Method and system for optimization of municipal and industrial solid waste thermal treatment and carbon capture process

Abstract

The application discloses a method and system for optimizing a process of heat treatment and carbon capture of urban and industrial solid wastes, and belongs to the technical field of comprehensive treatment of solid waste resources. The application is used for solving the problem of process optimization of carbon emission reduction in the process of solid waste resource utilization. The application comprises the following steps: calculating a benchmark pyrolysis gas mass flow; determining a gas phase distribution factor at a heat treatment-gasification inlet; calculating a mass flow of products determined by thermodynamics and empirical distribution; then, by introducing an effective molar concentration to describe the generation rate of each product, a product mass flow based on a kinetic model is calculated; introducing exergy analysis to evaluate the loss of available energy, so as to obtain the total exergy efficiency of the heat treatment-gasification section; considering that the carbon-containing gas generated by the heat treatment-gasification is connected with a downstream carbon capture unit, the total energy consumption of the carbon capture process is calculated; the capture rate of CO2 and the energy consumption per capture are calculated; and a comprehensive objective function is constructed, which is used for determining the optimal heat treatment, gasification and carbon capture parameters of urban and industrial solid wastes.

Description

Technical Field

[0001] This invention belongs to the field of integrated treatment technology for solid waste resource utilization, specifically involving optimization methods and systems for thermal treatment and carbon capture processes of urban and industrial solid waste. Background Technology

[0002] With urbanization and industrialization, the production of various types of solid waste, including municipal solid waste, sludge, general industrial solid waste, and some hazardous waste, is constantly increasing. Traditional landfilling or simple incineration methods consume large amounts of land resources and generate leachate and acidic gases. Therefore, using thermal treatment methods such as pyrolysis or gasification to reduce, render harmless, and utilize the resources of solid waste generated by cities and industries has become an important development trend.

[0003] However, energy recovery through heat treatment and gasification alone still results in a large amount of CO2 and other carbon-containing gases. Under the constraints of "dual carbon," simply improving furnace efficiency is no longer sufficient to achieve emission reduction. It is also necessary to combine urban and industrial solid waste heat treatment processes with carbon capture technology. Summary of the Invention

[0004] The problem this invention aims to solve is the optimization of carbon emission reduction processes in the utilization of solid waste resources. It proposes methods and systems for optimizing the thermal treatment and carbon capture processes of urban and industrial solid waste.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] An optimization method for urban and industrial solid waste thermal treatment and carbon capture processes includes the following steps:

[0007] S1. Calculate the baseline pyrolysis gas mass flow rate based on the initial mass flow rate of urban and industrial solid waste raw materials and the mass fraction of each element contained therein;

[0008] S2. Establish the pyrolysis gas generation ratio, correct the baseline pyrolysis gas mass flow rate obtained in step S1, and obtain the corrected pyrolysis gas mass flow rate; determine the gas phase distribution factor at the heat treatment-gasification inlet, taking into account the characteristic that high molecular weight substances in solid waste are prone to tar formation.

[0009] S3. Based on the corrected pyrolysis gas mass flow rate obtained in step S1, calculate the product mass flow rate determined by thermodynamics and empirical distribution; then, by introducing the effective molar concentration to describe the generation rate of each product, calculate the product mass flow rate based on the kinetic model.

[0010] S4. Based on the mass flow rate of the product obtained in step S3, calculate the mass flow rate of urban and industrial solid waste raw materials in reverse; introduce energy analysis to assess available energy loss and obtain the total energy efficiency of the heat treatment-gasification section.

[0011] S5. Consider connecting the carbon-containing gas generated by heat treatment-gasification to the downstream carbon capture unit and calculate the total cycle energy consumption of the carbon capture process; consider the separation efficiency of the capture equipment and calculate the CO2 capture rate and unit CO2 capture energy consumption.

[0012] S6. Considering the overall efficiency of the heat treatment-gasification section obtained in step S4, the CO2 capture rate obtained in step S5, the environmental impact index, and the thermodynamic-kinetic consistency measure as evaluation criteria, a comprehensive objective function is constructed to determine the optimal heat treatment parameters for urban and industrial solid waste, including heat treatment, gasification, and carbon capture.

[0013] Furthermore, step S1 obtains the baseline pyrolysis gas mass flow rate by weighted summing of the initial urban and industrial solid waste raw materials and the mass fraction of each element contained therein, and by introducing an equivalent ratio correction term to unify the scale of organic matter, oxygen content, and oxygen supply intensity in the solid waste. .

