Method for calculating nuclear energy supply carbon footprint factor of nuclear power unit

Abstract

The application belongs to the technical field of nuclear energy supply of nuclear power unit, and aims to solve the problem that the traditional carbon footprint factor calculation method does not consider the carbon footprint distribution of two or even multiple products of a single unit, and discloses a kind of calculation method of nuclear energy supply carbon footprint factor of nuclear power unit, which determines the accounting boundary of nuclear energy supply carbon footprint, determines the unit heat supply ratio according to the total flow of main steam and the total flow of steam supply to energy station, determines the carbon footprint distribution proportion of desalted water plant according to the total supply of desalted water plant and the total supply to nuclear power unit, respectively calculates the carbon emission of each emission link of nuclear energy supply, accumulates to obtain the total carbon emission of nuclear energy supply, and calculates the nuclear energy supply carbon footprint factor according to the total carbon emission of nuclear energy supply and the total steam supply of nuclear energy industry. The application can distribute the carbon footprint factor of two or more products of nuclear power plant, and finally determine the carbon footprint factor of nuclear power generation and other products of nuclear energy.

Description

Technical Field

[0001] This application belongs to the field of nuclear power unit nuclear energy steam supply technology, and particularly relates to a method for calculating the carbon footprint factor of nuclear power unit nuclear energy steam supply. Background Technology

[0002] Currently, the carbon footprint factor calculation of nuclear power units only involves the single product of nuclear power generation. With the commissioning of photovoltaic and wind power generation, nuclear power units face the problem of peak shaving. As a result, nuclear power units extract part of the main steam (or turbine interstage steam) to supply steam to chemical industrial parks to improve the thermal efficiency of the units and reduce the impact of peak shaving on the units. At the same time, nuclear power hydrogen production, nuclear power methanol production and other projects are currently being actively planned by nuclear power bases.

[0003] Traditional carbon footprint factor calculation methods do not take into account the carbon footprint allocation methods of two or more products of a single unit, and therefore are not suitable for the current development trend of nuclear power units, thus restricting the carbon footprint accounting of nuclear power units. Summary of the Invention

[0004] The purpose of this application is to provide a method for calculating the carbon footprint factor of nuclear power unit steam supply, which solves the problem that traditional carbon footprint factor calculation methods do not take into account the carbon footprint allocation of two or more products of a single unit.

[0005] To achieve the above objectives, this application provides the following technical solution: This application provides a method for calculating the carbon footprint factor of nuclear power unit steam supply, including the following steps: Step 1: Determine the accounting boundary for the carbon footprint of nuclear power steam supply. The accounting boundary includes the emission links involved in the entire life cycle of nuclear power steam supply of nuclear power units. Step 2: Obtain the total flow rate of the main steam in the secondary loop of the nuclear power unit and the total flow rate of the extracted main steam from the secondary loop of the nuclear power unit supplied to the energy station. Determine the unit's heat supply ratio α based on the total flow rate of the main steam and the total flow rate of the extracted steam supplied to the energy station. Step 3: Obtain the total amount of demineralized water and domestic water supplied to the nuclear power unit's demineralized water plant, as well as the total amount of demineralized water and domestic water supplied to the nuclear power unit. Determine the carbon footprint allocation ratio β of the demineralized water plant based on the total amount supplied to the nuclear power unit and the total amount supplied to the nuclear power unit. Step 4: Calculate the carbon emissions of each emission stage of nuclear steam supply based on the heat supply ratio α and the carbon footprint allocation ratio β of the demineralized water plant. Step 5: Based on the carbon emissions from each emission stage, sum up to obtain the total carbon emissions from nuclear power steam supply; Step 6: Obtain the total steam supply of the nuclear power industry, and calculate the carbon footprint factor of nuclear power supply based on the total carbon emissions of nuclear power supply and the total steam supply of the nuclear power industry.

[0006] As an feasible approach, in step 1, the accounting boundaries include the construction, operation and maintenance, and decommissioning phases of the conventional island, nuclear island, energy station, desalination system, and demineralized water plant, as well as the nuclear fuel cycle phase.

