Boiler coal feeding flow-aiding smoke locking device

Abstract

The utility model discloses a coal feeding flow-aiding smoke locking device for a boiler, which comprises a coal inlet pipe, a middle pipe and a coal outlet pipe through which coal flow passes, and an air shaping device through which flow-aiding air entering from a flow-aiding air pipe passes in sequence. The central axes of the coal inlet pipe and the coal outlet pipe coincide, and the bottom opening of the middle pipe is slightly smaller than the upper opening. The shaping air device comprises a flow-assisting air pipe, an air bellow and a plurality of flow-guiding air pipes, the flow-assisting air pipe is vertically or tangentially communicated with the air bellow, the air bellow is fixed outside the middle pipe, the flow-guiding air pipes are positioned below the air bellow and uniformly distributed on the outer wall of the middle pipe, upper openings of the flow-guiding air pipes are communicated with an inner cavity of the air bellow, and bottom openings of the flow-guiding air pipes are uniformly distributed on the periphery of the coal outlet pipe. According to the utility model, the horizontal flow aiding air entering from the flow aiding air pipe is changed into the same direction as the coal flow after passing through the air bellow and the flow guide air pipe, and forms a common downward resultant force with the coal flow, so that hot air flowing upwards from the inside of the boiler can be effectively inhibited, and the coal feeder is protected.

Description

Technical Field

[0001] This utility model relates to the field of boiler coal feeding technology, specifically to a boiler coal feeding flow aid and smoke-locking device. Background Technology

[0002] During power generation in a power plant, coal is conveyed from the coal bunker to the CFB boiler or pulverized coal furnace via a coal feeder for combustion. Since the coal feeder chute is connected to the boiler furnace, to prevent hot air from flowing back into the feeder and damaging the conveyor belt and other components inside the feeder, a primary cold air supply is typically connected at the coal inlet. This cold air flows downwards with the coal to suppress the rising hot air. However, the pressure of the primary cold air decreases after passing through the feeder's cavity, and its force weakens further after passing through the chute below the feeder (both the feeder outlet and the lower chute are larger than the inlet). Therefore, its effect in suppressing hot air is often poor, sometimes resulting in the cold air failing to suppress the hot air, leading to damage to the feeder's conveyor belt. To solve this problem, a technology has emerged on the market to introduce an additional air supply for auxiliary hot air suppression, complementing the primary air supply from the feeder. For example, the Chinese patent with announcement number "CN 209819575 U" and title "A kind of annular sealing air device" uses a secondary air intake device to introduce secondary air and then transforms it into spiral air intake to prevent the backflow of boiler flue gas and hot air. The shortcomings of this technology are: (1) After the air entering the inverted conical cavity through the air intake device, it is shaped into a spiral wind. When the spiral wind runs downward in the chute, its force is decomposed into a vertically downward component and a component acting on the chute wall, resulting in insufficient vertical downward force to suppress hot air; (2) Since the spiral wind is generated by the inverted conical cavity structure, the spiral wind gradually contracts in the chute until the cone point of the inverted conical cavity. During this process, it is a lateral interference to the vertically downward coal flow, which can easily push the coal in the coal flow to hit the inner wall of the chute laterally, causing coal accumulation on the inner wall; and the wind direction after the cone point becomes a turbulent flow, and its downward wind force is not easy to suppress the upward hot air. Utility Model Content

[0003] In order to overcome the defects in the existing technology, this utility model discloses a boiler coal feeding aid and smoke-locking device, which turns the aid air into a downward direct airflow that is in the same direction as the coal flow, and can effectively suppress the upward hot air.

[0004] The technical solution adopted by this utility model is: a boiler coal feeding aid and smoke-locking device, including a coal inlet pipe, an intermediate pipe and a coal outlet pipe that are sequentially passed through and fixedly connected by the coal flow, and a shaping air device through which the aid air passes; the shaping air device includes an aid air pipe, a wind box and multiple guide air pipes, the wind box is fixedly installed on the upper outer periphery of the intermediate pipe, the multiple guide air pipes are located below the wind box and are evenly distributed on the outer periphery of the intermediate pipe, the upper opening of the guide air pipe communicates with the inner cavity of the wind box, and the bottom openings are evenly distributed on the outer periphery of the coal outlet pipe; the outer wall surface of the coal outlet pipe is parallel to the coal flow direction; one end of the aid air pipe is connected to the aid air, and the other end communicates with the inner cavity of the wind box.

[0005] As a further improvement of this utility model, the intermediate tube is a circular tube with a bottom diameter to top diameter ratio of 0.8:1-0.9:1.

[0006] As a further improvement of this utility model, the coal inlet pipe and the coal outlet pipe are circular pipes with their central axes coinciding.

[0007] As a further improvement of this utility model, the wind box has a cylindrical structure, and the airflow aid duct is perpendicularly or tangentially connected to the wall of the wind box.

