A method and system for calculating carbon emissions from contaminated site remediation based on multi-source data fusion

Abstract

This invention discloses a method and system for calculating carbon emissions from contaminated site remediation based on multi-source data fusion, belonging to the field of environmental remediation and carbon management technology. The method includes: determining the system boundary for calculating carbon emissions from contaminated site remediation; identifying all potential carbon sources and potential carbon sinks within the system boundary; collecting activity data of potential carbon sources and calculating multi-dimensional carbon source emissions; when remediation technologies include phytoremediation, using the biomass method to calculate the technical carbon sink; analyzing the physicochemical properties of the site soil before and after remediation to calculate the soil carbon pool disturbance; and calculating the net carbon emissions from contaminated site remediation by coupling analysis of carbon sources and carbon sinks. This invention integrates three major carbon flows—"material and energy carbon sources," "technological carbon sinks," and "soil carbon pool disturbance"—into a unified calculation framework. By fusing multi-source data, it achieves accurate quantification of the net carbon effect of remediation activities, providing technical support for the green and low-carbon transformation of the contaminated site remediation industry.

Description

Technical Field

[0001] This invention relates to the field of environmental remediation and carbon management technology, and in particular to a method and system for calculating carbon emissions from contaminated site remediation through multi-source data fusion. Background Technology

[0002] Traditional contaminated site remediation strategies primarily focus on pollutant removal efficiency, remediation cycle, and cost, often neglecting the environmental footprint of the remediation activities themselves, particularly greenhouse gas emissions generated during energy consumption, material production, and transportation. Currently, some research is addressing the carbon footprint of site remediation, mainly employing Life Cycle Assessment (LCA) methods. For example, some studies have established inventories to calculate the carbon emissions corresponding to material and energy consumption during the engineering implementation phase of technologies such as solidification / stabilization and thermal desorption.

[0003] However, existing technologies and methods have significant limitations. First, the measurement boundaries are incomplete. Most studies focus only on the "carbon sources" in the remediation process, namely material production and energy consumption, while systematically ignoring the "carbon sink" effect that the remediation technology itself may generate. For example, phytoremediation technology can directly fix atmospheric CO2 through photosynthesis, forming a significant carbon sink. If this is not taken into account, its net carbon emissions will be overestimated. Second, there is a lack of quantitative assessment of the disturbance effect on the soil carbon pool. Soil is the largest carbon pool in terrestrial ecosystems. Remediation activities, such as excavation, soil turning, chemical application, and thermal treatment, can drastically change the physical structure, chemical properties, and microbial community of the soil, thereby affecting the decomposition and fixation of soil organic carbon and potentially causing the soil carbon pool to become an additional "carbon source" or "carbon sink." Existing methods generally fail to incorporate this dynamic change into the measurement system, resulting in a significant discrepancy between the measured results and the actual climate impact of remediation activities.

[0004] In summary, current methods for measuring carbon emissions from contaminated site remediation are one-sided and cannot fully and accurately reflect the net impact of remediation activities on the carbon cycle. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for calculating carbon emissions from contaminated site remediation based on multi-source data fusion. This method couples three core carbon flow pathways: "material energy carbon source", "technology-based carbon sink", and "soil carbon pool disturbance". This enables a scientific assessment of the net carbon effect of contaminated site remediation, thereby providing key technical support for selecting truly green and low-carbon remediation technologies, optimizing remediation engineering design, and achieving green and low-carbon development in the industry.

[0006] To achieve the above objectives, this invention provides a method for calculating carbon emissions from contaminated site remediation based on multi-source data fusion, comprising the following steps: S1. Determine the system boundary for carbon emission measurement of contaminated site remediation. The system boundary covers the entire life cycle of the remediation project from material production to final disposal, and incorporates the carbon sink effect of remediation technology and the soil carbon pool effect as measurement elements. S2. Identify all potential carbon sources and potential carbon sinks within the system boundary. Potential carbon sources include energy consumption and material consumption, while potential carbon sinks include the carbon sink effect brought about by remediation technologies and changes in the soil carbon pool. S3. Collect data on potential carbon source activities, and using the emission factor database, calculate multi-source carbon emissions using the emission factor method, denoted as C. emission ; S4. When the remediation technology includes phytoremediation, the amount of carbon fixed by the plant during its growth cycle is calculated using the biomass method based on measured plant biomass data, and is denoted as C. sink-tech ; S5. By conducting stratified sampling and laboratory analysis of the site before and after remediation, measured data including soil organic carbon content, soil bulk density, and gravel content were obtained. The direct monitoring method was used to calculate the change in soil carbon pool storage caused by the remediation activities, denoted as S5. S6. Based on the calculation results of potential carbon sources and potential carbon sinks from multiple dimensions, the net carbon emissions from contaminated site remediation are obtained through coupling analysis, denoted as... .

