Method for improving high-temperature corrosion of burner nozzle area of opposed firing boiler

Abstract

The invention discloses a method for improving high-temperature corrosion of a burner nozzle area of an opposed firing boiler, which relates to the technical field of boiler prevention and control and comprises the following steps: acquiring relevant data of the boiler, judging the state, and checking a burner if the boiler is in a cold-state shutdown period of the boiler; based on the inspection of the combustor, inspecting the shape of a nozzle of the combustor and internal and external secondary air doors of the combustor, and performing grid test and inspection on the primary air speed of the nozzle of the combustor and the internal and external secondary air speeds of the nozzle of the combustor to obtain an inspection result of the combustor; and a high-temperature corrosion prevention and control strategy is made based on the inspection result of the combustor, and positioning and treatment of high-temperature corrosion of the nozzle area of the combustor of the opposed firing boiler are achieved. According to the method, the reason for high-temperature corrosion of the burner nozzle area is located from the source, targeted adjustment and treatment are carried out, the high-temperature corrosion problem existing in the burner nozzle area is effectively solved, the pertinence is high, and the effect is remarkable.

Description

Technical Field

[0001] The invention relates to the technical field of boiler prevention and treatment, in particular to a method for improving high temperature corrosion in a nozzle area of ​​a burner of a counter-firing boiler. Background Art

[0002] With increasingly stringent environmental protection requirements, domestic coal-fired boilers now generally adopt low-nitrogen combustion technology to reduce nitrogen oxide emissions. However, the widespread application of low-nitrogen combustion technology has also brought a series of new challenges; in recent years, with the long-term operation of low-nitrogen combustion boilers and the blending of high-sulfur coal under high coal prices, the problem of high-temperature corrosion of boiler water-cooled walls has become one of the main problems affecting the safe operation of power plants, especially for hedge-fired boilers. Due to the unique structural characteristics of hedge-fired boilers, the problem of high-temperature corrosion is more prominent; traditionally, the area where high-temperature corrosion of the water-cooled walls occurs in hedge-fired boilers is mainly located between the side wall burner and the burnout air, and the corresponding countermeasures are becoming more and more perfect and mature. However, recent observations have found that high-temperature corrosion has also begun to occur in the burner nozzle area, and this phenomenon has attracted great attention from the industry. At present, power plants generally use water-cooled wall anti-corrosion spraying to deal with the high-temperature corrosion problem in the burner nozzle area. Although this method can alleviate high-temperature corrosion to a certain extent, it has several obvious defects. First, water-cooled wall anti-corrosion spraying is a passive protection method and cannot fundamentally solve the problem. Secondly, the spraying effect lasts for a short time and requires frequent repeated spraying, which increases maintenance costs and downtime. Finally, the water-cooled wall anti-corrosion spraying method cannot diagnose and treat the root cause of corrosion, resulting in repeated problems.

[0003] The common solutions currently available have many shortcomings, including: for the prevention and control of high-temperature corrosion in the burner nozzle area, existing monitoring and prevention measures are often limited to the observation of a single parameter, such as focusing only on combustion temperature or flue gas composition, and lacking an overall grasp of the combustion process; at the same time, traditional inspection methods mostly rely on regular shutdowns for maintenance, which makes it difficult to detect and deal with problems in a timely manner. In terms of burner adjustment, existing technologies often use empirical adjustment methods and lack scientific and systematic optimization strategies; in addition, existing technologies generally lack accurate measurement and analysis of airflow distribution in the burner nozzle area, which makes it difficult to accurately locate and solve the root cause of the high-temperature corrosion problem, and cannot fundamentally solve the high-temperature corrosion problem in the burner nozzle area. Summary of the invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is how to provide a method for improving high temperature corrosion in the burner nozzle area of ​​a hedge combustion boiler, and fundamentally solve the problem of high temperature corrosion in the burner nozzle area.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In the first aspect, an embodiment of the present invention provides a method for improving high-temperature corrosion in the nozzle area of ​​a burner of a hedge combustion boiler, which includes obtaining relevant data of the boiler and making a status judgment. If the boiler is in a cold shutdown period, the burner is inspected; based on the inspection of the burner, the nozzle shape of the burner and the internal and external secondary air dampers of the burner are inspected, and the primary wind speed of the burner nozzle and the internal and external secondary wind speeds of the burner nozzle are grid tested and inspected to obtain the inspection result of the burner; based on the inspection result of the burner, a high-temperature corrosion prevention and control strategy is formulated to achieve the positioning and control of high-temperature corrosion in the nozzle area of ​​the hedge combustion boiler.

[0008] As a preferred scheme of the method for improving high-temperature corrosion in the nozzle area of ​​a counter-firing boiler burner according to the present invention, the relevant data of the boiler include the operating status of the boiler, the nozzle shape of the burner, the opening of the inner and outer secondary air dampers of the burner, the wind speed of the primary air nozzle of the burner, and the wind speed of the inner and outer secondary air nozzles of the burner; the status judgment refers to judging the operating status of the boiler, analyzing whether the boiler is in a cold shutdown period or a hot operation period.

