A flue gas purification coupling collaborative control method, device and medium

Abstract

The present application belongs to the technical field of flue gas purification, and relates to a flue gas purification coupling and collaborative control method, equipment and medium, comprising: controlling the ammonia injection amount of an ammonia injection dilution fan according to an SCR ammonia injection amount control instruction; controlling the opening of a flue gas shunting three-way valve according to a flue gas shunting control instruction to adjust the flue gas proportion of a main flue entering an SCR reactor and a bypass flue provided with a heat exchange coil converging into a COAP purification inlet; controlling an SCR outlet clean flue gas shunting branch valve according to an escaped ammonia shunting control instruction to shunt the clean flue gas carrying escaped ammonia at the SCR outlet to a COAP adsorption bin as an auxiliary adsorption aid; controlling a COAP cooling temperature gear according to a COAP cooling temperature control instruction; controlling a COAP adsorbent regeneration period according to an adsorbent regeneration control instruction; and controlling a COAP desorption regeneration outlet backflow pipeline valve according to an acid gas backflow control instruction to backflow the acid gas generated by COAP desorption regeneration to the SCR front flue for secondary catalytic decomposition.

Description

Technical Field

[0001] This invention belongs to the field of flue gas purification technology, specifically relating to a flue gas purification coupled and coordinated control method, equipment and medium. Background Technology

[0002] When thermal power units participate in deep grid peak shaving, the unit load fluctuates frequently, causing significant fluctuations in flue gas temperature and pollutant concentration in the boiler tail flue. Selective catalytic reduction (SCR) and low-temperature adsorption purification (COAP) are commonly used technologies in thermal power plants to achieve synergistic removal of multiple pollutants. The SCR unit is located downstream of the economizer, removing nitrogen oxides through ammonia injection catalytic reaction; the COAP unit utilizes the principle of low-temperature adsorption to deeply purify the desulfurized flue gas. In some retrofit schemes, a three-way valve is installed at the economizer outlet, with one channel of flue gas directly entering the SCR reactor, and the other channel entering the COAP purification inlet after being cooled by heat exchange coils, forming a dual-channel flue structure.

[0003] In current practical engineering applications, SCR and COAP systems typically employ independent control strategies. Data such as unit load, SCR inlet and outlet nitrogen oxide concentrations, flue gas temperature, and COAP inlet sulfur dioxide concentration are transmitted to their respective controllers, lacking a unified hierarchical collaborative adaptive control logic between the two systems. When the unit is under low load, the economizer outlet flue gas temperature is below the catalyst activation temperature window, leading to a decrease in SCR denitrification efficiency. Simply increasing ammonia injection to suppress outlet nitrogen oxides would cause a sharp increase in ammonia slip, resulting in excessive ammonia entering subsequent systems and causing secondary problems such as air preheater blockage. When the unit is under high load, the flue gas temperature rises, and SCR efficiency recovers. However, if the COAP unit continues its original cryogenic operation mode, it will result in unnecessary energy waste. Summary of the Invention

[0004] The purpose of this invention is to provide a flue gas purification coupled and coordinated control method, device and medium to solve the technical problems existing in the background art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for coupled and coordinated control of flue gas purification, comprising: Acquire data on the unit load, SCR inlet flue gas temperature, and flue gas pollutant concentration of the thermal power unit. The flue gas pollutant concentration data includes at least the SCR inlet NOx concentration, the SCR outlet NOx concentration, and the COAP inlet SO2 concentration. Determine the load range based on the unit load; Based on the load range, the NOx concentration at the SCR inlet, the NOx concentration at the SCR outlet, the flue gas temperature at the SCR inlet, and the SO2 concentration at the COAP inlet, determine the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle. Based on the ammonia injection flow rate, an SCR ammonia injection quantity control command is generated; based on the bypass flue gas ratio, a flue gas diversion control command is generated; based on the COAP cooling temperature, a COAP cooling temperature control command is generated; based on the adsorbent regeneration cycle, an adsorbent regeneration control command is generated; and based on the load range, an escape ammonia diversion control command and an acid gas reflux control command are generated. The ammonia injection rate of the ammonia injection dilution blower is controlled according to the SCR ammonia injection rate control command. According to the flue gas diversion control command, the opening of the flue gas diversion three-way valve is controlled to adjust the ratio of flue gas entering the SCR reactor from the main flue and the bypass flue with heat exchange coils that converge into the COAP purification inlet. According to the escaped ammonia diversion control command, control the valve of the SCR outlet clean flue gas diversion branch pipe to divert the clean flue gas carrying escaped ammonia from the SCR outlet to the COAP adsorption chamber as an auxiliary adsorption agent. The COAP cooling temperature setting is controlled according to the COAP cooling temperature control command. The COAP adsorbent regeneration cycle is controlled according to the adsorbent regeneration control command. According to the acid gas reflux control command, the valve of the COAP desorption and regeneration outlet reflux pipeline is controlled to reflux the acid gas generated by COAP desorption and regeneration back to the secondary catalytic decomposition in the flue gas duct before SCR.

[0006] It should be noted that this invention obtains unified data on unit load, flue gas temperature, and pollutant concentration, determines ammonia injection flow rate, bypass flue gas ratio, cooling temperature, and regeneration cycle based on load interval linkage, and generates commands to control the corresponding actuators. Simultaneously, it independently generates commands for ammonia escape diversion and acid gas recirculation based on load intervals, controlling the corresponding valve actions. Thus, the SCR denitrification and COAP low-temperature purification systems achieve parameter adaptive matching under full unit load conditions. Furthermore, the ammonia escaped from the SCR outlet is introduced into the COAP adsorption chamber for adsorption, and the desorbed acid gas from the COAP chamber is recirculated back to the SCR pre-flue, achieving material circulation coupling between the two systems. This ensures stable ultra-low emissions of multiple pollutants while reducing adsorbent replacement frequency and lowering system energy consumption.

[0007] Furthermore, the load range is divided into low load range, medium load range, or high load range based on the pre-set unit output. When the load range is a low load range, the SCR ammonia injection control command is a command to dynamically adjust and increase the ammonia injection amount by partitioning, the flue gas diversion control command is a command to open the economizer water bypass to increase the SCR inlet flue gas temperature, the COAP cooling temperature control command is a command to switch to the preset cryogenic setting, and the adsorbent regeneration control command is a command to extend the adsorbent regeneration cycle. When the load range is a high load range, the SCR ammonia injection quantity control command is a command for precise low ammonia injection, the flue gas diversion control command is a command to close a preset portion of the economizer water bypass, and the COAP cooling temperature control command is a command to switch to a preset shallow cooling mode. When the load range is the medium load range, the SCR ammonia injection control command, the flue gas diversion control command, and the COAP cooling temperature control command are all transition control commands, so that the SCR ammonia injection rate, economizer water bypass opening and COAP cooling temperature smoothly transition between preset shallow cooling and preset deep cooling.

[0008] It should be noted that this invention divides the load into three ranges—low, medium, and high—based on the unit's output, and outputs corresponding differentiated control commands for ammonia injection, flue gas diversion ratio, cooling level, and regeneration cycle. At low load, the flue gas temperature is increased by opening the bypass and switching to deep cooling to enhance purification. At high load, some bypasses are closed and shallow cooling is switched to reduce energy consumption. At medium load, the parameters transition smoothly, ensuring that the SCR and COAP systems maintain coordinated matching of control parameters throughout the unit's full load variation process. This ensures stable ultra-low emissions of multiple pollutants such as nitrogen oxides and sulfur dioxide while avoiding the problems of ammonia escape exacerbation at low load or energy waste at high load.

