A structure and method for reducing smoke temperature deviation in the width direction of the heating surface furnace
By separating the flue in the boiler furnace and setting up an adjustment baffle to adjust the flue gas volume, the problem of large smoke temperature deviation along the furnace width direction is solved, and the uniformity of smoke temperature distribution and wall temperature deviation are achieved is achieved, and the safety and stability of the boiler is improved.
Patent Information
- Application Number
- CN202510070368.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-16
- Publication Date
- 2025-04-04
AI Technical Summary
In the existing supercritical hedging combustion tower primary reheating boiler, the smoke temperature deviation of the heated surface along the furnace width direction is large, resulting in a large wall temperature deviation, which is easy to cause the pipe screen to burst.
By providing front and rear flue partitions and vapor-cooled partition walls in the furnace, the furnace is divided into two front and rear flue channels, and a first and second flue gas adjustment baffles are provided in each flue to adjust the flue gas volume to uniformly distribute the smoke temperature along the width direction of the furnace.
It effectively reduces the smoke temperature deviation of the heating surface along the furnace width direction, reduces the wall temperature deviation, and improves the safe and stable operation of the boiler.
Smart Images
Figure CN119755660A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of boilers, and in particular to a structure and method for reducing smoke temperature deviation in a width direction of a heating surface furnace. Background Art
[0002] The reheat steam temperature of the super (ultra) critical counter combustion tower type single reheat boiler is adjusted by the double flue parallel flue gas regulating damper (the first flue gas regulating damper 1, a parallel flue gas regulating damper for adjusting the reheat steam temperature) arranged at the furnace outlet. If the denitration device is a single reactor, the first flue gas regulating damper 1 is set at one in the front flue and one in the rear flue. If the denitration device is a double reactor, the first flue gas regulating damper 1 is set at two in the front flue and two in the rear flue. For details, see Figure 1 , Figure 2 , the front and rear flue baffles 2 are arranged from the first flue gas regulating baffle 1 of the furnace 10 to the upper part of the economizer 4, from the upper part of the economizer to the lower part of the low-temperature superheater 5 and the low-temperature reheater 6, that is, the upper part of the high-temperature heating surface 7, and the furnace is divided into two front and rear flues at the upper part of the high-temperature heating surface 7 by the steam-cooled partition wall 3. The heat absorption of the low-temperature reheater is adjusted by adjusting the flue gas volume of the two flues, and then the steam temperature at the outlet of the reheater is adjusted. The baffle temperature adjustment force is large and the sensitivity is high. During the execution of the project, due to factors such as the unevenness of the pulverizing system and the deviation of the pulverized coal pipeline, it is inevitable that there will be a flue gas temperature deviation in the width direction of the furnace, which will lead to a large deviation in the wall temperature of the tube screen along the width direction of the furnace. Long-term wall temperature overheating will damage the heating surface due to stress fatigue, and it is easy to burst the tube, so it is very important to reduce the flue gas temperature deviation on both sides of the heating surface furnace.
[0003] In summary, the current flue gas temperature deviation on both sides of the furnace outlet of the supercritical (ultra) thermal power unit counter-combustion boiler is generally within 50°C, but the flue gas temperature deviation along the width of the furnace is higher, which can reach 100°C or even higher. Large flue gas temperature deviation leads to large wall temperature deviation. Long-term operation of the boiler causes stress fatigue damage to the heating surface, and the tube screen is prone to bursting. More and more users are aware of the importance of wall temperature deviation control. Some projects require that the furnace outlet flue gas temperature deviation be controlled within 25°C, which puts great design pressure on boiler plants. Summary of the invention
[0004] In order to overcome the deficiencies of the prior art, the present invention provides a structure and method for reducing the smoke temperature deviation of the heating surface in the furnace width direction, thereby solving the problem of large wall temperature deviation of the tube panel along the furnace width direction existing in the prior art.
[0005] The technical solution adopted by the present invention to solve the above problems is:
[0006] A structure for reducing the smoke temperature deviation of a heating surface in a furnace width direction, comprising a furnace, a first smoke regulating baffle arranged at a furnace outlet, and also comprising front and rear flue baffles, a steam-cooled partition wall, an economizer, a low-temperature superheater, a low-temperature reheater, and a high-temperature heating surface arranged in the furnace, the first smoke regulating baffle, the front and rear flue baffles, the economizer, the low-temperature superheater, and the high-temperature heating surface being arranged from top to bottom, the first smoke regulating baffle, the front and rear flue baffles, the economizer, the low-temperature superheater, the low-temperature reheater, and the high-temperature heating surface being arranged from top to bottom, the first smoke regulating baffle is connected to the front and rear flue baffles, the steam-cooled partition wall extends from above the economizer to the space below the low-temperature superheater and above the high-temperature heating surface, the steam-cooled partition wall extends from above the economizer to the space below the low-temperature reheater and above the high-temperature heating surface, and the steam-cooled partition wall divides the flue into a front flue and a rear flue.
