Fire nozzle of rotational flow pulverized coal burner

Abstract

The utility model discloses a swirl pulverized coal burner nozzle which comprises a primary air duct, a flame stabilizing gear ring and an expansion cone, the primary air duct is provided with an axial connecting boss perpendicular to the axis of the primary air duct, the flame stabilizing gear ring is arranged on the connecting boss and located between the primary air duct and the expansion cone, and the expansion cone is connected with the connecting boss through an axial connecting bolt. And the width L of the expansion cone connecting ring of the expansion cone is 30-150mm. According to the utility model, the problem that the nozzle of the burner is inconvenient to overhaul and maintain is solved, the burner can be directly overhauled and maintained in a furnace conveniently, the maintenance cost is reduced, and the problem that the backflow area of the outlet of the burner is difficult to construct is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of burners, and in particular relates to a swirl pulverized coal burner nozzle. Background Art

[0002] As one of the core equipment of the counter-fired pulverized coal boiler, the swirl pulverized coal burner forms a swirling airflow and a flue gas recirculation zone by rationally organizing the air distribution, and draws in high-temperature flue gas to mix strongly with the pulverized coal, so that the pulverized coal can ignite quickly, burn stably, and burn out completely. The outlet airflow of the swirl burner is composed of several rotating and non-rotating airflows combined with each other. If the combustion is organized separately, the nozzle structure of the swirl pulverized coal burner will affect the construction of the burner outlet flow field, thereby affecting the combustion effect. The burner nozzle is equipped with an expansion cone to effectively change the flow direction of the airflow, which plays an important role in organizing the recirculation zone at the nozzle, and effectively ensures the early temperature so that the pulverized coal can ignite in time. The burner nozzle is equipped with a flame-stabilizing tooth to disturb the airflow, so that the air-powder mixture ignites violently and quickly. The primary air duct, flame-stabilizing tooth, and expansion cone are traditionally connected by radial bolts in a sleeve manner, such as Figure 1 As shown in the figure, due to the high temperature at the nozzle and the scouring of the pulverized coal airflow, the flame stabilizing teeth often wear and fall off, the flame stabilizing tooth ring is deformed and damaged, and the expansion cone is deformed and cracked, which will seriously affect the combustion effect and threaten the safe operation of the boiler; in addition, this expansion cone structure is difficult to construct the burner outlet recirculation zone, such as Figure 2 As shown; and once the burner nozzle is damaged, it can only be replaced by pulling out the entire burner, which requires high time and space, has a long maintenance cycle and high maintenance costs. Utility Model Content

[0003] In order to solve the above problems, the utility model provides a swirl pulverized coal burner nozzle, which solves the problem of inconvenient inspection and maintenance of the burner nozzle, facilitates direct inspection and maintenance of the burner in the furnace, reduces maintenance costs, and solves the problem of difficulty in constructing a burner outlet recirculation zone.

[0004] The embodiments of the present invention are implemented by the following technical solutions:

[0005] A swirl pulverized coal burner nozzle comprises a primary air duct, a flame stabilizing tooth ring and an expansion cone. The primary air duct is provided with an axial connecting boss perpendicular to the axis of the primary air duct. The flame stabilizing tooth ring is arranged on the connecting boss and is located between the primary air duct and the expansion cone. The expansion cone is connected to the connecting boss by an axial connecting bolt, wherein the expansion cone connecting ring width L of the expansion cone is 30-150mm.

[0006] In one embodiment of the utility model, the primary air cylinder includes a straight cylinder section and a conical cylinder section, and the conical cylinder section is trumpet-shaped.

[0007] In one embodiment of the present invention, the angle α of the inclined surface of the cone section is 5-25°.

[0008] In one embodiment of the present invention, the flame-stabilizing tooth ring includes at least three flame-stabilizing tooth lobes.

[0009] In one embodiment of the utility model, the expansion cone connecting ring of the expansion cone is provided with a plurality of second flame-stabilizing teeth, and the second flame-stabilizing teeth correspond one-to-one to the first flame-stabilizing teeth of the flame-stabilizing tooth ring.

[0010] In one embodiment of the utility model, a cushion material is filled between the primary air cylinder and the expansion cone.

