Carbon emission accounting method applied to cross-regional construction engineering project group

Abstract

The invention relates to the technical field of carbon emission accounting, in particular to a carbon emission accounting method applied to a cross-regional construction engineering project group, and the method comprises the following steps: carrying out the accounting of carbon emission from the macroscopic industry level based on a conventional carbon emission accounting method; and the method is not suitable for carbon emission accounting for cross-regional construction engineering project groups. According to the method, the carbon emission factor method is adopted to check the carbon emission of the cross-regional construction engineering project group, the internal complex relation of the construction engineering project group is considered from the microscopic level to check the carbon emission, and the project group materialization stage is divided into four parts according to the building construction process. According to the method, building material mining production, prefabricated part production, building material transportation and building construction are carried out, a cross-regional construction engineering project group materialization stage carbon emission accounting model is constructed accordingly, and the reasonability and accuracy of cross-regional construction engineering project group carbon emission accounting under the novel urbanization background are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon emission accounting, and particularly to a carbon emission accounting method applied to a cross-regional construction project group. Background Art

[0002] At present, the carbon emission accounting system in the construction engineering field is mainly divided into two dimensions: the macro level of the construction industry and the micro level of construction projects. At the macro level, the input-output analysis method is adopted. By using the industry input-output table to quantify energy consumption and carbon emissions, it has the advantage of a unified accounting system. Scholars have used this method to complete carbon assessments of the provincial and national construction industries, revealing the characteristics and sources of carbon emissions, and providing theoretical support for the low-carbon development of the industry. However, this method has limitations such as high data acquisition thresholds and strong dependence on regional statistical systems, and it is difficult to be promoted in areas with imperfect data.

[0003] At the micro level, it relies on the life cycle assessment method, which is based on the energy demand and material emission data of the entire life cycle of the project (production, construction, operation, demolition) for accounting, and has the characteristics of easy data acquisition and wide applicability. Scholars have completed the quantification and evaluation of the carbon emissions of the entire project cycle through this method, and constructed a micro-project carbon emission accounting framework. However, the existing research has significant deficiencies: first, the macro and micro methods are independent of each other and no cross-scale connection mechanism has been formed; second, the micro accounting focuses on a single project and ignores the complex relationships such as internal resource flow and process intersection in the project group; third, due to geographical dispersion and management fragmentation of cross-regional project groups, there is a lack of systematic tools for carbon emission accounting.

[0004] The existing methods are only applicable to the research on carbon emission accounting in the construction industry and construction projects, and cannot consider the complex relationships within the construction project group from the micro level, resulting in the inability of the existing accounting methods to accurately account for the carbon emissions of the construction project group and making it difficult to provide support for the carbon emission accounting of cross-regional construction project groups. Summary of the Invention

[0005] The purpose of the present invention is to propose a carbon emission accounting method applied to a cross-regional construction project group in order to solve the technical defect problems existing in the prior art described above.

[0006] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A carbon emission accounting method applied to a cross-regional construction project group includes the following steps:

[0008] Step 1: Since most traditional carbon emission accounting methods account for carbon emissions from the macro-industry level and are not applicable to the carbon emission accounting of cross-regional construction project groups, the carbon emission factor method is used to account for the carbon emissions of cross-regional construction project groups, and a carbon emission accounting model is established;

[0009] Step 2: Based on the above carbon emission accounting method and model for cross-regional construction project groups, divide the materialization stage of cross-regional construction project groups into building material extraction and production, precast component production, building material transportation, and building construction, and establish carbon emission accounting models respectively;

[0010] Step 3: Comprehensively account for the carbon emission accounting models of the four stages in Step 2 according to the carbon emission accounting model established in Step 1. By calculating, comparing, and analyzing the data, obtain the carbon emission situation of the cross-regional construction project group.