[0007] As an feasible approach, the nuclear fuel cycle phases include the nuclear fuel front end and the nuclear fuel back end. The nuclear fuel front end includes uranium mining and smelting, uranium purification and conversion, uranium enrichment and fuel element manufacturing, while the nuclear fuel back end includes spent fuel reprocessing and waste disposal.

[0008] As an implementable approach, step 1 also includes the discard principle: when the estimated greenhouse gas emissions of a certain emission point are less than or equal to 1% of the estimated greenhouse gas emissions over the life cycle of nuclear power steam supply, the carbon emissions of that emission point are ignored; the total estimated greenhouse gas emissions of all ignored emission points do not exceed 5% of the estimated greenhouse gas emissions over the life cycle of nuclear power steam supply.

[0009] As an feasible approach, in step 2, the formula for calculating the unit's heat supply ratio α is: In the formula, Q ms Q represents the total flow rate of the main steam in the secondary loop of the nuclear power unit. mse The total flow rate of steam extracted from the secondary loop of the nuclear power unit and supplied to the energy station.

[0010] As an feasible approach, in step 3, the formula for calculating the carbon footprint allocation ratio β of the demineralized water plant is: In the formula, Q dwa The total amount of demineralized water and domestic water supplied to the nuclear power unit; Q dw The total amount of demineralized water and domestic water supplied to the demineralized water plant of the nuclear power unit.

[0011] As an feasible approach, step 4 involves various emission stages of nuclear power steam supply, including the nuclear fuel cycle stage, facility decommissioning and dismantling stage, and construction, operation and maintenance stage.

[0012] As an feasible approach, step 4 involves calculating the cycle carbon emissions of nuclear fuel supplied by nuclear power as follows: The carbon emissions from uranium mining and metallurgy, uranium purification and conversion, uranium enrichment, nuclear fuel manufacturing, spent fuel reprocessing, and waste disposal are obtained. The sum of the carbon emissions from each stage is multiplied by the heat supply ratio α to obtain the total carbon emissions of nuclear fuel for nuclear power supply.

[0013] As an feasible approach, the formula for calculating the carbon emissions per cycle of nuclear power-steamed nuclear fuel is as follows: In the formula, Carbon emissions during the steam-powered nuclear fuel cycle; Carbon emissions from uranium mining and treatment; Carbon emissions from uranium purification and conversion; Carbon emissions from uranium purification and conversion; Carbon emissions from uranium enrichment; Nuclear fuel generates carbon emissions; Carbon emissions from spent fuel reprocessing; Carbon emissions from waste disposal.

[0014] As an feasible approach, the method for obtaining carbon emissions from uranium mining and metallurgy, uranium purification and conversion, uranium enrichment, nuclear fuel manufacturing, spent fuel reprocessing, and waste disposal is as follows: The amount of nuclear fuel used during the nuclear lifespan can be estimated based on the annual nuclear fuel consumption, or the carbon emissions of each stage can be calculated based on the amount of process equipment, consumables, and operation and maintenance involved in each stage.

[0015] As an feasible approach, step 4 involves calculating the carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities as follows: The carbon emissions from the decommissioning of the nuclear island, conventional island, demineralized water plant, energy station, and desalination system are obtained. The sum of the carbon emissions from the nuclear island and conventional island decommissioning is multiplied by the heat supply ratio α. The carbon emissions from the demineralized water plant decommissioning are multiplied by the carbon footprint allocation ratio β of the demineralized water plant and then multiplied by the heat supply ratio α. The carbon emissions from the energy station and desalination system decommissioning are directly included. The total carbon emissions during the decommissioning and dismantling phase of the nuclear power steam supply facilities are obtained.

[0016] As an feasible approach, the carbon emissions during the decommissioning and dismantling phase of nuclear steam supply facilities can be calculated using the following formula: In the formula, Carbon emissions from the decommissioning of the nuclear island; Carbon emissions from the decommissioning of conventional islands; Carbon emissions from the decommissioning of the demineralized water plant; Carbon emissions from the decommissioning of energy stations; Carbon emissions from the decommissioning of a desalination system.

