CN212237708U

CN212237708U - Coal pulverizer entry wind channel mixing arrangement

Info

Publication number: CN212237708U
Application number: CN202020458460.XU
Authority: CN
Inventors: 郭艳玲
Original assignee: Northwest Electric Power Research Institute of China Datang Corp Science and Technology Research Institute Co Ltd
Current assignee: Northwest Electric Power Research Institute of China Datang Corp Science and Technology Research Institute Co Ltd
Priority date: 2020-04-01
Filing date: 2020-04-01
Publication date: 2020-12-29
Anticipated expiration: 2030-04-01

Abstract

The utility model relates to a coal fired power plant's coal pulverizer wind technical field that flow equalizes, in particular to coal pulverizer entry wind channel mixing arrangement. Including hot-blast main and cold-blast main, cold-blast main is connected with hot-blast main, and its junction is equipped with mixing arrangement, and mixing arrangement installs in hot-blast main, mixing arrangement includes hot-blast pipe and cold wind pipe, hot-blast pipe is including the hot-blast inner tube, hot-blast well pipe and the hot-blast outer tube that establish of overlapping in proper order, the utility model discloses a mixing arrangement multiplicable cold wind of setting and the exchange rate between the hot-blast to improve cold wind and hot-blast mixing intensity, and improve the layering flow phenomenon, and then improve wind flow measuring device's flow homogeneity, the post-mixing temperature distribution of better.

Description

Coal pulverizer entry wind channel mixing arrangement

Technical Field

The utility model relates to a coal fired power plant's coal pulverizer wind technical field that flow equalizes, in particular to coal pulverizer entry wind channel mixing arrangement.

Background

At present, a differential pressure type flowmeter is usually arranged in a primary air duct at an inlet of a coal mill for measuring air volume of a coal-fired boiler of a power station, although the air volume measuring elements are various in types, a layered wall-sticking flow is generated after an upstream cold and hot air pipeline of an air measuring device is converged, a sharp elbow is also arranged, and a straight pipe section is generally short, so that the flow field in the air duct is disordered, the primary air flow measuring error of the inlet of the coal mill of most power plants is extremely large, the automatic input rate of the air volume is very low, the unreasonable ratio of the air volume at the inlet of the coal mill to the coal entering the boiler can cause that pulverized coal particles cannot be fully combusted, and negative effects are caused on the safe and economic operation of the boiler, so that the improvement.

SUMMERY OF THE UTILITY MODEL

To the problem mentioned among the prior art, the utility model provides a can solve coal pulverizer entry wind channel's cold wind and the inhomogeneous problem of distribution's coal pulverizer entry wind channel after hot-blast the mixing device.

The utility model relates to a coal mill inlet air duct mixing device, which comprises a hot air duct and a cold air duct, wherein the cold air duct is connected with the hot air duct, the joint of the hot air pipeline and the cold air pipeline is provided with a mixing device which is arranged in the hot air pipeline and comprises a hot air conduit and a cold air conduit, the hot air conduit comprises a hot air inner pipe, a hot air middle pipe and a hot air outer pipe which are sequentially sleeved, wherein the two ends of the hot air inner pipe are respectively provided with a first inner layer and a second inner layer, the two ends of the hot air middle pipe are respectively provided with a first middle layer and a second middle layer, the two ends of the hot air outer pipe are respectively provided with a first outer layer and a second outer layer, the first outer layer and the first middle layer are arranged in a closed mode, the first middle layer and the first inner layer are arranged in an open mode, the first inner layer is arranged in a closed mode, a grid is arranged between the second outer layer and the second middle layer, the second middle layer and the second inner layer are arranged in a closed mode, and the second inner layer is arranged in an open mode; the cold air pipeline stretches into the hot air pipeline and extends to the outer wall of the hot air conduit to be vertically connected, wherein one end of the cold air conduit is connected with the cold air pipeline, and the other end of the cold air conduit penetrates through the hot air middle pipe to extend to the outer wall of the hot air inner pipe to be connected.

Preferably, the number of the grids is multiple, and the multiple grids are annularly arranged between the second outer layer and the second middle layer.

Preferably, the size of the mixing device is smaller than the diameter of the hot air duct.

Preferably, the diameter of the cold air inner pipe is smaller than that of the cold air pipeline.

Preferably, the air flow measuring device is arranged in the hot air pipeline.

Preferably, the coal mill is connected with the end, far away from the mixing device, of the hot air pipeline.

Compared with the prior art, the utility model, following technological effect has been gained:

the utility model discloses a mixing arrangement multiplicable cold wind of setting and the exchange rate between the hot-blast to improve cold wind and hot-blast mixing intensity, and improve the layering phenomenon of flowing, and then improve wind flow measurement device's the homogeneity that flows, after the homogeneous mixing temperature distribution better.

Drawings

Fig. 1 is a schematic diagram of the prior art.

Fig. 2 is a schematic view of the overall structure of the present invention.

Fig. 3 is a schematic view of the mixing device of the present invention.

Reference numerals: 1-hot air pipeline; 2-a cold air duct; 3-a wind flow measuring device; 4, a coal mill access port; 5-a mixing device; 6-hot air outer pipe; 7-hot air medium pipe; 8-hot air inner pipe; 9-a second outer layer; 10-a second intermediate layer; 11-a second inner layer; 12-cold air duct.

