A slag falling pipe structure of an anti-coking circulating fluidized bed boiler

Abstract

The utility model relates to a kind of anti-coking circulating fluidized bed boiler's slag chute structure, it relates to the field of boiler technology.The utility model is to solve the problem that the slag chute of existing fluidized bed boiler is blocked due to the uneven air distribution in local area, which leads to slag accumulation and coking.The utility model comprises a slag chute, a sleeve and a cover plate, the sleeve is coaxially arranged outside the slag chute, the sleeve and the slag chute are fixedly connected by the cover plate, a plurality of air holes are uniformly distributed on the upper part of the sleeve wall in the circumferential direction, and each air hole is arranged along the radial direction of the sleeve.The utility model is used for anti-coking circulating fluidized bed boiler.

Description

Technical Field

[0001] This utility model relates to the field of boiler technology, specifically to a slag discharge pipe structure for an anti-coking circulating fluidized bed boiler. Background Technology

[0002] Circulating fluidized bed combustion is a clean coal combustion technology with wide fuel adaptability, a wide load adjustment ratio, and high combustion efficiency. Circulating fluidized bed boilers can control the generation of sulfur dioxide and nitrogen oxides at low cost during combustion, which is of great value to my country's coal-dominated energy structure. With the continuous increase in total coal consumption and growing environmental pressure, the development of circulating fluidized bed boiler technology has become an inevitable trend in order to resolve the contradiction between energy and environmental protection.

[0003] However, the ash discharge pipes of circulating fluidized bed boilers are prone to ash accumulation and coking due to uneven local air distribution, which can lead to pipe blockage. In existing technologies, ash discharge pipes typically employ a simple straight pipe structure, with air distribution relying on the main air chamber, resulting in insufficient air velocity at the bottom of the pipe. Some solutions have attempted to add air caps or enlarge air holes, but these have failed to solve the problem of dynamic balance between airflow distribution and ash content, and still suffer from frequent maintenance and unstable operation. Utility Model Content

[0004] In order to solve the problem of slag accumulation and coking in the slag discharge pipe of existing fluidized bed boilers due to uneven local air distribution, which leads to pipe blockage, this utility model proposes a slag discharge pipe structure for anti-coking circulating fluidized bed boilers.

[0005] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows:

[0006] A slag discharge pipe structure for an anti-coking circulating fluidized bed boiler includes a slag discharge pipe, a sleeve, and a cover plate. The sleeve is coaxially arranged on the outside of the slag discharge pipe, and the sleeve and the slag discharge pipe are fixedly connected by the cover plate. Multiple air holes are evenly distributed along the circumferential direction on the upper part of the sleeve wall, and each air hole is arranged along the radial direction of the sleeve.

[0007] Furthermore, the air vents are inclined downwards from the inside out, with an inclination angle of α.

[0008] Furthermore, the angle of α is 12°~15°.

[0009] Furthermore, the lowest point of the outer end of the vent is level with the lowest point of the vent hole.

[0010] Furthermore, the number of air vents is 12.

[0011] Furthermore, the cover plate is a circular ring plate, with the outer edge of the cover plate fixedly connected to the upper end face of the sleeve, and the inner edge of the cover plate fixedly connected to the upper end face of the slag discharge pipe.

[0012] Furthermore, multiple reinforcing blocks are evenly distributed and fixed between the casing and the slag discharge pipe along the circumferential direction.

[0013] Furthermore, the reinforcing block is located within the area of ​​the boiler air chamber castable refractory layer.

[0014] Furthermore, the number of reinforcement blocks is 4 to 8.

[0015] Furthermore, the outer circumferential sidewall of the sleeve is fixedly connected to the air distribution plate of the boiler air chamber, the lower end of the sleeve extends below the castable layer of the boiler air chamber, and the outer sidewall of the lower end of the sleeve is fixedly connected to the membrane wall fins.

[0016] The beneficial effects of this utility model compared with the prior art are:

[0017] This invention analyzes the phenomenon of uneven flow on the air distribution plate, involving multiple factors such as fuel particle size and coal conveying air arrangement. Therefore, it provides a ash discharge pipe device to prevent ash slag from coking and clogging, thereby improving the continuity of boiler operation.

