Guiding horizontally-arranged pulverized coal distributor

Abstract

The utility model relates to the technical field of pulverized coal distributors, in particular to a horizontally-arranged pulverized coal distributor capable of guiding. The outlet end of the inlet elbow is connected with a connecting pipe, the outlet end of the connecting pipe is connected with a transition pipe, the outlet end of the transition pipe is connected with a diffusion pipe, two outlets are symmetrically formed in the diffusion pipe and connected with outlet pipes respectively, and a guide plate is arranged at the position, close to one side of the connecting pipe, of the back arc inside the inlet elbow. Flow guide shutters are symmetrically arranged on the two sides of the interior of the diffusion pipe, and a pulverized coal separation mechanism is arranged in the connecting pipe. Segregation caused by steering is adjusted by the guide plate, and pulverized coal is mixed; the pulverized coal is mixed and stirred again through the separation mechanism; the resistance of the outlets on the two sides and the amount of pulverized coal are adjusted by adjusting the inclination angle of the flow guide louver, an air-pulverized coal mixture carrying the pulverized coal flows through the pulverized coal inlet and enters the distributor, the flow guide louver plays a role in flow equalization, the resistance of outlet pipelines is balanced, and finally the purpose of evenly distributing the air-pulverized coal mixture of the outlets on the two sides is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of coal powder distributors, in particular to a guideable horizontally arranged coal powder distributor. Background Art

[0002] In a thermal power plant using coal as raw material, the main power equipment is coal-fired boilers. The economic operation of pulverized coal boilers greatly affects the economic benefits, social benefits and safety and reliability of production of power companies. The dual-adjustable pulverized coal distributor is one of the key equipment in the combustion and pulverizing system of a thermal power plant. It is responsible for rationally organizing boiler combustion and effectively controlling the temperature field in the furnace. By adjusting the dual-adjustable pulverized coal distributor, the uniform distribution of pulverized coal and air can be achieved. The pulverized coal flow and air flow of each branch can be adjusted separately without interfering with each other. Ensure that the combustion power of each burner is equal and the ignition conditions are the same.

[0003] Most of the boilers of ultra-supercritical 1000MW units adopt direct-blowing pulverizing systems. Usually, each coal mill needs to provide primary air to 4 or even 8 burners on a certain burner layer of the boiler. Improving the uniformity of primary air distribution in direct-blowing pulverizing systems has received increasing attention. Article 8.1 of the power industry standard "Design Standards and Calculation Methods for Pulverizing System Equipment in Thermal Power Plants" (DL / T5154) stipulates that "for medium-speed mill direct-blowing pulverizing systems, coal powder and air between each primary air duct of the same layer of burners should be evenly distributed, and the air volume deviation should not exceed ±8%, and the coal powder deviation should not exceed ±10%." The current dual-adjustable coal powder distributors are fixed and adjustable. Fixed coal powder distributors have good wear resistance, but poor adjustment ability. The air volume deviation of those with good adjustment performance is 20% to 30%, and the air volume deviation of those with poor adjustment performance is 40% to 50%. Adjustable coal powder distributors have higher adjustment accuracy and a deviation of more than ±15%, but poor wear resistance and short service life. It seriously affects the ignition of the primary air at the burner outlet and the combustion conditions of the entire furnace, causing problems such as flame deflection, large steam temperature deviation, and even boiler tube burst. At the same time, due to the high flow rate of the primary air, the wear on the dual-adjustable pulverized coal distributor is relatively serious, causing the equipment design performance to decline or fail, affecting the safe and stable operation of the boiler system. The dual-adjustable pulverized coal distributor is often equipped with a steering elbow at the inlet. Due to the inertia of the medium flow, the steering elbow causes more fuel distribution in the back arc part, causing the fuel entering the dual-adjustable pulverized coal distributor to be segregated. Utility Model Content

[0004] The utility model aims to solve the above problems, thereby providing a guideable horizontally arranged coal powder distributor which can prevent fuel from segregation.

[0005] The utility model solves the above problems and adopts the following technical solutions:

[0006] A steerable horizontally arranged pulverized coal distributor comprises an inlet elbow, the outlet end of the inlet elbow is connected to a connecting pipe, the outlet end of the connecting pipe is connected to a transition pipe, the outlet end of the transition pipe is connected to a diffuser, two outlets are symmetrically arranged on the diffuser and are respectively connected to the outlet pipes, a guide plate is arranged at the back arc inside the inlet elbow and close to one side of the connecting pipe, guide louvers are symmetrically arranged on both sides of the diffuser, and a pulverized coal separation mechanism is arranged in the connecting pipe.

[0007] Compared with the prior art, the utility model adopting the above technical solution has the following outstanding features:

[0008] The coal powder is turned through the inlet elbow, and the guide plate adjusts the segregation caused by the turning for the first time, and the coal powder is mixed; the coal powder is mixed and stirred again through the coal powder separation mechanism; by adjusting the inclination angle of the guide louver, the outlet resistance and coal powder amount on both sides are adjusted, and the air-powder mixture carrying coal powder flows through the coal powder inlet into the distributor. The guide louver plays the role of equalizing the flow, balancing the resistance of the outlet pipe, and finally achieving the purpose of uniform distribution of the air-powder mixture at the outlets on both sides.

[0009] As a preferred embodiment, a further technical solution of the utility model is:

[0010] Furthermore, the coal powder separation mechanism includes a columnar bluff body located in the connecting pipe, a plurality of guide blades are arranged circumferentially and inclinedly on the outer periphery of the middle part of the bluff body, the guide blades are fixed to the inner wall of the connecting pipe, and both ends of the bluff body are conical.

