An automatic adjustment method and system for the flue gas temperature deviation at the boiler furnace outlet

Abstract

The present invention belongs to the technical field of temperature control, and provides an automatic adjustment method and system for the flue gas temperature deviation at the boiler furnace outlet. During adjustment, according to the flue gas temperature deviation situation, the opening degree of the burnout air damper and the bias angle of the burnout air are adjusted in a preset order and amplitude; the adjusted flue gas temperature deviation is obtained; continue to compare the oxygen content deviation in the flue gas before and after adjustment. If the oxygen content deviation exceeds the preset oxygen content limit value, the secondary air damper is adjusted in a preset ratio and amplitude until the oxygen content deviation is within the preset oxygen content limit value; continue to judge whether the adjusted flue gas temperature deviation is reduced to within the preset temperature deviation limit value to determine whether to continue the judgment and adjustment. Through the above adjustment process, the automatic adjustment of the burnout air damper and the secondary air damper is realized according to the flue gas temperature deviation situation, thereby solving the problems of long time consumption and poor adjustment effect during manual adjustment, and realizing the elimination of the phenomenon of large flue gas temperature deviation at the furnace outlet.

Description

Technical Field

[0001] The present invention belongs to the technical field of temperature control, and particularly relates to an automatic adjustment method and system for the flue gas temperature deviation at the boiler furnace outlet. Background Art

[0002] In a thermal power plant, during the operation of a boiler, the situation of large flue gas temperature deviation at the furnace outlet often occurs. Seriously, it causes a large difference in the main steam temperature on both sides, exceeding the allowable range, directly affecting the operation safety and economic benefits.

[0003] The inventor found that usually, power plant operators would manually adjust the air distribution at all levels to try to eliminate the phenomenon of large flue gas temperature deviation at the furnace outlet. Not only does the adjustment process take a long time and the adjustment effect is poor, but also the experience and specific operation methods of each shift and each specific operator are different. The personal level and experience of the operator have a very important impact on the adjustment process and results. Different operators will also have different results when adjusting at different times. The operation process is relatively arbitrary, the adjustment effect is unstable, and sometimes it will even increase the deviation. Moreover, frequent adjustment will also have a serious impact on the stable combustion of the boiler, thus affecting the economy and safety of the unit. Summary of the Invention

[0004] To solve the above problems, the present invention proposes an automatic adjustment method and system for the flue gas temperature deviation at the boiler furnace outlet. The present invention adopts the method of adjusting the forward and reverse tangential air, directly adding a temperature adjustment control logic module in the Distributed Control System (DCS for short). According to the flue gas temperature deviation situation, it can select the automatic or manual mode. First, judge the parameters, and then adjust the angles and air volumes of the forward tangential air or reverse tangential air. At the same time, couple parameters such as oxygen content, continuously judge and adjust with a time delay, and automatically reduce the flue gas temperature deviation to the allowable range gradually while keeping other parameters from changing greatly, so as to reduce the steam temperature deviation. And the automatic adjustment control of the baffle will also play a beneficial role in improving the boiler combustion efficiency and reducing the emission of nitrogen oxides (NOx).

[0005] To achieve the above object, the present invention is realized through the following technical solutions:

[0006] In the first aspect, the present invention provides an automatic adjustment method for the flue gas temperature deviation at the boiler furnace outlet, including:

[0007] Obtain the flue gas temperatures on both sides of the furnace outlet;

[0008] Calculate the flue gas temperature deviation on both sides according to the obtained flue gas temperatures on both sides;

[0009] Judge whether the flue gas temperature deviation exceeds a preset limit value. If so, perform adjustment; otherwise, do not adjust;

[0010] If the flue gas temperature deviation exceeds the preset limit value of the temperature deviation, according to the flue gas temperature deviation situation, adjust the opening degree of the overfire air damper and the bias angle of the overfire air in the preset order and amplitude to obtain the adjusted flue gas temperature deviation and the oxygen content in the flue gas;

[0011] Continue to compare the oxygen content deviation in the flue gas before and after adjustment. If the oxygen content deviation exceeds the preset limit value of the oxygen content, adjust the secondary air damper according to the preset ratio and amplitude until the oxygen content deviation is within the preset limit value of the oxygen content;

[0012] Continue to obtain and compare whether the flue gas temperature deviation on both sides is reduced to within the preset limit value of the temperature deviation. If so, stop the adjustment; otherwise, continue to make judgments and adjustments until the flue gas temperature deviation is reduced to within the preset limit value of the temperature deviation.

