A high-alkali coal blending combustion anti-furnace coking regulation system

Abstract

The present application is suitable for the field of anti-coking technology of coal-fired boiler, and provides a high-alkali coal blending combustion anti-chamber coking regulation and control system, which comprises a coal quality adaptive blending module with a built-in high-alkali coal coking tendency quantification model, a combustion condition synergistic regulation and control module, and a coking situation linkage prevention and control module; the output end of the coal quality adaptive blending module is in communication connection with the input end of the combustion condition synergistic regulation and control module; the combustion condition synergistic regulation and control module and the coking situation linkage prevention and control module are in bidirectional data interaction; and the feedback end of the coking situation linkage prevention and control module is electrically connected with the control ends of the coal quality adaptive blending module and the combustion condition synergistic regulation and control module respectively; the present application realizes the source precise control of the high-alkali coal coking tendency, the process closed-loop optimization of the blending combustion condition, and the end staged prevention and control of the coking situation in sequence, forms a "source-process-end" whole-chain anti-coking regulation and control closed loop, and effectively solves the industry problem that the existing coal blending combustion and coking prevention and control are disconnected.

Description

Technical Field

[0001] This invention belongs to the field of anti-coking technology for coal-fired boilers, and particularly relates to a control system for preventing coking in the furnace by blending high-alkali coal. Background Technology

[0002] High-alkali coal generally has the typical characteristics of high sodium, high calcium, and low ash melting temperature. During combustion, it is extremely prone to causing severe coking on the water-cooled walls of the furnace, which is the core problem restricting the safe and efficient utilization of this type of coal. Coal blending is currently the mainstream technical means to prevent coking of high-alkali coal, but existing technologies still have the following core defects in practical applications:

[0003] The existing high-alkali coal blending and combustion mostly adopts a fixed-ratio static blending mode, without dynamically adapting to the real-time characteristics and coking tendency of the coal entering the furnace. This makes it impossible to cope with the changes in coking risk caused by coal quality fluctuations, and the accuracy of source coking prevention and control is seriously insufficient.

[0004] The coal blending and combustion system is independent of the boiler combustion control system. The changes in coal quality characteristics after blending cannot synchronously drive the dynamic optimization of combustion parameters, which can easily lead to local high temperature in the furnace and enrichment of reducing atmosphere, further reducing the ash melting temperature and exacerbating the risk of coking.

[0005] The lack of a linkage mechanism between the coal blending and combustion system and the furnace coking prevention and control equipment makes it impossible to achieve graded prevention and control based on the coking status of the furnace after blending. This can easily lead to the coking developing from localized loose deposits into large-area hardened coke lumps, making it impossible to form a closed loop for the entire chain of coking prevention and control.

[0006] Therefore, a high-alkali coal blending and coking prevention control system is needed to solve the above problems. Summary of the Invention

[0007] The purpose of this invention is to provide a high-alkali coal blending and coking prevention control system to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A high-alkali coal blending and coking prevention control system includes a coal quality matching module with a built-in quantitative model of high-alkali coal coking tendency, a combustion condition collaborative control module, and a coking situation linkage prevention and control module.

[0010] The output end of the coal quality matching and blending module is communicatively connected to the input end of the combustion condition coordinating control module, and is used to output the coal blending scheme and coal quality characteristic parameters to the combustion condition coordinating control module.

[0011] The signal output terminal of the combustion condition coordinated control module is communicatively connected to the signal input terminal of the coking situation linkage prevention and control module, and the feedback control terminal of the coking situation linkage prevention and control module is electrically connected to the execution terminal of the coal quality matching and blending module and the combustion condition coordinated control module, respectively.

[0012] The coal quality matching and blending module, the combustion condition collaborative control module, and the coking situation linkage prevention and control module are all bidirectionally connected to the boiler DCS system.

[0013] A further technical solution is that the coal quality matching and blending module includes an online coal quality detection unit, a coking tendency calculation unit, a coal blending ratio optimization unit, and a coal blending execution unit;

[0014] The output of the online coal quality detection unit is electrically connected to the input of the coking tendency calculation unit, the output of the coking tendency calculation unit is communicatively connected to the input of the coal blending ratio optimization unit, and the output of the coal blending ratio optimization unit is electrically connected to the control end of the coal blending execution unit.