[0011] The technical solution of the utility model has at least the following advantages and beneficial effects:

[0012] The utility model realizes the axial connection between the primary air duct and the expansion cone through the axial connecting bolts, solves the problem of inconvenient inspection and maintenance of the burner nozzle, facilitates the direct inspection and maintenance of the burner in the furnace, reduces the maintenance cost, and sets the expansion cone connecting ring width L of the expansion cone to 30-150mm, realizes the construction of a "wide annular" recirculation zone, and solves the problem of the difficulty in constructing the recirculation zone at the burner outlet. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 The structure of the burner nozzle in the prior art;

[0015] Figure 2 It is a schematic diagram of the burner outlet recirculation area in the prior art;

[0016] Figure 3 A half-section schematic diagram of a burner nozzle in the utility model;

[0017] Figure 4 It is a half-section schematic diagram of a primary air duct in the utility model;

[0018] Figure 5 It is a schematic diagram of the flame stabilizing tooth ring in the utility model;

[0019] Figure 6 It is a schematic diagram of the expansion cone in the utility model;

[0020] Figure 7 It is a schematic diagram of the wide recirculation zone at the burner outlet in the utility model.

[0021] Icons: 1. Primary air duct; 1-1. Straight tube section; 1-2. Conical tube section; 1-3. Axial connecting boss; 2. Flame-stabilizing tooth ring; 2-1. First flame-stabilizing tooth; 3. Expanding cone; 3-1. Expanding cone cylinder; 3-2. Expanding cone connecting ring; 3-3. Second flame-stabilizing tooth; 4. Axial connecting bolt. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0025] In the description of the present utility model, it should be noted that if the terms "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the utility model product is usually placed when used. It is only for the convenience of describing the present utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present utility model.

[0026] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "configure", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Example

[0028] Please refer to Figure 1-7The present embodiment provides a swirl pulverized coal burner nozzle, which includes a primary air cylinder 1, a flame stabilizing tooth ring 2 and an expansion cone 3. The primary air cylinder 1 includes a straight cylinder section 1-1 and a conical cylinder section 1-2. The conical cylinder section 1-2 is trumpet-shaped, and the angle α of the inclined surface of the conical cylinder section 1-2 is 5-25°. The conical cylinder section 1-2 serves as a transition section between the straight cylinder section 1-1 and the expansion cone 3 and plays a guiding role. This conical cylinder section 1-2 increases the peripheral area of ​​the pulverized coal airflow outlet and guides the pulverized coal airflow into a "wide annular" recirculation zone, thereby strengthening the contact between the high-temperature flue gas and the pulverized coal in the early stage, and strengthening the ignition stability and the NOx "in-flame" reduction.

[0029] The primary air duct 1 is also provided with an axial connection boss 1-3 at the tail of the cone section 1-2, and the axial connection boss 1-3 is perpendicular to the axis of the primary air duct 1, and the width h of the axial connection boss 1-3 is 30-200mm. The axial connection boss 1-3 at the tail end of the cone can effectively isolate the primary air from the secondary air, prevent premature mixing, and avoid adverse effects such as increased primary air volume, reduced flame temperature, and unstable ignition. At the same time, 6-24 through holes are evenly opened axially on the axial connection boss 1-3 to cooperate with the flame stabilizing tooth ring 2 and the expansion cone 3. It should be noted that the primary air duct 1 is integrally formed of wear-resistant materials, including but not limited to cast steel and other materials.

[0030] In the present embodiment, the flame-stabilizing tooth ring 2 is arranged on the connecting boss and is located between the primary air duct 1 and the expansion cone 3. The flame-stabilizing tooth ring 2 includes at least three flame-stabilizing tooth lobes, which are assembled into a ring structure. Each flame-stabilizing tooth lobe is provided with a first flame-stabilizing tooth 2-1. Through holes are evenly opened along the circumference of the flame-stabilizing tooth ring 2 and matched with the primary air duct 1 and the expansion cone 3. It should be noted that the flame-stabilizing tooth ring 2 is made of wear-resistant material, including but not limited to silicon carbide and other materials.