[0013] Further, when opening the overfire air damper, within the preset opening increment range, open it in sequence from the upper layer to the lower layer. When the overfire air damper is opened to the limit value, adjust and open the bias angle of each layer of overfire air from top to bottom in the preset amplitude each time. Calculate and judge once for each adjustment of the damper or the bias angle until the adjustment requirements are met;

[0014] When adjusting and closing the overfire air damper, within the preset opening increment range, close each layer of overfire air damper in sequence from the upper layer to the lower layer. When the overfire air damper is closed to the limit value, adjust and close the bias angle of each layer of overfire air from top to bottom in the preset amplitude each time. Calculate and judge once for each adjustment of the damper or the bias angle until the adjustment requirements are met.

[0015] Further, when opening the secondary air damper, within the preset opening increment range, open each layer of secondary air damper in sequence from the upper layer to the lower layer;

[0016] When adjusting and closing the secondary air damper, within the preset opening increment range, close each layer of secondary air damper in sequence from the upper layer to the lower layer;

[0017] Calculate and judge once for each adjustment of a layer until the adjustment requirements for the oxygen content are met.

[0018] Further, keep the change in the oxygen content of the flue gas within the preset allowable range during the adjustment.

[0019] Further, if the flue gas temperature on one side of the furnace outlet is greater than that on the other side, that is, the temperature distribution from high to low is clockwise, it is judged whether the opening degree of the burnout air damper is greater than the first preset limit opening degree. If so, the reverse-cut burnout air is closed by a preset ratio, otherwise, an alarm is given; if the flue gas temperature on one side of the furnace outlet is less than that on the other side, that is, the temperature distribution from high to low is counterclockwise, it is judged whether the opening degree of the burnout air damper is greater than the second preset limit opening degree. If so, an alarm is given, otherwise, the reverse-cut burnout air is opened by a preset ratio.

[0020] Further, it is judged whether the oxygen content in the flue gas before regulation is greater than that in the flue gas after regulation. If so, the secondary air damper is opened in layers by a preset ratio and sequence, otherwise, the secondary air is closed by a preset ratio and sequence.

[0021] Further, the adjustment sequence, adjustment amplitude, adjustment size limit, and adjustment speed of the burnout air damper and the secondary air damper are adjustable.

[0022] In a second aspect, the present invention further provides an automatic adjustment system for the flue gas temperature deviation at the boiler furnace outlet, including:

[0023] A data acquisition module configured to: obtain the flue gas temperatures on both sides of the furnace outlet;

[0024] A temperature deviation calculation module configured to: calculate the flue gas temperature deviation between the two sides based on the obtained flue gas temperatures on both sides;

[0025] A first judgment module configured to: judge whether the flue gas temperature deviation exceeds a preset limit. If so, adjustment is performed, otherwise, no adjustment is made;

[0026] A first adjustment module configured to: if the flue gas temperature deviation exceeds the preset temperature deviation limit, adjust the opening degree of the burnout air damper and the offset angle of the burnout air according to the flue gas temperature deviation situation, in a preset order and amplitude; obtain the adjusted flue gas temperature deviation and flue gas oxygen content;

[0027] A second judgment module configured to: judge whether the adjusted flue gas oxygen content deviation exceeds a preset limit. If so, continue the adjustment, otherwise, stop the adjustment;

[0028] A second adjustment module configured to: when the adjusted flue gas oxygen content deviation exceeds the oxygen content preset limit, adjust the secondary air damper according to a preset ratio and amplitude until the oxygen content deviation is within the oxygen content preset limit;

[0029] A third judgment module, configured to: continue to obtain and compare whether the flue gas temperature deviation on both sides is reduced to within a preset limit value of the temperature deviation. If so, stop the adjustment; otherwise, continue to make judgments and adjustments until the flue gas temperature deviation is reduced to within the preset limit value of the temperature deviation.

[0030] In a third aspect, the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the steps of the method for automatically adjusting the flue gas temperature deviation at the furnace outlet of the boiler described in the first aspect are implemented.

