Device and method for adjusting over fire air of boiler

Abstract

The embodiment of the invention provides a boiler over-fire air adjusting device and method, and the device comprises an over-fire air bellow which is arranged at an inlet of a flue in a hearth of a combustion boiler, and an even number of over-fire air nozzles, partition plates and flow adjusting parts which are arranged at air inlets of the over-fire air nozzles are arranged in the over-fire air bellow; the carbon monoxide concentration detection equipment is arranged at an outlet of the flue in the hearth; the heat exchanger is arranged upwards along the flow direction of the flue gas in the hearth and is arranged between the inlet and the outlet of the flue; the temperature detection equipment is arranged on the outer wall of the heat exchanger; the control device is electrically connected with the carbon monoxide concentration detection equipment, the temperature detection equipment and the flow adjusting part and is used for controlling the flow adjusting part according to the comparison between the actual carbon monoxide concentration value detected by the carbon monoxide concentration detection equipment and the preset carbon monoxide concentration value; or the control device controls the flow adjusting piece to adjust the air supply amount of the over fire air nozzle according to the comparison between the actual wall temperature value detected by the temperature detection equipment and the preset wall temperature value.

Description

Technical Field

[0001] The embodiments of the present disclosure belong to the technical field of thermal power unit equipment, and specifically relate to a boiler burnout air adjustment device and method. Background Art

[0002] As the energy conservation and carbon reduction work of thermal power units is further promoted, the requirements for the operating parameters of coal-fired boilers are becoming increasingly stringent. In order to reduce the coal consumption of the unit, it is usually necessary for the boiler to operate with oxygen content and steam temperature that reach or even exceed the design value. Under such strict operating conditions, it is very important to fine-tune the optimization and adjustment of the boiler, and the burnout air is one of the key means of boiler combustion adjustment.

[0003] At present, a large number of scholars and practitioners at home and abroad have conducted research on overburnt air adjustment and found that the overburnt air adjustment of hedge combustion boilers has a significant impact on key parameters such as boiler combustion deviation, wall temperature, and CO concentration. In the combustion adjustment test, reasonable adjustment of the overburnt air is beneficial to improve combustion uniformity, reduce local wall temperature high points and CO high points, and improve boiler operation safety and economy.

[0004] However, currently, the adjustment of the overburnt air, especially the adjustment of the overburnt air lever, can only be done manually, and it is fixed in a certain position according to the test conclusion and remains unchanged in daily operation. In fact, the combustion state of the boiler varies greatly under different loads, different grinding combinations, different coal qualities, etc. The current manual overburnt air adjustment mode is difficult to adapt to the flexible operation mode of thermal power units. When the combustion conditions change, the overburnt air cannot change accordingly, which leads to problems such as overheating of the boiler and reduced combustion efficiency. Summary of the invention

[0005] The embodiments of the present disclosure aim to solve at least one of the technical problems existing in the prior art and provide a boiler burnout air regulating device and method.

[0006] According to a first aspect of an embodiment of the present disclosure, there is provided a boiler overburnt air regulating device, comprising:

[0007] A burnout wind box is arranged at the entrance of the flue in the furnace of the combustion boiler, wherein an even number of burnout air nozzles, a baffle, and a flow regulating member arranged at the air inlet of the burnout air nozzle are arranged in the burnout wind box, wherein the flow regulating member is used to adjust the air supply volume of the burnout air nozzle; the baffle is arranged at the symmetric center of the even number of the burnout air nozzles to define a first side and a second side in the burnout wind box, and the first side and the second side of the burnout wind box are correspondingly provided with an air inlet flow regulating member;

[0008] A plurality of carbon monoxide concentration detection devices are arranged at the outlet of the flue in the furnace, and the plurality of carbon monoxide concentration detection devices are arranged one-to-one correspondingly to an even number of the overburnt air nozzles, for detecting the carbon monoxide concentration in the flue gas;

[0009] The heat exchanger is arranged along the flow direction of the flue gas in the furnace and is set between the inlet and outlet of the flue to absorb the heat in the flue gas;

[0010] A plurality of temperature detection devices are arranged on the outer wall of the heat exchanger, and the plurality of temperature detection devices are arranged one-to-one correspondingly to an even number of the overburnt air nozzles, and are used to detect the wall temperature of the heat exchanger; wherein a plurality of overburnt air areas are divided in the width direction of the furnace, each overburnt air area includes an overburnt air nozzle, and at least one temperature detection device and one carbon monoxide concentration detection device are sequentially arranged along the flow direction of the overburnt air sprayed from the overburnt air nozzle;

[0011] A control device is electrically connected to the carbon monoxide concentration detection device, the temperature detection device and the flow regulating member, respectively. The control device controls the flow regulating member to adjust the air supply of the burnout air nozzle according to a comparison between an actual value of the carbon monoxide concentration detected by the carbon monoxide concentration detection device and a preset value of the carbon monoxide concentration; or the control device controls the flow regulating member to adjust the air supply of the burnout air nozzle according to a comparison between an actual value of the wall temperature detected by the temperature detection device and a preset value of the wall temperature.

