CN218645603U

CN218645603U - Pulverized coal fired boiler

Info

Publication number: CN218645603U
Application number: CN202222246311.9U
Authority: CN
Inventors: 马子安; 刘冰; 徐志斌; 田莉勤
Original assignee: Shanghai Bonasen Environmental Technology Co ltd; Shanghai Sifang Boiler Group Engineering System Co ltd
Current assignee: Shanghai Bonasen Environmental Technology Co ltd; Shanghai Sifang Boiler Group Engineering System Co ltd
Priority date: 2022-08-25
Filing date: 2022-08-25
Publication date: 2023-03-17
Anticipated expiration: 2032-08-25

Abstract

The utility model discloses a pulverized coal fired boiler, which comprises a boiler; the boiler comprises a combustion chamber, an over-fire air nozzle is arranged on the combustion chamber and comprises an over-fire air axial pipeline, the over-fire air axial pipeline is arranged on the wall of the combustion chamber, and the air outlet end of the over-fire air axial pipeline penetrates through and extends to the inside of the combustion chamber. The utility model discloses make the overfire air can reach furnace center and furnace inner wall department to nitrogen oxide's content in the reduction flue gas emission.

Description

Pulverized coal fired boiler

Technical Field

The utility model relates to an over fire air field especially relates to a pulverized coal fired boiler.

Background

The overfire air technology is widely used in low-nitrogen combustion of the pulverized coal boiler, a burner on the pulverized coal boiler is mostly arranged in a four-corner tangential circle mode, and the overfire air arrangement mode on the pulverized coal boiler is also generally arranged in a four-corner tangential circle mode. The over-fire air nozzle is arranged at the downstream of the flue gas flow of the combustion chamber, the whole dense and light atmosphere is manufactured in the whole combustion chamber, the air is arranged in a grading way, the fuel is incompletely combusted in the main combustion zone, the reductive intermediate product is generated to reduce the generation of NOx, the reductive reaction is carried out in the reductive zone to reduce the emission of NOx, the incompletely combusted fuel is fully combusted in the over-fire zone, and the complete combustion is ensured. The penetration depth is one of the important parameters of the over-fire air design, and determines whether the over-fire air can completely burn the unburned flue gas.

On present gas boiler, the form of the overfire air spout is comparatively single, and the relative position between the position of arranging the overfire air spout and the water-cooling wall is comparatively single, and the overfire air can not reach furnace center and furnace four walls, causes the high content of CO in the flue gas emission.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a pulverized coal boiler to realize that the over fire air reaches furnace center and furnace inner wall department, thereby nitrogen oxide content in the reduction fume emission.

In order to solve the technical problem, the utility model provides a pulverized coal fired boiler, which comprises a boiler;

the boiler comprises a combustion chamber, an over-fire air nozzle is arranged on the combustion chamber and comprises an over-fire air axial pipeline, the over-fire air axial pipeline is arranged on the wall of the combustion chamber, and the air outlet end of the over-fire air axial pipeline penetrates through the combustion chamber and extends to the inside of the combustion chamber.

Furthermore, the over-fire air axial pipeline is positioned on the side wall inside the combustion chamber and is provided with an over-fire air radial pipeline.

Furthermore, the over-fire air radial pipelines are arranged in a plurality of numbers, and the over-fire air radial pipelines are movably arranged on the outer wall of the over-fire air axial pipeline.

Furthermore, the over-fire air nozzles are arranged in a plurality and are oppositely arranged on the wall of the combustion chamber.

Furthermore, the distance between one end of the over-fire air axial pipeline positioned in the combustion chamber and the inner wall of the combustion chamber is 10-300 mm.

