Ammonia-process carbon capture system driven by waste heat of power plant and ammonia-process carbon capture method driven by waste heat of power plant

Abstract

The invention relates to the technical field of carbon capture and storage, and discloses an ammonia-process carbon capture system and method driven by waste heat of a power plant. Comprising a parameter monitoring module, a basic data acquisition module, a data analysis module, a waste heat matching regulation and control module, an ammonia regeneration optimization module, an ammonia escape control module, an online feedback module, a system energy efficiency evaluation module and a central control visualization module, the basic data acquisition module is responsible for constructing a digital reference of the system, the data analysis module outputs waste heat utilization efficiency, COcapture specific energy consumption and an ammonia escape control rate which are used for decision making, and the waste heat matching regulation and control module, the ammonia regeneration optimization module and the ammonia escape control module regulate system parameters according to calculation results. The on-line feedback module drives an on-site regulating valve, a variable frequency pump and an execution mechanism of a fan to act, the system energy efficiency evaluation module periodically generates a system comprehensive energy efficiency report, and the central control visualization module intensively displays the system state.

Description

Technical Field

[0001] This invention relates to the field of carbon capture and storage technology, specifically to an ammonia-based carbon capture system and method driven by waste heat from power plants. Background Technology

[0002] Traditional flue gas decarbonization technologies in thermal power plants mostly employ chemical absorption methods, but these generally suffer from two major bottlenecks: first, they rely on high-grade steam to drive the regeneration process, resulting in primary energy waste; second, the carbon capture system operates in isolation from the power plant's thermal system, failing to effectively utilize low-grade waste heat resources. Especially in actual coal-fired power plant operations, waste heat supply is significantly affected by unit load fluctuations, leading to poor stability of the regeneration heat source, easily causing a decline in carbon capture efficiency or forcing the use of fossil fuels for auxiliary heating, exacerbating carbon emission problems. Furthermore, existing technologies lack real-time monitoring and dynamic control methods for key energy efficiency indicators (such as waste heat utilization rate and unit capture energy consumption), making it difficult to achieve full-process optimization; ammonia escape control in ammonia-based systems often adopts fixed-condition strategies, which cannot adapt to changes in operating conditions, easily leading to excessive ammonia emissions or the risk of crystallization blockage. To address the shortcomings of existing technologies, this invention provides an ammonia-based carbon capture system and method driven by power plant waste heat. Summary of the Invention

[0003] (a) Technical problems to be solved

[0004] To address the shortcomings of existing technologies, this invention provides an ammonia-based carbon capture system and method driven by waste heat from power plants. It has the advantages of dynamic matching of waste heat supply and demand, real-time optimization of energy efficiency indicators, and intelligent control of ammonia escape. It solves the problems of low waste heat utilization efficiency, ambiguous energy consumption benchmarks, and difficulty in stable control of ammonia emissions in traditional carbon capture systems.

[0005] (II) Technical Solution

[0006] To achieve the above objectives, the present invention provides the following technical solution: an ammonia-based carbon capture system driven by waste heat from a power plant, comprising a parameter monitoring module, a basic data acquisition module, a data analysis module, a waste heat matching and control module, an ammonia regeneration optimization module, an ammonia escape control module, an online feedback module, a system energy efficiency assessment module, and a central control visualization module;

[0007] The parameter monitoring module is responsible for sensing the system's operating status in real time, collecting all key process variables and equipment parameters online, and providing a real-time data stream for the entire system.

[0008] The basic data acquisition module is responsible for building the system's digital benchmark by acquiring and integrating historical, physical, and design data from multiple sources, including DCS, physical property database, and design drawings.

[0009] The data analysis module receives monitored and collected data, incorporates thermodynamic and kinetic models for real-time calculation and analysis, and outputs waste heat utilization efficiency for decision-making. CO2 capture ratio energy consumption ammonia escape control rate ;

[0010] The waste heat matching and control module is based on the waste heat utilization efficiency output by the data analysis module. The valve opening of the waste heat medium leading to the regeneration tower is dynamically adjusted to achieve precise matching of waste heat supply and demand, and the backup heat source is automatically activated when the waste heat is insufficient.

[0011] The ammonia regeneration optimization module is based on the CO2 capture ratio energy consumption. The real-time calculation results are used to adjust key operating parameters such as the rich liquid circulation rate and the regeneration tower pressure through a dynamic optimization algorithm.

[0012] The ammonia escape control module is based on the ammonia escape control rate. Based on the calculation results, closed-loop control is implemented for the frequency of the washing liquid circulation pump and the regeneration temperature, while the ammonia volatilization coefficient is monitored. Actively prevent the risk of crystallization blockage;

[0013] The online feedback module receives instructions from the data analysis module, waste heat matching and control module, ammonia regeneration optimization module and ammonia escape control module, and immediately drives the actuators of the regulating valve, variable frequency pump and fan on site to operate.