[0012] A second aspect of an embodiment of the present disclosure provides a boiler overburnt air regulating method, the regulating method being implemented according to the boiler overburnt air regulating device described above, comprising:

[0013] Detect the actual value of carbon monoxide concentration in the flue gas of each overburnt air area in the boiler flue;

[0014] Detecting the actual value of the wall temperature of the heat exchanger in each overburnt air area in the boiler flue;

[0015] According to the comparison result of the actual wall temperature detected by the temperature detection device and the preset wall temperature value, or according to the comparison result of the actual carbon monoxide concentration detected by the carbon monoxide concentration detection device and the preset carbon monoxide concentration value, the flow adjustment component is controlled to adjust the air supply volume of the burnout air nozzle.

[0016] Optionally, according to a comparison result that an actual wall temperature detected by the temperature detection device is higher than a preset wall temperature value, the opening of the flow regulating member is increased to increase the air supply volume of the overburnt air nozzle.

[0017] Optionally, the partition divides the burnout wind box into a first side and a second side which are separated from each other; wherein, it further comprises:

[0018] Detecting an actual value of the wall temperature of the heat exchanger in the overburnt air region on the first side or the second side after the opening of the flow regulating member is increased;

[0019] According to the comparison result that the actual wall temperature detected by the temperature detection device is higher than the preset wall temperature value, the opening of the flow regulating member in the burnout air area other than the burnout air area on the first side or the second side is reduced.

[0020] Optionally, also include:

[0021] Detecting an actual value of the wall temperature of the heat exchanger in the overburnt air region on the first side or the second side after reducing the opening of the flow regulating member in the overburnt air region other than the overburnt air region on the first side or the second side;

[0022] According to the comparison result that the actual wall temperature detected by the temperature detection device is higher than the preset wall temperature value, the opening of the burnout wind box air inlet flow regulating member on the second side or the first side is reduced, or the opening of the burnout wind box air inlet flow regulating member on the first side or the second side is increased.

[0023] Optionally, according to a comparison result that an actual value of carbon monoxide concentration detected by the carbon monoxide detection device is higher than a preset value of carbon monoxide concentration, the opening of the flow regulating member is increased to increase the air supply volume of the overburnt air nozzle.

[0024] Furthermore, the partition divides the burnout wind box into a first side and a second side which are separated from each other; wherein, it also includes:

[0025] Detecting an actual value of the carbon monoxide concentration in the flue gas in the overburnt air area on the first side or the second side after the opening of the flow regulating member is increased;

[0026] According to the comparison result that the actual value of the carbon monoxide concentration detected by the carbon monoxide concentration detection device is higher than the preset value of the carbon monoxide concentration, the opening of the flow regulating member in the burnout air area other than the burnout air area on the first side or the second side is reduced.

[0027] Furthermore, it also includes:

[0028] Detecting the actual value of the carbon monoxide concentration in the flue gas in the overburnt air area on the first side or the second side after reducing the opening of the flow regulating member in the overburnt air area other than the overburnt air area on the first side or the second side;

[0029] According to the comparison result that the actual value of the carbon monoxide concentration detected by the carbon monoxide concentration detection equipment is higher than the preset value of the carbon monoxide concentration, the opening of the burnout bellows air inlet flow regulating member on the second side or the first side is reduced, or the opening of the burnout bellows air inlet flow regulating member on the first side or the second side is increased.

[0030] Furthermore, it also includes: detecting the actual value of the wall temperature of the heat exchanger in the burnout air area; and adjusting the opening of the flow regulating component according to the actual value of the wall temperature, based on the comparison result that the actual value of the wall temperature detected by the temperature detection device is higher than the preset value of the wall temperature.