[0018] This utility model's slag discharge pipe structure features uniform air distribution, avoiding material deposition or dead zones caused by insufficient airflow in local areas, maintaining the continuous fluidization state of the bed material, reducing the scouring and wear of the pipe wall or air cap caused by high-speed airflow due to uneven air distribution, and also helping to achieve uniform bed temperature distribution, reducing coking caused by uneven bed temperature, and ensuring the safe and stable operation of the boiler. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0020] Figure 2 yes Figure 1 A top-down view;

[0021] Figure 3 yes Figure 1 A diagram showing the view from below;

[0022] Figure 4 This is an installation diagram of this utility model. Detailed Implementation

[0023] Specific implementation method one: Combining Figures 1 to 4 This embodiment describes a slag discharge pipe structure for an anti-coking circulating fluidized bed boiler, comprising a slag discharge pipe 1, a sleeve 2, and a cover plate 4. The sleeve 2 is coaxially disposed on the outside of the slag discharge pipe 1, and the sleeve 2 and the slag discharge pipe 1 are fixedly connected by the cover plate 4. Multiple air holes 5 are evenly distributed along the circumferential direction on the upper part of the sleeve 2 wall, and each air hole 5 is disposed along the radial direction of the sleeve 2.

[0024] In this embodiment, a sleeve 2 is fitted on the outside of the slag discharge pipe 1, and an air hole 5 is opened on the sleeve 2 to introduce an appropriate amount of fluidizing air, so that the fuel particles around the slag discharge pipe are disturbed by the airflow and form a fluidized state of fluidized bed (i.e., the state of particle suspension and flow), avoiding ash and slag accumulation and agglomeration, thereby achieving uniform flow and discharge.

[0025] Specific Implementation Method Two: Combining Figures 1 to 4 In this embodiment, the air vent 5 is inclined downwards from the inside out at an angle of α. Other components and connections are the same as in specific embodiment one.

[0026] This design prevents bed material from flowing back into the return air chamber.

[0027] Specific implementation method three: Combining Figures 1 to 4 In this embodiment, the angle of α is 12°~15°. Other components and connections are the same as in specific embodiment two.

[0028] The airflow ejected from the downward-sloping vent will generate an oblique impact force, making it easier to penetrate the dense phase material layer at the bottom of the furnace, intensifying the collision and mixing between particles, avoiding local material accumulation, and improving fluidization uniformity.

[0029] The downward tilt angle is controlled within the range of 12 to 15 degrees. The airflow direction is conducive to carrying up fine particles, reducing the risk of large particles depositing and slagging near the wind cap, and also reducing the risk of material clogging the wind eye.

[0030] Specific implementation method four: Combination Figures 1 to 4 In this embodiment, the lowest point of the outer end of the vent 5 is flush with the lowest point of the vent hole. Other components and connections are the same as in specific embodiment three.

[0031] This setup ensures uniform distribution of fluidizing air within the furnace, preventing problems such as localized coking and poor fluidization caused by uneven air distribution.

[0032] Specific Implementation Method Five: Combining Figures 1 to 4 This embodiment describes a configuration where there are 12 air vents 5. Other components and connection methods are the same as in specific embodiments one, two, three, or four.

[0033] Specific Implementation Method Six: Combination Figures 1 to 4 In this embodiment, the cover plate 4 is an annular plate. The outer edge of the cover plate 4 is fixedly connected to the upper end face of the sleeve 2, and the inner edge of the cover plate 4 is fixedly connected to the upper end face of the slag discharge pipe 1. Other components and connection methods are the same as in specific embodiment one.

[0034] In this embodiment, the cover plate 4 is welded to the sleeve 2 and the slag discharge pipe 1.

[0035] The cover plate 4 is installed at the upper end of the sleeve 2 and the slag discharge pipe 1, which can enhance the strength of the slag discharge pipe 1 and prevent its upper end from deforming.