[0009] As a preferred solution of the method for improving high-temperature corrosion in the nozzle area of ​​a counter-firing boiler burner described in the present invention, the formulation of a high-temperature corrosion prevention and control strategy includes the following steps: when the boiler is in a cold shutdown period, the shape of the burner nozzle is checked. If the burner has cone expansion burnout, combustion stabilizing tooth burnout, burner nozzle primary air duct blockage, burner nozzle secondary air duct blockage or burner nozzle coking, the power plant maintenance personnel are notified to eliminate the fault; otherwise, the burner nozzle shape is determined to be normal, and the next step is executed; during the cold shutdown period of the boiler, the flexibility of the internal and external secondary air valves of the burner is checked to ensure that the internal and external secondary air valves of the burner are flexible and adjustable; the opening of the internal and external secondary air valves of the burner is adjusted. Carry out an inspection by checking the original openings of the inner and outer secondary air dampers of the burner, and enter the wind box to verify the actual openings of the inner and outer secondary air dampers. If the original openings of the inner and outer secondary air dampers ≠ the actual openings of the inner and outer secondary air dampers, notify the power plant maintenance personnel to inspect the inner and outer secondary air dampers; if the original openings of the inner and outer secondary air dampers = the actual openings of the inner and outer secondary air dampers, it is determined that the accuracy of the inner and outer secondary air dampers of the burner is good, and execute the next step; under cold ventilation conditions, perform a grid method wind speed test on the upper, lower, left and right positions of the primary air nozzle of the burner. If there is a local area with a wind speed ≤ the first threshold in the upper, lower, left or right positions of the primary air nozzle of the burner, check whether there is foreign matter in the primary channel upstream of the burner nozzle. If there is foreign matter, then Notify the power plant maintenance personnel to eliminate the fault; if there is no foreign matter, it is determined that there is an abnormality in the boiler, and notify the power plant maintenance personnel to repair the boiler; if the wind speed in all areas of the upper, lower, left or right position of the primary air nozzle of the burner is greater than the first threshold, it is determined that the primary channel upstream of the burner nozzle is normal, and execute the next step; under cold ventilation conditions, the upper, lower, left and right positions of the secondary air nozzles inside and outside the burner are tested for wind speed using the grid method. If there is a local area in the upper, lower, left or right position of the secondary air nozzle in the burner with a wind speed ≤ the second threshold, check whether there is foreign matter in the secondary channel upstream of the secondary air nozzle in the burner. If there is foreign matter, notify the power plant maintenance personnel to eliminate the fault; if there is no foreign matter, it is determined that there is an abnormality in the boiler, and notify the power plant maintenance personnel to eliminate the fault; The power plant maintenance personnel are informed to perform maintenance on the boiler; if the wind speed of all areas in the upper, lower, left or right position of the secondary air nozzle in the burner is greater than the second threshold, the secondary passage upstream of the secondary air nozzle in the burner is determined to be normal; if the wind speed of a local area in the upper, lower, left or right position of the secondary air nozzle outside the burner is ≤ the third threshold, check whether there is foreign matter in the secondary passage upstream of the secondary air nozzle outside the burner, and if there is foreign matter, notify the power plant maintenance personnel to eliminate the fault; if there is no foreign matter, it is determined that the boiler is abnormal, and the power plant maintenance personnel are notified to perform maintenance on the boiler; if the wind speed of all areas in the upper, lower, left or right position of the secondary air nozzle outside the burner is greater than the third threshold, it is determined that the secondary passage upstream of the secondary air nozzle outside the burner is normal, and the next step is executed;After the fault elimination process, the boiler is subjected to a cold fireworks tracer test to simulate and evaluate the combustion state of the burner nozzle; after the burner inspection is completed during the cold shutdown period of the boiler, when the boiler is in hot operation, the internal and external secondary air dampers of the burner are adjusted based on the inspection results of the burner during the cold shutdown period of the boiler to determine the internal and external secondary air volume and entrainment intensity. ;

[0010] As a preferred scheme of the method for improving high-temperature corrosion in the nozzle area of ​​a counter-firing boiler burner described in the present invention, the inspection of the nozzle shape of the burner includes inspecting the burning condition of the burner expansion cone, the burning condition of the stabilizing teeth, the blockage condition of the primary air duct of the burner nozzle, the blockage condition of the secondary air duct of the burner nozzle and the coking condition of the burner nozzle.

[0011] As a preferred solution of the method for improving high-temperature corrosion in the nozzle area of ​​a counter-firing boiler burner described in the present invention, the inspection of the internal and external secondary air dampers of the burner includes: during cold shutdown of the boiler, inspecting the original openings of the internal and external secondary air dampers of the burner; entering the inside of the bellows to verify the actual openings of the internal and external secondary air dampers; ensuring that the internal and external secondary air dampers are flexibly adjustable; and during hot operation of the boiler, adjusting and optimizing the internal and external secondary air volume and swirl intensity of the burner.

[0012] As a preferred scheme of the method for improving high-temperature corrosion in the burner nozzle area of ​​a counter-firing boiler described in the present invention, grid testing and inspection of the primary wind speed of the burner nozzle refers to performing grid wind speed tests on the upper, lower, left and right positions of the primary air nozzle of the burner under cold ventilation conditions; grid testing and inspection of the internal and external secondary wind speeds of the burner nozzle refers to performing grid wind speed tests on the upper, lower, left and right positions of the secondary air nozzle inside the burner and the secondary air nozzle outside the burner under cold ventilation conditions.