[0031] In a fourth aspect, the present invention further provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps of the method for automatically adjusting the flue gas temperature deviation at the furnace outlet of the boiler described in the first aspect are implemented.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] 1. The present invention determines whether to make an adjustment by judging whether the flue gas temperature deviation exceeds a preset limit value. During the adjustment, according to the flue gas temperature deviation situation, the opening degree of the overfire air baffle and the bias angle of the overfire air are adjusted in a preset order and amplitude; the adjusted flue gas temperature deviation is obtained; continue to compare the oxygen content deviation in the flue gas before and after the adjustment. If the oxygen content deviation exceeds the preset limit value of the oxygen content, the secondary air baffle is adjusted in a preset ratio and amplitude until the oxygen content deviation is within the preset limit value of the oxygen content; continue to judge whether the adjusted flue gas temperature deviation is reduced to within the preset limit value of the temperature deviation to determine whether to continue to make judgments and adjustments; through the above adjustment process, the automatic adjustment of the overfire air baffle and the secondary air baffle is realized according to the flue gas temperature deviation situation, thus solving the problems of long time consumption and poor adjustment effect during manual adjustment, and realizing the elimination of the phenomenon of large flue gas temperature deviation at the furnace outlet.

[0034] 2. In addition to setting a new temperature adjustment control logic module in the DCS, the present invention uses the original equipment of the boiler for the rest of the temperature measurement, air damper, actuator equipment, etc. (usually, the overfire air baffle is located at the upper part of the boiler combustion area, and the secondary air baffle is located in the boiler burner area and is arranged staggered with the primary air of the burner). That is, there is no need to add or install additional equipment, which does not affect the entire system, is simple and reliable to implement, and has low investment and quick results.

[0035] 3. After the present invention is put into automatic operation, it can automatically adjust and control or maintain the flue gas temperature deviation within the allowable range by relying on the judgment of the logic module, eliminating the dependence on the quality and experience of the operating personnel for the control result, greatly reducing manual operation intervention, greatly reducing the workload of the operating personnel for operation adjustment, and enabling them to concentrate more on monitoring the changes of other important parameters, which is beneficial to the safe and economic operation of the unit.

[0036] 4. The present invention automatically adjusts and coordinately controls the baffle to achieve the purpose of adjusting the temperature difference, reduces the frequent manual operations, reduces the impact of adjustment operations on the entire system, and also has a beneficial effect on the stable combustion of the boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings forming a part of this embodiment are used to provide a further understanding of this embodiment. The schematic embodiments and descriptions thereof of this embodiment are used to explain this embodiment and do not constitute an improper limitation on this embodiment.

[0038] Figure 1 It is a judgment flowchart of Embodiment 1 of the present invention;

[0039] Figure 2 It is a flowchart of Embodiment 1 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0041] It should be noted that the following detailed descriptions are all exemplary and are intended to provide further descriptions of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0042] Note: The in-furnace gas flow tangential circle direction of the boiler is designed to be counterclockwise in some cases and clockwise in others, and the burnout air flow direction is generally designed to be opposite to the gas flow tangential circle, that is, counter-cut. The present invention will be described by taking the in-furnace gas flow tangential circle direction as counterclockwise and the burnout air flow direction as counter-cut as an example.

[0043] Embodiment 1:

[0044] As Figure 1 shown, this embodiment provides an automatic adjustment method for the flue gas temperature deviation at the furnace outlet of a boiler, including:

[0045] Obtain the flue gas temperatures on both sides of the furnace outlet;

[0046] Calculate the flue gas temperature deviation on both sides based on the obtained flue gas temperatures on both sides;

[0047] Judge whether the flue gas temperature deviation exceeds a preset limit value. If so, perform adjustment; otherwise, do not adjust;

[0048] If the flue gas temperature deviation exceeds the preset temperature deviation limit value, adjust the opening degree of the burnout air baffle and the offset angle of the burnout air according to the flue gas temperature deviation situation in a preset order and amplitude; obtain the adjusted flue gas temperature deviation and flue gas oxygen content;

[0049] Continue to compare the oxygen content deviation in the flue gas before and after adjustment. If the oxygen content deviation exceeds the preset limit of oxygen content, adjust the secondary air damper according to the preset ratio and amplitude until the oxygen content deviation is within the preset limit of oxygen content;

[0050] Continue to obtain and compare whether the flue gas temperature deviation on both sides is reduced to within the preset limit of temperature deviation. If so, stop the adjustment; otherwise, continue to judge and adjust until the flue gas temperature deviation is reduced to within the preset limit of temperature deviation.

