CN209655348U - A built-in energy-saving pulverized coal distribution device - Google Patents

Abstract

A built-in energy-saving pulverized coal distribution device, including a louver-type baffle door with an adjustable angle. A fixed frame is provided, and several blades are arranged on the fixed frame, and several blades are connected with the actuator; several blades are located under each pulverized coal outlet pipe or between adjacent pulverized coal outlet pipes, and several blades are arranged horizontally, axially arrangement or circumferential arrangement. By adjusting the angle of the blades, changing the opening of the baffle door, and independently adjusting the air powder volume at the inlet of a single pulverized coal pipeline, the deviation of the air powder volume of each pulverized coal pipeline is reduced to meet the requirement of uniform distribution.

Description

A built-in energy-saving pulverized coal distribution device

technical field

The utility model belongs to special equipment for a boiler pulverizing system, in particular to a built-in energy-saving pulverized coal distribution device.

Background technique

Most modern large-capacity boilers use a direct-blowing pulverization system. After the pulverized coal is screened by the coal mill separator, it is powered by the primary air and sent directly to each pulverized coal pipeline. After reaching the pulverized coal burner, it is sprayed into the furnace for combustion. . The length of each pulverized coal pipeline to the burner is different, the number of elbows used along the way is different, and the difference in processing and installation will cause the resistance of the primary air along the way to be different, resulting in the difference in the primary wind speed and air volume of each pulverized coal pipeline. , resulting in uneven distribution of air powder.

The uneven distribution of air powder among the burners will directly affect the ignition and stable combustion of the pulverized coal flow at the outlet of the burner, resulting in deflection of the flame, washing of the furnace wall, deviation of the heat load and steam temperature of the furnace, increase of _NOx emissions, and It may cause the accumulation of coal powder in the horizontal pipeline, resulting in pipe blockage and burnout of the corresponding burner, and even cause local reducing atmosphere to cause local coking and high-temperature corrosion on the heating surface, which will lead to accidents such as over-temperature pipe explosion and seriously affect the operation of the unit safety and economy.

Article 7.10.1 of my country's electric power industry standard "Technical Regulations for Design and Calculation of Pulverizing System in Thermal Power Plants" (DL/T5145-2012) points out that in order to ensure uniform distribution of air powder in parallel powder conveying pipelines, direct-blown pulverizing in large-capacity boilers Some type of pulverized coal distributor must be installed in the system. According to the thermal test data, the deviation of air powder volume in the outlet powder pipe of a single pulverizer in a power plant can reach about 30% to 40%. At present, power plants generally adjust the shrinkage cavity openings at the inlet and outlet of each powder pipe multiple times to control the resistance of each powder pipe along the process, so as to achieve the purpose of wind speed leveling at one time. The disadvantage of this method is that the operation is complicated and the resistance loss is large. In the adjustment process of this method, it is necessary to adjust the apertures of multiple shrinkage cavities repeatedly, and it takes a long time to complete one adjustment and the workload is heavy. Moreover, the inherent characteristic of shrinkage cavity is that it causes a large loss of primary wind resistance and poor economy.

Utility model content

In order to overcome the defects of large workload, complicated operation and large primary air loss in the existing technology of adjusting the amount of air powder through the opening of the shrinkage hole, the purpose of this utility model is to provide a built-in energy-saving pulverized coal distribution device , by directly adjusting the opening of the baffle at the entrance of each pulverized coal pipeline or between the entrances, the air powder volume between each pulverized coal pipeline can be flexibly controlled, and the effect of reducing the deviation of the air powder volume can be achieved with a small resistance loss.

In order to achieve the above object, the utility model adopts the following technical solutions:

A built-in energy-saving pulverized coal distribution device, including a louver-type baffle door with adjustable angle. A fixed frame is provided, and several blades are arranged on the fixed frame, and the several blades are all connected with the actuator.

The further improvement of the utility model lies in that the actuator is connected with the link mechanism, and the link mechanism is connected with the blades.

The further improvement of the utility model is that several blades are located under each pulverized coal outlet pipe or between adjacent pulverized coal outlet pipes.

The further improvement of the utility model lies in that several blades are arranged horizontally, axially or circumferentially.