[0011] Further, the diameter of the connecting pipe is three to four times the diameter of the middle portion of the bluff body.

[0012] Furthermore, ceramic bushings are arranged on the inner walls of the inlet elbow, the connecting pipe, the transition pipe, the diffuser pipe and the outlet pipe.

[0013] Furthermore, the guide plate is rotatably connected in the inlet elbow via a pin shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of a cross-sectional structure of an embodiment of the utility model from top view;

[0015] Figure 2 This is a schematic diagram of the main cross-sectional structure of an embodiment of the utility model;

[0016] Figure 3 This is a top view of a half-section structure of a connecting pipe according to an embodiment of the utility model;

[0017] Figure 4 This is a schematic diagram of the main structure of the connecting pipe of an embodiment of the utility model;

[0018] Marked in the figure are: inlet elbow 1, connecting pipe 2, transition pipe 3, diffuser 4, outlet pipe 5, guide plate 6, guide louver 7, blunt body 8, guide vane 9. DETAILED DESCRIPTION

[0019] The present invention is further described below in conjunction with embodiments, the purpose of which is only to provide a better understanding of the content of the present invention. Therefore, the examples given do not limit the protection scope of the present invention.

[0020] A steerable horizontally arranged pulverized coal distributor comprises an inlet elbow 1, the outlet end of the inlet elbow 1 is connected to a connecting pipe 2, the outlet end of the connecting pipe 2 is connected to a transition pipe 3, the outlet end of the transition pipe 3 is connected to a diffuser 4, two outlets are symmetrically arranged on the diffuser 4 and are respectively connected to outlet pipes 5, a guide plate 6 is arranged at the back arc inside the inlet elbow 1 and close to one side of the connecting pipe 2, the angle of the guide plate 6 is adjustable, guide louvers 7 are symmetrically arranged on both sides inside the diffuser 4, the guide louvers 7 are made of silicon carbide ceramics, the angle of the guide louvers 7 is adjustable, and a pulverized coal separation mechanism is arranged in the connecting pipe 2.

[0021] Furthermore, the coal powder separation mechanism includes a columnar bluff body 8 located in the connecting pipe 2, and a plurality of guide blades 9 are arranged along the circumferential inclination of the outer periphery of the middle part of the bluff body 8, and the guide blades 9 are fixed to the inner wall of the connecting pipe 2. Both ends of the bluff body 8 are conical. When the coal powder passes through the cone on the front side of the bluff body 8, the coal powder is mixed again. When the coal powder passes through the guide blades 9, the coal powder is stirred and mixed for the third time to prevent the coal powder from segregation, and the flow is guided through the cone on the rear side to divert the dense phase and cross the dilute phase. The bluff body 8 and the guide blades 9 are made of silicon carbide ceramics.

[0022] Furthermore, the diameter of the connecting pipe 2 is three to four times the diameter of the middle portion of the bluff body 8 .

[0023] Furthermore, ceramic bushings are arranged on the inner walls of the inlet elbow 1, the connecting pipe 2, the transition pipe 3, the diffuser pipe 4 and the outlet pipe 5, and the ceramic bushings increase the wear resistance.

[0024] Furthermore, the guide plate is rotatably connected in the inlet elbow through a pin shaft, and the angle of the guide plate is adjusted by rotating the pin shaft on the outside. The guide plate and the pin shaft are made of silicon carbide ceramics.

[0025] The coal powder is turned through the inlet elbow 1, and the guide plate 6 adjusts the segregation caused by the turning for the first time, and the coal powder is mixed; the coal powder is mixed and stirred again through the coal powder separation mechanism; by adjusting the inclination angle of the guide louver 7, the outlet resistance and the amount of coal powder on both sides are adjusted, and the air-powder mixture carrying coal powder flows through the coal powder inlet into the distributor. The guide louver 7 plays a role in equalizing the flow, balancing the resistance of the outlet pipe, and finally achieving the purpose of uniform distribution of the air-powder mixture at the outlets on both sides.

[0026] The above description is only a preferred feasible embodiment of the present utility model, and does not limit the scope of rights of the present utility model. All equivalent changes made using the contents of the present utility model specification and its drawings are included in the scope of rights of the present utility model.

Claims

1. A steerable horizontally arranged pulverized coal distributor, comprising an inlet elbow, the outlet end of the inlet elbow is connected to a connecting pipe, the outlet end of the connecting pipe is connected to a transition pipe, the outlet end of the transition pipe is connected to a diffuser, the diffuser is symmetrically provided with two outlets and respectively connected to outlet pipes, characterized in that: A guide plate is arranged at the back arc inside the inlet elbow and close to one side of the connecting pipe, flow guide shutters are symmetrically arranged on both sides inside the diffuser, and a coal powder separation mechanism is arranged in the connecting pipe.

2. The steerable horizontally arranged pulverized coal distributor according to claim 1, characterized in that: The coal powder separation mechanism includes a columnar bluff body located in the connecting pipe, a plurality of guide blades are arranged circumferentially and inclinedly on the outer periphery of the middle part of the bluff body, the guide blades are fixed to the inner wall of the connecting pipe, and both ends of the bluff body are conical.

3. The steerable horizontally arranged pulverized coal distributor according to claim 2, characterized in that: The diameter of the connecting tube is three to four times the diameter of the middle part of the bluff body.

4. The steerable horizontally arranged pulverized coal distributor according to claim 1, characterized in that: Ceramic bushings are arranged on the inner walls of the inlet elbow, the connecting pipe, the transition pipe, the diffuser pipe and the outlet pipe.

5. The steerable horizontally arranged pulverized coal distributor according to claim 1, characterized in that: The guide plate is rotatably connected in the inlet elbow through a pin shaft.

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