[0015] The effect is as follows: Through real-time coal quality monitoring, quantification of coking tendency, optimization of coal blending scheme, and full-process control of coal blending execution, dynamic and precise matching of the proportion of high-alkali coal blending is achieved, reducing the coking risk of coal entering the furnace from the source.

[0016] In a further technical solution, the online coal quality detection unit includes an industrial analysis and detection subunit, an ash fusion characteristic detection subunit, and an alkali metal content detection subunit. The signal output terminals of the industrial analysis and detection subunit, the ash fusion characteristic detection subunit, and the alkali metal content detection subunit are all electrically connected to the input terminal of the coking tendency calculation unit.

[0017] The results are as follows: Through simultaneous online detection of multi-dimensional coal quality parameters, the core influencing indicators of coking in high-alkali coal are fully captured, providing accurate basic data support for coking tendency calculation and coal blending scheme optimization.

[0018] In a further technical solution, the coal blending execution unit includes multiple sets of coal feeder frequency conversion control subunits and blending ratio verification subunits. The signal input terminal of the coal feeder frequency conversion control subunit is electrically connected to the coal blending ratio optimization unit, and the signal output terminal of the blending ratio verification subunit is bidirectionally connected to the feedback terminal of the coal blending ratio optimization unit.

[0019] The effect is that the feed rate of different coal types can be accurately adjusted through frequency conversion control, and the actual blending ratio of coal entering the furnace can be verified and corrected in real time to ensure the accurate implementation of the coal blending plan.

[0020] A further technical solution is that the combustion condition coordinated control module includes an air distribution parameter adjustment unit, a burner tilt control unit, a furnace temperature field optimization unit, and a reducing atmosphere suppression unit;

[0021] The signal input terminals of the air distribution parameter adjustment unit and the burner swing angle control unit are both communicatively connected to the output terminal of the coal quality matching and blending module. The output terminals of the air distribution parameter adjustment unit and the burner swing angle control unit are electrically connected to the input terminals of the furnace temperature field optimization unit and the reducing atmosphere suppression unit, respectively.

[0022] The effect is as follows: based on the changes in coal quality characteristics after co-firing, combustion parameters such as air distribution and burner tilt angle are optimized simultaneously to achieve uniform distribution of furnace temperature field and effective suppression of reducing atmosphere, thereby eliminating the inducing conditions for coking during combustion.

[0023] In a further technical solution, the air distribution parameter adjustment unit includes a secondary air stratification control subunit and an excess air coefficient closed-loop adjustment subunit. The execution ends of the secondary air stratification control subunit and the excess air coefficient closed-loop adjustment subunit are electrically connected to the boiler secondary air system, and the signal feedback ends are bidirectionally connected to the reducing atmosphere suppression unit.

[0024] The effect is as follows: through precise control of secondary air stratification and closed-loop adjustment of excess air coefficient, the dynamic balance of air-coal ratio is ensured, avoiding the formation of a reducing atmosphere by local oxygen deficiency combustion, while optimizing the aerodynamic field inside the furnace to prevent flame from sticking to the wall and causing local high temperature.

[0025] A further technical solution is that the coking situation linkage prevention and control module includes a furnace thermal parameter acquisition unit, a coking situation classification and judgment unit, a classification prevention and control execution unit, and a control effect feedback unit.

[0026] The output of the furnace thermal parameter acquisition unit is electrically connected to the input of the coking status classification and determination unit, the output of the coking status classification and determination unit is communicatively connected to the control end of the classification and control execution unit, and the output of the classification and control execution unit is electrically connected to the input of the control effect feedback unit.

[0027] The effect is as follows: through a complete chain of real-time acquisition of furnace thermal parameters, graded judgment of coking status, graded prevention and control execution, and effect feedback, the coking status of the furnace after coking is perceived in real time and precisely controlled, thus curbing the continuous spread of coking.