[0031] The beneficial effects of the embodiments of the present disclosure include:

[0032] In the present disclosure, by detecting the carbon monoxide concentration in the flue gas and automatically adjusting the supply volume of the burnout air according to the comparison between the actual value of the carbon monoxide concentration and the preset value, the incompletely burned fuel can be effectively reduced and the combustion efficiency can be improved. By detecting the wall temperature of the heat exchanger and automatically adjusting the supply volume of the burnout air according to the comparison between the actual value of the wall temperature and the preset value, local overheating and pipe explosion can be prevented, thereby improving the safety of the heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a structural schematic diagram of a boiler overburnt air regulating device according to an embodiment of the present disclosure;

[0034] Figure 2 The present invention is a flow chart of a boiler overburnt air regulation method according to another embodiment of the present invention.

[0035] In the figure, 1. burnout air nozzle; 2. heat exchanger; 3. economizer outlet; 4. partition; 5. furnace; 6. burnout wind box; 21. screen superheater; 22. high-temperature superheater; 23. high-temperature reheater. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the technical solution of the present disclosure, the present disclosure is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0037] The following is a further detailed description of the implementation methods of the present application in conjunction with the accompanying drawings and examples. The detailed descriptions and drawings of the following examples are used to illustrate the principles of the present application, but cannot be used to limit the scope of the present application, that is, the present application is not limited to the described embodiments. In the description of the present application, it should be noted that, unless otherwise specified, the meaning of "multiple" is more than two; the orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "inside", "outside", etc. is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. "Vertical" is not vertical in the strict sense, but within the error tolerance range. "Parallel" is not parallel in the strict sense, but within the error tolerance range.

[0038] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0039] like Figure 1 As shown, a boiler burnout wind regulating device and method, a burnout wind box is arranged at the entrance of the flue in the furnace 5 of the combustion boiler, and an even number of burnout air nozzles 1, a partition 4, and a flow regulating member arranged at the air inlet of the burnout air nozzle are arranged in the burnout wind box 6, and the flow regulating member is used to adjust the air supply volume of the burnout air nozzle. The partition 4 is arranged at the symmetric center of the even number of burnout air nozzles to define a first side and a second side in the burnout wind box 6, and the first side and the second side of the burnout wind box are correspondingly provided with an air inlet flow regulating member, and the air inlet flow regulating member is used to adjust the air flow of the inlet air in the first side and the second side of the burnout wind box.

[0040] Multiple carbon monoxide concentration detection devices are arranged at the outlet of the flue in the furnace 5 ( Figure 1 At the economizer outlet 3), a plurality of carbon monoxide concentration detection devices are arranged in one-to-one correspondence with an even number of overburnt air nozzles, for detecting the carbon monoxide concentration in the flue gas. The heat exchanger is arranged along the flow direction of the flue gas in the furnace, and is arranged between the inlet and outlet of the flue, for absorbing the heat in the flue gas. A plurality of temperature detection devices are arranged on the outer wall of the heat exchanger 2, and a plurality of the temperature detection devices are arranged in one-to-one correspondence with an even number of the overburnt air nozzles, for detecting the wall temperature of the heat exchanger. Among them, a plurality of overburnt air areas are divided in the width direction of the furnace, each overburnt air area includes an overburnt air nozzle, and at least one temperature detection device and a carbon monoxide concentration detection device are arranged in sequence along the flow direction of the overburnt air sprayed from the overburnt air nozzle.

[0041] The control device is electrically connected to the carbon monoxide concentration detection device, the temperature detection device and the flow adjustment member respectively, and the control device controls the flow adjustment member to adjust the air supply volume of the burnout air nozzle according to the comparison between the actual value of the carbon monoxide concentration detected by the carbon monoxide concentration detection device and the preset value of the carbon monoxide concentration. Or the control device controls the flow adjustment member to adjust the air supply volume of the burnout air nozzle according to the comparison between the actual value of the wall temperature detected by the temperature detection device and the preset value of the wall temperature.

[0042] In the present disclosure, by detecting the carbon monoxide concentration in the flue gas and automatically adjusting the supply volume of the overburnt air according to the comparison between the actual value of the carbon monoxide concentration and the preset value, the incompletely burned fuel can be effectively reduced and the combustion efficiency can be improved. By detecting the wall temperature of the heat exchanger and automatically adjusting the supply volume of the overburnt air according to the comparison between the actual value of the wall temperature and the preset value, local overheating and pipe burst can be prevented and the safety of the heat exchanger can be improved. In some embodiments, the heat exchanger includes a screen superheater 21, a high-temperature superheater 22 and a high-temperature reheater 23 arranged in sequence along the flow direction of the flue gas in the furnace.