[0014] Furthermore, the specific implementation method of step S2 includes the following steps:

[0015] S2.1. Using the equivalence ratio and the bounded proportion term with normalized temperature as independent variables, we can achieve the equivalent conversion of the degree of pyrolysis and oxygen supply intensity into the pyrolysis gas generation ratio, resulting in:

[0016]

[0017] in, The ratio of pyrolysis gas generated; ER is the equivalence ratio, that is, the ratio of actual oxygen supply to stoichiometric oxygen supply; This is a reference temperature, set by professionals; T is the pyrolysis temperature. , , These are the equivalence ratio parameter, temperature parameter, and pyrolysis correction parameter, which are set by professionals.

[0018] S2.2. Correct the reference pyrolysis gas mass flow rate using the pyrolysis gas generation ratio to obtain the corrected pyrolysis gas mass flow rate. , ;

[0019] S2.3. Based on the tar-related apparent activation energy, temperature, and equivalence ratio, a bounded factor is established to convert the synergistic effect of high temperature promoting tar cracking and oxidation-assisted combustion into the degree of gas phase partitioning. The gas phase partitioning factor at the heat treatment-gasification inlet is then determined, yielding:

[0020]

[0021] in, It is the gas phase partition factor; The apparent activation energy related to tar was obtained from the literature. , These are the tar formation baseline coefficient and the oxygen supply influence coefficient, respectively, determined by experiments, literature, or professionals; R is the universal gas constant, obtained from literature.

[0022] Furthermore, the specific implementation method of step S3 includes the following steps:

[0023] S3.1. Establish a thermodynamic-empirical generation tendency value that simultaneously reflects the thermodynamic equilibrium trend, the effects of temperature and vaporization pressure, and empirical corrections, whereby... Let p be the thermodynamic-empirical formation tendency value of product p. It is the vaporization temperature. The vaporization pressure;

[0024] Then, using the corrected pyrolysis gas mass flow rate obtained in step S1 as a benchmark, the mass flow rate of product p, determined by thermodynamics and empirical distribution, is calculated. The calculation formula is:

[0025]

[0026] in, It is a collection of typical products;

[0027] S3.2. Correlate the gas phase partition factor obtained in step S1 with the mixed gas volumetric flow rate and average molar mass to establish the effective molar concentration, expressed as:

[0028]

[0029] in, Effective molar concentration; The volumetric flow rate of the mixed gas. The average molar mass of the mixture is obtained from experimental calculations.

[0030] Then, the formation rate of each typical product is described in exponential form with temperature as the independent variable, and the expression is:

[0031]

[0032] in, The formation rate of product p; The apparent activation energy of product p is obtained from the literature; The rate constant factor for product p is determined by technical personnel.

[0033] Then, the product mass flow rate based on the kinetic model is calculated using the following formula:

[0034]

[0035] in, The mass flow rate of product p is calculated from the kinetic model; These are measurement correction factors, determined by literature or professionals; The molar mass of product p is determined from the literature; The effective volume of the reactor is obtained from the design specifications; The time unit conversion factor is determined by professionals.

[0036] Furthermore, the specific implementation method of step S4 includes the following steps:

[0037] S4.1. By multiplying and summing the mass flow rates of each product by its lower heating value, and combining this with the combustion efficiency and the lower heating value of the raw materials, the mass flow rates of municipal and industrial solid waste raw materials are calculated in reverse. The calculation formula is:

[0038]

[0039] in, Mass flow rate of urban and industrial solid waste raw materials; The lower heating value of product p is determined by literature; Combustion efficiency is determined by testing, literature, or professional expertise. The lower calorific value of mixed urban and industrial solid waste raw materials shall be determined by testing or professional personnel.

[0040] S4.2. The damage rate caused by mixing, irreversible reaction, and heat transfer is quantified by weighted summation of the differences between the product specific entropy and the reference specific entropy. The calculation formula is as follows:

[0041]

[0042] in, The destruction rate; The specific entropy of product p is obtained from the literature; The baseline state entropy is determined by literature or professionals. This is a reference temperature, set by a professional.

[0043] Then, by calculating the product ratio multiplied by the mass flow rate, subtracting the energy destruction rate, and comparing it with the total energy input, the overall energy efficiency of the heat treatment-gasification section, taking into account both energy quantity and quality, is obtained. .

[0044] Furthermore, the specific implementation method of step S5 includes the following steps:

[0045] S5.1. The total cycle energy consumption of carbon capture is calculated by integrating the power of the adsorption stage and the power of the desorption stage over statistical time Δt. ;

[0046] S5.2. Set the mass flow rate of product p obtained in step S3. The obtained CO2 mass flow rate To determine the CO2 mass flow rate entering the capture unit, the mass flow rate of successfully captured CO2 is obtained, taking into account the separation efficiency of the capture equipment. The CO2 capture rate is then calculated. ;

[0047] Then, the total energy consumption per cycle of carbon capture is divided by the mass flow rate of CO2 successfully captured to obtain the energy consumption per unit of CO2 capture. .