[0028] A further technical solution is that the furnace thermal parameter acquisition unit includes an array-type heat flux density acquisition subunit, a furnace flue gas composition acquisition subunit, and a water-cooled wall temperature acquisition subunit. The detection ends of the three are all arranged in the boiler furnace water-cooled wall and combustion area, and the signal output ends are all electrically connected to the coking status grading and determination unit.

[0029] The effect is that by deploying a multi-type sensor array, the coking-related parameters such as furnace water-cooled wall heat flux density, flue gas composition, and wall temperature can be collected across the entire range, providing a comprehensive and real-time data source for the classification and determination of coking status.

[0030] In a further technical solution, the graded prevention and control execution unit includes an acoustic soot blowing control subunit, a soot blower timing control subunit, and an emergency combustion adjustment subunit. The control input terminals of the three are all electrically connected to the coking status graded judgment unit, and the execution terminals are all communicatively connected to the corresponding anti-coking equipment of the boiler.

[0031] The effect is that, based on different levels of coking conditions, differentiated prevention and control strategies are implemented to achieve preventive cleaning of light coking, precise removal of moderate coking, and emergency intervention for severe coking, while taking into account both prevention and control effectiveness and equipment operation economy.

[0032] In a further technical solution, the signal output terminal of the control effect feedback unit is bidirectionally connected to the coal blending ratio optimization unit of the coal quality matching coal blending module and the air distribution parameter adjustment unit of the combustion condition collaborative control module, forming a closed-loop control link.

[0033] The effect is to provide real-time feedback on the coking prevention and control effect to the source coal blending and process combustion control links, realize continuous iterative optimization of coal blending schemes and combustion parameters, and build a closed-loop control system for coking prevention and control across the entire chain of "source-process-end".

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] This invention, through a coal quality matching and blending module, incorporates a quantitative model for the coking tendency of high-alkali coal, enabling real-time quantification of the coking tendency of high-alkali coal and dynamic optimization of the blending ratio. This replaces the traditional fixed-ratio static blending mode, accurately responding to fluctuations in the quality of coal entering the furnace and stably controlling the softening temperature of the mixed coal ash above 1350℃, thus significantly reducing the risk of coking from the source.

[0036] This invention establishes a coordinated linkage mechanism between coal blending and combustion parameters through a combustion condition coordinated control module. Based on the coal quality characteristics after blending, combustion parameters such as air distribution and flame center are optimized simultaneously, which can effectively eliminate local high temperature and reducing atmosphere in the furnace, avoid the imbalance of combustion conditions from aggravating coking, and eliminate the coking-inducing conditions in the process.

[0037] This invention constructs a hierarchical linkage system between coal blending and coking prevention equipment through a coking status linkage prevention and control module. It implements differentiated prevention and control strategies based on the coking status level and feeds back the prevention and control effect to the front-end module, forming a closed-loop management and control system that can effectively curb the spread of coking and achieve full-process prevention and control of coking in high-alkali coal.

[0038] To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the overall architecture of the present invention;

[0040] Figure 2 This is a schematic diagram of the internal unit architecture and data flow of the coal quality adaptation and blending module of the present invention;

[0041] Figure 3 This is a schematic diagram showing the subunit composition and core parameter output of the online coal quality detection unit of the present invention;

[0042] Figure 4 This is a schematic diagram of the internal sub-unit architecture and control execution link of the coal blending execution unit of the present invention;

[0043] Figure 5 This is a schematic diagram of the internal unit architecture and collaborative control logic of the combustion condition collaborative control module of the present invention;

[0044] Figure 6 This is a schematic diagram of the sub-unit architecture and control execution of the air distribution parameter adjustment unit of the present invention;

[0045] Figure 7 This is a schematic diagram of the overall architecture and closed-loop feedback link of the coking situation linkage prevention and control module of the present invention;

[0046] Figure 8 This is a schematic diagram of the subunit composition and data output of the furnace thermal parameter acquisition unit of the present invention;

[0047] Figure 9 This is a schematic diagram illustrating the corresponding logic of the graded determination and graded prevention and control of coking status in this invention;

[0048] Figure 10 This is a schematic diagram illustrating the entire working principle of the present invention.