[0009] Furthermore, the flue gas pollutant concentration data also includes SCR outlet ammonia slip, COAP inlet heavy metal concentration, COAP inlet dust concentration, unit main steam flow rate, and economizer outlet water temperature; based on the load range, SCR inlet NOx concentration, SCR outlet NOx concentration, SCR inlet flue gas temperature, and COAP inlet SO2 concentration, the ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle are determined, including: Based on the load range, the NOx concentration at the SCR inlet, the NOx concentration at the SCR outlet, the flue gas temperature at the SCR inlet, the SO2 concentration at the COAP inlet, the ammonia slip at the SCR outlet, the heavy metal concentration at the COAP inlet, the dust concentration at the COAP inlet, the main steam flow rate of the unit, and the water temperature at the economizer outlet, an improved particle swarm optimization algorithm is used to synchronously optimize and output the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle.

[0010] It should be noted that, based on the original nitrogen oxide and sulfur dioxide concentrations, this invention further introduces multi-dimensional operating parameters such as ammonia slip, heavy metal concentration, dust concentration, main steam flow rate, and economizer outlet water temperature. An improved particle swarm optimization algorithm is used to simultaneously optimize ammonia injection flow rate, bypass flue gas ratio, cooling temperature, and adsorbent regeneration cycle. This allows the determination of control parameters to comprehensively consider the coupling relationship between unit load, flue gas temperature, and the concentrations of multiple pollutants. Through multi-objective collaborative calculation, the optimal command combination is output, thereby maintaining adaptive matching of parameters between the SCR denitrification and COAP low-temperature purification systems when the unit load changes or flue gas conditions fluctuate, achieving stable collaborative control of multiple pollutants.

[0011] Furthermore, in the improved particle swarm optimization algorithm, the particle position vector includes four dimensions: the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle. The fitness function is a weighted sum of minimizing the total pollutant concentration at the outlet and minimizing the system energy consumption.

[0012] It should be noted that the improved particle swarm optimization algorithm of this invention encodes the ammonia injection flow rate, bypass flue gas ratio, cooling temperature, and regeneration cycle into particle position vectors. It uses the weighted sum of minimizing the total pollutant concentration at the outlet and minimizing system energy consumption as the fitness function for synchronous optimization. This allows the algorithm to output four sets of control parameters that achieve the comprehensive optimal balance between environmental emissions and economic operation in a single iteration. This avoids the repeated debugging caused by the conflict between multiple objectives in the traditional independent control method, thereby reducing the overall energy consumption of the system while ensuring the synergistic removal effect of multiple pollutants.

[0013] Furthermore, it also includes: Real-time collection of total pollutant concentrations at the outlet, including the final emission concentrations of NOx, SO2, heavy metals, and dust; Based on the total pollutant concentration at the outlet, the fitness function of the improved particle swarm optimization algorithm is rolled over and corrected, and the ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle are re-output.

[0014] It should be noted that after outputting the control parameters, this invention also collects the concentrations of nitrogen oxides, sulfur dioxide, heavy metals, and dust in real time. Based on this, it performs rolling corrections on the fitness function of the improved particle swarm optimization algorithm, and re-outputs the ammonia injection flow rate, bypass flue gas ratio, cooling temperature, and regeneration cycle. This allows the optimization algorithm to use the actual emission effect as a feedback signal and dynamically adjust its optimization direction. Therefore, when the unit's operating conditions fluctuate or equipment performance changes, the control system can adaptively correct various parameters online without manual reset, thus maintaining a comprehensive balance between the synergistic purification effect of multiple pollutants and system energy consumption during long-term operation.

[0015] Furthermore, the method of diverting the clean flue gas carrying escaped ammonia from the SCR outlet to the COAP adsorption chamber as an auxiliary adsorption agent includes: The clean flue gas from the SCR outlet is introduced into the COAP adsorption chamber through a branch pipe located at the SCR outlet. The escaped ammonia is used as an auxiliary adsorbent for COAP adsorption of acidic pollutants to enhance the adsorption of acidic pollutants.

[0016] It should be noted that the present invention introduces the clean flue gas into the COAP adsorption chamber through a branch pipe set at the SCR outlet, and uses the escaped ammonia originally carried in the flue gas as an auxiliary adsorption agent to participate in the adsorption reaction of acidic pollutants. This allows the ammonia that has not been fully reacted in the SCR system to be reused in the COAP system. Thus, without the need for additional chemical reagents, the adsorption capacity of the COAP device for acidic pollutants is enhanced, and the emission of residual ammonia in the clean flue gas is reduced.

[0017] Furthermore, the step of recirculating the acidic gas generated by COAP desorption and regeneration to the SCR pre-flue for secondary catalytic decomposition includes: The acidic gas generated by the desorption of the COAP saturated adsorbent is transported to the SCR pre-flue through a reflux pipeline, where the acidic gas undergoes secondary catalytic decomposition under the action of the SCR catalyst.

[0018] It should be noted that the present invention delivers the acidic gas generated by the desorption of the COAP saturated adsorbent to the SCR pre-flue through a return pipeline, and uses the existing SCR catalyst there to perform secondary catalytic decomposition of the acidic gas. This allows the acidic gas, which originally needed to be treated separately at the back end, to be synergistically purified in the front-end denitrification system, thereby eliminating the need for additional treatment devices for the desorbed acidic gas, simplifying the system architecture, and improving the overall purification efficiency of flue gas pollutants.

[0019] Furthermore, the COAP cooling temperature settings correspond to the COAP's built-in three-level adjustable cooling circuit, which includes a preset deep cooling setting, a 0°C cooling setting, and a preset shallow cooling setting. When controlling the COAP cooling temperature setting, a linkage power supply signal is simultaneously output to the cooling heat pump power supply, the ammonia injection dilution fan, and the economizer bypass regulating valve, so that the cooling heat pump, the ammonia injection dilution fan, and the economizer bypass regulating valve perform linkage power supply.

[0020] It should be noted that, when controlling the COAP cooling temperature setting, this invention simultaneously outputs a linkage power supply signal to the cooling heat pump power supply, the ammonia injection dilution fan, and the economizer bypass regulating valve. This allows the aforementioned key equipment to be energized and activated synchronously with the temperature setting switching during load fluctuations, thereby integrating multiple actuators that originally required independent adjustment into a unified linkage response mode. This linkage method reduces repeated communication and iterative calculations between controllers, shortens the response time of multi-device coordinated action, and enables the rapid establishment of a matched operating state between the SCR and COAP systems under variable load conditions, maintaining the stability of the flue gas purification process.