[0043] In some embodiments, the carbon monoxide concentration detection device is a CO online measuring instrument.

[0044] In some embodiments, the flow regulating member is a burnout air volume regulating rod.

[0045] In some embodiments, there are multiple overburnt air nozzles, and the multiple overburnt air nozzles are arranged at intervals along the width direction of the furnace. There are multiple flow regulating members, and the multiple flow regulating members are arranged one-to-one corresponding to the multiple overburnt air nozzles. There are multiple carbon monoxide concentration detection devices and multiple temperature detection devices.

[0046] Among them, multiple burnout air areas are arranged in the width direction of the furnace, and each burnout air area includes a burnout air nozzle, and a temperature detection device and a carbon monoxide concentration detection device are sequentially arranged along the burnout air flow direction sprayed from the burnout air nozzle.

[0047] In the present disclosure, multiple overburnt air zones are arranged in the width direction of the furnace, and each zone is equipped with an independent overburnt air nozzle, flow adjustment member, temperature detection device and carbon monoxide concentration detection device, so that fine control of each zone can be achieved. Each overburnt air zone can be independently adjusted according to its own temperature and carbon monoxide concentration, avoiding the imbalance problem caused by global adjustment and improving the uniformity and efficiency of overall combustion.

[0048] Furthermore, through multi-point detection and local adjustment, the combustion conditions of each area can be controlled more accurately, reducing incompletely burned fuel and improving combustion efficiency. And the flow adjustment parts of each area can be dynamically adjusted according to real-time detection data to ensure that the combustion conditions of each area are always in the best state.

[0049] Specifically, there are an even number of burnout air nozzles, and the even number of burnout air nozzles are arranged at intervals along the width direction of the furnace. There are multiple flow regulating members, and the multiple flow regulating members are arranged one-to-one correspondingly to the multiple burnout air nozzles. There are multiple carbon monoxide concentration detection devices and multiple temperature detection devices. A partition is also arranged in the burnout wind box, and the partition is arranged at the symmetrical center of the even number of burnout air nozzles.

[0050] Among them, multiple burnout air areas are arranged in the width direction of the furnace, each burnout air area includes a burnout air nozzle, and along the burnout air flow direction sprayed from the burnout air nozzle, at least one temperature detection device and a carbon monoxide concentration detection device are sequentially arranged.

[0051] In the present disclosure, by arranging multiple overburnt air zones in the width direction of the furnace, each zone is equipped with an independent overburnt air nozzle, flow adjustment member, temperature detection device and carbon monoxide concentration detection device, so that fine control of each zone can be achieved and combustion efficiency can be improved. Each overburnt air zone can be independently adjusted according to its own temperature and carbon monoxide concentration, avoiding the imbalance problem caused by global adjustment, and ensuring that the combustion conditions of each zone are always in the best state.

[0052] Furthermore, the airflow enters the burnout air nozzle from the burnout air box. For an even number of burnout air nozzles, a partition can be set in the middle of the wind box, so that the overall burnout air intake volume on the left / right side can be changed by adjusting the opening of the burnout air layer damper.

[0053] like Figure 2 As shown, a second aspect of the embodiment of the present disclosure provides a boiler overburnt air regulating method, the regulating method is implemented according to the above-mentioned boiler overburnt air regulating device, and includes:

[0054] S101. Detect the actual value of the carbon monoxide concentration in the flue gas of each overburnt air area in the boiler flue.

[0055] S102. Detect the actual value of the wall temperature of each over-combustion air area heat exchanger in the boiler flue.

[0056] S103, controlling the flow regulating component to regulate the air supply of the burnout air nozzle according to the comparison result of the actual wall temperature detected by the temperature detecting device with the preset wall temperature value, or according to the comparison result of the actual carbon monoxide concentration detected by the carbon monoxide concentration detecting device with the preset carbon monoxide concentration value.

[0057] In the present disclosure, by detecting the carbon monoxide concentration in the flue gas of each overburnt air zone and the wall temperature of the heat exchanger, and making local adjustments based on the detection results, it is possible to achieve refined control of each zone and improve combustion efficiency. Each overburnt air zone can be independently adjusted according to its own temperature and carbon monoxide concentration, avoiding the imbalance problem caused by global adjustment and ensuring that the combustion conditions of each zone are always in the best state.