[0049] In the diagram: 1. Coal quality matching and blending module; 11. Online coal quality detection unit; 111. Industrial analysis and testing subunit; 112. Ash fusion characteristic detection subunit; 113. Alkali metal content detection subunit; 12. Coking tendency calculation unit; 13. Coal blending ratio optimization unit; 14. Coal blending execution unit; 141. Coal feeder frequency conversion control subunit; 142. Blending ratio verification subunit; 2. Combustion condition coordinated control module; 21. Air distribution parameter adjustment unit; 211. Secondary air stratification control subunit; 212. Excess air coefficient closed-loop adjustment subunit; 2 2. Burner tilt control unit; 23. Furnace temperature field optimization unit; 24. Reducing atmosphere suppression unit; 3. Coking situation linkage prevention and control module; 31. Furnace thermal parameter acquisition unit; 311. Array-type heat flux density acquisition subunit; 312. Furnace flue gas composition acquisition subunit; 313. Water-cooled wall temperature acquisition subunit; 32. Coking situation classification judgment unit; 33. Classification prevention and control execution unit; 331. Acoustic soot blowing control subunit; 332. Soot blower timing control subunit; 333. Emergency combustion adjustment subunit; 34. Control effect feedback unit. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0051] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0052] like Figure 1-10 As shown, this embodiment of the invention provides a high-alkali coal blending and coking prevention control system, including a coal quality matching and blending module 1 with a built-in quantitative model of high-alkali coal coking tendency, a combustion condition collaborative control module 2, and a coking situation linkage prevention and control module 3.

[0053] In this embodiment, the coal quality matching and blending module 1, the combustion condition coordination and control module 2, and the coking situation linkage and prevention and control module 3 are all deployed on the power plant's industrial control server. They establish a two-way communication connection with the boiler DCS system through industrial Ethernet. The modules interact with each other and transmit commands through the Profibus-DP industrial bus. The entire system starts and stops synchronously with the boiler, adapting to the boiler's 20%-100% full load operating requirements.

[0054] Specifically, the coal quality matching and blending module 1 includes an online coal quality detection unit 11, a coking tendency calculation unit 12, a coal blending ratio optimization unit 13, and a coal blending execution unit 14. The output end of the online coal quality detection unit 11 is electrically connected to the input end of the coking tendency calculation unit 12 via a shielded cable. The output end of the coking tendency calculation unit 12 is communicatively connected to the input end of the coal blending ratio optimization unit 13 via an industrial switch. The output end of the coal blending ratio optimization unit 13 is electrically connected to the control end of the coal blending execution unit 14 via a PLC controller.

[0055] In this embodiment, the sampling end of the online coal quality detection unit 11 is arranged at the sampling port of the coal conveyor belt and the raw coal bunker, which can realize the real-time online detection of coal quality parameters entering the furnace. The detection data is synchronously transmitted to the coking tendency calculation unit 12. The coking tendency calculation unit 12 has a built-in quantitative model of coking tendency of high-alkali coal, which can output the quantitative value of coking risk based on coal quality parameters. The coal blending ratio optimization unit 13 generates the optimal blending ratio scheme of multiple coal types based on the coking risk value and the boiler design coal type parameters. The coal blending execution unit 14 accurately executes the coal blending scheme to realize the source control of coking risk of coal entering the furnace.

[0056] Specifically, the online coal quality detection unit 11 includes an industrial analysis and detection subunit 111, an ash fusion characteristic detection subunit 112, and an alkali metal content detection subunit 113. The signal output terminals of the industrial analysis and detection subunit 111, the ash fusion characteristic detection subunit 112, and the alkali metal content detection subunit 113 are all electrically connected to the input terminal of the coking tendency calculation unit 12.

[0057] In this embodiment, the industrial analysis and detection subunit 111 is used to detect industrial analysis parameters such as moisture, ash, volatile matter, and fixed carbon in coal; the ash fusion characteristic detection subunit 112 is used to detect the deformation temperature DT, softening temperature ST, and flow temperature FT of coal; and the alkali metal content detection subunit 113 is used to detect the content of alkali metal oxides such as Na2O and CaO in coal. These three types of parameters together constitute the core input indicators for calculating the coking tendency of high-alkali coal, ensuring the comprehensiveness of coal quality characteristic detection.