[0007] Preferably, in S1, the system boundary includes the material production and transportation stage, the engineering implementation stage, and the post-remediation waste and equipment disposal stage in the time dimension; the spatial boundary is centered on the physical extent of the contaminated site and covers the scope of remediation activities.

[0008] Preferably, in S2, energy consumption includes the direct and indirect use of various types of energy during the repair process, including the operation of on-site and off-site transportation equipment, repair equipment and auxiliary equipment; material consumption includes materials and agents used during the repair process, including cement and steel used for on-site facility construction, repair agents and consumables, exhaust gas / wastewater treatment adsorbents and waste disposal-related materials.

[0009] Preferably, in S2, the carbon sink effect brought about by the remediation technology specifically refers to the absorption of atmospheric carbon dioxide by vegetation through photosynthesis and its fixation in biomass during phytoremediation; the change in soil carbon pool refers to the net change in soil organic carbon storage caused by the change in soil physicochemical properties due to the implementation of remediation technology, which in turn affects the input, decomposition and transformation process of soil organic carbon.

[0010] Preferably, in S3, the activity data for energy consumption and material consumption first adopt the original data, including on-site records and procurement records. When the original data is missing, the statistical data of similar projects and industry report data are used as a reference. The emission factors are used in the following order: China Greenhouse Gas Emission Accounting and Reporting Guidelines, emission factors issued by local ecological and environmental departments, international authoritative databases, and publicly published academic reports.

[0011] Preferably, in S3, the carbon source emission C emission The calculation formula is: ; in, For the activity data of the i-th material, This refers to the carbon emission factor throughout the entire life cycle of the material. For the activity data of the j-th energy source, This represents the carbon emission factor corresponding to this energy source.

[0012] Preferably, in S4, the carbon sequestration is calculated using the biomass method. sink-tech The calculation formula is: C sink-tech ; Where A is the planting area in m. 2 B represents the plant biomass per unit area (kg / m²). 2 ; The carbon content of herbaceous plants is represented by data from both published data and measured data.

[0013] Preferably, in S5, the site is divided into several plot units for grid-based sampling based on the degree of site remediation disturbance and soil type. At least three layers of soil samples are collected at the same sampling point before and after remediation. The actual sampling depth is adjusted according to the vertical distribution of pollutants and the depth of remediation disturbance. At least two parallel samples are collected at each layer depth for homogenization analysis.

[0014] Preferably, in S5, the change in site carbon pool storage is calculated by measuring the soil organic carbon content before and after remediation. The calculation formula is: ; Where i is the plot sampling unit number, SOC post,i SOC pre,i Soil organic carbon content (g / kg) of sampling unit i in plot i before and after remediation were calculated, and the average of the two samples was taken. i The soil bulk density of sampling unit i is kg / m³ 3 D i Let A be the soil layer depth m for sampling unit i. iLet m be the area of ​​sampling unit i. 2 G i The volume ratio of gravel content in sampling unit i is given, and its diameter is >2mm.

[0015] This invention also provides a multi-source data fusion system for calculating carbon emissions from contaminated site remediation, including a data acquisition module, a factor database module, a multi-source carbon source-carbon sink calculation module, a carbon emission reduction analysis module, and a result analysis module. The data acquisition module is used to collect activity data on material consumption, energy consumption, plant growth, and soil parameters throughout the entire life cycle of a contaminated site remediation project, through interfaces and manual input. The factor database module is used to hierarchically store emission factors of materials and energy and plant carbon sink parameters corresponding to the activity data; The multi-source carbon source-carbon sink calculation module is connected to the data acquisition module and the factor database module, and is used to calculate carbon source emissions C. emission Carbon sequestration of technology (C) sink-tech and changes in soil carbon storage By performing a coupled analysis of the three factors, the net carbon emissions C were determined. net ; The carbon emission reduction analysis module is used to identify key carbon emission links in the remediation project based on the contribution analysis of each carbon source, and to evaluate the potential effects of different emission reduction measures in conjunction with a pre-set emission reduction scenario library. The results analysis module is used to visualize the net carbon emissions, the distribution of carbon source and sink contributions, key carbon emission links, and the assessment results of emission reduction measures, and automatically generate a carbon footprint analysis report.

[0016] Therefore, this invention adopts the above-mentioned multi-source data fusion carbon emission calculation method and system for contaminated site remediation. By incorporating the three major carbon flows of "material energy carbon source", "technology carbon sink" and "soil carbon pool disturbance" into a unified calculation framework and integrating multi-source data, it achieves accurate quantification of the net carbon effect of remediation activities. This provides key technical support for the green and low-carbon transformation of the contaminated site remediation industry and helps to promote the transformation of contaminated site remediation from simple pollutant removal to comprehensive environmental governance that takes into account climate benefits.

