A method and system for performance evaluation and optimization of oxygen carriers for carbon capture

Abstract

The present application relates to the technical field of carbon capture, in particular to a method and system for evaluating and optimizing the performance of oxygen carriers for carbon capture, which comprises S1, carrying out Redox cycle based on a fixed bed reactor, analyzing the concentration values of NOx and CO2 in flue gas, and obtaining emission index values; S2, calculating the gas yield of CO2 in flue gas and the combustion efficiency of fuel, and obtaining conversion and combustion index values according to the gas yield of CO2 in flue gas and the combustion efficiency of fuel; S3, obtaining the energy spectrum of oxygen carriers before and after reaction and carrying out X-ray diffraction analysis, and obtaining life index values according to the specific surface area of oxygen carriers before and after reaction and the spectrum of the same element; S4, calculating the performance index values of oxygen carriers according to the obtained emission index values, conversion and combustion index values and life index values, and optimizing the performance of oxygen carriers according to the performance index values of oxygen carriers. By using the method, the carbon capture performance of oxygen carriers can be accurately evaluated and optimized.

Description

Technical Field

[0001] This invention relates to the field of carbon capture technology, and more specifically to a method, system, electronic device, and machine-readable storage medium for evaluating and optimizing the performance of oxygen carriers used in carbon capture. Background Technology

[0002] Currently, the petrochemical industry accounts for approximately 80% of total CO2 emissions, and combustion-generated CO2 within the petrochemical sector accounts for 63% of these emissions. Therefore, the need for carbon capture in combustion (CCC) technologies to enrich CO2 produced in petrochemical production is urgent. Chemical looping combustion, using oxygen carriers as a medium, is a commonly used CCC method; however, this technology is primarily applied to carbon capture in coal-fired power plants, solid waste, or natural gas combustion. Furthermore, given that petrochemical applications often involve mixed high-calorific-value gases dominated by light hydrocarbons, there is a lack of methods for quantitatively evaluating the performance of corresponding oxygen carriers, limiting the application of CCC in petrochemical settings.

[0003] Therefore, there is an urgent need for a method and system for evaluating and optimizing the performance of oxygen carriers for carbon capture in order to solve the above problems. Summary of the Invention

[0004] The purpose of this invention is to address the problem in the prior art, particularly in the petrochemical industry, that the performance of oxygen carriers cannot be quantitatively evaluated, and to provide a method, system, electronic device, and machine-readable storage medium for evaluating and optimizing the performance of oxygen carriers for carbon capture.

[0005] To achieve the above objectives, the first aspect of the present invention provides a method for performance evaluation and optimization of oxygen carriers for carbon capture, the method comprising the following steps:

[0006] S1. Based on a fixed-bed reactor, multiple Redox (oxidation-reduction) cycles were carried out to analyze the average concentrations of NOx and CO2 in the flue gas and obtain the emission index values.

[0007] S2. Calculate the CO2 gas yield in the flue gas and the combustion efficiency of the fuel, and obtain the conversion and combustion index values ​​based on the CO2 gas yield in the flue gas and the combustion efficiency of the fuel.

[0008] S3. Obtain the energy spectrum of the oxygen support before and after the reaction and conduct X-ray diffraction analysis. Based on the specific surface area of ​​the oxygen support before and after the reaction and the spectrum of the same element, obtain the lifetime index value.

[0009] S4. Based on the obtained emission index values, conversion and combustion index values, and lifespan index values, calculate the performance index values ​​of the oxygen carrier, and optimize the performance of the oxygen carrier based on the performance index values ​​of the oxygen carrier.

[0010] Preferably, in step S1, the analysis of the average concentrations of NOx and CO2 in the flue gas to obtain the emission index value Iexhaust specifically includes:

[0011] When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the CO2 concentration percentage is greater than or equal to 95%, the Iexhaust value is 4;

[0012] When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the percentage of CO2 concentration is greater than or equal to 90% and less than or equal to 95%, Iexhaust is 3;

[0013] When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the CO2 concentration percentage is less than 90%, Iexhaust is 2;

[0014] When the NOx concentration in the flue gas is greater than 30 mg / m³ 3 When the CO2 concentration percentage is less than 90%, Iexhaust is 1.

[0015] Preferably, in step S2, the formula for calculating the CO2 gas yield in the flue gas is:

[0016]

[0017] Where Yco2 is the CO2 gas yield; Cco2,out is the volume fraction of CO2 in the flue gas measured at a certain time; Vout is the flue gas volume measured at a certain time; and Cco,out is the volume fraction of CO in the flue gas measured at a certain time. The volume fraction of CH4 in the flue gas measured at a certain moment; The volume fraction of C2H6 in the flue gas measured at a certain moment; The volume fraction of C3H8 in the flue gas measured at a certain moment.

[0018] Preferably, in step S2, the formula for calculating the fuel combustion efficiency is:

[0019]

[0020] Where, η c For fuel combustion efficiency; F out,red yco is the exhaust gas flow rate during the reduction stage; Hco is the lower heating value of CO; Mco is the molar mass of CO; yco is the volume fraction of CO in the flue gas; H CH4 The lower heating value of CH4; M CH4 y is the molar mass of CH4; CH4 H represents the volume fraction of CH4 in the flue gas.H2 The lower heating value of H2; M H2 y is the molar mass of H2; H2 The volume fraction of H2 in the flue gas; Hc is the lower heating value of the gas in the oxidation stage; Mc is the molar mass of the gas in the oxidation stage; Nc,ox is the mass of the gas in the oxidation stage; m fuel For fuel mass; H fuel It represents the lower heating value of the fuel.

