A method for calibrating the emission allowance under fuel composition fluctuation

Abstract

This invention discloses a method for calibrating emission permits under fuel composition fluctuations. The invention relates to the field of industrial furnace and kiln pollutant emission control technology and includes the following steps: 1) Data acquisition step: During the operation of the industrial furnace and kiln, the actual elemental composition data of the currently used fuel is collected in real time or periodically through a deployed fuel composition monitoring device. This emission permit calibration method under fuel composition fluctuations establishes a closed-loop feedback mechanism between real-time fuel composition monitoring and dynamic calibration factors, transforming the traditional static accounting system into a dynamic calibration system capable of responding to changes in fuel characteristics. This method dynamically corrects the baseline flue gas volume and performance value based on actual elemental composition data, solving the problem of inaccurate calculations in fixed parameter systems when fuel composition fluctuates, and effectively improving the accuracy and reliability of emission permit calculations.

Description

Technical Field

[0001] This invention relates to the field of industrial furnace and kiln pollutant emission control technology, specifically a method for calibrating emission permit quantities under fuel composition fluctuations. Background Technology

[0002] In the current industrial furnace and kiln pollutant discharge permit accounting system, the calculation method based on baseline exhaust volume and fixed performance values ​​is widely used for equipment such as heating furnaces, heat treatment furnaces, and drying furnaces. This method calculates the baseline flue gas volume using theoretical formulas based on fuel type and calorific value, and then derives the pollutant emission performance value per unit of fuel by combining national and local pollutant emission standards, such as concentration limits for particulate matter, sulfur dioxide, and nitrogen oxides. Finally, the permitted emission volume is determined based on fuel consumption. Existing technology relies on the stability of fuel calorific value and assumes a fixed fuel composition, thus presupposing the certainty of the baseline flue gas volume and performance value. However, in actual industrial production, fuel sources are diverse and compositions are complex; their calorific value and elemental composition, such as sulfur and ash content, often fluctuate, causing the actual flue gas emission volume to deviate from the theoretical baseline value, and the performance value cannot accurately reflect the true emission level. This fixed-parameter method cannot dynamically calibrate the discharge permit when fuel composition fluctuates, resulting in a significant error between the calculated result and the actual emission volume. This may expose enterprises to the risk of exceeding emission standards and weaken the accuracy and fairness of environmental supervision. Therefore, there is an urgent need to develop a method that can adapt to fluctuations in fuel composition and calibrate emission permits in real time, in order to solve the core defect of inaccurate calculations caused by the reliance on fixed parameters in existing technologies. Summary of the Invention

[0003] The purpose of this invention is to provide a method for calibrating emission permits under fuel composition fluctuations, so as to solve the problems mentioned in the background art.

[0004] To address the aforementioned technical problems, this invention provides the following technical solution: a method for calibrating emission permits under fuel composition fluctuations, applied to an industrial furnace pollutant emission permit calculation system. The system determines a baseline flue gas volume based on fuel type and calorific value through theoretical calculations, derives a fixed performance value by combining pollutant emission concentration standards, and finally determines the permitted emission volume based on fuel consumption. The method is characterized by introducing a real-time fuel composition monitoring and dynamic correction mechanism to solve the problem of inaccurate baseline flue gas volume and performance value caused by fuel composition fluctuations; it includes the following steps:

[0005] 1) Data acquisition steps: During the operation of industrial furnaces and kilns, the actual elemental composition data of the fuel currently used is collected in real time or periodically through the deployed fuel composition monitoring device; the actual elemental composition data includes at least the carbon content, hydrogen content, oxygen content, sulfur content, nitrogen content, as-received ash content, and as-received moisture content;

[0006] 2) Dynamic calculation step: Based on the actual elemental composition data obtained in step 1), combined with the theoretical flue gas volume calculation formula corresponding to the fuel type and the preset excess air coefficient, the actual benchmark flue gas volume corresponding to the current fuel is dynamically calculated; the theoretical flue gas volume calculation formula is the original formula used in the accounting system to determine the benchmark flue gas volume, and the preset excess air coefficient is selected as a fixed value according to the fuel type;

[0007] 3) Calibration factor generation step: Compare the actual reference flue gas volume calculated in step 2) with the fixed reference flue gas volume preset in the accounting system to generate a dynamic calibration factor; the dynamic calibration factor is the ratio of the actual reference flue gas volume to the fixed reference flue gas volume.

[0008] 4) Performance value adjustment step: Using the dynamic calibration factor generated in step 3), the fixed performance value in the accounting system is corrected to obtain the calibrated performance value; the correction is achieved by multiplying the fixed performance value by the dynamic calibration factor;

[0009] 5) Permit Quantity Calculation Step: Based on the calibration performance value obtained in step 4), and combined with the fuel consumption of industrial furnaces and kilns, recalculate the permitted pollutant emissions; the fuel consumption is the actual maximum value or design consumption of the previous three years;

[0010] Through the above steps, dynamic calibration of the discharge permit amount can be achieved as fuel composition fluctuates, thereby improving the accuracy of accounting and the fairness of supervision.