[0014] The system energy efficiency assessment module integrates all operating data and calculation results to regularly generate the "Carbon Capture Energy Consumption Daily Report", "Ammonia Balance Sheet" and system comprehensive energy efficiency report;

[0015] The central control visualization module centrally displays all real-time data, calculated indicators, alarm information, equipment status, and control actions in a graphical and chart-like manner.

[0016] Preferably, the parameter monitoring module includes a waste heat parameter monitoring unit, a carbon capture process monitoring unit, and an equipment status monitoring unit.

[0017] Preferably, the waste heat parameter monitoring unit monitors the temperature, mass flow rate, component concentration, flow rate, and pressure of the low-grade waste heat from the power plant online;

[0018] The carbon capture process monitoring unit monitors online the concentration of ammonia-rich solution, carbon dioxide absorption rate, pH value at key points of the system, outlet temperature of the regeneration tower, liquid level of the regeneration tower, ammonia concentration at the outlet of the scrubber, and CO2 load of the lean solution.

[0019] The equipment status monitoring unit monitors the corrosion rate of the regeneration tower, pump / fan bearing vibration, pump and valve operating pressure difference, tube-side / shell-side pressure drop of key heat exchangers, fan power, and current / power consumption of the ammonia circulating pump online.

[0020] Preferably, the basic data acquisition module includes a waste heat basic data acquisition unit, a carbon capture medium data acquisition unit, and an equipment basic data acquisition unit; the data analysis module includes a waste heat utilization efficiency calculation unit, a CO2 capture specific energy consumption calculation unit, and an ammonia slip control rate calculation unit.

[0021] Preferably, the waste heat basic data acquisition unit is responsible for acquiring historical waste heat data of the power plant, heat loss coefficient of waste heat pipeline, seasonal change data of ambient temperature, stability index of waste heat source, future power plant load forecast data, and the period when waste heat can be utilized.

[0022] The carbon capture medium data acquisition unit is responsible for acquiring ammonia water physical property data, carbon dioxide diffusion coefficient in ammonia water, ammonia water surface tension and reaction kinetic constants.

[0023] The equipment basic data acquisition unit is responsible for obtaining the design volume of the regeneration tower, the material and design pressure resistance level of the regeneration tower, the specific surface area of ​​the ammonia scrubber packing, the design heat transfer coefficient and heat transfer area of ​​the key heat exchangers, the equipment investment cost, the operation and maintenance baseline cost, and the equipment design life and fatigue cycle.

[0024] Preferably, the waste heat utilization efficiency calculation unit calculates the waste heat utilization efficiency. The calculation formula is as follows:

[0025]

[0026] In the formula, Indicates the volumetric flow rate of the waste heat medium. Indicates the density of the waste heat medium. Indicates the specific heat capacity of the waste heat medium. , These represent the temperatures of waste heat entering / exiting the regenerator, respectively. Indicates waste heat utilization efficiency. This indicates the total waste heat output. Indicates the heat loss rate of the pipeline. This indicates the total amount of low-grade waste heat that can be utilized from power plants.

[0027] Preferably, the CO2 capture specific energy consumption calculation unit calculates the CO2 capture specific energy consumption. The calculation formula is as follows:

[0028]

[0029] In the formula, This indicates the energy consumption for waste heat-driven regeneration. This indicates the power consumption of auxiliary equipment such as pumps and fans. Indicates flue gas flow rate, This represents the total energy consumption of the system. This indicates the volume fraction of CO2 in the flue gas. Indicates CO2 absorption rate, This represents the CO2 density under standard conditions. This indicates the amount of CO2 captured per hour.

[0030] Preferably, the ammonia slip control rate calculation unit calculates the ammonia slip control rate. The calculation formula is as follows:

[0031]

[0032] In the formula, Indicates the flow rate of the washing liquid circulation. This indicates the ammonia mass concentration at the scrubber inlet. Indicates the specific surface area of ​​the filler. Indicates the ammonia absorption coefficient. This indicates the quality of ammonia recovered by the ammonia scrubber. This indicates the mass concentration of ammonia in ammonia-rich liquid. Indicates the volumetric flow rate of the rich liquid. Indicates the ammonia volatility coefficient. This indicates the total amount of ammonia volatilized during the regeneration process.

[0033] Preferably, the waste heat utilization efficiency calculation unit calculates the waste heat utilization efficiency. It is used to determine in real time whether low-grade waste heat is sufficient to cover regeneration heat demand. When the residual heat is less than 85%, an insufficient residual heat warning will be automatically activated, and the backup heat pump will be turned on in conjunction with it.