[0036] Specific implementation method seven: Combining Figures 1 to 4 In this embodiment, multiple reinforcing blocks 3 are evenly distributed and fixed between the sleeve 2 and the slag discharge pipe 1 along the circumferential direction. Other components and connection methods are the same as in specific embodiment one.

[0037] This design enhances the support strength between the casing 2 and the slag discharge pipe 1, thereby improving overall stability.

[0038] In this embodiment, the reinforcing block 3 is welded to both the sleeve 2 and the slag discharge pipe 1.

[0039] Specific implementation method eight: Combination Figures 1 to 4 This embodiment describes a reinforcing block 3 located within the area of ​​the boiler air chamber castable refractory layer. Other components and connection methods are the same as in specific embodiment seven.

[0040] Specific Implementation Method Nine: Combining Figures 1 to 4 This embodiment describes a configuration where the number of reinforcing blocks 3 is 4 to 8. Other components and connection methods are the same as in specific embodiment seven.

[0041] Specific Implementation Method Ten: Combining Figures 1 to 4 In this embodiment, the outer circumferential sidewall of the sleeve 2 is fixedly connected to the air distribution plate of the boiler air chamber. The lower end of the sleeve 2 extends below the castable refractory layer of the boiler air chamber, and the outer sidewall of the lower end of the sleeve 2 is fixedly connected to the membrane wall fins. Other components and connection methods are the same as in specific embodiment one.

[0042] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0043] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0044] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A slag discharge pipe structure for an anti-coking circulating fluidized bed boiler, characterized in that: It includes a slag discharge pipe (1), a sleeve (2) and a cover plate (4). The sleeve (2) is coaxially arranged on the outside of the slag discharge pipe (1). The sleeve (2) and the slag discharge pipe (1) are fixedly connected by the cover plate (4). Multiple air holes (5) are evenly distributed along the circumferential direction on the upper part of the sleeve (2). Each air hole (5) is arranged along the radial direction of the sleeve (2).

2. The slag discharge pipe structure of an anti-coking circulating fluidized bed boiler according to claim 1, characterized in that: The air vent (5) is inclined downward from the inside to the outside with an angle of α.

3. The slag discharge pipe structure of an anti-coking circulating fluidized bed boiler according to claim 2, characterized in that: The angle of α is 12°~15°.

4. The slag discharge pipe structure of an anti-coking circulating fluidized bed boiler according to claim 3, characterized in that: The lowest point of the outer end of the air hole (5) is level with the lowest point of the air cap hole.

5. The slag discharge pipe structure of an anti-coking circulating fluidized bed boiler according to claim 1, 2, 3 or 4, characterized in that: The number of air vents (5) is 12.

6. The slag discharge pipe structure of an anti-coking circulating fluidized bed boiler according to claim 1, characterized in that: The cover plate (4) is a circular ring plate. The outer edge of the cover plate (4) is fixed to the upper end face of the sleeve (2), and the inner edge of the cover plate (4) is fixed to the upper end face of the slag discharge pipe (1).

7. The slag discharge pipe structure of an anti-coking circulating fluidized bed boiler according to claim 1, characterized in that: Multiple reinforcing blocks (3) are evenly distributed and fixed between the casing (2) and the slag discharge pipe (1) along the circumferential direction.

8. The slag discharge pipe structure of an anti-coking circulating fluidized bed boiler according to claim 7, characterized in that: The reinforcing block (3) is located within the area of ​​the boiler air chamber casting material layer.

9. The slag discharge pipe structure of an anti-coking circulating fluidized bed boiler according to claim 7, characterized in that: The number of reinforcing blocks (3) is 4 to 8.

10. The slag discharge pipe structure of an anti-coking circulating fluidized bed boiler according to claim 1, characterized in that: The outer circumferential sidewall of the sleeve (2) is fixedly connected to the air distribution plate of the boiler air chamber. The lower end of the sleeve (2) extends to the bottom of the boiler air chamber casting material layer, and the outer sidewall of the lower end of the sleeve (2) is fixedly connected to the membrane wall fin.

Images