[0021] Preferably, in step S2, obtaining the conversion and combustion index value Icombustion based on the CO2 gas yield in the flue gas and the fuel combustion efficiency specifically includes:

[0022] When the CO2 gas yield in the flue gas is greater than or equal to 90% and the fuel combustion efficiency is greater than or equal to 97%, Icombustion is 4.

[0023] When the CO2 gas yield in the flue gas is greater than or equal to 88% and the fuel combustion efficiency is greater than or equal to 93%, Icombustion is 3;

[0024] When the CO2 gas yield in the flue gas is greater than or equal to 80% and the fuel combustion efficiency is greater than or equal to 90%, Icombustion is 2.

[0025] When the CO2 gas yield in the flue gas and the fuel combustion efficiency are not as described above, Icombustion is 1.

[0026] Preferably, in step S3, the lifetime index value I is obtained based on the specific surface area of ​​the oxygen carrier before and after the reaction and the spectrum of the same element. life Specifically, it includes:

[0027] When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 80%, and the change in the spectral value of the same element is no greater than 60%, I life It is 4;

[0028] When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 60%, and the change in the spectral value of the same element is no greater than 60%, I life It is 3;

[0029] When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 80%, and the change in the spectral value of the same element is no greater than 50%, I life It is 2;

[0030] When the changes in the specific surface area of ​​the oxygen support and the spectral values ​​of the same elements before and after the reaction are not as described above, I life The value is 1.

[0031] Preferably, in step S4, the formula for calculating the performance index value of the oxygen carrier is:

[0032] I=0.2Iexhaust+0.5Icombustion+0.3I life

[0033] Where I represents the performance index value of the oxygen carrier, Iexhaust represents the emission index value, Icombustion represents the conversion and combustion index value, and I... life This refers to lifespan index values.

[0034] Preferably, in step S4, optimizing the performance of the oxygen carrier based on its performance index values ​​specifically includes:

[0035] When the performance index value of the oxygen carrier is less than the set performance value, if the conversion and combustion index value is less than the set conversion and combustion value and / or the life index value is less than the set life value, then the oxygen carrier substrate should be optimized during the preparation of the oxygen carrier.

[0036] Preferably, it further includes: when the performance index value of the oxygen carrier is not less than the set performance value, there is no need to optimize the performance of the oxygen carrier.

[0037] Preferably, the Redox cycle is 80-120 times.

[0038] Preferably, the oxygen carrier is a metal-based oxygen carrier.

[0039] A second aspect of the present invention provides a performance evaluation and optimization system for an oxygen carrier used in carbon capture, applied to the performance evaluation and optimization method described above. The performance evaluation and optimization system includes:

[0040] The emission index value acquisition module is used to perform multiple Redox cycles based on a fixed-bed reactor, analyze the average concentrations of NOx and CO2 in the flue gas, and obtain emission index values.

[0041] The conversion and combustion index value acquisition module is used to calculate the CO2 gas yield and fuel combustion efficiency in flue gas, and obtain the conversion and combustion index values ​​based on the CO2 gas yield and fuel combustion efficiency in flue gas.

[0042] The lifetime index value acquisition module is used to acquire the energy spectrum of the oxygen carrier before and after the reaction and to carry out X-ray diffraction analysis. Based on the specific surface area of ​​the oxygen carrier before and after the reaction and the spectrum of the same element, the lifetime index value is obtained.

[0043] The performance index value acquisition and optimization module is used to calculate the performance index value of the oxygen carrier based on the obtained emission index value, conversion and combustion index value and lifespan index value, and to optimize the performance of the oxygen carrier based on the performance index value.

[0044] A third aspect of the present invention provides an electronic device, including at least one processor, at least one memory, and a communication interface; the processor, the memory, and the communication interface communicate with each other; the memory stores program instructions executable by the processor, and the processor calls the program instructions to execute the performance evaluation and optimization method described above.

[0045] A fourth aspect of the present invention provides a machine-readable storage medium having instructions stored thereon, the instructions being configured to enable the machine-readable storage medium to execute the performance evaluation and optimization method described above.

[0046] According to the above technical solution, the method and system for evaluating and optimizing the performance of oxygen carriers for carbon capture can obtain the emission index values, conversion and combustion index values, and lifespan index values ​​of the oxygen carrier in actual application. Furthermore, the performance index values ​​of the oxygen carrier can be obtained based on these emission index values, conversion and combustion index values, and lifespan index values. This not only enables accurate evaluation of the performance of the oxygen carrier, but also allows the evaluation results to be used to guide the preparation of the oxygen carrier. Attached Figure Description

[0047] Figure 1 This is a flowchart of a method for evaluating and optimizing the performance of oxygen carriers used in carbon capture;

[0048] Figure 2 This is the X-ray diffraction analysis diagram of the Fe-based oxygen support in Example 1 before the reaction;

[0049] Figure 3 This is an X-ray diffraction analysis diagram of the Fe-based oxygen support in Example 1 after the reaction. Detailed Implementation

[0050] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the present invention.

[0051] The first aspect of this invention provides a method for evaluating and optimizing the performance of oxygen carriers used for carbon capture, such as... Figure 1 As shown, the method for evaluating and optimizing the performance of oxygen carriers for carbon capture includes the following steps:

[0052] S1. Based on a fixed-bed reactor, multiple Redox cycles were carried out to analyze the average concentrations of NOx and CO2 in the flue gas and obtain the emission index values.

