Asymmetric characteristic dynamic control method for waste incineration power generation boiler and flue gas pipe network thereof

Abstract

The application relates to a garbage incineration power generation boiler and a non-symmetrical characteristic dynamic control method of a flue gas pipe network of the garbage incineration power generation boiler, and belongs to the garbage incineration power generation boiler control technology. According to a calculation mathematical model of an external air entering amount of the garbage incineration power generation boiler, a calculation mathematical model of an excess air coefficient, a dynamic control method of the external air entering amount and the excess air coefficient, the external air entering amount of the garbage incineration power generation boiler is calculated through argon content of flue gas analysis and detection, then a difference between a set value of the external air entering amount and a calculation value of the external air entering amount is used to adjust an inlet valve opening degree of an induced draft fan, so that the external air entering amount is always controlled in a set value range; according to oxygen content and carbon monoxide content of flue gas analysis and detection, a secondary air fan air volume and a primary air fan air volume are adjusted, so that the excess air coefficient is always controlled in a set value range; and multiple energy-saving and emission-reducing effects of improving boiler thermal efficiency, reducing NOx and VOC pollution emission amount and realizing full-automatic control are obtained.

Description

Technical Field

[0001] This invention pertains to the control technology of waste incineration power generation boilers, specifically the control technology of external air intake and excess air coefficient of waste incineration power generation boilers; this invention does not involve the selection of control systems, control equipment, and instruments. Background Technology

[0002] Waste-to-energy incineration is a promising comprehensive resource utilization project. On the one hand, it can improve the diversification of my country's energy supply structure, and on the other hand, it provides a new sustainable development model for regional pollutant control and maintaining ecological environment quality.

[0003] Compared to traditional power plant boilers, waste-to-energy incineration systems face greater challenges in control due to the wide variety of raw materials, quantities, and qualities, complex combustion conditions within the incinerator, and numerous unstable factors. The main problems with existing technologies for waste-to-energy boilers are low combustion efficiency and difficulty in maintaining stable furnace pressure. A deeper issue is the lack of control over flue gas oxygen content and excess air coefficient, which directly impacts the economic benefits and pollutant reduction effectiveness of power plants.

[0004] Unlike traditional power plant boilers, waste-to-energy incineration boilers have high requirements for the oxidizing atmosphere inside the furnace. A suitable oxidizing atmosphere helps the waste to burn completely, which not only improves the boiler's thermal efficiency but also effectively controls nitrogen oxides (NOx). X The emission of harmful gases such as volatile organic compounds (VOCs) and dioxins makes dynamic control of the excess air coefficient crucial for waste incineration power generation boilers.

[0005] Unfortunately, to date, waste-to-energy boilers still lack dynamic control technology for the oxidizing atmosphere inside the furnace. Due to the lack of control over the oxygen content and excess air coefficient in the flue gas, existing technologies are fundamentally unable to meet the needs of deep energy conservation and emission reduction in waste-to-energy boilers. Breakthroughs in theoretical research and applied technologies are urgently needed.

[0006] No publicly available publications, documents, or materials have been found regarding dynamic control methods for the asymmetric characteristics of waste incineration power generation boilers and their flue gas pipelines. Summary of the Invention

[0007] The purpose of this invention is to seek breakthroughs in the technical bottlenecks that restrict existing technologies based on the characteristics of the operating conditions of waste incineration power generation boilers, and to research and develop a dynamic control method for the asymmetric characteristics of waste incineration power generation boilers and their flue gas pipelines that is adapted to the operating conditions of waste incineration power generation boilers, so as to achieve the effect of deep energy saving and emission reduction of waste incineration power generation boilers.

[0008] The key point of this invention is to address the problems existing in current technologies, break through their foundations and frameworks, and, based on the operating characteristics of waste-to-energy incineration boilers and the physical properties of their flue gas pipelines, innovatively establish an asymmetric system theory for waste-to-energy incineration boilers. Mathematical models for calculating the external air intake and excess air coefficient of waste-to-energy incineration boilers are developed. A dynamic control method for the external air intake and excess air coefficient based on this asymmetric system theory is also developed. The external air intake is calculated using argon content detected through flue gas analysis. Then, the opening of the induced draft fan inlet valve is adjusted based on the difference between the set value and the calculated value of the external air intake, thus constituting a dynamic control method for waste-to-energy incineration boilers. The closed-loop dynamic adjustment system for the external air intake of the power generation boiler ensures that the external air intake is always controlled within the set value range. Based on the oxygen and carbon monoxide content detected by flue gas analysis, the airflow of the secondary and primary air fans is adjusted to control the excess air coefficient of the waste-to-energy power generation boiler. This constitutes a closed-loop dynamic adjustment system for the excess air coefficient, ensuring that the excess air coefficient is always controlled within the set value range. Effective control of the external air intake and excess air coefficient achieves multiple energy-saving and emission-reduction effects, including improved thermal efficiency of the waste-to-energy power generation boiler, reduced total flue gas production, increased energy savings for the induced draft fan, reduced NOx and VOC emissions, fully automated control of the waste-to-energy power generation boiler, reduced operator workload, and increased production efficiency. This results in multiple benefits of energy conservation, emission reduction, increased production, and guaranteed quality. Attached Figure Description

[0009] Figure 1 This is a block diagram of a technical solution for dynamic control of the asymmetric characteristics of waste incineration power generation boilers and their flue gas pipelines. Figure 1 1 is the HMI control station of the waste-to-energy incineration boiler control system; 2 is the external air intake setpoint; 3 is the induced draft fan inlet valve opening adjustment; 4 is the mathematical model for calculating the external air intake of the waste-to-energy incineration boiler; 5 is the Ar content detection in the flue gas; 6 is the flue gas flow detection; 7 is the primary air fan air volume detection; 8 is the secondary air fan air volume detection; 9 is the proportion coefficient k input; 10 is the mathematical model for calculating the excess air coefficient of the waste-to-energy incineration boiler; 11 is the excess air coefficient setpoint; 12 is the O2 content detection in the flue gas; 13 is the secondary air fan air volume adjustment; 14 is the air-fuel ratio; 15 is the furnace temperature setpoint; 16 is the actual furnace temperature; 17 is the primary air fan air volume adjustment; 18 is the CO setpoint of the waste-to-energy incineration boiler; 19 is the actual CO value in the flue gas; 20 is the furnace pressure setpoint; 21 is the induced draft fan air volume adjustment; 22 is the actual furnace pressure; and 23 is the on-site process equipment of the waste-to-energy incineration boiler.