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0018] Figure 1 This is a flowchart of the carbon emission calculation method for contaminated soil remediation using plant extraction technology provided in this embodiment of the invention; Figure 2This is a flowchart of the carbon emission calculation method for contaminated soil remediation using thermal desorption technology provided in this embodiment of the invention; Figure 3 This is a schematic diagram of the module composition of the carbon emission calculation system for contaminated site remediation provided in an embodiment of the present invention. Detailed Implementation

[0019] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0021] 1. System Boundaries and Measurement Scope First, clearly define the system boundaries for carbon emission measurement of contaminated site remediation to ensure the comprehensiveness and consistency of the measurement.

[0022] In terms of time dimension, it covers the entire life cycle of the restoration project, from upstream material production to downstream waste disposal, namely "preliminary preparation stage (the process of producing, manufacturing and transporting the equipment and materials required for restoration to the construction site) → project implementation stage (covering all on-site activities such as site clearing, site energy and material consumption) → off-site disposal stage (equipment dismantling, cleaning and removal from the site, as well as the transportation and final disposal of construction waste, waste consumables and other items generated during the restoration process)", avoiding the incomplete cycle caused by only calculating the restoration project implementation stage.

[0023] In terms of spatial dimensions, it covers all physical areas related to remediation activities, including but not limited to the core area for contaminated site remediation (contaminated soil excavation / in-situ remediation area), material storage and pretreatment area (remediation agent storage area), and energy supply-related area (temporary power plant, power grid coverage area), ensuring that all carbon flows directly related to remediation activities are included.

[0024] Furthermore, the carbon sink effect of remediation technology and the soil carbon pool effect are included as measurement factors within this boundary, achieving comprehensive coverage of carbon flows beyond traditional carbon sources. The year prior to the start of the remediation project is used as the baseline period for the soil carbon pool, to compare changes in the soil carbon pool after remediation and to eliminate the interference of natural climate fluctuations on soil carbon storage.

[0025] 2. Identification of carbon sources and carbon sinks Within the defined system boundaries, identify all potential carbon sources and sinks.

[0026] Potential carbon sources (C emission It mainly includes two categories: Energy consumption: The direct or indirect use of various energy sources during the restoration process, including but not limited to diesel, gasoline, electricity, natural gas, etc. consumed by vehicles transporting the restoration equipment and auxiliary equipment inside and outside the site.

[0027] Material consumption: Various materials and agents are used in the repair process, including but not limited to cement and steel used for on-site facility construction, repair agents and consumables, adsorbents for exhaust gas / wastewater treatment, and materials related to waste disposal.

[0028] Potential carbon sinks (C sink It mainly includes two categories: Carbon sequestration remediation technology (C sink-tech ): This specifically refers to the process in phytoremediation where vegetation absorbs atmospheric carbon dioxide through photosynthesis and fixes it in biomass (including above-ground and below-ground parts). For technologies that do not involve phytoremediation, this carbon sequestration is zero.

[0029] Soil carbon pool changes ( This refers to the net change in soil organic carbon storage caused by changes in soil physicochemical properties resulting from the implementation of remediation technologies (such as soil tillage, chemical application, and temperature changes), which in turn affect the input, decomposition, and transformation processes of soil organic carbon. If remediation activities lead to an increase in soil organic carbon storage, this item is negative (carbon sink); if they lead to a decrease in storage, it is positive (carbon source).

[0030] 3. Multi-source data fusion and measurement methods By employing a multi-source data fusion strategy, combining on-site measured data, engineering statistical data, and authoritative database data, accurate calculations of the three major carbon flows mentioned above can be achieved.

[0031] Carbon source emissions (C emission ) calculation The lifecycle inventory approach is employed to comprehensively assess all materials and energy consumed during the remediation process. Combined with an emissions factor database, the total carbon emissions over the entire lifecycle are calculated. Specifically, primary data such as on-site records and procurement records are prioritized as activity-level data. When primary data is lacking, statistical data from similar projects or industry reports are referenced. Emission factors are used in the following order: Chinese Greenhouse Gas Emissions Accounting and Reporting Guidelines, emissions factors published by local environmental protection departments, authoritative international databases (such as the IPCC Emissions Factor Database (EFDB), and publicly published academic reports), to ensure the accuracy and credibility of the calculation results.

[0032] Material carbon emissions (C emission-m Carbon emissions include those from the production, use, and disposal of remediation agents (such as heavy metal stabilizers and organic matter degrading agents), filler materials (such as cleaning soil), remediation consumables (such as filter membranes), and construction materials (such as cement).

[0033] Energy carbon emissions (C emission-e Carbon emissions include those from the consumption of electricity (such as equipment power supply), fuel oil (such as excavators and transport vehicles), natural gas (such as thermal degassing with additional heat), and water resources.