[0021] In a second aspect, the present invention provides an electronic device including a processor and a memory, the processor being configured to execute a computer program stored in the memory to perform: Acquire data on the unit load, SCR inlet flue gas temperature, and flue gas pollutant concentration of the thermal power unit. The flue gas pollutant concentration data includes at least the SCR inlet NOx concentration, the SCR outlet NOx concentration, and the COAP inlet SO2 concentration. Determine the load range based on the unit load; Based on the load range, the NOx concentration at the SCR inlet, the NOx concentration at the SCR outlet, the flue gas temperature at the SCR inlet, and the SO2 concentration at the COAP inlet, determine the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle. Based on the ammonia injection flow rate, an SCR ammonia injection quantity control command is generated; based on the bypass flue gas ratio, a flue gas diversion control command is generated; based on the COAP cooling temperature, a COAP cooling temperature control command is generated; based on the adsorbent regeneration cycle, an adsorbent regeneration control command is generated; and based on the load range, an escape ammonia diversion control command and an acid gas reflux control command are generated. The ammonia injection rate of the ammonia injection dilution blower is controlled according to the SCR ammonia injection rate control command. According to the flue gas diversion control command, the opening of the flue gas diversion three-way valve is controlled to adjust the ratio of flue gas entering the SCR reactor from the main flue and the bypass flue with heat exchange coils that converge into the COAP purification inlet. According to the escaped ammonia diversion control command, control the valve of the SCR outlet clean flue gas diversion branch pipe to divert the clean flue gas carrying escaped ammonia from the SCR outlet to the COAP adsorption chamber as an auxiliary adsorption agent. The COAP cooling temperature setting is controlled according to the COAP cooling temperature control command. The COAP adsorbent regeneration cycle is controlled according to the adsorbent regeneration control command. According to the acid gas reflux control command, the valve of the COAP desorption and regeneration outlet reflux pipeline is controlled to reflux the acid gas generated by COAP desorption and regeneration back to the secondary catalytic decomposition in the flue gas duct before SCR.

[0022] In a third aspect, the present invention provides a computer-readable storage medium storing at least one instruction that is implemented when executed by a processor: Acquire data on the unit load, SCR inlet flue gas temperature, and flue gas pollutant concentration of the thermal power unit. The flue gas pollutant concentration data includes at least the SCR inlet NOx concentration, the SCR outlet NOx concentration, and the COAP inlet SO2 concentration. Determine the load range based on the unit load; Based on the load range, the NOx concentration at the SCR inlet, the NOx concentration at the SCR outlet, the flue gas temperature at the SCR inlet, and the SO2 concentration at the COAP inlet, determine the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle. Based on the ammonia injection flow rate, an SCR ammonia injection quantity control command is generated; based on the bypass flue gas ratio, a flue gas diversion control command is generated; based on the COAP cooling temperature, a COAP cooling temperature control command is generated; based on the adsorbent regeneration cycle, an adsorbent regeneration control command is generated; and based on the load range, an escape ammonia diversion control command and an acid gas reflux control command are generated. The ammonia injection rate of the ammonia injection dilution blower is controlled according to the SCR ammonia injection rate control command. According to the flue gas diversion control command, the opening of the flue gas diversion three-way valve is controlled to adjust the ratio of flue gas entering the SCR reactor from the main flue and the bypass flue with heat exchange coils that converge into the COAP purification inlet. According to the escaped ammonia diversion control command, control the valve of the SCR outlet clean flue gas diversion branch pipe to divert the clean flue gas carrying escaped ammonia from the SCR outlet to the COAP adsorption chamber as an auxiliary adsorption agent. The COAP cooling temperature setting is controlled according to the COAP cooling temperature control command. The COAP adsorbent regeneration cycle is controlled according to the adsorbent regeneration control command. According to the acid gas reflux control command, the valve of the COAP desorption and regeneration outlet reflux pipeline is controlled to reflux the acid gas generated by COAP desorption and regeneration back to the secondary catalytic decomposition in the flue gas duct before SCR.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention obtains unified data on unit load, flue gas temperature, and pollutant concentration. Based on load range linkage, it determines ammonia injection flow rate, bypass flue gas ratio, cooling temperature, and regeneration cycle, generating commands to control corresponding actuators. Simultaneously, it independently generates commands for ammonia escape diversion and acid gas recirculation based on load ranges, controlling corresponding valve actions. Thus, the SCR denitrification and COAP low-temperature purification systems achieve parameter adaptive matching under full unit load conditions. Furthermore, ammonia escape from the SCR outlet is introduced into the COAP adsorption chamber for adsorption, while the desorbed acid gas from the COAP chamber is recirculated back to the SCR pre-flue, achieving material circulation coupling between the two systems. This ensures stable ultra-low emissions of multiple pollutants while reducing adsorbent replacement frequency and lowering system energy consumption. Attached Figure Description

[0024] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a flowchart illustrating a flue gas purification coupled and coordinated control method provided in an embodiment of the present invention. Figure 2 This is an overall flue gas flow diagram of the SCR and COAP coupled flue gas system provided in an embodiment of the present invention; Figure 3 This is a partially enlarged view of the three-way flue gas diversion bypass heat exchange structure provided in an embodiment of the present invention; Figure 4 This is a hardware wiring diagram for hierarchical collaborative adaptive control provided in an embodiment of the present invention; Figure 5 The flowchart of the full-load zone control logic algorithm provided in the embodiment of the present invention; Figure 6 This is a structural diagram of the COAP adsorbent regeneration flue gas return pipeline provided in an embodiment of the present invention; Figure 7 This is a structural block diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0025] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0026] The following detailed description is exemplary and intended to provide further detailed explanation of the invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention.

[0027] Example 1 This application provides a flowchart illustrating a coupled and coordinated control method for flue gas purification, as shown below. Figure 1 As shown, this process can be executed by a flue gas purification coupled and coordinated control system. Certain input parameters or intermediate results in the process can be manually adjusted to help improve accuracy.

[0028] The method flow steps of this application embodiment are as follows: S101, acquire the unit load, SCR inlet flue gas temperature and flue gas pollutant concentration data of the thermal power unit, wherein the flue gas pollutant concentration data includes at least the SCR inlet NOx concentration, SCR outlet NOx concentration and COAP inlet SO2 concentration.

[0029] In the embodiments described in this specification, online monitoring instruments are arranged at key nodes in the boiler tail flue. A NOx concentration sensor and a temperature sensor are installed in the SCR reactor inlet flue to collect the SCR inlet NOx concentration and SCR inlet flue temperature; a NOx concentration sensor is installed in the SCR reactor outlet flue to collect the SCR outlet NOx concentration; and an SO2 concentration sensor is installed in the COAP purification unit inlet flue to collect the COAP inlet SO2 concentration. The unit load signal is directly obtained from the unit's distributed control system. The above real-time data is transmitted to the central controller via an industrial communication bus as input for subsequent control logic.

[0030] S102, determine the load range based on the unit load.

[0031] In the embodiments described in this specification, the central controller pre-stores unit load range division standards, dividing the unit output range into low load, medium load, and high load zones. After reading the current unit load signal, the controller compares it with the preset load range threshold to determine the current load range of the unit, providing a judgment benchmark for the selection of subsequent differentiated control strategies.

[0032] S103, based on the load range, the NOx concentration at the SCR inlet, the NOx concentration at the SCR outlet, the flue gas temperature at the SCR inlet, and the SO2 concentration at the COAP inlet, determine the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle.

