Horizontal flue structure adaptive to coal with strong coking property
By designing water-cooled wall structures with different inclinations in the boiler horizontal flue, the problem of difficult to clean up coking and ash in the boiler flue under strong coking coal quality is solved, and the effective discharge and maintenance of coking blocks and ash is achieved, ensuring that The safe and economical operation of the boiler.
Patent Information
- Application Number
- CN202323331505.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-07
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2033-12-07
AI Technical Summary
When the existing boiler horizontal flue structure uses strong coking coal, it is prone to coking and contamination, and it is difficult to effectively clean up the coking blocks and ash at the bottom of the horizontal flue, affecting the safety and economical operation of the boiler.
A horizontal flue structure consisting of water-cooled walls at the front and rear sections with different horizontal inclinations is designed. The inclination angle of the water-cooled wall at the front section is greater than that of the water-cooled wall at the back section. The inflection point is located below the outlet position of the front tube bundle of the high-temperature reheater, which is convenient to use gravity. The coke blocks and dust accumulation are discharged, and the maintenance space is increased.
The coke blocks and ash accumulated at the bottom of the horizontal flue are effectively and conveniently discharged, simplifying the maintenance process and ensuring the safe, economical and reliable operation of the boiler.
Smart Images
Figure CN222256636U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a horizontal flue structure of a boiler, in particular to a horizontal flue structure suitable for coal with strong coking property. Background Art
[0002] The conventional supercritical boiler horizontal flue structure is shown in the attached figure. Figure 1 As shown, the bottom water-cooled wall 11 in the horizontal flue 19 extends out at a certain inclination angle after passing through the slag condensing pipe 13 from the furnace flame deflection angle 12. The turning angle is reduced to about 5° at the turning point 15 of the water-cooled wall 11 at the bottom of the horizontal flue and extends to the position of the front wall 16 of the rear shaft flue; the turning point 15 of the water-cooled wall 11 at the bottom of this horizontal flue is relatively close to the slag condensing pipe 13 on the rear wall of the furnace, generally not exceeding 500mm; the high-temperature superheater 17 of the boiler is arranged above the furnace flame deflection angle 12, and its bottom inclination angle is the same as that of the flame deflection angle 12; the high-temperature reheater 18 of the boiler is arranged in the horizontal flue 19, and the bottom is arranged horizontally.
[0003] This structure works well when burning conventional coal and has been applied to a large number of supercritical (ultra) boilers; however, when the boiler burns strong coking coal such as Zhundong high-alkali coal, the following problems often occur: Since the horizontal flue 19 is located after the furnace outlet, the flue gas temperature here is 800~1200℃ during normal operation. When burning strong coking and strong contamination coal such as Zhundong high-alkali coal, the horizontal flue heating surface is prone to coking and contamination, and a soot blower needs to be used to remove the coke on the heating surface. Since the horizontal inclination angle of the water-cooled wall 11 at the bottom of the horizontal flue is small, the coke blocks blown down by the soot blower and the ash accumulated during boiler operation accumulate here and are difficult to discharge; at the same time, since the space between the bottom of the high-temperature reheater 18 and the water-cooled wall 11 at the bottom of the horizontal flue is small, it is not conducive to cleaning the coke and ash during maintenance.
[0004] For the ash accumulation at the bottom of the horizontal flue, a soot blowing device is often installed at the ash accumulation part at the bottom of the horizontal flue. When the soot blowing device is running, the deposited fly ash is lifted up and carried into the economizer ash hopper and the dust collector at the boiler outlet with the flue gas, and then discharged through the ash conveying device. However, in actual use, there are problems such as limited cleaning range, difficulty in clearing dead corners, and large consumption of working fluid. Especially for coal with strong coking properties, the coking on the heating surface of the horizontal flue falls to the bottom of the horizontal flue after soot blowing, and it is even more difficult to discharge it by blowing. Therefore, the simple blowing and cleaning method has limited effect on furnaces with serious ash accumulation. Summary of the invention
[0005] The purpose of the utility model is to address the above-mentioned deficiencies in the prior art and to provide a horizontal flue structure that is suitable for highly coking coal, which can conveniently discharge coke blocks and ash accumulation at the bottom of the horizontal flue, and is also convenient for cleaning coke blocks and ash accumulation in the horizontal flue during maintenance, thereby ensuring safe, economical and reliable operation of the boiler.
[0006] In order to achieve the above-mentioned purpose, the utility model provides a horizontal flue structure suitable for strong coking coal, including a horizontal flue, a high-temperature reheater arranged in the horizontal flue and a water-cooled wall at the bottom of the horizontal flue; the characteristic is that the water-cooled wall at the bottom of the horizontal flue includes a front bottom water-cooled wall and a rear bottom water-cooled wall with different horizontal inclination angles, the horizontal inclination angle of the front bottom water-cooled wall is greater than the horizontal inclination angle of the rear bottom water-cooled wall, and the inflection point of the front bottom water-cooled wall and the rear bottom water-cooled wall is located below the front tube bundle outlet position of the high-temperature reheater.