[0051] When opening the overfire air damper, within the preset opening increment range, open it in sequence from the upper layer to the lower layer. When the overfire air damper is opened to the limit, adjust and open the bias angle of each layer of overfire air in sequence from top to bottom with the preset amplitude each time. Calculate and judge once for each adjustment of the damper or bias angle until the adjustment requirements are met;

[0052] When adjusting and closing the overfire air damper, within the preset opening increment range, close each layer of overfire air damper in sequence from the upper layer to the lower layer. When the overfire air damper is closed to the limit, adjust and close the bias angle of each layer of overfire air in sequence from top to bottom with the preset amplitude each time. Calculate and judge once for each adjustment of the damper or bias angle until the adjustment requirements are met. When opening the secondary air damper, within the preset opening increment range, open each layer of secondary air damper in sequence from the upper layer to the lower layer; when adjusting and closing the secondary air damper, within the preset opening increment range, close each layer of secondary air damper in sequence from the upper layer to the lower layer, and calculate and judge once for each adjustment until the adjustment requirements of the oxygen content are met.

[0053] If the flue gas temperature on one side of the furnace outlet is higher than that on the other side, that is, the temperature distribution from high to low is clockwise, judge whether the opening of the overfire air damper is greater than the first preset limit opening. If so, close the counter-rotating overfire air according to the preset ratio; otherwise, give an alarm. If the flue gas temperature on one side of the furnace outlet is lower than that on the other side, that is, the temperature distribution from high to low is counterclockwise, judge whether the opening of the overfire air damper is greater than the second preset limit opening. If so, give an alarm; otherwise, open the counter-rotating overfire air according to the preset ratio. Specifically, if the flue gas temperature on the left (or A) side of the furnace outlet is higher than that on the right (or B) side, that is, the temperature distribution from high to low is clockwise, judge whether the opening of the overfire air damper is greater than the first preset limit opening. If so, close the counter-rotating overfire air according to the preset ratio; otherwise, give an alarm. If the flue gas temperature on the left (or A) side of the furnace outlet is lower than that on the right (or B) side, that is, the temperature distribution from high to low is counterclockwise, judge whether the opening of the overfire air damper is greater than the second preset limit opening. If so, give an alarm; otherwise, open the counter-rotating overfire air according to the preset ratio.

[0054] Judge whether the oxygen content in the flue gas before adjustment is greater than that in the flue gas after adjustment. If so, open the secondary air damper in layers according to a preset ratio and sequence. Otherwise, close the secondary air damper according to a preset ratio and sequence.

[0055] In other embodiments, corresponding to the automatic adjustment method for the temperature deviation of the flue gas at the boiler furnace outlet, an automatic adjustment system for the temperature deviation of the flue gas at the boiler furnace outlet is also provided, including: a temperature adjustment control logic module is set in the DCS system, a temperature measuring device for the flue gas at the furnace outlet and an automatic adjustment device for the air damper. The temperature measuring device is a thermocouple installed on the flue duct. The automatic adjustment device for the air damper includes dampers such as overfire air dampers and secondary air dampers and their corresponding driving mechanisms. The dampers are located inside the boiler. The thermocouple and the driving mechanism are connected to the unit DCS system. The temperature of the flue gas at the furnace outlet of the flue duct is measured by the temperature measuring device, and the signal is transmitted to the temperature adjustment control logic module in the DCS. Deviation calculation is performed through the module. Then, according to the calculation result, an action instruction is issued to control the automatic adjustment device of the damper to coordinately control and adjust each damper. In a negative feedback manner, the flue gas temperature deviation is gradually reduced to the allowable range, so as to achieve the purpose of automatic temperature adjustment.

[0056] In the logic module, the steering selection of the tangential circle of the flue gas flow in the furnace under normal conditions can be set, and it can be selected to be clockwise or counterclockwise. In this embodiment, counterclockwise is taken as an example for illustration. The maximum allowable value of the flue gas temperature deviation on one side (marked as the left side or side A) and the other side (marked as the right side or side B) can be set, generally set to 50 °C.