[0058] Specifically, the coal blending execution unit 14 includes multiple sets of coal feeder frequency conversion control subunits 141 and blending ratio verification subunits 142. The signal input terminal of the coal feeder frequency conversion control subunit 141 is electrically connected to the coal blending ratio optimization unit 13, and the signal output terminal of the blending ratio verification subunit 142 is bidirectionally connected to the feedback terminal of the coal blending ratio optimization unit 13.

[0059] In this embodiment, the coal feeder frequency conversion control subunit 141 corresponds one-to-one with the coal feeders corresponding to each raw coal bunker of the boiler. It can accurately adjust the coal feeding frequency and coal feeding amount of each coal feeder according to the coal blending plan. The blending ratio verification subunit 142 verifies the deviation between the actual blending ratio and the design plan in real time through online detection data of coal entering the furnace, and feeds back the deviation data to the coal blending ratio optimization unit 13 to realize the dynamic correction of the coal blending plan and ensure the accuracy of the blending ratio.

[0060] Specifically, the combustion condition coordinated control module 2 includes an air distribution parameter adjustment unit 21, a burner tilt control unit 22, a furnace temperature field optimization unit 23, and a reducing atmosphere suppression unit 24. The signal input terminals of the air distribution parameter adjustment unit 21 and the burner tilt control unit 22 are both communicatively connected to the output terminal of the coal quality matching and blending module 1, and the output terminals of the air distribution parameter adjustment unit 21 and the burner tilt control unit 22 are electrically connected to the input terminals of the furnace temperature field optimization unit 23 and the reducing atmosphere suppression unit 24, respectively.

[0061] In this embodiment, the air distribution parameter adjustment unit 21 is electrically connected to the actuator of the boiler secondary air system, and the burner tilt control unit 22 is driven by the tilt drive motor of the boiler burner. Based on the coal quality characteristic parameters transmitted by the coal quality matching and blending module 1, the two synchronously optimize the air distribution parameters and the burner tilt angle. The furnace temperature field optimization unit 23 and the reducing atmosphere suppression unit 24 perform real-time verification of the control effect based on the real-time operating data of the boiler DCS system, continuously optimize the combustion parameters, and ensure the accurate matching of furnace combustion conditions and blended coal quality characteristics.

[0062] Specifically, the air distribution parameter adjustment unit 21 includes a secondary air stratification control subunit 211 and an excess air coefficient closed-loop adjustment subunit 212. The execution ends of the secondary air stratification control subunit 211 and the excess air coefficient closed-loop adjustment subunit 212 are both electrically connected to the boiler secondary air system, and the signal feedback ends are both bidirectionally connected to the reducing atmosphere suppression unit 24.

[0063] In this embodiment, the secondary air stratification control subunit 211 can independently adjust the opening of the secondary air dampers of each layer of the boiler to optimize the aerodynamic field inside the furnace. The excess air coefficient closed-loop adjustment subunit 212 dynamically adjusts the total air volume based on the real-time data of oxygen at the furnace outlet to ensure that the excess air coefficient in the furnace is stable within a reasonable range. The two work together to avoid the formation of a reducing atmosphere due to local oxygen deficiency during combustion, while also preventing the flame center from shifting upward due to excessive air volume.

[0064] Specifically, the coking situation linkage prevention and control module 3 includes a furnace thermal parameter acquisition unit 31, a coking situation classification and judgment unit 32, a classification and control execution unit 33, and a control effect feedback unit 34; the output end of the furnace thermal parameter acquisition unit 31 is electrically connected to the input end of the coking situation classification and judgment unit 32, the output end of the coking situation classification and judgment unit 32 is communicatively connected to the control end of the classification and control execution unit 33, and the output end of the classification and control execution unit 33 is electrically connected to the input end of the control effect feedback unit 34.

[0065] In this embodiment, the sensor array of the furnace thermal parameter acquisition unit 31 is arranged on the fire-facing side of the boiler furnace water-cooled wall, and layered along the furnace height and circumference. This enables real-time acquisition of coking-related parameters throughout the furnace. The coking status grading and determination unit 32 has a built-in coking level determination standard, which can complete the grading and determination of the coking status based on the acquired data. The graded prevention and control execution unit 33 executes the corresponding prevention and control strategy based on the coking level. The control effect feedback unit 34 collects the prevention and control effect data in real time to achieve closed-loop feedback optimization.

