocks that are in contact with each other, and the sides of the two sealing rubber pads are in contact with each other.

[0008] Preferably, each of the two gap filling blocks has a plurality of guide tubes and guide rods installed in its inner cavity. One end of the guide rod extends into the guide tube, and a tension spring is sleeved between the surfaces of the guide tube and the guide rod. The two ends of the tension spring are respectively installed at one end of the guide tube and the guide rod.

[0009] Preferably, elastic mounting elements are installed on both symmetrical sides of the two gap filling blocks.

[0010] Preferably, a plurality of limiting mechanisms are provided between the two gap filling blocks. The limiting mechanism includes a mounting block, one end of which is mounted on the side of one of the gap filling blocks, and the other end of which extends to the side of the other gap filling block. The other end of the mounting block has an elongated hole. A stud is mounted on the side of the other gap filling block, and one end of the stud extends into the elongated hole.

[0011] Compared with the prior art, the present invention has the following beneficial effects: This invention provides an expansion joint structure with elastic adaptive sealing, effectively overcoming the inherent defect of insufficient sealing performance of traditional fixed expansion joints under complex thermal conditions, and specifically achieving the following beneficial effects: 1. Dynamic adaptive compensation for uneven thermal expansion is achieved. This utility model adopts two elastically connected gap filling blocks and a built-in guide tube, guide rod and tension spring system, so that the expansion joint structure can adjust the spacing in real time and automatically during the thermal expansion and contraction of the furnace wall, adapt to the expansion deformation of different areas and different rates, avoid local stress concentration and sealing failure caused by uneven expansion, and significantly improve the adaptability and reliability of the structure under complex working conditions.

[0012] 2. A continuous and effective main-auxiliary coordinated sealing mechanism has been established. Through the dual sealing design of the rubber sealing frame ("tongue" type main seal) and the sealing rubber gasket (end face auxiliary seal), a tight contact and blockage are maintained throughout the entire process of expansion joint width change, effectively blocking the intrusion path of flue gas and furnace ash, and fundamentally solving the technical problem that traditional fiber felt or rigid gaps are prone to forming flue gas channels.

[0013] 3. Enhanced overall structural stability and maintainability. The flexible mounting components not only absorb installation stress and minor masonry deformations but also improve the installation stability of the gap filler blocks in expansion joints. The limiting mechanism, through the cooperation of elongated holes and studs, ensures that the structure can freely expand and contract within a preset range while preventing component separation or elastic element failure due to excessive displacement, thus guaranteeing the long-term operation of the sealing system. Furthermore, key components such as guide tubes and guide rods are connected with screws, facilitating disassembly and maintenance and improving the structure's maintainability.

[0014] 4. Significantly improves furnace wall sealing performance and equipment operating efficiency. This structure fundamentally improves the sealing effect of expansion joints, significantly reduces air leakage, minimizes heat loss and flue gas leakage, thereby optimizing boiler combustion efficiency and heat transfer performance. Simultaneously, it effectively prevents furnace ash from entering the insulation layer, extending the service life of the furnace wall and related refractory materials, reducing maintenance frequency and operating costs, resulting in significant economic and safety improvements.

[0015] In summary, this utility model not only solves the key problems mentioned in the background art, such as the difficulty of fixed expansion joints adapting to uneven thermal expansion and the easy loss of sealing function, but also achieves durable and reliable sealing of expansion joints in high-temperature dynamic environments through elastic self-adaptation, multiple sealing and structural optimization, providing strong technical support for the long-term safe and efficient operation of high-temperature equipment such as boilers and gasifiers. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a schematic diagram of the connection structure between the tension spring and the guide tube of this utility model; Figure 3 This is a schematic diagram of the connection structure of the tension spring, guide tube, and guide rod of this utility model; Figure 4 This is a schematic diagram of the connection structure between the mounting block and the stud of this utility model; Figure 5 This is a schematic diagram of the connection structure between the gap filling block and the rubber sealing frame of this utility model.

[0017] In the diagram: 1. Mounting block; 2. Sealing rubber gasket; 3. Gap filler block; 4. Elastic mounting component; 5. Tension spring; 6. Guide tube; 7. Rubber sealing frame; 8. Guide rod; 9. Stud; 10. Long hole. Detailed Implementation

[0018] The following description is intended to disclose the present invention so that those skilled in the art can implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.