[0034] The CO2 capture ratio energy consumption calculation unit calculates the CO2 capture ratio energy consumption. Used for real-time benchmarking of DOE / IEA carbon capture energy consumption standards, when >2.0GJ t -1 Immediately trigger an energy consumption anomaly alarm;

[0035] The ammonia slip control rate calculation unit calculates the ammonia slip control rate. Used for closed-loop control of the washing liquid circulation pump frequency, when When the regeneration temperature is less than 98%, the system will automatically increase Vh or decrease the regeneration temperature setting.

[0036] A method for carbon capture using ammonia-based extraction driven by waste heat from a power plant includes the following steps:

[0037] Step 1: System Initialization and Basic Data Preloading: The system starts a self-test, calls and preloads all basic data from the basic data acquisition module, and establishes an accurate digital benchmark model for the entire system.

[0038] Step 2: Real-time data synchronization and monitoring: Real-time operating parameters of power plant waste heat, carbon capture process and equipment status are collected synchronously through the parameter monitoring module to provide a data stream for dynamic analysis;

[0039] Step 3: Real-time calculation of core energy efficiency and environmental protection indicators: The data analysis module calculates waste heat utilization efficiency based on real-time and basic data. CO2 capture ratio energy consumption The Dt value is calculated using the ammonia slip control rate calculation unit to evaluate the ammonia recovery effect.

[0040] Step 4: Waste Heat Driven Intelligent Regeneration Control: Waste Heat Matching and Control Module Receives... The values ​​are used to adjust parameters and issue early warnings, while the data is recorded as evidence for carbon emission verification.

[0041] Step 5: Optimization of the capture process based on specific energy consumption: Ammonia regeneration optimization module receives... The value determines whether to maintain the current operation or trigger an alarm, and generates optimization instructions;

[0042] Step Six: Closed-Loop Control and Risk Prevention of Ammonia Slip: The ammonia slip control module receives... The value determines whether to execute closed-loop control or adjust parameters;

[0043] Step 7: Comprehensive assessment of system energy efficiency and environmental compliance: The system energy efficiency assessment module integrates all operating data to generate a comprehensive system energy efficiency report and an "Ammonia Balance Sheet";

[0044] Step 8: Panoramic Visualization and Decision Support: The central control visualization module centrally displays all real-time parameters, calculated indicators, alarm information, control commands, and evaluation reports.

[0045] Compared with the prior art, the present invention provides an ammonia-based carbon capture system and method driven by waste heat from power plants, which has the following advantages:

[0046] 1. This invention calculates the waste heat utilization efficiency. It is used to determine in real time whether low-grade waste heat is sufficient to cover regeneration heat demand. When the heat utilization rate is less than 85%, an automatic warning for insufficient waste heat will be activated, and the backup heat pump will be turned on. This will be used as a KPI for the cascade utilization of heat energy in the power plant operation department and will be directly included in the monthly energy efficiency assessment. At the same time, it will provide evidence of the heat source for carbon emission reduction verification and avoid carbon emissions caused by additional fossil fuel heating.

[0047] 2. This invention calculates the CO2 capture specific energy consumption. Used for real-time benchmarking of DOE / IEA carbon capture energy consumption standards, when >2.0GJ t -1 It immediately triggers an energy consumption anomaly alarm, instructs operators to reduce the rich liquid circulation rate or increase the waste heat recovery rate, and generates a daily "Carbon Capture Energy Consumption Report", which is automatically uploaded to the group's carbon asset management platform for CCER revenue accounting, and provides energy saving assessment for technical transformation plans.

[0048] 3. This invention calculates the ammonia slip control rate. Used for closed-loop control of the washing liquid circulation pump frequency, when When the regeneration temperature is below 98%, the system automatically increases Vh or decreases the regeneration temperature setpoint to ensure that ammonia emissions from the chimney are ≤5mg Nm³. -3 It automatically generates an "Ammonia Balance Sheet" daily, accurate to the kg, for use in environmental tax calculation and discharge permit implementation reports, while also providing early warnings of the risk of oversaturation in the rich liquor: when When the pH value is continuously greater than 0.025, the system will automatically prompt you to add acid to adjust the pH or increase the cooling load to prevent ammonium bicarbonate from crystallizing and clogging the internal components of the tower. Attached Figure Description

[0049] Figure 1 This is a system flowchart of the present invention. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Please see Figure 1 A carbon capture system using ammonia-based carbon capture driven by waste heat from a power plant includes a parameter monitoring module, a basic data acquisition module, a data analysis module, a waste heat matching and control module, an ammonia regeneration optimization module, an ammonia escape control module, an online feedback module, a system energy efficiency assessment module, and a central control visualization module.

[0052] The parameter monitoring module is responsible for sensing the system's operating status in real time, collecting all key process variables and equipment parameters online, and providing a real-time data stream for the entire system.

[0053] The basic data acquisition module is responsible for building the system's digital baseline by acquiring and integrating historical, physical, and design data from multiple sources, including DCS, physical property database, and design drawings.

