Coal falling port anti-abrasion structure of circulating fluidized bed gasifier

Abstract

The utility model discloses a kind of circulating fluidized bed gasification furnace coal drop mouth anti-abrasion structures, it is related to coal drop mouth anti-abrasion structure technical field, including two vertical misplacement settings coal conveying pipeline and its first anti-collision plate and second anti-collision plate installed on it. Multiple coal cone bodies are installed on the board surface of two anti-collision plates, and multiple guide shear blocks are distributed on the sidewall of each cone body. When coal block falls, first be pricked into crack by cone tip, then be sheared and broken by guide shear block, realize efficient particle size control. Coal cone body is detachably installed on anti-collision plate by thread connection, and it is convenient to maintain and replace. Coal conveying pipeline is provided with fine material outlet and coarse material outlet to realize pre-screening, and uniform airflow is introduced through perforated plate and air vent to assist breaking. The structure has high breaking efficiency, strong wear resistance and convenient maintenance, which can effectively reduce the impact and wear of the lining and coal drop mouth in the furnace.

Description

Technical Field

[0001] This utility model relates to the technical field of anti-wear structure for coal chutes, and in particular to an anti-wear structure for the coal chutes of a circulating fluidized bed gasifier. Background Technology

[0002] As a highly efficient and clean energy conversion device, the circulating fluidized bed gasifier requires a continuous supply of fuel coal during operation. However, during the descent of coal, especially large pieces, there is a strong impact and abrasion on the coal inlet, the inner wall of the furnace, and the refractory bricks being fired, severely affecting the equipment's service life, the yield of refractory bricks, and the stability of the gasification process. Therefore, developing an efficient and durable anti-wear structure for the coal inlet is one of the key technologies to ensure the long-term safe and efficient operation of the circulating fluidized bed gasifier.

[0003] In the prior art, Chinese utility model patent CN220103171U, entitled "Coal Chute Anti-wear Device," provides a typical anti-wear solution. This device utilizes a two-stage coal feeding pipeline, a coal chuting device, and an upwardly angled air outlet. It uses airflow to blow large pieces of coal that fail to pass screening towards a crash barrier, where they are broken up through impact. This solution, to some extent, buffers the falling speed of the coal pieces and attempts to reduce their size through impact crushing, thereby reducing direct wear on the refractory bricks and the coal chute.

[0004] However, after in-depth analysis, the existing technical solution has the following significant defects and limitations, which restrict its actual wear-resistant effect and overall performance: 1. The crushing mechanism is crude and inefficient: its anti-collision plate surface is usually flat or has a simple arc-shaped structure. When coal blocks collide, the impact force is dispersed over a large area, making it impossible to form an effective stress concentration. Large coal blocks often need to undergo multiple bounces and repeated collisions to achieve a certain degree of crushing, which not only results in low crushing efficiency and high energy consumption, but also easily produces a large amount of insufficiently crushed medium-sized coal blocks, affecting the uniformity of subsequent combustion and gasification efficiency.

[0005] 2. Reliance on strong airflow presents both energy consumption and wear issues: To guide and crush coal blocks, this scheme heavily relies on strong airflow from the outlet. This not only increases the system's power consumption, but the high-speed airflow may also carry coal dust or broken coal, causing additional erosion and wear on other parts of the device (such as the inner wall of the pipes and the side opposite the outlet), creating new wear points.

[0006] 3. Insufficient structural wear resistance and maintainability: As the main impact-bearing component, the crash barrier is mostly a monolithic flat plate structure. Under long-term high-speed impact from large pieces of coal, it is highly susceptible to overall deformation, severe surface wear, and even cracking. Complete replacement is costly and inconvenient to maintain. If the material is not optimized for high-impact, high-wear conditions, its service life will be further shortened.

[0007] 4. Uncontrollable crushing effect and poor particle size uniformity: Relying solely on simple impact crushing lacks active guidance and control over the coal crushing process. The crushed coal has a wide particle size distribution and uneven size, which may lead to incomplete combustion in some areas of the kiln or uneven airflow distribution, affecting the overall process stability.

[0008] In summary, while existing anti-wear devices at the coal chute incorporate buffering and crushing principles, their core crushing unit (anti-collision plate) design suffers from fundamental deficiencies. This results in low crushing efficiency, high energy consumption, easily damaged components, and difficult maintenance. Furthermore, the final crushing effect fails to meet the fuel particle size requirements of efficient gasification processes. Therefore, a novel anti-wear structure for the coal chute is urgently needed, capable of achieving efficient, low-consumption, and controllable crushing, while also possessing excellent wear resistance and convenient maintenance.