[0048] Furthermore, the expression for the comprehensive objective function constructed in step S6 is as follows:

[0049]

[0050] in, The value of the comprehensive objective function; ~ These are the efficiency weight, carbon capture weight, environmental impact weight, and model consistency weight, which are determined by literature or professionals. For comprehensive environmental impact indicators; This is a thermodynamic-kinetic consistency penalty term;

[0051] Then establish and The relationship is ;

[0052] Change the equivalence ratio ER, pyrolysis temperature T, and gasification pressure vaporization temperature Mixed gas volume flow rate Multiple test conditions were set up, and the optimal heat treatment parameters for urban and industrial solid waste were determined by calculating the comprehensive objective function value Z under different conditions.

[0053] A system for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste includes a processor, a memory, and a computer program stored in the memory and executable on the processor. When the computer program is executed, it implements the steps of the optimized thermal treatment and carbon capture process of urban and industrial solid waste.

[0054] The beneficial effects of this invention are:

[0055] The present invention describes an optimization method for the thermal treatment and carbon capture process of urban and industrial solid waste. Through a unified material, energy and flow analysis framework, it performs overall correlation calculations on each stage of urban and industrial solid waste thermal treatment-gasification and carbon capture, resulting in more reasonable results. It can simultaneously evaluate energy utilization efficiency, carbon emission reduction and environmental impact, and provide a reference for engineers to select different process routes or operating conditions.

[0056] The present invention describes an optimization method for urban and industrial solid waste thermal treatment and carbon capture processes. By quantifying the material flow conversion efficiency and loss distribution of the entire system, the thermal treatment emissions and carbon capture costs are incorporated into the same energy benchmark for comprehensive evaluation. A multi-objective decision function is constructed to select the optimal process parameter configuration scheme. Attached Figure Description

[0057] Figure 1 This is a flowchart of an optimization method for urban and industrial solid waste thermal treatment and carbon capture processes according to the present invention. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described specific embodiments are merely a part of the embodiments of the invention, and not all of them. The components of the specific embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations, and the invention may also have other embodiments.

[0059] Therefore, the following detailed description of specific embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected specific embodiments of the invention. All other specific embodiments obtained by those skilled in the art based on these specific embodiments without inventive effort are within the scope of protection of this invention.

[0060] To further understand the invention's content, features, and effects, the following specific embodiments are provided, along with accompanying drawings. Figure 1 Detailed explanation is as follows:

[0061] Example 1:

[0062] An optimization method for urban and industrial solid waste thermal treatment and carbon capture processes includes the following steps:

[0063] S1. Calculate the baseline pyrolysis gas mass flow rate based on the initial mass flow rate of urban and industrial solid waste raw materials and the mass fraction of each element contained therein;

[0064] Furthermore, step S1 obtains the baseline pyrolysis gas mass flow rate by weighted summing of the initial urban and industrial solid waste raw materials and the mass fraction of each element contained therein, and by introducing an equivalent ratio correction term to unify the scale of organic matter, oxygen content, and oxygen supply intensity in the solid waste. The calculation formula is:

[0065]

[0066]

[0067] in, The reference pyrolysis gas mass flow rate; The initial mass flow rate of urban and industrial solid waste raw materials is determined directly by professionals based on the scale of the raw materials. , , These are the mass fractions of carbon, hydrogen, and oxygen in urban and industrial solid waste, respectively, obtained through elemental analysis. This is an equivalence ratio correction term, determined by literature or professionals; , , These are the conversion coefficients for carbon, hydrogen, and oxygen, respectively. This is the equivalent ratio correction factor, determined by literature or professionals; This is a pyrolysis correction term; The apparent enthalpy characteristic of pyrolysis was obtained from the literature. These are universal gas constants, obtained from literature; This is a reference temperature for pyrolysis characteristics, set by professionals. The initial value of the pyrolysis temperature is determined by professionals and serves as a decision variable for multi-objective optimization. Its optimal value is determined by multi-objective optimization in step S6.

[0068] Furthermore, in the high-temperature pyrolysis process of urban and industrial solid waste, it is first necessary to determine the amount of gaseous products generated under specific raw material composition and oxygen supply. This step involves weighted summation of the mass flow rate of the raw material and the mass fraction of each element, and introducing an equivalent ratio correction term to standardize the metrics for organic matter, oxygen content, and oxygen supply intensity in the solid waste.