[0054] The data analysis module receives monitored and collected data, incorporates thermodynamic and kinetic models for real-time calculation and analysis, and outputs waste heat utilization efficiency for decision-making. CO2 capture ratio energy consumption ammonia escape control rate ;

[0055] The waste heat matching and control module is based on the waste heat utilization efficiency output by the data analysis module. The valve opening of the waste heat medium to the regeneration tower is dynamically adjusted to achieve precise matching of waste heat supply and demand, and the backup heat source is automatically started when the waste heat is insufficient to ensure the continuous and stable regeneration process.

[0056] The ammonia regeneration optimization module is based on the CO2 capture ratio energy consumption. The real-time calculation results are used to adjust key operating parameters such as the rich liquid circulation volume and the regeneration tower pressure through dynamic optimization algorithms to ensure that the system always operates in the low energy consumption range.

[0057] The ammonia slip control module is based on the ammonia slip control rate. Based on the calculation results, the frequency of the washing liquid circulation pump and the regeneration temperature are controlled in a closed loop. At the same time, the ammonia volatilization coefficient is monitored to proactively prevent the risk of crystallization blockage and ensure that ammonia emissions are better than environmental protection standards.

[0058] The online feedback module receives instructions from the data analysis module, waste heat matching and control module, ammonia regeneration optimization module and ammonia escape control module, and immediately drives the actuators of the regulating valves, variable frequency pumps and fans on site to act, forming a rapid closed loop of perception → analysis → decision → execution, ensuring the adaptive and stable operation of the system;

[0059] The system energy efficiency assessment module integrates all operational data and calculation results, and regularly generates the "Carbon Capture Energy Consumption Daily Report", "Ammonia Balance Sheet" and system comprehensive energy efficiency report, providing authoritative data support for internal KPI assessment, CCER revenue calculation, environmental tax declaration and technical transformation assessment.

[0060] The central control visualization module displays all real-time data, calculated indicators, alarm information, equipment status, and control actions in a graphical and chart-like manner, providing operators with an intuitive monitoring interface and providing management with a data dashboard for strategic decision-making.

[0061] The parameter monitoring module includes a waste heat parameter monitoring unit, a carbon capture process monitoring unit, and an equipment status monitoring unit.

[0062] The waste heat parameter monitoring unit monitors the temperature, mass flow rate, component concentration (such as CO2 / O2 concentration in flue gas), flow rate and pressure of low-grade waste heat (steam turbine exhaust / flue gas) of the power plant online through thermocouples, flow meters, pressure transmitters and flue gas analyzers, with a sampling frequency of 1 to 2 times / minute.

[0063] The carbon capture process monitoring unit monitors the concentration of ammonia-rich solution, carbon dioxide absorption rate, pH value at key points of the system, regeneration tower outlet temperature, regeneration tower liquid level, ammonia concentration at scrubber outlet, and CO2 load of lean solution online through a densitometer / conductivity meter, online gas analyzer, pH meter, temperature sensor, and concentration sensor.

[0064] The equipment condition monitoring unit monitors the corrosion rate of the regeneration tower, pump / fan bearing vibration, pump and valve operating pressure difference, tube-side / shell-side pressure drop of key heat exchangers, fan power, and current / power consumption of the ammonia circulation pump online through corrosion probes, vibration sensors, pressure sensors, and power meters.

[0065] The advantages are: the comprehensive and high-frequency real-time monitoring of waste heat, process, and equipment status, the accurate perception of key quality parameters (such as concentration and pH value), and the early diagnosis of equipment health (such as corrosion and vibration) provide a solid data foundation for intelligent system decision-making, ensure the stability, reliability, and predictability of the carbon capture process, and significantly reduce the risk of unplanned downtime.

[0066] The basic data acquisition module includes a waste heat basic data acquisition unit, a carbon capture medium data acquisition unit, and an equipment basic data acquisition unit; the data analysis module includes a waste heat utilization efficiency calculation unit, a CO2 capture specific energy consumption calculation unit, and an ammonia slip control rate calculation unit.

[0067] The waste heat basic data acquisition unit acquires historical data on waste heat from the power plant, heat loss coefficient of waste heat pipelines, seasonal variation data of ambient temperature, stability indicators of waste heat sources (such as fluctuation frequency and amplitude), future power plant load forecast data, and the available time periods of waste heat through the power plant's distributed control system (DCS) and historical database.

[0068] The carbon capture medium data acquisition unit acquires ammonia water property data (solubility, viscosity, gas-liquid equilibrium data, specific heat capacity at different temperatures), carbon dioxide diffusion coefficient in ammonia water, ammonia water surface tension, and reaction kinetic constants through chemical property databases (such as NIST) and laboratory test reports.