[0017] As an feasible approach, step 4 involves calculating the carbon emissions during the construction, operation, and maintenance phases of nuclear power steam supply as follows: The carbon footprint factors of each type of energy and each type of raw material are obtained in each stage of nuclear power steam supply construction, operation and maintenance. The carbon emissions of each stage are calculated by multiplying the consumption of each type of energy and its corresponding carbon footprint factor, and the consumption of each type of raw material and its corresponding carbon footprint factor. The total carbon emissions of the nuclear power steam supply construction, operation and maintenance stage are obtained by summing them up.

[0018] As an feasible approach, the formula for calculating carbon emissions during the construction, operation, and maintenance phases of nuclear power steam supply is as follows: In the formula: E is the set of energy types; M is the set of raw material types; It is classified as a Class E energy carbon footprint factor; This represents the consumption of type e energy (fuel oil, coal, electricity) in stage j. The carbon footprint factor for class m materials; Let be the consumption of type m materials in the j-th stage; j is the j-th stage of the gas supply phase, j∈c={1: civil engineering, 2: installation engineering, 3: equipment manufacturing and system debugging, 4: daily and equipment operation and maintenance, 5: major overhaul and equipment replacement, 6: periodic testing}.

[0019] As an feasible approach, the construction and operation and maintenance processes include civil engineering, installation engineering, equipment manufacturing and system commissioning, daily and equipment operation and maintenance, major overhauls and equipment upgrades, and periodic testing.

[0020] As an feasible approach, in step 6, the formula for calculating the carbon footprint factor of nuclear power steam supply is: In the formula, C ef Carbon footprint factor for nuclear power steam supply; E ff Carbon emissions per nuclear fuel cycle for nuclear power steam supply; E es Carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities; E cs Carbon emissions during the construction, operation, and maintenance phases of nuclear power steam supply; Q ns This refers to the total steam supply during the lifespan of the nuclear power industry.

[0021] As an feasible approach, if the carbon emissions per cycle of nuclear power generation fuel are known, the carbon emissions per cycle of nuclear power steam supply fuel can be calculated using the following formula: In the formula, E ff Carbon emissions per nuclear fuel cycle for nuclear power steam supply; E fe α represents the carbon emissions per cycle of nuclear fuel used in nuclear power generation; α represents the heat supply ratio.

[0022] As an feasible approach, if the carbon emissions during the decommissioning and dismantling phase of a nuclear power generating unit are known, the carbon emissions during the decommissioning and dismantling phase of a nuclear steam supply facility can be calculated using the following formula: In the formula, E es Carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities; E ee α represents the carbon emissions during the decommissioning and dismantling phase of a nuclear power generating unit; α represents the heat supply ratio.

[0023] Compared with existing technologies, the method for calculating the carbon footprint factor of nuclear power unit steam supply provided in this application has the following advantages: This method is applicable to the calculation of the carbon footprint factor of nuclear power unit steam supply, and also applicable to nuclear energy integrated utilization projects such as nuclear hydrogen production and nuclear methanol production. It allocates the carbon footprint factor of two or more products of nuclear power plants, and finally determines the carbon footprint factor of nuclear power generation and other nuclear energy products.

[0024] Furthermore, this method has been successfully applied to "Heqi No. 1," the first nuclear power industrial gas supply project in China. The project's carbon footprint factor has been certified, and the calculated carbon footprint factor for nuclear power steam supply is 0.4606 g CO2e / MJ steam. Data comparison shows that the carbon footprint of nuclear power steam supply is 1 / 600 of that of coal-fired cogeneration steam and 1 / 100 of that of natural gas cogeneration steam. It also demonstrates a more significant low-carbon advantage than chemical steam and is more environmentally friendly than natural gas. This method helps to increase market demand and value for nuclear power steam supply. Attached Figure Description

[0025] To more clearly illustrate the technical solution of this application, the accompanying drawings used in the technical description will be briefly introduced below.

[0026] Figure 1 A flowchart illustrating the method for calculating the carbon footprint factor of nuclear power unit steam supply provided in this application; Figure 2 A schematic diagram of the boundary for calculating the carbon footprint of the nuclear energy industry steam provided in this application. Detailed Implementation

[0027] The following detailed description provides further details on specific implementation methods.