[0053] S2. Calculate the CO2 gas yield in the flue gas and the combustion efficiency of the fuel, and obtain the conversion and combustion index values ​​based on the CO2 gas yield in the flue gas and the combustion efficiency of the fuel.

[0054] S3. Obtain the energy spectrum of the oxygen support before and after the reaction and conduct X-ray diffraction analysis. Based on the specific surface area of ​​the oxygen support before and after the reaction and the spectrum of the same element, obtain the lifetime index value.

[0055] S4. Based on the obtained emission index values, conversion and combustion index values, and lifespan index values, calculate the performance index values ​​of the oxygen carrier, and optimize the performance of the oxygen carrier based on the performance index values ​​of the oxygen carrier.

[0056] According to the above technical solution, the method for evaluating and optimizing the performance of oxygen carriers for carbon capture obtains the emission index values, conversion and combustion index values, and lifetime index values ​​of the oxygen carrier in actual application. Furthermore, the performance index values ​​of the oxygen carrier are obtained based on these emission index values, conversion and combustion index values, and lifetime index values. This not only enables accurate evaluation of the performance of the oxygen carrier, but also allows the evaluation results to be used to guide the preparation of the oxygen carrier.

[0057] In the carbon capture oxygen carrier performance evaluation and optimization method of the present invention, preferably, in step S1, the Redox cycle is 80-120 times, more preferably 90-110 times, and most preferably 100 times, thereby improving the accuracy of the average value of NOx and CO2 concentrations in the obtained flue gas, and thus improving the accuracy of the oxygen carrier performance evaluation.

[0058] In the carbon capture oxygen carrier performance evaluation and optimization method of the present invention, preferably, in step S2, the formula for calculating the CO2 gas yield in the flue gas is:

[0059]

[0060] Where Yco2 is the CO2 gas yield; Cco2,out is the volume fraction of CO2 in the flue gas measured at a certain time; Vout is the flue gas volume measured at a certain time; and Cco,out is the volume fraction of CO in the flue gas measured at a certain time. The volume fraction of CH4 in the flue gas measured at a certain moment; The volume fraction of C2H6 in the flue gas measured at a certain moment; This refers to the volume fraction of C3H8 in the flue gas measured at a certain moment; specifically, it refers to obtaining the above parameter values ​​and calculating the CO2 gas yield at the same moment, such as time t1.

[0061] In another preferred embodiment, the formula for calculating the combustion efficiency of the fuel is:

[0062]

[0063] Where, η c For fuel combustion efficiency; F out,redyco is the exhaust gas flow rate during the reduction stage; Hco is the lower heating value of CO; Mco is the molar mass of CO; yco is the volume fraction of CO in the flue gas; H CH4 The lower heating value of CH4; M CH4 y is the molar mass of CH4; CH4 H represents the volume fraction of CH4 in the flue gas. H2 The lower heating value of H2; M H2 y is the molar mass of H2; H2 The volume fraction of H2 in the flue gas; Hc is the lower heating value of the gas in the oxidation stage; Mc is the molar mass of the gas in the oxidation stage; Nc,ox is the mass of the gas in the oxidation stage; m fuel For fuel mass; H fuel It represents the lower heating value of the fuel.

[0064] In this invention, the calculation formulas for CO2 gas yield in flue gas (Yco2) and fuel combustion efficiency (η) are provided. c In practical applications, it can effectively improve the accuracy of the obtained conversion and combustion index values.

[0065] To further provide a scheme that can accurately quantify the performance of oxygen carriers for carbon capture, specifically, in step S1, the analysis of the average concentrations of NOx and CO2 in the flue gas and the obtaining of the emission index value Iexhaust specifically includes:

[0066] When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the CO2 concentration percentage is greater than or equal to 95%, the Iexhaust value is 4;

[0067] When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the percentage of CO2 concentration is greater than or equal to 90% and less than or equal to 95%, Iexhaust is 3;

[0068] When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the CO2 concentration percentage is less than 90%, Iexhaust is 2;

[0069] When the NOx concentration in the flue gas is greater than 30 mg / m³ 3 When the CO2 concentration percentage is less than 90%, Iexhaust is 1.

[0070] In step S2, obtaining the conversion and combustion index value Icombustion based on the CO2 gas yield in the flue gas and the fuel combustion efficiency specifically includes:

[0071] When the CO2 gas yield in the flue gas is greater than or equal to 90% and the fuel combustion efficiency is greater than or equal to 97%, Icombustion is 4.

[0072] When the CO2 gas yield in the flue gas is greater than or equal to 88% and the fuel combustion efficiency is greater than or equal to 93%, Icombustion is 3;

[0073] When the CO2 gas yield in the flue gas is greater than or equal to 80% and the fuel combustion efficiency is greater than or equal to 90%, Icombustion is 2; where CO2 gas yield refers to the ratio of CO2 in the flue gas to all carbon-containing gases.

[0074] When the CO2 gas yield in the flue gas and the fuel combustion efficiency are not as described above, Icombustion is 1.

[0075] In step S3, the lifetime index value I is obtained based on the specific surface area of ​​the oxygen carrier before and after the reaction and the spectra of the same elements. life Specifically, it includes:

[0076] When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 80%, and the change in the spectral value of the same element is no greater than 60%, I life It is 4;

[0077] When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 60%, and the change in the spectral value of the same element is no greater than 60%, I life It is 3;

[0078] When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 80%, and the change in the spectral value of the same element is no greater than 50%, I life It is 2;

[0079] When the changes in the specific surface area of ​​the oxygen support and the spectral values ​​of the same elements before and after the reaction are not as described above, I life The value is 1.