A further improvement of the utility model is that the blades are connected to the fixed frame through the rotating shaft.

A further improvement of the utility model is that the blades are arranged horizontally below the inlet of each pulverized coal outlet pipeline; or the blades are arranged horizontally or axially between the inlets of adjacent pulverized coal outlet pipelines; Pipes are arranged circumferentially below the inlet of each pulverized coal outlet pipe.

The further improvement of the utility model is that when several blades are arranged horizontally or axially, it is called a tiled baffle door; the tiled baffle door adopts a single-layer or multi-layer structure, and each layer includes a single or multiple blades; When a single-layer multi-blade structure is adopted, each blade is arranged parallel to each other or in a V-shaped arrangement with each other, and the angle of the blades is adjusted through the actuator and the linkage mechanism to realize the opening and closing of the flat baffle door; In the multi-layer structure, the blades of the first layer are parallel to each other, and the blades of the second layer are V-shaped; or the blades of the first layer are parallel to each other, and the blades of the second layer are parallel to each other.

The further improvement of the utility model is that when several blades are arranged circumferentially, it is called a cylindrical baffle door; for a cylindrical baffle door, a single-layer or multi-layer structure is adopted, and each layer includes a single or multiple blades; Each blade of each layer is arranged in a cylindrical shape along the circumference of a certain diameter, and each blade forms an acute angle with the central axis of the cylinder. By changing the angle between the blade and the central axis of the cylinder, the opening and closing of the cylindrical baffle door is realized. .

The further improvement of the utility model is that when the combination of the tiled baffle door and the cylindrical baffle door is adopted, the tiled baffle door is arranged below the pulverized coal outlet pipeline, and the cylindrical baffle door It is arranged between the tiled baffle door and the pulverized coal outlet pipe, and the air-powder mixture enters the pulverized coal outlet pipe from the horizontally arranged blades and the circumferentially arranged blades respectively.

The further improvement of the utility model is that the blade is streamlined; the surface of the blade is sprayed with a wear-resistant coating or the surface is hardened.

Compared with the prior art, the beneficial effect of the utility model is that the utility model adopts an angle-adjustable louver-type baffle door, which is arranged at the entrance of each pulverized coal pipeline or between the entrances of adjacent pulverized coal pipelines, The structure is compact, the space occupied is small, and the installation process does not require structural modification of the coal mill; by changing the opening of the louver-type baffle door, the air powder volume at the inlet of a single pulverized coal pipeline is independently adjusted, and the operation is simple and the mutual influence is small , reduce the deviation of the air powder volume of each pulverized coal pipeline, meet the requirement of uniform distribution, and overcome the problem of uneven distribution of air powder volume in the coal pulverized pipeline at the exit of the pulverizer in the prior art.

Further, the blades are streamlined, which can reduce the flow resistance of the air-powder mixture.

Furthermore, the working environment of the blade is relatively harsh, and it is directly in contact with the air powder mixture with solid particles and a high flow rate. In order to improve its service life and prevent rapid wear, the blade is made of wear-resistant materials or the surface is sprayed with wear-resistant coating or surface Hardened.

Description of drawings

Fig. 1 is the schematic diagram of embodiment 1 of the present utility model;

Fig. 2 is a schematic diagram along line A-A in Fig. 1;

Fig. 3 is the schematic diagram of embodiment 2 of the present utility model;

Fig. 4 is the schematic diagram of embodiment 3 of the present utility model;

Fig. 5 is a sectional view along line A-A in Fig. 4;

Fig. 6 is the schematic diagram of embodiment 4 of the present utility model;

Fig. 7 is the schematic diagram of embodiment 5 of the present utility model;

Fig. 8 is the schematic diagram of embodiment 6 of the present utility model;

Fig. 9 is a sectional view along line A-A in Fig. 8;

In the figure, 1 is a separator, 2 is an upper shell, 3 is a settling chamber, 4 is a coal drop pipe, 5 is a pulverized coal outlet pipe, 6 is a blade, 7 is a fixed frame, and 8 is an actuator.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is further described.