[0069] Simultaneously, dimensionless coefficients related to the apparent enthalpy of pyrolysis, apparent activation energy, and temperature are used to characterize the transition state of pyrolysis from partial decomposition to complete decomposition, thereby calculating the baseline pyrolysis gas mass flow rate:

[0070] S2. Establish the pyrolysis gas generation ratio, correct the baseline pyrolysis gas mass flow rate obtained in step S1, and obtain the corrected pyrolysis gas mass flow rate; determine the gas phase distribution factor at the heat treatment-gasification inlet, taking into account the characteristic that high molecular weight substances in solid waste are prone to tar formation.

[0071] Considering the nonlinear influence of equivalence ratio and temperature on actual pyrolysis gas generation, this step constructs a bounded proportionality term with equivalence ratio and normalized temperature as independent variables. This term equivalently converts the degree of pyrolysis and oxygen supply intensity into a gas generation ratio, enabling the model to adapt to the transition from mild pyrolysis to enhanced gasification conditions. Based on this, the baseline pyrolysis gas flow rate is adjusted.

[0072] Furthermore, the specific implementation method of step S2 includes the following steps:

[0073] S2.1. Using the equivalence ratio and the bounded proportion term with normalized temperature as independent variables, we can achieve the equivalent conversion of the degree of pyrolysis and oxygen supply intensity into the pyrolysis gas generation ratio, resulting in:

[0074]

[0075] in, The pyrolysis gas generation ratio is ER; ER is the equivalence ratio, which is the ratio of actual oxygen supply to stoichiometric oxygen supply. Its initial value is determined by professionals and serves as a decision variable for multi-objective optimization. Its optimal value is determined by multi-objective optimization in step S6. This is a reference temperature, set by professionals; T is the pyrolysis temperature. , , These are the equivalence ratio parameter, temperature parameter, and pyrolysis correction parameter, which are set by professionals.

[0076] S2.2. Correct the reference pyrolysis gas mass flow rate using the pyrolysis gas generation ratio to obtain the corrected pyrolysis gas mass flow rate. , ;

[0077] S2.3. Based on the tar-related apparent activation energy, temperature, and equivalence ratio, a bounded factor is established to convert the synergistic effect of high temperature promoting tar cracking and oxidation-assisted combustion into the degree of gas phase partitioning. The gas phase partitioning factor at the heat treatment-gasification inlet is then determined, yielding:

[0078]

[0079] in, It is the gas phase partition factor; The apparent activation energy related to tar was obtained from the literature. , These are the tar formation baseline coefficient and the oxygen supply influence coefficient, respectively, determined by experiments, literature, or professionals; R is the universal gas constant, obtained from literature.

[0080] Furthermore, considering the tendency of high molecular weight substances in solid waste to generate tar, this step proposes a bounded factor composed of tar-related apparent activation energy, temperature, and equivalence ratio. This factor transforms the synergistic effect of high temperature promoting tar cracking and oxidation-assisted combustion into the degree of gas phase partitioning, thereby determining the gas phase partitioning factor at the heat treatment-gasification inlet.

[0081] S3. Based on the corrected pyrolysis gas mass flow rate obtained in step S1, calculate the product mass flow rate determined by thermodynamics and empirical distribution; then, by introducing the effective molar concentration to describe the generation rate of each product, calculate the product mass flow rate based on the kinetic model.

[0082] Furthermore, the specific implementation method of step S3 includes the following steps:

[0083] S3.1. Establish a thermodynamic-empirical generation tendency value that simultaneously reflects the thermodynamic equilibrium trend, the effects of temperature and vaporization pressure, and empirical corrections, whereby... Let p be the thermodynamic-empirical formation tendency value of product p. It is the vaporization temperature. The vaporization pressure;

[0084] Furthermore, based on the total gas flow rate obtained from pyrolysis-gas phase distribution, the distribution of each component needs to be further analyzed to predict syngas characteristics and carbon capture load. First, a typical product set is defined:

[0085] ;

[0086] Based on the total flow rate, a generation tendency value that simultaneously reflects the thermodynamic equilibrium trend, temperature and pressure effects, and empirical corrections is introduced. The mass flow rate of product p, determined by thermodynamics and empirical distribution, is calculated as follows:

[0087]

[0088] in, The thermodynamic-empirical formation tendency value of product p; The empirical coefficient for product p is determined by professionals. The Gibbs characteristic of product p is obtained from literature or determined by professionals. The initial value of the vaporization pressure is determined by professionals and serves as a decision variable for multi-objective optimization. Its optimal value is determined by multi-objective optimization in step S6. The initial value of the vaporization temperature is determined by professionals and serves as a decision variable for multi-objective optimization. Its optimal value is determined by multi-objective optimization in step S6. These are normalized temperature reference values, determined by professionals. , These are pressure correction parameters and temperature correction parameters, determined by professionals.