[0080] In step S4, the formula for calculating the performance index value of the oxygen carrier is:

[0081] I=0.2Iexhaust+0.5Icombustion+0.3I life

[0082] Where I represents the performance index value of the oxygen carrier, Iexhaust represents the emission index value, Icombustion represents the conversion and combustion index value, and I... lifeThis refers to the lifespan index value. Specifically, when the oxygen carrier's performance index value I is greater than or equal to 3.5 and less than or equal to 4, it indicates that the current oxygen carrier's performance is excellent, meets the needs of practical applications, and requires no performance optimization; when the oxygen carrier's performance index value I is greater than or equal to 2.4 and less than or equal to 3.5, it indicates that the current oxygen carrier's performance is medium, and there is room for further performance optimization; when the oxygen carrier's performance index value I is less than 2.4, it indicates that the current oxygen carrier's performance is poor, cannot meet the needs of practical applications, and urgently requires performance optimization.

[0083] In the carbon capture oxygen carrier performance evaluation and optimization method of the present invention, preferably, step S4, the optimization of the oxygen carrier performance based on the performance index value of the oxygen carrier, specifically includes:

[0084] When the performance index value of the oxygen carrier is less than the set performance value, if the conversion and combustion index value is less than the set conversion and combustion value and / or the life index value is less than the set life value, then the oxygen carrier substrate should be optimized during the preparation of the oxygen carrier; when the performance index value of the oxygen carrier is not less than the set value, then there is no need to optimize the performance of the oxygen carrier.

[0085] In one specific embodiment, the oxygen support can be a metal-based oxygen support, and further, the metal-based oxygen support includes Fe-based oxygen support, Cu-based oxygen support, and Fe-Cu mixed-based oxygen support, etc. In a more specific embodiment, when the oxygen carrier is an Fe-based oxygen carrier, if the performance index value of the oxygen carrier is less than the set performance value and the conversion and combustion index value is less than the set conversion and combustion value, then the oxygen carrier substrate is optimized during the preparation of the oxygen carrier. Specifically, this includes adding Cu during the preparation of the Fe-based oxygen carrier, where the mass of Cu can be 0.1-0.5 times that of Fe. When the oxygen carrier is an Fe-based oxygen carrier, if the performance index value of the oxygen carrier is less than the set performance value and the lifetime index value is less than the set lifetime value, then the oxygen carrier substrate is optimized during the preparation of the oxygen carrier. Specifically, this includes adding Cu during the preparation of the Fe-based oxygen carrier, where the mass of Cu can be 0.1-0.5 times that of Fe. When the oxygen carrier is an Fe-based oxygen carrier, if the performance index value of the oxygen carrier is less than the set performance value, and the conversion and combustion index value and lifetime index value are both less than the set lifetime value, then the oxygen carrier substrate is optimized during the preparation of the oxygen carrier. Specifically, this includes adding Cu during the preparation of the Fe-based oxygen carrier, where the mass of Cu can be 0.1-0.5 times that of Fe.

[0086] Similarly, when the oxygen carrier is a Cu-based oxygen carrier, if the performance index value of the oxygen carrier is less than the set performance value and the conversion and combustion index value is less than the set conversion and combustion value, then optimization is performed in conjunction with the substrate of the oxygen carrier during the preparation of the oxygen carrier. Specifically, this includes adding Ni during the preparation of the Cu-based oxygen carrier, where the mass of Ni can be 0.1-0.5 times that of Cu. When the oxygen carrier is a Cu-based oxygen carrier, if the performance index value of the oxygen carrier is less than the set performance value and the lifetime index value is less than the set lifetime value, then optimization is performed in conjunction with the substrate of the oxygen carrier during the preparation of the oxygen carrier. Specifically, this includes adding Ni during the preparation of the Cu-based oxygen carrier, where the mass of Ni can be 0.1-0.5 times that of Cu. When the oxygen carrier is a Cu-based oxygen carrier, if the performance index value of the oxygen carrier is less than the set performance value, and the conversion and combustion index value and lifetime index value are both less than the set lifetime value, then optimization is performed in conjunction with the substrate of the oxygen carrier during the preparation of the oxygen carrier. Specifically, this includes adding Ni during the preparation of the Cu-based oxygen carrier, where the mass of Ni can be 0.1-0.5 times that of Cu.

[0087] In another specific implementation, the set conversion and combustion value and the set lifespan value are reference values ​​for the oxygen carrier when the performance index value I is greater than or equal to 3.5 and less than or equal to 4. More specifically, the set conversion and combustion value and the set lifespan value are both 4.

[0088] A second aspect of the present invention provides a performance evaluation and optimization system for an oxygen carrier used in carbon capture, applied to the performance evaluation and optimization method described above. The performance evaluation and optimization system for an oxygen carrier used in carbon capture includes:

[0089] The emission index value acquisition module is used to perform multiple Redox cycles based on a fixed-bed reactor, analyze the average concentrations of NOx and CO2 in the flue gas, and obtain emission index values.

[0090] The conversion and combustion index value acquisition module is used to calculate the CO2 gas yield and fuel combustion efficiency in flue gas, and obtain the conversion and combustion index values ​​based on the CO2 gas yield and fuel combustion efficiency in flue gas.

[0091] The lifetime index value acquisition module is used to acquire the energy spectrum of the oxygen carrier before and after the reaction and to carry out X-ray diffraction analysis. Based on the specific surface area of ​​the oxygen carrier before and after the reaction and the spectrum of the same element, the lifetime index value is obtained.