[0028] like Figure 1 As shown, this application provides a method for calculating the carbon footprint factor of nuclear power unit steam supply, including: Step 1: Determine the accounting boundary for the carbon footprint of nuclear power steam supply. The accounting boundary includes the emission links involved in the entire life cycle of nuclear power steam supply of nuclear power units. Step 2: Obtain the total flow rate of the main steam in the secondary loop of the nuclear power unit and the total flow rate of the extracted main steam from the secondary loop of the nuclear power unit supplied to the energy station. Determine the unit's heat supply ratio α based on the total flow rate of the main steam and the total flow rate of the extracted steam supplied to the energy station. Step 3: Obtain the total amount of demineralized water and domestic water supplied to the nuclear power unit's demineralized water plant, as well as the total amount of demineralized water and domestic water supplied to the nuclear power unit. Determine the carbon footprint allocation ratio β of the demineralized water plant based on the total amount supplied to the nuclear power unit and the total amount supplied to the nuclear power unit. Step 4: Calculate the carbon emissions of each emission stage of nuclear steam supply based on the heat supply ratio α and the carbon footprint allocation ratio β of the demineralized water plant. Step 5: Based on the carbon emissions from each emission stage, sum up to obtain the total carbon emissions from nuclear power steam supply; Step 6: Obtain the total steam supply of the nuclear power industry, and calculate the carbon footprint factor of nuclear power supply based on the total carbon emissions of nuclear power supply and the total steam supply of the nuclear power industry.

[0029] The emissions from nuclear power steam supply include the nuclear fuel cycle, facility decommissioning and dismantling, and construction, operation and maintenance.

[0030] Specifically, the method for calculating the carbon emissions per cycle of nuclear fuel for steam supply is as follows: The carbon emissions from uranium mining and metallurgy, uranium purification and conversion, uranium enrichment, nuclear fuel manufacturing, spent fuel reprocessing, and waste disposal are obtained. The sum of the carbon emissions from each stage is multiplied by the heat supply ratio α to obtain the total carbon emissions of nuclear fuel for nuclear power supply.

[0031] Specifically, the method for calculating carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities is as follows: The carbon emissions from the decommissioning of the nuclear island, conventional island, demineralized water plant, energy station, and desalination system are obtained. The sum of the carbon emissions from the nuclear island and conventional island decommissioning is multiplied by the heat supply ratio α. The carbon emissions from the demineralized water plant decommissioning are multiplied by the carbon footprint allocation ratio β of the demineralized water plant and then multiplied by the heat supply ratio α. The carbon emissions from the energy station and desalination system decommissioning are directly included. The total carbon emissions during the decommissioning and dismantling phase of the nuclear power steam supply facilities are obtained.

[0032] Specifically, the method for calculating carbon emissions during the construction, operation, and maintenance phases of nuclear power steam supply is as follows: The carbon footprint factors of each type of energy and each type of raw material are obtained in each stage of nuclear power steam supply construction, operation and maintenance. The carbon emissions of each stage are calculated by multiplying the consumption of each type of energy and its corresponding carbon footprint factor, and the consumption of each type of raw material and its corresponding carbon footprint factor. The total carbon emissions of the nuclear power steam supply construction, operation and maintenance stage are obtained by summing them up.

[0033] This method first clarifies the accounting boundaries and exclusion principles for the carbon footprint of nuclear power steam supply through the entire life cycle process of the nuclear power steam supply unit. Based on these boundaries and principles, it then identifies the carbon emissions of sub-items such as process equipment and operation and maintenance within the accounting boundaries. The unit's heat supply ratio α is determined based on the main steam extraction rate and the main steam supplied to the turbine. The carbon footprint allocation ratio β of the demineralized water supply to the demineralized water plant is determined based on the demineralized water supply ratio. Finally, the carbon emissions from each sub-item of nuclear power steam supply are identified based on the heat supply ratio α and the carbon footprint allocation ratio β of the demineralized water plant equipment. The total carbon emissions from nuclear power steam supply are then derived from the carbon emissions from each sub-item. The nuclear power steam supply carbon footprint factor of the nuclear power unit is obtained by dividing the nuclear power steam supply volume by the total nuclear power steam supply carbon emissions.