[0013] As a preferred solution of the method for improving high-temperature corrosion in the nozzle area of ​​a counter-firing boiler burner described in the present invention, the adjustment of the internal and external secondary air dampers of the burner refers to increasing the internal and external secondary air volume of the burner during hot operation of the boiler, combined with the powder distribution of the powder pipe, while ensuring uniform combustion along the width of the furnace.

[0014] Secondly, in order to further solve the safety problems existing in boiler prevention and control, the present invention provides a system for improving high-temperature corrosion in the nozzle area of ​​a counter-combustion boiler burner in an embodiment, which includes: an operating status module, which is used to obtain the operating status of the boiler, the nozzle shape of the burner, the opening of the inner and outer secondary air dampers of the burner, the wind speed of the primary air nozzle of the burner, and the wind speed of the inner and outer secondary air nozzles of the burner, and judge whether the boiler is in a cold shutdown period of the boiler; an inspection and testing module, which is used to inspect the nozzle shape of the burner and the opening of the inner and outer secondary air dampers of the burner when the boiler is in a cold shutdown period of the boiler, and to grid test and inspect the wind speed of the primary air nozzle of the burner and the wind speed of the inner and outer secondary air nozzles of the burner to obtain the inspection result of the burner; a positioning and control module, which is used to formulate a high-temperature corrosion prevention and control strategy according to the inspection result of the burner, so as to locate and control the cause of high-temperature corrosion in the nozzle area of ​​the counter-combustion boiler burner.

[0015] In a third aspect, an embodiment of the present invention provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program is executed by the processor, any step of a method for improving high-temperature corrosion in the nozzle area of ​​a burner of a hedge combustion boiler as described in the first aspect of the present invention is implemented.

[0016] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, any step of a method for improving high-temperature corrosion in the nozzle area of ​​a burner of a counter-combustion boiler as described in the first aspect of the present invention is implemented.

[0017] Beneficial effects of the invention: The invention proposes a method for improving high-temperature corrosion in the burner nozzle area of ​​a counter-firing boiler, which can effectively avoid the shortcomings of passive methods such as traditional water-cooled wall anti-corrosion spraying, locate the causes of high-temperature corrosion in the burner nozzle area from the source, and conduct targeted adjustments and treatments, thereby effectively solving the high-temperature corrosion problem in the burner nozzle area. It has strong pertinence and significant effects, and is a fundamental method for solving the high-temperature corrosion problem in the burner nozzle area of ​​a counter-firing boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0019] Figure 1 This is an overall flow chart of a method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner in Example 1.

[0020] Figure 2 This is the fireworks tracing effect diagram of the A4 burner in Example 2. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0022] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0023] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0024] Example 1

[0025] Reference Figure 1 , which is the first embodiment of the present invention, provides a method for improving high temperature corrosion in the nozzle area of ​​a burner of a hedge combustion boiler.

[0026] The existing methods for preventing and controlling high-temperature corrosion in the burner nozzle area mainly have the following problems: First, the water-cooled wall anti-corrosion spraying commonly used in existing power plants is a passive protection method. The spraying effect lasts for a short time and requires frequent repeated spraying, which increases maintenance costs and downtime. It is impossible to diagnose and treat the root cause of high-temperature corrosion, resulting in repeated high-temperature corrosion problems in the burner nozzle area; secondly, existing monitoring and prevention measures are often limited to the observation of a single parameter and lack an overall grasp of the combustion process; in addition, traditional inspection methods mostly rely on regular shutdowns and maintenance, which makes it difficult to detect and deal with problems in a timely manner. In terms of burner adjustment, existing technologies often use empirical adjustment methods and lack scientific and systematic optimization strategies; finally, existing technologies generally lack accurate measurement and analysis of the airflow distribution in the burner nozzle area, which makes it difficult to accurately locate and solve the root cause of the high-temperature corrosion problem, and cannot fundamentally solve the high-temperature corrosion problem in the burner nozzle area.

[0027] The present application provides an effective solution to the above-mentioned problems. Next, a plurality of embodiments will be combined to explain in detail how to implement the method for improving high-temperature corrosion in the nozzle area of ​​the burner of a hedge combustion boiler.

[0028] Figure 1 The overall flow chart of a method for improving high temperature corrosion in the nozzle area of ​​a hedge-fired boiler burner is shown, comprising:

[0029] S1: Obtain relevant data of the boiler and make a status judgment. If the boiler is in a cold shutdown period, check the burner.

[0030] Preferably, the boiler related data includes the operating status of the boiler, the shape of the burner nozzle, the opening of the inner and outer secondary air doors of the burner, the wind speed of the burner primary air nozzle, and the wind speed of the inner and outer secondary air nozzles of the burner.

[0031] Furthermore, the state judgment refers to judging the operating state of the boiler, analyzing whether the boiler is in a period of boiler cold shutdown or a period of boiler hot operation.

[0032] Preferably, by comprehensively collecting the operating data of the boiler, including whether the boiler is running, the nozzle shape of the burner, the damper opening and the wind speed, the high-temperature corrosion prevention stage of the burner nozzle area of ​​the hedge combustion boiler can be accurately determined, and then a targeted high-temperature corrosion prevention strategy can be formulated.