[0066] Specifically, the furnace thermal parameter acquisition unit 31 includes an array-type heat flux density acquisition subunit 311, a furnace flue gas composition acquisition subunit 312, and a water-cooled wall temperature acquisition subunit 313. The detection ends of the three are all arranged in the boiler furnace water-cooled wall and combustion area, and the signal output ends are all electrically connected to the coking status classification and determination unit 32.

[0067] In this embodiment, the array-type heat flux density acquisition subunit 311 consists of 30 sets of high-precision heat flux density sensors, which are arranged in a matrix along the circumference and height of the furnace water-cooled wall. The furnace flue gas composition acquisition subunit 312 consists of multiple sets of in-situ laser gas analyzers, which are arranged in the furnace combustion zone and near-wall zone. The water-cooled wall temperature acquisition subunit 313 consists of multiple sets of armored thermocouples, which are arranged in close contact with the water-cooled wall surface. The three types of acquisition devices work together to provide real-time data in all dimensions for determining the coking situation.

[0068] Specifically, the graded prevention and control execution unit 33 includes an acoustic soot blowing control subunit 331, a soot blower timing control subunit 332, and an emergency combustion adjustment subunit 333. The control input terminals of all three are electrically connected to the coking status graded judgment unit 32, and the execution terminals are communicatively connected to the corresponding anti-coking equipment of the boiler.

[0069] In this embodiment, the acoustic soot blowing control subunit 331 is electrically connected to the acoustic ash remover installed in the furnace for preventive cleaning of light coking. The soot blower timing control subunit 332 is electrically connected to the actuator of the boiler steam soot blowing system for targeted and precise removal of moderate coking. The emergency combustion adjustment subunit 333 is communicatively connected to the boiler combustion control system for emergency intervention of severe coking. Through a graded prevention and control strategy, both the anti-coking effect and the economic efficiency of equipment operation are taken into account.

[0070] Specifically, the signal output terminal of the control effect feedback unit 34 is bidirectionally connected to the coal blending ratio optimization unit 13 of the coal quality matching coal blending module 1 and the air distribution parameter adjustment unit 21 of the combustion condition collaborative control module 2, forming a closed-loop control link.

[0071] In this embodiment, the control effect feedback unit 34 feeds back the data on the furnace coking status and thermal parameter changes after control to the coal quality matching and blending module 1 and the combustion condition collaborative control module 2 in real time. The two modules continuously optimize the coal blending scheme and combustion parameters based on the feedback data, realize the adaptive iterative optimization of the whole system, and build a closed-loop control system for anti-coking that covers the entire chain from the source to the process to the end.

[0072] The circuits, electronic components, modules, and control algorithms involved in this embodiment are all existing technologies, which can be fully implemented by those skilled in the art, and need not be elaborated upon. The content protected by this invention does not involve any improvement to the software and methods.

[0073] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0074] Working principle and usage process of this invention:

[0075] The high-alkali coal blending and coking prevention control system of the present invention follows a three-stage progressive control logic of "source adaptation - process coordination - end-point control - closed-loop feedback". The core workflow is as follows:

[0076] Phase 1: Source Coal Quality Adaptation and Control: After system startup, the online coal quality detection unit 11 of the coal quality adaptation and blending module 1 collects the core parameters of high-alkali coal and blended coal types entering the furnace in real time. Among them, the industrial analysis detection subunit 111 detects industrial analysis parameters such as moisture, ash, volatile matter, and fixed carbon of the coal; the ash fusion characteristic detection subunit 112 detects the deformation temperature DT, softening temperature ST, and flow temperature FT of the coal; and the alkali metal content detection subunit 113 detects the content of alkali metal oxides such as Na2O and CaO in the coal. All detection data are synchronously transmitted to the coking tendency calculation unit 12. Combining the coking tendency quantitative model of high-alkali coal built into the coal quality matching and blending module 1, the coking risk level of the coal fed into the furnace is quantitatively calculated; based on the coking tendency calculation results, the coal blending ratio optimization unit 13 generates an optimal coal blending scheme for multiple coal types with ash softening temperature ≥1350℃ and Na2O content in ash ≤1% as the core control targets; the coal blending execution unit 14 accurately executes the coal blending scheme through the coal feeder frequency conversion control subunit 141, and the blending ratio verification subunit 142 verifies the actual blending ratio in real time and feeds it back to the coal blending ratio optimization unit 13 for dynamic correction, ensuring accurate control of coking risk at the source.