[0010] Figure 2This is a control system configuration diagram of a dynamic control method for the asymmetric characteristics of a waste-to-energy incineration boiler and its flue gas pipeline network. Figure 2 1 is the main process control system of the waste-to-energy incineration boiler; 2 is the HMI operator station of the waste-to-energy incineration boiler control system; 3 is the external air intake setpoint; 4 is the excess air coefficient setpoint; 5 is the CO setpoint of the waste-to-energy incineration boiler; 6 is the furnace pressure setpoint; 7 is the furnace temperature setpoint; 8 is the air-fuel ratio setpoint input; 9 is the proportion coefficient k input; 10 is the dynamic controller of the asymmetric system of the waste-to-energy incineration boiler and its flue gas pipeline; 11 is the Ar content detection in the flue gas; 12 is the O2 content detection in the flue gas; 13 is the CO content detection in the flue gas; 14 is the flue gas flow rate detection; 15 is the primary air fan air volume detection; 16 is the secondary air fan air volume detection; 17 is the furnace pressure detection; 18 is the furnace temperature detection; 19 is the induced draft fan inlet valve opening adjustment; 20 is the induced draft fan air volume adjustment; 21 is the primary air fan air volume adjustment; 22 is the secondary air fan air volume adjustment; 23 is the process information of the on-site process equipment; 24 is the on-site process equipment of the waste-to-energy incineration boiler.

[0011] Figure 1 The system is constructed based on the general characteristics of waste-to-energy incineration boilers. In reality, there are many types of waste-to-energy incineration boilers, with various process parameters and equipment layouts. To avoid tedious descriptions and confusion, the description of this technical solution is only for the purpose of explaining the control principle. Therefore, it considers general cases with common characteristics without distinguishing the details of the specific waste-to-energy incineration boiler process and equipment composition. However, the control principle, conclusions, and beneficial effects described in this paper are suitable for the application of waste-to-energy incineration boilers operating under slight negative pressure in the furnace. Detailed Implementation

[0012] Basic terms and definitions: The excess air coefficient in a waste-to-energy boiler system, also known as the excess air coefficient or excess air coefficient, is defined as "the ratio of the actual air requirement to the theoretical air requirement during fuel combustion", denoted by the letter α.

[0013] By definition, the excess air coefficient refers to the result obtained by the combustion system of a waste-to-energy incineration boiler at a set air-fuel ratio, that is, the combustion effect of combustion air and fuel under that air-fuel ratio condition. This combustion effect does not include the effect of combustion caused by external air entering the waste-to-energy incineration boiler. Although external air entering the waste-to-energy incineration boiler may result in partial or complete combustion, compared with an air-fuel ratio-based combustion system, the external air entering the waste-to-energy incineration boiler is cold air, which will cause heat loss and thus have a negative impact, which is not conducive to improving the thermal efficiency of the waste-to-energy incineration boiler. The oxidizing atmosphere caused by excess air will also increase NOx and VOC emissions. The excess air coefficient and the amount of external air entering the waste-to-energy incineration boiler have different meanings. Therefore, the oxygen content detected in the flue gas network does not represent the excess air coefficient or the amount of external air entering the boiler; the oxygen content is a mixture of both.

[0014] The existing method for controlling the excess air coefficient in waste-to-energy boilers is to calculate and estimate the excess air coefficient value based on the detected oxygen and carbon monoxide content in the flue gas. Different types of waste-to-energy boilers have recommended excess air coefficient ranges or limits to guide operators in manually adjusting the excess air coefficient. However, this method is actually not advisable.

[0015] The reason is:

[0016] First, there are problems with the current understanding of the excess air coefficient in waste-to-energy incineration boilers. According to the definition of the excess air coefficient, the so-called excess air coefficient obtained by detecting the oxygen content in flue gas using current technology is not a true excess air coefficient because it includes the oxygen content of the external air entering the boiler. The true excess air coefficient refers to the result of combustion after setting the air-fuel ratio, and does not include the oxygen content of the external air entering the boiler. This concept is supported by the new version of the Boiler Air Pollutant Emission Standard GB13271-2014. The new national standard uses the term "baseline oxygen content" for pollutant emission concentration, instead of the "excess air coefficient" in the original national standard GB13271-2001. That is, the oxygen content detected in the flue gas is not equal to the "excess air coefficient," correcting the previous ambiguous concept. Previously, calculating the "excess air coefficient" based on the oxygen content detected in the flue gas also lacked theoretical basis, and current technology lacked an accurate method for calculating the "excess air coefficient." Therefore, the current national standard's use of "baseline oxygen content" for pollutant emission concentration is a wise move to avoid misleading consumers.

[0017] Second, misunderstandings make it difficult to implement existing technologies. Because there is no theoretical basis for specific guidance, operators can only rely on experience and make adjustments experimentally based on the recommended range or limit of the excess air coefficient. It is difficult to obtain the expected results. In fact, the current control of waste incineration power generation boiler systems lacks dynamic automatic control function for the excess air coefficient.

[0018] Dynamic control of excess air coefficient in waste-to-energy incineration boilers is a typical and long-standing industrial control problem. It is a common issue for waste-to-energy incineration boilers with similar operating conditions and is considered a complex industrial system control problem, making it highly representative. To date, existing technologies have not found a method for dynamic control of excess air coefficient in waste-to-energy incineration boilers, and remain at the level of manual adjustment or automatic + manual intervention control methods where the control strategy is not entirely correct.

[0019] The oxygen content measured in flue gas does not represent the excess air coefficient α. Using oxygen content to represent or convert the excess air coefficient for combustion control will produce erroneous results. The following is a qualitative analysis of the hazards that existing control strategies may cause.

[0020] Let the oxygen content detected in the flue gas be A. Since the oxygen in the flue gas consists of two parts: one is the residual oxygen caused by an improper air-fuel ratio, denoted as B; the other is the oxygen brought in by external air entering the furnace, denoted as C. B has three possible scenarios: α > 1, α = 1, and α < 1. C, however, only has one possible scenario: based on the fundamental characteristics of waste incineration power generation boilers, it's impossible for no external air to enter at all. Therefore, there is no case where oxygen = zero; only the case where oxygen > 0 exists. If we consider that C may partially burn, completely burn, or not burn with CO in the flue gas... Combustion and the reaction of C with nitrogen at high temperatures to produce NOx are considered as part of the oxygen lost through combustion and reaction, which is represented by D. Based on these conditions, the oxygen measured in the flue gas is a combination of two oxygen components, B and C. There are three possible combinations to form A: the first is when α > 1, B and C mix, so A = B + CD; the second is when α = 1, i.e., the air-fuel ratio is 1, in which case B is zero, so A = CD; the third is when α < 1, i.e., the remaining oxygen in B is zero, but there is remaining CO, so A = CD.

[0021] The existing technology controls based on A. In the first case, the operator adjusts the combustion air to decrease or increase the gas ratio, thus reducing B. However, the control is actually based on A. Since A > B, the result of the control will be α < 1. In the second case, since the air-fuel ratio is 1, the operator adjusts the combustion air to decrease or increase the gas ratio, and the result of the control will inevitably be α < 1. In the third case, the result of the control is the same as the second case, which will also be α < 1. The difference is that the combustion situation is even worse.