[0031] In this embodiment, the expansion cone 3 includes an expansion cone 3 connecting ring, an expansion cone 3 cone cylinder and a plurality of second flame stabilizing teeth 3-3. The angle β of the expansion cone 3 cone cylinder is 5-45°. The expansion cone 3 connecting ring is provided with a plurality of through holes matching the primary air duct 1 and the flame stabilizing tooth ring 2. In addition, the primary air duct 1, the flame stabilizing tooth ring 2 and the expansion cone 3 connecting ring are connected by the axial connecting bolt 4 in this embodiment, thus realizing the axial connection between the primary air duct 1, the flame stabilizing tooth ring 2 and the expansion cone 3. When repairing the burner, the axial connecting bolt 4 can be removed in the furnace for repair and maintenance, thus solving the problem of inconvenient inspection and maintenance of the burner nozzle, facilitating direct inspection and maintenance of the burner in the furnace, and reducing the maintenance cost. It should be noted that a cushioning material, such as high-temperature glue, is filled between the primary air duct 1 and the expansion cone 3. The expansion cone 3 can be formed in one piece and then an expansion joint is opened or formed in pieces according to the material. The expansion cone 3 is made of heat-resistant material, including but not limited to cast steel and other materials.

[0032] In this embodiment, the width L of the expansion cone 3 connecting ring and the expansion cone 3 can work together to build a "wide annular" recirculation zone at the burner outlet, further allowing the flue gas to reflux and heat the coal powder airflow, thereby strengthening ignition stability and NOx "in-flame" reduction. The width L of the expansion cone 3 connecting ring is 30-150 mm and matches the width h of the connecting boss. The expansion cone 3 connecting ring of the expansion cone 3 is also provided with a plurality of second flame stabilizing teeth 3-3, which correspond one-to-one to the first flame stabilizing teeth 2-1 of the flame stabilizing tooth ring 2. When the primary air duct 1, the flame stabilizing tooth ring 2 and the expansion cone 3 are installed, the first flame stabilizing tooth 2-1 of the flame stabilizing tooth ring 2 and the second flame stabilizing tooth 3-3 of the expansion cone 3 are back to back, increasing the thickness of the flame stabilizing teeth, further strengthening the disturbance of the airflow, and at the same time increasing the thickness of the flame stabilizing teeth, further improving reliability.

[0033] The utility model realizes the axial connection between the primary air duct 1 and the expansion cone 3 through the axial connecting bolt 4, solves the problem of inconvenient inspection and maintenance of the burner nozzle, facilitates the direct inspection and maintenance of the burner in the furnace, reduces the maintenance cost, and sets the width L of the expansion cone 3 connecting ring of the expansion cone 3 to 30-150mm, realizes the construction of a "wide annular" recirculation zone, and solves the problem of the difficulty in constructing the recirculation zone at the burner outlet.

[0034] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. Swirl pulverized coal burner nozzle, characterized in that: It includes a primary air duct, a flame-stabilizing tooth ring and an expansion cone. The primary air duct is provided with an axial connecting boss perpendicular to the axis of the primary air duct. The flame-stabilizing tooth ring is arranged on the connecting boss and is located between the primary air duct and the expansion cone. The expansion cone is connected to the connecting boss by an axial connecting bolt, wherein the expansion cone connecting ring width L of the expansion cone is 30-150mm.

2. The swirl pulverized coal burner nozzle according to claim 1, characterized in that: The primary air cylinder comprises a straight cylinder section and a conical cylinder section, and the conical cylinder section is trumpet-shaped.

3. The swirl pulverized coal burner nozzle according to claim 2, characterized in that: The angle α of the inclined surface of the cone section is 5-25°.

4. The swirl pulverized coal burner nozzle according to claim 1, characterized in that: The flame stabilizing tooth ring includes at least three flame stabilizing tooth lobes.

5. The swirl pulverized coal burner nozzle according to claim 1, characterized in that: The expansion cone connecting ring of the expansion cone is provided with a plurality of second flame-stabilizing teeth, and the second flame-stabilizing teeth correspond one to one with the first flame-stabilizing teeth of the flame-stabilizing tooth ring.

6. The swirl pulverized coal burner nozzle according to claim 1, characterized in that: A cushion material is filled between the primary air cylinder and the expansion cone.

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