[0033] In the embodiments described in this specification, the controller invokes preset control logic, taking the load range determination result, SCR inlet NOx concentration, SCR outlet NOx concentration, SCR inlet flue gas temperature, and COAP inlet SO2 concentration as input conditions. Through table lookup or algorithm calculation, four sets of control parameters are simultaneously output: ammonia injection flow rate setpoint, bypass flue gas ratio setpoint, COAP cooling temperature setpoint, and adsorbent regeneration cycle setpoint. These four sets of parameters are used to generate corresponding control commands in subsequent steps.

[0034] S104, generate an SCR ammonia injection quantity control command based on the ammonia injection flow rate, generate a flue gas diversion control command based on the bypass flue gas ratio, generate a COAP cooling temperature control command based on the COAP cooling temperature, generate an adsorbent regeneration control command based on the adsorbent regeneration cycle, and generate an escape ammonia diversion control command and an acid gas reflux control command based on the load range.

[0035] In the embodiments described in this specification, the controller generates corresponding control commands based on the four sets of parameters output in S103: an SCR ammonia injection control command based on the ammonia injection flow rate, a flue gas diversion control command based on the bypass flue gas ratio, a COAP cooling temperature control command based on the COAP cooling temperature, and an adsorbent regeneration control command based on the adsorbent regeneration cycle. Simultaneously, based on the load range determined in S102, the controller additionally generates escape ammonia diversion control commands and acid gas recirculation control commands to independently control subsequent material circulation coupling actions.

[0036] S105, according to the SCR ammonia injection quantity control command, control the ammonia injection quantity of the ammonia dilution fan.

[0037] In the embodiments described in this specification, the controller sends the SCR ammonia injection control command to the frequency converter or regulating valve of the ammonia dilution fan. The actuator adjusts the speed of the dilution fan or the valve opening according to the command, thereby changing the ammonia flow rate injected into the inlet flue of the SCR reactor, and realizing the control of the ammonia injection rate for the SCR denitrification reaction.

[0038] S106, according to the flue gas diversion control command, control the opening of the flue gas diversion three-way valve to adjust the ratio of flue gas entering the main flue into the SCR reactor and the bypass flue equipped with heat exchange coils that converge into the COAP purification inlet.

[0039] In the embodiments described in this specification, the controller sends a flue gas diversion control command to the flue gas diversion three-way valve actuator at the economizer outlet. The actuator adjusts the opening of the three-way valve according to the command, changing the flue gas distribution ratio between the main flue and the bypass flue. A portion of the flue gas directly enters the SCR reactor for denitrification, while the other portion is cooled by the heat exchange coil and then flows into the COAP purification inlet, forming a dual-channel flue structure.

[0040] S107, according to the escaped ammonia diversion control command, control the valve of the SCR outlet clean flue gas diversion branch pipe to divert the clean flue gas carrying escaped ammonia from the SCR outlet to the COAP adsorption chamber as an auxiliary adsorption agent.

[0041] In the embodiments described in this specification, the controller sends an escaped ammonia diversion control command to the valve actuator on the SCR outlet clean flue gas diversion branch. The actuator opens or adjusts the valve according to the command, introducing the clean flue gas carrying trace amounts of escaped ammonia from the SCR outlet into the COAP adsorption chamber. This escaped ammonia acts as an auxiliary adsorption agent within the COAP adsorption chamber, participating in the adsorption reaction of acidic pollutants.

[0042] S108, control the COAP cooling temperature setting according to the COAP cooling temperature control command.

[0043] In the embodiments described in this specification, the controller sends the COAP cooling temperature control command to the switching device of the three-level adjustable cooling circuit built into the COAP. The actuator switches the cooling level according to the command, selecting between a preset deep cooling level, a 0°C cooling level, and a preset shallow cooling level, so that the COAP device operates in the corresponding cooling temperature range.

[0044] S109, control the COAP adsorbent regeneration cycle according to the adsorbent regeneration control command.

[0045] In the embodiments described in this specification, the controller sends adsorbent regeneration control commands to the actuator of the COAP regeneration control valve assembly. The actuator adjusts the valve assembly's operating frequency or opening duration according to the commands, thereby controlling the COAP adsorbent regeneration cycle and determining the interval between saturated adsorbent entering desorption regeneration.

[0046] S110, according to the acid gas reflux control command, control the valve of the COAP desorption and regeneration outlet reflux pipeline to reflux the acid gas generated by COAP desorption and regeneration to the secondary catalytic decomposition in the SCR pre-flue.

[0047] In the embodiments described in this specification, the controller sends an acid gas reflux control command to the valve actuator on the COAP desorption and regeneration outlet reflux pipeline. The actuator opens or adjusts the valve according to the command, allowing the acid gas generated by the desorption of the COAP saturated adsorbent to be transported to the SCR pre-flue through the reflux pipeline. This portion of acid gas undergoes secondary catalytic decomposition under the action of the SCR catalyst, completing the material cycle coupling between the two systems.

[0048] It should be noted that this invention obtains unified data on unit load, flue gas temperature, and pollutant concentration, determines ammonia injection flow rate, bypass flue gas ratio, cooling temperature, and regeneration cycle based on load interval linkage, and generates commands to control the corresponding actuators. Simultaneously, it independently generates commands for ammonia escape diversion and acid gas recirculation based on load intervals, controlling the corresponding valve actions. Thus, the SCR denitrification and COAP low-temperature purification systems achieve parameter adaptive matching under full unit load conditions. Furthermore, the ammonia escaped from the SCR outlet is introduced into the COAP adsorption chamber for adsorption, and the desorbed acid gas from the COAP chamber is recirculated back to the SCR pre-flue, achieving material circulation coupling between the two systems. This ensures stable ultra-low emissions of multiple pollutants while reducing adsorbent replacement frequency and lowering system energy consumption.

[0049] Furthermore, the load range is divided into low load range, medium load range, or high load range based on the pre-set unit output. When the load range is a low load range, the SCR ammonia injection control command is a command to dynamically adjust and increase the ammonia injection amount by partitioning, the flue gas diversion control command is a command to open the economizer water bypass to increase the SCR inlet flue gas temperature, the COAP cooling temperature control command is a command to switch to the preset cryogenic setting, and the adsorbent regeneration control command is a command to extend the adsorbent regeneration cycle.

[0050] When the load range is a high load range, the SCR ammonia injection control command is a command for precise low ammonia injection, the flue gas diversion control command is a command to close a preset portion of the economizer water bypass, and the COAP cooling temperature control command is a command to switch to a preset shallow cooling mode.

[0051] When the load range is the medium load range, the SCR ammonia injection control command, the flue gas diversion control command, and the COAP cooling temperature control command are all transition control commands, so that the SCR ammonia injection rate, economizer water bypass opening and COAP cooling temperature smoothly transition between preset shallow cooling and preset deep cooling.

[0052] It should be noted that this invention divides the load into three ranges—low, medium, and high—based on the unit's output, and outputs corresponding differentiated control commands for ammonia injection, flue gas diversion ratio, cooling level, and regeneration cycle. At low load, the flue gas temperature is increased by opening the bypass and switching to deep cooling to enhance purification. At high load, some bypasses are closed and shallow cooling is switched to reduce energy consumption. At medium load, the parameters transition smoothly, ensuring that the SCR and COAP systems maintain coordinated matching of control parameters throughout the unit's full load variation process. This ensures stable ultra-low emissions of multiple pollutants such as nitrogen oxides and sulfur dioxide while avoiding the problems of ammonia escape exacerbation at low load or energy waste at high load.