[0077] Phase Two: Coordinated Control of Combustion Conditions: The coal quality matching and blending module 1 transmits the real-time coal blending scheme and coal quality characteristic parameters to the coordinated control module 2 of combustion conditions. Based on the coal quality characteristics, the air distribution parameter adjustment unit 21 optimizes the secondary air ratio of each layer through the secondary air stratification control subunit 211, and the excess air coefficient closed-loop adjustment subunit 212 dynamically adjusts the excess air coefficient of the furnace to ensure a balanced air-coal ratio. The burner tilt control unit 22 synchronously adjusts the burner tilt angle to optimize the flame center position and prevent the flame from sticking to the wall. Based on the control results, the furnace temperature field optimization unit 23 and the reducing atmosphere suppression unit 24 monitor the furnace temperature field distribution and reducing gas concentration in real time, continuously optimize combustion parameters, ensure uniform furnace temperature distribution, and maintain the oxygen concentration in the near-wall area above 3%, thereby eliminating the inducing conditions for coking during combustion.

[0078] Phase 3: End-of-Stage Coking Status Linkage Prevention and Control and Closed-Loop Feedback: The furnace thermal parameter acquisition unit 31 of the coking status linkage prevention and control module 3, through the array-type heat flux density acquisition subunit 311, the furnace flue gas composition acquisition subunit 312, and the water-cooled wall temperature acquisition subunit 313, collects parameters such as furnace water-cooled wall heat flux density, flue gas composition, and wall temperature in real time, and transmits them to the coking status classification judgment unit 32, which classifies the coking status into three levels: mild, moderate, and severe. The classification prevention and control execution unit 33 executes differentiated prevention and control strategies based on the coking status, and for mild coking... The coking process begins with the sonic soot blowing control subunit 331 for preventative cleaning. For moderate coking, the soot blowing timing control subunit 332 performs precise targeted soot blowing. For severe coking, the emergency combustion adjustment subunit 333 is triggered to simultaneously optimize combustion parameters. The control effect feedback unit 34 collects coking status data after prevention and control in real time and feeds it back to the coal blending ratio optimization unit 13 of the coal quality matching and blending module 1 and the air distribution parameter adjustment unit 21 of the combustion condition collaborative control module 2. This continuously optimizes the coal blending scheme and combustion parameters, forming a closed-loop control system covering the entire chain from source to process to end.

[0079] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-alkali coal blending and coking prevention control system for furnaces, characterized in that, It includes a coal quality matching and blending module (1) with a built-in quantitative model of coking tendency of high-alkali coal, a combustion condition coordinated control module (2) and a coking situation linkage prevention and control module (3). The output end of the coal quality matching and blending module (1) is connected to the input end of the combustion condition coordination and control module (2) for outputting the coal blending scheme and coal quality characteristic parameters to the combustion condition coordination and control module (2); The signal output terminal of the combustion condition coordinated control module (2) is communicatively connected to the signal input terminal of the coking situation linkage control module (3), and the feedback control terminal of the coking situation linkage control module (3) is electrically connected to the execution terminal of the coal quality matching and blending module (1) and the combustion condition coordinated control module (2), respectively. The coal quality matching and blending module (1), the combustion condition coordination and control module (2), and the coking situation linkage and prevention and control module (3) are all bidirectionally connected to the boiler DCS system.

2. The high-alkali coal blending and coking prevention control system according to claim 1, characterized in that, The coal quality matching and blending module (1) includes an online coal quality detection unit (11), a coking tendency calculation unit (12), a coal blending ratio optimization unit (13), and a coal blending execution unit (14). The output end of the online coal quality detection unit (11) is electrically connected to the input end of the coking tendency calculation unit (12), the output end of the coking tendency calculation unit (12) is communicatively connected to the input end of the coal blending ratio optimization unit (13), and the output end of the coal blending ratio optimization unit (13) is electrically connected to the control end of the coal blending execution unit (14).