[0011] Furthermore, the fuel composition monitoring device mentioned in step 1) includes at least one of an online industrial analyzer and an online chromatograph; the online industrial analyzer is used for component monitoring of solid fuels, and the online chromatograph is used for component monitoring of gaseous fuels; the acquisition frequency of the actual elemental composition data is determined according to the fuel batch replacement cycle or operating time interval to ensure that the data represents the current fuel state.

[0012] Furthermore, the process of dynamically calculating the actual baseline flue gas volume described in step 2) specifically includes:

[0013] Identify the current fuel type, including solid fuel, liquid fuel, coal gas, or natural gas;

[0014] Based on the fuel type, the corresponding theoretical flue gas volume calculation formula and excess air coefficient are invoked; the excess air coefficient is a fixed value.

[0015] Input the actual elemental composition data into the formula to calculate the actual baseline flue gas volume.

[0016] Furthermore, the generation of the dynamic calibration factor in step 3) further includes:

[0017] The preset fixed reference flue gas volume is determined through theoretical calculations based on the fuel's design calorific value or average calorific value.

[0018] The calculation of the dynamic calibration factor is performed automatically each time the fuel composition data is updated;

[0019] When the dynamic calibration factor exceeds the preset range, an alarm is triggered to prompt manual review or system adjustment.

[0020] Furthermore, the performance value adjustment mentioned in step 4) specifically includes:

[0021] The fixed performance value is obtained by querying the performance value table of the accounting system, which is preset based on fuel calorific value and pollutant type.

[0022] The calibration performance value is calculated by multiplying a fixed performance value by a dynamic calibration factor;

[0023] The calibration performance values ​​are applied to pollutant types, including particulate matter, sulfur dioxide, and nitrogen oxides.

[0024] Furthermore, the license quantity calculation described in step 5) further includes:

[0025] Fuel consumption is determined based on the maximum actual fuel consumption over the previous three years. If the actual fuel consumption is less than one year or exceeds the design consumption, the design consumption shall be used.

[0026] Permitted emissions are calculated by multiplying fuel consumption by the calibration performance value and then multiplying by a unit conversion factor.

[0027] The accounting results are used for environmental regulatory reports, pollution discharge permit renewals, or enterprise emission management.

[0028] Furthermore, the method also includes a data verification step, performed after step 1) and before step 2); the data verification step includes:

[0029] The actual elemental composition data collected is checked for reasonableness, and outliers are removed;

[0030] The accuracy of online monitoring data was verified through laboratory sampling analysis.

[0031] When the data deviation exceeds the threshold, the monitoring device is automatically calibrated or switched to a backup data source.

[0032] Furthermore, the method is integrated into a digital supervision platform to achieve automated execution; the platform includes:

[0033] The data acquisition module is used to connect to the fuel composition monitoring device and acquire real-time data;

[0034] The calculation module is used to perform dynamic calculations and generate calibration factors;

[0035] The output module is used to generate calibrated emission permit reports and transmit them to the regulatory system.

[0036] Furthermore, the method is applicable to a variety of industrial furnaces, including heating furnaces, heat treatment furnaces, and drying furnaces; the fuel types cover solid fuels, liquid fuels, coal gas, and natural gas; and the pollutants include particulate matter, sulfur dioxide, and nitrogen oxides.

[0037] Furthermore, the method achieves continuous optimization through closed-loop control; specifically, it includes:

[0038] Regularly compare the calibrated permitted emissions with actual emission monitoring data to evaluate the calibration effectiveness;

[0039] Based on the assessment results, adjust the parameters of the fuel composition monitoring device or update the theoretical calculation formula;

[0040] Establish a historical database for trend analysis and predictive model training to further improve calibration accuracy.

[0041] This invention provides a method for calibrating emission permit levels under fuel composition fluctuations. It has the following beneficial effects:

[0042] This method for calibrating emission permits under fuel composition fluctuations transforms the traditional static accounting system into a dynamic calibration system capable of responding to changes in fuel characteristics by establishing a closed-loop feedback mechanism for real-time monitoring of fuel composition and dynamic calibration factors. Based on actual elemental composition data, this method dynamically corrects the baseline flue gas volume and performance values, solving the problem of inaccurate calculations in fixed-parameter systems when fuel composition fluctuates, and effectively improving the accuracy and reliability of emission permit calculations.

[0043] This method for calibrating emission permits under fluctuating fuel composition constructs a fully automated system from data acquisition and dynamic calculation to result output, achieving unified calibration for multiple fuel types and pollutant categories. Through closed-loop control and continuous optimization mechanisms, the system can adapt to changes in fuel characteristics and continuously optimize calibration accuracy, enhancing the targeting and fairness of environmental supervision and providing technical support for precise enterprise management and scientific decision-making by regulatory authorities. Attached Figure Description

[0044] Figure 1 This is a schematic flowchart of a method for calibrating emission permit quantities under fuel composition fluctuations according to the present invention.