[0022] Based on the above analysis, according to the existing technology's control strategy based on A, the control result will always be α < 1 regardless of the situation. Therefore, compared with the state before control, combustion deterioration is inevitable, resulting in increased fuel consumption, decreased furnace thermal efficiency, and increased NOx emissions. Thus, the existing technology's control strategy is not advisable.

[0023] So, how can combustion optimization control be achieved? How can the thermal efficiency of waste incineration power generation boilers be improved? What are the key issues with existing technologies? How can the problems of existing technologies be specifically solved? The following invention will provide theoretical analysis, conclusions, control strategies, and technical solutions.

[0024] Theoretical Analysis:

[0025] When technology encounters a bottleneck, there are inevitably fatal obstacles. To overcome this bottleneck, one must have a mindset different from that of existing technologies, break free from the constraints of the existing technological framework, and importantly, re-examine the essence of the controlled object—that is, to overturn the incorrect understanding of the controlled object by existing technologies.

[0026] First, let's analyze the general situation of furnaces and kilns. As the process parameters or production load change, the amount of furnace gas generated in the furnace and kiln also changes. As the production load increases or decreases, the amount of furnace gas also increases or decreases. However, furnaces and kilns have a common characteristic: without external pre-application of control, when the amount of furnace gas increases, the furnace pressure will rise; when the amount of furnace gas decreases, the furnace pressure will not decrease, but will remain at the original state. This phenomenon in furnaces and kilns is formed by the characteristics of the furnace and kiln equipment itself and the characteristics of the flue gas pipeline network. The furnace and kiln equipment is not a very tight closed system and usually operates in a state of slight negative pressure in the furnace. The furnace gas generated in the furnace and kiln is discharged from the flue gas pipeline network under the action of the induced draft fan. When the furnace load increases, the gas flow rate increases, and the furnace pressure rises. The furnace pressure detection and regulation system controls the induced draft fan speed or the opening of the induced draft fan inlet valve to change the flue gas output flow rate and balance the pressure. When the furnace load decreases, the gas flow rate decreases, but the furnace pressure does not change, or does not change significantly. This is because as the gas flow rate gradually decreases, the reduced portion is gradually filled by air entering from outside the furnace and the flue gas generated there, so the furnace pressure remains in equilibrium. In this case, the furnace pressure detection and regulation system does not activate furnace pressure regulation. This phenomenon in the furnace is called an "asymmetric system" process.

[0027] "Asymmetric systems" are highly deceptive and misleading, thus obscuring and deceiving existing technologies. Consider this: existing technologies employ the conventional symmetric control strategy to control asymmetric systems, regulating furnace pressure through a closed-loop system based on furnace pressure detection. This effectively creates a one-sided regulation phenomenon—it only regulates when the gas flow increases, not when it decreases. If the system repeats this cycle of increasing and decreasing gas flow several times, the furnace pressure regulation system will collapse or enter an unstable operating state. This is the long-standing problem of unstable furnace pressure control in furnaces. For furnaces with relatively stable production loads, although the displayed furnace pressure fluctuates within a small range, giving the impression of good control, the oxygen content detected in the flue gas confirms that the furnace pressure is actually under control. Beneath the surface of stable power, the oxygen content of the system has actually deteriorated, indicating that the existing technology is in a state of loss of control over the amount of external air entering the system. At the same time, the increase in oxygen content has misled the existing technology to manually adjust the excess air coefficient, causing the combustion system, which was originally operating stably, to enter a chaotic state. This has affected the temperature control and caused disorder. This is the root cause of the difficulty in stabilizing the furnace temperature system that has been encountered in the furnace for a long time. However, the existing technology has not realized the impact of the "asymmetric system". Instead, it has attributed the difficulty in stabilizing the furnace temperature system to factors such as the instability of the combustion medium pipeline pressure and the changes in the composition of the combustion medium. Therefore, the temperature control strategy adopted is contrary to the objective reality, which has led to the passive situation of the furnace temperature system being difficult to stabilize.

[0028] Waste-to-energy incineration boilers are also a type of furnace and possess the general characteristics of furnaces. Therefore, the asymmetric characteristics of furnaces also exist in waste-to-energy incineration boilers, directly affecting the stable control of furnace pressure and temperature. What distinguishes waste-to-energy incineration boilers from general furnaces is that they are a type of furnace with more complex operating conditions, featuring different processes and equipment.

[0029] Technical solutions:

[0030] Theoretically speaking, the theory of asymmetric furnace systems, which reveals the physical characteristics of furnaces and their flue gas pipelines, lays the theoretical foundation for realizing dynamic control of furnace pressure and temperature in waste incineration power generation boilers. The next step is to specifically solve the problems that existing technologies have not solved or cannot solve.

[0031] Current technologies have not solved the problem of dynamic control of excess air coefficient in waste-to-energy incineration boilers. In particular, they have not recognized the impact of the amount of external air entering the boiler on the control of furnace pressure and temperature, let alone how to solve this problem. They are still limited to detecting oxygen content through flue gas analysis, converting it into a so-called excess air coefficient, and then having operators manually adjust the combustion air volume. In reality, since the oxygen content detected by flue gas analysis does not represent the true excess air coefficient, and the so-called optimal excess air coefficient obtained by system tests or simulation calculations is also conducted under incorrect conditions, the excess air coefficient obtained by current technologies and the control strategies adopted have serious technical flaws. Therefore, current technologies cannot achieve dynamic automatic control of the excess air coefficient.

[0032] The key to solving this problem lies in the correct analysis and accurate calculation of the excess air coefficient. The oxygen content detected in the flue gas is partly due to an improper air-fuel ratio in the combustion system, resulting in an excessively high excess air coefficient and excess oxygen. Another part is the oxygen contained in the air entering the waste-to-energy incineration boiler after combustion or uncombustion within the boiler and its piping network. Accurately calculating the oxygen content of each component is the crucial issue this technical solution needs to address. To determine the oxygen content related to the excess air coefficient, we must first calculate the oxygen content of the air entering the waste-to-energy incineration boiler. Then, subtracting the oxygen content of the air entering the boiler from the oxygen content measured in the flue gas yields the oxygen content related to the excess air coefficient. To calculate the oxygen content of the air entering the boiler, we first need to know the amount of air entering the boiler. This leads to the development of dynamic control technology for the amount of air entering the waste-to-energy incineration boiler, another innovative technology representing a qualitative leap forward compared to existing technologies.

[0033] To control the amount of external air entering the boiler, it is first necessary to accurately calculate the amount of external air entering. Therefore, this invention develops a mathematical model (1) for calculating the amount of external air entering the boiler for waste incineration power generation:

[0034]

[0035] In the formula:

[0036] Q f Airflow rate of the primary air fan, m 3 / s;

[0037] Q s Airflow rate of the secondary air fan, in meters (m) 3 / s;

[0038] A rb : Standard argon mole fraction in air, mol%.