[0069] The equipment basic data acquisition unit obtains the design volume of the regeneration tower, the material and design pressure rating of the regeneration tower, the specific surface area of ​​the ammonia scrubber packing, the design heat transfer coefficient and heat transfer area of ​​the key heat exchangers, the equipment investment cost, the operation and maintenance baseline cost, and the equipment design life and fatigue cycle through the equipment manufacturer's data manual and engineering design scheme.

[0070] The advantages are: through the systematic integration of multi-source heterogeneous data, the complete acquisition of key physical property parameters and reaction kinetic constants, and the unified management of equipment life cycle cost and performance data, a high-precision digital twin model can be constructed, so that the system optimization and control strategy has a solid theoretical basis and boundary conditions, thereby achieving the beneficial effect of transitioning from experience-driven to data and model hybrid-driven.

[0071] Waste heat utilization efficiency calculation unit calculates waste heat utilization efficiency It is used to determine in real time whether low-grade waste heat is sufficient to cover regeneration heat demand, and its calculation formula is:

[0072]

[0073] In the formula, The waste heat medium volumetric flow rate is expressed in m³ / h. This indicates the density of the waste heat medium, in kg / m³. This indicates the specific heat capacity of the waste heat medium, expressed in kJ / (kg·℃). , These represent the temperatures of waste heat entering / exiting the regenerator, in °C. Indicates waste heat utilization efficiency. This represents the total waste heat output, expressed in kJ / h. This represents the heat loss rate of the pipeline (dimensionless, ranging from 0.03 to 0.05). This indicates the total amount of low-grade waste heat that can be utilized from the power plant, expressed in kJ / h.

[0074] The advantage is that it allows for the calculation of waste heat utilization efficiency. By introducing a pipeline heat loss coefficient for precise correction and a closed-loop management mechanism that directly links the calculation results with early warning, assessment, and carbon verification, the system not only achieves real-time quantification of waste heat utilization levels but also proactively ensures the stability of regenerated heat sources. At the same time, it provides key evidence of measurable, reportable, and verifiable (MRV) for the low-carbon attributes of the entire system.

[0075] The CO2 capture energy consumption calculation unit calculates the CO2 capture energy consumption. It is used for real-time benchmarking against the DOE / IEA carbon capture energy consumption benchmark, and its calculation formula is as follows:

[0076]

[0077] In the formula, This indicates the energy consumption for waste heat-driven regeneration (utilizing only low-grade waste heat, without high-grade steam). This indicates the power consumption of auxiliary equipment such as pumps and fans, in kJ / h. This indicates the flue gas flow rate, measured in Nm³ / h. This represents the total energy consumption of the system, expressed in kJ / h. This indicates the volume fraction of CO2 in flue gas (unit: dimensionless). This indicates the CO2 absorption rate (unit: dimensionless, design value ≥90%). This indicates the density of CO2 under standard conditions, in units of 1.977 kg / Nm³. This indicates the amount of CO2 captured per hour, expressed in t / h.

[0078] The advantage is that it allows for the calculation of CO2 capture specific energy consumption. The scientific approach of unifying waste heat and electricity consumption accounting, the management method of real-time benchmarking against international authoritative energy consumption benchmarks (such as DOE / IEA), and the value mining mechanism of directly linking energy consumption data to CCER revenue accounting and technological transformation assessment have achieved the beneficial effect of transforming the abstract concept of "energy consumption" into specific operating costs and carbon asset revenue, driving the system to operate continuously in the optimal economic range, and providing core data support for corporate carbon asset management.

[0079] The ammonia slip control rate calculation unit calculates the ammonia slip control rate. The formula for calculating the frequency of the washing liquid circulation pump used in closed-loop control is as follows:

[0080]

[0081] In the formula, This indicates the washing liquid circulation flow rate, in m³ / h. This indicates the ammonia concentration at the scrubber inlet, in kg / m³. This indicates the specific surface area of ​​the filler, in m² / m³. The ammonia absorption coefficient is expressed in kg / (m²·h), with an experimental calibration range of 0.85-0.95. This indicates the mass of ammonia recovered by the ammonia scrubber, in kg / h. This indicates the mass concentration of ammonia in ammonia-rich liquid, expressed in kg / m³. This indicates the volumetric flow rate of the rich liquid, in m³ / h. This represents the ammonia volatilization coefficient (unit: dimensionless, temperature and pH related, value range: 0.015-0.025). This indicates the total ammonia volatilization during the regeneration process, expressed in kg / h.

[0082] The advantages are: through the mechanism model built on the principle of mass transfer and reaction kinetics, the control rate and key operating variables (circulation rate, temperature) form a closed-loop instant response mechanism, and the predictive maintenance strategy of monitoring the volatility coefficient to provide early warning of crystallization risk, the beneficial effects of achieving ultra-low ammonia emissions to meet the most stringent environmental protection standards are achieved, while effectively controlling absorbent loss and preventing equipment blockage, thus taking into account both environmental benefits and operational economy.