[0058] The wall temperature of each area can be monitored in real time by independent temperature detection equipment, and the air supply volume of the burnout air can be adjusted in time to prevent equipment damage caused by local overheating.

[0059] In some embodiments, according to the comparison result that the actual wall temperature detected by the temperature detection device is higher than the preset wall temperature value, the opening of the flow regulating member is increased to increase the air supply volume of the burnout air nozzle.

[0060] In the present disclosure, by real-time monitoring of the wall temperature and quickly increasing the opening of the flow regulating member according to the comparison result of the actual wall temperature value and the preset value, the temperature change can be quickly responded to to ensure that the combustion process is always in the best state. By increasing the air supply volume of the burnout air, the wall temperature can be effectively reduced to ensure the safety of the equipment, and the complete combustion of the fuel can be promoted, the combustion efficiency can be improved, and the incompletely burned fuel can be reduced.

[0061] In some embodiments, the baffle divides the burnout wind box into a first side and a second side separated from each other; wherein the baffle further comprises:

[0062] After the opening of the flow regulating element is increased, the actual value of the wall temperature of the heat exchanger in the overburnt air area on the first side or the second side is detected.

[0063] According to the comparison result that the actual wall temperature detected by the temperature detection device is higher than the preset wall temperature value, the opening of the flow regulating member in the burnout air area other than the burnout air area on the first side or the second side is reduced.

[0064] In the present disclosure, by reducing the opening of the flow regulating member in the overburnt air area other than the overburnt air area on the first side or the second side, the relative air intake in the overburnt air area can be increased, thereby effectively cooling the heat exchanger in the overburnt air area.

[0065] In some embodiments, it also includes:

[0066] After reducing the opening of the flow regulating member in the overburnt air area except the overburnt air area in the first side or the second side, the actual value of the wall temperature of the heat exchanger in the overburnt air area in the first side or the second side is detected.

[0067] According to the comparison result that the actual wall temperature detected by the temperature detection device is higher than the preset wall temperature value, the opening of the burnout wind box air inlet flow regulating member on the second side or the first side is reduced, or the opening of the burnout wind box air inlet flow regulating member on the first side or the second side is increased.

[0068] In the present disclosure, by reducing the opening of the burnout wind box air inlet flow rate regulating member on the second side or the first side, or increasing the opening of the burnout wind box air inlet flow rate regulating member on the first side or the second side, the relative air intake volume in all burnout wind areas on the first side or the second side can be increased, thereby effectively cooling the heat exchanger in the burnout wind area.

[0069] In some embodiments, according to the comparison result that the actual value of the carbon monoxide concentration detected by the carbon monoxide detection device is higher than the preset value of the carbon monoxide concentration, the opening of the flow regulating member is increased to increase the air supply volume of the burnout air nozzle.

[0070] In the present disclosure, by real-time monitoring of the carbon monoxide concentration and rapidly increasing the opening of the flow regulating member according to the comparison result between the actual value and the preset value, it is possible to quickly respond to the situation of insufficient combustion and ensure that the combustion process is always in the best state. By increasing the air supply volume of the burnout air, it is possible to promote the complete combustion of the fuel, reduce the incompletely burned fuel, and improve the combustion efficiency.

[0071] In some embodiments, the baffle divides the burnout wind box into a first side and a second side separated from each other; wherein the baffle further comprises:

[0072] After the opening of the flow regulating member is increased, the actual value of the carbon monoxide concentration in the flue gas in the overburnt air area on the first side or the second side is detected.

[0073] According to the comparison result that the actual value of the carbon monoxide concentration detected by the carbon monoxide concentration detection device is higher than the preset value of the carbon monoxide concentration, the opening of the flow regulating member of the burnout air area other than the burnout air area on the first side or the second side is reduced.

[0074] In the present disclosure, by reducing the opening of the flow regulating member of the overburnt air area other than the overburnt air area on the first side or the second side, the relative air intake in the overburnt air area can be increased, the complete combustion of the fuel can be promoted, the incompletely burned fuel can be reduced, and the combustion efficiency can be improved. That is, by detecting the carbon monoxide concentration in a certain overburnt air area after increasing the opening of the flow regulating member in the area, it can be ensured that the combustion conditions in the area are optimized and the combustion efficiency is improved. By reducing the opening of the flow regulating member in other overburnt air areas, the relative air intake in the overburnt air area can be increased, the temperature of the flue gas can be effectively reduced, thereby reducing the wall temperature and ensuring the safety of the equipment.