[0045] Figure 2 This is a data flow diagram of a method for calibrating emission permit quantities under fuel composition fluctuations according to the present invention.

[0046] Figure 3 This diagram illustrates the anomaly handling mechanism of a method for calibrating emission permit quantities under fuel composition fluctuations according to the present invention. Detailed Implementation

[0047] 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.

[0048] Please see Figures 1 to 3 This invention provides a technical solution: a method for calibrating emission permits under fuel composition fluctuations, applied to an industrial furnace pollutant emission permit calculation system. The system determines a baseline flue gas volume based on fuel type and calorific value through theoretical calculations, derives a fixed performance value by combining pollutant emission concentration standards, and finally determines the permitted emission volume based on fuel consumption. The method is characterized by introducing a real-time fuel composition monitoring and dynamic correction mechanism to solve the problem of inaccurate baseline flue gas volume and performance value caused by fuel composition fluctuations; it includes the following steps:

[0049] 1) Data acquisition steps: During the operation of industrial furnaces and kilns, the actual elemental composition data of the fuel currently used is collected in real time or periodically through the deployed fuel composition monitoring device; the actual elemental composition data includes at least the carbon content, hydrogen content, oxygen content, sulfur content, nitrogen content, as-received ash content, and as-received moisture content;

[0050] 2) Dynamic calculation step: Based on the actual elemental composition data obtained in step 1), combined with the theoretical flue gas volume calculation formula corresponding to the fuel type and the preset excess air coefficient, the actual benchmark flue gas volume corresponding to the current fuel is dynamically calculated;

[0051] It should be further explained that the process of dynamically calculating the actual baseline flue gas volume in step 2) specifically includes:

[0052] The theoretical flue gas volume calculation formula corresponding to fuel type is a well-known elemental analysis-based calculation model in the field of industrial furnace pollutant emission accounting, and its specific form is as follows:

[0053] Formulas for calculating the theoretical flue gas volume of solid fuels, such as coal and coke:

[0054] In the formula: V y,sThe actual baseline flue gas volume for solid fuel; C, H, S, and O represent the carbon, hydrogen, sulfur, and oxygen content of the fuel collected in step 1), i.e., mass fractions; 8.89, 26.57, and 3.33 are the coefficients for the corresponding gases generated by the combustion of elements, based on molar volume conversion under standard conditions; 0.21 is the oxygen volume fraction in the air, and 0.79 is the nitrogen gas integral in the air.

[0055] Formulas for calculating the theoretical flue gas volume of liquid fuels, such as heavy oil and diesel:

[0056] In the formula: V y,l The actual baseline flue gas volume for liquid fuel; C, H, S, and O have the same meanings as for solid fuel; W is the received baseline moisture content collected in step 1); 0.0124 is the correction factor for oxygen consumption due to moisture evaporation.

[0057] Formula for calculating the theoretical flue gas volume of coal gas, such as blast furnace gas and coke oven gas:

[0058] In the formula: V y,g1 The actual baseline flue gas volume for coal gas; CO, H2, H2S, CH4, and C2H4 represent the volume fractions of the corresponding components in the coal gas, collected by an online chromatograph in step 1); other hydrocarbon components in the coal gas, such as C3H8, are represented by "nC". n H m The calculation is based on "n times the volume factor"; O2 is the volume fraction of oxygen in the coal gas.

[0059] Natural gas is mainly composed of CH4. The theoretical flue gas volume calculation formula is as follows:

[0060] In the formula: V y,g2 The actual baseline flue gas volume for natural gas is represented by C2H6, which represents the volume fraction of ethane in natural gas. The meanings of other parameters are the same as those for coal gas. The volume fraction of CH4 in natural gas is usually ≥90%, which is confirmed by online chromatograph.

[0061] The theoretical flue gas volume calculation formula is the original formula used in the accounting system to determine the baseline flue gas volume, and the preset excess air coefficient is selected as a fixed value according to the fuel type.

[0062] It should be further explained that the fixed value of the excess air coefficient is determined based on the "Limits of Excess Air Coefficient for Industrial Furnace Combustion Systems" in GB / T 13271-2022 "Emission Standard of Air Pollutants for Boilers" and industry engineering practices. The specific values ​​and basis are as follows:

[0063] Solid fuels: The excess air coefficient is taken as 1.5, based on the fact that solid fuels, such as coal, have uneven particle size and large differences in volatile matter release during combustion, requiring a higher excess air to ensure complete combustion, and meeting the requirement of "excess air coefficient ≤ 1.6" in GB / T 13271-2022;

[0064] Liquid fuels: The excess air coefficient is taken as 1.2, based on the fact that liquid fuels, such as heavy oil, have high atomization and combustion efficiency, and the excess air requirement is lower than that of solid fuels, which meets the requirement of "for chamber combustion furnaces, i.e., liquid fuel excess air coefficient ≤ 1.3" in GB / T 13271-2022.