[0057] Function selection is set in the logic module: such as turning on automatic / turning off automatic, selecting the air damper in the automatic / manual state, etc. Some dampers can be arbitrarily selected to participate in or withdraw from automatic adjustment. The adjustment sequence, adjustment amplitude, upper and lower limits of automatic adjustment and adjustment speed of the damper can be set, as well as the waiting time before each judgment of the module, etc. The air dampers include secondary air dampers, perimeter air dampers and overfire air dampers, etc.

[0058] The control sequence and adjustment range of the air register damper switch are set in the logic module. The general setting is as follows: when adjusting and opening the overfire air damper, each layer of the overfire air damper is opened by 2-5% in sequence from the upper layer to the lower layer. When the damper is opened to the limit value, the bias angle of each layer of the overfire air is adjusted and opened by 5 degrees each time in sequence from the upper layer to the lower layer until the maximum limit value. Each time a layer of the module is adjusted for the damper or the bias angle, a calculation and judgment are made until the adjustment requirements are met; when adjusting and closing the overfire air damper, each layer of the overfire air damper is closed by 2-5% in sequence from the upper layer to the lower layer. When the damper is closed to the limit value, the bias angle of each layer of the overfire air is adjusted and closed by 5 degrees each time in sequence from the upper layer to the lower layer until the minimum limit value. Each time a layer of the module is adjusted for the damper or the bias angle, a calculation and judgment are made until the adjustment requirements are met; when adjusting and opening the secondary air damper, each layer of the overfire air damper is opened by 1-2% in sequence from the upper layer to the lower layer. When adjusting and closing the secondary air damper, each layer of the overfire air damper is closed by 1-2% in sequence from the upper layer to the lower layer. Each time a layer of the module is adjusted, a calculation and judgment are made until the adjustment requirements for the oxygen content are met. Since the operation and adjustment characteristics of each boiler may vary greatly, the optimal damper switch combination sequence, adjustment range, upper and lower limits of automatic adjustment, and adjustment speed of a certain unit can be further determined through on-site tests and specifically set in the module, so as to carry out more effective and targeted adjustments, better conform to the specific characteristics of each unit, and be more personalized.

[0059] In some embodiments, the control sequence, adjustment range, upper and lower limits of automatic adjustment, and adjustment speed of the air register damper switch are set. The optimal scheme of a certain unit can be further determined through on-site tests and specifically set in the module, so as to carry out more effective and targeted adjustments, better conform to the specific characteristics of each unit, and meet personalized requirements.

[0060] The change adjustment of parameters such as the oxygen content is also coupled in the logic module to keep the change of the oxygen content within a certain allowable range during the adjustment. Generally, the change range can be set to 0.5-1%, which varies with the characteristics of each boiler. The optimal value can be specifically determined through on-site tests to avoid other impacts on combustion during the adjustment process, thereby affecting the stable operation of the unit.

[0061] The temperature measuring device measures the flue gas temperature in the flue and transmits the signal to the temperature adjustment control logic module in the DCS. This module performs deviation calculation and correction. After that, according to the calculation result, corresponding action instructions are issued to control the driving mechanism of the damper to coordinately control and adjust each damper. After a certain period of time, measurement and calculation are carried out again, and further adjustment, measurement, and calculation are performed according to the latest result, and further regulation is carried out. In this way, the flue gas temperature deviation is gradually reduced to the allowable range by means of negative feedback to achieve the purpose of automatic temperature adjustment.

[0062] The flue gas damper realizes the adjustment of its opening degree through a driving mechanism, and the driving mechanism can adopt a driving motor, compressed air or other existing driving methods to achieve this.

[0063] The damper and the matching driving mechanism are both original structures of the boiler.

[0064] The thermocouple or temperature sensor used to measure the flue gas temperature at the furnace outlet and other facilities are existing facilities of the boiler. The model can be specifically selected according to the actual situation and will not be elaborated here.