[0053] Furthermore, the flue gas pollutant concentration data also includes SCR outlet ammonia slip, COAP inlet heavy metal concentration, COAP inlet dust concentration, main steam flow rate, and economizer outlet water temperature; the method flow steps of this application embodiment in determining the ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle based on the load range, SCR inlet NOx concentration, SCR outlet NOx concentration, SCR inlet flue gas temperature, and COAP inlet SO2 concentration are as follows: S201, based on the load range, the NOx concentration at the SCR inlet, the NOx concentration at the SCR outlet, the flue gas temperature at the SCR inlet, the SO2 concentration at the COAP inlet, the ammonia slip at the SCR outlet, the heavy metal concentration at the COAP inlet, the dust concentration at the COAP inlet, the main steam flow rate of the unit, and the water temperature at the economizer outlet, an improved particle swarm optimization algorithm is used to synchronously optimize and output the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle.

[0054] In this embodiment of the specification, based on the basic data acquisition completed in step S101, the controller further acquires extended operating parameters through additional online monitoring instruments. A laser ammonia slip analyzer is installed in the SCR outlet flue to collect the SCR outlet ammonia slip; an online heavy metal monitor and a dust concentration meter are installed in the COAP inlet flue to collect the COAP inlet heavy metal concentration and COAP inlet dust concentration, respectively; the unit's main steam flow signal is obtained from the unit's distributed control system; and the economizer outlet water temperature is collected by a temperature sensor installed on the economizer outlet pipeline. The above extended parameters, together with the unit load, SCR inlet flue gas temperature, SCR inlet NOx concentration, SCR outlet NOx concentration, COAP inlet SO2 concentration already acquired in S101, and the load range determined in S102, constitute a complete input dataset.

[0055] The controller has a pre-installed improved particle swarm optimization (PSO) algorithm. During algorithm initialization, four parameters to be determined—ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle—are encoded as particle position vectors, forming a four-dimensional search space. The algorithm uses the weighted sum of minimizing the total outlet pollutant concentration and minimizing system energy consumption as the fitness evaluation criterion, where the total outlet pollutant concentration includes NOx, SO2, heavy metals, and dust.

[0056] In each iteration, the algorithm evaluates the fitness of the parameter combination corresponding to each particle based on the current load range, SCR inlet and outlet NOx concentrations, SCR inlet flue gas temperature, COAP inlet SO2 concentration, SCR outlet ammonia slip, COAP inlet heavy metal concentration, COAP inlet dust concentration, unit main steam flow rate, and economizer outlet water temperature. By updating the particle's velocity and position, it gradually moves closer to the optimal solution. After a preset number of iterations or when the convergence condition is met, the algorithm outputs the optimal ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle, which serve as the basis for generating control commands in step S104.

[0057] It should be noted that, based on the original nitrogen oxide and sulfur dioxide concentrations, this invention further introduces multi-dimensional operating parameters such as ammonia slip, heavy metal concentration, dust concentration, main steam flow rate, and economizer outlet water temperature. An improved particle swarm optimization algorithm is used to simultaneously optimize ammonia injection flow rate, bypass flue gas ratio, cooling temperature, and adsorbent regeneration cycle. This allows the determination of control parameters to comprehensively consider the coupling relationship between unit load, flue gas temperature, and the concentrations of multiple pollutants. Through multi-objective collaborative calculation, the optimal command combination is output, thereby maintaining adaptive matching of parameters between the SCR denitrification and COAP low-temperature purification systems when the unit load changes or flue gas conditions fluctuate, achieving stable collaborative control of multiple pollutants.

[0058] Furthermore, in the improved particle swarm optimization algorithm, the particle position vector includes four dimensions: the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle. The fitness function is a weighted sum of minimizing the total pollutant concentration at the outlet and minimizing the system energy consumption.

[0059] It should be noted that the improved particle swarm optimization algorithm of this invention encodes the ammonia injection flow rate, bypass flue gas ratio, cooling temperature, and regeneration cycle into particle position vectors. It uses the weighted sum of minimizing the total pollutant concentration at the outlet and minimizing system energy consumption as the fitness function for synchronous optimization. This allows the algorithm to output four sets of control parameters that achieve the comprehensive optimal balance between environmental emissions and economic operation in a single iteration. This avoids the repeated debugging caused by the conflict between multiple objectives in the traditional independent control method, thereby reducing the overall energy consumption of the system while ensuring the synergistic removal effect of multiple pollutants.

[0060] Furthermore, after outputting the control parameters, the method flow steps of this application embodiment are as follows: S301, real-time collection of total pollutant concentration at the outlet, including the final emission concentrations of NOx, SO2, heavy metals, and dust.

[0061] In the embodiments described in this specification, a multi-pollutant continuous monitoring device is installed at the main exhaust outlet of the flue gas purification system. Specifically, a NOx analyzer, an SO2 analyzer, a heavy metal monitor, and a dust concentration meter are installed at the chimney inlet flue. The monitoring device extracts flue gas samples in real time according to a set sampling period for analysis, obtaining the total pollutant concentration at the outlet. This concentration data includes the final emission concentrations of NOx, SO2, heavy metals, and dust. The collected concentration data is transmitted to the central controller via an industrial communication network as a feedback signal for evaluating the current purification effect.

[0062] S302, based on the total pollutant concentration at the outlet, the fitness function of the improved particle swarm optimization algorithm is rolled over and corrected, and the ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle are re-output.

[0063] In the embodiments described in this specification, the controller compares the total pollutant concentration at the outlet obtained in S301 with the system's historical operating data or target requirements. Based on this comparison, it performs rolling corrections on the fitness function of the improved particle swarm optimization algorithm in step S201. Specifically, this is achieved by adjusting the weighting coefficients between minimizing pollutant concentration and minimizing system energy consumption in the fitness function, or by updating the target constraint boundaries. After the fitness function correction is completed, the controller uses the latest full-scale operating data as input to re-drive the improved particle swarm optimization algorithm to perform synchronous optimization calculations, outputting updated ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle. The re-output parameters are fed back to step S104 to replace the original parameters and generate new control commands, ensuring that the control actions in S105 to S110 are executed according to the latest optimization results.

[0064] It should be noted that after outputting the control parameters, this invention also collects the concentrations of nitrogen oxides, sulfur dioxide, heavy metals, and dust in real time. Based on this, it performs rolling corrections on the fitness function of the improved particle swarm optimization algorithm, and re-outputs the ammonia injection flow rate, bypass flue gas ratio, cooling temperature, and regeneration cycle. This allows the optimization algorithm to use the actual emission effect as a feedback signal and dynamically adjust its optimization direction. Therefore, when the unit's operating conditions fluctuate or equipment performance changes, the control system can adaptively correct various parameters online without manual reset, thus maintaining a comprehensive balance between the synergistic purification effect of multiple pollutants and system energy consumption during long-term operation.

[0065] Furthermore, in the process of diverting the clean flue gas carrying escaped ammonia from the SCR outlet to the COAP adsorption chamber as an auxiliary adsorption agent, the method flow steps of this application embodiment are as follows: S401, the clean flue gas from the SCR outlet is introduced into the COAP adsorption chamber through a branch pipe installed at the SCR outlet, and the escaped ammonia is used as an auxiliary adsorbent for COAP adsorption of acidic pollutants to enhance the adsorption of acidic pollutants.