[0011] As a further description of the above technical solution:

[0012] The carbon emission factor method in Step 1 is a carbon emission estimation method with relatively high recognition. It can construct activity data for emission sources of multiple entities within the system, and use the product of activity data and emission factors as the estimated value of carbon emissions to achieve the carbon emission accounting of the overall system. This method is consistent with the characteristics of multiple entities in the construction project group.

[0013] As a further description of the above technical solution:

[0014] The carbon emission accounting model in Step 1 is specifically as follows:

[0015]

[0016] E i = E ir + E imp + E itp + E is

[0017]

[0018] In the formula, TEC represents the total carbon emissions of the materialization stage of the cross-regional construction project group, E i represents the carbon emissions of the materialization stage of sub-project i within the project group, E ir represents the carbon emissions of building material extraction and production of the i-th project within the project group, E imp represents the carbon emissions of precast component production of the i-th project within the project group, E itp represents the carbon emissions of building material transportation of the i-th project within the project group, E is represents the carbon emissions of building construction of the i-th project within the project group, UCE i represents the carbon emissions of the materialization stage per unit building area of the i-th project within the project group, CFA i represents the building area of the i-th project within the project group.

[0019] As a further description of the above technical solution:

[0020] The carbon emission accounting model for building materials mining and production in step 2 is as follows:

[0021]

[0022] In the formula, E ir M represents the carbon emissions generated by the consumption of various building materials in the construction material mining and production stage of the i-th project in the project group, j represents the amount of the jth building material, f j represents the carbon emission factor of the jth building material considering the recovery factor, θ j Represents the mining and production loss rate of the j-th type of building material.

[0023] As a further description of the above technical solution:

[0024] The carbon emission accounting model for prefabricated component production in step 2 is as follows:

[0025] E imp =∑Cp×AU ei ×f ni′ (i′=1,2)

[0026] In the formula, E imp represents the carbon emissions generated by the consumption of various building materials during the prefabricated component production phase of the i-th project in the project group, C p Represents the concrete volume of precast components, AU e1 Indicates the power consumption per unit volume of concrete produced, AU e2 Indicates the oil consumption per unit volume of concrete produced, f n1 represents the carbon emission factor of electricity, f n2 represents the diesel carbon emission factor.

[0027] As a further description of the above technical solution:

[0028] The carbon emission accounting model for building materials transportation in step 2 is as follows:

[0029]

[0030] In the formula, E itp represents the carbon emissions from building materials transportation of the i-th project in the project group, m ij represents the total consumption of the jth energy source, D ij The average transportation distance of the i-th type of building materials transported by the j-th mode of transportation, K y Indicates the empty vehicle correction factor, because the environmental load when empty is 0.67 times that when fully loaded, so K y =1.67, EF tjIt represents the carbon emission factor per unit mass and per unit transportation distance of the jth type of energy.

[0031] As a further description of the above technical solution:

[0032] The building construction carbon emission accounting model in the second step is specifically as follows:

[0033] E is = T × (AU s1 × f n1 + AU s2 × f n2 )

[0034] In the formula, E is represents the building construction carbon emissions of the ith project in the project group, T represents the construction period, AU s1 represents the daily power consumption, AU s2 represents the daily oil consumption, f n1 represents the carbon emission factor of electricity, f n2 represents the carbon emission factor of diesel.

[0035] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0036] In the present invention, the carbon emission factor method is used to calculate the carbon emissions of a cross-regional construction project group. Considering the complex relationships within the construction project group at the micro level for carbon emission accounting, according to the building construction process, the materialization stage of the project group is divided into four parts, namely building material extraction and production, precast component production, building material transportation, and building construction. Accordingly, a carbon emission accounting model for the materialization stage of a cross-regional construction project group is constructed, improving the rationality and accuracy of carbon emission accounting for cross-regional construction project groups under the background of new urbanization. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the work flow of a carbon emission accounting method for a cross-regional construction project group proposed by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the protection scope of the present invention.