[0007] As a preferred technical solution, it includes a second flue gas regulating baffle arranged at the junction of the front and rear flue baffles and the steam cooling partition wall.
[0008] As a preferred technical solution, it includes a heating surface partition, which divides the flue located in the steam-cooled partition area into N areas along the width direction of the furnace, and the second flue gas regulating baffle is arranged in the front flue and the rear flue of each area; wherein N≥2 and N is an integer.
[0009] As a preferred technical solution, the heated surface partition has an anti-vibration function.
[0010] As a preferred technical solution, the second smoke regulating baffle is provided with an electric actuator or a pneumatic actuator.
[0011] As a preferred technical solution, a denitrification device is provided downstream of the flue gas of the first flue gas regulating baffle. If the denitrification device is a single reactor, the first flue gas regulating baffle is provided in each of the front flue and the rear flue.
[0012] As a preferred technical solution, a denitrification device is provided downstream of the flue gas of the first flue gas regulating baffle. If the denitrification device is a double reactor, two first flue gas regulating baffles are provided in the front flue and two in the rear flue respectively.
[0013] A method for reducing the smoke temperature deviation of a heating surface in the width direction of a furnace, using the structure for reducing the smoke temperature deviation of a heating surface in the width direction of a furnace to adjust the smoke volume of a front flue and / or a rear flue, thereby reducing the smoke temperature deviation of the heating surface along the width direction of the furnace.
[0014] As a preferred technical solution, a structure for reducing the smoke temperature deviation of the heating surface in the furnace width direction includes a second smoke regulating damper arranged at the junction of the front and rear flue baffles and the steam-cooled partition wall. When in use, after adjusting the opening of the first smoke regulating damper under a certain working condition, based on the correspondence between the second smoke regulating damper and the tube screen and by analyzing the distribution of the heating surface wall temperature measuring points in the furnace width direction, the heating surface wall temperature deviation ΔT value is calculated, a logical relationship is established between the ΔT value and the opening of the second smoke regulating damper, the maximum and minimum points of the ΔT value are found, and the opening of the second smoke regulating damper corresponding to the maximum point and / or the minimum point is adjusted, thereby reducing the smoke temperature deviation of the heating surface in the furnace width direction; wherein, the tube screen is an economizer, a low-temperature superheater or a low-temperature reheater, and the ΔT value = the average wall temperature Tx of a single tube screen - the average wall temperature Tp of all tube screens of the heating surface.
[0015] As a preferred technical solution, the method for adjusting the opening of the second smoke regulating damper corresponding to the maximum point and / or the minimum point is: reducing the opening of the second smoke regulating damper corresponding to the maximum point of the ΔT value, and / or increasing the opening of the second smoke regulating damper corresponding to the minimum point of the ΔT value.
[0016] As a preferred technical solution,
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] The present invention adjusts the flue gas volume to evenly distribute the flue gas temperature on the heating surface along the width direction of the furnace, thereby reducing the temperature deviation of the heating surface along the walls on both sides of the furnace, thereby ensuring safe and stable operation of the boiler. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is the layout diagram of the heating surface and smoke regulating damper of the prior art;
[0020] Figure 2 for Figure 1 A side view of the A direction;
[0021] Figure 3 It is the layout diagram of the heating surface and the smoke regulating baffle of the present invention;
[0022] Figure 4 for Figure 3 Side view in direction A.
[0023] Marks and their corresponding names in the attached drawings: 1-first flue gas regulating damper, 2-front and rear flue partitions, 3-steam cooling partition wall, 4-economizer, 5-low-temperature superheater, 6-low-temperature reheater, 7-high-temperature stage heating surface, 8-heating surface partition, 9-second flue gas regulating damper, 10-furnace. DETAILED DESCRIPTION
[0024] The present invention will be further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.
[0025] Example 1
[0026] like Figure 3 to Figure 4 As shown, taking the hedge tower furnace (type is not limited to this) as an example, the present invention proposes a new structure and adjustment system, which adjusts the flue gas volume to evenly distribute the flue gas temperature on the heating surface along the width direction of the furnace, thereby reducing the temperature deviation of the heating surface along the walls on both sides of the furnace, thereby ensuring safe and stable operation of the boiler.
[0027] The boiler is arranged in a tower style, using front and rear wall counter-combustion.