[0034] Example This embodiment describes a method for calculating the carbon footprint factor of nuclear power unit steam supply, specifically including the following process: (1) Clarify the accounting boundaries of the carbon footprint of nuclear power supply and define the principles for discarding it, such as... Figure 2 As shown.

[0035] Firstly, by investigating the entire lifecycle of steam in the nuclear energy industry, the emissions within the system boundary were identified as follows: Construction of conventional island, nuclear island, energy station, desalination system, and demineralized water plant; operation and maintenance of nuclear power units; and decommissioning of nuclear power units. The nuclear fuel cycle includes the front end (uranium mining and metallurgy, uranium purification and conversion, uranium enrichment, and fuel element manufacturing) and the back end (spent fuel reprocessing and waste disposal).

[0036] It is specified that if the estimated greenhouse gas emissions of a certain sub-item are less than or equal to 1% of the estimated greenhouse gas emissions over the life cycle of nuclear power steam supply, they can be ignored. However, the total of all ignored greenhouse gas emission estimates shall not exceed 5% of the estimated greenhouse gas emissions over the life cycle of nuclear power steam supply.

[0037] (2) Determine the unit heat supply ratio α based on the main steam extraction rate and the main steam supply to the turbine.

[0038] Obtain the total flow rate of the secondary main steam of the cogeneration nuclear power unit and the total flow rate of the secondary main steam extracted from the nuclear power unit and supplied to the energy station (the total flow rate of the secondary main steam and the total flow rate of the secondary main steam extracted from the nuclear power unit and supplied to the energy station during the service life can be estimated by the annual flow rate). The unit's heat supply ratio α is obtained according to the following formula. In the formula, Q ms Q represents the total flow rate of the main steam in the secondary loop of the nuclear power unit. mse The total flow rate of steam extracted from the secondary loop of the nuclear power unit and supplied to the energy station.

[0039] (3) Determine the carbon footprint allocation ratio β of the demineralized water plant based on the demineralized water supply ratio of the demineralized water plant.

[0040] Obtain the total amount of demineralized water and domestic water supplied by the nuclear power unit's demineralized water plant, and the total amount of demineralized water and domestic water supplied to the cogeneration nuclear power unit (the total amount of demineralized water and domestic water supplied by the nuclear power unit's demineralized water plant and the total amount of demineralized water and domestic water supplied to the cogeneration nuclear power unit can be estimated through annual flow rates). The carbon footprint allocation ratio β of the demineralized water plant is obtained according to the following formula: In the formula, Q dwa Q is the total amount of demineralized water and domestic water supplied to the nuclear power unit. dw The total amount of demineralized water and domestic water supplied to the demineralized water plant of the nuclear power unit.

[0041] (4) Calculate the carbon emissions of nuclear power steam supply nuclear fuel cycle.

[0042] The carbon emissions from uranium mining and processing, uranium purification and conversion, uranium enrichment, nuclear fuel manufacturing, spent fuel reprocessing, and waste disposal can be obtained (the annual nuclear fuel consumption during the nuclear fuel's lifespan can be estimated based on the annual nuclear fuel consumption), or the carbon emissions from each stage can be calculated based on the process equipment, consumables, and maintenance involved. The cycle carbon emissions of nuclear power steam supply nuclear fuel can be obtained using the following formula. In the formula, Carbon emissions during the steam-powered nuclear fuel cycle; Carbon emissions from uranium mining and treatment; Carbon emissions from uranium purification and conversion; Carbon emissions from uranium purification and conversion; Uranium enrichment carbon emissions; Nuclear fuel generates carbon emissions; Carbon emissions from spent fuel reprocessing; Carbon emissions from waste disposal.

[0043] If the carbon emissions per cycle of nuclear power generation fuel are known, the carbon emissions per cycle of nuclear power steam supply fuel can be estimated using the following formula: In the formula, E ff E represents the carbon emissions during the nuclear fuel cycle for nuclear power steam supply. fe α represents the carbon emissions per cycle of nuclear fuel used in nuclear power generation, and α represents the heat supply ratio.

[0044] (5) Calculate the carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities.