Compared with the prior art, the utility model discloses following beneficial effect has at least: the arrangement that the axial pipeline of the over-fire air goes deep into the combustion chamber adjusts the distance that the axial pipeline of the over-fire air goes deep into the combustion chamber according to the size of the combustion chamber to increase the penetration depth of the over-fire air, and the over-fire air is sprayed out from different directions in the axial direction and the radial direction, so that the over-fire air is mixed in more areas, the incomplete combustion of flue gas is guaranteed, and the thermal efficiency of the boiler is guaranteed.

Drawings

Fig. 1 is a schematic overall structure diagram of an embodiment of the present invention;

fig. 2 is a schematic view of a pulverized coal boiler arrangement with a large depth combustion chamber according to an embodiment of the present invention;

fig. 3 is a schematic view of a pulverized coal boiler arrangement with a small depth combustion chamber according to an embodiment of the present invention;

fig. 4 is a schematic view of the flowing direction of the over-fire air in an embodiment of the present invention.

Detailed Description

The pulverized coal boiler of the present invention will be described in more detail with reference to the drawings, in which preferred embodiments of the present invention are shown, it being understood that those skilled in the art can modify the invention described herein while still achieving the advantageous effects of the present invention. Accordingly, the following description should be construed as broadly as possible to those skilled in the art and not as limiting the invention.

The invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the present invention will become more fully apparent from the following description and appended claims. It should be noted that the drawings are in simplified form and are not to precise scale, and are provided for convenience and clarity in order to facilitate the description of the embodiments of the present invention.

As shown in fig. 1, the embodiment of the present invention provides a pulverized coal fired boiler, which comprises a boiler 1;

boiler 1 includes combustion chamber 11, be provided with after-combustion air spout 2 on the combustion chamber 11, after-combustion air spout 2 is including after-combustion air axial line 21, after-combustion air axial line 21 is installed on the 11 walls of combustion chamber, the end of giving vent to anger of after-combustion air axial line 21 runs through and extends to inside the combustion chamber 11. Set up the end of giving vent to anger of over fire air axial pipeline 21 and run through and extend to combustion chamber 11 inside, increase the penetration depth of over fire air, over fire air can reach furnace center and furnace inner wall department, increase the injection zone and the coal tar dwell time of over fire air, improve the combustion effect in the combustion chamber 11, make over fire air play better over fire and the effect of falling nitrogen, NOx content and CO content in the flue gas that reduces boiler 1 and discharge.

The following is a list of preferred embodiments of the pulverized coal fired boiler for clearly illustrating the contents of the present invention, and it should be understood that the present invention is not limited to the following embodiments, and other modifications by conventional technical means of those skilled in the art are within the scope of the idea of the present invention.

The axial pipe 21 of the overfire air is provided with a radial pipe 22 of the overfire air on the side wall inside the combustion chamber 11, the axial pipe 21 of the overfire air is provided with a radial pipe 22 of the overfire air, the axial pipe 21 of the overfire air is installed on the inner wall of the combustion chamber 11 or the inner wall of the water wall tube, the radial pipe 22 of the overfire air can be arranged in the upper, lower, left and right directions or can be arranged obliquely, please refer to fig. 4, when the radial pipe 22 of the overfire air is vertically upwards arranged on the axial pipe 21 of the overfire air, the flowing direction of the overfire air is indicated, the radial pipe 22 of the overfire air is provided, so that the overfire air and the incompletely combusted smoke are mixed in more areas, especially near the furnace wall of the combustion chamber 11, the combustion effect in the combustion chamber 11 is improved, and the nozzle of the axial pipe 21 of the overfire air is cooled, thereby preventing the nozzle from being damaged due to high temperature, and supplementing air to the edge of the furnace wall, and avoiding dead zones.

The radial over-fire air pipelines 22 are movably mounted on the outer wall of the axial over-fire air pipeline 21, the radial over-fire air pipeline 22 can rotate on the outer wall of the axial over-fire air pipeline 21 to adjust the ejecting direction of over-fire air of the radial over-fire air pipeline 22, the penetration depth of over-fire air is increased, the over-fire air can reach the center of a hearth and the inner wall of the hearth, the ejecting area of the over-fire air and the retention time of coal coke are increased, the over-fire air and incompletely combusted smoke are mixed in more areas, particularly near the wall of the combustion chamber 11, the combustion effect in the combustion chamber 11 is improved, and the NOx content and the CO content in the smoke discharged by the boiler 1 are reduced.