[0008] As a further improvement of this utility model, the number of the air guide ducts is 6-8.

[0009] As a further improvement of this utility model, the upper opening area of ​​the guide duct is more than twice the lower opening area.

[0010] As a further improvement of this utility model, it also includes an upper flange and a lower flange, wherein the upper flange is disposed on the outer side of the upper opening of the coal inlet pipe and the lower flange is disposed on the outer side of the bottom opening of the guide air duct.

[0011] Compared with the prior art, the present invention has the following technical effects:

[0012] (1) After the auxiliary air enters the wind box, it is distributed to each guide air duct. The guide air duct goes down along the outer wall of the middle pipe. After being constrained by the vertical outer wall of the coal outlet pipe at the outlet, it is in the same direction as the coal flow. One of the air in the coal flow is in the same direction as the auxiliary air and is directly opposite to the hot air rising from the boiler. Its force to suppress the hot air will be more direct and stronger. Therefore, the effect of suppressing the hot air is also better.

[0013] (2) The upper opening of the guide duct is larger than the lower opening. After the airflow reaches the lower opening through the upper opening, the air pressure increases and the air force becomes stronger.

[0014] (3) The airflow descends along the inner wall of the chute, which can prevent coal accumulation on the inner wall of the chute, or the airflow can remove the coal accumulation on the inner wall of the chute after coal has accumulated. Attached Figure Description

[0015] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] Figure 1 This is a three-dimensional structural schematic diagram (I) of the boiler coal feeding and flow-assisted smoke-locking device of this utility model;

[0017] Figure 2 This is a three-dimensional structural schematic diagram (II) of the boiler coal feeding and flow-assisted smoke-locking device of this utility model;

[0018] Figure 3 This is a three-dimensional structural schematic diagram (III) of the boiler coal feeding and flow-assisted smoke-locking device of this utility model;

[0019] Figure 4 This is a three-dimensional structural cross-sectional view of the boiler coal feeding and flow-assisted smoke-locking device of this utility model;

[0020] Figure 5 yes Figure 4 Front view;

[0021] In the diagram, 1-coal inlet pipe, 2-intermediate pipe, 3-coal outlet pipe, 4-flow aid duct, 5-air box, 6-flow guide duct, 7-upper flange, 8-lower flange. Detailed Implementation

[0022] This utility model relates to a boiler coal feeding aid and smoke-locking device, suitable for power plants or coal-fired power generation enterprises. It is installed below the coal feeder outlet. The coal feeder outlet connects to the boiler via a long chute to deliver coal into the boiler. This device connects between the coal feeder outlet and the upper opening of the long chute, or alternatively, by dividing the long chute into two sections and connecting between the two sections, with the connection point close to the coal feeder outlet. Typically, a single air supply is connected at the coal feeder inlet end. This air supply flows downwards with the coal flow to suppress the rising hot air inside the boiler. This air supply originates from the power plant's primary cooling air system.

[0023] like Figure 1-4As shown, this device includes a coal inlet pipe 1, an intermediate pipe 2, a coal outlet pipe 3, an auxiliary air duct 4, an air box 5, and guide air ducts 6. The coal inlet pipe 1 is welded to the intermediate pipe 2, and the intermediate pipe 2 is welded to the coal outlet pipe 3. The vertical coal flow enters the upper opening of the coal inlet pipe 1 after coming down from the coal feeder outlet, then passes sequentially through the intermediate pipe 2 and the coal outlet pipe 3, and finally enters the chute leading to the boiler. The coal inlet pipe 1 and the coal outlet pipe 3 are straight cylindrical pipes with their central axes coinciding. During installation, the coal inlet pipe 1 and the coal outlet pipe 3 are placed vertically, meaning the outer wall of the coal outlet pipe is parallel to the vertical coal flow. The intermediate pipe 2 is an inverted conical cylindrical pipe, with the bottom diameter slightly smaller than the top diameter, with a diameter ratio of 0.8:1 to 0.9:1. The air box 5 is located on the outer periphery of the intermediate pipe 2, and eight guide air ducts 6 are evenly distributed on the outer periphery of the intermediate pipe 2, located below the air box. Specifically, the bellows 5 is a cylindrical, sealed structure, and its inner cavity is not connected to the inner cavity of the intermediate pipe 2. The upper opening of the guide duct 6 is connected to the bottom surface of the bellows 5, and the lower opening is evenly distributed on the outer wall of the coal outlet pipe 3. The upper and lower openings of the guide duct 6 are basically rectangular in shape, and the line connecting the center points of the upper and lower openings is on the same plane as the central axis of the intermediate pipe 2. Furthermore, the area of ​​the upper opening of the guide duct 6 is more than twice the area of ​​the lower opening.

[0024] The device also includes an upper flange 7 and a lower flange 8, wherein the upper flange 7 is used to connect with the coal chute flange at the coal outlet of the coal feeder, and the lower flange 8 is used to connect with the chute flange below.