[0092] The performance index value acquisition and optimization module is used to calculate the performance index value of the oxygen carrier based on the obtained emission index value, conversion and combustion index value and lifespan index value, and to optimize the performance of the oxygen carrier based on the performance index value.

[0093] According to the above technical solution, based on the carbon capture oxygen carrier performance evaluation and optimization system, by obtaining the emission index values, conversion and combustion index values, and lifespan index values ​​of the oxygen carrier in actual application, and further obtaining the performance index values ​​of the oxygen carrier based on these emission index values, conversion and combustion index values, and lifespan index values, it is possible not only to achieve accurate evaluation of the oxygen carrier performance, but also to use the evaluation results of the oxygen carrier performance to guide the preparation of the oxygen carrier.

[0094] A third aspect of the present invention provides an electronic device, including at least one processor, at least one memory, and a communication interface; the processor, the memory, and the communication interface communicate with each other; the memory stores program instructions executable by the processor, and the processor calls the program instructions to execute the performance evaluation and optimization method.

[0095] A fourth aspect of the present invention provides a machine-readable storage medium having instructions stored thereon, the instructions being configured to enable the machine-readable storage medium to execute the performance evaluation and optimization method described above.

[0096] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto.

[0097] Example 1

[0098] Adopting such Figure 1 The method for evaluating and optimizing the performance of oxygen carriers for carbon capture, as shown, is used to evaluate the performance of Fe-based oxygen carriers. Specifically, the method includes the following steps:

[0099] S1. Based on a fixed-bed reactor, multiple Redox cycles were carried out to analyze the average concentrations of NOx and CO2 in the flue gas and obtain the emission index values.

[0100] S2. Calculate the CO2 gas yield in the flue gas and the combustion efficiency of the fuel, and obtain the conversion and combustion index values ​​based on the CO2 gas yield in the flue gas and the combustion efficiency of the fuel.

[0101] S3. Obtain the energy spectrum of the oxygen support before and after the reaction and conduct X-ray diffraction analysis. Based on the specific surface area of ​​the oxygen support before and after the reaction and the spectrum of the same element, obtain the lifetime index value.

[0102] S4. Based on the obtained emission index values, conversion and combustion index values, and lifespan index values, calculate the performance index values ​​of the oxygen carrier, and optimize the performance of the oxygen carrier based on the performance index values ​​of the oxygen carrier.

[0103] In step S1, the average concentrations of NOx and CO2 in the flue gas are analyzed to obtain the emission index value Iexhaust, specifically including:

[0104] When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the CO2 concentration percentage is greater than or equal to 95%, the Iexhaust value is 4;

[0105] When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the percentage of CO2 concentration is greater than or equal to 90% and less than or equal to 95%, Iexhaust is 3;

[0106] When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the CO2 concentration percentage is less than 90%, Iexhaust is 2;

[0107] When the NOx concentration in the flue gas is greater than 30 mg / m³ 3 When the CO2 concentration percentage is less than 90%, Iexhaust is 1;

[0108] In step S2, the formula for calculating the CO2 gas yield in the flue gas is:

[0109]

[0110] Where Yco2 is the CO2 gas yield; Cco2,out is the volume fraction of CO2 in the flue gas measured at a certain time; Vout is the flue gas volume measured at a certain time; and Cco,out is the volume fraction of CO in the flue gas measured at a certain time. The volume fraction of CH4 in the flue gas measured at a certain moment; The volume fraction of C2H6 in the flue gas measured at a certain moment; The volume fraction of C3H8 in the flue gas measured at a certain moment;

[0111] In step S2, the formula for calculating the fuel combustion efficiency is:

[0112]

[0113] Where, η c For fuel combustion efficiency; F out,red yco is the exhaust gas flow rate during the reduction stage; Hco is the lower heating value of CO; Mco is the molar mass of CO; yco is the volume fraction of CO in the flue gas; H CH4 The lower heating value of CH4; M CH4 y is the molar mass of CH4; CH4 H represents the volume fraction of CH4 in the flue gas. H2The lower heating value of H2; M H2 y is the molar mass of H2; H2 The volume fraction of H2 in the flue gas; Hc is the lower heating value of the gas in the oxidation stage; Mc is the molar mass of the gas in the oxidation stage; Nc,ox is the mass of the gas in the oxidation stage; m fuel For fuel mass; H fuel The lower heating value of the fuel;

[0114] In step S2, obtaining the conversion and combustion index value Icombustion based on the CO2 gas yield and combustion efficiency in the flue gas specifically includes:

[0115] When the CO2 gas yield in the flue gas is greater than or equal to 90% and the fuel combustion efficiency is greater than or equal to 97%, Icombustion is 4.

[0116] When the CO2 gas yield in the flue gas is greater than or equal to 88% and the fuel combustion efficiency is greater than or equal to 93%, Icombustion is 3;

[0117] When the CO2 gas yield in the flue gas is greater than or equal to 80% and the fuel combustion efficiency is greater than or equal to 90%, Icombustion is 2.