Referring to Fig. 1, the upper part of the coal mill is arranged with a coal drop pipe 4 and an upper casing 2, a separator 1 is arranged inside the upper casing 2, a settling chamber 3 is arranged on the top of the upper casing 2, and a number of pulverized coal is arranged on the top of the settling chamber 3 The outlet pipe 5 and the bottom end of the coal drop pipe 4 pass through the settling chamber 3 and extend into the upper shell 2 inside.

The utility model provides a built-in energy-saving pulverized coal distribution device, which includes a louver-type baffle door, which is composed of a fixed frame 7 , an actuator 8 and a plurality of blades 6 . The louver type baffle door is arranged in the settling chamber 3 of the coal mill. Specifically, a fixed frame 7 is arranged in the settling chamber 3 of the coal mill, and several blades 6 are arranged on the fixed frame 7, and several blades 6 are connected with the actuator 8 connected. The top of the settling chamber 3 is provided with several pulverized coal outlet pipes 5;

The blade 6 is connected to the fixed frame 7 through a rotating shaft.

The actuator 8 is connected with the link mechanism, and the link mechanism is connected with the blade 6, and the link mechanism can adjust the angle of the blade 6.

Several blades 6 are arranged horizontally or axially, or several blades 6 are arranged circumferentially;

Specifically, there are three layout types for the louvered baffle door, which are: (1) horizontally arranged below the entrance of each pulverized coal outlet pipe; (2) arranged horizontally or along the axial direction of the pulverized coal outlet (3) arranged below the inlet of each pulverized coal outlet pipe along the circumference of the pulverized coal outlet pipe.

When several blades 6 are arranged horizontally or axially, it is called a tiled baffle door; when several blades 6 are arranged circumferentially, it is called a cylindrical baffle door. Several blades 6 are located below each pulverized coal outlet pipe 5 or between adjacent pulverized coal outlet pipes 5 . The arrangement method and arrangement position of the blades 6 can be flexibly selected according to the actual situation, including but not limited to one arrangement method or one arrangement position.

For tiled baffle doors, a single-layer or multi-layer (greater than or equal to 2 layers) structure can be used, and each layer can have single or multiple blades, and the blades are parallel to each other or at a certain angle. When a single-layer multi-blade structure is adopted, each blade 6 is arranged parallel to each other or in a "V" shape, connected to the fixed frame 7 through a rotating shaft, and coordinated with a transmission mechanism (ie, a linkage mechanism) by an actuator 8 The angle of the blade 6 can be adjusted to realize the opening and closing of the baffle door. When the double-layer multi-blade structure is adopted, the first layer of blades and the second layer of blades can be arranged in different combinations, for example: the first layer of blades are parallel to each other, and the second layer of blades are in a "V" shape; The blades of the first layer are parallel to each other, and the blades of the second layer are parallel to each other.

For cylindrical baffle doors, single-layer or multi-layer structures can be used, and each layer can have single or multiple blades. Each blade 6 of each layer is arranged in a cylindrical shape along the circumference of a certain diameter, and each blade forms a certain angle with the central axis of the cylinder, and the angle between it and the central axis of the cylinder can be changed by rotation to realize the opening of the baffle door. combine.

The number of horizontally or axially arranged louver-type baffle door blades is 1-8, the shape is streamlined, and the wear-resistant materials are used or the blade surfaces are sprayed with wear-resistant materials.

The number of louver-type baffle door blades arranged in the circumferential direction is 1 to 40 pieces, the shape is streamlined, and the wear-resistant material is used or the surface of the blade is sprayed with wear-resistant material.

When the combination of tiled baffle door and cylindrical baffle door is adopted, the tiled baffle door is placed under the pulverized coal outlet pipeline 5, and the cylindrical baffle door is placed under the tiled baffle Between the door and the pulverized coal outlet pipe 5, the air-powder mixture enters the pulverized coal outlet pipe 5 from the blades 6 arranged horizontally at the bottom and the blades 6 arranged circumferentially on the side.

The frame of the louver type baffle door is made of integral molding or section steel. Each blade is fixed in the baffle frame 7 through a rotating shaft, and each rotating shaft is connected through a linkage mechanism. The adjustment of the blade angle depends on the actuator to drive the blade to rotate through the linkage mechanism. The driving mode of the actuator 8 can be electric or pneumatic. or electrohydraulic.