[0045] The carbon emissions from the decommissioning of the nuclear island, conventional island, demineralized water plant, power station, and desalination system can be obtained, or calculated based on the process equipment and consumables used in each stage. The cycle carbon emissions of nuclear power steam supply and nuclear fuel can be derived using the following formula. In the formula, Carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities; Carbon emissions from the decommissioning of the nuclear island; Carbon emissions from the decommissioning of conventional islands; Carbon emissions from the decommissioning of the demineralized water plant; Carbon emissions from the decommissioning of energy stations; Carbon emissions from the decommissioning of ocean desalination systems.

[0046] If the carbon emissions during the decommissioning and dismantling phase of a nuclear power generator unit are known, the carbon emissions during the decommissioning and dismantling phase of a nuclear steam supply facility can be estimated using the following formula: In the formula, E es Carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities; E ee α represents the carbon emissions during the decommissioning and dismantling phase of a nuclear power generating unit; α represents the heat supply ratio.

[0047] (6) Calculate the carbon emissions during the construction, operation and maintenance phases of nuclear power steam supply facilities.

[0048] Obtain the carbon emissions from the excavation and subsurface excavation of the plant area, the carbon emissions from the construction and equipment manufacturing of the nuclear island project, the carbon emissions from the construction and equipment manufacturing of the conventional island project, the carbon emissions from the construction and equipment manufacturing of the demineralized water plant project, the carbon emissions from the construction and equipment manufacturing of the energy station project, the carbon emissions from the construction and equipment manufacturing of the seawater desalination system project, and the carbon emissions from the excavation and subsurface excavation of the energy station and seawater desalination system. Calculate the carbon emissions during the construction, operation, and maintenance phases of the nuclear power steam supply facilities using the following formula. In the formula: E is the set of energy types; M is the set of raw material types; It is classified as a Class E energy carbon footprint factor; This represents the consumption of type e energy (fuel oil, coal, electricity) in stage j. The carbon footprint factor for class m materials; Let be the consumption of type m materials in the j-th stage; j is the j-th stage of the gas supply phase, j∈c={1: civil engineering, 2: installation engineering, 3: equipment manufacturing and system debugging, 4: daily and equipment operation and maintenance, 5: major overhaul and equipment replacement, 6: periodic testing}.

[0049] (7) Calculate the carbon footprint factor of nuclear power steam supply.

[0050] Obtain the total steam supply of the nuclear power industry (the total steam supply of the nuclear power industry during its lifespan can be calculated based on the annual total steam supply), and calculate the carbon footprint factor of nuclear power steam supply using the following formula. In the formula, C ef Carbon footprint factor for nuclear power steam supply; E ff Carbon emissions per nuclear fuel cycle for nuclear power steam supply; E es Carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities; E cs Carbon emissions during the construction, operation, and maintenance phases of nuclear power steam supply; Q ns This refers to the total steam supply during the lifespan of the nuclear power industry.

[0051] The above description is only a specific embodiment of this application, but the protection scope of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the protection scope of this application.

Claims

1. A method for calculating the carbon footprint factor of nuclear power unit steam supply, characterized in that, include: Step 1: Determine the accounting boundary for the carbon footprint of nuclear power steam supply. The accounting boundary includes the emission links involved in the entire life cycle of nuclear power steam supply of nuclear power units. Step 2: Obtain the total flow rate of the main steam in the secondary loop of the nuclear power unit and the total flow rate of the extracted main steam from the secondary loop of the nuclear power unit supplied to the energy station. Determine the unit's heat supply ratio based on the total flow rate of the main steam and the total flow rate of the extracted steam supplied to the energy station. Step 3: Obtain the total amount of demineralized water and domestic water supplied by the nuclear power unit's demineralized water plant and the total amount of demineralized water and domestic water supplied to the nuclear power unit. Determine the carbon footprint allocation ratio of the demineralized water plant based on the total amount supplied by the demineralized water plant and the total amount supplied to the nuclear power unit. Step 4: Calculate the carbon emissions of each emission stage of nuclear steam supply based on the heat supply ratio and the carbon footprint allocation ratio of the demineralized water plant. Step 5: Based on the carbon emissions from each emission stage, sum up to obtain the total carbon emissions from nuclear power steam supply; Step 6: Obtain the total steam supply of the nuclear power industry, and calculate the carbon footprint factor of nuclear power supply based on the total carbon emissions of nuclear power supply and the total steam supply of the nuclear power industry.