[0019] This embodiment provides a refractory material sealing structure at the expansion joint of the furnace outlet of a circulating fluidized bed gasifier. For example... Figure 1 As shown, the structure mainly consists of two parallel gap-filling blocks 3, which together fill the expansion joints reserved in the furnace wall or refractory masonry. The gap-filling blocks 3 are made of materials with excellent high-temperature resistance and thermal shock resistance, such as high-temperature alloy steel or special refractory ceramic materials, to adapt to the high-temperature and thermal cycling environment inside the furnace.

[0020] On the contact surfaces of the two gap-filling blocks 3, which are close to each other, a mounting groove is provided. These two mounting grooves are positioned opposite each other to accommodate and connect a set of elastic expansion systems. For example... Figure 2 and Figure 3 As shown, the elastic expansion system consists of a guide tube 6, a guide rod 8, and a tension spring 5. The guide tube 6 is fixed inside the cavity of one of the gap-filling blocks 3, while the guide rod 8 is fixed inside the cavity of the other gap-filling block 3, with their axes aligned. The end of the guide rod 8 is inserted into the guide tube 6 and can slide freely along its axis. Tension springs 5 ​​are fitted onto the outer surfaces of the guide tube 6 and the guide rod 8, with both ends of the springs fixed to the ends of the guide tube 6 and the guide rod 8, respectively. Thus, the two gap-filling blocks 3 are elastically connected through multiple sets (usually 2-4 sets evenly arranged along the height direction) of this guide-spring system. When the furnace wall expands or contracts due to temperature changes, causing the two gap-filling blocks 3 to tend to move closer or further apart, the guide rod 8 slides within the guide tube 6, and the tension spring 5 is compressed or stretched, generating an elastic restoring force opposite to the direction of displacement. This allows the two gap-filling blocks 3 to adaptively follow changes in the gap width while maintaining a tight contact tendency.

[0021] The sealing function is achieved through a two-stage sealing structure. The first stage is the main seal, such as... Figure 5As shown, a rubber sealing frame 7 made of high-temperature resistant silicone rubber is pre-embedded and installed in the inner cavity of a gap filler block 3. One end of the rubber sealing frame 7 (which can be figuratively understood as a "tongue") extends out of the gap filler block 3 and is tightly inserted into the corresponding groove or space in the inner cavity of another gap filler block 3, forming a "tongue" structure. This design allows the "tongue" of the rubber sealing frame 7 to maintain contact with the other filler block even when the two gap filler blocks 3 are relatively displaced, dynamically sealing any possible through gaps and effectively preventing the passage of high-temperature flue gas and dust. The second stage is an auxiliary seal, such as... Figure 1 As shown, sealing rubber gaskets 2 are respectively pasted or embedded on the end faces of the two gap filling blocks 3 that are in contact with each other. The sealing rubber gaskets 2 can be made of materials such as high-temperature resistant graphite composite gaskets or flexible ceramic fiber gaskets. After the two gap filling blocks 3 are installed in place, the sealing rubber gaskets 2 on their end faces are pressed together, providing an initial end face seal, and together with the rubber sealing frame 7, they form a redundant sealing barrier.

[0022] To ensure the entire sealing structure is securely installed within the expansion joint and to allow for slight floating with the furnace wall to avoid rigid constraints, elastic mounting elements 4 are installed on the outer surfaces (i.e., the surfaces in contact with the refractory material of the furnace wall) of the two gap filling blocks 3 on both sides. The elastic mounting elements 4 can be made of high-temperature resistant metal spring sheets or elastic ceramic fiber blocks. Through their own elastic deformation, they both press and fix the gap filling blocks 3 within the expansion joint and absorb minor irregular deformations or vibrations of the refractory masonry itself, preventing stress from being directly transmitted to the main sealing structure.