The blade 6 is streamlined, which can reduce the flow resistance of the air-powder mixture. The working environment of the blade 6 is relatively harsh, and it is directly in contact with the wind powder mixture with solid particles and a high flow rate. Hardened.

Example 1

Referring to Fig. 1 and Fig. 2, a tiled baffle door is adopted, with a double-layer multi-blade structure, and the blades 6 are arranged below the pulverized coal outlet pipe 5, and the blades 6 of each layer are parallel to each other, and the first layer of blades and the second layer There is a certain angle between the layer blades. After the air-powder mixture is separated by the separator 1 set in the upper casing 2, the qualified coal powder spirally rises into the settling chamber 3, and after being diffused and depressurized in the settling chamber 3, the air-powder mixture tends to be uniform, and passes through the first and second stages respectively. One deck of blades and the second layer of blades enter the pulverized coal outlet pipeline 5 again. When the first layer of blades and the second layer of blades are placed in the vertical position, the tiled baffle door is in the fully open position, and the amount of air powder entering the pulverized coal outlet pipe 5 is the largest; when the first layer of blades and the second layer of blades When they are all placed in the horizontal position, the tiled baffle door is in the fully closed position, and the amount of air powder entering the pulverized coal outlet pipe 5 is the smallest; when the first layer of blades and the second layer of blades form a "V" When the angle is included, the air-powder mixture flows in along the direction of the first layer of blades, hits the second layer of blades to change direction, forms a swirling airflow and enters the pulverized coal outlet pipe 5, and due to the centrifugal force, the thicker coal powder hits the second layer of blades Finally, it settles under the action of gravity and returns to the grinding area for re-grinding, which plays a certain role in separation. At the same time, due to the reduction of the flow area, the amount of air powder entering the pulverized coal outlet pipe 5 is also reduced. The first layer of blades and the second The smaller the angle between the layer blades, the smaller the flow area and the smaller the amount of wind powder. Therefore, the operating personnel can judge the uniformity of the air powder volume in each primary air duct of the burner according to the conditions such as the load, the combustion status in the furnace, and the primary wind speed in the pulverized coal outlet pipe. The amount of powder is redistributed. The rotation of the blade 6 is realized by the linkage mechanism driven by the actuator 8. The actuator 8 is electric, pneumatic or electro-hydraulic, and the operator can operate on the panel in the centralized control room to realize the control of the baffle door.

Example 2

Referring to Figure 3, a tiled baffle door can be used, with a double-layer multi-blade structure, placed under the pulverized coal outlet pipe 5, and the blades 6 of each layer are parallel to each other, and the first layer of blades and the second layer of blades are parallel to each other .

Example 3

Referring to Fig. 4 and Fig. 5, a combination of a tiled baffle door and a cylindrical baffle door can also be used, with a single-layer multi-blade structure, placed below the pulverized coal outlet pipe 5 . The blades 6 of the tiled baffle door form a certain angle with each other, and the blades 6 of the cylindrical baffle door point to the radial direction when they are fully opened. After the air-powder mixture is separated by the separator 1, the qualified coal powder ascends in a spiral manner and enters the settling chamber 3, and after being diffused and depressurized in the settling chamber 3, the air-powder mixture tends to be uniform. Part of the air-powder mixture enters the pulverized coal outlet pipe 5 from the bottom through the tiled baffle door, and part of the air-powder mixture enters the pulverized coal outlet pipe 5 through the cylindrical baffle door from the side. The angles of the tiled baffle door and the cylindrical baffle door are both adjusted by the actuator 8 through the connecting rod structure. The smaller the angle of the blade 6, the smaller the flow area, and the amount of air powder entering the pulverized coal outlet pipe 5 smaller.

Example 4

Referring to FIG. 6 , a combination of a tiled baffle door and a cylindrical baffle door can be used, with a single-layer multi-blade structure, placed below the pulverized coal outlet pipe 5 . The blades 6 of the tiled baffle door form a certain angle with each other, and the blades 6 of the cylindrical baffle door form a certain angle with the tangential direction when they are fully opened.