2. The method for calculating the carbon footprint factor of nuclear power unit steam supply according to claim 1, characterized in that, The accounting boundaries include the construction, operation and maintenance, decommissioning and dismantling, and nuclear fuel cycle phases of the conventional island, nuclear island, energy station, desalination system and demineralized water plant.

3. The method for calculating the carbon footprint factor of nuclear power unit steam supply according to claim 1, characterized in that, The formula for calculating the unit's heat supply ratio α is: The formula for calculating the carbon footprint allocation ratio β of the demineralized water plant is: In the formula, Q ms Q represents the total flow rate of the main steam in the secondary loop of the nuclear power unit. mse Q represents the total flow rate of the main steam extracted from the secondary loop of the nuclear power unit to the energy station; dwa Q is the total amount of demineralized water and domestic water supplied to the nuclear power unit. dw The total amount of demineralized water and domestic water supplied to the demineralized water plant of the nuclear power unit.

4. The method for calculating the carbon footprint factor of nuclear power unit steam supply according to claim 1, characterized in that, The emissions from nuclear power steam supply include the nuclear fuel cycle, facility decommissioning and dismantling, and construction, operation and maintenance.

5. The method for calculating the carbon footprint factor of nuclear power unit steam supply according to claim 4, characterized in that, The formula for calculating the carbon emissions per cycle of nuclear power steam supply nuclear fuel is: In the formula, Carbon emissions from uranium mining and treatment; Carbon emissions from uranium purification and conversion; Carbon emissions from uranium purification and conversion; Uranium enrichment carbon emissions; Nuclear fuel generates carbon emissions; Carbon emissions from spent fuel reprocessing; Carbon emissions from waste disposal.

6. The method for calculating the carbon footprint factor of nuclear power unit steam supply according to claim 5, characterized in that, If the carbon emissions per cycle of nuclear power generation fuel are known, the carbon emissions per cycle of nuclear power steam supply fuel can be calculated using the following formula: In the formula, E fe α represents the carbon emissions per cycle of nuclear fuel used in nuclear power generation; α represents the heat supply ratio.

7. The method for calculating the carbon footprint factor of nuclear power unit steam supply according to claim 4, characterized in that, The formula for calculating carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities is: In the formula, Carbon emissions from the decommissioning of the nuclear island; Carbon emissions from the decommissioning of conventional islands; Carbon emissions from the decommissioning of the demineralized water plant; Carbon emissions from the decommissioning of energy stations; Carbon emissions from the decommissioning of a desalination system.

8. The method for calculating the carbon footprint factor of nuclear power unit steam supply according to claim 7, characterized in that, If the carbon emissions during the decommissioning and dismantling phase of a nuclear power generator unit are known, the carbon emissions during the decommissioning and dismantling phase of a nuclear steam supply facility are calculated using the following formula: In the formula, E ee α represents the carbon emissions during the decommissioning and dismantling phase of a nuclear power generating unit; α represents the heat supply ratio.

9. The method for calculating the carbon footprint factor of nuclear power unit steam supply according to claim 4, characterized in that, The formula for calculating carbon emissions during the construction, operation, and maintenance phases of nuclear power steam supply is: In the formula: M is the set of raw material types; It is classified as a Class E energy carbon footprint factor; This represents the energy consumption of type e in stage j. The carbon footprint factor for class m materials; Let m be the consumption of material type m in the j-th stage.

10. The method for calculating the carbon footprint factor of nuclear power unit steam supply according to claim 1, characterized in that, The formula for calculating the carbon footprint factor of nuclear power steam supply is: In the formula, E ff Carbon emissions per nuclear fuel cycle for nuclear power steam supply; E es Carbon emissions during the decommissioning and dismantling phase of nuclear power steam supply facilities; E cs Carbon emissions during the construction, operation, and maintenance phases of nuclear power steam supply; Q ns This refers to the total steam supply during the lifespan of the nuclear power industry.

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