[0065] Coal gas / natural gas: The excess air coefficient is taken as 1.1, based on the fact that gaseous fuels, such as blast furnace gas and natural gas, have good mixing uniformity with air and high combustion completeness. Only a low excess air is needed to meet the combustion requirements, which meets the requirement of "room combustion furnace, i.e., gaseous fuel air excess coefficient ≤ 1.2" in GB / T 13271-2022.

[0066] 3) Calibration factor generation step: Compare the actual reference flue gas volume calculated in step 2) with the fixed reference flue gas volume preset in the accounting system to generate a dynamic calibration factor; the dynamic calibration factor is the ratio of the actual reference flue gas volume to the fixed reference flue gas volume.

[0067] 4) Performance value adjustment step: Using the dynamic calibration factor generated in step 3), the fixed performance value in the accounting system is corrected to obtain the calibrated performance value; the correction is achieved by multiplying the fixed performance value by the dynamic calibration factor.

[0068] 5) Permit Calculation Steps: Based on the calibration performance value obtained in step 4), and combined with the fuel consumption of industrial furnaces and kilns, recalculate the permitted pollutant emissions; the fuel consumption is the actual maximum value or design consumption of the previous three years.

[0069] Through the above steps, dynamic calibration of the discharge permit amount can be achieved as fuel composition fluctuates, thereby improving the accuracy of accounting and the fairness of supervision.

[0070] It should be further explained that, during the operation of industrial furnaces, this method involves deploying an online fuel composition analysis device to collect real-time data on the actual elemental composition of the fuel, including the content of carbon, hydrogen, oxygen, sulfur, and nitrogen, as well as the ash and moisture content on the received basis. This real-time data is then input into the system's existing theoretical calculation formula for the baseline flue gas volume. While maintaining a constant excess air coefficient, the actual baseline flue gas volume reflecting the current fuel characteristics is dynamically calculated. A dynamic calibration factor is generated by comparing the actual baseline flue gas volume with a preset fixed baseline flue gas volume. This factor is then used to linearly correct the pollutant emission performance value determined based on fixed parameters in the system, obtaining a calibration performance value that varies with fuel composition.

[0071] Finally, the calibration performance value is combined with fuel consumption to recalculate the permissible emissions that accurately reflect the actual emission level. This method, by establishing a technical path of "real-time monitoring of fuel composition - dynamic calculation of baseline flue gas volume - online correction of performance value," realizes the transformation of emission permit calculation from a static parameter system to a dynamic calibration system. It organically embeds online component analysis technology into the existing calculation framework, and through the construction of dynamic calibration factors, it solves the inherent defect of fixed parameter systems that cannot adapt to fuel composition fluctuations, ensuring the consistency between the calculation results and actual emission characteristics.

[0072] The fuel composition monitoring device in step 1) includes at least one of an online industrial analyzer and an online chromatograph; the online industrial analyzer is used for component monitoring of solid fuels, and the online chromatograph is used for component monitoring of gaseous fuels; the acquisition frequency of actual elemental composition data is determined according to the fuel batch replacement cycle or operating time interval to ensure that the data represents the current fuel state.

[0073] It should be further explained that, in the data acquisition stage, this method specifically employs an online industrial analyzer to monitor the composition of solid fuels. This analyzer uses near-infrared spectroscopy or X-ray fluorescence technology to detect the elemental composition of the fuel in real time. For gaseous fuels, an online chromatograph is used, which accurately analyzes the gas components through chromatographic separation and thermal conductivity detection technology. The setting of the monitoring frequency is directly related to actual industrial production. The sampling interval is determined according to the fuel batch replacement cycle. If it is a continuous feeding system, data is collected at fixed time intervals to ensure that there is corresponding composition data for each fuel batch or each operating period. This ensures that the collected elemental composition data can truly reflect the characteristics of the fuel currently entering the furnace, providing an accurate data foundation for subsequent dynamic calculations.

[0074] Step 2) involves dynamically calculating the actual baseline flue gas volume, specifically including:

[0075] Identify the current fuel type, including solid fuel, liquid fuel, coal gas, or natural gas;

[0076] Based on the fuel type, the corresponding theoretical flue gas volume calculation formula and excess air coefficient are used; the excess air coefficient is a fixed value.

[0077] Input the actual elemental composition data into the formula to calculate the actual baseline flue gas volume.

[0078] It should be further explained that in the process of dynamically calculating the actual baseline flue gas volume, the system first automatically identifies the type of fuel currently in use, including solid fuel, liquid fuel, coal gas, or natural gas, by using the identification information of the fuel delivery pipeline or the results of fuel characteristic analysis. Based on the identified fuel type, the system calls the pre-stored corresponding theoretical flue gas volume calculation formula and the corresponding fixed excess air coefficient. Among them, solid fuel adopts the flue gas volume calculation formula based on elemental analysis and is equipped with an excess air coefficient of 1.5, liquid fuel adopts its specific calculation formula and is equipped with an excess air coefficient of 1.2, and coal gas and natural gas adopt their corresponding gaseous fuel calculation formulas and are equipped with an excess air coefficient of 1.1.