[0083] Waste heat utilization efficiency calculation unit calculates waste heat utilization efficiency It is used to determine in real time whether low-grade waste heat is sufficient to cover regeneration heat demand. When the heat utilization rate is less than 85%, an automatic warning for insufficient waste heat will be activated, and the backup heat pump will be turned on. This will be used as a KPI for the cascade utilization of heat energy in the power plant operation department and will be directly included in the monthly energy efficiency assessment. At the same time, it will provide evidence of the heat source for carbon emission reduction verification and avoid carbon emissions caused by additional fossil fuel heating.

[0084] The CO2 capture energy consumption calculation unit calculates the CO2 capture energy consumption. Used for real-time benchmarking of DOE / IEA carbon capture energy consumption standards, when >2.0GJ t -1 It immediately triggers an energy consumption anomaly alarm, instructs operators to reduce the rich liquid circulation rate or increase the waste heat recovery rate, and generates a daily "Carbon Capture Energy Consumption Report", which is automatically uploaded to the group's carbon asset management platform for CCER revenue accounting, and provides energy saving assessment for technical transformation plans.

[0085] The ammonia slip control rate calculation unit calculates the ammonia slip control rate. Used for closed-loop control of the washing liquid circulation pump frequency, when When the regeneration temperature is below 98%, the system automatically increases Vh or decreases the regeneration temperature setpoint to ensure that ammonia emissions from the chimney are ≤5mg Nm³. -3 It automatically generates an "Ammonia Balance Sheet" daily, accurate to the kg, for use in environmental tax calculation and discharge permit implementation reports, while also providing early warnings of the risk of oversaturation in the rich liquor: when When the pH value is continuously greater than 0.025, the system will automatically prompt you to add acid to adjust the pH or increase the cooling load to prevent ammonium bicarbonate from crystallizing and clogging the internal components of the tower.

[0086] A method for carbon capture using ammonia-based extraction driven by waste heat from a power plant includes the following steps:

[0087] Step 1: System Initialization and Basic Data Preloading: The system starts a self-test, calls and preloads all basic data from the basic data acquisition module, including historical data of waste heat from the power plant, physical property data of ammonia water, equipment design parameters and cost data, to establish an accurate digital benchmark model for the entire system;

[0088] Step 2: Real-time data synchronization and monitoring: Through each unit of the parameter monitoring module, real-time operating parameters of power plant waste heat, carbon capture process and equipment status are collected synchronously at a frequency of 1 to 2 times / minute, providing a data stream for dynamic analysis;

[0089] Step 3: Real-time Calculation of Core Energy Efficiency and Environmental Indicators: Based on real-time and basic data, the data analysis module executes three core calculations in parallel: waste heat utilization efficiency calculation unit calculation... Value, assess waste heat sufficiency; CO2 capture ratio energy consumption calculation unit calculates Value, benchmarked against energy consumption standards; ammonia slip control rate calculation unit calculates. Values ​​are used to evaluate the ammonia recovery effect;

[0090] Step 4: Waste Heat Driven Intelligent Regeneration Control: Waste Heat Matching and Control Module Receives... Value, when If ≥85%, then the waste heat is allocated to the regeneration tower according to the optimal strategy; if If the emissions are less than 85%, an early warning will be automatically triggered and the backup heat pump will be activated to ensure the stability of the regenerated heat source. At the same time, the data will be recorded as evidence for carbon emission verification.

[0091] Step 5: Optimization of the capture process based on specific energy consumption: Ammonia regeneration optimization module receives... Value, when ≤2.0GJ / t, the system maintains its current operation; when If the energy consumption exceeds 2.0 GJ / t, an alarm will be automatically triggered, and optimization instructions will be generated to guide the operator or automatic adjustment system to reduce the rich liquid circulation volume or increase the waste heat recovery rate. At the same time, a "Carbon Capture Energy Consumption Daily Report" will be generated for CCER accounting.

[0092] Step Six: Closed-Loop Control and Risk Prevention of Ammonia Slip: The ammonia slip control module receives... Value, when If the ammonia evaporation rate is less than 98%, closed-loop control will be automatically executed, increasing the frequency (Vh) of the washing liquid circulation pump or decreasing the setpoint of the regeneration tower temperature. Simultaneously, the module continuously monitors the ammonia volatilization coefficient. When the pH value is continuously above 0.025, the system will automatically prompt you to add acid to adjust the pH or increase the cooling load to prevent the risk of ammonium bicarbonate crystallization and blockage.

[0093] Step 7: Comprehensive assessment of system energy efficiency and environmental compliance: The system energy efficiency assessment module integrates all operating data to generate a comprehensive system energy efficiency report and an "Ammonia Balance Sheet," accurately calculating ammonia consumption and carbon emissions. The report is directly used for internal energy efficiency assessment, environmental tax calculation, and pollution discharge permit implementation reports.