[0075] In some embodiments, it also includes:

[0076] After detecting and reducing the opening of the flow regulating member in the overburnt air area other than the overburnt air area in the first side or the second side, the actual value of the carbon monoxide concentration in the flue gas in the overburnt air area in the first side or the second side is obtained.

[0077] According to the comparison result that the actual value of the carbon monoxide concentration detected by the carbon monoxide concentration detection equipment is higher than the preset value of the carbon monoxide concentration, the opening of the burnout bellows inlet flow regulating member on the second side or the first side is reduced, or the opening of the burnout bellows inlet flow regulating member on the first side or the second side is increased.

[0078] In the present disclosure, by reducing the opening of the burnout wind box air inlet flow rate regulating member on the second side or the first side, or increasing the opening of the burnout wind box air inlet flow rate regulating member on the first side or the second side, the relative air intake volume in all burnout wind areas on the first side or the second side can be increased, thereby promoting the complete combustion of the fuel in the burnout wind area, reducing the incompletely burned fuel, and improving the combustion efficiency. Furthermore, by increasing the air supply volume of the burnout wind, the carbon monoxide concentration in the flue gas can be effectively reduced, the emission of harmful gases can be reduced, and the environmental protection performance can be improved. The reduction in carbon monoxide concentration means that the combustion is more complete, the products of incomplete combustion are reduced, and the generation of other harmful substances is further reduced.

[0079] In the present disclosure, by adjusting the opening of a flow regulating member in a certain overburned air region and detecting the carbon monoxide concentration in the region, it is possible to ensure that the combustion conditions in the region are optimized and the combustion efficiency is improved. By adjusting the opening of the flow regulating member in other overburned air regions, the relative air intake volume of the overburned air region can be increased, thereby ensuring sufficient combustion in the overburned air region and reducing the generation of incomplete combustion products and other harmful substances.

[0080] In some embodiments, it also includes: detecting the actual value of the wall temperature of the heat exchanger in the burnout air area; and adjusting the opening of the flow regulating component according to the actual value of the wall temperature based on the comparison result that the actual value of the wall temperature detected by the temperature detection device is higher than the preset value of the wall temperature.

[0081] In the present disclosure, equipment safety priority is higher than environmental priority, that is, the wall temperature regulation mode is higher than the carbon monoxide regulation mode.

[0082] A specific example provided by the present disclosure includes:

[0083] like Figure 1 As shown, Figure 1 In order to offset the combustion of boiler flue gas from the overburnt air nozzle to the economizer outlet, 1 to N overburnt air areas are arranged from side A to side B in the furnace width direction. Each overburnt air area corresponds to an overburnt air nozzle and an economizer outlet. A series of heat exchangers (including screen superheaters, high-temperature superheaters and high-temperature reheaters) are located downstream of the overburnt air nozzles, and the flue at the furnace outlet is divided into two flues, side A and side B, after passing through the economizer.

[0084] In the disclosed scheme, in order to accurately grasp the CO concentration generated by coal powder combustion, a CO online measuring instrument is set at the location of the economizer outlet flue, as shown in the attached Figure 1 As shown, the number of CO online measuring instruments is the same as the number N of single-layer overburnt air outlets, and their arrangement positions in the flue width direction correspond one to one with the positions of the overburnt air in the furnace width direction.

[0085] According to the arrangement positions of the overburnt air nozzles, the screen superheater, high temperature superheater and high temperature reheater are divided into N overburnt air areas in the width direction with the center lines of adjacent overburnt air nozzles as dividing lines.

[0086] The regulating device disclosed in the present invention includes a wall temperature priority regulating mode: the maximum allowable temperature of the platen superheater, high temperature superheater and high temperature reheater tube wall is recorded as Tmax. When the tube wall temperature (actual value of the wall temperature) of the platen superheater, high temperature superheater and high temperature reheater in the overburning air area Ni exceeds Tmax (preset value of the wall temperature), for the safety of unit operation, the regulating device will give priority to regulating the wall temperature. The adjustment method is as follows:

[0087] 1) Based on the control of the control device, the burnout air volume regulating lever in the Ni burnout air zone is opened, and if the wall temperature drops below Tmax, the regulation is stopped; 2) If the wall temperature is still higher than Tmax after the burnout air volume regulating lever is opened to 100% in the Ni burnout air zone, then based on the control of the control device, the burnout air volume regulating levers in the burnout air zones on the same side except the Ni burnout air zone are closed. Specifically, when Ni≤N / 2, the burnout air volume regulating levers [1, Ni) and (Ni, N / 2] are closed; when Ni>N / 2, the burnout air volume regulating levers (N / 2, Ni) and (Ni, N] are closed until the wall temperature drops below Tmax, and the lower limit of the adjustment is 30%; 3) if the wall temperature is still too high after adjustment in step b, the burnout wind box air inlet flow regulating member on the side where the Ni burnout wind area is located is opened, or the burnout wind box air inlet flow regulating member on the other side is closed, until the wall temperature drops below Tmax, and the opening adjustment range is 20% to 100%.