[0034] Total carbon emissions (C emission The total carbon emissions from the remediation process are obtained by adding the carbon emissions from the above materials and energy sources; this is a positive value (carbon source). The calculation formula is as follows: ; Among them, AD m,i For the activity data of the i-th material, EF m,i This refers to the carbon emission factor over the entire life cycle of the material; AD e,j For the activity data of the j-th energy source, EF e,j This represents the carbon emission factor corresponding to this energy source.

[0035] Technology carbon sequestration (C sink-tech ) calculation When phytoremediation is included in the remediation technology, this method is based on measured plant biomass data and uses the biomass method to calculate the amount of carbon fixed by the plant during its growth cycle. Specifically, at the end of the remediation period, the total planted area and average biomass per unit area are obtained through field sampling and measurement. These data, along with the plant carbon content, are then substituted into the formula for calculation (the default value in this method is 0.3713, referencing "Carbon Content and Characteristics of Terrestrial Higher Plants," 2004). If measured data is used, the data source should be indicated. The calculation formula is as follows: C sink-tech ; Where A is the planted area (m²) 2B represents the plant biomass per unit area (kg / m²). 2 ); C f Carbon content of herbaceous plants.

[0036] For technologies that do not involve phytoremediation, this carbon sequestration is zero.

[0037] Changes in soil carbon pool ( ) calculation By comparing soil carbon storage before and after remediation, the impact of remediation activities on the soil carbon pool is quantified. Specifically, stratified soil sampling was conducted before and after remediation, and key parameters such as soil organic carbon content, soil bulk density, and gravel content were obtained through laboratory analysis. The sampling plan required dividing the site into several plots based on the degree of remediation disturbance and soil type, and conducting gridded sampling. For each plot, at least three layers of soil samples (e.g., 0-20cm, 20-50cm, 50-100cm, with the actual sampling depth adjusted according to the vertical distribution of pollutants and the depth of remediation disturbance) were collected from the same sampling point before and after remediation. At least two parallel samples were collected from each layer for homogenization and analysis. The calculation formula is as follows: ; Where i is the plot sampling unit number, SOC post,i SOC pre,i Soil organic carbon content (g / kg) of sampling unit i in plot before and after remediation (mean value of 2 samples, %), BD i The soil bulk density (kg / m³) of sampling unit i 3 ), D i Let A be the soil layer depth (m) of the sampling unit for plot i. i The area (m) of sampling unit i 2 ), G i The volume ratio of gravel content in sampling unit i (diameter > 2 mm). If A negative value indicates a decrease in soil carbon storage, meaning that remediation activities have led to an increase in carbon sources. If... A positive value indicates a decrease in soil carbon storage, meaning that remediation activities promote soil carbon sequestration.

[0038] Net carbon emissions (C net Coupled computation Substituting the three components calculated above into the core coupling formula of this invention, the net carbon emissions of the remediation activity are calculated. The calculation formula is as follows: .in: If C net A value >0 indicates that the overall remediation activity is a net carbon source; the higher the value, the higher the carbon emission intensity.

[0039] If Cnet A value less than 0 indicates that the overall remediation activity is a net carbon sink; the smaller the value (the larger the absolute value), the more significant the carbon sink benefit.

[0040] Example 1 Taking a remediation project of farmland contaminated by a lead-zinc mine using phytoremediation technology as an example, the application process of this method is described, as follows: Figure 1 As shown.

[0041] S1. Determine the system boundary This boundary covers the entire lifecycle in terms of time, from the "construction preparation phase" (production and transportation of equipment and materials) to the "remediation project implementation phase" (on-site excavation, pesticide application, and plant planting and maintenance), and then to the "post-remediation disposal phase" (equipment removal and waste disposal). Spatially, it includes the remediation core area and material storage area. Furthermore, the carbon sequestration effect of phytoremediation and changes in the soil carbon pool are also incorporated into this boundary.

[0042] In this embodiment, the area of ​​the moderately polluted zone is 258,667 m². 2 The thickness of the repaired soil layer was 15 cm, and the total volume of earthwork repaired was 38,800 m³. 3 The soil pH range in this area is 4.42–8.79, with an average organic matter content of 23.55 g / kg. The main pollutant is cadmium, with a total concentration of 2.67 ± 0.76 mg / kg. By planting hyperaccumulating plants and implementing agronomical regulation, soil heavy metal pollution can be controlled and remediated to reduce ecological risks, ensuring a significant reduction in both total and available cadmium levels in the remediated soil. This case study uses the hyperaccumulating plant *Sedum aizoon*, with a planting cycle of two years. Based on the local climate and soil conditions, *Sedum aizoon* is planted annually in a single season, transplanted from April to May (early rainy season) and harvested from September to October (late rainy season). The planted plants are grown on raised beds at a density of 50,000 plants per acre. During the planting period, field management is carried out according to actual conditions, including weeding, pest control, and fertilization. The average yields of *Sedum aizoon* in the first and second seasons were 2.01 t / ha and 0.98 t / ha, respectively, with average cadmium concentrations in the aboveground parts of 168 mg / kg and 171 mg / kg, respectively. After maturity, the *Sedum aizoon* was harvested and transported to a disposal site for incineration. Safe incineration was achieved at 850℃ by adding calcium oxide and activated carbon to absorb harmful substances in the flue gas. Heavy metals in the fly ash and bottom ash after incineration could be utilized as resources. After two seasons of phytoremediation, the total cadmium content in the soil decreased by approximately 40%.