[0033] S2: Based on the inspection of the burner, the nozzle shape of the burner and the internal and external secondary air dampers of the burner are inspected, and the primary air velocity of the burner nozzle and the internal and external secondary air velocities of the burner nozzle are grid tested and inspected to obtain the inspection results of the burner.

[0034] Preferably, checking the shape of the burner nozzle includes checking the burning condition of the burner expansion cone, the burning condition of the stabilizing teeth, the blockage of the primary air duct of the burner nozzle, the blockage of the secondary air duct of the burner nozzle and the coking condition of the burner nozzle.

[0035] Furthermore, checking the internal and external secondary air dampers of the burner includes: during cold shutdown of the boiler, checking the original openings of the internal and external secondary air dampers of the burner.

[0036] Enter the bellows and check the actual opening of the inner and outer secondary air doors.

[0037] Ensure that the inner and outer secondary air doors are flexible and adjustable to avoid sticking.

[0038] During the hot operation of the boiler, the internal and external secondary air volume and swirl intensity of the burner are adjusted and optimized to increase the internal and external secondary air volume of the burner and reduce the swirl intensity.

[0039] Specifically, the grid test and inspection of the primary wind speed at the burner nozzle includes performing grid method wind speed tests on the upper, lower, left and right positions of the burner primary air nozzle under cold ventilation conditions, to determine whether there is a local area in the upper, lower, left or right position of the burner primary air nozzle with a wind speed ≤ a first threshold, and to locate the cause of high temperature corrosion in the burner nozzle area of ​​the hedge combustion boiler.

[0040] Specifically, the grid test and inspection of the internal and external secondary air velocities of the burner nozzle include: under cold ventilation conditions, grid method wind speed tests are performed on the upper, lower, left and right positions of the secondary air nozzle inside the burner and the secondary air nozzle outside the burner to determine whether there is a local area in the upper, lower, left or right position of the secondary air nozzle inside the burner where the wind speed is ≤ a second threshold.

[0041] Determine whether there is a local area in the upper, lower, left or right position of the secondary air nozzle outside the burner where the wind speed is ≤ the third threshold.

[0042] Based on the judgment results of the secondary air nozzles inside the burner and the secondary air nozzles outside the burner, the cause of high-temperature corrosion in the nozzle area of ​​the hedge combustion boiler burner is located.

[0043] It should be noted that when conducting grid tests on the primary wind speed and internal and external secondary wind speeds of the burner nozzle, N measuring points can be selected at the upper, lower, left and right positions of the primary air nozzle of the burner, the secondary air nozzle inside the burner and the secondary air nozzle outside the burner to form an N×N grid. Multiple measurements are performed at each measuring point and the average value is taken. The wind speed data of each measuring point is recorded, and a wind speed distribution diagram is drawn. Then, a judgment is made based on different thresholds and the analysis results of the wind speed distribution diagram to check whether there are local areas below the threshold.

[0044] Preferably, by using a grid test method to accurately detect the primary wind speed and the internal and external secondary wind speeds of the burner nozzle, it is possible to detect wind speed anomalies in local areas and accurately locate the abnormal wind speed areas, thereby promptly discovering and solving potential problems, improving the accuracy of detection, and avoiding local anomalies that may be overlooked by traditional methods; it helps to promptly discover foreign matter or other abnormal conditions in the upstream channel of the burner nozzle, reducing the risk of equipment failure and high-temperature corrosion. Compared with the sampling or average value measurement methods commonly used in the prior art, the grid test method used in the present invention can comprehensively and accurately reflect the wind speed conditions of various parts of the burner, thereby improving the accuracy and coverage of detection.

[0045] S3: Develop a high-temperature corrosion prevention and control strategy based on the burner inspection results to locate and control high-temperature corrosion in the burner nozzle area of ​​the hedge combustion boiler.

[0046] Preferably, formulating a high-temperature corrosion prevention and control strategy includes the following steps: when the boiler is in a cold shutdown period, the shape of the burner nozzle is checked, and the burned and deformed parts are repaired in time. If the burner has cone expansion burnout, combustion stabilizing tooth burnout, burner nozzle primary air duct blockage, burner nozzle secondary air duct blockage or burner nozzle coking, notify the power plant maintenance personnel to eliminate the fault.

[0047] Otherwise, it is determined that the nozzle shape of the burner is normal and the next step is executed.

[0048] During the cold shutdown of the boiler, check the flexibility of the internal and external secondary air dampers of the burner to ensure that the internal and external secondary air dampers of the burner are flexibly adjustable to avoid sticking.

[0049] Check the opening of the inner and outer secondary air dampers of the burner by checking their original openings and entering the bellows to verify their actual openings. If the original openings of the inner and outer secondary air dampers are not equal to their actual openings, notify the power plant maintenance personnel to inspect the inner and outer secondary air dampers.

[0050] If the original opening of the inner and outer secondary air doors = the actual opening of the inner and outer secondary air doors, it is determined that the accuracy of the inner and outer secondary air doors of the burner is good, and the next step is executed.

[0051] Under cold ventilation conditions, grid method wind speed tests are performed on the upper, lower, left and right positions of the primary air nozzle of the burner to avoid low wind speed in local areas. If there is a local area with wind speed ≤ the first threshold value in the upper, lower, left or right positions of the primary air nozzle of the burner, check whether there are foreign objects in the primary channel upstream of the burner nozzle. If there are foreign objects, notify the power plant maintenance personnel to eliminate the fault.