[0094] Step 8: Panoramic Visualization and Decision Support: The central control visualization module centrally displays all real-time parameters, calculated indicators, alarm information, control commands, and evaluation reports, providing operators with a human-machine interface and data decision support for the power plant's carbon asset management and long-term technological upgrades.

[0095] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An ammonia-based carbon capture system driven by waste heat from a power plant, characterized in that, It includes a parameter monitoring module, a basic data acquisition module, a data analysis module, a waste heat matching and control module, an ammonia regeneration optimization module, an ammonia escape control module, an online feedback module, a system energy efficiency assessment module, and a central control visualization module; The parameter monitoring module is responsible for sensing the system's operating status in real time, collecting all key process variables and equipment parameters online, and providing a real-time data stream for the entire system. The basic data acquisition module is responsible for building the system's digital benchmark by acquiring and integrating historical, physical, and design data from multiple sources, including DCS, physical property database, and design drawings. The data analysis module receives monitored and collected data, incorporates thermodynamic and kinetic models for real-time calculation and analysis, and outputs waste heat utilization efficiency for decision-making. CO2 capture ratio energy consumption ammonia escape control rate ; The waste heat matching and control module is based on the waste heat utilization efficiency output by the data analysis module. The valve opening of the waste heat medium leading to the regeneration tower is dynamically adjusted to achieve precise matching of waste heat supply and demand, and the backup heat source is automatically activated when the waste heat is insufficient. The ammonia regeneration optimization module is based on the CO2 capture ratio energy consumption. The real-time calculation results are used to adjust key operating parameters such as the rich liquid circulation rate and the regeneration tower pressure through a dynamic optimization algorithm. The ammonia escape control module is based on the ammonia escape control rate. Based on the calculation results, closed-loop control is implemented for the frequency of the washing liquid circulation pump and the regeneration temperature, while the ammonia volatilization coefficient is monitored. Actively prevent the risk of crystallization blockage; The online feedback module receives instructions from the data analysis module, waste heat matching and control module, ammonia regeneration optimization module and ammonia escape control module, and immediately drives the actuators of the regulating valve, variable frequency pump and fan on site to operate. The system energy efficiency assessment module integrates all operating data and calculation results to regularly generate the "Carbon Capture Energy Consumption Daily Report", "Ammonia Balance Sheet" and system comprehensive energy efficiency report; The central control visualization module centrally displays all real-time data, calculated indicators, alarm information, equipment status, and control actions in a graphical and chart-like manner.

2. The ammonia-based carbon capture system driven by waste heat from a power plant according to claim 1, characterized in that: The parameter monitoring module includes a waste heat parameter monitoring unit, a carbon capture process monitoring unit, and an equipment status monitoring unit.

3. The ammonia-based carbon capture system driven by waste heat from a power plant according to claim 2, characterized in that: The waste heat parameter monitoring unit monitors the temperature, mass flow rate, component concentration, flow rate, and pressure of the low-grade waste heat from the power plant online. The carbon capture process monitoring unit monitors online the concentration of ammonia-rich solution, carbon dioxide absorption rate, pH value at key points of the system, outlet temperature of the regeneration tower, liquid level of the regeneration tower, ammonia concentration at the outlet of the scrubber, and CO2 load of the lean solution. The equipment status monitoring unit monitors the corrosion rate of the regeneration tower, pump / fan bearing vibration, pump and valve operating pressure difference, tube-side / shell-side pressure drop of key heat exchangers, fan power, and current / power consumption of the ammonia circulating pump online.

4. The ammonia-based carbon capture system driven by waste heat from a power plant according to claim 1, characterized in that: The basic data acquisition module includes a waste heat basic data acquisition unit, a carbon capture medium data acquisition unit, and an equipment basic data acquisition unit; the data analysis module includes a waste heat utilization efficiency calculation unit, a CO2 capture ratio energy consumption calculation unit, and an ammonia slip control rate calculation unit.

5. The ammonia-based carbon capture system driven by waste heat from a power plant according to claim 4, characterized in that: The waste heat basic data acquisition unit is responsible for acquiring historical waste heat data of the power plant, heat loss coefficient of waste heat pipeline, seasonal change data of ambient temperature, stability index of waste heat source, future power plant load forecast data, and the period when waste heat can be utilized. The carbon capture medium data acquisition unit is responsible for acquiring ammonia water physical property data, carbon dioxide diffusion coefficient in ammonia water, ammonia water surface tension and reaction kinetic constants; The equipment basic data acquisition unit is responsible for obtaining the design volume of the regeneration tower, the material and design pressure resistance level of the regeneration tower, the specific surface area of ​​the ammonia scrubber packing, the design heat transfer coefficient and heat transfer area of ​​the key heat exchangers, the equipment investment cost, the operation and maintenance baseline cost, and the equipment design life and fatigue cycle.