[0079] The system collects real-time data on actual elemental composition, including the content of elements such as carbon, hydrogen, oxygen, and sulfur, as well as ash and moisture content, and inputs it into the corresponding theoretical calculation formula. Through the built-in calculation module, it outputs the actual baseline flue gas volume value under the current fuel condition in real time. This dynamic calculation process ensures that the baseline flue gas volume is always synchronized with the actual fuel composition, breaking through the technical limitations of the fixed calorific value assumption.

[0080] Step 3) of generating the dynamic calibration factor further includes:

[0081] The preset fixed reference flue gas volume is determined through theoretical calculations based on the fuel's design calorific value or average calorific value.

[0082] The calculation of the dynamic calibration factor is performed automatically each time the fuel composition data is updated;

[0083] When the dynamic calibration factor exceeds the preset range, an alarm is triggered to prompt manual review or system adjustment.

[0084] It should be further explained that, in the process of generating dynamic calibration factors, the system uses a fixed reference flue gas volume pre-calculated based on the design calorific value or average calorific value as a comparison benchmark. The system automatically generates dynamic calibration factors by calculating the ratio of the actual reference flue gas volume to the fixed reference flue gas volume in real time. The system sets a reasonable range threshold for calibration factors. When the calculated dynamic calibration factor exceeds the preset reasonable range, an alarm prompt mechanism is automatically triggered to notify the operator to perform manual review or start the system's automatic adjustment program.

[0085] The calculation of this dynamic calibration factor is synchronized with the update of fuel composition data, ensuring that every change in fuel characteristics is reflected in the calibration factor in a timely manner. This establishes a dynamic calibration mechanism with self-verification and anomaly warning functions, effectively avoiding calibration errors caused by abnormal composition monitoring data or calculation deviations.

[0086] Step 4) involves adjusting performance values, specifically including:

[0087] Fixed performance values ​​are obtained from the performance value table in the accounting system, which is preset based on fuel calorific value and pollutant type.

[0088] The calibration performance value is calculated by multiplying a fixed performance value by a dynamic calibration factor;

[0089] The calibration performance values ​​are applied to pollutant types, including particulate matter, sulfur dioxide, and nitrogen oxides.

[0090] It should be further explained that, in the performance value adjustment stage, the system retrieves fixed performance values ​​based on the fuel design calorific value and pollutant type from the pre-stored performance value table. The performance value table contains baseline emission performance data for particulate matter, sulfur dioxide, and nitrogen oxides within different calorific value ranges. The system multiplies the dynamic calibration factor with the retrieved fixed performance value to generate a calibration performance value applicable to the current actual fuel composition. This adjustment process is simultaneously applied to the performance value calculation for pollutant types. Through a unified calibration mechanism, it ensures that the emission performance values ​​of particulate matter, sulfur dioxide, and nitrogen oxides can respond in real time to changes in fuel composition. This establishes a technical path for the transformation from a single fixed value to a multi-pollutant dynamic calibration system, achieving a breakthrough in the collaborative and accurate accounting of multiple pollutants for fuels with complex compositions.

[0091] Step 5) of the permit quantity calculation further includes:

[0092] Fuel consumption is determined based on the maximum actual fuel consumption over the previous three years. If the actual fuel consumption is less than one year or exceeds the design consumption, the design consumption shall be used.

[0093] Permitted emissions are calculated by multiplying fuel consumption by the calibration performance value and then multiplying by a unit conversion factor.

[0094] The accounting results are used for environmental regulatory reports, pollution discharge permit renewals, or enterprise emission management.

[0095] It should be further explained that the unit conversion factor is determined based on the unit combination of fuel consumption and calibration performance value, as follows:

[0096] Correspondence between unit combinations and conversion coefficients: fuel consumption unit Calibrate performance value units Unit conversion factor Permitted emission units tons (t) kilograms per ton (kg / t) 0.001 tons (t) <![CDATA[cubic meter (Nm 3 )]]> <![CDATA[grams per cubic meter (g / Nm 3 )]]> 0.000001 tons (t) kilogram (kg) mg / kg 0.000001 tons (t)

[0097] Calculation Example: If the heating furnace uses solid fuel, the fuel consumption determined in step 5) is the actual maximum value of 1000t / year for the previous three years, and the particulate matter calibration performance value obtained in step 4) is 5kg / t. Therefore, the permissible emission amount = 1000t / year × 5kg / t × 0.001 = 5t / year. If the drying furnace uses natural gas, the fuel consumption is the design consumption of 500,000 Nm³. 3 / year, sulfur dioxide calibration performance value is 200g / Nm 3The permitted emission level is 500,000 Nm³. 3 / year×200g / Nm 3 ×0.000001=100t / year.