[0009] Against this backdrop, this utility model aims to fundamentally improve the design concept of the anti-collision plate, upgrading the traditional "surface contact impact" to a composite crushing mechanism of "point contact penetration + guided shearing" to solve the aforementioned long-standing technical problems and significantly improve the comprehensive performance and reliability of the anti-wear structure at the coal inlet of the circulating fluidized bed gasifier. Utility Model Content

[0010] The purpose of this utility model is to address the shortcomings of existing technologies by proposing an anti-wear structure for the coal inlet of a circulating fluidized bed gasifier.

[0011] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a wear-resistant structure for the coal inlet of a circulating fluidized bed gasifier, comprising two coal feeding pipes, which are staggered along the vertical direction. A first anti-collision plate is installed at the bottom of the upper coal feeding pipe, and a second anti-collision plate is installed at the top of the other coal feeding pipe. Multiple coal crushing cones are installed on the surface of both the first and second anti-collision plates, and multiple guide shearing blocks are installed along the arc surface of each coal crushing cone.

[0012] Preferably, an installation block is installed at one end of the coal crushing cone, and a threaded block is installed at one end of the installation block. Multiple screw holes are opened on the surfaces of the second anti-collision plate and the first anti-collision plate, and the threaded block is threadedly installed in the screw holes.

[0013] Preferably, the top of the guide shear block is inclined at an angle of 40°-60°.

[0014] Preferably, both of the coal delivery pipes have fine material outlets and coarse material outlets on their surfaces.

[0015] Preferably, one end of each of the two coal conveying pipes is provided with an installation port, and a perforated plate is installed in the installation port. The surface of the first anti-collision plate is provided with a ventilation opening that communicates with the installation port.

[0016] Preferably, the mounting block, threaded block, coal crushing cone, and guide shearing block are alloy steel components integrally welded together.

[0017] Preferably, it also includes a fire-resistant insulation plate disposed at the bottom of the two coal delivery pipes.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. Significantly Improved Crushing Efficiency and Particle Size Control: By setting multiple coal crushing cones with guide shear blocks on the first and second anti-collision plates, the traditional "surface contact dispersion impact" of planar anti-collision plates is transformed into a composite crushing mechanism combining "cone tip point contact penetration" and "inclined plane guide shearing." The coal block is first subjected to concentrated stress at the cone tip, resulting in cracks, and then effectively split by multiple 45° inclined guide shear blocks under inertia. This process achieves multi-stage crushing of the coal block in a single impact, greatly improving the single-stage crushing efficiency and producing more uniform fine particles, which is beneficial to improving the combustion efficiency and stability of the kiln.

[0019] 2. Enhanced Wear Resistance and Service Life: The core crushing unit (coal crushing cone, guide shear block) and connecting parts are integrally welded from alloy steel, possessing excellent hardness, toughness, and high-temperature resistance, enabling them to withstand the high-speed impact and wear of coal blocks for extended periods. Simultaneously, the detachable modular design (threaded block and threaded hole connection) allows for independent and rapid replacement of individual coal crushing cones after severe wear, eliminating the need to replace the entire anti-collision plate, significantly reducing maintenance costs and time, and extending the overall structural service life.

[0020] 3. More rational energy utilization and optimized system energy consumption: This invention retains the concept of airflow-assisted screening and crushing, but by setting up a perforated plate and connecting it to a vent, the incoming airflow can be diffused evenly and gently, rather than being strongly directionally injected. This effectively blows up large pieces of coal and guides them to the crushing cone, while avoiding unnecessary secondary scouring and wear on the inner wall of the pipe caused by high-speed airflow, reducing the excessive demand on the fan head and air volume, thereby optimizing system energy consumption.

[0021] 4. More Comprehensive Wear Protection: By setting up a two-stage staggered coal feeding pipeline and anti-collision plates, combined with pre-screening at the fine and coarse material outlets, the coal lumps are graded. Most small coal particles fall directly, medium-sized particles undergo primary crushing, and only the largest lumps undergo the most thorough composite crushing. This grading process reduces continuous and severe impacts on the coal inlet, kiln walls, and refractory bricks, achieving systematic wear protection from source to end.

[0022] 5. High structural integration and strong applicability: This utility model integrates crushing, guiding, screening, airflow distribution, and heat insulation functions into a compact structure. The refractory insulation plate at the bottom of the coal feeding pipeline provides additional thermal protection. The overall structural design is reasonable and easy to modify and install at the coal inlet of existing circulating fluidized bed gasifiers, demonstrating good versatility and promotional value.