[0089] Then, using the corrected pyrolysis gas mass flow rate obtained in step S1 as a benchmark, the mass flow rate of product p, determined by thermodynamics and empirical distribution, is calculated. The calculation formula is:

[0090]

[0091] in, It is a collection of typical products;

[0092] S3.2. Correlate the gas phase partition factor obtained in step S1 with the mixed gas volumetric flow rate and average molar mass to establish the effective molar concentration, expressed as:

[0093]

[0094] in, Effective molar concentration; The initial value of the mixed gas volume flow rate is determined by professionals and serves as a decision variable for multi-objective optimization. Its optimal value is determined by multi-objective optimization in step S6. The average molar mass of the mixture is obtained from experimental calculations.

[0095] Furthermore, to address the difficulties in describing the kinetics caused by the complexity of solid waste sources, this step introduces the concept of effective molar concentration;

[0096] Then, the formation rate of each typical product is described in exponential form with temperature as the independent variable, and the expression is:

[0097]

[0098] in, The formation rate of product p; The apparent activation energy of product p is obtained from the literature; The rate constant factor for product p is determined by technical personnel.

[0099] Then, the product mass flow rate based on the kinetic model is calculated using the following formula:

[0100]

[0101] in, The mass flow rate of product p is calculated from the kinetic model; These are measurement correction factors, determined by literature or professionals; The molar mass of product p is determined from the literature; The effective volume of the reactor is obtained from the design specifications; The time unit conversion factor is determined by professionals; it ensures the consistency of thermodynamic distribution and kinetic rate on an engineering scale and provides physical constraints for multi-objective optimization.

[0102] S4. Based on the mass flow rate of the product obtained in step S3, calculate the mass flow rate of urban and industrial solid waste raw materials in reverse; introduce energy analysis to assess available energy loss and obtain the total energy efficiency of the heat treatment-gasification section.

[0103] Furthermore, the specific implementation method of step S4 includes the following steps:

[0104] S4.1. By multiplying and summing the mass flow rates of each product by its lower heating value, and combining this with the combustion efficiency and the lower heating value of the raw materials, the mass flow rates of municipal and industrial solid waste raw materials are calculated in reverse. The calculation formula is:

[0105]

[0106] in, Mass flow rate of urban and industrial solid waste raw materials; The lower heating value of product p is determined by literature; Combustion efficiency is determined by testing, literature, or professional expertise. The lower calorific value of mixed urban and industrial solid waste raw materials shall be determined by testing or professional personnel.

[0107] Furthermore, after obtaining the product mass flow rate of the heat treatment-gasification stage, in order to compare different operating conditions under a unified energy standard, it is necessary to multiply and sum the mass flow rate of each product with its lower heating value, and combine the combustion efficiency and the lower heating value of the raw material to calculate the mass flow rate of urban and industrial solid waste raw materials required to maintain the process.

[0108] Based on this, simply considering energy conservation is insufficient to reflect the available energy loss of urban and industrial solid waste during the heat treatment-gasification process. Therefore, energy analysis is further introduced to assess the available energy loss.

[0109] S4.2. The damage rate caused by mixing, irreversible reaction, and heat transfer is quantified by weighted summation of the differences between the product specific entropy and the reference specific entropy. The calculation formula is as follows:

[0110]

[0111] in, The destruction rate; The specific entropy of product p is obtained from the literature; The baseline state entropy is determined by literature or professionals. This is a reference temperature, set by a professional.

[0112] Then, by calculating the product ratio multiplied by the mass flow rate, subtracting the energy destruction rate, and comparing it with the total energy input, the overall energy efficiency of the heat treatment-gasification section, taking into account both energy quantity and quality, is obtained. The performance of urban and industrial solid waste heat treatment-gasification processes is comprehensively evaluated from the perspective of available energy, and the calculation formula is as follows:

[0113]

[0114] in, The total efficiency of the heat treatment-gasification section; The total input for the heat treatment-gasification section should be determined by references or professionals. The ratio of product A is determined by literature or professionals.

[0115] S5. Consider connecting the carbon-containing gas generated by heat treatment-gasification to the downstream carbon capture unit and calculate the total cycle energy consumption of the carbon capture process; consider the separation efficiency of the capture equipment and calculate the CO2 capture rate and unit CO2 capture energy consumption.

[0116] Furthermore, the specific implementation method of step S5 includes the following steps:

[0117] S5.1. The total cycle energy consumption of carbon capture is calculated by integrating the power of the adsorption stage and the power of the desorption stage over statistical time Δt. ;

[0118] Furthermore, based on the energy and cost analysis of the urban and industrial solid waste thermal treatment-gasification stage, it is also necessary to calculate the total energy cost. By connecting the carbon-containing gas generated from thermal treatment-gasification to the downstream carbon capture unit, and integrating the power of the adsorption stage and the power of the desorption stage over statistical time Δt, the total cycle energy consumption of carbon capture is calculated.