[0098] It should be further explained that in the fuel consumption calculation process, the maximum actual fuel consumption of the previous three years is used as the benchmark. When the actual operating time is less than one year or the historical maximum exceeds the design consumption, the system will automatically switch to the design consumption as the calculation basis. The system will multiply the dynamically calibrated performance value with the determined fuel consumption and unify the dimensions to the annual permitted emission unit by multiplying by the unit conversion factor.

[0099] The calculated emission allowance results are directly output to the environmental regulatory reporting system for real-time updates of emission permits and dynamic adjustments to enterprise emission management. This realizes a technological shift from fixed parameter calculation to dynamic emission allowance management based on actual operating data, and builds a precise environmental regulatory system that can adapt to changes in fuel characteristics.

[0100] The method also includes a data validation step, performed after step 1) and before step 2); the data validation step includes:

[0101] The actual elemental composition data collected is checked for reasonableness, and outliers are removed;

[0102] The accuracy of online monitoring data was verified through laboratory sampling analysis.

[0103] When the data deviation exceeds the threshold, the monitoring device is automatically calibrated or switched to a backup data source.

[0104] It should be further explained that the criteria for checking the reasonableness of actual elemental composition data include the following:

[0105] Based on GB / T 212-2008 "Industrial Analysis Methods for Coal", GB / T 11062-2021 "Calculation Methods for Calorific Value, Density, Relative Density and Wobbe Index of Natural Gas", and the common fuel composition ranges in the industry, reasonable ranges for the content of each element are set:

[0106] Solid fuel (coal): C (40%–85%), H (2%–6%), O (1%–25%), S (0.2%–3%), N (0.5%–2%), ash content as received (5%–40%), moisture content as received (2%–20%);

[0107] Liquid fuel (heavy oil): C (82%–88%), H (10%–14%), O (0.5%–3%), S (0.5%–5%), N (0.1%–1%), ash content as received (0.01%–0.5%), moisture content as received (0.1%–2%).

[0108] Blast furnace gas: CO (20%~30%), H2 (1%~5%), CH4 (0.1%~1%), CO2 (15%~25%), N2 (45%~55%), O2 (≤1%);

[0109] Natural gas: CH4 (≥90%), C2H6 (1%~5%), C3H8 (0.1%~2%), CO2 (≤1%), N2 (≤5%), O2 (≤0.5%);

[0110] At the same time, the stoichiometric relationship must be met: “C+H+O+S+N+ash content received + moisture content received ≈ 100%” (solid / liquid fuel) or “sum of volume fractions of each gaseous component ≈ 100%” (gaseous fuel). Deviations exceeding ±2% are considered outliers and will be directly rejected.

[0111] The data deviation threshold and processing logic are as follows:

[0112] The deviation threshold between online monitoring data and laboratory sampling analysis data is set at ±5% (relative deviation), and the calculation formula is as follows:

[0113] ;

[0114] When the relative deviation is ≤5%, the online monitoring data is deemed valid, and the process proceeds to step 2) dynamic calculation; when the relative deviation is >5%, the monitoring device calibration procedure is automatically triggered (such as baseline calibration of online industrial analyzers or standard gas calibration of online chromatographs), and data is re-acquired after calibration; if the deviation is still >5% after 3 consecutive calibrations, the system automatically switches to a backup data source (such as a backup monitoring device or the average analysis value of the last 3 laboratory tests) and generates an alarm message (SMS + platform pop-up) to notify the maintenance personnel.

[0115] It should be further explained that after the data acquisition step, the system executes a data verification procedure. First, it automatically verifies the collected fuel element composition data, performs boundary checks by setting reasonable numerical ranges for the content of each element, and performs logical consistency verification based on the stoichiometric relationship between fuel element compositions, automatically identifying and removing abnormal data points.

[0116] Simultaneously, a laboratory sampling analysis and comparison mechanism is established to regularly cross-validate online monitoring data with data obtained from standard laboratory analysis methods. When the deviation between monitoring data and laboratory data exceeds a predetermined threshold, the system automatically initiates the calibration procedure of the monitoring device or switches to a backup data acquisition channel. This multi-verification and automatic fault-tolerance mechanism ensures the accuracy and reliability of component monitoring data, providing a solid data quality guarantee for subsequent dynamic calculations.

[0117] The method is integrated into a digital regulatory platform to achieve automated execution; the platform includes:

[0118] The data acquisition module is used to connect to the fuel composition monitoring device and acquire real-time data;

[0119] The calculation module is used to perform dynamic calculations and generate calibration factors;

[0120] The output module is used to generate calibrated emission permit reports and transmit them to the regulatory system.