[0052] If there is no foreign matter, it is determined that there is an abnormality in the boiler and the power plant maintenance personnel are notified to inspect the boiler.

[0053] If the wind speed in all areas above, below, left or right of the primary air nozzle of the burner is greater than the first threshold, it is determined that the primary passage upstream of the burner nozzle is normal, and the next step is executed.

[0054] Under cold ventilation conditions, grid method wind speed tests are performed on the upper, lower, left and right positions of the secondary air nozzles inside and outside the burner to avoid local areas with too low wind speed and too strong suction. If there is a local area with wind speed ≤ the second threshold value in the upper, lower, left or right positions of the secondary air nozzles in the burner, check whether there are foreign objects in the secondary duct upstream of the secondary air nozzles in the burner. If there are foreign objects, notify the power plant maintenance personnel to eliminate the fault.

[0055] If there is no foreign matter, it is determined that there is an abnormality in the boiler and the power plant maintenance personnel are notified to inspect the boiler.

[0056] If the wind speed in all areas at the upper, lower, left or right position of the secondary air nozzle in the burner is greater than the second threshold, it is determined that the secondary passage upstream of the secondary air nozzle in the burner is normal.

[0057] If there is a local area with a wind speed ≤ the third threshold value in the upper, lower, left or right position of the secondary air nozzle outside the burner, check whether there are foreign objects in the secondary passage upstream of the secondary air nozzle outside the burner. If there are foreign objects, notify the power plant maintenance personnel to eliminate the fault.

[0058] If there is no foreign matter, it is determined that there is an abnormality in the boiler and the power plant maintenance personnel are notified to inspect the boiler.

[0059] If the wind speed in all areas above, below, left or right of the secondary air nozzle outside the burner is greater than the third threshold, it is determined that the secondary path upstream of the secondary air nozzle outside the burner is normal, and the next step is executed.

[0060] After the fault elimination process is completed, a cold fireworks tracer test is conducted on the boiler to simulate and evaluate the combustion status of the burner nozzle.

[0061] After the inspection of the burner during the cold shutdown period of the boiler is completed, when the boiler is in hot operation, based on the inspection results of the burner during the cold shutdown period of the boiler, the internal and external secondary air dampers of the burner are adjusted to determine the appropriate internal and external secondary air volume and suction intensity, increase the internal and external secondary air volume of the burner, reduce the swirl intensity, and solve the problem of high-temperature corrosion of the water-cooled wall below the burner nozzle.

[0062] Furthermore, adjusting the internal and external secondary air dampers of the burner means increasing the internal and external secondary air volume of the burner while ensuring uniform combustion along the width of the furnace, in combination with the powder distribution of the powder pipe during hot operation of the boiler.

[0063] It should be noted that before conducting the cold fireworks tracer test, it is necessary to ensure that the boiler is in a cold shutdown state, keep the ventilation system running, and prepare a non-toxic, low-temperature and moderate-duration fireworks tracer. When conducting the cold fireworks tracer test, it is necessary to simulate different damper openings and wind speed conditions, and conduct multiple repeated tests under each condition. By installing a high-speed camera, the smoke flow trajectory is captured and analyzed, the burner's suction effect and swirl intensity are evaluated, and the smoke diffusion under different wind speeds and opening conditions is compared. Finally, the best parameter combination is determined, and then based on the smoke trajectory, the flame shape and distribution during actual combustion are inferred. Combined with the grid test results, potential high-temperature areas and locations where corrosion may occur are evaluated, and the burner performance and possible problems are comprehensively analyzed.

[0064] Preferably, differentiated high-temperature corrosion prevention strategies are formulated for different operating states of the boiler, including the cold shutdown period of the boiler and the hot operation period of the boiler, and the most appropriate prevention and control measures are taken for different operating states, thereby improving the flexibility and efficiency of high-temperature corrosion prevention and control and avoiding unnecessary maintenance and adjustments. During the cold shutdown period of the boiler, a comprehensive inspection of the burner nozzle shape, air door opening and wind speed can be carried out to timely discover and repair potential problems, thereby improving the reliability of the equipment; during the hot operation of the boiler, the internal and external secondary air doors are adjusted to increase the internal and external secondary air volume and reduce the swirl intensity, while maintaining While ensuring uniform combustion of powder in the powder pipe, it solves the problem of high-temperature corrosion, effectively locates and solves the problem of high-temperature corrosion of the water-cooled wall below the burner nozzle; compared with traditional methods that usually rely on hot tests or theoretical calculations, the present invention adopts cold fireworks tracer tests to provide a safe, economical and intuitive evaluation method, creatively applying technologies from other fields to boiler maintenance. Without the need for actual combustion, it can intuitively observe and evaluate the performance of the burner and the combustion state of the nozzle, which helps to verify the effect of the early adjustment of the boiler, provide a basis for subsequent optimization, and reduce the risk of actual operation of the boiler.