Detailed Description

Examples

The utility model relates to a coal mill inlet air duct mixing device, as shown in figures 2 and 3, comprising a hot air duct 1 and a cold air duct 2, wherein the cold air duct 2 is connected with the hot air duct 1, a mixing device 5 is arranged at the connection part, the mixing device 5 is arranged in the hot air duct 1, the mixing device 5 comprises a hot air conduit and a cold air conduit 12, the hot air conduit comprises a hot air inner tube 8, a hot air middle tube 7 and a hot air outer tube 6 which are sleeved in sequence, the two ends of the hot air inner tube 8 are respectively a first inner layer and a second inner layer 11, the two ends of the hot air middle tube 7 are respectively a first middle layer and a second middle layer 10, the two ends of the hot air outer tube 6 are respectively a first outer layer and a second outer layer 9, wherein the first outer layer and the first middle layer are arranged in a sealing way, the first middle layer and the first inner layer are arranged in an open way, the first inner layer is arranged in a sealing way, the second middle layer 10 and the second inner layer 11 are arranged in a closed manner, and the second inner layer 11 is arranged in an open manner; the cold air duct 2 extends into the hot air duct 1 and extends to the outer wall of the hot air duct to be vertically connected, wherein one end of the cold air duct 12 is connected with the cold air duct 2, and the other end of the cold air duct passes through the hot air middle pipe 7 and extends to the outer wall of the hot air inner pipe 8 to be connected. The number of the grids is multiple, preferably 10 in the embodiment, and the multiple grids are annularly arranged between the second outer layer 9 and the second middle layer 10. The size of the mixing device 5 is smaller than the diameter of the hot air pipeline 1. The diameter of the cold air duct 12 is smaller than that of the cold air pipeline 2. The air flow measuring device is characterized by further comprising an air flow measuring device 3, wherein the air flow measuring device 3 is arranged in the hot air pipeline 1. The coal pulverizer is characterized by further comprising a coal pulverizer access port 4, wherein the coal pulverizer access port 4 is connected with one end, far away from the mixing device 5, of the hot air pipeline 1.

When the device is used, hot air enters through the hot air pipeline 1, cold air enters through the cold air pipeline 2, when the hot air passes through the mixing device 5, the hot air can be divided into two parts, because the mixing device 5 is smaller than the diameter of the hot air pipeline 1, a part of hot air flows through a gap between the mixing device 5 and the hot air pipeline 1, the other part of hot air can flow through the hot air middle pipe 7, when the cold air passes through the mixing device 5, the cold air also enters into two parts, one part of cold air flows into the space between the second outer layer 9 and the second middle layer 10 through the cold air pipeline 2 and flows through the grating, the other part of cold air passes through the cold air guide pipe 12 to the hot air inner pipe 8 and flows out from the second inner layer 11, so that the cold air and the hot air pass through the mixing device 5, a guiding effect is achieved on the cold air and the hot.

Claims

1. A coal mill inlet air duct mixing device comprises a hot air pipeline (1) and a cold air pipeline (2), wherein the cold air pipeline (2) is connected with the hot air pipeline (1), a mixing device (5) is arranged at the joint of the cold air pipeline and the hot air pipeline (1), the mixing device (5) is arranged in the hot air pipeline (1), the coal mill inlet air duct mixing device is characterized in that the mixing device (5) comprises a hot air guide pipe and a cold air guide pipe (12), the hot air guide pipe comprises a hot air inner pipe (8), a hot air middle pipe (7) and a hot air outer pipe (6) which are sequentially sleeved, the two ends of the hot air inner pipe (8) are respectively a first inner layer and a second inner layer (11), the two ends of the hot air middle pipe (7) are respectively a first intermediate layer and a second intermediate layer (10), the two ends of the hot air outer pipe (6) are respectively a first outer layer and a second outer layer (9), the first outer, the first inner layer is arranged in a closed mode, a grid is arranged between the second outer layer (9) and the second middle layer (10), the second middle layer (10) and the second inner layer (11) are arranged in a closed mode, and the second inner layer (11) is arranged in an open mode;

the cold air pipeline (2) stretches into the hot air pipeline (1) and extends to the outer wall of the hot air conduit to be vertically connected, wherein one end of the cold air conduit (12) is connected with the cold air pipeline (2), and the other end of the cold air conduit passes through the hot air middle pipe (7) and extends to the outer wall of the hot air inner pipe (8) to be connected.

2. The coal mill inlet duct mixing device of claim 1, characterized in that the number of the grids is plural, and the plural grids are arranged in a ring shape along the second outer layer (9) and the second intermediate layer (10).

3. The coal mill inlet air duct mixing device as claimed in claim 1, characterized in that the size of the mixing device (5) is smaller than the diameter of the hot air duct (1).

4. The coal mill inlet air duct mixing device of claim 1, characterized in that the cold air duct (12) has a smaller diameter than the cold air duct (2).

5. The coal mill inlet air duct mixing device according to claim 1, further comprising an air flow measuring device (3), wherein the air flow measuring device (3) is arranged in the hot air duct (1).

6. The coal mill inlet duct mixing device of claim 1, further comprising a coal mill access port (4), wherein the coal mill access port (4) is connected to an end of the hot air duct (1) remote from the mixing device (5).