[0025] like Figure 4 and Figure 5 As shown, the bottom opening of intermediate pipe 2 is slightly recessed to facilitate communication between the bottom opening of the guide duct 6 and the chute below it, thus adapting to the original dimensions of the power plant chute. The small inward recess of the bottom opening of intermediate pipe 2, meaning that the bottom diameter is slightly smaller than the top diameter, will not affect the flow of coal or cause coal accumulation on the inner wall of intermediate pipe 2.

[0026] The flow-aiding duct 4 is used to connect the flow-aiding air. The flow-aiding duct 4 is connected perpendicularly or tangentially to the wall of the air box 5. When connected perpendicularly, the flow-aiding duct 4 enters from the middle of the wall of the air box 5, and the connection port is flared. The function of the air box 5 is to adjust the direction of the flow-aiding air (lateral horizontal wind) and convert it into a downward direct current through the flow-guiding duct 6.

[0027] During operation, both the primary air supply from the coal feeder and the auxiliary air supply to this unit are drawn from the boiler's primary cooling air system. After exiting the coal feeder, the coal flow and primary air supply vertically enter the inlet pipe 1, intermediate pipe 2, and outlet pipe 3 before flowing into the lower chute. The auxiliary air supply pipe 4 is horizontally connected to the auxiliary air supply. The auxiliary air supply enters the air box 5 and then flows into eight guide air pipes 6. The air in the guide air pipes 6 flows downwards simultaneously; because the upper opening is larger than the bottom opening, the air pressure flowing out through the bottom opening is stronger. The outlet pipe 3 is placed vertically, its outer wall serving as a vertical guide surface to vertically guide the outgoing air. The air then flows vertically downwards along with the coal flow and primary air supply, directly facing the rising hot air from the boiler. The combined force of the primary air supply, auxiliary air supply, and coal flow effectively suppresses the rising hot air. Since the wind generated by this device has no component force, the combined force generated by it, the primary air, and the coal flow will be greater and more direct than that of existing technologies, resulting in a better heat suppression effect.

[0028] In this embodiment, the pressure of the auxiliary airflow is greater than the pressure of the primary airflow inside the coal feeder. This means the airflow inside the coal feeder is relatively weak with lower pressure, while the auxiliary airflow is strong with higher pressure. The weaker airflow inside the coal feeder reduces the continuous impact of the primary airflow on the feeder's components and also removes accumulated coal and dust from the feeder's cavity, protecting the feeder's switches, sensors, and weighing components, thus improving the overall service life of the coal feeder.

[0029] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes that can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention are within the protection scope of the claims of the present invention.

Claims

1. A boiler coal feeding flow aid and smoke-locking device, characterized in that, It includes a coal inlet pipe (1), an intermediate pipe (2), and a coal outlet pipe (3) that are sequentially passed through and fixedly connected by the coal flow, as well as a shaping air device through which the flow-aiding air passes; the shaping air device includes a flow-aiding air pipe (4), an air box (5), and multiple flow-guiding air pipes (6). The air box (5) is fixedly installed on the upper outer periphery of the intermediate pipe (2). The multiple flow-guiding air pipes (6) are located below the air box (5) and are evenly distributed on the outer periphery of the intermediate pipe (2). The upper opening of the flow-guiding air pipe (6) is connected to the inner cavity of the air box (5), and the bottom opening is evenly distributed on the outer periphery of the coal outlet pipe (3). The outer wall surface of the coal outlet pipe (3) is parallel to the coal flow direction. One end of the flow-aiding air pipe (4) is connected to the flow-aiding air, and the other end is connected to the inner cavity of the air box (5).

2. The boiler coal feeding and flue gas blocking device according to claim 1, characterized in that, The intermediate tube (2) is a circular tube with a bottom diameter to top diameter ratio of 0.8:1-0.9:

1.

3. The boiler coal feeding and flue gas blocking device according to claim 1, characterized in that, Both the coal inlet pipe (1) and the coal outlet pipe (3) are circular pipes, and their central axes coincide.

4. The boiler coal feeding and flue gas blocking device according to claim 1, characterized in that, The air box (5) has a cylindrical structure, and the airflow aid duct (4) is perpendicularly or tangentially connected to the wall of the air box (5).

5. The boiler coal feeding and flue gas blocking device according to claim 1, characterized in that, The number of the air ducts (6) is 6-8.

6. The boiler coal feeding and flue gas blocking device according to claim 1, characterized in that, The opening area of ​​the upper part of the guide duct (6) is more than twice the opening area of ​​the lower part.

7. The boiler coal feeding and flue gas blocking device according to claim 1, characterized in that, It also includes an upper flange (7) and a lower flange (8), wherein the upper flange (7) is located on the outer side of the upper opening of the coal inlet pipe (1), and the lower flange (8) is located on the outer side of the bottom opening of the guide air pipe (6).

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