[0043] The process of phytoremediation of heavy metal pollution in agricultural land is divided into five stages: 1) Plant selection and cultivation stage: Based on preliminary site investigation reports, risk assessment reports, and other data, the type of soil pollution is identified, and suitable hyperaccumulating plant varieties are selected; through small-scale experiments, planting technology schemes are clarified and large-scale plant cultivation is carried out; 2) On-site remediation stage: To ensure the plant growth environment, rotary tillage and drainage ditch construction are carried out on the agricultural land to meet the water needs during the dry season and flood drainage during the rainy season; base fertilizer is applied to the agricultural land to ensure suitable soil fertility; pesticides are sprayed on the agricultural land to prevent the impact of pests; agricultural film is used to cover the agricultural land to ensure soil temperature and suppress weeds; 3) Plant growth stage: Suitable plant branches are selected for cutting propagation; during the plant growth period, field management work such as weeding, pest control, and topdressing is carried out according to the actual situation; 4) Plant harmless disposal stage: When the plant biomass reaches its maximum, it is removed, transported, and centrally incinerated; 5) Effect evaluation stage: The effect of agricultural land soil remediation is evaluated, and the remediation project ends after acceptance.

[0044] S2. Identifying Carbon Sources and Sequestrations Within the defined system boundaries, all potential carbon sources were identified. These sources primarily fall into two categories: energy consumption, such as diesel fuel consumed by remediation equipment and transport vehicles, and electricity consumed by on-site auxiliary engineering equipment; and material consumption, such as pesticides, fertilizers, and incineration additives consumed during the planting, maintenance, harvesting, and disposal of hyperaccumulating plants. Potential carbon sinks include: first, remediation technology carbon sinks, i.e., carbon dioxide fixed by plants through photosynthesis; and second, changes in the soil carbon pool, i.e., the net impact of remediation activities on soil organic carbon storage.

[0045] S3. Collect carbon source activity data and calculate carbon emissions. The data acquisition and calculation phase then begins. Activity level data for all carbon sources identified in S2 are collected through on-site records and engineering ledgers, including total diesel consumption, total electricity consumption, and total reagent dosage. Subsequently, from the emission factor database, the most suitable carbon emission factor is matched for each activity data point according to priority (official database > international database > literature). Finally, based on the emission factor method formula, all activity data are multiplied by their corresponding emission factors and summed to calculate a quantitative total carbon emission (C). emission ).

[0046] The carbon sources in this embodiment are summarized in Table 1 below: Table 1 Carbon Source Inventory

[0047] S4. Calculate the carbon sequestration effect of phytoremediation technology. For the phytoremediation step included in this embodiment, the biomass method was used for quantification. At the end of the remediation period, the total planted area and average biomass per unit area were obtained through field sampling and measurement. These data, along with the preset plant carbon content, were substituted into the biomass method formula to calculate a quantitative carbon sink (C1) of the remediation technology itself. sink-tech ).

[0048] In this embodiment, the carbon sequestration of plants is calculated as follows: the planted area is 258,667 m². 2 The plant biomass per unit area is 0.3 (kg / m²). 2 The carbon content of herbaceous plants is 0.3713 (refer to "Carbon Content and Characteristics of Terrestrial Higher Plants", 2007). The carbon sink generated by plant growth is calculated to be 105.65t.

[0049] S5. Calculate the change in soil carbon pool. To assess the impact of remediation on the soil carbon pool, stratified soil samples were collected before and after remediation. Laboratory analysis yielded key parameters such as soil organic carbon content, soil bulk density, and gravel content at each sampling point before and after remediation. These monitoring data were then substituted into the formula for calculating soil carbon pool change to calculate the soil carbon pool disturbance flux (…). A positive value indicates a loss of soil carbon pool (carbon source), while a negative value indicates an increase in soil carbon pool (carbon sink).

[0050] In this embodiment, the sources of soil carbon pool changes include: ① Vegetation input: As a perennial herb, Sedum sarmentosum produces a large amount of root residue during its growth period (even if the above-ground parts are harvested and removed, the roots remain in the soil), and root exudates (such as organic acids and polysaccharides) also replenish the soil with organic carbon sources; ② Nutrient supplementation: Applying compound fertilizer before planting not only provides nutrients for plants, but also promotes soil microbial activity through unabsorbed nutrients, indirectly promoting the transformation and accumulation of organic carbon; ③ Erosion control: Ridging and mulching, and the construction of ditches reduce soil erosion during the rainy season and wind erosion during the dry season, reducing the risk of organic carbon loss.