[0065] The present embodiment also provides a system for improving high-temperature corrosion in the nozzle area of ​​a counter-combustion boiler burner, including: an operating status module, which is used to obtain the operating status of the boiler, the nozzle shape of the burner, the opening of the inner and outer secondary air dampers of the burner, the wind speed of the primary air nozzle of the burner, and the wind speed of the inner and outer secondary air nozzles of the burner, and to determine whether the boiler is in a cold shutdown period of the boiler; an inspection and testing module, which is used to inspect the nozzle shape of the burner and the opening of the inner and outer secondary air dampers of the burner when the boiler is in a cold shutdown period of the boiler, and to perform grid testing and inspection on the wind speed of the primary air nozzle of the burner and the wind speed of the inner and outer secondary air nozzles of the burner to obtain the inspection result of the burner; a positioning and control module, which is used to formulate a high-temperature corrosion prevention and control strategy according to the inspection result of the burner, so as to locate and control the cause of high-temperature corrosion in the nozzle area of ​​the counter-combustion boiler burner.

[0066] This embodiment also provides a computer device, which is suitable for a method of improving high-temperature corrosion in the nozzle area of ​​a hedge combustion boiler burner, including: a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute computer executable instructions to implement a method of improving high-temperature corrosion in the nozzle area of ​​a hedge combustion boiler burner as proposed in the above embodiment.

[0067] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0068] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, a method for improving high-temperature corrosion in the nozzle area of ​​a burner of a hedge combustion boiler as proposed in the above embodiment is implemented; the storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (Static Random Access Memory, referred to as SRAM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, referred to as EEPROM), erasable programmable read-only memory (Erasable Programmable Read Only Memory, referred to as EPROM), programmable read-only memory (Programmable Red-Only Memory, referred to as PROM), read-only memory (Read-Only Memory, referred to as ROM), magnetic storage, flash memory, magnetic disk or optical disk.

[0069] In summary, the present invention proposes a method for improving high-temperature corrosion in the burner nozzle area of ​​a counter-firing boiler, which can effectively avoid the shortcomings of passive methods such as traditional water-cooled wall anti-corrosion spraying, locate the causes of high-temperature corrosion in the burner nozzle area from the source, and carry out targeted adjustments and treatments, thereby effectively solving the high-temperature corrosion problem in the burner nozzle area. It has strong pertinence and significant effects, and is a fundamental method for solving the high-temperature corrosion problem in the burner nozzle area of ​​a counter-firing boiler.

[0070] Example 2

[0071] Reference Figure 2, which is the second embodiment of the present invention. This embodiment is different from the first embodiment in that, in order to verify its beneficial effects, experimental comparison data between the present invention and the prior art are provided.

[0072] This example uses a supercritical coal-fired boiler produced by a certain company, model DG1900 / 25.4-Ⅱ2. The supercritical coal-fired boiler is a wall-type combustion hedging supercritical parameter transformer DC furnace, that is, a single furnace, one-time reheating, balanced ventilation, open-air layout, solid slag discharge, all-steel frame and fully suspended structure Ⅱ type boiler. The supercritical coal-fired boiler adopts a positive pressure direct blowing pulverizing system and is equipped with six HP-1003 medium-speed coal mills. Each coal mill corresponds to a layer of burners. The burners adopt front and rear wall hedging graded combustion technology. Low NOx swirl HT-NR3 pulverized coal burners are arranged in three layers on the front and rear walls of the furnace, with 6 burners on each layer. There are 36 burners in the whole furnace.

[0073] During the boiler maintenance, it was found that there was severe high-temperature corrosion below the nozzles of the A2, A3, A4 and A5 burners in the lower burners of the front wall of the supercritical coal-fired boiler, which seriously affected the safe operation of the unit. The problem was solved by using the method proposed in the present invention.

[0074] Based on the method proposed in the present invention, during the cold shutdown of the boiler, the nozzle shapes of the A2, A3, A4 and A5 burners are inspected. Through the inspection, it is found that the stabilizing rings of the A2 and A3 burners are burned, and the stabilizing teeth of the A3 and A4 burners are incomplete. The power plant maintenance personnel are notified to eliminate the faults.

[0075] After processing the nozzle shape of the burner, the original openings of the internal and external secondary air dampers of the A-layer burner were checked. The inspection results showed that the internal and external secondary air dampers of the A2, A3 and A4 burners had small openings. When the internal and external secondary air dampers were small, the secondary air swirl was strong and the secondary air trajectory would diverge to the surroundings. When the damper opening was too small, there would even be a wall brushing situation. The original openings of the internal and external secondary air dampers of the A-layer burner are shown in Table 1.

[0076] Table 1 Original opening position of the secondary air dampers inside and outside the A-layer burner during cold shutdown of the boiler

[0077]

[0078] After processing the internal and external secondary air dampers of the burner, the primary air velocity of the burner nozzle was grid tested and inspected. Under cold ventilation conditions, the primary air nozzle wind speed of the A layer burner was tested, and the primary air volume was set to 80t / h. To ensure the accuracy of the primary air velocity test of the burner nozzle, the test was carried out at the upper, lower, left and right positions of the primary air nozzle section. During the test, it was found that the primary air nozzles of the A3 and A5 burners had a large deviation in the cross-sectional wind velocity. The wind speed in the left and right areas of the nozzle section was 20m / s, and the wind speed in the upper area of ​​the nozzle was 28m / s, but the primary wind velocity in the lower area was only 3-8m / s. After the test, the primary air nozzles of the A3 and A5 burners were internally inspected, and it was found that there were foreign objects in the lower position of the primary air nozzle, which affected the uniformity of the primary air velocity of the cross section. During hot operation, the bottom supporting capacity of the coal powder of the nozzle was insufficient, which would cause high-temperature corrosion and erosion wear of the lower water-cooled wall, and the combustible content of the slag would also increase, affecting the safety and economy of the boiler operation.