[0119]

[0120] in, The total energy consumption per cycle for carbon capture; The adsorption stage power is determined by equipment data acquisition or by professionals. The power output during the desorption stage is determined by equipment data acquisition or by professionals. The statistical timeframe was determined by professionals.

[0121] S5.2. Set the mass flow rate of product p obtained in step S3. The obtained CO2 mass flow rate To determine the CO2 mass flow rate entering the capture unit, the mass flow rate of successfully captured CO2 is obtained, taking into account the separation efficiency of the capture equipment. The CO2 capture rate is then calculated. ;

[0122] Furthermore, in terms of material balance, the mass flow rate of CO2 obtained from the product vector is the CO2 inlet flow rate entering the capture device. Considering the separation efficiency of the capture device, the mass flow rate of successfully captured CO2 can be obtained, thus yielding the capture rate. This parameter divides the carbon emissions generated during the pyrolysis-gasification process of urban and industrial solid waste into the intercepted portion and the uncaptured portion, quantifying the carbon emission reduction capacity. The expression is:

[0123] ,

[0124] in, The CO2 capture rate; The mass flow rate of captured CO2 was determined experimentally. This refers to the CO2 mass flow rate entering the collection unit; The mass flow rate of CO2, obtained from thermodynamic and empirical distribution, is determined by step S3. We obtain that p = CO2;

[0125] Then, the total energy consumption per cycle of carbon capture is divided by the mass flow rate of CO2 successfully captured to obtain the energy consumption per unit of CO2 capture. ;

[0126] Furthermore, in the comprehensive benefit analysis, it is impossible to directly compare different carbon capture processes, operating conditions, or urban and industrial solid waste supply based solely on total energy consumption and capture volume. To facilitate horizontal comparison, the energy consumption per unit of CO2 capture is calculated by dividing the total energy consumption per cycle by the mass of CO2 captured, serving as one of the evaluation indicators for multi-objective optimization. The expression is as follows:

[0127]

[0128] in, Energy consumption per unit of CO2 capture.

[0129] S6. Considering the overall efficiency of the heat treatment-gasification section obtained in step S4, the CO2 capture rate obtained in step S5, the environmental impact index, and the thermodynamic-kinetic consistency measure as evaluation criteria, a comprehensive objective function is constructed to determine the optimal heat treatment parameters for urban and industrial solid waste, including heat treatment, gasification, and carbon capture.

[0130] Furthermore, the expression for the comprehensive objective function constructed in step S6 is as follows:

[0131]

[0132] in, The value of the comprehensive objective function; ~ These are the efficiency weight, carbon capture weight, environmental impact weight, and model consistency weight, which are determined by literature or professionals. For comprehensive environmental impact indicators; This is a thermodynamic-kinetic consistency penalty term;

[0133] Then establish and The relationship is Considering the actual mass flow rate of urban and industrial solid waste raw materials processed. The theoretical requirement to meet the mass flow rate needs to be met. This is to ensure that the actual processing capacity of the system can reach the set target;

[0134] Furthermore, in the entire process of urban and industrial solid waste thermal treatment-gasification-carbon capture, multiple objectives such as resource utilization, carbon capture rate, and environmental impact often need to be balanced. Therefore, using total energy efficiency, CO2 capture rate, environmental impact indicators, and thermodynamic-kinetic consistency measures as evaluation criteria, a weighted objective function is constructed. Different weights are assigned to various evaluation criteria in different urban or industrial scenarios to reflect the degree of importance people attach to energy efficiency, emission reduction, environment, and model reliability.

[0135] Furthermore, in terms of comprehensive environmental impact, it is necessary to simultaneously consider uncaptured flue gas emissions, indirect emissions caused by energy consumption during the capture process, energy consumption per unit of CO2 capture, and the emission reduction effect brought about by captured carbon dioxide. Multiplying the mass flow rate of each gaseous product *r* by its corresponding unit environmental impact factor, and summing the effects of carbon capture energy consumption and capture volume, yields a comprehensive environmental impact value that can measure the emission burden and emission reduction benefits. This value is used to evaluate the degree of comprehensive environmental impact corresponding to different thermal treatment conditions, different capture methods, and different operating modes. The expression is:

[0136]

[0137] in, The environmental factor per unit of product p is determined by literature or professionals; , These are the energy consumption and environmental load factor and the carbon emission reduction contribution factor, respectively, which are determined by literature or professionals.