[0118] When the CO2 gas yield in the flue gas and the fuel combustion efficiency are not as described above, Icombustion is 1;

[0119] In step S3, the lifetime index value I is obtained based on the specific surface area of ​​the oxygen carrier before and after the reaction and the spectra of the same elements. life Specifically, it includes:

[0120] When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 80%, and the change in the spectral value of the same element is no greater than 60%, I life It is 4;

[0121] When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 60%, and the change in the spectral value of the same element is no greater than 60%, I life It is 3;

[0122] When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 80%, and the change in the spectral value of the same element is no greater than 50%, I life It is 2;

[0123] When the changes in the specific surface area of ​​the oxygen support and the spectral values ​​of the same elements before and after the reaction are not as described above, I life =1;

[0124] In step S4, the formula for calculating the performance index value of the oxygen carrier is:

[0125] I=0.2Iexhaust+0.5Icombustion+0.3I life

[0126] Where I represents the performance index value of the oxygen carrier, Iexhaust represents the emission index value, Icombustion represents the conversion and combustion index value, and I... life This refers to lifespan index values;

[0127] In step S4, optimizing the performance of the oxygen carrier based on its performance index values ​​specifically includes:

[0128] When the performance index value of the oxygen carrier is less than the set performance value, if the conversion and combustion index value is less than the set conversion and combustion value and / or the life index value is less than the set life value, then the oxygen carrier substrate should be optimized during the preparation of the oxygen carrier; when the performance index value of the oxygen carrier is not less than the set value, then there is no need to optimize the performance of the oxygen carrier.

[0129] In practical applications:

[0130] (1) A Redox cycle was carried out 100 times in a fixed-bed reactor. The fluidizing gas was a N2 / CO2 mixture with a concentration ratio of 8:2 and a total gas flow rate of 10 L / min. The fuel gas mainly consisted of methane, ethane, and propane, with concentrations of 87.31%, 4.17%, and 1.78%, respectively. The reaction temperature was 850℃~1000℃, and the reaction pressure was atmospheric pressure. Taking 950℃ as an example, the CO2 emission concentration was 94%, and the NOx concentration was less than 30 mg / m³. 3 The emission index Iexhaust was found to be 3.

[0131] (2) The CO2 gas yield and fuel combustion efficiency were calculated based on the flue gas composition. The CO2 gas yield was 93.5% and the fuel combustion efficiency was 95.8%, thus the conversion and combustion index Icombustion was 3.

[0132] (3) Obtain the energy spectrum of the oxygen support before and after the reaction and perform X-ray diffraction analysis. (See reference...) Figure 2-3 It was found that the surface of the fresh oxygen carrier was covered with fine particles, resulting in a high specific surface area. Although the specific surface area decreased slightly during the initial operation, it maintained a relatively stable structure in subsequent experiments. Specifically, the main crystalline phases of natural iron ore are Fe2O3 and SiO2; the main crystalline phases of the oxygen carrier after reaction are Fe2O3, Fe3O4, and SiO2. The results indicate that the iron ore is mainly reduced to Fe3O4 in the fuel reactor, and the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no more than 80%, and the change in the spectral values ​​of the same elements before and after the reaction is no more than 60%, thus obtaining the lifetime index I.life The value is 4.

[0133] (4) Calculate the performance index value I of the oxygen carrier according to the formula.

[0134] I=0.2Iexhaust+0.5Icombustion+0.3I life =0.2*3+0.5*3+0.3*4=3.3, meaning the obtained oxygen carrier performance index value is within the range and needs further optimization;

[0135] (5) Analysis of the performance index value I of the oxygen carrier revealed that the conversion and combustion index value Icombustion was less than the set conversion and combustion value, i.e., the optimal value of 4 was not reached. Therefore, when preparing the Fe-based oxygen carrier, an appropriate amount of Cu was added. Specifically, the mass of Cu could be 0.25 times the mass of Fe.

[0136] Testing has shown that the oxygen carrier performance evaluation and optimization method for carbon capture described in this invention can not only accurately evaluate the performance of oxygen carriers in practical applications, but also use the evaluation results to guide the preparation of oxygen carriers.

[0137] Example 2

[0138] The implementation follows the same procedure as Example 1, but differs in that it is used to evaluate the performance of Cu-based oxygen supports in practical applications.

[0139] (1) A Redox cycle was carried out 100 times in a fixed-bed reactor. The fluidizing gas was a N2 / CO2 mixture with a concentration ratio of 8:2 and a total gas flow rate of 10 L / min. The fuel gas mainly consisted of methane, ethane, and propane, with concentrations of 87.31%, 4.17%, and 1.78%, respectively. The reaction temperature was 850℃ and the reaction pressure was atmospheric pressure. Taking 850℃ as an example, the CO2 emission concentration was 94.5% and the NOx concentration was less than 30 mg / m³. 3 The emission index Iexhaust was found to be 3.

[0140] (2) The CO2 gas yield and fuel combustion efficiency were calculated based on the flue gas composition. The CO2 gas yield was 93.8% and the fuel combustion efficiency was 96.0%, thus the conversion and combustion index Icombustion was 3.

[0141] (3) Energy dispersive spectroscopy (EDS) spectra of the oxygen support before and after the reaction were obtained and X-ray diffraction analysis was performed. It was found that the surface of the fresh oxygen support was covered with fine particles, resulting in a high specific surface area. However, although the specific surface area decreased in the initial run of the experiment, it maintained a relatively stable structure in subsequent experiments. Specifically, the elemental changes before and after the reaction were no more than 80%, and the spectral values ​​of the same elements before and after the reaction changed no more than 60%. The lifetime index I was obtained. life The value is 4.

[0142] (4) Calculate the performance index value I of the oxygen carrier according to the formula.

[0143] I = 0.2Iexhaust + 0.5Icombustion + 0.3Ilife = 0.2*3 + 0.5*3 + 0.3*4 = 3.3, meaning the obtained oxygen carrier performance index value is within the range and needs further optimization.