[0051] Based on the planting and maintenance management measures implemented in this case, the organic matter content in the top 0-15 cm soil layer increased by 20%. The initial average organic matter content was 23.55 g / kg, and after remediation, the organic matter content increased by approximately 7.065 g / kg. The calculated increase in soil organic matter content is: 4.71 g / kg × 1.2 t / m³. 3 (1m) 3 The soil mass is taken as 1.2t) × 38800 m3 = 219.30t, which is converted to organic carbon content as: 219.30t × 0.58 (classic conversion factor between organic matter and organic carbon) = 127.19t.

[0052] S6. Calculate net carbon emissions The three quantitative results C obtained from S3, S4, and S5 respectively emission C sink-tech and Substitute into the coupling formula Ultimately, a net carbon emission C that reflects the true environmental impact is calculated. net In this embodiment, the net carbon emissions generated during the entire remediation process are: 361.71t - 105.65t - 127.19t = 128.87t.

[0053] Example 2 A method for calculating carbon emissions from contaminated soil remediation that incorporates thermal desorption technology, the process of which is as follows: Figure 2 As shown, it includes the following steps: S1. Determine the system boundary The time boundary covers the entire process from the manufacturing and transportation of thermal desorption equipment, site preparation, excavation and transportation of contaminated soil, thermal desorption treatment, backfilling of treated soil, and waste gas / wastewater treatment. The spatial boundary includes the contaminated site, the area where the thermal desorption equipment is located, the transportation route, and the power grid coverage area of ​​the power source. The calculation elements include material energy carbon sources and soil carbon pool disturbances. Since thermal desorption technology does not have carbon sequestration mechanisms such as photosynthesis, it does not involve technology carbon sinks.

[0054] This example selects a petroleum hydrocarbon pollution waste site with a pollution area of ​​approximately 600m². 2 The contamination depth is 1.5-6.0m, and the total amount of contaminated soil is approximately 2700m³. 3 Soil bulk density 1.8 g / cm³ 3 The initial TPH concentration is 800-5200 mg / kg.

[0055] Remediation technology: In-situ thermal desorption by electric heating, which raises the soil temperature to 120-180℃ by inserting heating electrodes into the soil. The total construction period is 90 days, including 25 days for the heating and warming stage, 45 days for the constant temperature stage, and 20 days for the cooling and finishing stage.

[0056] S2. Identifying Carbon Sources and Sequestrations Carbon source (C emission This mainly includes: energy consumption, such as natural gas and electricity consumed in the operation of thermal desorption equipment, diesel fuel consumed in transportation, and electricity consumed by the exhaust gas treatment system, wastewater treatment facilities, and on-site lighting; and material consumption, such as consumables used in the operation of thermal desorption equipment and activated carbon that may be used in the exhaust gas purification process. Regarding carbon sequestration, since thermal desorption does not involve phytoremediation, the technical carbon sequestration is zero. Soil carbon pool changes ( This is the focus of this embodiment because high-temperature treatment (typically exceeding 350°C) irreversibly decomposes the organic matter in the soil, causing it to escape as CO2 or volatile organic compounds. Analysis results typically show a significant and widespread decrease in soil organic carbon content. Therefore, the soil acts as a carbon source in this process. It is a positive value.

[0057] S3. Collect carbon source activity data and calculate carbon emissions. The focus is on the accurate measurement of energy consumption, particularly natural gas or electricity consumption data for the thermal desorption unit, as well as the energy and material consumption of auxiliary equipment (such as feed systems and exhaust gas treatment systems). By matching appropriate emission factors, a total carbon emission (C) is calculated. emission ).

[0058] In this embodiment, the material consumption is shown in Table 2, and the energy consumption is shown in Table 3.

[0059] Table 2 Material Consumption List

[0060] Table 3 Energy Consumption Inventory

[0061] In this embodiment, the carbon emissions generated by material and energy consumption are: 4.3982 + 146.6076 = 151.0058t.

[0062] S4. Calculate the change in soil carbon pool. Rigorous sampling and laboratory analysis were conducted on the soil before and after thermal desorption. A positive soil carbon pool disturbance flux was calculated. This indicates that remediation activities not only failed to increase carbon sinks, but also led to the loss of the huge carbon pool of soil, forming an additional and significant carbon source.