[0007] The utility model sets the inflection point of the front section bottom water-cooled wall and the rear section bottom water-cooled wall below the outlet position of the front tube bundle of the high-temperature reheater. During the operation of the boiler, coking in the horizontal flue usually occurs on the windward side of the high-temperature reheater, that is, at the front tube bundle. When blowing soot, the horizontal inclination angle of the front section bottom water-cooled wall below the coke is large, and gravity can be used to conveniently discharge coke blocks and accumulated ash. At the same time, the large horizontal inclination angle increases the inspection space of the high-temperature reheater and the bottom water-cooled wall of the horizontal flue, which is convenient for inspecting and cleaning the coke and accumulated ash of the horizontal flue. The horizontal inclination angle of the rear section bottom water-cooled wall is small, which has little effect on the arrangement of the heating surface of the high-temperature reheater, and can still ensure the arrangement of sufficient heating surfaces, ensure that the boiler reaches the rated steam temperature, and ensure the safe, economical and reliable operation of the boiler.
[0008] As a further improvement of the utility model, the horizontal inclination angle of the water-cooled wall at the bottom of the front section is not less than 30°, and the horizontal inclination angle of the water-cooled wall at the bottom of the rear section is 1°-5°; the horizontal inclination angle of the water-cooled wall at the bottom of the front section is not less than 30°, which can better utilize gravity to discharge coke and ash accumulation;
[0009] As a further improvement of the utility model, the horizontal inclination angle of the water-cooled wall at the bottom of the front section is the same as the horizontal inclination angle of the water-cooled wall at the rear wall at the flame bending angle of the furnace, so that the coke and ash can slide into the furnace and reignite.
[0010] In summary, the utility model can conveniently discharge coke blocks and ash accumulation at the bottom of the horizontal flue, and is also convenient for cleaning coke blocks and ash accumulation in the horizontal flue during maintenance, thereby ensuring safe, economical and reliable operation of the boiler. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 This is a schematic diagram of the existing horizontal flue structure.
[0012] Figure 2 It is a schematic diagram of an embodiment of the utility model. DETAILED DESCRIPTION
[0013] The utility model is further described below in conjunction with the accompanying drawings.
[0014] like Figure 2As shown, a horizontal flue structure suitable for strong coking coal of this embodiment includes a horizontal flue 1, a high-temperature reheater 2 arranged in the horizontal flue 1 and a horizontal flue bottom water-cooled wall 3; the horizontal flue bottom water-cooled wall 3 includes a front section bottom water-cooled wall 3-1 and a rear section bottom water-cooled wall 3-2 with different horizontal inclination angles, the horizontal inclination angle of the front section bottom water-cooled wall 3-1 is not less than 30° and is the same as the horizontal inclination angle of the rear wall water-cooled wall 4 at the furnace flame deflection angle 6, the horizontal inclination angle of the rear section bottom water-cooled wall 3-2 is 5°, and the inflection point 5 between the front section bottom water-cooled wall 3-1 and the rear section bottom water-cooled wall 3-2 is located below the outlet position of the front tube bundle 2-1 of the high-temperature reheater 2.
[0015] The utility model sets the inflection point 5 of the front section bottom water-cooled wall 3-1 and the rear section bottom water-cooled wall 3-2 below the outlet position of the front tube bundle 2-1 of the high-temperature reheater 2. During the operation of the boiler, coking in the horizontal flue usually occurs on the windward side of the high-temperature reheater 2, that is, the front tube bundle 2-1. When soot blowing, the horizontal inclination angle of the front section bottom water-cooled wall 3-1 below the coke is relatively large, and the coke and ash can be conveniently discharged by gravity, and slide into the furnace and re-ignited; at the same time, the large horizontal inclination angle increases the maintenance space of the high-temperature reheater 2 and the bottom water-cooled wall of the horizontal flue, which is convenient for maintenance and cleaning of the coke and ash in the horizontal flue. The horizontal inclination angle of the rear section bottom water-cooled wall 3-2 is relatively small, which has little effect on the arrangement of the heating surface of the high-temperature reheater 2, and can still ensure the arrangement of sufficient heating surface, ensure that the boiler reaches the rated steam temperature, and ensure the safe, economical and reliable operation of the boiler;
[0016] The above embodiments are used for illustration, but it should be understood that the above embodiments are only used for the purpose of example and description, and are not intended to limit the present invention to the scope of the described embodiments.
Claims
1. A horizontal flue structure adapted to strong coking coal, comprising a horizontal flue, a high-temperature reheater disposed in the horizontal flue, and a water-cooled wall at the bottom of the horizontal flue; characterized in that: The horizontal flue bottom water-cooled wall includes a front section bottom water-cooled wall and a rear section bottom water-cooled wall with different horizontal inclination angles. The horizontal inclination angle of the front section bottom water-cooled wall is greater than that of the rear section bottom water-cooled wall. The inflection point of the front section bottom water-cooled wall and the rear section bottom water-cooled wall is located below the front tube bundle outlet of the high-temperature reheater.
2. A horizontal flue structure adapted to strong coking coal as claimed in claim 1, characterized in that: The horizontal inclination angle of the water-cooled wall at the bottom of the front section is not less than 30°, and the horizontal inclination angle of the water-cooled wall at the bottom of the rear section is 1°-5°.
3. A horizontal flue structure adapted to strong coking coal as claimed in claim 1 or 2, characterized in that: The horizontal inclination angle of the water-cooled wall at the bottom of the front section is the same as the horizontal inclination angle of the water-cooled wall at the rear wall at the flame deflection angle of the furnace.