Preferably, the overfire air nozzles 2 are provided with a plurality of nozzles, the overfire air nozzles 2 are arranged on the wall of the combustion chamber 11 relatively, the overfire air nozzles 2 are provided with a plurality of nozzles according to the requirement of the combustion chamber 11, so that the overfire air can be fully filled in the combustion chamber 11, and the combustion effect in the combustion chamber 11 is improved.

Specifically, the over-fire air nozzles 2 can be arranged into a single layer or multiple layers according to the requirements of the combustion chamber 11; wherein, the overfire air nozzles 2 are symmetrically arranged on the inner wall of the combustion chamber 11 or are arranged on the inner wall of the combustion chamber 11 in a crossed manner, so as to ensure that the overfire air sprayed out from the air outlet ends of the axial pipeline 21 and the radial pipeline 22 of the overfire air can be filled in the combustion chamber 11, and thus, a better combustion effect and a nitrogen reduction effect are achieved.

In some specific embodiments, a distance between one end of the over fire air axial conduit 21 located inside the combustion chamber 11 and the inner wall of the combustion chamber 11 is 10mm to 300mm, and a distance D that the over fire air nozzle 2 extends out of the inner wall of the combustion chamber 11 can be adjusted according to the sectional dimension of the combustion chamber 11 and the size of the over fire air nozzle 2, so as to improve the penetration depth of the over fire air.

Specifically, referring to fig. 2, for the combustion chamber 11 with a large cross-sectional size, the distance D that the overfire air nozzle 2 extends out of the inner wall of the combustion chamber 11 increases; referring to fig. 3, for a combustion chamber 11 with a small cross-sectional size, the overfire air nozzle 2 extends a small distance from the inner wall of the combustion chamber 11.

In addition, after-fire air axial conduit 21 can movable mounting on the combustion chamber 11 inner wall for after-fire air axial conduit 21 can carry out the free regulation according to the cross sectional dimension of combustion chamber 11 and the size of after-fire air spout 2, so that combustion chamber 11 reaches better combustion effect, reduces the emission of nitride.

In summary, the arrangement that the axial duct 21 of the overfire air extends into the combustion chamber 11 is adjusted according to the size of the combustion chamber 11, so as to increase the penetration depth of the overfire air, and the overfire air is sprayed out from different directions in the axial direction and the radial direction, so that the overfire air is mixed in more areas, thereby ensuring the full combustion of the incompletely combusted flue gas and ensuring the thermal efficiency of the boiler 1.

It will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A pulverized coal fired boiler is characterized by comprising a boiler;

the boiler comprises a combustion chamber, an over-fire air nozzle is arranged on the combustion chamber and comprises an over-fire air axial pipeline, the over-fire air axial pipeline is arranged on the wall of the combustion chamber, and the air outlet end of the over-fire air axial pipeline penetrates through and extends to the inside of the combustion chamber.

2. Pulverized coal fired boiler according to claim 1 characterized in that the sidewall of the axial conduit for overfire air inside the combustion chamber is provided with radial conduits for overfire air.

3. The pulverized coal fired boiler as defined in claim 2, wherein the over-fired air radial duct is provided in plurality, and the over-fired air radial duct is movably installed on an outer wall of the over-fired air axial duct.

4. Pulverized coal fired boiler according to claim 1, characterized in that a plurality of over-fired air nozzles are provided, which are arranged opposite on the combustion chamber wall.

5. The pulverized coal fired boiler as defined in claim 1, wherein a distance between one end of the axial conduit for overfire air inside the combustion chamber and an inner wall of the combustion chamber is 10mm to 300mm.