[0039] Q w Flue gas flow rate, m 3 / s;

[0040] A rw Argon mole fraction in flue gas, mol%.

[0041] Q air The amount of air entering the waste-to-energy boiler, in meters. 3 / s.

[0042] Based on the characteristic that inert gases are difficult to participate in chemical reactions, the amount of external air entering the waste-to-energy boiler is calculated by detecting inert gases in the flue gas, which can ensure the accuracy of the calculation. This technical solution uses argon as the basis for flue gas analysis and calculation, but it is not limited to using argon for different types of waste-to-energy boilers in actual applications.

[0043] After accurately calculating the amount of external air entering the waste incineration power plant using the mathematical model for calculating the amount of external air entering the waste incineration power plant, the oxygen content can be analyzed and calculated. According to equation (1), equation (2) can be derived as the mathematical model for calculating the oxygen content in the amount of external air entering the waste incineration power plant.

[0044]

[0045] In the formula:

[0046] Q f Airflow rate of the primary air fan, m 3 / s;

[0047] Q s Airflow rate of the secondary air fan, in meters (m) 3 / s;

[0048] A rb : Standard argon mole fraction in air, mol%.

[0049] Q w Flue gas flow rate, m 3 / s;

[0050] A rw Argon mole fraction in flue gas, mol%.

[0051] O 2e Oxygen content in the amount of external air entering a waste-to-energy incineration boiler, in mol;

[0052] The actual oxygen content in the excess air coefficient can be obtained by subtracting the oxygen content in the external air intake calculated by the mathematical model of equation (2) from the oxygen content detected in the flue gas. This value is calculated by the mathematical model of the excess air coefficient in equation (3).

[0053]

[0054] In the formula:

[0055] O 2a : Actual oxygen content in the excess air coefficient, %;

[0056] Q w Flue gas flow rate, m 3 / s;

[0057] O 21 : Mole fraction of oxygen in flue gas, mol%.

[0058] O 2e Oxygen content in the amount of external air entering a waste-to-energy incineration boiler, in mol;

[0059] k: Proportion coefficient, 0~1;

[0060] In equation (3), k represents the percentage of oxygen remaining in the incoming external air when it reaches the flue gas detection point, i.e., the proportion of remaining oxygen to the total oxygen in the incoming external air, referred to as the percentage coefficient, which ranges from 0 to 1; because the amount of oxygen entering from the outside is O 2e The possibility of unburned, partially burned, or completely burned is a variable related to the air leakage of the waste-to-energy boiler and its flue gas pipeline network. It cannot be accurately calculated mathematically, so an engineering coefficient method is adopted to solve the problem. The proportion coefficient k is determined by the waste-to-energy boiler process engineer based on the detection statistics of the amount of external air entering the boiler body and the air leakage of the flue gas pipeline network, and is entered into the HMI operation station.

[0061] Substituting equation (3) into the simplified mathematical model for calculating the excess air coefficient (4), we obtain equation (5) for calculating the excess air coefficient.

[0062]

[0063] In the formula:

[0064] O 2a : Actual oxygen content in the excess air coefficient, %;

[0065] α: Excess air coefficient, >0.

[0066]

[0067] In the formula:

[0068] Q w Flue gas flow rate, m 3 / s;

[0069] O 21: Mole fraction of oxygen in flue gas, mol%.

[0070] O 2e Oxygen content in the amount of external air entering a waste-to-energy incineration boiler, in mol;

[0071] k: Proportion coefficient, 0~1;

[0072] α: Excess air coefficient, >0.

[0073] With the mathematical models of equations (1), (2), (3), (4) and (5), the dynamic control problem of waste incineration power generation boilers is solved based on the theory of asymmetric furnace and kiln systems and the adoption of corresponding control strategies.

[0074] Figure 1 This is a block diagram of a technical solution for dynamic control of the asymmetric characteristics of waste incineration power generation boilers and their flue gas pipelines. Figure 1The HMI operation station (1) of the waste-to-energy incineration boiler control system is the human-machine interface of the dynamic control system for the asymmetric characteristics of the waste-to-energy incineration boiler and its flue gas pipeline network; the external air intake setting value (2) is connected to the HMI operation station (1) of the waste-to-energy incineration boiler control system and the induced draft fan inlet valve opening adjustment (3), and this setting value is input by the human-machine interface; the induced draft fan inlet valve opening adjustment (3) is connected to the external air intake setting value (2), the mathematical model (4) for calculating the external air intake of the waste-to-energy incineration boiler, and the on-site process equipment (23) of the waste-to-energy incineration boiler, and is controlled by the external air intake setting value (2). The difference between the set value of air intake (2) and the mathematical model (4) for calculating the external air intake of the waste incineration power plant is used to adjust the opening of the induced draft fan inlet valve, control the flow rate of flue gas flowing through the inlet valve, suppress the entry of external air, and keep the external air intake of the waste incineration power plant within the set value range; the mathematical model (4) for calculating the external air intake of the waste incineration power plant is used in conjunction with the detection of Ar content in flue gas (5), flue gas flow rate (6), primary fan air volume (7), secondary fan air volume (8), mathematical model (10) for calculating the excess air coefficient of the waste incineration power plant, and the induced draft fan. The inlet valve opening adjustment (3) is connected to calculate the amount of external air entering the waste incineration power plant based on the Ar content in the flue gas, flue gas flow rate, primary fan volume, and secondary fan volume. The calculation results are sent to the induced draft fan inlet valve opening adjustment (3) and the mathematical model (10) for calculating the excess air coefficient of the waste incineration power plant. The Ar content detection (5) in the flue gas is connected to the mathematical model (4) for calculating the amount of external air entering the waste incineration power plant and the on-site process equipment (23) of the waste incineration power plant. The flue gas flow rate detection (6) is connected to the mathematical model (4) for calculating the amount of external air entering the waste incineration power plant. The primary air fan air volume detection (7) is connected to the external air intake calculation mathematical model (4) of the waste incineration power generation boiler and the waste incineration power generation boiler on-site process equipment (23); the secondary air fan air volume detection (8) is connected to the external air intake calculation mathematical model (4) of the waste incineration power generation boiler and the waste incineration power generation boiler on-site process equipment (23); the proportion coefficient k input (9) is connected to the waste incineration power generation boiler control system HMI operation station (1) and the waste incineration power generation boiler excess air coefficient calculation mathematical model (10);The mathematical model for calculating the excess air coefficient of a waste-to-energy incineration boiler (10) is connected with the mathematical model for calculating the amount of external air entering the waste-to-energy incineration boiler (4), the excess air coefficient setpoint (11), the detection of O2 in the flue gas (12), and the secondary fan airflow adjustment (13). Based on the mathematical model for calculating the amount of external air entering the waste-to-energy incineration boiler, the mathematical model for calculating the excess air coefficient of the waste-to-energy incineration boiler is derived. The difference between the excess air coefficient setpoint and the calculated value of the excess air coefficient of the waste-to-energy incineration boiler is used to adjust the airflow of the secondary fan, thereby dynamically adjusting the excess air coefficient of the waste-to-energy incineration boiler. Control; the excess air coefficient setpoint (11) is the setpoint, input by the human-machine interface of the waste-to-energy boiler control system HMI operation station (1); the O2 content detection (12) in the flue gas is the actual value of O2 content, which is used as feedback value to participate in the calculation of the excess air coefficient; the secondary air fan airflow adjustment (13) is the controlled variable, and the difference in the excess air coefficient calculation is used to adjust the secondary air fan airflow to adjust the excess air coefficient; the air-fuel ratio (14) is input from the human-machine interface of the waste-to-energy boiler control system HMI operation station (1); the furnace temperature setpoint (15) is the setpoint, input by the waste-to-energy boiler control system The HMI operation station (1) inputs the following: the actual furnace temperature (16) is the furnace temperature control feedback value; the primary air fan airflow adjustment (17) is the controlled variable, which adjusts the primary air fan airflow according to the difference between the furnace temperature setpoint and the actual furnace temperature to dynamically control the furnace temperature; the waste incineration power generation boiler CO setpoint (18) is the setpoint, which is input by the waste incineration power generation boiler control system HMI operation station (1) human-machine interface; the actual CO value in the flue gas (19) is the actual CO detection value, which is used as negative feedback and compared with the waste incineration power generation boiler CO setpoint (18). The difference is used to adjust the primary air fan volume to improve combustion; the furnace pressure setpoint (20) is a setpoint input by the human-machine interface of the waste-to-energy boiler control system HMI operator station (1); the induced draft fan volume adjustment (21) is connected to the furnace pressure setpoint (20), the actual furnace pressure (22), and the waste-to-energy boiler on-site process equipment (23), and adjusts the induced draft fan volume according to the feedback difference between the furnace pressure setpoint and the actual furnace pressure, thereby dynamically controlling the furnace pressure; the waste-to-energy boiler on-site process equipment (23) is the waste-to-energy boiler on-site online equipment.