[0144] (5) Analysis of the performance index value I of the oxygen carrier revealed that the conversion and combustion index value Icombustion was less than the set conversion and combustion value, i.e., the optimal value of 4 was not reached. Therefore, when preparing the Cu-based oxygen carrier, an appropriate amount of Ni was added. Specifically, the mass of Ni could be 0.1 times the mass of Cu.

[0145] Testing has shown that the oxygen carrier performance evaluation and optimization method for carbon capture described in this invention can not only accurately evaluate the performance of oxygen carriers in practical applications, but also use the evaluation results to guide the preparation of oxygen carriers.

[0146] Example 3

[0147] The implementation follows the same procedure as Example 1, but differs in that it is used to evaluate the performance of Fe-Cu mixed-based oxygen carriers in practical applications:

[0148] (1) A Redox cycle was carried out 100 times in a fixed-bed reactor. The fluidizing gas was a N2 / CO2 mixture with a concentration ratio of 8:2 and a total gas flow rate of 10 L / min. The fuel gas mainly consisted of methane, ethane, and propane, with concentrations of 87.31%, 4.17%, and 1.78%, respectively. The reaction temperature was 900℃ and the reaction pressure was atmospheric pressure. Taking 900℃ as an example, the CO2 emission concentration was 95% and the NOx concentration was less than 30 mg / m³. 3 The emission index Iexhaust was found to be 4.

[0149] (2) The CO2 gas yield and fuel combustion efficiency were calculated based on the flue gas composition. The CO2 gas yield was 90% and the fuel combustion efficiency was 97.4%, thus the conversion and combustion index Icombustion was 4.

[0150] (3) Energy dispersive spectroscopy (EDS) spectra of the oxygen support before and after the reaction were obtained and X-ray diffraction analysis was performed. It was found that the surface of the fresh oxygen support was covered with fine particles, resulting in a high specific surface area. However, although the specific surface area decreased in the initial run of the experiment, it maintained a relatively stable structure in subsequent experiments. Specifically, the elemental changes before and after the reaction were no more than 80%, and the spectral values ​​of the same elements before and after the reaction changed no more than 60%. The lifetime index I was obtained. life The value is 4.

[0151] (4) Calculate the performance index value I of the oxygen carrier according to the formula.

[0152] I = 0.2Iexhaust + 0.5Icombustion + 0.3Ilife = 0.2*4 + 0.5*4 + 0.3*4 = 4.0, meaning the obtained oxygen carrier performance index value is excellent and no optimization is required;

[0153] Testing has shown that the oxygen carrier performance evaluation and optimization method for carbon capture described in this invention can not only accurately evaluate the performance of oxygen carriers in practical applications, but also use the evaluation results to guide the preparation of oxygen carriers.

[0154] The carbon capture oxygen carrier performance evaluation and optimization method and system provided by this invention obtains the emission index values, conversion and combustion index values, and lifetime index values ​​of the oxygen carrier in actual application, and further obtains the performance index values ​​of the oxygen carrier based on these emission index values, conversion and combustion index values, and lifetime index values. This not only enables accurate evaluation of the oxygen carrier performance, but also allows the evaluation results to be used to guide the preparation of the oxygen carrier.

[0155] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention. To avoid unnecessary repetition, the present invention will not describe all possible combinations separately. However, these simple modifications and combinations should also be considered as part of the content disclosed in this invention and are all within the protection scope of this invention.

Claims

1. A method for performance evaluation and optimization of oxygen carriers for carbon capture, characterized in that, The method for evaluating and optimizing the performance of oxygen carriers for carbon capture includes the following steps: S1. Based on a fixed-bed reactor, multiple Redox cycles were carried out to analyze the average concentrations of NOx and CO2 in the flue gas and obtain the emission index values. S2. Calculate the CO2 gas yield in the flue gas and the combustion efficiency of the fuel, and obtain the conversion and combustion index values ​​based on the CO2 gas yield in the flue gas and the combustion efficiency of the fuel. S3. Obtain the energy spectrum of the oxygen support before and after the reaction and conduct X-ray diffraction analysis. Based on the specific surface area of ​​the oxygen support before and after the reaction and the spectrum of the same element, obtain the lifetime index value. S4. Based on the obtained emission index values, conversion and combustion index values, and lifespan index values, calculate the performance index values ​​of the oxygen carrier, and optimize the performance of the oxygen carrier based on the performance index values ​​of the oxygen carrier.

2. The method for performance evaluation and optimization of oxygen carriers for carbon capture according to claim 1, characterized in that, In step S1, the average concentrations of NOx and CO2 in the flue gas are analyzed to obtain the emission index value Iexhaust, specifically including: When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the CO2 concentration percentage is greater than or equal to 95%, the Iexhaust value is 4; When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the percentage of CO2 concentration is greater than or equal to 90% and less than or equal to 95%, Iexhaust is 3; When the NOx concentration in the flue gas is less than or equal to 30 mg / m³ 3 When the CO2 concentration percentage is less than 90%, Iexhaust is 2; When the NOx concentration in the flue gas is greater than 30 mg / m³ 3 When the CO2 concentration percentage is less than 90%, Iexhaust is 1.

3. The method for performance evaluation and optimization of oxygen carriers for carbon capture according to claim 1, characterized in that, In step S2, the formula for calculating the CO2 gas yield in the flue gas is: Where Yco2 is the CO2 gas yield; Cco2,out is the volume fraction of CO2 in the flue gas measured at a certain time; Vout is the flue gas volume measured at a certain time; and Cco,out is the volume fraction of CO in the flue gas measured at a certain time. The volume fraction of CH4 in the flue gas measured at a certain moment; The volume fraction of C2H6 in the flue gas measured at a certain moment; The volume fraction of C3H8 in the flue gas measured at a certain moment.