[0138] In multi-objective optimization, to prevent model parameters from solely pursuing the product flow rate and thus disrupting the intrinsic relationship between thermodynamics and kinetics, a consistency penalty term needs to be introduced. This is achieved by comparing thermodynamic and empirical allocations. The difference between the calculated mass flow rate and the mass flow rate based on kinetic rate, reactor characteristic volume, and time conversion factor, and the sum of squares over all products, can transform this physical inconsistency into an optimizable metric. This allows the model to maintain reasonable extrapolation capability under fluctuations in urban and industrial solid waste composition and changes in carbon capture configuration, as expressed in the following expression:

[0139] ;

[0140] Change the equivalence ratio ER, pyrolysis temperature T, and gasification pressure vaporization temperature Mixed gas volume flow rate Multiple test conditions were set up, and the optimal heat treatment parameters for urban and industrial solid waste were determined by calculating the comprehensive objective function value Z under different conditions.

[0141] Example 2:

[0142] A system for optimizing the process of thermal treatment and carbon capture of urban and industrial solid waste includes a processor, a memory, and a computer program stored in the memory and run on the processor. When the computer program is run, it implements the steps of the method for optimizing the process of thermal treatment and carbon capture of urban and industrial solid waste as described in Embodiment 1.

[0143] It should be noted that relational terms such as "first" and "second" are used merely 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.

[0144] Although this application has been described above with reference to specific embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of this application. In particular, as long as there is no structural conflict, the features in the specific embodiments disclosed in this application can be combined with each other in any way. The lack of an exhaustive description of these combinations in this specification is merely for the sake of brevity and resource conservation. Therefore, this application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste, characterized in that, Includes the following steps: S1. Calculate the baseline pyrolysis gas mass flow rate based on the initial mass flow rate of urban and industrial solid waste raw materials and the mass fraction of each element contained therein; S2. Establish the pyrolysis gas generation ratio, correct the baseline pyrolysis gas mass flow rate obtained in step S1, and obtain the corrected pyrolysis gas mass flow rate; determine the gas phase distribution factor at the heat treatment-gasification inlet, taking into account the characteristic that high molecular weight substances in solid waste are prone to tar formation. S3. Based on the corrected pyrolysis gas mass flow rate obtained in step S1, calculate the mass flow rate of the product determined by thermodynamics and empirical distribution; Then, by introducing the effective molar concentration to describe the generation rate of each product, the product mass flow rate based on the kinetic model is calculated. S4. Based on the mass flow rate of the product obtained in step S3, calculate the mass flow rate of urban and industrial solid waste raw materials in reverse; introduce energy analysis to assess available energy loss and obtain the total energy efficiency of the heat treatment-gasification section. S5. Consider connecting the carbon-containing gas generated by heat treatment-gasification to the downstream carbon capture unit and calculate the total cycle energy consumption of the carbon capture process; consider the separation efficiency of the capture equipment and calculate the CO2 capture rate and unit CO2 capture energy consumption. S6. Considering the overall efficiency of the heat treatment-gasification section obtained in step S4, the CO2 capture rate obtained in step S5, the environmental impact index, and the thermodynamic-kinetic consistency measure as evaluation criteria, a comprehensive objective function is constructed to determine the optimal heat treatment parameters for urban and industrial solid waste, including heat treatment, gasification, and carbon capture.

2. The method for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste according to claim 1, characterized in that, Step S1 involves weighting and summing the mass flow rates of the initial urban and industrial solid waste raw materials with the mass fractions of each element, and introducing an equivalent ratio correction term to unify the scales of organic matter, oxygen content, and oxygen supply intensity in the solid waste, thereby obtaining the baseline pyrolysis gas mass flow rate. .

3. The method for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste according to claim 2, characterized in that, The specific implementation method of step S2 includes the following steps: S2.

1. Using the equivalence ratio and the bounded proportion term with normalized temperature as independent variables, we can achieve the equivalent conversion of the degree of pyrolysis and oxygen supply intensity into the pyrolysis gas generation ratio, resulting in: ； in, The ratio of pyrolysis gas generated; ER is the equivalence ratio, that is, the ratio of actual oxygen supply to stoichiometric oxygen supply; This is a reference temperature, set by professionals; T is the pyrolysis temperature. , , These are the equivalence ratio parameter, temperature parameter, and pyrolysis correction parameter, which are set by professionals. S2.

2. Correct the reference pyrolysis gas mass flow rate using the pyrolysis gas generation ratio to obtain the corrected pyrolysis gas mass flow rate. , ; S2.