[0065] Embodiment 2:

[0066] This embodiment provides an automatic adjustment system for the temperature deviation of the flue gas at the furnace outlet of a boiler, including:

[0067] A data acquisition module, configured to: obtain the flue gas temperatures on both sides of the furnace outlet;

[0068] A temperature deviation calculation module, configured to: calculate the flue gas temperature deviation on both sides based on the obtained flue gas temperatures on both sides;

[0069] A first judgment module, configured to: judge whether the flue gas temperature deviation exceeds a preset limit. If so, adjust; otherwise, do not adjust;

[0070] A first adjustment module, configured to: if the flue gas temperature deviation exceeds the preset temperature deviation limit, adjust the opening degree of the burnout air damper and the bias angle of the burnout air according to the flue gas temperature deviation situation, in a preset order and amplitude; obtain the adjusted flue gas temperature deviation and flue gas oxygen content;

[0071] A second judgment module, configured to: judge whether the adjusted flue gas oxygen content deviation exceeds a preset limit. If so, continue to adjust; otherwise, stop adjusting;

[0072] A second adjustment module, configured to: when the adjusted flue gas oxygen content deviation exceeds the preset oxygen content limit, adjust the secondary air damper according to a preset ratio and amplitude until the oxygen content deviation is within the preset oxygen content limit;

[0073] A third judgment module, configured to: continue to obtain and compare whether the flue gas temperature deviation on both sides is reduced to within the preset temperature deviation limit. If so, stop adjusting; otherwise, continue to judge and adjust until the flue gas temperature deviation is reduced to within the preset temperature deviation limit.

[0074] The working method of the system is the same as that of the automatic adjustment method for the temperature deviation of the flue gas at the furnace outlet in Embodiment 1 and will not be elaborated here.

[0075] Embodiment 3:

[0076] This embodiment provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the steps of the automatic adjustment method for the flue gas temperature deviation at the boiler furnace outlet described in Embodiment 1 are implemented.

[0077] Embodiment 4:

[0078] This embodiment provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps of the automatic adjustment method for the flue gas temperature deviation at the boiler furnace outlet described in Embodiment 1 are implemented.

[0079] The foregoing are only the preferred embodiments of this embodiment and are not intended to limit this embodiment. For those skilled in the art, this embodiment can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this embodiment shall be included within the protection scope of this embodiment.

Claims

1. An automatic adjustment method for the flue gas temperature deviation at the furnace outlet of a boiler, characterized in that, it includes: Obtain the flue gas temperatures on both sides of the furnace outlet; Calculate the flue gas temperature deviation on both sides based on the obtained flue gas temperatures on both sides; Judge whether the flue gas temperature deviation exceeds the preset limit value. If so, perform adjustment; otherwise, do not adjust; If the flue gas temperature deviation exceeds the preset limit value of the temperature deviation, adjust the opening degree of the overfire air baffle and the offset angle of the overfire air according to the preset sequence and amplitude based on the situation of the flue gas temperature deviation, and obtain the adjusted flue gas temperature deviation and flue gas oxygen content; Continue to compare the oxygen content deviation in the flue gas before and after adjustment. If the oxygen content deviation exceeds the preset limit value of the oxygen content, adjust the secondary air baffle according to the preset ratio and amplitude until the oxygen content deviation is within the preset limit value of the oxygen content; When opening the secondary air baffle, within the preset opening increment range, open each layer of the secondary air baffle in sequence from the upper layer to the lower layer; When adjusting and closing the secondary air baffle, within the preset opening increment range, close each layer of the secondary air baffle in sequence from the upper layer to the lower layer; Calculate and judge once for each adjusted layer until the adjustment requirements of the oxygen content are met; Keep the change in the flue gas oxygen content during the adjustment within the preset allowable range; Judge whether the oxygen content in the flue gas before adjustment is greater than the oxygen content in the flue gas after adjustment. If so, open the secondary air baffle in layers according to the preset ratio and sequence; otherwise, close the secondary air according to the preset ratio and sequence; Continue to obtain and compare whether the flue gas temperature deviation on both sides is reduced to within the preset limit value of the temperature deviation. If so, stop the adjustment; otherwise, continue to judge and adjust until the flue gas temperature deviation is reduced to within the preset limit value of the temperature deviation.