[0023] In summary, this utility model, through its innovative composite crushing structure of "coal crushing cone + guide shear block", fundamentally overcomes the shortcomings of existing technologies, such as low crushing efficiency, easy component damage, and high energy consumption, and provides a comprehensive solution for wear prevention at the coal chute that is efficient, wear-resistant, easy to maintain, and energy-saving. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of this utility model installed in the kiln wall; Figure 2 This is a schematic diagram of the connection structure between the coal delivery pipeline and the first anti-collision plate of this utility model; Figure 3 This is a schematic diagram of the connection structure between the first anti-collision plate and the coal crushing cone of this utility model; Figure 4 This is a schematic diagram of the connection structure between the coal crushing cone and the guide shear block of this utility model; Figure 5 This is a schematic diagram of the second anti-collision plate structure of this utility model.

[0025] In the diagram: 1. Kiln wall; 2. Coal feeding pipe; 3. First anti-collision plate; 4. Coal crushing cone; 5. Second anti-collision plate; 6. Coarse material outlet; 7. Perforated plate; 8. Fine material outlet; 9. Screw hole; 10. Mounting block; 11. Ventilation opening; 12. Threaded block; 13. Guide shear block. Detailed Implementation

[0026] 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. Example 1

[0027] like Figures 1 to 5 As shown in the figure, this embodiment provides an anti-wear structure for the coal inlet of a circulating fluidized bed gasifier. This structure is mainly installed at the coal inlet position of the kiln wall 1 of the circulating fluidized bed gasifier. Its core function is to efficiently crush and control the particle size of the falling coal, thereby protecting the coal inlet, kiln wall and internal refractory materials from impact wear.

[0028] The structure mainly consists of two vertically staggered coal feeding pipes 2. The upper coal feeding pipe 2 is fixed to the kiln wall 1 by flanges or welding, and a first anti-collision plate 3, arranged horizontally (or slightly downwardly inclined), is welded to the bottom of its outlet end. The lower coal feeding pipe 2 is also fixed to the kiln wall 1, but a second anti-collision plate 5 is welded to the top of its inlet end. The two anti-collision plates are spatially opposite each other, forming an impact and crushing zone for falling coal. At the bottom of the two coal feeding pipes 2, refractory insulation boards made of materials such as ceramic fiber are usually laid to isolate the high temperature inside the furnace.

[0029] In one key improvement, multiple coal-crushing cones 4 are evenly distributed on the surfaces of the first and second anti-collision plates 3 and 5 facing the coal block falling channel. These coal-crushing cones 4 are conical in shape, with their tips pointing vertically in the direction of the incoming coal block. To further enhance the crushing effect, multiple guide shear blocks 13 are welded at equal intervals along their generatrix on the conical sidewall of each coal-crushing cone 4. Figure 4 As shown, the top of the guide shear block 13 is machined into an inclined surface, which forms a sharp shearing edge at a 45° angle to the horizontal plane. When a large piece of coal impacts the tip of the coal crushing cone 4 and is initially pierced, the fragments slide down the cone surface under inertia and are immediately subjected to effective lateral shearing and splitting by the inclined surfaces of these 45° guide shear blocks 13, thereby achieving a composite crushing process of "piercing-shearing" and significantly improving the thoroughness of single-stage crushing.

[0030] To ensure wear resistance and ease of maintenance, the coal crushing cone 4 is detachably installed. Specifically, a columnar mounting block 10 is welded to the bottom of the coal crushing cone 4, and a threaded block 12 is welded to the end of the mounting block 10. Correspondingly, threaded holes 9 matching the threaded block 12 are pre-machined on the surfaces of the first anti-collision plate 3 and the second anti-collision plate 5. During installation, simply screw the threaded block 12 into the corresponding threaded hole 9 and tighten it. The entire assembly (including the coal crushing cone 4, guide shear block 13, mounting block 10, and threaded block 12) is preferably integrally cast or welded from wear-resistant materials such as high-chromium alloy steel to withstand long-term high-intensity impact and wear. When a coal crushing cone 4 is excessively worn, it can be unscrewed and replaced individually without disassembling or replacing the entire anti-collision plate, resulting in low maintenance costs and convenient operation.

[0031] In the structural design of the coal conveying pipe 2, its sidewalls are sequentially equipped with a fine material outlet 8 and a coarse material outlet 6 along the coal flow direction. The fine material outlet 8 is located near the upstream end, with a smaller opening size, allowing coal powder and fine particles to be discharged in advance under the influence of coal flow disturbance and gravity, falling directly into the furnace. The coarse material outlet 6 is located slightly downstream, with a larger opening size, allowing medium-sized coal lumps to pass through. After two stages of screening, the remaining oversized coal lumps will continue to descend along the pipe and enter the crushing zone formed by the anti-collision plates.