6. The ammonia-based carbon capture system driven by waste heat from a power plant according to claim 4, characterized in that: The waste heat utilization efficiency calculation unit calculates the waste heat utilization efficiency. The calculation formula is as follows: In the formula, Indicates the volumetric flow rate of the waste heat medium. Indicates the density of the waste heat medium. Indicates the specific heat capacity of the waste heat medium. , These represent the temperatures at which waste heat enters / exits the regenerator, respectively. Indicates waste heat utilization efficiency. This indicates the total waste heat output. Indicates the heat loss rate of the pipeline. This indicates the total amount of low-grade waste heat that can be utilized from power plants.

7. The ammonia-based carbon capture system driven by waste heat from a power plant according to claim 4, characterized in that: The CO2 capture ratio energy consumption calculation unit calculates the CO2 capture ratio energy consumption. The calculation formula is as follows: In the formula, This indicates the energy consumption for waste heat-driven regeneration. This indicates the power consumption of auxiliary equipment such as pumps and fans. Indicates flue gas flow rate, This represents the total energy consumption of the system. This indicates the volume fraction of CO2 in the flue gas. Indicates CO2 absorption rate, This represents the CO2 density under standard conditions. This indicates the amount of CO2 captured per hour.

8. The ammonia-based carbon capture system driven by waste heat from a power plant according to claim 4, characterized in that: The ammonia slip control rate calculation unit calculates the ammonia slip control rate. The calculation formula is as follows: In the formula, Indicates the flow rate of the washing liquid circulation. This indicates the ammonia mass concentration at the scrubber inlet. Indicates the specific surface area of ​​the filler. Indicates the ammonia absorption coefficient. This indicates the quality of ammonia recovered by the ammonia scrubber. This indicates the mass concentration of ammonia in ammonia-rich liquid. Indicates the volumetric flow rate of the rich liquid. Indicates the ammonia volatility coefficient. This indicates the total amount of ammonia volatilized during the regeneration process.

9. A carbon capture system using ammonia-based carbon capture driven by waste heat from a power plant, as described in claim 4, is characterized in that: The waste heat utilization efficiency calculation unit calculates the waste heat utilization efficiency. It is used to determine in real time whether low-grade waste heat is sufficient to cover regeneration heat demand. When the residual heat is less than 85%, an insufficient residual heat warning will be automatically activated, and the backup heat pump will be turned on in conjunction with it. The CO2 capture ratio energy consumption calculation unit calculates the CO2 capture ratio energy consumption. Used for real-time benchmarking of DOE / IEA carbon capture energy consumption standards, when >2.0GJ t -1 Immediately trigger an energy consumption anomaly alarm; The ammonia slip control rate calculation unit calculates the ammonia slip control rate. Used for closed-loop control of the washing liquid circulation pump frequency, when When the regeneration temperature is less than 98%, the system will automatically increase Vh or decrease the regeneration temperature setting.

10. A method for ammonia-based carbon capture driven by waste heat from a power plant, characterized in that, Includes the following steps: Step 1: System Initialization and Basic Data Preloading: The system starts a self-test, calls and preloads all basic data from the basic data acquisition module, and establishes an accurate digital benchmark model for the entire system. Step 2: Real-time data synchronization and monitoring: Real-time operating parameters of power plant waste heat, carbon capture process and equipment status are collected synchronously through the parameter monitoring module to provide a data stream for dynamic analysis; Step 3: Real-time calculation of core energy efficiency and environmental protection indicators: The data analysis module calculates waste heat utilization efficiency based on real-time and basic data. CO2 capture ratio energy consumption The Dt value is calculated using the ammonia slip control rate calculation unit to evaluate the ammonia recovery effect. Step 4: Waste Heat Driven Intelligent Regeneration Control: Waste Heat Matching and Control Module Receives... The values ​​are used to adjust parameters and issue early warnings, while the data is recorded as evidence for carbon emission verification. Step 5: Optimization of the capture process based on specific energy consumption: Ammonia regeneration optimization module receives... The value determines whether to maintain the current operation or trigger an alarm, and generates optimization instructions; Step Six: Closed-Loop Control and Risk Prevention of Ammonia Slip: The ammonia slip control module receives... The value determines whether to execute closed-loop control or adjust parameters; Step 7: Comprehensive assessment of system energy efficiency and environmental compliance: The system energy efficiency assessment module integrates all operating data to generate a comprehensive system energy efficiency report and an "Ammonia Balance Sheet"; Step 8: Panoramic Visualization and Decision Support: The central control visualization module centrally displays all real-time parameters, calculated indicators, alarm information, control commands, and evaluation reports.

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