[0121] It should be further explained that this method achieves full-process automation by building a dedicated digital monitoring platform. This platform includes three core functional modules: the data acquisition module establishes a real-time data connection with the fuel composition monitoring device through a standard industrial communication protocol, automatically acquires and stores elemental composition data; the calculation module has a built-in dynamic calibration algorithm engine, which can automatically call the corresponding theoretical calculation formulas to complete a series of calculations from the calculation of actual baseline flue gas volume to the generation of dynamic calibration factors.

[0122] The output module generates a discharge permit report based on the standardized format required by environmental regulations, and automatically transmits the final calibration results to the business system of the environmental regulatory department through a data interface. These three modules are seamlessly connected through a unified data bus, forming a complete automated processing link from data collection to regulatory reporting.

[0123] The method is applicable to a variety of industrial furnaces, including heating furnaces, heat treatment furnaces, and drying furnaces; fuel types cover solid fuels, liquid fuels, coal gas, and natural gas; pollutants include particulate matter, sulfur dioxide, and nitrogen oxides.

[0124] It should be further explained that this method, by establishing a unified dynamic calibration framework, enables its wide application in various types of industrial furnaces and kilns, specifically covering typical industrial thermal equipment such as heating furnaces, heat treatment furnaces, and drying furnaces and kilns, and is compatible with various fuel types such as solid fuels, liquid fuels, coal gas, and natural gas. For different furnaces and kilns with varying combustion characteristics and emission features, the system ensures the applicability of the dynamic calibration method in different application scenarios by configuring corresponding theoretical calculation formulas and parameter settings. Simultaneously, this calibration method comprehensively covers the adjustment of emission performance values ​​for major air pollutants such as particulate matter, sulfur dioxide, and nitrogen oxides, establishing a universal calibration system that can adapt to different types of industrial furnaces and kilns, multiple fuel combinations, and multi-pollutant collaborative accounting.

[0125] The method achieves continuous optimization through closed-loop control; specifically, it includes:

[0126] Regularly compare the calibrated permitted emissions with actual emission monitoring data to evaluate the calibration effectiveness;

[0127] Based on the assessment results, adjust the parameters of the fuel composition monitoring device or update the theoretical calculation formula;

[0128] Establish a historical database for trend analysis and predictive model training to further improve calibration accuracy.

[0129] It should be further explained that this method achieves continuous optimization by constructing a complete closed-loop control system. The system periodically collects monitoring concentration and flue gas flow data from the actual emission outlet, calculates the actual emission amount, and automatically compares and analyzes it with the permitted emission amount calculated based on the dynamic calibration method. The calibration effect is quantitatively evaluated by establishing a deviation evaluation model. Based on the evaluation results, the system automatically adjusts the operating parameters of the fuel composition monitoring device or optimizes and updates specific coefficients in the theoretical calculation formula.

[0130] Meanwhile, the system stores historical fuel composition data, dynamic calibration factors, actual emissions, and assessment results in a dedicated historical database. It uses this data to build trend analysis models and train prediction algorithms to achieve deep learning of fuel composition change patterns and accurate prediction of emission trends. This forms an intelligent calibration system with self-optimization capabilities, continuously improving the accuracy and adaptability of emission permit calibration.

[0131] By establishing a closed-loop feedback mechanism for real-time monitoring of fuel composition and dynamic calibration factors, the traditional static accounting system is transformed into a dynamic calibration system capable of responding to changes in fuel characteristics. This method dynamically corrects the baseline flue gas volume and performance values ​​based on actual elemental composition data, solving the problem of inaccurate calculations in fixed-parameter systems when fuel composition fluctuates, and effectively improving the accuracy and reliability of emission permit calculations.

[0132] This method constructs a fully automated system from data acquisition and dynamic calculation to result output, achieving unified calibration for multiple fuel types and pollutant categories. Through closed-loop control and continuous optimization mechanisms, the system can adapt to changes in fuel characteristics and continuously optimize calibration accuracy, enhancing the targeting and fairness of environmental supervision and providing technical support for precise management by enterprises and scientific decision-making by regulatory authorities.

[0133] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0134] 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. A method for calibrating emission permits under fuel composition fluctuations, applied to an industrial furnace pollutant emission permit calculation system, wherein the system determines a baseline flue gas volume based on fuel type and calorific value through theoretical calculation, derives a fixed performance value in conjunction with pollutant emission concentration standards, and determines the permitted emission amount based on fuel consumption; the method is characterized by comprising the following steps: 1) Data acquisition steps: During the operation of industrial furnaces and kilns, the actual elemental composition data of the fuel currently used is collected in real time or periodically through the deployed fuel composition monitoring device; the actual elemental composition data includes at least the carbon content, hydrogen content, oxygen content, sulfur content, nitrogen content, as-received ash content, and as-received moisture content; 2) Dynamic calculation step: Based on the actual elemental composition data obtained in step 1), combined with the theoretical flue gas volume calculation formula corresponding to the fuel type and the preset excess air coefficient, the actual benchmark flue gas volume corresponding to the current fuel is dynamically calculated; The theoretical flue gas volume calculation formula is the original formula used in the accounting system to determine the baseline flue gas volume, and the preset excess air coefficient is selected as a fixed value according to the fuel type. 3) Calibration factor generation step: Compare the actual reference flue gas volume calculated in step 2) with the fixed reference flue gas volume preset in the accounting system to generate a dynamic calibration factor; The dynamic calibration factor is the ratio of the actual reference flue gas volume to the fixed reference flue gas volume; 4) Performance value adjustment step: Using the dynamic calibration factor generated in step 3), the fixed performance value in the accounting system is corrected to obtain the calibrated performance value; the correction is achieved by multiplying the fixed performance value by the dynamic calibration factor; 5) Permit Calculation Step: Based on the calibration performance value obtained in step 4), and combined with the fuel consumption of industrial furnaces and kilns, recalculate the permitted pollutant emissions; the fuel consumption is the actual maximum value or design consumption of the previous three years.