[0066] In the embodiments described in this specification, after the controller opens the valve of the SCR outlet flue gas diversion branch in step S107, the flue gas from the SCR reactor outlet enters the COAP adsorption chamber through this diversion branch. Since the SCR outlet flue gas contains trace amounts of ammonia that escaped during the denitrification process, this escaped ammonia acts as an auxiliary adsorption agent in the COAP adsorption chamber, working synergistically with the adsorption material to adsorb acidic pollutants in the flue gas, thereby enhancing the adsorption effect on acidic pollutants.

[0067] It should be noted that the present invention introduces the clean flue gas into the COAP adsorption chamber through a branch pipe set at the SCR outlet, and uses the escaped ammonia originally carried in the flue gas as an auxiliary adsorption agent to participate in the adsorption reaction of acidic pollutants. This allows the ammonia that has not been fully reacted in the SCR system to be reused in the COAP system. Thus, without the need for additional chemical reagents, the adsorption capacity of the COAP device for acidic pollutants is enhanced, and the emission of residual ammonia in the clean flue gas is reduced.

[0068] Furthermore, in the process of recirculating the acidic gas generated by COAP desorption and regeneration to the SCR pre-flue for secondary catalytic decomposition, the method flow steps of this application embodiment are as follows: S501, the acidic gas generated by the desorption of the COAP saturated adsorbent is transported to the SCR front flue through the return pipeline, so that the acidic gas undergoes secondary catalytic decomposition under the action of the SCR catalyst.

[0069] In the embodiments described in this specification, after the COAP adsorbent completes regeneration and desorption in step S109, the acidic gas released by the saturated adsorbent during desorption is collected at the COAP desorption and regeneration outlet. At this time, in step S110, the controller has opened the reflux pipeline valve according to the acidic gas reflux control command, and the acidic gas is transported to the SCR pre-flue through the reflux pipeline. Since the SCR pre-flue is equipped with an SCR catalyst, the refluxed acidic gas undergoes a secondary catalytic decomposition reaction under the action of the catalyst when flowing through the catalyst layer, transforming into harmless substances and forming a material cycle coupling with the SCR denitrification process.

[0070] It should be noted that the present invention delivers the acidic gas generated by the desorption of the COAP saturated adsorbent to the SCR pre-flue through a return pipeline, and uses the existing SCR catalyst there to perform secondary catalytic decomposition of the acidic gas. This allows the acidic gas, which originally needed to be treated separately at the back end, to be synergistically purified in the front-end denitrification system, thereby eliminating the need for additional treatment devices for the desorbed acidic gas, simplifying the system architecture, and improving the overall purification efficiency of flue gas pollutants.

[0071] Furthermore, the COAP cooling temperature settings correspond to the COAP's built-in three-level adjustable cooling circuit, which includes a preset deep cooling setting, a 0°C cooling setting, and a preset shallow cooling setting. The method flow steps for controlling the COAP cooling temperature settings in this embodiment are as follows: S601 synchronously outputs a linkage power supply signal to the cooling heat pump power supply, the ammonia injection dilution fan, and the economizer bypass regulating valve, so that the cooling heat pump, the ammonia injection dilution fan, and the economizer bypass regulating valve can perform linkage power supply.

[0072] In this embodiment of the specification, this step is executed simultaneously when the controller switches the COAP cooling temperature level according to the COAP cooling temperature control command in step S108. The COAP cooling temperature level corresponds to the three-level adjustable cooling circuit built into the COAP, which includes a preset deep cooling level, a 0°C cooling level, and a preset shallow cooling level. When the controller sends the level switching command to the three-level adjustable cooling circuit, it generates a linkage power supply signal and transmits the signal to the power supply control terminals of the cooling heat pump power supply, the ammonia dilution fan, and the economizer bypass regulating valve, respectively. After receiving the linkage power supply signal, the cooling heat pump, the ammonia dilution fan, and the economizer bypass regulating valve perform a linkage power supply operation, so that the above-mentioned equipment is powered on synchronously with the switching of the cooling temperature level, thereby realizing the coordinated response of the cooling system and related equipment under variable load conditions.

[0073] It should be noted that, when controlling the COAP cooling temperature setting, this invention simultaneously outputs a linkage power supply signal to the cooling heat pump power supply, the ammonia injection dilution fan, and the economizer bypass regulating valve. This allows the aforementioned key equipment to be energized and activated synchronously with the temperature setting switching during load fluctuations, thereby integrating multiple actuators that originally required independent adjustment into a unified linkage response mode. This linkage method reduces repeated communication and iterative calculations between controllers, shortens the response time of multi-device coordinated action, and enables the rapid establishment of a matched operating state between the SCR and COAP systems under variable load conditions, maintaining the stability of the flue gas purification process.

[0074] This invention comprises three main parts: a coupled flue gas duct hardware system, a multi-parameter sensing and monitoring module, and a hierarchical collaborative adaptive controller, to achieve full-load NO xCombined removal of SO2, heavy metals, and dust: 1. SCR and COAP dual-channel coupled flue hardware architecture The boiler economizer outlet is equipped with a flue gas diversion three-way valve, one of which is the main flue gas duct that enters the SCR reactor; the other bypass flue gas duct is equipped with a flue gas heat exchange coil, and after heat exchange, it flows into the COAP low-temperature purification inlet. The SCR outlet flue gas is supplied with a branch pipe to carry a trace amount of escaped ammonia into the COAP adsorption chamber as an auxiliary adsorption agent; the acidic gas generated by COAP desorption and regeneration is returned to the flue gas duct before SCR for secondary catalytic decomposition. The COAP has a built-in three-stage adjustable cooling circuit (20℃ / 0℃ / -20℃), and the cooling heat pump power supply is linked to the SCR ammonia injection dilution fan and the economizer bypass regulating valve for power supply logic.

[0075] 2. Multi-dimensional online sensing and monitoring module Multi-point flue layout: SCR inlet / outlet NO x Analyzer, flue gas temperature sensor, online ammonia slip monitor; COAP inlet SO2, heavy metal, and dust concentration sensors; unit load, main steam flow, and economizer water temperature acquisition units; all data are synchronously uploaded to the collaborative controller.

[0076] 3. Cooperative Adaptive Control Method Load stratification judgment logic: The controller divides the unit output into low load zone (30%-50%), medium load zone (50%-80%), and high load zone (80%-100%). Low-load coordinated regulation: the economizer water bypass is activated to increase the SCR flue gas temperature, and the ammonia injection volume is dynamically adjusted in different zones; the COAP is simultaneously switched to the -20℃ cryogenic setting to enhance the adsorption of acidic pollutants by utilizing the escaped ammonia from the SCR, thus offsetting the decrease in SCR denitrification efficiency. High-load energy-saving control: SCR flue gas temperature is sufficient, precise low ammonia injection, COAP is switched to 20℃ shallow cooling mode to reduce heat pump power consumption, and only deep dust removal and heavy metal removal are performed; Closed-loop feedback correction: Real-time collection of total pollutant concentration at the outlet, and simultaneous optimization of four sets of parameters: ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle using an improved particle swarm optimization algorithm. Material recycling linkage: COAP saturated adsorbent desorbs acidic flue gas and recirculates it for SCR catalytic decomposition, reducing ammonia consumption and hazardous waste production.