[0075] This technical solution is passed Figure 2 The control system configuration diagram of the dynamic control method for the asymmetric characteristics of the waste incineration power generation boiler and its flue gas pipeline network shown is implemented. Figure 2The main process control system (1) of the waste-to-energy incineration boiler is the main control system of the waste-to-energy incineration boiler, including the control of the waste-to-energy incineration boiler body and its auxiliary equipment, and is connected to the dynamic controller (10) of the asymmetric system of the waste-to-energy incineration boiler and its flue gas pipeline network; the HMI operation station (2) of the waste-to-energy incineration boiler control system is a computer-based human-machine interface for operation and screen display, and is connected to the dynamic controller (10) of the asymmetric system of the waste-to-energy incineration boiler and its flue gas pipeline network; the external air intake setpoint (3) is the system control target setpoint, which comes from the HMI operation station (2) of the waste-to-energy incineration boiler control system and is sent to the dynamic controller (10) of the asymmetric system of the waste-to-energy incineration boiler and its flue gas pipeline network. Controller (10); Excess air coefficient setpoint (4) is the system control target setpoint, which is sent from the waste-to-energy boiler control system HMI operation station (2) to the waste-to-energy boiler and its flue gas network asymmetric system dynamic controller (10); Waste-to-energy boiler CO setpoint (5) is the system control target setpoint, which is sent from the waste-to-energy boiler control system HMI operation station (2) to the waste-to-energy boiler and its flue gas network asymmetric system dynamic controller (10); Furnace pressure setpoint (6) is the system control target setpoint, which is sent from the waste-to-energy boiler control system HMI operation station (2) to the waste-to-energy boiler and its flue gas network asymmetric system dynamic controller (10); The system dynamic controller (10) is called the furnace temperature setpoint (7), which is the system control target setpoint. The setpoint is sent from the waste-to-energy boiler control system HMI operation station (2) to the waste-to-energy boiler and its flue gas network asymmetric system dynamic controller (10); the air-fuel ratio setpoint input (8) is the system control setpoint. The setpoint is sent from the waste-to-energy boiler control system HMI operation station (2) to the waste-to-energy boiler and its flue gas network asymmetric system dynamic controller (10); the proportion coefficient k input (9) is the mathematical model calculation parameter. It is sent from the waste-to-energy boiler control system HMI operation station (2) to the waste-to-energy boiler and its flue gas network asymmetric system dynamic controller (10). 10); The dynamic controller (10) of the waste-to-energy incineration boiler and its flue gas pipeline network asymmetric system is the core of the dynamic control of the waste-to-energy incineration boiler and its flue gas pipeline network asymmetric system. It is composed of DCS or similar digital controllers. It has its own mathematical model for calculating the amount of external air entering the waste-to-energy incineration boiler, mathematical model for calculating the excess air coefficient of the waste-to-energy incineration boiler, closed-loop dynamic control of the amount of external air entering the waste-to-energy incineration boiler, and closed-loop dynamic control software for the excess air coefficient of the waste-to-energy incineration boiler; the Ar content detection (11) in the flue gas is the actual value of the flue gas detection, which is sent to the dynamic controller (10) of the waste-to-energy incineration boiler and its flue gas pipeline network asymmetric system for the mathematical model to calculate the amount of external air entering;The O2 content detection (12) in the flue gas is the O2 content detection value of the flue gas, which is sent to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for mathematical model calculation of the oxygen content in the external air intake; the CO content detection (13) in the flue gas is the CO content detection value of the flue gas, which is sent to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for adjusting the primary air fan flow rate and controlling the CO content; the flue gas flow rate detection (14) is the actual value of the flue gas flow rate, which is connected to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for mathematical model calculation of the external air intake; The secondary airflow detection (15) is the primary airflow detection value, which is sent to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for mathematical model calculation of the amount of external air entering; the secondary airflow detection (16) is the secondary airflow detection value, which is sent to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for mathematical model calculation of the amount of external air entering; the furnace pressure detection (17) is the actual furnace pressure detection value, which is sent to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for adjusting the induced draft fan airflow and dynamically controlling the furnace pressure; the furnace temperature detection (18) The actual value of the furnace temperature is sent to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for dynamic adjustment of the furnace temperature; the induced draft fan inlet valve opening adjustment (19) is connected to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for adjusting the opening of the induced draft fan inlet valve to suppress the entry of external air and control the amount of external air entering; the induced draft fan air volume adjustment (20) is connected to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for dynamic adjustment of the furnace pressure; the primary air fan air volume adjustment (21) is connected to the dynamic controller (10) of the asymmetric system of the waste incineration power generation boiler and its flue gas pipeline network for dynamic adjustment of the furnace pressure; The system dynamic controller (10) is connected to the waste-to-energy incineration boiler for temperature and CO regulation; the secondary air fan air volume regulator (22) is connected to the waste-to-energy incineration boiler and its flue gas pipeline asymmetric system dynamic controller (10) for temperature and excess air coefficient regulation; the on-site process equipment process information (23) collects the operating signals and status information of the equipment and detectors of the on-site process equipment (24) of the waste-to-energy incineration boiler and sends them to the waste-to-energy incineration boiler and its flue gas pipeline asymmetric system dynamic controller (10); the on-site process equipment (24) of the waste-to-energy incineration boiler is the on-site online equipment of the waste-to-energy incineration boiler.