[0088] CO priority regulation mode: When the tube wall temperature (actual wall temperature value) of the screen superheater, high temperature superheater and high temperature reheater in the overburnt air area Ni does not exceed Tmax (preset wall temperature value), the regulating device will give priority to regulating the CO concentration at the economizer outlet to improve the thermal efficiency of boiler combustion. According to the CO instrument data at the economizer outlet, the high CO concentration area is determined. Assuming that the CO concentration in the overburnt air area Ni is the highest, the regulation method is similar to the wall temperature condition method, as follows:

[0089] 1) Based on the control of the control device, the burnout air volume adjustment lever in the burnout air area Ni is opened. If the CO concentration (actual value of carbon monoxide concentration) drops to a value lower than the carbon monoxide concentration value (preset value of carbon monoxide concentration) of other burnout air areas, the adjustment is stopped; 2) If, based on the control of the control device, the CO concentration is still higher than that of other areas after the burnout air volume adjustment lever in the burnout air area Ni is opened to 100%, based on the control of the control device, the burnout air volume adjustment levers corresponding to the burnout air areas on the same side except the burnout air area Ni are closed. Specifically, when Ni≤N / 2, the burnout wind volume regulating levers of the burnout wind areas [1, Ni) and (Ni, N / 2] are closed; when Ni>N / 2, the burnout wind volume regulating levers of the burnout wind areas (N / 2, Ni) and (Ni, N] are closed until the CO concentration is lower than that of other areas, and the lower limit of adjustment is 30%; 3) If the CO concentration is still high after adjustment in step b, then based on the control of the control device, the opening of the burnout wind box inlet flow regulating member on the side where Ni is located is increased, or the opening of the burnout wind box inlet flow regulating member on the other side is closed, until the CO concentration is lower than that of other areas, and the opening adjustment range is 20% to 100%.

[0090] 3) During the CO concentration adjustment process, when the wall temperature exceeds Tmax, return to the wall temperature priority adjustment mode.

[0091] According to a third aspect of the embodiments of the present disclosure, a computer-readable storage medium is provided, on which a computer program is stored.

[0092] When the computer program is executed by a processor, the above-mentioned boiler overfire air adjustment method can be implemented.

[0093] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present disclosure, but the present disclosure is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and substance of the present disclosure, and these modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A boiler burnout air regulating device, characterized in that: include: A burnout wind box is arranged at the entrance of the flue in the furnace of the combustion boiler, wherein an even number of burnout air nozzles, a baffle, and a flow regulating member arranged at the air inlet of the burnout air nozzle are arranged in the burnout wind box, wherein the flow regulating member is used to adjust the air supply volume of the burnout air nozzle; the baffle is arranged at the symmetric center of the even number of the burnout air nozzles to define a first side and a second side in the burnout wind box, and the first side and the second side of the burnout wind box are correspondingly provided with an air inlet flow regulating member; A plurality of carbon monoxide concentration detection devices are arranged at the outlet of the flue in the furnace, and the plurality of carbon monoxide concentration detection devices are arranged one-to-one correspondingly to an even number of the overburnt air nozzles, for detecting the carbon monoxide concentration in the flue gas; The heat exchanger is arranged along the flow direction of the flue gas in the furnace and is set between the inlet and outlet of the flue to absorb the heat in the flue gas; A plurality of temperature detection devices are arranged on the outer wall of the heat exchanger, and the plurality of temperature detection devices are arranged one-to-one correspondingly to an even number of the overburnt air nozzles, and are used to detect the wall temperature of the heat exchanger; wherein a plurality of overburnt air areas are divided in the width direction of the furnace, each overburnt air area includes an overburnt air nozzle, and at least one temperature detection device and one carbon monoxide concentration detection device are sequentially arranged along the flow direction of the overburnt air sprayed from the overburnt air nozzle; A control device is electrically connected to the carbon monoxide concentration detection device, the temperature detection device and the flow regulating member, respectively. The control device controls the flow regulating member to adjust the air supply of the burnout air nozzle according to a comparison between an actual value of the carbon monoxide concentration detected by the carbon monoxide concentration detection device and a preset value of the carbon monoxide concentration; or the control device controls the flow regulating member to adjust the air supply of the burnout air nozzle according to a comparison between an actual value of the wall temperature detected by the temperature detection device and a preset value of the wall temperature.