[0079] After the power plant maintenance personnel cleaned up the foreign objects in the primary air nozzles of the A3 and A5 burners, they retested the wind speed of the primary air nozzles of the A3 and A5 burners. The retest results showed that the lower wind speed of the primary air nozzle of the A3 burner increased to about 18m / s, and the lower wind speed of the primary air nozzle of the A5 burner increased to about 17m / s. Although the lower wind speed of the primary air nozzle was still slightly lower than the upper wind speed of the primary air nozzle, the primary wind speed of the nozzles of the A3 and A5 burners was basically normal.

[0080] After processing the primary wind speed of the burner nozzle, the internal and external secondary wind speeds of the burner nozzle were grid tested and checked. Under cold ventilation conditions, the internal and external secondary air nozzle wind speeds of the six burners on the A layer were tested. The test results are shown in Table 2.

[0081] Table 2 Test table of the wind speed of the inner secondary air and outer secondary air nozzles of the six burners in layer A

[0082] Tube No. A1 A2 A3 A4 A5 A6 Internal secondary air nozzle velocity (m / s) 16.5 7.8 5.0 3.8 11.8 17.8 External secondary air nozzle velocity (m / s) 28.3 25.3 26.8 23.8 25.8 23.0

[0083] It can be seen from Table 1 and Table 2 that the wind speed of the internal secondary air nozzle of A2, A3 and A4 burners is low when they are in the fully closed position. Therefore, it is recommended to appropriately increase the opening of the internal secondary air damper of A2, A3 and A4 burners during hot operation of the boiler.

[0084] After the boiler is fault-free, in order to visually evaluate the combustion status of the burner, a cold fireworks tracer test is performed on the A4 burner. Figure 2The figure shows the fireworks tracing effect of the A4 burner. It can be seen from the figure that when the inner secondary air damper of the burner is fully closed and the outer secondary air is 15%, the flame brushes the wall, which is consistent with the high-temperature corrosion of the water-cooled wall below the nozzles of the #3 to #5 burners in the A layer. Therefore, it is recommended to avoid too small opening of the inner and outer secondary air dampers during hot operation of the boiler.

[0085] As shown in Table 3, the optimized position of the internal and external secondary air door opening of the A-layer burner after adjustment during the hot operation of the boiler, during the hot operation of the boiler, the internal and external secondary air of the A-layer burner was adjusted to appropriately increase the internal and external secondary air while ensuring uniform combustion along the width of the furnace by combining the powder distribution of the powder pipe.

[0086] Table 3 Optimized position of the internal and external secondary air damper opening of the A-layer burner during hot operation of the boiler

[0087]

[0088] After a series of inspections and adjustments based on the above method, it was found that the problem of high-temperature corrosion of the water-cooled wall below the burner nozzle of layer A was completely solved, and the reason for multiple shutdowns and maintenance was the discovery of the high-temperature corrosion problem, indicating that the present invention can effectively solve the high-temperature corrosion problem in the burner nozzle area.

[0089] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner, characterized in that: include: Obtain relevant data of the boiler and make status judgment. If the boiler is in the cold shutdown period, check the burner; Based on the inspection of the burner, the shape of the burner nozzle and the internal and external secondary air dampers of the burner are inspected, and the primary air velocity of the burner nozzle and the internal and external secondary air velocities of the burner nozzle are grid tested and inspected to obtain the inspection result of the burner; Based on the inspection results of the burner, a high-temperature corrosion prevention and control strategy is formulated to locate and control high-temperature corrosion in the nozzle area of ​​the hedge combustion boiler burner.

2. The method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner according to claim 1, characterized in that: The boiler related data includes the operating status of the boiler, the shape of the burner nozzle, the opening of the inner and outer secondary air doors of the burner, the wind speed of the primary air nozzle of the burner, and the wind speed of the inner and outer secondary air nozzles of the burner; The state judgment refers to judging the operating state of the boiler, and analyzing whether the boiler is in a cold shutdown period or a hot operation period.