[0076] To improve the thermal efficiency of waste-to-energy incineration boilers, it is necessary to control both the excess air coefficient and the amount of external air entering the boiler. Controlling the excess air coefficient optimizes combustion performance, while controlling the amount of external air entering the boiler reduces heat loss and stabilizes pressure. Achieving these two controllable aspects breaks through the technical bottlenecks that restrict existing technologies, enabling dynamic automatic control of the asymmetric system of waste-to-energy incineration boilers.

[0077] ① Dynamic control system for external air intake of waste incineration power generation boiler

[0078] In the mathematical model calculation of the external air intake of a waste-to-energy incineration boiler, detecting the argon content in the flue gas to calculate the external air intake is a simple, accurate, and reliable method. The opening of the induced draft fan inlet valve is adjusted based on the deviation between the set value and the calculated value of the external air intake, ensuring that the valve opening is basically matched with the actual flue gas volume of the boiler, thus suppressing external air intake. Furthermore, the speed of the induced draft fan is adjusted by detecting the furnace pressure, achieving dynamic control of the furnace pressure. This solves the problem of uncontrollable asymmetric systems in waste-to-energy incineration boilers, even in waste-to-energy incineration... When the boiler load decreases, the dynamic control system for the amount of external air entering the waste-to-energy boiler adjusts the opening of the induced draft fan inlet valve to reduce the furnace pressure. The furnace pressure regulation system then adjusts the induced draft fan speed to achieve a new balance in the furnace pressure. The pressure disturbance caused by the load change of the waste-to-energy boiler is effectively controlled, preventing pressure runaway. When the opening of the induced draft fan inlet valve is basically matched with the actual furnace gas volume, the characteristics of the fan network are also well improved, the speed range of the induced draft fan is greatly improved, and the fan surge problem is eliminated, meeting the energy-saving optimization requirements of the induced draft fan across all operating conditions.

[0079] Stable furnace pressure is one of the necessary conditions for the normal operation of waste-to-energy incineration boilers. Only when the amount of external air entering the boiler is effectively controlled can the furnace pressure be stably controlled. In other words, the external air entering the boiler due to its asymmetric characteristics significantly affects the stability of the furnace pressure. Under the premise of controlling the opening of the induced draft fan inlet valve according to the amount of external air entering the boiler, the key technology for regulating the asymmetric system of the waste-to-energy incineration boiler is to control the speed of the induced draft fan by detecting the furnace pressure.

[0080] Figure 1The technical solution block diagram of the dynamic control method for the asymmetric characteristics of the waste incineration power generation boiler and its flue gas pipeline network consists of the following components: the HMI operation station of the waste incineration power generation boiler control system (1), the external air intake setpoint (2), the induced draft fan inlet valve opening adjustment (3), the mathematical model for calculating the external air intake of the waste incineration power generation boiler (4), the detection of Ar content in the flue gas (5), the flue gas flow detection (6), the primary air fan air volume detection (7), the secondary air fan air volume detection (8), the furnace pressure setpoint (20), the induced draft fan air volume adjustment (21), the actual furnace pressure value (22), and the on-site process equipment of the waste incineration power generation boiler (23). These components constitute the closed-loop dynamic control system for the external air intake of the waste incineration power generation boiler.

[0081] ② Dynamic control system for excess air coefficient of waste incineration power generation boiler

[0082] The method involves detecting the oxygen and carbon monoxide content in the flue gas, calculating the excess air coefficient based on a mathematical model for calculating the excess air coefficient of a waste incineration power generation boiler, and then adjusting the secondary air fan volume based on the difference between the set value and the calculated value of the excess air coefficient, as well as adjusting the primary air fan volume based on the difference between the detected CO value and the set CO value, so that the excess air coefficient is stabilized within the set value range.

[0083] Figure 1 The technical solution block diagram of the dynamic control method for the asymmetric characteristics of the waste incineration power generation boiler and its flue gas pipeline network consists of the following components: the HMI operation station of the waste incineration power generation boiler control system (1), the proportion coefficient k input (9), the mathematical model for calculating the excess air coefficient of the waste incineration power generation boiler (10), the excess air coefficient setpoint (11), the O2 content detection in the flue gas (12), the secondary air fan air volume adjustment (13), the air-fuel ratio (14), the furnace temperature setpoint (15), the actual furnace temperature value (16), the primary air fan air volume adjustment (17), the CO setpoint of the waste incineration power generation boiler (18), the actual CO value in the flue gas (19), and the on-site process equipment of the waste incineration power generation boiler (23). These components constitute the closed-loop dynamic control system for the excess air coefficient of the waste incineration power generation boiler.

[0084] In practical engineering applications, the amount of external air entering the waste-to-energy boiler cannot be zero, the excess air coefficient cannot be 1, and the amount of CO in the flue gas cannot be zero. Therefore, set values ​​for the amount of external air entering the waste-to-energy boiler, the excess air coefficient, and the CO of the waste-to-energy boiler are set separately. These set values ​​are determined by the waste-to-energy boiler process engineer based on the specific operating conditions of the waste-to-energy boiler and are input into the HMI operator station of the control system.

[0085] Regarding the external air intake of the waste-to-energy incineration boiler, the pipeline leakage can be determined experimentally during system commissioning or equipment maintenance. Specifically, the dynamic control system for external air intake is adjusted to bring the boiler furnace pressure to zero. The argon content measured by flue gas analysis is used to calculate the external air intake. This calculated external air intake is the pipeline leakage. The pipeline leakage calculation result is displayed on the HMI (Human-Machine Interface) station. The pipeline leakage is used for excess air coefficient calculation and equipment maintenance guidance. If the calculated pipeline leakage is too high, equipment maintenance should be organized as soon as possible.

[0086] Because flue gas overflow from waste-to-energy boilers can increase boiler heat loss, damage boiler auxiliary equipment, increase flue gas volume, and make it difficult to calculate the excess air coefficient of waste-to-energy boilers, micro-positive pressure control is not suitable for waste-to-energy boilers. Instead, micro-negative pressure control should be adopted.