3. The high-alkali coal blending and coking prevention control system according to claim 2, characterized in that, The online coal quality detection unit (11) includes an industrial analysis and detection subunit (111), an ash fusion characteristic detection subunit (112), and an alkali metal content detection subunit (113). The signal output terminals of the industrial analysis and detection subunit (111), the ash fusion characteristic detection subunit (112), and the alkali metal content detection subunit (113) are all electrically connected to the input terminal of the coking tendency calculation unit (12).

4. The high-alkali coal blending and coking prevention control system according to claim 2, characterized in that, The coal blending execution unit (14) includes multiple sets of coal feeder frequency conversion control subunits (141) and blending ratio verification subunits (142). The signal input terminal of the coal feeder frequency conversion control subunit (141) is electrically connected to the coal blending ratio optimization unit (13), and the signal output terminal of the blending ratio verification subunit (142) is bidirectionally connected to the feedback terminal of the coal blending ratio optimization unit (13).

5. The high-alkali coal blending and coking prevention control system according to claim 1, characterized in that, The combustion condition coordinated control module (2) includes an air distribution parameter adjustment unit (21), a burner tilt control unit (22), a furnace temperature field optimization unit (23), and a reducing atmosphere suppression unit (24). The signal input terminals of the air distribution parameter adjustment unit (21) and the burner swing angle control unit (22) are both connected to the output terminal of the coal quality matching and blending module (1). The output terminals of the air distribution parameter adjustment unit (21) and the burner swing angle control unit (22) are respectively connected to the input terminals of the furnace temperature field optimization unit (23) and the reducing atmosphere suppression unit (24).

6. The high-alkali coal blending and coking prevention control system according to claim 5, characterized in that, The air distribution parameter adjustment unit (21) includes a secondary air stratification control subunit (211) and an excess air coefficient closed-loop adjustment subunit (212). The execution ends of the secondary air stratification control subunit (211) and the excess air coefficient closed-loop adjustment subunit (212) are electrically connected to the boiler secondary air system, and the signal feedback ends are bidirectionally connected to the reducing atmosphere suppression unit (24).

7. The high-alkali coal blending and coking prevention control system according to claim 1, characterized in that, The coking situation linkage prevention and control module (3) includes a furnace thermal parameter acquisition unit (31), a coking situation classification judgment unit (32), a classification prevention and control execution unit (33), and a control effect feedback unit (34). The output end of the furnace thermal parameter acquisition unit (31) is electrically connected to the input end of the coking status classification judgment unit (32), the output end of the coking status classification judgment unit (32) is communicatively connected to the control end of the classification control execution unit (33), and the output end of the classification control execution unit (33) is electrically connected to the input end of the control effect feedback unit (34).

8. The high-alkali coal blending and coking prevention control system according to claim 7, characterized in that, The furnace thermal parameter acquisition unit (31) includes an array-type heat flux density acquisition subunit (311), a furnace flue gas component acquisition subunit (312), and a water-cooled wall temperature acquisition subunit (313). The detection ends of the three are all arranged in the boiler furnace water-cooled wall and combustion area, and the signal output ends are all electrically connected to the coking status classification and determination unit (32).

9. A high-alkali coal blending and coking prevention control system according to claim 7, characterized in that, The graded prevention and control execution unit (33) includes an acoustic soot blowing control subunit (331), a soot blower timing control subunit (332), and an emergency combustion adjustment subunit (333). The control input terminals of the three are all electrically connected to the coking status graded judgment unit (32), and the execution terminals are all communicatively connected to the corresponding anti-coking equipment of the boiler.

10. A high-alkali coal blending and coking prevention control system according to claim 7, characterized in that, The signal output terminal of the control effect feedback unit (34) is bidirectionally connected to the coal blending ratio optimization unit (13) of the coal quality matching coal blending module (1) and the air distribution parameter adjustment unit (21) of the combustion condition collaborative control module (2), forming a closed-loop control link.

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