4. The method for performance evaluation and optimization of oxygen carriers for carbon capture according to claim 1 or 3, characterized in that, In step S2, the formula for calculating the fuel combustion efficiency is: Where, η c For fuel combustion efficiency; F out,red yco is the exhaust gas flow rate during the reduction stage; Hco is the lower heating value of CO; Mco is the molar mass of CO; yco is the volume fraction of CO in the flue gas; H CH4 The lower heating value of CH4; M CH4 y is the molar mass of CH4; CH4 H represents the volume fraction of CH4 in the flue gas. H2 The lower heating value of H2; M H2 y is the molar mass of H2; H2 The volume fraction of H2 in the flue gas; Hc is the lower heating value of the gas in the oxidation stage; Mc is the molar mass of the gas in the oxidation stage; Nc,ox is the mass of the gas in the oxidation stage; m fuel For fuel mass; H fuel It represents the lower heating value of the fuel.

5. The method for performance evaluation and optimization of oxygen carrier for carbon capture according to claim 1 or 3, characterized in that, In step S2, obtaining the conversion and combustion index value Icombustion based on the CO2 gas yield in the flue gas and the fuel combustion efficiency specifically includes: When the CO2 gas yield in the flue gas is greater than or equal to 90% and the fuel combustion efficiency is greater than or equal to 97%, Icombustion is 4. When the CO2 gas yield in the flue gas is greater than or equal to 88% and the fuel combustion efficiency is greater than or equal to 93%, Icombustion is 3; When the CO2 gas yield in the flue gas is greater than or equal to 80% and the fuel combustion efficiency is greater than or equal to 90%, Icombustion is 2. When the CO2 gas yield in the flue gas and the fuel combustion efficiency are not as described above, Icombustion is 1.

6. The method for performance evaluation and optimization of oxygen carriers for carbon capture according to claim 1, characterized in that, In step S3, the lifetime index value I is obtained based on the specific surface area of ​​the oxygen carrier before and after the reaction and the spectra of the same elements. life Specifically, it includes: When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 80%, and the change in the spectral value of the same element is no greater than 60%, I life It is 4; When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 60%, and the change in the spectral value of the same element is no greater than 60%, I life It is 3; When the change in the specific surface area of ​​the oxygen carrier before and after the reaction is no greater than 80%, and the change in the spectral value of the same element is no greater than 50%, I life It is 2; When the changes in the specific surface area of ​​the oxygen support and the spectral values ​​of the same elements before and after the reaction are not as described above, I life The value is 1.

7. The method for performance evaluation and optimization of oxygen carriers for carbon capture according to claim 1, characterized in that, In step S4, the formula for calculating the performance index value of the oxygen carrier is: I=0.2Iexhaust+0.5Icombustion+0.3I life Where I represents the performance index value of the oxygen carrier, Iexhaust represents the emission index value, Icombustion represents the conversion and combustion index value, and I... life This refers to lifespan index values.

8. The method for performance evaluation and optimization of oxygen carriers for carbon capture according to claim 1 or 7, characterized in that, In step S4, optimizing the performance of the oxygen carrier based on its performance index values ​​specifically includes: When the performance index value of the oxygen carrier is less than the set performance value, if the conversion and combustion index value is less than the set conversion and combustion value and / or the life index value is less than the set life value, then the oxygen carrier substrate should be optimized during the preparation of the oxygen carrier.

9. The method for performance evaluation and optimization of oxygen carrier for carbon capture according to claim 8, characterized in that, Also includes: If the performance index of the oxygen carrier is not less than the set value, there is no need to optimize the performance of the oxygen carrier.

10. The method for performance evaluation and optimization of oxygen carriers for carbon capture according to claim 1, characterized in that, The Redox cycle is 80-120 times.

11. The method for performance evaluation and optimization of oxygen carrier for carbon capture according to claim 1, characterized in that, The oxygen carrier is a metal-based oxygen carrier.

12. A performance evaluation and optimization system for oxygen carriers used in carbon capture, characterized in that, The performance evaluation and optimization system, applied to the performance evaluation and optimization method according to any one of claims 1-11, comprises: The emission index value acquisition module is used to perform multiple Redox cycles based on a fixed-bed reactor, analyze the average concentrations of NOx and CO2 in the flue gas, and obtain emission index values. The conversion and combustion index value acquisition module is used to calculate the CO2 gas yield and fuel combustion efficiency in flue gas, and obtain the conversion and combustion index values ​​based on the CO2 gas yield and fuel combustion efficiency in flue gas. The lifetime index value acquisition module is used to acquire the energy spectrum of the oxygen carrier before and after the reaction and to carry out X-ray diffraction analysis. Based on the specific surface area of ​​the oxygen carrier before and after the reaction and the spectrum of the same element, the lifetime index value is obtained. The performance index value acquisition and optimization module is used to calculate the performance index value of the oxygen carrier based on the obtained emission index value, conversion and combustion index value and lifespan index value, and to optimize the performance of the oxygen carrier based on the performance index value.

13. An electronic device, characterized in that, It includes at least one processor, at least one memory, and a communication interface; the processor, the memory, and the communication interface communicate with each other; the memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the performance evaluation and optimization method according to any one of claims 1-11.

14. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions that enable the machine-readable storage medium to execute the performance evaluation and optimization method according to any one of claims 1-11.

Images