[0039] Please refer to Figure 1 , the present invention provides a technical solution: a carbon emission accounting method for a cross-regional construction project group, including the following steps:

[0040] Step 1. Since most traditional carbon emission accounting methods are used to account for carbon emissions at the macro-industry level and are not applicable to the carbon emission accounting of cross-regional construction project groups, the carbon emission factor method is adopted to account for the carbon emissions of cross-regional construction project groups. The carbon emission factor method is a highly recognized carbon emission estimation method. It can construct activity data for emission sources of multiple entities within the system, and use the product of activity data and emission factors as the estimated value of carbon emissions to achieve the overall carbon emission accounting of the system. This method is consistent with the characteristics of multiple entities in construction project groups, and a carbon emission accounting model is established as follows:

[0041]

[0042] E i = E ir + E imp + E itp + E is

[0043]

[0044] TEC - Total carbon emissions (KgCO2) at the materialization stage of cross-regional construction project groups;

[0045] E i - Carbon emissions (KgCO2) at the materialization stage of Sub-project i within the project group;

[0046] E ir - Carbon emissions (KgCO2) from building material extraction and production of the i-th project within the project group;

[0047] E imp - Carbon emissions (KgCO2) from precast component production of the i-th project within the project group;

[0048] E itp - Carbon emissions (KgCO2) from building material (component) transportation of the i-th project within the project group;

[0049] E is - Carbon emissions (KgCO2) from building construction of the i-th project within the project group;

[0050] UCE i - Carbon emissions (KgCO2) at the materialization stage per unit building area of the i-th project within the project group;

[0051] CFA i - Building area (m2) of the i-th project within the project group.

[0052] Step 2: Based on the above carbon emission accounting method and model for cross-regional construction project clusters, divide the materialization stage of cross-regional building project clusters into building material extraction and production, precast component production, building material transportation, and building construction, and establish carbon emission accounting models respectively;

[0053] (1) Establishment of the carbon emission model for building material extraction and production

[0054] The carbon emissions in the building material extraction and production stage come from the carbon emissions generated during the extraction, processing, and precast component manufacturing of various building materials (including enclosure structure materials, main structure materials, and rough finishing materials). It can be comprehensively calculated by multiplying the building material usage by the carbon emission factor per unit of building material. Existing domestic research generally believes that this stage has the largest carbon emissions except for the operation stage, accounting for about 30% of the entire life cycle. Since the carbon emissions of building materials themselves account for a certain proportion in the whole life cycle of a building, and the selection of building material types will also affect the carbon emissions in the building operation stage, including the carbon emissions of building material extraction and production in the calculation of carbon emissions in the building materialization stage is more in line with the concept of the whole life cycle, tracking and quantitatively analyzing the whole process of the research object, and can also supervise the selection of building materials in the building construction stage to promote the development and application of low-carbon building materials. Therefore, the carbon emission accounting model for building material extraction and production is as follows:

[0055]

[0056] E ir —— The carbon emissions (KgCO2) generated by consuming various building materials in the building material extraction and production stage of the i-th project in the project cluster;

[0057] M j —— The usage amount (t, m 2 、m 3 ) of the j-th building material;

[0058] f j —— The carbon emission factor of the j-th building material considering the recycling coefficient (KgCO2 / t, KgCO2 / m 2 、KgCO2 / m3);

[0059] θ j —— The extraction and production loss rate (%) of the j-th building material.

[0060] (2) Establishment of the carbon emission model for precast component production

[0061] The building components or modules required for a construction project group will be centrally produced in the factory according to certain design specifications. However, due to the different types of precast reinforced concrete components, the volume of the corresponding concrete components and the component production process also change. During the production process of precast components, the factory needs to use a large number of mechanical equipment. To better simulate the carbon emissions of precast component production, the electricity consumption and oil consumption in the factory need to be parameterized with the production of unit volume of concrete components as the unit parameter. In different precast scenarios, through the given volume of precast components, select the energy carbon emission factor corresponding to the production process. Therefore, the carbon emission model for precast component production is as follows:

[0062] E imp = ∑Cp × AU ei × f ni′ (i′ = 1, 2)

[0063] E imp ——The carbon emissions (KgCO2) generated by consuming various building materials during the precast component production stage of the i-th project in the project group;

[0064] C p ——The volume of precast component concrete (m 3 )

[0065] AU e1 ——The electricity consumption per unit volume of concrete production (KWh / m 3 )

[0066] AU e2 ——The oil consumption per unit volume of concrete production (L / m 3 )

[0067] f n1 ——The electricity carbon emission factor (KgCO2 / KWh);

[0068] f n2 ——The diesel carbon emission factor (KgCO2 / L)

[0069] (3) Establishment of the carbon emission model for building materials (components) transportation

[0070] The carbon emissions during transportation are related to factors such as transportation mode, transportation distance, and transportation volume. Considering that the transportation vehicle returns empty from the construction site, an empty vehicle correction coefficient K y is introduced, that is, the actual transportation distance = one-way transportation distance D × K y . The carbon emission model for building materials (components) transportation is as follows:

[0071]

[0072] E itp——Carbon emissions from transportation of building materials (components) of the i-th project in the project group (KgCO2);

[0073] m ij ——Total consumption of the jth energy source (t, KWh, m 3 );

[0074] D ij ——The average transportation distance (km) of the i-th type of building materials (components) transported by the j-th mode of transportation;

[0075] K y ——empty vehicle correction factor. According to existing technical literature, the environmental load when empty is 0.67 times that when fully loaded. Therefore, K y =1.67;

[0076] EF t,j ——Carbon emission factor of the jth energy source per unit mass and unit transportation distance.

[0077] (4) Establishment of a carbon emission model for construction

[0078] Construction is an important link in the production process of building products. It is a production process in which construction companies use certain machines and materials to materially realize the buildings on the design drawings through certain process according to the requirements of the design documents. The energy consumption in the construction process mainly refers to the resources and energy consumption of various mechanical equipment and various construction processes. Its size is mainly determined by the amount and type of building materials, building structure, construction equipment and construction methods. There are four main methods for the inventory calculation in the construction stage: input-output method, on-site energy consumption measurement method, construction procedure energy consumption estimation method, and budget estimation method. This study takes the construction period as the variable observation, and parameterizes the energy consumption such as electricity consumption and oil consumption at the construction site in daily units. Based on this, a carbon emission model for construction is proposed, as follows:

[0079] E is =T×(AU s1 ×f n1 +AU s2 ×f n2 )

[0080] E is ——Construction carbon emissions of the i-th project in the project group (KgCO2);

[0081] T——construction period (days);

[0082] AU s1 ——Daily power consumption (KWh);

[0083] AU s2 ——Daily fuel consumption (L);

[0084] f n1 —— Power carbon emission factor (KgCO2 / KWh);

[0085] f n2 —— Diesel carbon emission factor (KgCO2 / L).

[0086] Step 3: Comprehensively calculate the carbon emission accounting models of the four stages in Step 2 according to the carbon emission accounting model established in Step 1. By calculating, comparing, and analyzing the data, the carbon emission situation of the cross-regional construction project group can be obtained.

[0087] The carbon emission accounting method for this cross-regional construction project group divides the materialization stage of the project group into four parts according to the building construction process, namely building material extraction and production, precast component production, building material (component) transportation, and building construction. Based on this, a carbon emission accounting model for the materialization stage of the cross-regional construction project group is constructed, effectively improving the rationality and accuracy of the carbon emission accounting of the cross-regional construction project group.

[0088] The above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes, should be covered by the protection scope of the present invention.