3. Based on the tar-related apparent activation energy, temperature, and equivalence ratio, a bounded factor is established to convert the synergistic effect of high temperature promoting tar cracking and oxidation-assisted combustion into the degree of gas phase partitioning. The gas phase partitioning factor at the heat treatment-gasification inlet is then determined, yielding: ； in, It is the gas phase partition factor; The apparent activation energy related to tar was obtained from the literature. , These are the tar formation baseline coefficient and the oxygen supply influence coefficient, respectively, determined by experiments, literature, or professionals; R is the universal gas constant, obtained from literature.

4. The method for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste according to claim 3, characterized in that, The specific implementation method of step S3 includes the following steps: S3.

1. Establish a thermodynamic-empirical generation tendency value that simultaneously reflects the thermodynamic equilibrium trend, the effects of temperature and vaporization pressure, and empirical corrections, whereby... Let p be the thermodynamic-empirical formation tendency value of product p. It is the vaporization temperature. The vaporization pressure; Then, using the corrected pyrolysis gas mass flow rate obtained in step S1 as a benchmark, the mass flow rate of product p, determined by thermodynamics and empirical distribution, is calculated. The calculation formula is: ； in, It is a collection of typical products; S3.

2. Correlate the gas phase partition factor obtained in step S1 with the mixed gas volumetric flow rate and average molar mass to establish the effective molar concentration, expressed as: ； in, Effective molar concentration; The volumetric flow rate of the mixed gas. The average molar mass of the mixture is obtained from experimental calculations. Then, the formation rate of each typical product is described in exponential form with temperature as the independent variable, and the expression is: ； in, The formation rate of product p; The apparent activation energy of product p is obtained from the literature; The rate constant factor for product p is determined by technical personnel. Then, the product mass flow rate based on the kinetic model is calculated using the following formula: ； in, The mass flow rate of product p is calculated from the kinetic model; These are measurement correction factors, determined by literature or professionals; The molar mass of product p is determined from the literature; The effective volume of the reactor is obtained from the design specifications; The time unit conversion factor is determined by professionals.

5. The method for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste according to claim 4, characterized in that, The specific implementation method of step S4 includes the following steps: S4.

1. By multiplying and summing the mass flow rates of each product by its lower heating value, and combining this with the combustion efficiency and the lower heating value of the raw materials, the mass flow rates of municipal and industrial solid waste raw materials are calculated in reverse. The calculation formula is: ； in, Mass flow rate of urban and industrial solid waste raw materials; The lower heating value of product p is determined by literature; Combustion efficiency is determined by testing, literature, or professional expertise. The lower calorific value of mixed urban and industrial solid waste raw materials shall be determined by testing or professional personnel. S4.

2. The damage rate caused by mixing, irreversible reaction, and heat transfer is quantified by weighted summation of the differences between the product specific entropy and the reference specific entropy. The calculation formula is as follows: ； in, The destruction rate; The specific entropy of product p is obtained from the literature; The baseline state entropy is determined by literature or professionals. This is a reference temperature, set by a professional. Then, by calculating the product ratio multiplied by the mass flow rate, subtracting the energy destruction rate, and comparing it with the total energy input, the overall energy efficiency of the heat treatment-gasification section, taking into account both energy quantity and quality, is obtained. .

6. The method for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste according to claim 5, characterized in that, The specific implementation method of step S5 includes the following steps: S5.

1. The total cycle energy consumption of carbon capture is calculated by integrating the power of the adsorption stage and the power of the desorption stage over statistical time Δt. ; S5.

2. Set the mass flow rate of product p obtained in step S3. The obtained CO2 mass flow rate To determine the CO2 mass flow rate entering the capture unit, the mass flow rate of successfully captured CO2 is obtained, taking into account the separation efficiency of the capture equipment. The CO2 capture rate is then calculated. ; Then, the total energy consumption per cycle of carbon capture is divided by the mass flow rate of CO2 successfully captured to obtain the energy consumption per unit of CO2 capture. .

7. The method for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste according to claim 6, characterized in that, The expression for the comprehensive objective function constructed in step S6 is as follows: ； in, The value of the comprehensive objective function; ~ These are the efficiency weight, carbon capture weight, environmental impact weight, and model consistency weight, which are determined by literature or professionals. For comprehensive environmental impact indicators; This is a thermodynamic-kinetic consistency penalty term; Then establish and The relationship is ; Change the equivalence ratio ER, pyrolysis temperature T, and gasification pressure vaporization temperature Mixed gas volume flow rate Multiple test conditions were set up, and the optimal heat treatment parameters for urban and industrial solid waste were determined by calculating the comprehensive objective function value Z under different conditions.

8. A system for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste, characterized in that, It includes a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed, implements the steps of the method for optimizing the thermal treatment and carbon capture process of urban and industrial solid waste as described in any one of claims 1-7.

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