2. The method for calibrating emission permit quantities under fuel composition fluctuations according to claim 1, characterized in that: The fuel composition monitoring device mentioned in step 1) includes at least one of an online industrial analyzer and an online chromatograph; the online industrial analyzer is used for component monitoring of solid fuels, and the online chromatograph is used for component monitoring of gaseous fuels; the acquisition frequency of the actual elemental composition data is determined according to the fuel batch replacement cycle or operating time interval to ensure that the data represents the current fuel state.

3. The method for calibrating emission permit quantities under fuel composition fluctuations according to claim 1, characterized in that: The process of dynamically calculating the actual baseline flue gas volume as described in step 2) specifically includes: Identify the current fuel type, including solid fuel, liquid fuel, coal gas, or natural gas; Based on the fuel type, the corresponding theoretical flue gas volume calculation formula and excess air coefficient are invoked; the excess air coefficient is a fixed value. Input the actual elemental composition data into the formula to calculate the actual baseline flue gas volume.

4. The method for calibrating emission permit quantities under fuel composition fluctuations according to claim 1, characterized in that: The generation of the dynamic calibration factor in step 3) further includes: The preset fixed reference flue gas volume is determined through theoretical calculations based on the fuel's design calorific value or average calorific value. The calculation of the dynamic calibration factor is performed automatically each time the fuel composition data is updated; When the dynamic calibration factor exceeds the preset range, an alarm is triggered to prompt manual review or system adjustment.

5. The method for calibrating emission permit quantities under fuel composition fluctuations according to claim 1, characterized in that: The performance value adjustment mentioned in step 4) specifically includes: The fixed performance value is obtained by querying the performance value table of the accounting system, which is preset based on fuel calorific value and pollutant type. The calibration performance value is calculated by multiplying a fixed performance value by a dynamic calibration factor; The calibration performance values ​​are applied to pollutant types, including particulate matter, sulfur dioxide, and nitrogen oxides.

6. The method for calibrating emission permit quantities under fuel composition fluctuations according to claim 1, characterized in that: The license quantity calculation described in step 5) further includes: Fuel consumption is determined based on the maximum actual fuel consumption over the previous three years. If the actual fuel consumption is less than one year or exceeds the design consumption, the design consumption shall be used. Permitted emissions are calculated by multiplying fuel consumption by the calibration performance value and then multiplying by a unit conversion factor. The accounting results are used for environmental regulatory reports, pollution discharge permit renewals, or enterprise emission management.

7. The method for calibrating emission permit quantities under fuel composition fluctuations according to claim 1, characterized in that: The method also includes a data validation step, performed after step 1) and before step 2); The data verification steps include: The actual elemental composition data collected is checked for reasonableness, and outliers are removed; The accuracy of online monitoring data was verified through laboratory sampling analysis. When the data deviation exceeds the threshold, the monitoring device is automatically calibrated or switched to a backup data source.

8. The method for calibrating emission permit quantities under fuel composition fluctuations according to claim 1, characterized in that: The method is integrated into a digital supervision platform to achieve automated execution; the platform includes: The data acquisition module is used to connect to the fuel composition monitoring device and acquire real-time data; The calculation module is used to perform dynamic calculations and generate calibration factors; The output module is used to generate calibrated emission permit reports and transmit them to the regulatory system.

9. The method for calibrating emission permit quantities under fuel composition fluctuations according to claim 1, characterized in that: The method is applicable to a variety of industrial furnaces, including heating furnaces, heat treatment furnaces, and drying furnaces; the fuel types cover solid fuels, liquid fuels, coal gas, and natural gas; the pollutants include particulate matter, sulfur dioxide, and nitrogen oxides.

10. The method for calibrating emission permit quantities under fuel composition fluctuations according to claim 1, characterized in that: The method achieves continuous optimization through closed-loop control; specifically, it includes: Regularly compare the calibrated permitted emissions with actual emission monitoring data to evaluate the calibration effectiveness; Based on the assessment results, adjust the parameters of the fuel composition monitoring device or update the theoretical calculation formula; Establish a historical database for trend analysis and predictive model training.

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