[0063] In this embodiment, the impact of in-situ thermal desorption remediation on the soil carbon pool is characterized by a significant loss of organic carbon and a relatively stable inorganic carbon pool. After remediation, the soil organic carbon content decreased from 18.5 g / kg to 12.3 g / kg, a loss of 33.51%, corresponding to a carbon pool loss that translates into approximately 109.78 t CO2 emissions. Inorganic carbon showed no significant fluctuations, and the overall total carbon pool showed a downward trend, with the loss mainly stemming from the decomposition and volatilization of organic carbon caused by high temperatures.

[0064] S5. Calculate net carbon emissions: Applying the core coupling formula of this invention Because of C sink-tech When the value is zero, the formula simplifies to: The net carbon emissions from thermal desorption remediation technology are significantly higher than those calculated using traditional methods that only consider energy and material consumption. The loss of soil organic carbon is a major contributor to the overall carbon footprint, highlighting the necessity and superiority of this approach.

[0065] In this embodiment, the net carbon emissions are: 151.0058t + 109.78t = 260.7858t.

[0066] The system that implements the above embodiments is as follows Figure 3 As shown, it includes a data acquisition module, a factor database module, a multi-source carbon source-carbon sink calculation module, a carbon emission reduction process analysis module, and a results analysis module.

[0067] Activity Data Acquisition Module: As the system's "input end," this module provides a standardized data entry interface for systematically collecting and structuredly storing various activity data throughout the project's entire lifecycle. For example, users can input data such as diesel consumption, cement usage, remediation agent usage, transportation mileage, and soil monitoring data. The module supports data traceability and quality labeling to ensure the reliability of the input data.

[0068] Emission Factor Database Module: As the system's "database," this module contains a dynamically updated database that stores various carbon emission factors (such as power grid factors for different regions and production emission factors for different materials) and carbon sink correlation coefficients (such as the carbon content of different plants) from authoritative domestic and international sources. The database supports intelligent recommendations based on priority, ensuring the standardization of factor selection.

[0069] Carbon Source-Carbon Sink Calculation Module: As the system's "calculation center," this module embeds calculation models and formulas. After completing the sorting and input of activity data and emission factors, the calculation module can automatically perform carbon source emission (C) calculations. emission ), technology carbon sequestration (C sink-tech ), Soil carbon pool change ( ) and final net carbon emissions (C net Complex operations.

[0070] Carbon emission reduction analysis module: Based on the contribution analysis of each carbon source, it identifies key carbon emission links in the remediation project and, in conjunction with a pre-set emission reduction scenario library, evaluates the potential effects of different emission reduction measures.

[0071] The results analysis and report generation module, serving as the system's "output end," transforms calculation results into intuitive visualizations and analytical reports. Users can examine carbon emission composition from different dimensions (such as by project stage, carbon source type, and emission range), clearly identifying key emission links and emission reduction hotspots. The system can automatically generate carbon footprint analysis reports in a standard format, providing strong data support for the comparison of remediation technology solutions, process optimization, and green and low-carbon remediation assessment.

[0072] Therefore, this invention adopts the above-mentioned multi-source data fusion carbon emission calculation method and system for contaminated site remediation. By incorporating the three major carbon flows of "material energy carbon source", "technology carbon sink" and "soil carbon pool disturbance" into a unified calculation framework and integrating multi-source data, it achieves accurate quantification of the net carbon effect of remediation activities. This provides key technical support for the green and low-carbon transformation of the contaminated site remediation industry and helps to promote the transformation of contaminated site remediation from simple pollutant removal to comprehensive environmental governance that takes into account climate benefits.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for calculating carbon emissions from contaminated site remediation using multi-source data fusion, characterized in that, Includes the following steps: S1. Determine the system boundary for carbon emission measurement of contaminated site remediation. The system boundary covers the entire life cycle of the remediation project from material production to final disposal, and incorporates the carbon sink effect of remediation technology and the soil carbon pool effect as measurement elements. S2. Identify all potential carbon sources and potential carbon sinks within the system boundary. Potential carbon sources include energy consumption and material consumption, while potential carbon sinks include the carbon sink effect brought about by remediation technologies and changes in the soil carbon pool. S3. Collect data on potential carbon source activities, and using the emission factor database, calculate multi-source carbon emissions using the emission factor method, denoted as C. emission ; S4. When the remediation technology includes phytoremediation, the amount of carbon fixed by the plant during its growth cycle is calculated using the biomass method based on measured plant biomass data, and is denoted as C. sink-tech ; S5. By conducting stratified sampling and laboratory analysis of the site before and after remediation, measured data including soil organic carbon content, soil bulk density, and gravel content were obtained. The direct monitoring method was used to calculate the change in soil carbon pool storage caused by the remediation activities, denoted as S5. S6. Based on the calculation results of potential carbon sources and potential carbon sinks from multiple dimensions, the net carbon emissions from contaminated site remediation are obtained through coupling analysis, denoted as... .