[0087] The dynamic control method for asymmetric systems of waste-to-energy incineration boilers is characterized by its scientific, rational, and effective utilization of two dynamic automatic control systems: the closed-loop dynamic control system for external air intake and the closed-loop dynamic control system for excess air coefficient. The system is simple, reliable, stable, efficient, and easy to debug, making it suitable for achieving fully automatic dynamic control of waste-to-energy incineration boilers.

[0088] Compared with existing technologies, the dynamic control method for the asymmetric characteristics of waste-to-energy incineration boilers and their flue gas pipelines has broken through technical bottlenecks, opening up a new and broad vision and space for waste-to-energy incineration boilers to achieve deep energy conservation and emission reduction, as well as increased production and quality. It has outstanding substantive features and significant progress, and its beneficial characteristics are:

[0089] (a) The theory of asymmetric system of waste incineration power generation boiler was proposed for the first time, laying a theoretical foundation for breaking through the technical bottleneck that has long plagued the control of waste incineration power generation boiler;

[0090] (b) A dynamic control method for the asymmetric system of waste incineration power generation boilers was proposed for the first time, which makes the amount of external air entering the waste incineration power generation boiler controllable and the excess air coefficient controllable;

[0091] (c) A mathematical model for calculating the amount of external air entering a waste-to-energy boiler and a closed-loop dynamic control technology for the amount of external air entering a waste-to-energy boiler were developed.

[0092] (d) A mathematical model for calculating the excess air coefficient of a waste-to-energy incineration boiler and a closed-loop dynamic control technology for the excess air coefficient of a waste-to-energy incineration boiler were developed.

[0093] (e) Effective and stable control of furnace pressure in the asymmetric system of waste incineration power generation boiler and fully automatic control of waste incineration power generation boiler have been achieved;

[0094] (f) By realizing dynamic control of external air intake and excess air coefficient, gas consumption is saved, heat loss of waste incineration power generation boiler is reduced, NOx and VOC emissions are reduced, and thermal efficiency of waste incineration power generation boiler is improved.

[0095] (g) Because the process is fully automated, the labor intensity of operators is reduced and the production rate is improved;

[0096] (h) Significant improvements in the characteristics of the fan duct network have enabled the induced draft fan to achieve deep energy savings;

[0097] (i) The controllable amount of external air entering and the controllable excess air coefficient enable the emission of pollutants from the flue gas of waste incineration power generation boilers, which are part of the furnace, to be fundamentally controlled. This can fundamentally solve the smog problem and is of great significance to the country's air pollution control.

[0098] The dynamic control method for asymmetric characteristics of waste-to-energy incineration boilers and their flue gas pipelines can be widely applied to newly built, expanded, and renovated waste-to-energy incineration boiler systems. The technical solution described herein is merely an example of one application area of ​​the invention and is not intended to limit the invention. Although the invention has been described in detail with reference to the example, those skilled in the art can still modify the technical solutions described in the example or make equivalent substitutions for some of the technical features. All modifications, equivalent substitutions, and improvements made within the control principles and control strategies of the invention should be included within the scope of protection of the invention.

Claims

1. A dynamic control method for the asymmetric characteristics of a waste-to-energy incineration boiler and its flue gas pipeline network, characterized in that... Based on the operating characteristics of waste-to-energy incineration boilers and the physical properties of their flue gas pipelines, an asymmetric system theory for waste-to-energy incineration boilers was established. Mathematical models for calculating the external air intake and excess air coefficient of waste-to-energy incineration boilers were developed. A dynamic control method for the external air intake and excess air coefficient based on this asymmetric system theory was also developed. The external air intake is calculated using argon content detected by flue gas analysis. Then, the opening of the induced draft fan inlet valve is adjusted based on the difference between the set value and the calculated value, forming a closed-loop dynamic adjustment system for the external air intake, ensuring that the external air intake is always controlled within the set value range. Similarly, the excess air coefficient is controlled by adjusting the secondary and primary air fan volumes based on oxygen and carbon monoxide content detected by flue gas analysis, forming a closed-loop dynamic adjustment system for the excess air coefficient, ensuring that the excess air coefficient is always controlled within the set value range. Equation (1) is a mathematical model for calculating the amount of external air entering a waste-to-energy boiler; Qair=(Qw×Arw-(Qf+Qs)×Arb)×22.4×100 / 0.934 (1) In the formula: Qf: Air flow rate of the primary air fan, m3 / s; Qs: Air flow rate of the secondary air fan, m3 / s; Arb: Mole fraction of argon in air, in mol% Qw: Flue gas flow rate, m3 / s; Arw: Mole fraction of argon in flue gas, mol% Qair: The amount of air entering the waste-to-energy boiler from the outside, in m3 / s; Equation (2) is a mathematical model for calculating the oxygen content in the external air intake of a waste incineration power generation boiler; O2e=(Qw×Arw-(Qf+Qs)×Arb)×20.95 / 0.934 (2) In the formula: Qf: Air flow rate of the primary air fan, m3 / s; Qs: Air flow rate of the secondary air fan, m3 / s; Arb: Mole fraction of argon in air, in mol% Qw: Flue gas flow rate, m3 / s; Arw: Mole fraction of argon in flue gas, mol% O2e: The amount of oxygen in the external air entering the waste-to-energy boiler, in moles; The actual oxygen content in the excess air coefficient is calculated using the mathematical model for calculating the oxygen content in the excess air coefficient, as shown in equation (3). O2a=(Qw×O21-kO2e) / Qw (3) In the formula: O2a: Actual oxygen content in the excess air coefficient, % Qw: Flue gas flow rate, m3 / s; O21: Mole fraction of oxygen in flue gas, mol% O2e: The amount of oxygen in the external air entering the waste-to-energy boiler, in moles; k: Proportion coefficient, 0~1; Substituting equation (3) into the simplified mathematical model for calculating the excess air coefficient (4), we obtain equation (5) for calculating the excess air coefficient. α=20.95 / (20.95-O2a) (4) In the formula: O2a: Actual oxygen content in the excess air coefficient, % α: Excess air coefficient, >0; The actual value of the excess air coefficient is calculated using the mathematical model for calculating the excess air coefficient, as shown in equation (5): α=20.95 / (20.95-(Qw×O21-kO2e) / Qw) (5) In the formula: Qw: Flue gas flow rate, m3 / s; O21: Mole fraction of oxygen in flue gas, mol% O2e: The amount of oxygen in the external air entering the waste-to-energy boiler, in moles; k: Proportion coefficient, 0~1; α: Excess air coefficient, >0.