Claims

1. A carbon emission accounting method applied to a cross-regional construction project group, characterized in that: The following steps are involved: Step 1: Most traditional carbon emission accounting methods calculate carbon emissions from a macro-industry level, which is not suitable for carbon emission accounting for cross-regional construction project groups. Therefore, the carbon emission factor method is used to calculate the carbon emissions of cross-regional construction project groups and establish a carbon emission accounting model; Step 2: Based on the above-mentioned carbon emission accounting method and model of the cross-regional construction project group, the materialization stage of the cross-regional construction project group is divided into building materials mining and production, prefabricated component production, building materials transportation and construction, and carbon emission accounting models are established for each stage; Step 3: Comprehensively calculate the four-stage carbon emission accounting model in step 2 according to the carbon emission accounting model established in step 1. By calculating, comparing and analyzing the data, the carbon emission situation of the cross-regional construction project group is obtained.

2. A carbon emission accounting method for a cross-regional construction project group according to claim 1, characterized in that: The carbon emission factor method in step one is a highly recognized carbon emission estimation method. It can construct activity data for emission sources of multiple entities in the system, and use the product of activity data and emission factors as the carbon emission estimate to achieve carbon emission accounting for the system as a whole. This method is consistent with the characteristics of multiple entities in a construction project group.

3. According to claim 1, a carbon emission accounting method applied to a cross-regional construction project group is characterized in that: The carbon emission accounting model in step 1 is as follows: AND i =And ir +E imp +E itp +E is In the formula, TEC represents the total carbon emissions of the materialization stage of the cross-regional construction project group, E i represents the carbon emissions of sub-project i in the project group during the materialization phase, E ir represents the carbon emissions from the mining and production of building materials for the i-th project in the project group, E imp represents the carbon emissions of prefabricated component production of the i-th project in the project group, E itp represents the carbon emissions from building materials transportation of the i-th project in the project group, E is represents the carbon emissions of construction of the i-th project in the project group, UCE i represents the carbon emissions per unit building area of ​​the i-th project in the project group, CFA i Represents the building area of ​​the i-th project in the project group.

4. The carbon emission accounting method for a cross-regional construction project group according to claim 1 is characterized in that: The carbon emission accounting model for building materials mining and production in step 2 is as follows: In the formula, E ir M represents the carbon emissions generated by the consumption of various building materials in the construction material mining and production stage of the i-th project in the project group, j represents the amount of the jth building material, f j represents the carbon emission factor of the jth building material considering the recovery factor, θ j Represents the mining and production loss rate of the j-th type of building material.

5. The carbon emission accounting method for a cross-regional construction project group according to claim 1 is characterized in that: The carbon emission accounting model for prefabricated component production in step 2 is as follows: E imp =∑Cp×AU ei ×f ni′ (i′=1,2) In the formula, E imp represents the carbon emissions generated by the consumption of various building materials during the prefabricated component production phase of the i-th project in the project group, C p Represents the concrete volume of precast components, AU e1 Indicates the power consumption per unit volume of concrete produced, AU e2 Indicates the oil consumption per unit volume of concrete produced, f n1 represents the carbon emission factor of electricity, f n2 represents the diesel carbon emission factor.

6. The carbon emission accounting method for a cross-regional construction project group according to claim 1 is characterized in that: The carbon emission accounting model for building materials transportation in step 2 is as follows: In the formula, E itp represents the carbon emissions from building materials transportation of the i-th project in the project group, m ij represents the total consumption of the jth energy source, D ij The average transportation distance of the i-th type of building materials transported by the j-th mode of transportation, K y Indicates the empty vehicle correction factor, because the environmental load when empty is 0.67 times that when fully loaded, so K y =1.67, EF tj It represents the carbon emission factor of the j-th energy per unit mass and per unit transportation distance.

7. The carbon emission accounting method for a cross-regional construction project group according to claim 1 is characterized in that: The construction carbon emission accounting model in step 2 is as follows: HAVE BEEN is =T×(AU s1 ×f n1 +AU s2 ×f n2 ) In the formula, E is represents the carbon emission of construction of the i-th project in the project group, T represents the construction period, AU s1 Daily power consumption, AU s2 Indicates daily fuel consumption, f n1 represents the carbon emission factor of electricity, f n2 represents the diesel carbon emission factor.

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