2. The method for calculating carbon emissions from contaminated site remediation based on multi-source data fusion according to claim 1, characterized in that, In S1, the system boundary includes the material production and transportation stage, the engineering implementation stage, and the post-remediation waste and equipment disposal stage in the time dimension; the spatial boundary is centered on the physical extent of the contaminated site and covers the scope of remediation activities.

3. The method for calculating carbon emissions from contaminated site remediation based on multi-source data fusion according to claim 1, characterized in that, In S2, energy consumption includes the direct and indirect use of various types of energy during the repair process, including the operation of on-site and off-site transportation equipment, repair equipment and auxiliary equipment; material consumption includes the materials and agents put into the repair process, including cement and steel used for on-site facility construction, repair agents and consumables, exhaust gas / wastewater treatment adsorbents and waste disposal-related materials.

4. The method for calculating carbon emissions from contaminated site remediation based on multi-source data fusion according to claim 1, characterized in that, In S2, the carbon sink effect brought about by remediation technology specifically refers to the absorption of atmospheric carbon dioxide by vegetation through photosynthesis and its fixation in biomass in phytoremediation technology; the change in soil carbon pool refers to the change in soil physicochemical properties caused by the implementation of remediation technology, which in turn affects the input, decomposition and transformation process of soil organic carbon, and ultimately causes the net change in soil organic carbon storage.

5. The method for calculating carbon emissions from contaminated site remediation based on multi-source data fusion according to claim 1, characterized in that, In S3, the activity data for energy consumption and material consumption first adopt the original data, including on-site records and procurement records. When the original data is missing, the statistical data of similar projects and industry report data are used as a reference. The emission factors are used in the following order: China Greenhouse Gas Emission Accounting and Reporting Guidelines, emission factors issued by local ecological and environmental departments, international authoritative databases, and publicly published academic reports.

6. The method for calculating carbon emissions from contaminated site remediation based on multi-source data fusion according to claim 5, characterized in that, In S3, carbon source emissions C emission The calculation formula is: ； in, For the activity data of the i-th material, This refers to the carbon emission factor throughout the entire life cycle of the material. For the activity data of the j-th energy source, This represents the carbon emission factor corresponding to this energy source.

7. The method for calculating carbon emissions from contaminated site remediation based on multi-source data fusion according to claim 1, characterized in that, In S4, the biomass method is used to measure carbon sequestration, C sink-tech The calculation formula is: C sink-tech ； Where A is the planting area in m. 2 B represents the plant biomass per unit area (kg / m²). 2 ; The carbon content of herbaceous plants is represented by data from both published data and measured data.

8. The method for calculating carbon emissions from contaminated site remediation based on multi-source data fusion according to claim 1, characterized in that, In S5, the site is divided into several plot units for grid-based sampling based on the degree of site disturbance and soil type. At least three layers of soil samples are collected from the same sampling point before and after remediation. The actual sampling depth is adjusted according to the vertical distribution of pollutants and the depth of remediation disturbance. At least two parallel samples are collected from each layer for homogenization analysis.

9. The method for calculating carbon emissions from contaminated site remediation based on multi-source data fusion according to claim 8, characterized in that, In S5, the change in site carbon pool storage is calculated by measuring the soil organic carbon content before and after remediation. The calculation formula is: ； Where i is the plot sampling unit number, SOC post,i SOC pre,i Soil organic carbon content (g / kg) of sampling unit i in plot i before and after remediation are given, and the average of the two samples is taken; BD i The soil bulk density of sampling unit i is kg / m³ 3 D i Let A be the soil layer depth m for sampling unit i. i Let m be the area of ​​sampling unit i. 2 G i The volume ratio of gravel content in sampling unit i is given, and its diameter is >2mm.

10. A multi-source data fusion system for calculating carbon emissions from contaminated site remediation, characterized in that, It includes a data acquisition module, a factor database module, a multi-source carbon source-carbon sink calculation module, a carbon emission reduction process analysis module, and a results analysis module. The data acquisition module is used to collect activity data on material consumption, energy consumption, plant growth, and soil parameters throughout the entire life cycle of a contaminated site remediation project, through interfaces and manual input. The factor database module is used to hierarchically store emission factors of materials and energy and plant carbon sink parameters corresponding to the activity data. The multi-source carbon source-carbon sink calculation module is connected to the data acquisition module and the factor database module, and is used to calculate carbon source emissions C. emission Technology carbon sequestration C sink-tech and changes in soil carbon storage By performing a coupled analysis of the three factors, the net carbon emissions C were determined. net ; The carbon emission reduction analysis module is used to identify key carbon emission links in the remediation project based on the contribution analysis of each carbon source, and to evaluate the potential effects of different emission reduction measures in conjunction with a pre-set emission reduction scenario library. The results analysis module is used to visualize the net carbon emissions, the distribution of carbon source and sink contributions, key carbon emission links, and the assessment results of emission reduction measures, and automatically generate a carbon footprint analysis report.

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