[0077] See Figure 2The diagram shows the overall flue gas flow chart of the SCR and COAP coupled flue gas system. The economizer, three-way diversion valve, SCR reactor, bypass heat exchange flue, desulfurization tower, and COAP low-temperature adsorption device are arranged sequentially in the flue gas duct at the tail of the boiler. It is equipped with a DCS collaborative controller and multi-component online flue gas monitoring instruments. The cooling heat pump, ammonia injection fan, and bypass regulating valve are all connected to the collaborative control loop.

[0078] Figure 3 This is a partially enlarged view of the three-way flue gas diversion bypass heat exchange structure.

[0079] Figure 4 This is a hardware wiring diagram for a hierarchical collaborative adaptive control system. The left and bottom sides of the system house the monitoring unit, responsible for acquiring operating data and transmitting it to the control center. Specifically, this includes a NOx analyzer, flue gas temperature sensor, ammonia slip monitor, SO2 sensor, and load acquisition unit, connected in sequence. These devices send the collected emission concentration, temperature, and load information to the collaborative controller in real time. The "collaborative controller" in the center of the diagram is the decision-making center of the entire system. It receives real-time monitoring data from various sensors, performs internal logic calculations, generates control commands, and outputs them externally. The right and middle sides of the system house the actuators, responsible for implementing the control commands. Regulation cascade: The output signal of the co-controller is first transmitted to the economizer bypass regulating valve, and then sequentially drives the ammonia injection flow regulating valve and the COAP cooling heat pump.

[0080] Auxiliary linkage: The operating status signal of the COAP cooling heat pump is fed back to the ammonia injection flow regulating valve through the dashed loop, forming a cascade control for local fine-tuning.

[0081] Regeneration feedback: The adsorbent regeneration device at the bottom receives the heat pump command to work, and its operating status is also fed back to the collaborative controller through the dotted line, forming a closed-loop monitoring.

[0082] To ensure adjustment accuracy, the system has established a real-time status feedback mechanism. Monitoring data from the SO2 sensor is directly transmitted back to the collaborative controller, providing a basis for the collaborative control of acidic gases.

[0083] Figure 5 This is a flowchart of the full-load zone control logic algorithm. The system operation begins at the top with the "Unit Load and Flue Gas Temperature Acquisition" module, which is responsible for acquiring the current operating status parameters of the unit as the basis for subsequent branch decisions.

[0084] The acquired load signal is divided into three intervals for parallel processing, with each branch corresponding to a different control strategy: Low load range (30% to 50%): For low load conditions, perform the operation of "increasing the SCR inlet flue gas temperature" to ensure the activity of the denitrification system.

[0085] Medium load range (50% to 80%): This range implements composite control, including "zone fine-tuning ammonia injection", "COAP deep cooling mode" and "COAP shallow cooling mode".

[0086] High load range (80% to 100%): For high load conditions, an "emission concentration feedback correction" strategy is adopted to adjust the operating status based on real-time emission data.

[0087] The processing results of the three branches are finally converged in the "COAP Shallow Cool Mode" module. This module integrates and normalizes the running instructions of each branch, transforms the multi-condition logic into a unified execution standard, and finally sends it to the bottom "Actuator Output" module to drive the corresponding physical equipment to perform actions, thereby completing the entire control closed loop.

[0088] Figure 6 This is a structural diagram of the COAP adsorbent regeneration flue gas recirculation pipeline. The COAP adsorption chamber, located on the left side of the image, is the core container of the system. Multiple layers of activated carbon adsorption are horizontally arranged inside the chamber to adsorb pollutants in the flue gas. A temperature measuring point is located in the middle of the left side of the chamber to monitor its internal operating status, and an exhaust port is located at the top. The regeneration heater, located on the right side of the image, is a vertical pressure vessel. It is connected to the lower part of the COAP adsorption chamber via piping and is used to heat the desorbed substances to provide the energy required for desorption. The desorbed gas collection tank is located above the regeneration heater and is used to temporarily store the high-concentration gas desorbed from the adsorption chamber. The desorbed gas collection tank is connected to the recirculation fan via piping. Under the action of the fan, the gas is pressurized and transported through the pipe marked as the recirculation flue on the right. The end of the recirculation flue is clearly marked pointing to the SCR inlet, indicating that the acidic gas produced by desorption will be reintroduced into the front end of the denitrification system for co-treatment.

[0089] The complete implementation steps are as follows: 1. The unit load is collected in real time, and the controller automatically determines the load range; 2. Low load: Increase the SCR flue gas temperature by opening the economizer bypass, slightly increase the ammonia injection in the zone, and switch COAP to deep cooling mode; 3. High load: Close part of the economizer bypass, precisely control ammonia injection, and switch COAP to shallow cooling energy-saving mode; 4. Online monitoring of outlet emission concentrations, with the algorithm continuously adjusting all actuator parameters; 5. COAP periodic regeneration, desorbing acidic flue gas and refluxing it to the front end of SCR for secondary catalytic decomposition.

[0090] Example 2 like Figure 7As shown, the present invention also provides an electronic device 100 for implementing a flue gas purification coupled and coordinated control method; The electronic device 100 includes a memory 101, at least one processor 102, a computer program 103 stored in the memory 101 and executable on at least one processor 102, and at least one communication bus 104.

[0091] The memory 101 can be used to store the computer program 103. The processor 102 implements the steps of Embodiment 1 by running or executing the computer program stored in the memory 101 and calling the data stored in the memory 101.

[0092] The memory 101 may primarily include a program storage area and a data storage area. The program storage area may store the operating system, application programs required for at least one function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created based on the use of the electronic device 100 (such as audio data), etc. In addition, the memory 101 may include non-volatile memory, such as hard disk, RAM, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other non-volatile solid-state storage device.

[0093] At least one processor 102 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Processor 102 may be a microprocessor or any conventional processor. Processor 102 is the control center of electronic device 100, connecting various parts of electronic device 100 via various interfaces and lines.

[0094] The memory 101 in the electronic device 100 stores multiple instructions to implement a flue gas purification coupled and coordinated control method, and the processor 102 can execute multiple instructions to achieve the following: Acquire data on the unit load, SCR inlet flue gas temperature, and flue gas pollutant concentration of the thermal power unit. The flue gas pollutant concentration data includes at least the SCR inlet NOx concentration, the SCR outlet NOx concentration, and the COAP inlet SO2 concentration. Determine the load range based on the unit load; Based on the load range, the NOx concentration at the SCR inlet, the NOx concentration at the SCR outlet, the flue gas temperature at the SCR inlet, and the SO2 concentration at the COAP inlet, determine the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle. Based on the ammonia injection flow rate, an SCR ammonia injection quantity control command is generated; based on the bypass flue gas ratio, a flue gas diversion control command is generated; based on the COAP cooling temperature, a COAP cooling temperature control command is generated; based on the adsorbent regeneration cycle, an adsorbent regeneration control command is generated; and based on the load range, an escape ammonia diversion control command and an acid gas reflux control command are generated. The ammonia injection rate of the ammonia injection dilution blower is controlled according to the SCR ammonia injection rate control command. According to the flue gas diversion control command, the opening of the flue gas diversion three-way valve is controlled to adjust the ratio of flue gas entering the SCR reactor from the main flue and the bypass flue with heat exchange coils that converge into the COAP purification inlet. According to the escaped ammonia diversion control command, control the valve of the SCR outlet clean flue gas diversion branch pipe to divert the clean flue gas carrying escaped ammonia from the SCR outlet to the COAP adsorption chamber as an auxiliary adsorption agent. The COAP cooling temperature setting is controlled according to the COAP cooling temperature control command. The COAP adsorbent regeneration cycle is controlled according to the adsorbent regeneration control command. According to the acid gas reflux control command, the valve of the COAP desorption and regeneration outlet reflux pipeline is controlled to reflux the acid gas generated by COAP desorption and regeneration back to the secondary catalytic decomposition in the flue gas duct before SCR.