2. A boiler overburnt air adjustment method, the adjustment method is implemented according to the overburnt air automatic adjustment device of the hedge combustion boiler according to claim 1, characterized in that: include: Detect the actual value of carbon monoxide concentration in the flue gas of each overburnt air area in the boiler flue; Detecting the actual value of the wall temperature of the heat exchanger in each overburnt air area in the boiler flue; According to the comparison result of the actual wall temperature detected by the temperature detection device and the preset wall temperature value, or according to the comparison result of the actual carbon monoxide concentration detected by the carbon monoxide concentration detection device and the preset carbon monoxide concentration value, the flow adjustment component is controlled to adjust the air supply volume of the burnout air nozzle.

3. A boiler overburnt air adjustment method according to claim 2, characterized in that: According to the comparison result that the actual wall temperature detected by the temperature detection device is higher than the preset wall temperature value, the opening of the flow regulating member is increased to increase the air supply volume of the overburnt air nozzle.

4. A boiler overburnt air adjustment method according to claim 3, characterized in that: The partition divides the burnout wind box into a first side and a second side which are separated from each other; wherein, it also includes: Detecting an actual value of the wall temperature of the heat exchanger in the overburnt air region on the first side or the second side after the opening of the flow regulating member is increased; According to the comparison result that the actual wall temperature detected by the temperature detection device is higher than the preset wall temperature value, the opening of the flow regulating member in the burnout air area other than the burnout air area on the first side or the second side is reduced.

5. A boiler overburnt air adjustment method according to claim 4, characterized in that: Also includes: Detecting an actual value of the wall temperature of the heat exchanger in the overburnt air region on the first side or the second side after reducing the opening of the flow regulating member in the overburnt air region other than the overburnt air region on the first side or the second side; According to the comparison result that the actual wall temperature detected by the temperature detection device is higher than the preset wall temperature value, the opening of the burnout wind box air inlet flow regulating member on the second side or the first side is reduced, or the opening of the burnout wind box air inlet flow regulating member on the first side or the second side is increased.

6. A boiler overburnt air adjustment method according to claim 2, characterized in that: According to the comparison result that the actual value of the carbon monoxide concentration detected by the carbon monoxide detection device is higher than the preset value of the carbon monoxide concentration, the opening of the flow regulating member is increased to increase the air supply volume of the burnout air nozzle.

7. A boiler overburnt air adjustment method according to claim 6, characterized in that: The partition divides the burnout wind box into a first side and a second side which are separated from each other; wherein, it also includes: Detecting an actual value of the carbon monoxide concentration in the flue gas in the overburnt air area on the first side or the second side after the opening of the flow regulating member is increased; According to the comparison result that the actual value of the carbon monoxide concentration detected by the carbon monoxide concentration detection device is higher than the preset value of the carbon monoxide concentration, the opening of the flow regulating member in the burnout air area other than the burnout air area on the first side or the second side is reduced.

8. A boiler overburnt air adjustment method according to claim 7, characterized in that: Also includes: Detecting the actual value of the carbon monoxide concentration in the flue gas in the overburnt air area on the first side or the second side after reducing the opening of the flow regulating member in the overburnt air area other than the overburnt air area on the first side or the second side; According to the comparison result that the actual value of the carbon monoxide concentration detected by the carbon monoxide concentration detection equipment is higher than the preset value of the carbon monoxide concentration, the opening of the burnout bellows air inlet flow regulating member on the second side or the first side is reduced, or the opening of the burnout bellows air inlet flow regulating member on the first side or the second side is increased.

9. A boiler overburnt air adjustment method according to claim 7, characterized in that: Also includes: Detecting the actual value of the wall temperature of the heat exchanger in the overburnt air area; According to the comparison result that the actual value of the wall temperature detected by the temperature detection device is higher than the preset value of the wall temperature, the opening of the flow regulating member is preferentially adjusted according to the actual value of the wall temperature.

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