2. The automatic adjustment method for the flue gas temperature deviation at the furnace outlet of a boiler according to claim 1, characterized in that, When opening the overfire air baffle, within the preset opening increment range, open it in sequence from the upper layer to the lower layer. When the overfire air baffle is opened to the limit value, adjust and open the offset angle of each layer of the overfire air in sequence from top to bottom with a preset amplitude each time. Calculate and judge once for each adjusted layer of the baffle or the offset angle until the adjustment requirements are met; When adjusting and closing the overfire air baffle, within the preset opening increment range, close each layer of the overfire air baffle in sequence from the upper layer to the lower layer. When the overfire air baffle is closed to the limit value, adjust and close the offset angle of each layer of the overfire air in sequence from top to bottom with a preset amplitude each time. Calculate and judge once for each adjusted layer of the baffle or the offset angle until the adjustment requirements are met.

3. The automatic adjustment method for the flue gas temperature deviation at the furnace outlet of a boiler according to claim 1, characterized in that, If the flue gas temperature on one side of the furnace outlet is greater than that on the other side, that is, the temperature distribution from high to low is clockwise, then it is judged whether the opening degree of the burnout air damper is greater than the first preset limit opening degree. If so, the reverse-cut burnout air is closed by a preset ratio; otherwise, an alarm is given. If the flue gas temperature on one side of the furnace outlet is less than that on the other side, that is, the temperature distribution from high to low is counterclockwise, then it is judged whether the opening degree of the burnout air damper is greater than the second preset limit opening degree. If so, an alarm is given; otherwise, the reverse-cut burnout air is opened by a preset ratio.

4. A method for automatically adjusting the flue gas temperature deviation at the boiler furnace outlet according to claim 1, characterized in that, the adjustment sequence, adjustment amplitude, adjustment size limit and adjustment speed of the burnout air damper and the secondary air damper are adjustable.

5. An automatic adjustment system for the flue gas temperature deviation at the boiler furnace outlet, characterized in that, comprising: a data acquisition module configured to: obtain the flue gas temperatures on both sides of the furnace outlet; a temperature deviation calculation module configured to: calculate the flue gas temperature deviation on both sides based on the obtained flue gas temperatures on both sides; a first judgment module configured to: judge whether the flue gas temperature deviation exceeds a preset limit. If so, adjustment is performed; otherwise, no adjustment is made; a first adjustment module configured to: if the flue gas temperature deviation exceeds the preset temperature deviation limit, adjust the opening degree of the burnout air damper and the offset angle of the burnout air according to the flue gas temperature deviation situation in a preset sequence and amplitude; obtain the adjusted flue gas temperature deviation and flue gas oxygen content; a second judgment module configured to: judge whether the adjusted flue gas oxygen content deviation exceeds a preset limit. If so, continue to adjust; otherwise, stop adjusting; a second adjustment module configured to: when the adjusted flue gas oxygen content deviation exceeds the preset oxygen content limit, adjust the secondary air damper according to a preset ratio and amplitude until the oxygen content deviation is within the preset oxygen content limit; when opening the secondary air damper, within the preset opening increment range, open each layer of the secondary air damper in sequence from the upper layer to the lower layer; when closing the secondary air damper, within the preset opening increment range, close each layer of the secondary air damper in sequence from the upper layer to the lower layer; calculate and judge once for each adjusted layer until the adjustment requirement of the oxygen content is met; keep the change of the flue gas oxygen content within the preset allowable range during the adjustment; judge whether the oxygen content in the flue gas before adjustment is greater than the oxygen content in the flue gas after adjustment. If so, open each layer of the secondary air damper in a preset ratio and sequence; otherwise, close the secondary air in a preset ratio and sequence; a third judgment module configured to: continue to obtain and compare whether the flue gas temperature deviation on both sides is reduced to within the preset temperature deviation limit. If so, stop adjusting; otherwise, continue to judge and adjust until the flue gas temperature deviation is reduced to within the preset temperature deviation limit.

6. A computer-readable storage medium, on which a computer program is stored, characterized in that, when the program is executed by a processor, the steps of the method for automatically adjusting the flue gas temperature deviation at the boiler furnace outlet according to any one of claims 1-4 are implemented.

7. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, when the processor executes the program, the steps of the automatic adjustment method for the flue gas temperature deviation at the boiler furnace outlet according to any one of claims 1-4 are implemented.

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