[0095] Example 3 If the modules / units integrated in the electronic device 100 are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, and read-only memory (ROM).

[0096] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0097] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0098] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0099] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0100] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for coupled and coordinated control of flue gas purification, characterized in that, include: Acquire data on the unit load, SCR inlet flue gas temperature, and flue gas pollutant concentration of the thermal power unit. The flue gas pollutant concentration data includes at least the SCR inlet NOx concentration, the SCR outlet NOx concentration, and the COAP inlet SO2 concentration. Determine the load range based on the unit load; Based on the load range, the NOx concentration at the SCR inlet, the NOx concentration at the SCR outlet, the flue gas temperature at the SCR inlet, and the SO2 concentration at the COAP inlet, determine the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle. Based on the ammonia injection flow rate, an SCR ammonia injection quantity control command is generated; based on the bypass flue gas ratio, a flue gas diversion control command is generated; based on the COAP cooling temperature, a COAP cooling temperature control command is generated; based on the adsorbent regeneration cycle, an adsorbent regeneration control command is generated; and based on the load range, an escape ammonia diversion control command and an acid gas reflux control command are generated. The ammonia injection rate of the ammonia injection dilution blower is controlled according to the SCR ammonia injection rate control command. According to the flue gas diversion control command, the opening of the flue gas diversion three-way valve is controlled to adjust the ratio of flue gas entering the SCR reactor from the main flue and the bypass flue with heat exchange coils that converge into the COAP purification inlet. According to the escaped ammonia diversion control command, control the valve of the SCR outlet clean flue gas diversion branch pipe to divert the clean flue gas carrying escaped ammonia from the SCR outlet to the COAP adsorption chamber as an auxiliary adsorption agent. The COAP cooling temperature setting is controlled according to the COAP cooling temperature control command. The COAP adsorbent regeneration cycle is controlled according to the adsorbent regeneration control command. According to the acid gas reflux control command, the valve of the COAP desorption and regeneration outlet reflux pipeline is controlled to reflux the acid gas generated by COAP desorption and regeneration back to the secondary catalytic decomposition in the flue gas duct before SCR.

2. The method according to claim 1, characterized in that, The load range is divided into low load range, medium load range or high load range based on the pre-set unit output. When the load range is a low load range, the SCR ammonia injection control command is a command to dynamically adjust and increase the ammonia injection amount by partitioning, the flue gas diversion control command is a command to open the economizer water bypass to increase the SCR inlet flue gas temperature, the COAP cooling temperature control command is a command to switch to the preset cryogenic setting, and the adsorbent regeneration control command is a command to extend the adsorbent regeneration cycle. When the load range is a high load range, the SCR ammonia injection quantity control command is a command for precise low ammonia injection, the flue gas diversion control command is a command to close a preset portion of the economizer water bypass, and the COAP cooling temperature control command is a command to switch to a preset shallow cooling mode. When the load range is the medium load range, the SCR ammonia injection control command, the flue gas diversion control command, and the COAP cooling temperature control command are all transition control commands, so that the SCR ammonia injection rate, economizer water bypass opening and COAP cooling temperature smoothly transition between preset shallow cooling and preset deep cooling.

3. The method according to claim 1, characterized in that, The flue gas pollutant concentration data also include SCR outlet ammonia escape, COAP inlet heavy metal concentration, COAP inlet dust concentration, unit main steam flow rate, and economizer outlet water temperature. The determination of ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle based on the load range, the SCR inlet NOx concentration, the SCR outlet NOx concentration, the SCR inlet flue gas temperature, and the COAP inlet SO2 concentration includes: Based on the load range, the NOx concentration at the SCR inlet, the NOx concentration at the SCR outlet, the flue gas temperature at the SCR inlet, the SO2 concentration at the COAP inlet, the ammonia slip at the SCR outlet, the heavy metal concentration at the COAP inlet, the dust concentration at the COAP inlet, the main steam flow rate of the unit, and the water temperature at the economizer outlet, an improved particle swarm optimization algorithm is used to synchronously optimize and output the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle.

4. The method according to claim 3, characterized in that, In the improved particle swarm optimization algorithm, the particle position vector includes four dimensions: the ammonia injection flow rate, the bypass flue gas ratio, the COAP cooling temperature, and the adsorbent regeneration cycle. The fitness function is a weighted sum of minimizing the total pollutant concentration at the outlet and minimizing the system energy consumption.

5. The method according to claim 4, characterized in that, Also includes: Real-time collection of total pollutant concentrations at the outlet, including the final emission concentrations of NOx, SO2, heavy metals, and dust; Based on the total pollutant concentration at the outlet, the fitness function of the improved particle swarm optimization algorithm is rolled over and corrected, and the ammonia injection flow rate, bypass flue gas ratio, COAP cooling temperature, and adsorbent regeneration cycle are re-output.

6. The method according to claim 1, characterized in that, The process of diverting the clean flue gas carrying escaped ammonia from the SCR outlet to the COAP adsorption chamber as an auxiliary adsorption agent includes: The clean flue gas from the SCR outlet is introduced into the COAP adsorption chamber through a branch pipe located at the SCR outlet. The escaped ammonia is used as an auxiliary adsorbent for COAP adsorption of acidic pollutants to enhance the adsorption of acidic pollutants.

7. The method according to claim 1, characterized in that, The step of recirculating the acidic gas generated by COAP desorption and regeneration to the SCR pre-flue for secondary catalytic decomposition includes: The acidic gas generated by the desorption of the COAP saturated adsorbent is transported to the SCR pre-flue through a reflux pipeline, where the acidic gas undergoes secondary catalytic decomposition under the action of the SCR catalyst.

8. The method according to claim 1, characterized in that, The COAP cooling temperature settings correspond to the COAP's built-in three-level adjustable cooling circuit, which includes a preset deep cooling setting, a 0°C cooling setting, and a preset shallow cooling setting. When controlling the COAP cooling temperature setting, a linkage power supply signal is simultaneously output to the cooling heat pump power supply, the ammonia injection dilution fan, and the economizer bypass regulating valve, so that the cooling heat pump, the ammonia injection dilution fan, and the economizer bypass regulating valve perform linkage power supply.

9. An electronic device, characterized in that, It includes a processor and a memory, the processor being used to execute a computer program stored in the memory to implement the flue gas purification coupled and coordinated control method as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one instruction, which, when executed by a processor, implements the flue gas purification coupled and coordinated control method as described in any one of claims 1 to 8.

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