[0032] To assist in coal crushing and reduce energy consumption, this embodiment includes an airflow distribution system at the end of the coal feeding pipe 2 (near the first anti-collision plate 3). Specifically, an installation port is provided at this end of the coal feeding pipe 2, and a perforated plate 7 is embedded within the installation port. The perforated plate 7 is densely covered with tiny ventilation holes. Simultaneously, a vent 11 is provided on the first anti-collision plate 3 at a position corresponding to the installation port. When gas (such as air or circulating flue gas) at a certain pressure is introduced from the outside, the gas is first dispersed into multiple uniform and gentle airflows through the perforated plate 7, and then blown into the coal falling channel through the vent 11. This uniform airflow mainly serves three purposes: first, it blows suspended coal powder deeper into the furnace, preventing it from accumulating at the coal falling port; second, it helps to lift large pieces of coal, making it easier for them to collide with the coal crushing cone 4; and third, the energy of the airflow itself is dispersed, avoiding concentrated scouring and wear on the inner walls of the pipe and the anti-collision plate.

[0033] Working principle:

[0034] Coal lumps are fed from upstream equipment into the upper coal feeding pipe 2. During the descent, fine coal powder is discharged first through the fine material outlet 8, while medium-sized coal lumps are discharged through the coarse material outlet 6. The remaining large coal lumps and some medium-sized coal lumps continue to fall, where they are agitated and lifted by the uniform airflow blown from the ventilation opening 11 at the end of the pipe, and impact the coal crushing cone 4 array of the first anti-collision plate 3 at a certain speed. The coal lumps are first pierced and broken by the cone tips, and then the fragments are further sheared and crushed by the inclined surface of the cones and the guide shear blocks 13. The size of the crushed coal lumps is significantly reduced, and they either fall directly or impact the coal crushing cone 4 of the lower second anti-collision plate 5 during the descent, undergoing secondary crushing. Finally, all coal lumps enter the gasification furnace with smaller and relatively uniform particle sizes, which greatly reduces the impact wear on the coal inlet and the furnace lining, and is conducive to stable and efficient combustion. Example 2

[0035] This embodiment is basically the same as embodiment one, except that: to further enhance the overall rigidity of the anti-collision plate and its ability to defend against extremely large coal pieces, the thickness of the first anti-collision plate 3 and the second anti-collision plate 5 can be increased, or reinforcing ribs can be welded to their backs. At the same time, the arrangement density of the coal crushing cones 4 can be adjusted according to the common size of the coal fed into the furnace. For coal types with large lumps and high hardness, a denser array arrangement can be adopted. Example 3

[0036] This embodiment is basically the same as the first embodiment, except that the tilt angle of the guide shear block 13 can be optimized between 40° and 60° according to the physical properties of the coal (such as hardness and brittleness) to achieve the best shearing and crushing effect.

[0037] 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 wear-resistant structure for the coal inlet of a circulating fluidized bed gasifier, comprising two coal feeding pipes (2), the two coal feeding pipes (2) being staggered along the vertical direction, a first anti-collision plate (3) being installed at the bottom of the upper coal feeding pipe (2), and a second anti-collision plate (5) being installed at the top of the other coal feeding pipe (2), characterized in that, Multiple coal crushing cones (4) are installed on the surfaces of the first anti-collision plate (3) and the second anti-collision plate (5), and multiple guide shearing blocks (13) are installed along the arc surface of the coal crushing cones (4).

2. The anti-wear structure at the coal inlet of a circulating fluidized bed gasifier according to claim 1, characterized in that, One end of the coal crushing cone (4) is equipped with an installation block (10), and one end of the installation block (10) is equipped with a threaded block (12). The surfaces of the second anti-collision plate (5) and the first anti-collision plate (3) are provided with multiple screw holes, and the threaded block (12) is threadedly installed in the screw hole.

3. The anti-wear structure at the coal inlet of a circulating fluidized bed gasifier according to claim 1, characterized in that, The top of the guide shear block (13) is inclined at an angle of 40°-60°.

4. The anti-wear structure at the coal inlet of a circulating fluidized bed gasifier according to claim 1, characterized in that, Both of the coal delivery pipes (2) have fine material outlets (8) and coarse material outlets (6) on their surfaces.

5. The anti-wear structure at the coal inlet of a circulating fluidized bed gasifier according to claim 1, characterized in that, An installation port is provided at one end of each of the two coal conveying pipes (2), and a perforated plate (7) is installed in the installation port. A ventilation opening (11) communicating with the installation port is provided on the surface of the first anti-collision plate (3).

6. The anti-wear structure at the coal inlet of a circulating fluidized bed gasifier according to claim 2, characterized in that, The mounting block (10), threaded block (12), coal crushing cone (4) and guide shear block (13) are alloy steel components formed by integral welding.

7. The anti-wear structure at the coal inlet of a circulating fluidized bed gasifier according to claim 1, characterized in that, It also includes fire-resistant insulation plates installed at the bottom of the two coal delivery pipes (2).

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