Example 5

Referring to Fig. 7, the tiled baffle door can also be placed between adjacent pulverized coal outlet pipes 5, with a double-layer multi-blade structure. The blades 6 of the tiled baffle door form a certain angle with each other and are arranged radially. By adjusting the included angle of the blades 6, by changing the flow area, the amount of air powder entering the area below the pulverized coal outlet pipe 5 from the side is adjusted to achieve the effect of adjusting the amount of air powder entering the pulverized coal outlet pipe 5.

Example 6

Referring to Fig. 8 and Fig. 9, the tiled baffle door can be placed between adjacent pulverized coal outlet pipes 5, with a double-layer multi-blade structure. The blades 6 of the tiled baffle door form a certain angle with each other and are arranged axially.

Claims (10)

1. a kind of built-in type energy saving moulded coal powder distributor, which is characterized in that the louver type damper door including adjustable-angle, Louver type damper door includes fixed frame (7), actuator (8) and several blades (6)；It is provided at the top of expansion chamber (3) several Discharge pipeline (5)；It being provided with fixed frame (7) in expansion chamber (3), several blades (6) are arranged on fixed frame (7), And several blades (6) are connected with actuator (8).

2. a kind of built-in type energy saving moulded coal powder distributor according to claim 1, which is characterized in that actuator (8) with Link mechanism is connected, and link mechanism is connected with blade (6).

3. a kind of built-in type energy saving moulded coal powder distributor according to claim 2, which is characterized in that several blades (6) Below each discharge pipeline (5) or between adjacent discharge pipeline (5).

4. a kind of built-in type energy saving moulded coal powder distributor according to claim 2, which is characterized in that several blades (6) Horizontally disposed, axial arrangement or circumferentially.

5. a kind of built-in type energy saving moulded coal powder distributor according to claim 1, which is characterized in that blade (6) passes through Shaft is connected on fixed frame (7).

6. a kind of built-in type energy saving moulded coal powder distributor according to claim 1, which is characterized in that blade (6) is horizontal It is arranged in below each discharge entrance；Or blade (6) is horizontal or is axially arranged in phase along discharge pipeline (5) Between adjacent discharge entrance；Or blade (6) along discharge pipeline (5) circumferentially in each discharge pipeline Below entrance.

7. a kind of built-in type energy saving moulded coal powder distributor according to claim 6, which is characterized in that when several blades (6) when horizontal or axial arrangement, referred to as flush system baffle door；Flush system baffle door uses single or multi-layer structure, and every layer includes Single or multiple blades；When using single layer multiple leaflet constructs, each blade (6) is parallel between each other or between each other at V-shape Arrangement adjusts the angle of blade (6) by actuator (8) coupler link mechanism, realizes the folding of flush system baffle door；Using double When layer multiple leaflet constructs, first layer blade is parallel to each other, and second layer blade is in V-shaped；Or first layer blade is mutually flat Row, second layer blade are parallel to each other.

8. a kind of built-in type energy saving moulded coal powder distributor according to claim 7, which is characterized in that when several blades (6) circumferentially when, referred to as drum type brake baffle door；For drum type brake baffle door, using single or multi-layer structure, every layer includes single A or multiple blades；Every layer of each blade (6) along a certain diameter circumference at cylindrical shape, each blade and cylinder center axis Line is at an acute angle, by changing the angle of blade (6) and cylinder center's axis, realizes the folding of drum type brake baffle door.

9. a kind of built-in type energy saving moulded coal powder distributor according to claim 8, which is characterized in that kept off using flush system When the arrangement that plate door and drum type brake baffle door combine, flush system baffle door is set to the lower section of discharge pipeline (5), Drum type brake baffle door is set between flush system baffle door and discharge pipeline (5), and wind powder mixture is respectively from horizontally disposed Blade (6) and blade (6) circumferentially enter discharge pipeline (5).

10. a kind of built-in type energy saving moulded coal powder distributor according to claim 1, which is characterized in that blade (6) is stream Line style；Blade (6) surface is coated with abrasion-resistant coatings or surface carries out cure process.