3. The method for improving high temperature corrosion in the nozzle area of ​​a counter-fired boiler burner according to claim 2, characterized in that: The high temperature corrosion prevention strategy comprises the following steps: When the boiler is in cold shutdown, check the shape of the burner nozzle. If the burner has cone expansion burnout, combustion stabilizing teeth burnout, primary air duct blockage, secondary air duct blockage or coking at the burner nozzle, notify the power plant maintenance personnel to eliminate the fault. Otherwise, it is determined that the nozzle shape of the burner is normal, and the next step is executed; During the cold shutdown of the boiler, check the flexibility of the internal and external secondary air dampers of the burner to ensure that the internal and external secondary air dampers of the burner are flexible and adjustable; Check the opening of the internal and external secondary air dampers of the burner. Check the original opening of the internal and external secondary air dampers of the burner and enter the wind box to check the actual opening of the internal and external secondary air dampers. If the original opening of the internal and external secondary air dampers is not equal to the actual opening of the internal and external secondary air dampers, notify the maintenance personnel of the power plant to inspect the internal and external secondary air dampers. If the original opening of the inner and outer secondary air valves = the actual opening of the inner and outer secondary air valves, it is determined that the accuracy of the inner and outer secondary air valves of the burner is good, and the next step is executed; Under cold ventilation conditions, perform grid method wind speed test on the upper, lower, left and right positions of the primary air nozzle of the burner. If the wind speed of a local area in the upper, lower, left or right position of the primary air nozzle of the burner is less than or equal to the first threshold, check whether there is foreign matter in the primary channel upstream of the burner nozzle. If there is foreign matter, notify the power plant maintenance personnel to eliminate the fault; If there is no foreign matter, it is determined that the boiler is abnormal, and the power plant maintenance personnel are notified to inspect the boiler; If the wind speed of all areas in the upper, lower, left or right position of the primary air nozzle of the burner is greater than the first threshold, it is determined that the primary air passage upstream of the burner nozzle is normal, and the next step is executed; Under cold ventilation conditions, perform grid method wind speed tests on the upper, lower, left and right positions of the secondary air nozzles inside and outside the burner. If the wind speed in a local area in the upper, lower, left or right position of the secondary air nozzles inside the burner is ≤ the second threshold, check whether there are foreign objects in the secondary passage upstream of the secondary air nozzles inside the burner. If there are foreign objects, notify the power plant maintenance personnel to eliminate the fault; If there is no foreign matter, it is determined that the boiler is abnormal, and the power plant maintenance personnel are notified to inspect the boiler; If the wind speed of all areas in the upper, lower, left or right position of the secondary air nozzle in the burner is greater than the second threshold, it is determined that the secondary path upstream of the secondary air nozzle in the burner is normal; If the wind speed in a local area at the upper, lower, left or right position of the secondary air nozzle outside the burner is less than or equal to the third threshold, check whether there is foreign matter in the secondary passage upstream of the secondary air nozzle outside the burner. If there is foreign matter, notify the power plant maintenance personnel to eliminate the fault; If there is no foreign matter, it is determined that the boiler is abnormal, and the power plant maintenance personnel are notified to inspect the boiler; If the wind speed of all areas in the upper, lower, left or right position of the secondary air nozzle outside the burner is greater than the third threshold, it is determined that the secondary path upstream of the secondary air nozzle outside the burner is normal, and the next step is executed; After the fault elimination process, the boiler is subjected to a cold fireworks tracer test to simulate and evaluate the combustion state of the burner nozzle; After the inspection of the burner during the cold shutdown of the boiler is completed, when the boiler is in hot operation, the internal and external secondary air dampers of the burner are adjusted based on the inspection results of the burner during the cold shutdown of the boiler to determine the internal and external secondary air volume and suction intensity.

4. The method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner according to claim 3, characterized in that: Inspection of the burner nozzle shape includes inspection of the burner expansion cone burning condition, the combustion stabilizing teeth burning condition, the burner nozzle primary air duct blockage condition, the burner nozzle secondary air duct blockage condition and the burner nozzle coking condition.

5. The method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner according to claim 4, characterized in that: Inspection of the internal and external secondary air doors of the burner includes: During cold shutdown of the boiler, check the original opening of the internal and external secondary air dampers of the burner; Enter the bellows and check the actual opening of the internal and external secondary air doors; Ensure that the internal and external secondary air doors are flexible and adjustable; During the hot operation of the boiler, the internal and external secondary air volume and swirl intensity of the burner are adjusted and optimized.

6. The method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner according to claim 5, characterized in that: The grid test and inspection of the primary air velocity of the burner nozzle refers to the grid method wind velocity test of the upper, lower, left and right positions of the primary air nozzle of the burner under cold ventilation conditions; Grid testing and inspection of the internal and external secondary air velocities of the burner nozzles refers to conducting grid method wind speed tests on the upper, lower, left and right positions of the secondary air nozzles inside the burner and the secondary air nozzles outside the burner under cold ventilation conditions.

7. The method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner according to claim 6, characterized in that: The adjustment of the internal and external secondary air dampers of the burner refers to increasing the internal and external secondary air volume of the burner while ensuring uniform combustion along the width of the furnace, in combination with the powder distribution of the powder pipe during hot operation of the boiler.

8. A system for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner, based on a method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner according to any one of claims 1 to 7, characterized in that: include, The operation status module is used to obtain the operation status of the boiler, the shape of the burner nozzle, the opening of the internal and external secondary air doors of the burner, the wind speed of the primary air nozzle of the burner, and the wind speed of the internal and external secondary air nozzles of the burner, and to determine whether the boiler is in the boiler cold shutdown period; The inspection and testing module is used to inspect the nozzle shape of the burner and the opening of the internal and external secondary air doors of the burner when the boiler is in a cold shutdown period, and to perform grid testing and inspection on the wind speed of the primary air nozzle of the burner and the wind speed of the internal and external secondary air nozzles of the burner to obtain the inspection results of the burner; The positioning and control module is used to formulate high-temperature corrosion prevention and control strategies based on the inspection results of the burner, and to locate and control the causes of high-temperature corrosion in the nozzle area of ​​the burner of the hedge combustion boiler.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of a method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of a method for improving high temperature corrosion in the nozzle area of ​​a counter-firing boiler burner as described in any one of claims 1 to 7 are implemented.

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