[0028] The flue gas flows from bottom to top, and the main heating surfaces from bottom to top are: high-temperature heating surface 7, low-temperature superheater 5 and low-temperature reheater 6 arranged with front and rear double flues, and economizer 4. Among them, in this embodiment, the low-temperature superheater 5 uses a superheater with a flue gas temperature range of 400-900°C, the low-temperature reheater 6 uses a reheater with a flue gas temperature range of 400-900°C, and the high-temperature heating surface 7 uses a heating surface with a flue gas temperature range of about 900°C or above. It is worth noting that the "low temperature" and "high temperature" in the low-temperature superheater, low-temperature reheater, and high-temperature heating surface of the present invention are not limited to the above ranges, or even to specific ranges. Such names mainly express that the flue gas temperature of the high-temperature heating surface is higher than the flue gas temperature of the low-temperature superheater and the low-temperature reheater.
[0029] Preferably, the steam temperature of the low-temperature reheater 6 is adjusted by a first flue gas adjustment damper 1 arranged at the outlet of the furnace 10 .
[0030] A denitration device is provided downstream of the flue gas of the first flue gas regulating baffle 1. If the denitration device is a single reactor, one first flue gas regulating baffle 1 is provided at the front flue and one at the rear flue; if the denitration device is a double reactor, two first flue gas regulating baffles 1 are provided at the front flue and two at the rear flue. Figure 3 , Figure 4 .
[0031] Preferably, the front and rear flue baffles 2 are arranged from the first flue gas regulating baffle 1 at the furnace outlet to the upper part of the economizer 4; from the upper part of the economizer to the lower part of the low-temperature superheater 5 and the low-temperature reheater 6, that is, the upper part of the high-temperature heating surface 7, the furnace is divided into two front and rear flues at the upper part of the high-temperature heating surface 7 through the steam-cooled partition wall 3. The heat absorption of the low-temperature reheater is adjusted by adjusting the flue gas volume of the two flues, thereby adjusting the steam temperature at the reheater outlet.
[0032] Preferably, the front and rear flues on the economizer are divided into four uniform areas along the width direction of the furnace and separated by the heating surface partition 8. In each separated area, parallel flue gas regulating baffles (second flue gas regulating baffles 9, which are used to adjust the flue gas temperature deviation of the heating surface along the two sides of the furnace) are arranged at the junction of the front and rear flue partitions 2 and the steam cooling partition wall 3. Four baffles are arranged in each front and rear flue. See Figure 2 By adjusting the opening of the second flue gas regulating damper 9, the flue gas temperature deviation of the low-temperature reheater 6 and the low-temperature superheater 5 along both sides of the furnace is adjusted, thereby adjusting the steam temperature deviation.
[0033] Preferably, after adjusting the opening of the first flue gas regulating damper 1 under a certain working condition, based on the correspondence between the second flue gas regulating damper 9 and the tube screen (economizer 4, low-temperature superheater 5, low-temperature reheater 6) (each second flue gas regulating damper 9 covers a specific tube screen in the corresponding vertical area) and by analyzing the distribution of the heating surface wall temperature measurement points in the furnace width direction, the heating surface wall temperature deviation ΔT value (the average wall temperature Tx of a single tube screen-the average wall temperature Tp of all tube screens on the heating surface, which can be positive or negative) is calculated, and a logical relationship is established between the ΔT value and the opening of the second flue gas regulating damper 9, and the maximum and minimum points of the ΔT value are found. The opening of the second flue gas regulating damper 9 corresponding to the maximum and minimum points of the tube screen is adjusted, the opening of the second flue gas regulating damper 9 corresponding to the maximum point of the ΔT value is reduced, and the opening of the second flue gas regulating damper 9 corresponding to the minimum point of the ΔT value is increased, and the overall temperature distribution is adjusted to develop in the direction of smaller deviation.
[0034] In the present invention, in order to reduce the wall temperature deviation on both sides of the furnace of the heating surface of the hedging tower furnace, the heating surface is divided into four areas along the width direction of the furnace, each area corresponds to a specific tube screen, and a flue gas regulating baffle is set in each area. The flue gas volume is adjusted by partitioning, so as to evenly distribute the flue gas temperature of the heating surface along the width direction of the furnace, thereby reducing the wall temperature deviation of the heating surface along the width direction of the furnace, and adjusting the overall temperature distribution to develop in the direction of smaller deviation.
[0035] Preferably, the heating surface partition 8 can be used as an anti-vibration partition (also having an anti-vibration function); the second smoke regulating baffle 9 can be automatically adjusted, that is, the second smoke regulating baffle 9 is equipped with an electric or pneumatic actuator to achieve fully automatic quick adjustment.
[0036] As described above, the present invention can be preferably implemented.
[0037] All features disclosed in all embodiments in this specification, or steps in all methods or processes implicitly disclosed, except for mutually exclusive features and / or steps, can be combined and / or expanded or replaced in any manner.
[0038] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. According to the technical essence of the present invention, within the spirit and principles of the present invention, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the present invention.