2. The method according to claim 1, characterized in that... The technical solution of this method is as follows: The HMI operation station (1) of the waste incineration power generation boiler control system is the human-machine interface of the dynamic control system for the asymmetric characteristics of the waste incineration power generation boiler and its flue gas pipeline network; the external air inlet setting value (2) is connected to the HMI operation station (1) of the waste incineration power generation boiler control system and the induced draft fan inlet valve opening adjustment (3), and the setting value is input by the human-machine interface; the induced draft fan inlet valve opening adjustment (3) is connected to the external air inlet setting value (2), the mathematical model for calculating the external air inlet of the waste incineration power generation boiler (4), and the on-site process equipment (23) of the waste incineration power generation boiler, and the difference between the external air inlet setting value (2) and the mathematical model for calculating the external air inlet of the waste incineration power generation boiler (4) is used to adjust the opening of the induced draft fan inlet valve, control the flue gas flow through the inlet valve, suppress the entry of external air, and make the waste incineration power generation boiler more efficient. The amount of external air entering the waste incineration power plant is controlled within the set value range; the mathematical model (4) for calculating the amount of external air entering the waste incineration power plant is connected to the detection of Ar content in flue gas (5), flue gas flow rate (6), primary fan air volume (7), secondary fan air volume (8), mathematical model (10) for calculating the excess air coefficient of the waste incineration power plant, and the induced draft fan inlet valve opening adjustment (3). The amount of external air entering the waste incineration power plant is calculated based on the Ar content in flue gas, flue gas flow rate, primary fan air volume, and secondary fan air volume. The calculation results are sent to the induced draft fan inlet valve opening adjustment (3) and the mathematical model (10) for calculating the excess air coefficient of the waste incineration power plant; the detection of Ar content in flue gas (5) is connected to the mathematical model (4) for calculating the amount of external air entering the waste incineration power plant and the on-site process equipment (23) of the waste incineration power plant; The flue gas flow detection (6) is connected to the mathematical model (4) for calculating the external air intake of the waste incineration power plant and the on-site process equipment (23) of the waste incineration power plant; the primary air fan flow detection (7) is connected to the mathematical model (4) for calculating the external air intake of the waste incineration power plant and the on-site process equipment (23) of the waste incineration power plant; the secondary air fan flow detection (8) is connected to the mathematical model (4) for calculating the external air intake of the waste incineration power plant and the on-site process equipment (23) of the waste incineration power plant; the proportion coefficient k input (9) is connected to the HMI operation station (1) of the waste incineration power plant control system and the mathematical model for calculating the excess air coefficient of the waste incineration power plant. 10) Connected; The mathematical model for calculating the excess air coefficient of the waste incineration power generation boiler (10) is connected with the mathematical model for calculating the external air intake of the waste incineration power generation boiler (4), the excess air coefficient setpoint (11), the detection of O2 in the flue gas (12), and the secondary air fan air volume adjustment (13). Based on the mathematical model for calculating the external air intake of the waste incineration power generation boiler, the mathematical model for calculating the excess air coefficient of the waste incineration power generation boiler is derived. The difference between the excess air coefficient setpoint and the calculated value of the excess air coefficient of the waste incineration power generation boiler is used to adjust the air volume of the secondary air fan and dynamically control the excess air coefficient of the waste incineration power generation boiler. The excess air coefficient setpoint (11) is set as the set value of the waste incineration power generation boiler. The set value is input from the human-machine interface of the HMI operation station (1) of the waste-to-energy boiler control system; the O2 content detection (12) in the flue gas is the actual value of O2 content, which is used as a feedback value to participate in the calculation of the excess air coefficient; the secondary air fan air volume adjustment (13) is the controlled variable, and the difference in the excess air coefficient calculation is used to adjust the secondary air fan air volume to adjust the excess air coefficient; the air-fuel ratio (14) is input from the human-machine interface of the HMI operation station (1) of the waste-to-energy boiler control system; the furnace temperature set value (15) is the set value, which is input from the human-machine interface of the HMI operation station (1) of the waste-to-energy boiler control system; the actual value of the furnace temperature (16) is the furnace temperature control feedback value; the primary The blower air volume adjustment (17) is the controlled variable. The primary blower air volume is adjusted according to the difference between the furnace temperature set value and the actual furnace temperature to dynamically control the furnace temperature. The CO set value (18) of the waste incineration power generation boiler is the set value, which is input by the human-machine interface of the waste incineration power generation boiler control system HMI operation station (1). The actual CO value in the flue gas (19) is the actual CO detection value, which is compared with the CO set value (18) of the waste incineration power generation boiler as negative feedback. The difference is used to adjust the primary blower air volume to improve the combustion condition. The furnace pressure set value (20) is the set value, which is input by the human-machine interface of the waste incineration power generation boiler control system HMI operation station (1).The induced draft fan airflow regulation (21) is connected to the furnace pressure setpoint (20), the actual furnace pressure (22), and the on-site process equipment (23) of the waste incineration power generation boiler. It adjusts the induced draft fan airflow based on the feedback difference between the furnace pressure setpoint and the actual furnace pressure, thus dynamically controlling the furnace pressure. The on-site process equipment (23) of the waste incineration power generation boiler is an online device for the waste incineration power generation boiler.

3. The method according to claim 1, characterized in that... The amount of external air entering the waste-to-energy boiler is calculated by detecting inert gases in the flue gas.

4. The method according to claim 1, characterized in that... In practical engineering applications, the set values ​​for external air intake, excess air coefficient, and CO of the waste-to-energy boiler are set respectively. These set values ​​are determined by the waste-to-energy boiler process engineer based on the specific operating conditions of the waste-to-energy boiler and are input into the HMI operator station of the control system.

5. The method according to claim 1, characterized in that... Slight negative pressure control is adopted for waste incineration power generation boilers.

6. The method according to claim 1, characterized in that... In equation (3), k is the percentage of oxygen remaining when the amount of oxygen entering the external air reaches the flue gas detection point, that is, the proportion of the remaining oxygen to the amount of oxygen entering the external air, referred to as the proportion coefficient, which ranges from 0 to 1. The proportion coefficient k is determined by the waste incineration power generation boiler process engineer based on the detection statistics of the amount of external air entering the power generation boiler body and the amount of air leakage in the flue gas pipeline network, and is input in the HMI operation station.

7. The method according to claim 1, characterized in that... Regarding the external air intake of the waste-to-energy incineration boiler, the pipeline leakage can be determined experimentally during system commissioning or equipment maintenance. Specifically, the dynamic control system for external air intake is adjusted to bring the boiler furnace pressure to zero. The argon content measured by flue gas analysis is used to calculate the external air intake. This calculated external air intake is the pipeline leakage. The pipeline leakage calculation result is displayed on the HMI (Human-Machine Interface) station. The pipeline leakage is used for excess air coefficient calculation and equipment maintenance guidance. If the calculated pipeline leakage is too high, equipment maintenance should be organized as soon as possible.

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