[0023] Furthermore, to prevent excessive relative displacement between the two gap-filling blocks 3 under extreme or irregular expansion conditions, which could lead to spring overload failure or structural detachment, a limiting mechanism is provided. For example... Figure 4 As shown, the limiting mechanism includes a mounting block 1, one end of which is fixed to the side of a gap-filling block 3 by bolts or welding. The other end of the mounting block 1 extends towards another gap-filling block 3, and has an elongated hole 10 at that end. A stud 9 is fixed at a corresponding position on the other gap-filling block 3, with the end of the stud 9 extending into the elongated hole 10. The length direction of the elongated hole 10 is consistent with the opening and closing direction of the expansion joint. This structure allows the stud 9 to slide within the elongated hole 10, thereby providing a preset free stroke for the relative movement of the two gap-filling blocks 3. When the displacement reaches the stroke limit, the stud 9 will contact the end of the elongated hole 10, preventing further displacement and serving as a safety limiting mechanism.

[0024] Brief description of installation and operation process: 1. When constructing the furnace wall, reserve space for installing the expansion joint sealing structure according to the design requirements.

[0025] 2. Place the assembled rubber sealing frame 7, guide tube 6 / rod 8 / spring 5 system, sealing rubber gasket 2, elastic mounting part 4 and the two gap filling blocks 3 of the limiting mechanism as a whole into the reserved expansion joint.

[0026] 3. Relying on the elastic force of the elastic mounting part 4, the component is initially stabilized in the gap (it should be noted that the elastic mounting part 4 is made of metal and can be directly inserted into the gap of the furnace wall for installation).

[0027] 4. When the boiler starts up and heats up, the expansion joint narrows due to the expansion of the furnace wall. The two gap filling blocks 3 are squeezed, the guide rod 8 slides deeper into the guide tube 6, the tension spring 5 is compressed, and energy is stored. The "tongue" of the rubber sealing frame 7 is pressed tight, the contact pressure of the sealing gasket 2 increases, and the sealing effect is enhanced.

[0028] 5. When the boiler stops operating and cools down, the expansion joint widens due to the shrinkage of the furnace wall. The tension spring 5 releases energy, pushing the guide rod 8 partially out of the guide tube 6, so that the two gap filling blocks 3 follow under the spring force, avoiding excessive gaps. The rubber sealing frame 7 stretches due to its elasticity, continuously sealing the gap, while the sealing gasket 2 remains in contact.

[0029] Throughout the thermal cycle, the limiting mechanism ensures that the relative displacement remains within a safe range, protecting the elastic elements and sealing structure from damage.

[0030] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A refractory sealing structure at the expansion joint of the furnace outlet of a circulating fluidized bed gasifier, comprising two contacting gap-filling blocks (3), characterized in that, The two gap filling blocks (3) have mounting grooves on their contact surfaces and are elastically connected. A rubber sealing frame (7) is installed in the inner cavity of one of the gap filling blocks (3) and one end of the rubber sealing frame (7) extends into the inner cavity of the other gap filling block (3).

2. The refractory material sealing structure at the expansion joint of the circulating fluidized bed gasifier furnace outlet according to claim 1, characterized in that, Both of the two gap filling blocks (3) have sealing rubber pads (2) installed on their contacting sides, and the two sealing rubber pads (2) are in contact with each other.

3. The refractory material sealing structure at the expansion joint of the circulating fluidized bed gasifier furnace outlet according to claim 1, characterized in that, Multiple guide tubes (6) and guide rods (8) are respectively installed in the inner cavity of the two gap filling blocks (3). One end of the guide rod (8) extends into the guide tube (6). A tension spring (5) is sleeved between the surfaces of the guide tube (6) and the guide rod (8). The two ends of the tension spring (5) are respectively installed at one end of the guide tube (6) and the guide rod (8).

4. The refractory material sealing structure at the expansion joint of the circulating fluidized bed gasifier furnace outlet according to claim 1, characterized in that, Both sides of the two gap filling blocks (3) are fitted with elastic mounting parts (4).

5. The refractory material sealing structure at the expansion joint of the circulating fluidized bed gasifier furnace outlet according to claim 1, characterized in that, Multiple limiting mechanisms are provided between the two gap filling blocks (3). The limiting mechanism includes a mounting block (1). One end of the mounting block (1) is installed on the side of one of the gap filling blocks (3), and the other end of the mounting block (1) extends to the side of the other gap filling block (3). An elongated hole (10) is opened at the other end of the mounting block (1). A stud (9) is installed on the side of the other gap filling block (3), and one end of the stud (9) extends into the elongated hole (10).

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