Claims
1. A structure for reducing the smoke temperature deviation in the width direction of the heating surface furnace, characterized in that: The invention comprises a furnace (10), a first flue gas regulating baffle (1) arranged at the outlet of the furnace (10), and also comprises front and rear flue baffles (2) arranged in the furnace (10), a steam cooling partition wall (3), an economizer (4), a low-temperature superheater (5), a low-temperature reheater (6), and a high-temperature heating surface (7). The first flue gas regulating baffle (1), the front and rear flue baffles (2), the economizer (4), the low-temperature superheater (5), and the high-temperature heating surface (7) are arranged from top to bottom. 4), a low-temperature superheater (5), a low-temperature reheater (6), and a high-temperature heating surface (7) are arranged from top to bottom, the first flue gas regulating damper (1) is connected to the front and rear flue partitions (2), the steam-cooled partition wall (3) extends from the top of the economizer (4) to the space below the low-temperature superheater (5) and above the high-temperature heating surface (7), the steam-cooled partition wall (3) extends from the top of the economizer (4) to the space below the low-temperature reheater (6) and above the high-temperature heating surface (7), and the steam-cooled partition wall (3) divides the flue into a front flue and a rear flue.
2. The structure for reducing the smoke temperature deviation in the width direction of the heating surface furnace according to claim 1 is characterized in that: It comprises a second smoke regulating baffle (9) arranged at the junction of the front and rear smoke duct baffles (2) and the steam cooling partition wall (3).
3. The structure for reducing smoke temperature deviation in the width direction of the heating surface furnace according to claim 2 is characterized in that: It comprises a heating surface partition (8), which divides the flue located in the steam cooling partition wall (3) area into N areas along the width direction of the furnace (10), and a second flue gas regulating damper (9) is arranged in the front flue and the rear flue of each area; wherein N≥2 and N is an integer.
4. The structure for reducing smoke temperature deviation in the width direction of the heating surface furnace according to claim 3 is characterized in that: The heating surface partition (8) has an anti-vibration function.
5. The structure for reducing smoke temperature deviation in the width direction of the heating surface furnace according to claim 2 is characterized in that: The second smoke regulating damper (9) is provided with an electric actuator or a pneumatic actuator.
6. A structure for reducing smoke temperature deviation in the width direction of the heating surface furnace according to any one of claims 1 to 5, characterized in that: A denitration device is provided downstream of the flue gas of the first flue gas regulating baffle (1). If the denitration device is a single reactor, one first flue gas regulating baffle (1) is provided in the front flue and one in the rear flue.
7. A structure for reducing smoke temperature deviation in the width direction of the heating surface furnace according to any one of claims 1 to 5, characterized in that: A denitration device is provided downstream of the flue gas of the first flue gas regulating baffle (1). If the denitration device is a double reactor, two first flue gas regulating baffles (1) are provided in the front flue and two in the rear flue, respectively.
8. A method for reducing the smoke temperature deviation in the width direction of the heating surface furnace, characterized in that: The structure for reducing the smoke temperature deviation of the heating surface in the width direction of the furnace as described in any one of claims 1 to 7 is used to adjust the smoke volume of the front flue and / or the rear flue, thereby reducing the smoke temperature deviation of the heating surface along the width direction of the furnace (10).
9. A method for reducing smoke temperature deviation in the width direction of the heating surface furnace according to claim 8, characterized in that: A structure for reducing the smoke temperature deviation in the width direction of a heating surface furnace comprises a second smoke regulating damper (9) arranged at the junction of a front and rear smoke duct partition (2) and a steam cooling partition wall (3). When in use, after adjusting the opening of the first smoke regulating damper (1) under a certain working condition, based on the corresponding relationship between the second smoke regulating damper (9) and the tube screen and by analyzing the distribution of the heating surface wall temperature measurement points in the width direction of the furnace (10), the heating surface wall temperature deviation ΔT value is calculated, a logical relationship is established between the ΔT value and the opening of the second smoke regulating damper (9), the maximum point and the minimum point of the ΔT value are found, and the opening of the second smoke regulating damper (9) corresponding to the maximum point and / or the minimum point is adjusted, thereby reducing the smoke temperature deviation in the width direction of the heating surface furnace (10); wherein the tube screen is an economizer (4), a low-temperature superheater (5) or a low-temperature reheater (6), and the ΔT value = the average wall temperature Tx of a single tube screen - the average wall temperature Tp of all tube screens of the heating surface.
10. A method for reducing smoke temperature deviation in the width direction of the heating surface furnace according to claim 9, characterized in that: The method for adjusting the opening of the second smoke regulating damper (9) corresponding to the maximum point and / or the minimum point is: reducing the opening of the second smoke regulating damper (9) corresponding to the maximum point of the ΔT value, and / or increasing the opening of the second smoke regulating damper (9) corresponding to the minimum point of the ΔT value.